//
// MIT license
// Copyright (C) 2024 Intel Corporation
// SPDX-License-Identifier: MIT
//

//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//

#ifndef GGML_SYCL_DPCT_HELPER_HPP
#define GGML_SYCL_DPCT_HELPER_HPP

#include <sycl/sycl.hpp>
#include <sycl/half_type.hpp>
#include <oneapi/mkl.hpp>
#include <map>

#include "ggml.h"

#if defined(__linux__)
#include <sys/mman.h>
#elif defined(_WIN64)
#ifndef NOMINMAX
#define NOMINMAX
#endif
#include <windows.h>
#else
#error "Only support Windows and Linux."
#endif

#if defined(__linux__)
#include <unistd.h>
#include <sys/syscall.h>
#endif
#if defined(_WIN64)
#ifndef NOMINMAX
#define NOMINMAX
#endif
#include <windows.h>
#endif

#define DPCT_COMPATIBILITY_TEMP (900)

#if defined(_MSC_VER)
#define __dpct_align__(n) __declspec(align(n))
#define __dpct_inline__ __forceinline
#else
#define __dpct_align__(n) __attribute__((aligned(n)))
#define __dpct_inline__ __inline__ __attribute__((always_inline))
#endif

#if defined(_MSC_VER)
#define __dpct_noinline__ __declspec(noinline)
#else
#define __dpct_noinline__ __attribute__((noinline))
#endif

inline std::string get_device_type_name(const sycl::device &Device) {
    auto DeviceType = Device.get_info<sycl::info::device::device_type>();
    switch (DeviceType) {
    case sycl::info::device_type::cpu:
        return "cpu";
    case sycl::info::device_type::gpu:
        return "gpu";
    case sycl::info::device_type::host:
        return "host";
    case sycl::info::device_type::accelerator:
        return "acc";
    default:
        return "unknown";
    }
}

inline std::string get_device_backend_and_type(const sycl::device &device) {
    std::stringstream device_type;
    sycl::backend backend = device.get_backend();
    device_type <<  backend << ":" << get_device_type_name(device);
    return device_type.str();
}

namespace dpct
{
    typedef sycl::queue *queue_ptr;
    typedef sycl::event *event_ptr;
    typedef char *device_ptr;
    typedef uint8_t byte_t;
    typedef sycl::buffer<byte_t> buffer_t;

    /// SYCL default exception handler
    inline auto exception_handler = [](sycl::exception_list exceptions)
    {
        for (std::exception_ptr const &e : exceptions)
        {
            try
            {
                std::rethrow_exception(e);
            }
            catch (sycl::exception const &e)
            {
                std::cerr << "Caught asynchronous SYCL exception:" << std::endl
                          << e.what() << std::endl
                          << "Exception caught at file:" << __FILE__
                          << ", line:" << __LINE__ << std::endl;
            }
        }
    };

    enum error_code
    {
        success = 0,
        default_error = 999
    };

    enum memcpy_direction
    {
        host_to_host,
        host_to_device,
        device_to_host,
        device_to_device,
        automatic
    };

    enum memory_region
    {
        global = 0, // device global memory
        constant,   // device constant memory
        local,      // device local memory
        shared,     // memory which can be accessed by host and device
    };

    enum class library_data_t : unsigned char
    {
        real_float = 0,
        complex_float,
        real_double,
        complex_double,
        real_half,
        complex_half,
        real_bfloat16,
        complex_bfloat16,
        real_int4,
        complex_int4,
        real_uint4,
        complex_uint4,
        real_int8,
        complex_int8,
        real_uint8,
        complex_uint8,
        real_int16,
        complex_int16,
        real_uint16,
        complex_uint16,
        real_int32,
        complex_int32,
        real_uint32,
        complex_uint32,
        real_int64,
        complex_int64,
        real_uint64,
        complex_uint64,
        real_int8_4,
        real_int8_32,
        real_uint8_4,
        library_data_t_size
    };

    template <typename T>
    struct DataType
    {
        using T2 = T;
    };
    template <typename T>
    struct DataType<sycl::vec<T, 2>>
    {
        using T2 = std::complex<T>;
    };

    static void destroy_event(event_ptr event)
    {
        delete event;
    }

    static inline unsigned int get_tid()
    {
#if defined(__linux__)
        return syscall(SYS_gettid);
#elif defined(_WIN64)
        return GetCurrentThreadId();
#else
#error "Only support Windows and Linux."
#endif
    }

    namespace detail
    {
        static void get_version(const sycl::device &dev, int &major, int &minor)
        {
            // Version string has the following format:
            // a. OpenCL<space><major.minor><space><vendor-specific-information>
            // b. <major.minor>
            // c. <AmdGcnArchName> e.g gfx1030
            std::string ver;
            ver = dev.get_info<sycl::info::device::version>();
            std::string::size_type i = 0;
            while (i < ver.size()) {
              if (isdigit(ver[i]))
                break;
              i++;
            }
            major = std::stoi(&(ver[i]));
            while (i < ver.size()) {
              if (ver[i] == '.')
                break;
              i++;
            }
            if (i < ver.size()) {
              // a. and b.
              i++;
              minor = std::stoi(&(ver[i]));
            } else {
              // c.
              minor = 0;
            }
        }

        template <typename tag, typename T>
        class generic_error_type
        {
        public:
            generic_error_type() = default;
            generic_error_type(T value) : value{value} {}
            operator T() const { return value; }

        private:
            T value;
        };

    } // namespace detail

    /// Pitched 2D/3D memory data.
    class pitched_data
    {
    public:
        pitched_data() : pitched_data(nullptr, 0, 0, 0) {}
        pitched_data(void *data, size_t pitch, size_t x, size_t y)
            : _data(data), _pitch(pitch), _x(x), _y(y) {}

        void *get_data_ptr() { return _data; }
        void set_data_ptr(void *data) { _data = data; }

        size_t get_pitch() { return _pitch; }
        void set_pitch(size_t pitch) { _pitch = pitch; }

        size_t get_x() { return _x; }
        void set_x(size_t x) { _x = x; }

        size_t get_y() { return _y; }
        void set_y(size_t y) { _y = y; }

    private:
        void *_data;
        size_t _pitch, _x, _y;
    };

    class device_info
    {
    public:
        // get interface
        const char *get_name() const { return _name; }
        char *get_name() { return _name; }
        template <typename WorkItemSizesTy = sycl::range<3>,
                  std::enable_if_t<std::is_same_v<WorkItemSizesTy, sycl::range<3>> ||
                                       std::is_same_v<WorkItemSizesTy, int *>,
                                   int> = 0>
        auto get_max_work_item_sizes() const
        {
            if constexpr (std::is_same_v<WorkItemSizesTy, sycl::range<3>>)
                return sycl::range<3>(_max_work_item_sizes_i[0],
                                      _max_work_item_sizes_i[1],
                                      _max_work_item_sizes_i[2]);
            else
            {
                return _max_work_item_sizes_i;
            }
        }
        template <typename WorkItemSizesTy = sycl::range<3>,
                  std::enable_if_t<std::is_same_v<WorkItemSizesTy, sycl::range<3>> ||
                                       std::is_same_v<WorkItemSizesTy, int *>,
                                   int> = 0>
        auto get_max_work_item_sizes()
        {
            if constexpr (std::is_same_v<WorkItemSizesTy, sycl::range<3>>)
                return sycl::range<3>(_max_work_item_sizes_i[0],
                                      _max_work_item_sizes_i[1],
                                      _max_work_item_sizes_i[2]);
            else
            {
                return _max_work_item_sizes_i;
            }
        }
        bool get_host_unified_memory() const { return _host_unified_memory; }
        int get_major_version() const { return _major; }
        int get_minor_version() const { return _minor; }
        int get_integrated() const { return _integrated; }
        int get_max_clock_frequency() const { return _frequency; }
        int get_max_compute_units() const { return _max_compute_units; }
        int get_max_work_group_size() const { return _max_work_group_size; }
        int get_max_sub_group_size() const { return _max_sub_group_size; }
        int get_max_work_items_per_compute_unit() const
        {
            return _max_work_items_per_compute_unit;
        }
        int get_max_register_size_per_work_group() const
        {
            return _max_register_size_per_work_group;
        }
        template <typename NDRangeSizeTy = size_t *,
                  std::enable_if_t<std::is_same_v<NDRangeSizeTy, size_t *> ||
                                       std::is_same_v<NDRangeSizeTy, int *>,
                                   int> = 0>
        auto get_max_nd_range_size() const
        {
            if constexpr (std::is_same_v<NDRangeSizeTy, size_t *>)
                return _max_nd_range_size;
            else
                return _max_nd_range_size_i;
        }
        template <typename NDRangeSizeTy = size_t *,
                  std::enable_if_t<std::is_same_v<NDRangeSizeTy, size_t *> ||
                                       std::is_same_v<NDRangeSizeTy, int *>,
                                   int> = 0>
        auto get_max_nd_range_size()
        {
            if constexpr (std::is_same_v<NDRangeSizeTy, size_t *>)
                return _max_nd_range_size;
            else
                return _max_nd_range_size_i;
        }
        size_t get_global_mem_size() const { return _global_mem_size; }
        size_t get_local_mem_size() const { return _local_mem_size; }
        size_t get_max_mem_alloc_size() const { return _max_mem_alloc_size; }
        /// Returns the maximum clock rate of device's global memory in kHz. If
        /// compiler does not support this API then returns default value 3200000 kHz.
        unsigned int get_memory_clock_rate() const { return _memory_clock_rate; }
        /// Returns the maximum bus width between device and memory in bits. If
        /// compiler does not support this API then returns default value 64 bits.
        unsigned int get_memory_bus_width() const { return _memory_bus_width; }
        uint32_t get_device_id() const { return _device_id; }
        std::array<unsigned char, 16> get_uuid() const { return _uuid; }
        /// Returns global memory cache size in bytes.
        unsigned int get_global_mem_cache_size() const
        {
            return _global_mem_cache_size;
        }

        // set interface
        void set_name(const char *name)
        {
            size_t length = strlen(name);
            if (length < 256)
            {
                std::memcpy(_name, name, length + 1);
            }
            else
            {
                std::memcpy(_name, name, 255);
                _name[255] = '\0';
            }
        }
        void set_max_work_item_sizes(const sycl::range<3> max_work_item_sizes)
        {
            for (int i = 0; i < 3; ++i)
                _max_work_item_sizes_i[i] = max_work_item_sizes[i];
        }
        [[deprecated]] void
        set_max_work_item_sizes(const sycl::id<3> max_work_item_sizes)
        {
            for (int i = 0; i < 3; ++i)
            {
                _max_work_item_sizes_i[i] = max_work_item_sizes[i];
            }
        }
        void set_host_unified_memory(bool host_unified_memory)
        {
            _host_unified_memory = host_unified_memory;
        }
        void set_major_version(int major) { _major = major; }
        void set_minor_version(int minor) { _minor = minor; }
        void set_integrated(int integrated) { _integrated = integrated; }
        void set_max_clock_frequency(int frequency) { _frequency = frequency; }
        void set_max_compute_units(int max_compute_units)
        {
            _max_compute_units = max_compute_units;
        }
        void set_global_mem_size(size_t global_mem_size)
        {
            _global_mem_size = global_mem_size;
        }
        void set_local_mem_size(size_t local_mem_size)
        {
            _local_mem_size = local_mem_size;
        }
        void set_max_mem_alloc_size(size_t max_mem_alloc_size)
        {
            _max_mem_alloc_size = max_mem_alloc_size;
        }
        void set_max_work_group_size(int max_work_group_size)
        {
            _max_work_group_size = max_work_group_size;
        }
        void set_max_sub_group_size(int max_sub_group_size)
        {
            _max_sub_group_size = max_sub_group_size;
        }
        void
        set_max_work_items_per_compute_unit(int max_work_items_per_compute_unit)
        {
            _max_work_items_per_compute_unit = max_work_items_per_compute_unit;
        }
        void set_max_nd_range_size(int max_nd_range_size[])
        {
            for (int i = 0; i < 3; i++)
            {
                _max_nd_range_size[i] = max_nd_range_size[i];
                _max_nd_range_size_i[i] = max_nd_range_size[i];
            }
        }
        void set_memory_clock_rate(unsigned int memory_clock_rate)
        {
            _memory_clock_rate = memory_clock_rate;
        }
        void set_memory_bus_width(unsigned int memory_bus_width)
        {
            _memory_bus_width = memory_bus_width;
        }
        void
        set_max_register_size_per_work_group(int max_register_size_per_work_group)
        {
            _max_register_size_per_work_group = max_register_size_per_work_group;
        }
        void set_device_id(uint32_t device_id)
        {
            _device_id = device_id;
        }
        void set_uuid(std::array<unsigned char, 16> uuid)
        {
            _uuid = std::move(uuid);
        }
        void set_global_mem_cache_size(unsigned int global_mem_cache_size)
        {
            _global_mem_cache_size = global_mem_cache_size;
        }

    private:
        char _name[256];
        int _max_work_item_sizes_i[3];
        bool _host_unified_memory = false;
        int _major;
        int _minor;
        int _integrated = 0;
        int _frequency;
        // Set estimated value 3200000 kHz as default value.
        unsigned int _memory_clock_rate = 3200000;
        // Set estimated value 64 bits as default value.
        unsigned int _memory_bus_width = 64;
        unsigned int _global_mem_cache_size;
        int _max_compute_units;
        int _max_work_group_size;
        int _max_sub_group_size;
        int _max_work_items_per_compute_unit;
        int _max_register_size_per_work_group;
        size_t _global_mem_size;
        size_t _local_mem_size;
        size_t _max_mem_alloc_size;
        size_t _max_nd_range_size[3];
        int _max_nd_range_size_i[3];
        uint32_t _device_id;
        std::array<unsigned char, 16> _uuid;
    };

    static int get_major_version(const sycl::device &dev)
    {
        int major, minor;
        detail::get_version(dev, major, minor);
        return major;
    }

    static int get_minor_version(const sycl::device &dev)
    {
        int major, minor;
        detail::get_version(dev, major, minor);
        return minor;
    }

    static void get_device_info(device_info &out, const sycl::device &dev)
    {
        device_info prop;
        prop.set_name(dev.get_info<sycl::info::device::name>().c_str());

        int major, minor;
        detail::get_version(dev, major, minor);
        prop.set_major_version(major);
        prop.set_minor_version(minor);

        prop.set_max_work_item_sizes(
#if (__SYCL_COMPILER_VERSION && __SYCL_COMPILER_VERSION < 20220902)
            // oneAPI DPC++ compiler older than 2022/09/02, where max_work_item_sizes
            // is an enum class element
            dev.get_info<sycl::info::device::max_work_item_sizes>());
#else
            // SYCL 2020-conformant code, max_work_item_sizes is a struct templated by
            // an int
            dev.get_info<sycl::info::device::max_work_item_sizes<3>>());
#endif
        prop.set_host_unified_memory(dev.has(sycl::aspect::usm_host_allocations));

        prop.set_max_clock_frequency(
            dev.get_info<sycl::info::device::max_clock_frequency>() * 1000);

        prop.set_max_compute_units(
            dev.get_info<sycl::info::device::max_compute_units>());
        prop.set_max_work_group_size(
            dev.get_info<sycl::info::device::max_work_group_size>());
        prop.set_global_mem_size(dev.get_info<sycl::info::device::global_mem_size>());
        prop.set_local_mem_size(dev.get_info<sycl::info::device::local_mem_size>());
        prop.set_max_mem_alloc_size(dev.get_info<sycl::info::device::max_mem_alloc_size>());

#if (defined(SYCL_EXT_INTEL_DEVICE_INFO) && SYCL_EXT_INTEL_DEVICE_INFO >= 6)
        if (dev.has(sycl::aspect::ext_intel_memory_clock_rate))
        {
            unsigned int tmp =
                dev.get_info<sycl::ext::intel::info::device::memory_clock_rate>();
            if (tmp != 0)
                prop.set_memory_clock_rate(1000 * tmp);
        }
        if (dev.has(sycl::aspect::ext_intel_memory_bus_width))
        {
            prop.set_memory_bus_width(
                dev.get_info<sycl::ext::intel::info::device::memory_bus_width>());
        }
        if (dev.has(sycl::aspect::ext_intel_device_id))
        {
            prop.set_device_id(
                dev.get_info<sycl::ext::intel::info::device::device_id>());
        }
        if (dev.has(sycl::aspect::ext_intel_device_info_uuid))
        {
            prop.set_uuid(dev.get_info<sycl::ext::intel::info::device::uuid>());
        }
#elif defined(_MSC_VER) && !defined(__clang__)
#pragma message("get_device_info: querying memory_clock_rate and \
        memory_bus_width are not supported by the compiler used. \
        Use 3200000 kHz as memory_clock_rate default value. \
        Use 64 bits as memory_bus_width default value.")
#else
#warning "get_device_info: querying memory_clock_rate and \
        memory_bus_width are not supported by the compiler used. \
        Use 3200000 kHz as memory_clock_rate default value. \
        Use 64 bits as memory_bus_width default value."
#endif

        size_t max_sub_group_size = 1;
        std::vector<size_t> sub_group_sizes =
            dev.get_info<sycl::info::device::sub_group_sizes>();

        for (const auto &sub_group_size : sub_group_sizes)
        {
            if (max_sub_group_size < sub_group_size)
                max_sub_group_size = sub_group_size;
        }

        prop.set_max_sub_group_size(max_sub_group_size);

        prop.set_max_work_items_per_compute_unit(
            dev.get_info<sycl::info::device::max_work_group_size>());
        int max_nd_range_size[] = {0x7FFFFFFF, 0x7FFFFFFF, 0x7FFFFFFF};
        prop.set_max_nd_range_size(max_nd_range_size);

        // Estimates max register size per work group, feel free to update the value
        // according to device properties.
        prop.set_max_register_size_per_work_group(65536);

        prop.set_global_mem_cache_size(
            dev.get_info<sycl::info::device::global_mem_cache_size>());
        out = prop;
    }

   /// dpct device extension
    class device_ext : public sycl::device {
      typedef std::mutex mutex_type;

     public:
      device_ext() : sycl::device() {}
      ~device_ext() {
        std::lock_guard<mutex_type> lock(m_mutex);
        clear_queues();
      }
      device_ext(const sycl::device &base) : sycl::device(base) {
        std::lock_guard<mutex_type> lock(m_mutex);
        init_queues();
      }

      int is_native_atomic_supported() { return 0; }
      int get_major_version() const { return dpct::get_major_version(*this); }

      int get_minor_version() const { return dpct::get_minor_version(*this); }

      int get_max_compute_units() const {
        return get_device_info().get_max_compute_units();
      }

      /// Return the maximum clock frequency of this device in KHz.
      int get_max_clock_frequency() const {
        return get_device_info().get_max_clock_frequency();
      }

      int get_integrated() const { return get_device_info().get_integrated(); }

      int get_max_sub_group_size() const {
        return get_device_info().get_max_sub_group_size();
      }

      int get_max_register_size_per_work_group() const {
        return get_device_info().get_max_register_size_per_work_group();
      }

      int get_max_work_group_size() const {
        return get_device_info().get_max_work_group_size();
      }

      int get_mem_base_addr_align() const {
        return get_info<sycl::info::device::mem_base_addr_align>();
      }

      size_t get_global_mem_size() const {
        return get_device_info().get_global_mem_size();
      }

      size_t get_max_mem_alloc_size() const {
        return get_device_info().get_max_mem_alloc_size();
      }

      /// Get the number of bytes of free and total memory on the SYCL device.
      /// \param [out] free_memory The number of bytes of free memory on the
      /// SYCL device. \param [out] total_memory The number of bytes of total
      /// memory on the SYCL device.
      void get_memory_info(size_t &free_memory, size_t &total_memory) {
        total_memory = get_device_info().get_global_mem_size();
        const char *warning_info =
            "get_memory_info: [warning] ext_intel_free_memory is not "
            "supported (export/set ZES_ENABLE_SYSMAN=1 to support), "
            "use total memory as free memory";
#if (defined(__SYCL_COMPILER_VERSION) && __SYCL_COMPILER_VERSION >= 20221105)
        if (!has(sycl::aspect::ext_intel_free_memory)) {
          std::cerr << warning_info << std::endl;
          free_memory = total_memory;
        } else {
          free_memory = get_info<sycl::ext::intel::info::device::free_memory>();
        }
#else
        std::cerr << warning_info << std::endl;
        free_memory = total_memory;
#if defined(_MSC_VER) && !defined(__clang__)
#pragma message("Querying the number of bytes of free memory is not supported")
#else
#warning "Querying the number of bytes of free memory is not supported"
#endif
#endif
      }

      void get_device_info(device_info &out) const {
        dpct::get_device_info(out, *this);
      }

      device_info get_device_info() const {
        device_info prop;
        dpct::get_device_info(prop, *this);
        return prop;
      }

      void reset() {
        std::lock_guard<mutex_type> lock(m_mutex);
        clear_queues();
        init_queues();
      }

      sycl::queue &in_order_queue() { return _q_in_order; }

      sycl::queue &out_of_order_queue() { return _q_out_of_order; }

      sycl::queue &default_queue() { return in_order_queue(); }

      void queues_wait_and_throw() {
        std::unique_lock<mutex_type> lock(m_mutex);
        lock.unlock();
        for (auto &q : _queues) {
          q.wait_and_throw();
        }
        // Guard the destruct of current_queues to make sure the ref count is
        // safe.
        lock.lock();
      }

      sycl::queue create_queue(bool enable_exception_handler = false) {
        return create_in_order_queue(enable_exception_handler);
      }

      sycl::queue create_queue(sycl::device device,
                               bool enable_exception_handler = false) {
        return create_in_order_queue(device, enable_exception_handler);
      }

      sycl::queue create_in_order_queue(bool enable_exception_handler = false) {
        std::lock_guard<mutex_type> lock(m_mutex);
        return create_queue_impl(enable_exception_handler,
                                 sycl::property::queue::in_order());
      }

      sycl::queue create_in_order_queue(sycl::device device,
                                        bool enable_exception_handler = false) {
        std::lock_guard<mutex_type> lock(m_mutex);
        return create_queue_impl(device, enable_exception_handler,
                                 sycl::property::queue::in_order());
      }

      sycl::queue create_out_of_order_queue(
          bool enable_exception_handler = false) {
        std::lock_guard<mutex_type> lock(m_mutex);
        return create_queue_impl(enable_exception_handler);
      }

      void destroy_queue(sycl::queue queue) {
        std::lock_guard<mutex_type> lock(m_mutex);
        _queues.clear();
      }
      void set_saved_queue(sycl::queue q) {
        std::lock_guard<mutex_type> lock(m_mutex);
        _saved_queue = q;
      }
      sycl::queue get_saved_queue() const {
        std::lock_guard<mutex_type> lock(m_mutex);
        return _saved_queue;
      }

     private:
      void clear_queues() { _queues.clear(); }

      void init_queues() {
        _q_in_order =
            create_queue_impl(true, sycl::property::queue::in_order());
        _q_out_of_order = create_queue_impl(true);
        _saved_queue = default_queue();
      }

      /// Caller should acquire resource \p m_mutex before calling this
      /// function.
      template <class... Properties>
      sycl::queue create_queue_impl(bool enable_exception_handler,
                                    Properties... properties) {
        sycl::async_handler eh = {};
        if (enable_exception_handler) {
          eh = exception_handler;
        }
        auto q = sycl::queue(*this, eh,
                             sycl::property_list(
#ifdef DPCT_PROFILING_ENABLED
                                 sycl::property::queue::enable_profiling(),
#endif
                                 properties...));
        _queues.push_back(q);

        return _queues.back();
      }

      template <class... Properties>
      sycl::queue create_queue_impl(sycl::device device,
                                    bool enable_exception_handler,
                                    Properties... properties) {
        sycl::async_handler eh = {};
        if (enable_exception_handler) {
          eh = exception_handler;
        }
        _queues.push_back(
            sycl::queue(device, eh,
                        sycl::property_list(
#ifdef DPCT_PROFILING_ENABLED
                            sycl::property::queue::enable_profiling(),
#endif
                            properties...)));

        return _queues.back();
      }

      void get_version(int &major, int &minor) const {
        detail::get_version(*this, major, minor);
      }
      sycl::queue _q_in_order, _q_out_of_order;
      sycl::queue _saved_queue;
      std::vector<sycl::queue> _queues;
      mutable mutex_type m_mutex;
    };


    /// device manager
    class dev_mgr
    {
    public:
        device_ext &current_device()
        {
            unsigned int dev_id = current_device_id();
            check_id(dev_id);
            return *_devs[dev_id];
        }
        device_ext &cpu_device() const
        {
            std::lock_guard<std::recursive_mutex> lock(m_mutex);
            if (_cpu_device == -1)
            {
                throw std::runtime_error("no valid cpu device");
            }
            else
            {
                return *_devs[_cpu_device];
            }
        }
        device_ext &get_device(unsigned int id) const
        {
            std::lock_guard<std::recursive_mutex> lock(m_mutex);
            check_id(id);
            return *_devs[id];
        }
        unsigned int current_device_id() const
        {
            std::lock_guard<std::recursive_mutex> lock(m_mutex);
            auto it = _thread2dev_map.find(get_tid());
            if (it != _thread2dev_map.end())
                return it->second;
            return DEFAULT_DEVICE_ID;
        }

        /// Select device with a device ID.
        /// \param [in] id The id of the device which can
        /// be obtained through get_device_id(const sycl::device).
        void select_device(unsigned int id)
        {
            std::lock_guard<std::recursive_mutex> lock(m_mutex);
            check_id(id);
            _thread2dev_map[get_tid()] = id;
        }
        unsigned int device_count() { return _devs.size(); }

        unsigned int get_device_id(const sycl::device &dev)
        {
            unsigned int id = 0;
            for (auto dev_item : _devs)
            {
                if (*dev_item == dev)
                {
                    break;
                }
                id++;
            }
            return id;
        }

        template <class DeviceSelector>
        std::enable_if_t<
            std::is_invocable_r_v<int, DeviceSelector, const sycl::device &>>
        select_device(const DeviceSelector &selector = sycl::gpu_selector_v)
        {
            sycl::device selected_device = sycl::device(selector);
            unsigned int selected_device_id = get_device_id(selected_device);
            select_device(selected_device_id);
        }

        /// Returns the instance of device manager singleton.
        static dev_mgr &instance()
        {
            static dev_mgr d_m;
            return d_m;
        }
        dev_mgr(const dev_mgr &) = delete;
        dev_mgr &operator=(const dev_mgr &) = delete;
        dev_mgr(dev_mgr &&) = delete;
        dev_mgr &operator=(dev_mgr &&) = delete;

    private:
        mutable std::recursive_mutex m_mutex;
        static bool compare_dev(sycl::device &device1, sycl::device &device2)
        {
            sycl::backend backend1 = device1.get_backend();
            sycl::backend backend2 = device2.get_backend();
            // levelzero backends always come first
            if(backend1 == sycl::backend::ext_oneapi_level_zero && backend2 != sycl::backend::ext_oneapi_level_zero) return true;
            if(backend1 != sycl::backend::ext_oneapi_level_zero && backend2 == sycl::backend::ext_oneapi_level_zero) return false;
            dpct::device_info prop1;
            dpct::get_device_info(prop1, device1);
            dpct::device_info prop2;
            dpct::get_device_info(prop2, device2);
            return prop1.get_max_compute_units() > prop2.get_max_compute_units();
        }
        static int convert_backend_index(std::string & backend) {
            if (backend == "ext_oneapi_level_zero:gpu") return 0;
            if (backend == "opencl:gpu") return 1;
            if (backend == "ext_oneapi_cuda:gpu") return 2;
            if (backend == "ext_oneapi_hip:gpu") return 3;
            if (backend == "opencl:cpu") return 4;
            if (backend == "opencl:acc") return 5;
            printf("convert_backend_index: can't handle backend=%s\n", backend.c_str());
            GGML_ASSERT(false);
        }
        static bool compare_backend(std::string &backend1, std::string &backend2) {
            return convert_backend_index(backend1) < convert_backend_index(backend2);
        }
        dev_mgr()
        {
            sycl::device default_device =
                sycl::device(sycl::default_selector_v);
            _devs.push_back(std::make_shared<device_ext>(default_device));

            std::vector<sycl::device> sycl_all_devs;
            // Collect other devices except for the default device.
            if (default_device.is_cpu())
                _cpu_device = 0;

            auto Platforms = sycl::platform::get_platforms();
            // Keep track of the number of devices per backend
            std::map<sycl::backend, size_t> DeviceNums;
            std::map<std::string, std::vector<sycl::device>> backend_devices;

            while (!Platforms.empty()) {
                auto Platform = Platforms.back();
                Platforms.pop_back();
                auto devices = Platform.get_devices();
                std::string backend_type = get_device_backend_and_type(devices[0]);
                for (const auto &device : devices) {
                    backend_devices[backend_type].push_back(device);
                }
            }

            std::vector<std::string> keys;
            for(auto it = backend_devices.begin(); it != backend_devices.end(); ++it) {
                keys.push_back(it->first);
            }
            std::sort(keys.begin(), keys.end(), compare_backend);

            for (auto &key : keys) {
                std::vector<sycl::device> devs = backend_devices[key];
                std::sort(devs.begin(), devs.end(), compare_dev);
                for (const auto &dev : devs) {
                    sycl_all_devs.push_back(dev);
                }
            }

            for (auto &dev : sycl_all_devs)
            {
                if (dev == default_device)
                {
                    continue;
                }
                _devs.push_back(std::make_shared<device_ext>(dev));
                if (_cpu_device == -1 && dev.is_cpu())
                {
                    _cpu_device = _devs.size() - 1;
                }
            }
        }
        void check_id(unsigned int id) const
        {
            if (id >= _devs.size())
            {
                throw std::runtime_error("invalid device id");
            }
        }
        std::vector<std::shared_ptr<device_ext>> _devs;
        /// DEFAULT_DEVICE_ID is used, if current_device_id() can not find current
        /// thread id in _thread2dev_map, which means default device should be used
        /// for the current thread.
        const unsigned int DEFAULT_DEVICE_ID = 0;
        /// thread-id to device-id map.
        std::map<unsigned int, unsigned int> _thread2dev_map;
        int _cpu_device = -1;
    };

    static inline sycl::queue &get_default_queue()
    {
        return dev_mgr::instance().current_device().default_queue();
    }

    namespace detail
    {
        enum class pointer_access_attribute
        {
            host_only = 0,
            device_only,
            host_device,
            end
        };

        static pointer_access_attribute get_pointer_attribute(sycl::queue &q,
                                                              const void *ptr)
        {
            switch (sycl::get_pointer_type(ptr, q.get_context()))
            {
            case sycl::usm::alloc::unknown:
                return pointer_access_attribute::host_only;
            case sycl::usm::alloc::device:
                return pointer_access_attribute::device_only;
            case sycl::usm::alloc::shared:
            case sycl::usm::alloc::host:
                return pointer_access_attribute::host_device;
            }
        }

        template <typename ArgT>
        inline constexpr std::uint64_t get_type_combination_id(ArgT Val)
        {
            static_assert((unsigned char)library_data_t::library_data_t_size <=
                              std::numeric_limits<unsigned char>::max() &&
                          "library_data_t size exceeds limit.");
            static_assert(std::is_same_v<ArgT, library_data_t>, "Unsupported ArgT");
            return (std::uint64_t)Val;
        }

        template <typename FirstT, typename... RestT>
        inline constexpr std::uint64_t get_type_combination_id(FirstT FirstVal,
                                                               RestT... RestVal)
        {
            static_assert((std::uint8_t)library_data_t::library_data_t_size <=
                              std::numeric_limits<unsigned char>::max() &&
                          "library_data_t size exceeds limit.");
            static_assert(sizeof...(RestT) <= 8 && "Too many parameters");
            static_assert(std::is_same_v<FirstT, library_data_t>, "Unsupported FirstT");
            return get_type_combination_id(RestVal...) << 8 | ((std::uint64_t)FirstVal);
        }

        class mem_mgr
        {
            mem_mgr()
            {
                // Reserved address space, no real memory allocation happens here.
#if defined(__linux__)
                mapped_address_space =
                    (byte_t *)mmap(nullptr, mapped_region_size, PROT_NONE,
                                   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
#elif defined(_WIN64)
                mapped_address_space = (byte_t *)VirtualAlloc(
                    NULL,               // NULL specified as the base address parameter
                    mapped_region_size, // Size of allocation
                    MEM_RESERVE,        // Allocate reserved pages
                    PAGE_NOACCESS);     // Protection = no access
#else
#error "Only support Windows and Linux."
#endif
                next_free = mapped_address_space;
            }

        public:
            using buffer_id_t = int;

            struct allocation
            {
                buffer_t buffer;
                byte_t *alloc_ptr;
                size_t size;
            };

            ~mem_mgr()
            {
#if defined(__linux__)
                munmap(mapped_address_space, mapped_region_size);
#elif defined(_WIN64)
                VirtualFree(mapped_address_space, 0, MEM_RELEASE);
#else
#error "Only support Windows and Linux."
#endif
            }

            mem_mgr(const mem_mgr &) = delete;
            mem_mgr &operator=(const mem_mgr &) = delete;
            mem_mgr(mem_mgr &&) = delete;
            mem_mgr &operator=(mem_mgr &&) = delete;

            /// Allocate
            void *mem_alloc(size_t size)
            {
                if (!size)
                    return nullptr;
                std::lock_guard<std::mutex> lock(m_mutex);
                if (next_free + size > mapped_address_space + mapped_region_size)
                {
                    throw std::runtime_error("dpct_malloc: out of memory for virtual memory pool");
                }
                // Allocation
                sycl::range<1> r(size);
                buffer_t buf(r);
                allocation A{buf, next_free, size};
                // Map allocation to device pointer
                void *result = next_free;
                m_map.emplace(next_free + size, A);
                // Update pointer to the next free space.
                next_free += (size + extra_padding + alignment - 1) & ~(alignment - 1);

                return result;
            }

            /// Deallocate
            void mem_free(const void *ptr)
            {
                if (!ptr)
                    return;
                std::lock_guard<std::mutex> lock(m_mutex);
                auto it = get_map_iterator(ptr);
                m_map.erase(it);
            }

            /// map: device pointer -> allocation(buffer, alloc_ptr, size)
            allocation translate_ptr(const void *ptr)
            {
                std::lock_guard<std::mutex> lock(m_mutex);
                auto it = get_map_iterator(ptr);
                return it->second;
            }

            /// Check if the pointer represents device pointer or not.
            bool is_device_ptr(const void *ptr) const
            {
                std::lock_guard<std::mutex> lock(m_mutex);
                return (mapped_address_space <= ptr) &&
                       (ptr < mapped_address_space + mapped_region_size);
            }

            /// Returns the instance of memory manager singleton.
            static mem_mgr &instance()
            {
                static mem_mgr m;
                return m;
            }

        private:
            std::map<byte_t *, allocation> m_map;
            mutable std::mutex m_mutex;
            byte_t *mapped_address_space;
            byte_t *next_free;
            const size_t mapped_region_size = 128ull * 1024 * 1024 * 1024;
            const size_t alignment = 256;
            /// This padding may be defined to some positive value to debug
            /// out of bound accesses.
            const size_t extra_padding = 0;

            std::map<byte_t *, allocation>::iterator get_map_iterator(const void *ptr)
            {
                auto it = m_map.upper_bound((byte_t *)ptr);
                if (it == m_map.end())
                {
                    // Not a virtual pointer.
                    throw std::runtime_error("can not get buffer from non-virtual pointer");
                }
                const allocation &alloc = it->second;
                if (ptr < alloc.alloc_ptr)
                {
                    // Out of bound.
                    // This may happen if there's a gap between allocations due to alignment
                    // or extra padding and pointer points to this gap.
                    throw std::runtime_error("invalid virtual pointer");
                }
                return it;
            }
        };

        template <class T, memory_region Memory, size_t Dimension>
        class accessor;
        template <memory_region Memory, class T = byte_t>
        class memory_traits
        {
        public:
            static constexpr sycl::access::target target =
                sycl::access::target::device;
            static constexpr sycl::access_mode mode =
                (Memory == constant) ? sycl::access_mode::read
                                     : sycl::access_mode::read_write;
            static constexpr size_t type_size = sizeof(T);
            using element_t =
                typename std::conditional<Memory == constant, const T, T>::type;
            using value_t = typename std::remove_cv<T>::type;
            template <size_t Dimension = 1>
            using accessor_t = typename std::conditional<
                Memory == local, sycl::local_accessor<value_t, Dimension>,
                sycl::accessor<T, Dimension, mode, target>>::type;
            using pointer_t = T *;
        };

        static inline void *dpct_malloc(size_t size, sycl::queue &q)
        {
            return sycl::malloc_device(size, q.get_device(), q.get_context());
        }

#define PITCH_DEFAULT_ALIGN(x) (((x) + 31) & ~(0x1F))
        static inline void *dpct_malloc(size_t &pitch, size_t x, size_t y, size_t z,
                                        sycl::queue &q)
        {
            pitch = PITCH_DEFAULT_ALIGN(x);
            return dpct_malloc(pitch * y * z, q);
        }

        /**
         * @brief Sets \p value to the first \p size elements starting from \p dev_ptr in \p q.
         * @tparam valueT The type of the element to be set.
         * @param [in] q The queue in which the operation is done.
         * @param [in] dev_ptr Pointer to the virtual device memory address.
         * @param [in] value The value to be set.
         * @param [in] size Number of elements to be set to the value.
         * @return An event representing the memset operation.
         */
        template <typename valueT>
        static inline sycl::event dpct_memset(sycl::queue &q, void *dev_ptr,
                                              valueT value, size_t size)
        {
            return q.fill(dev_ptr, value, size);
        }

        /**
         * @brief Sets \p value to the 3D memory region pointed by \p data in \p q.
         * @tparam valueT The type of the element to be set.
         * @param [in] q The queue in which the operation is done.
         * @param [in] data Pointer to the pitched device memory region.
         * @param [in] value The value to be set.
         * @param [in] size 3D memory region by number of elements.
         * @return An event list representing the memset operations.
         */
        template <typename valueT>
        static inline std::vector<sycl::event>
        dpct_memset(sycl::queue &q, pitched_data data, valueT value,
                    sycl::range<3> size)
        {
            std::vector<sycl::event> event_list;
            size_t slice = data.get_pitch() * data.get_y();
            unsigned char *data_surface = (unsigned char *)data.get_data_ptr();
            for (size_t z = 0; z < size.get(2); ++z)
            {
                unsigned char *data_ptr = data_surface;
                for (size_t y = 0; y < size.get(1); ++y)
                {
                    event_list.push_back(dpct_memset(q, data_ptr, value, size.get(0)));
                    data_ptr += data.get_pitch();
                }
                data_surface += slice;
            }
            return event_list;
        }

        /**
         * @brief Sets \p val to the pitched 2D memory region pointed by \p ptr in \p q.
         * @tparam valueT The type of the element to be set.
         * @param [in] q The queue in which the operation is done.
         * @param [in] ptr Pointer to the virtual device memory.
         * @param [in] pitch The pitch size by number of elements, including padding.
         * @param [in] val The value to be set.
         * @param [in] x The width of memory region by number of elements.
         * @param [in] y The height of memory region by number of elements.
         * @return An event list representing the memset operations.
         */
        template <typename valueT>
        static inline std::vector<sycl::event>
        dpct_memset(sycl::queue &q, void *ptr, size_t pitch, valueT val, size_t x,
                    size_t y)
        {
            return dpct_memset(q, pitched_data(ptr, pitch, x, 1), val,
                               sycl::range<3>(x, y, 1));
        }

        static memcpy_direction deduce_memcpy_direction(sycl::queue &q, void *to_ptr,
                                                        const void *from_ptr,
                                                        memcpy_direction dir)
        {
            switch (dir)
            {
            case memcpy_direction::host_to_host:
            case memcpy_direction::host_to_device:
            case memcpy_direction::device_to_host:
            case memcpy_direction::device_to_device:
                return dir;
            case memcpy_direction::automatic:
            {
                // table[to_attribute][from_attribute]
                static const memcpy_direction
                    direction_table[static_cast<unsigned>(pointer_access_attribute::end)]
                                   [static_cast<unsigned>(pointer_access_attribute::end)] =
                                       {{memcpy_direction::host_to_host,
                                         memcpy_direction::device_to_host,
                                         memcpy_direction::host_to_host},
                                        {memcpy_direction::host_to_device,
                                         memcpy_direction::device_to_device,
                                         memcpy_direction::device_to_device},
                                        {memcpy_direction::host_to_host,
                                         memcpy_direction::device_to_device,
                                         memcpy_direction::device_to_device}};
                return direction_table[static_cast<unsigned>(get_pointer_attribute(
                    q, to_ptr))][static_cast<unsigned>(get_pointer_attribute(q, from_ptr))];
            }
            default:
                throw std::runtime_error("dpct_memcpy: invalid direction value");
            }
        }

        static sycl::event
        dpct_memcpy(sycl::queue &q, void *to_ptr, const void *from_ptr, size_t size,
                    memcpy_direction direction,
                    const std::vector<sycl::event> &dep_events = {})
        {
            if (!size)
                return sycl::event{};
            return q.memcpy(to_ptr, from_ptr, size, dep_events);
            GGML_UNUSED(direction);
        }

        // Get actual copy range and make sure it will not exceed range.
        static inline size_t get_copy_range(sycl::range<3> size, size_t slice,
                                            size_t pitch)
        {
            return slice * (size.get(2) - 1) + pitch * (size.get(1) - 1) + size.get(0);
        }

        static inline size_t get_offset(sycl::id<3> id, size_t slice,
                                        size_t pitch)
        {
            return slice * id.get(2) + pitch * id.get(1) + id.get(0);
        }

        /// copy 3D matrix specified by \p size from 3D matrix specified by \p from_ptr
        /// and \p from_range to another specified by \p to_ptr and \p to_range.
        static inline std::vector<sycl::event>
        dpct_memcpy(sycl::queue &q, void *to_ptr, const void *from_ptr,
                    sycl::range<3> to_range, sycl::range<3> from_range,
                    sycl::id<3> to_id, sycl::id<3> from_id,
                    sycl::range<3> size, memcpy_direction direction,
                    const std::vector<sycl::event> &dep_events = {})
        {
            // RAII for host pointer
            class host_buffer
            {
                void *_buf;
                size_t _size;
                sycl::queue &_q;
                const std::vector<sycl::event> &_deps; // free operation depends

            public:
                host_buffer(size_t size, sycl::queue &q,
                            const std::vector<sycl::event> &deps)
                    : _buf(std::malloc(size)), _size(size), _q(q), _deps(deps) {}
                void *get_ptr() const { return _buf; }
                size_t get_size() const { return _size; }
                ~host_buffer()
                {
                    if (_buf)
                    {
                        _q.submit([&](sycl::handler &cgh)
                                  {
        cgh.depends_on(_deps);
        cgh.host_task([buf = _buf] { std::free(buf); }); });
                    }
                }
            };
            std::vector<sycl::event> event_list;

            size_t to_slice = to_range.get(1) * to_range.get(0),
                   from_slice = from_range.get(1) * from_range.get(0);
            unsigned char *to_surface =
                (unsigned char *)to_ptr + get_offset(to_id, to_slice, to_range.get(0));
            const unsigned char *from_surface =
                (const unsigned char *)from_ptr +
                get_offset(from_id, from_slice, from_range.get(0));

            if (to_slice == from_slice && to_slice == size.get(1) * size.get(0))
            {
                return {dpct_memcpy(q, to_surface, from_surface, to_slice * size.get(2),
                                    direction, dep_events)};
            }
            direction = deduce_memcpy_direction(q, to_ptr, from_ptr, direction);
            size_t size_slice = size.get(1) * size.get(0);
            switch (direction)
            {
            case host_to_host:
                for (size_t z = 0; z < size.get(2); ++z)
                {
                    unsigned char *to_ptr = to_surface;
                    const unsigned char *from_ptr = from_surface;
                    if (to_range.get(0) == from_range.get(0) &&
                        to_range.get(0) == size.get(0))
                    {
                        event_list.push_back(dpct_memcpy(q, to_ptr, from_ptr, size_slice,
                                                         direction, dep_events));
                    }
                    else
                    {
                        for (size_t y = 0; y < size.get(1); ++y)
                        {
                            event_list.push_back(dpct_memcpy(q, to_ptr, from_ptr, size.get(0),
                                                             direction, dep_events));
                            to_ptr += to_range.get(0);
                            from_ptr += from_range.get(0);
                        }
                    }
                    to_surface += to_slice;
                    from_surface += from_slice;
                }
                break;
            case host_to_device:
            {
                host_buffer buf(get_copy_range(size, to_slice, to_range.get(0)), q,
                                event_list);
                std::vector<sycl::event> host_events;
                if (to_slice == size_slice)
                {
                    // Copy host data to a temp host buffer with the shape of target.
                    host_events =
                        dpct_memcpy(q, buf.get_ptr(), from_surface, to_range, from_range,
                                    sycl::id<3>(0, 0, 0), sycl::id<3>(0, 0, 0), size,
                                    host_to_host, dep_events);
                }
                else
                {
                    // Copy host data to a temp host buffer with the shape of target.
                    host_events = dpct_memcpy(
                        q, buf.get_ptr(), from_surface, to_range, from_range,
                        sycl::id<3>(0, 0, 0), sycl::id<3>(0, 0, 0), size, host_to_host,
                        // If has padding data, not sure whether it is useless. So fill temp
                        // buffer with it.
                        std::vector<sycl::event>{
                            dpct_memcpy(q, buf.get_ptr(), to_surface, buf.get_size(),
                                        device_to_host, dep_events)});
                }
                // Copy from temp host buffer to device with only one submit.
                event_list.push_back(dpct_memcpy(q, to_surface, buf.get_ptr(),
                                                 buf.get_size(), host_to_device,
                                                 host_events));
                break;
            }
            case device_to_host:
            {
                host_buffer buf(get_copy_range(size, from_slice, from_range.get(0)), q,
                                event_list);
                // Copy from host temp buffer to host target with reshaping.
                event_list = dpct_memcpy(
                    q, to_surface, buf.get_ptr(), to_range, from_range, sycl::id<3>(0, 0, 0),
                    sycl::id<3>(0, 0, 0), size, host_to_host,
                    // Copy from device to temp host buffer with only one submit.
                    std::vector<sycl::event>{dpct_memcpy(q, buf.get_ptr(), from_surface,
                                                         buf.get_size(),
                                                         device_to_host, dep_events)});
                break;
            }
            case device_to_device:
                event_list.push_back(q.submit([&](sycl::handler &cgh){
                cgh.depends_on(dep_events);
                cgh.parallel_for<class dpct_memcpy_3d_detail>(
                    size,
                    [=](sycl::id<3> id) {
                        to_surface[get_offset(id, to_slice, to_range.get(0))] =
                            from_surface[get_offset(id, from_slice, from_range.get(0))];
                    }); }));
                break;
            default:
                throw std::runtime_error("dpct_memcpy: invalid direction value");
            }
            return event_list;
        }

        /// memcpy 2D/3D matrix specified by pitched_data.
        static inline std::vector<sycl::event>
        dpct_memcpy(sycl::queue &q, pitched_data to, sycl::id<3> to_id,
                    pitched_data from, sycl::id<3> from_id, sycl::range<3> size,
                    memcpy_direction direction = automatic)
        {
            return dpct_memcpy(q, to.get_data_ptr(), from.get_data_ptr(),
                               sycl::range<3>(to.get_pitch(), to.get_y(), 1),
                               sycl::range<3>(from.get_pitch(), from.get_y(), 1), to_id, from_id,
                               size, direction);
        }

        /// memcpy 2D matrix with pitch.
        static inline std::vector<sycl::event>
        dpct_memcpy(sycl::queue &q, void *to_ptr, const void *from_ptr,
                    size_t to_pitch, size_t from_pitch, size_t x, size_t y,
                    memcpy_direction direction = automatic)
        {
            return dpct_memcpy(q, to_ptr, from_ptr, sycl::range<3>(to_pitch, y, 1),
                               sycl::range<3>(from_pitch, y, 1),
                               sycl::id<3>(0, 0, 0), sycl::id<3>(0, 0, 0),
                               sycl::range<3>(x, y, 1), direction);
        }

        namespace deprecated
        {

            template <typename T, sycl::usm::alloc AllocKind>
            class usm_allocator
            {
            private:
                using Alloc = sycl::usm_allocator<T, AllocKind>;
                Alloc _impl;

            public:
                using value_type = typename std::allocator_traits<Alloc>::value_type;
                using pointer = typename std::allocator_traits<Alloc>::pointer;
                using const_pointer = typename std::allocator_traits<Alloc>::const_pointer;
                using void_pointer = typename std::allocator_traits<Alloc>::void_pointer;
                using const_void_pointer =
                    typename std::allocator_traits<Alloc>::const_void_pointer;
                using reference = typename std::allocator_traits<Alloc>::value_type &;
                using const_reference =
                    const typename std::allocator_traits<Alloc>::value_type &;
                using difference_type =
                    typename std::allocator_traits<Alloc>::difference_type;
                using size_type = typename std::allocator_traits<Alloc>::size_type;
                using propagate_on_container_copy_assignment = typename std::allocator_traits<
                    Alloc>::propagate_on_container_copy_assignment;
                using propagate_on_container_move_assignment = typename std::allocator_traits<
                    Alloc>::propagate_on_container_move_assignment;
                using propagate_on_container_swap =
                    typename std::allocator_traits<Alloc>::propagate_on_container_swap;
                using is_always_equal =
                    typename std::allocator_traits<Alloc>::is_always_equal;

                template <typename U>
                struct rebind
                {
                    typedef usm_allocator<U, AllocKind> other;
                };

                usm_allocator() : _impl(dpct::get_default_queue()) {}
                ~usm_allocator() {}
                usm_allocator(const usm_allocator &other) : _impl(other._impl) {}
                usm_allocator(usm_allocator &&other) : _impl(std::move(other._impl)) {}
                pointer address(reference r) { return &r; }
                const_pointer address(const_reference r) { return &r; }
                pointer allocate(size_type cnt, const_void_pointer hint = nullptr)
                {
                    return std::allocator_traits<Alloc>::allocate(_impl, cnt, hint);
                }
                void deallocate(pointer p, size_type cnt)
                {
                    std::allocator_traits<Alloc>::deallocate(_impl, p, cnt);
                }
                size_type max_size() const
                {
                    return std::allocator_traits<Alloc>::max_size(_impl);
                }
                bool operator==(const usm_allocator &other) const { return _impl == other._impl; }
                bool operator!=(const usm_allocator &other) const { return _impl != other._impl; }
            };

        } // namespace deprecated

        inline void dpct_free(void *ptr,
                              const sycl::queue &q)
        {
            if (ptr)
            {
                sycl::free(ptr, q.get_context());
            }
        }

        template <typename T>
        inline auto get_memory(const void *x)
        {
            T *new_x = reinterpret_cast<T *>(const_cast<void *>(x));
            return new_x;
        }

        template <typename T>
        inline typename DataType<T>::T2 get_value(const T *s, sycl::queue &q)
        {
            using Ty = typename DataType<T>::T2;
            Ty s_h;
            if (get_pointer_attribute(q, s) == pointer_access_attribute::device_only)
                detail::dpct_memcpy(q, (void *)&s_h, (const void *)s, sizeof(T), device_to_host)
                    .wait();
            else
                s_h = *reinterpret_cast<const Ty *>(s);
            return s_h;
        }

    } // namespace detail

    template <typename T>
    inline auto get_value(const T *s, sycl::queue &q)
    {
        return detail::get_value(s, q);
    }

    namespace detail
    {
        template <class Ta, class Tb, class Tc, class Ts>
        inline void gemm_impl(sycl::queue &q, oneapi::mkl::transpose a_trans,
                              oneapi::mkl::transpose b_trans, int m, int n, int k,
                              const void *alpha, const void *a, int lda, const void *b,
                              int ldb, const void *beta, void *c, int ldc)
        {
            Ts alpha_value = dpct::get_value(reinterpret_cast<const Ts *>(alpha), q);
            Ts beta_value = dpct::get_value(reinterpret_cast<const Ts *>(beta), q);
            auto data_a = get_memory<const Ta>(a);
            auto data_b = get_memory<const Tb>(b);
            auto data_c = get_memory<Tc>(c);
            oneapi::mkl::blas::column_major::gemm(
                q, a_trans, b_trans, m, n, k, alpha_value, data_a, lda,
                data_b, ldb, beta_value, data_c, ldc);
        }

        template <typename VecT, class BinaryOperation, class = void>
        class vectorized_binary
        {
        public:
            inline VecT operator()(VecT a, VecT b, const BinaryOperation binary_op)
            {
                VecT v4;
                for (size_t i = 0; i < v4.size(); ++i)
                {
                    v4[i] = binary_op(a[i], b[i]);
                }
                return v4;
            }
        };

        template <typename VecT, class BinaryOperation>
        class vectorized_binary<
            VecT, BinaryOperation,
            std::void_t<std::invoke_result_t<BinaryOperation, VecT, VecT>>>
        {
        public:
            inline VecT operator()(VecT a, VecT b, const BinaryOperation binary_op)
            {
                return binary_op(a, b).template as<VecT>();
            }
        };

        template <class Ta, class Tb, class Tc, class Ts>
        inline void gemm_batch_impl(sycl::queue &q, oneapi::mkl::transpose a_trans,
                                    oneapi::mkl::transpose b_trans, int m, int n, int k,
                                    const void *alpha, const void **a, int lda,
                                    const void **b, int ldb, const void *beta, void **c,
                                    int ldc, int batch_size)
        {
            struct matrix_info_t
            {
                oneapi::mkl::transpose transpose_info[2];
                Ts value_info[2];
                std::int64_t size_info[3];
                std::int64_t ld_info[3];
                std::int64_t groupsize_info;
            };

            Ts alpha_value = dpct::get_value(reinterpret_cast<const Ts *>(alpha), q);
            Ts beta_value = dpct::get_value(reinterpret_cast<const Ts *>(beta), q);

            matrix_info_t *matrix_info =
                (matrix_info_t *)std::malloc(sizeof(matrix_info_t));
            matrix_info->transpose_info[0] = a_trans;
            matrix_info->transpose_info[1] = b_trans;
            matrix_info->value_info[0] = alpha_value;
            matrix_info->value_info[1] = beta_value;
            matrix_info->size_info[0] = m;
            matrix_info->size_info[1] = n;
            matrix_info->size_info[2] = k;
            matrix_info->ld_info[0] = lda;
            matrix_info->ld_info[1] = ldb;
            matrix_info->ld_info[2] = ldc;
            matrix_info->groupsize_info = batch_size;

            sycl::event e = oneapi::mkl::blas::column_major::gemm_batch(
                q, matrix_info->transpose_info, matrix_info->transpose_info + 1,
                matrix_info->size_info, matrix_info->size_info + 1,
                matrix_info->size_info + 2, matrix_info->value_info,
                reinterpret_cast<const Ta **>(a), matrix_info->ld_info,
                reinterpret_cast<const Tb **>(b), matrix_info->ld_info + 1,
                matrix_info->value_info + 1, reinterpret_cast<Tc **>(c),
                matrix_info->ld_info + 2, 1, &(matrix_info->groupsize_info));

            q.submit([&](sycl::handler &cgh)
                     {
    cgh.depends_on(e);
    cgh.host_task([=] { std::free(matrix_info); }); });
        }

        template <class Ta, class Tb, class Tc, class Ts>
        inline void
        gemm_batch_impl(sycl::queue &q, oneapi::mkl::transpose a_trans,
                        oneapi::mkl::transpose b_trans, int m, int n,
                        int k, const void *alpha, const void *a, int lda,
                        long long int stride_a, const void *b, int ldb,
                        long long int stride_b, const void *beta, void *c,
                        int ldc, long long int stride_c, int batch_size)
        {
            Ts alpha_value = dpct::get_value(reinterpret_cast<const Ts *>(alpha), q);
            Ts beta_value = dpct::get_value(reinterpret_cast<const Ts *>(beta), q);
            auto data_a = get_memory<const Ta>(a);
            auto data_b = get_memory<const Tb>(b);
            auto data_c = get_memory<Tc>(c);
            oneapi::mkl::blas::column_major::gemm_batch(
                q, a_trans, b_trans, m, n, k, alpha_value, data_a, lda,
                stride_a, data_b, ldb, stride_b, beta_value,
                data_c, ldc, stride_c, batch_size);
        }

    } // namespace detail

    template <typename VecT, class BinaryOperation>
    inline unsigned vectorized_binary(unsigned a, unsigned b,
                                      const BinaryOperation binary_op)
    {
        sycl::vec<unsigned, 1> v0{a}, v1{b};
        auto v2 = v0.as<VecT>();
        auto v3 = v1.as<VecT>();
        auto v4 =
            detail::vectorized_binary<VecT, BinaryOperation>()(v2, v3, binary_op);
        v0 = v4.template as<sycl::vec<unsigned, 1>>();
        return v0;
    }

    static void async_dpct_memcpy(void *to_ptr, const void *from_ptr, size_t size,
                                  memcpy_direction direction = automatic,
                                  sycl::queue &q = dpct::get_default_queue())
    {
        detail::dpct_memcpy(q, to_ptr, from_ptr, size, direction);
    }

    static inline unsigned int select_device(unsigned int id)
    {
        dev_mgr::instance().select_device(id);
        return id;
    }

    template <typename T>
    T permute_sub_group_by_xor(sycl::sub_group g, T x, unsigned int mask,
                               unsigned int logical_sub_group_size = 32)
    {
        unsigned int id = g.get_local_linear_id();
        unsigned int start_index =
            id / logical_sub_group_size * logical_sub_group_size;
        unsigned int target_offset = (id % logical_sub_group_size) ^ mask;
        return sycl::select_from_group(g, x,
                                       target_offset < logical_sub_group_size
                                           ? start_index + target_offset
                                           : id);
    }

    template <typename T>
    sycl::vec<T, 4> extract_and_sign_or_zero_extend4(T val)
    {
        return sycl::vec<T, 1>(val)
            .template as<sycl::vec<
                std::conditional_t<std::is_signed_v<T>, int8_t, uint8_t>, 4>>()
            .template convert<T>();
    }

    template <typename T1, typename T2>
    using dot_product_acc_t =
        std::conditional_t<std::is_unsigned_v<T1> && std::is_unsigned_v<T2>,
                           uint32_t, int32_t>;

    template <typename T1, typename T2, typename T3>
    inline auto dp4a(T1 a, T2 b, T3 c)
    {
        dot_product_acc_t<T1, T2> res = c;
        auto va = extract_and_sign_or_zero_extend4(a);
        auto vb = extract_and_sign_or_zero_extend4(b);
        res += va[0] * vb[0];
        res += va[1] * vb[1];
        res += va[2] * vb[2];
        res += va[3] * vb[3];
        return res;
    }

    struct sub_sat
    {
        template <typename T>
        auto operator()(const T x, const T y) const
        {
            return sycl::sub_sat(x, y);
        }
    };

    template <typename S, typename T>
    inline T vectorized_min(T a, T b)
    {
        sycl::vec<T, 1> v0{a}, v1{b};
        auto v2 = v0.template as<S>();
        auto v3 = v1.template as<S>();
        auto v4 = sycl::min(v2, v3);
        v0 = v4.template as<sycl::vec<T, 1>>();
        return v0;
    }

    inline float pow(const float a, const int b) { return sycl::pown(a, b); }
    inline double pow(const double a, const int b) { return sycl::pown(a, b); }
    inline float pow(const float a, const float b) { return sycl::pow(a, b); }
    inline double pow(const double a, const double b) { return sycl::pow(a, b); }
    template <typename T, typename U>
    inline typename std::enable_if_t<std::is_floating_point_v<T>, T>
    pow(const T a, const U b)
    {
        return sycl::pow(a, static_cast<T>(b));
    }
    template <typename T, typename U>
    inline typename std::enable_if_t<!std::is_floating_point_v<T>, double>
    pow(const T a, const U b)
    {
        return sycl::pow(static_cast<double>(a), static_cast<double>(b));
    }

    inline double min(const double a, const float b)
    {
        return sycl::fmin(a, static_cast<double>(b));
    }
    inline double min(const float a, const double b)
    {
        return sycl::fmin(static_cast<double>(a), b);
    }
    inline float min(const float a, const float b) { return sycl::fmin(a, b); }
    inline double min(const double a, const double b) { return sycl::fmin(a, b); }
    inline std::uint32_t min(const std::uint32_t a, const std::int32_t b)
    {
        return sycl::min(a, static_cast<std::uint32_t>(b));
    }
    inline std::uint32_t min(const std::int32_t a, const std::uint32_t b)
    {
        return sycl::min(static_cast<std::uint32_t>(a), b);
    }
    inline std::int32_t min(const std::int32_t a, const std::int32_t b)
    {
        return sycl::min(a, b);
    }
    inline std::uint32_t min(const std::uint32_t a, const std::uint32_t b)
    {
        return sycl::min(a, b);
    }
    inline std::uint64_t min(const std::uint64_t a, const std::int64_t b)
    {
        return sycl::min(a, static_cast<std::uint64_t>(b));
    }
    inline std::uint64_t min(const std::int64_t a, const std::uint64_t b)
    {
        return sycl::min(static_cast<std::uint64_t>(a), b);
    }
    inline std::int64_t min(const std::int64_t a, const std::int64_t b)
    {
        return sycl::min(a, b);
    }
    inline std::uint64_t min(const std::uint64_t a, const std::uint64_t b)
    {
        return sycl::min(a, b);
    }
    inline std::uint64_t min(const std::uint64_t a, const std::int32_t b)
    {
        return sycl::min(a, static_cast<std::uint64_t>(b));
    }
    inline std::uint64_t min(const std::int32_t a, const std::uint64_t b)
    {
        return sycl::min(static_cast<std::uint64_t>(a), b);
    }
    inline std::uint64_t min(const std::uint64_t a, const std::uint32_t b)
    {
        return sycl::min(a, static_cast<std::uint64_t>(b));
    }
    inline std::uint64_t min(const std::uint32_t a, const std::uint64_t b)
    {
        return sycl::min(static_cast<std::uint64_t>(a), b);
    }
    // max function overloads.
    // For floating-point types, `float` or `double` arguments are acceptable.
    // For integer types, `std::uint32_t`, `std::int32_t`, `std::uint64_t` or
    // `std::int64_t` type arguments are acceptable.
    inline double max(const double a, const float b)
    {
        return sycl::fmax(a, static_cast<double>(b));
    }
    inline double max(const float a, const double b)
    {
        return sycl::fmax(static_cast<double>(a), b);
    }
    inline float max(const float a, const float b) { return sycl::fmax(a, b); }
    inline double max(const double a, const double b) { return sycl::fmax(a, b); }
    inline std::uint32_t max(const std::uint32_t a, const std::int32_t b)
    {
        return sycl::max(a, static_cast<std::uint32_t>(b));
    }
    inline std::uint32_t max(const std::int32_t a, const std::uint32_t b)
    {
        return sycl::max(static_cast<std::uint32_t>(a), b);
    }
    inline std::int32_t max(const std::int32_t a, const std::int32_t b)
    {
        return sycl::max(a, b);
    }
    inline std::uint32_t max(const std::uint32_t a, const std::uint32_t b)
    {
        return sycl::max(a, b);
    }
    inline std::uint64_t max(const std::uint64_t a, const std::int64_t b)
    {
        return sycl::max(a, static_cast<std::uint64_t>(b));
    }
    inline std::uint64_t max(const std::int64_t a, const std::uint64_t b)
    {
        return sycl::max(static_cast<std::uint64_t>(a), b);
    }
    inline std::int64_t max(const std::int64_t a, const std::int64_t b)
    {
        return sycl::max(a, b);
    }
    inline std::uint64_t max(const std::uint64_t a, const std::uint64_t b)
    {
        return sycl::max(a, b);
    }
    inline std::uint64_t max(const std::uint64_t a, const std::int32_t b)
    {
        return sycl::max(a, static_cast<std::uint64_t>(b));
    }
    inline std::uint64_t max(const std::int32_t a, const std::uint64_t b)
    {
        return sycl::max(static_cast<std::uint64_t>(a), b);
    }
    inline std::uint64_t max(const std::uint64_t a, const std::uint32_t b)
    {
        return sycl::max(a, static_cast<std::uint64_t>(b));
    }
    inline std::uint64_t max(const std::uint32_t a, const std::uint64_t b)
    {
        return sycl::max(static_cast<std::uint64_t>(a), b);
    }

    inline void
    has_capability_or_fail(const sycl::device &dev,
                           const std::initializer_list<sycl::aspect> &props)
    {
        for (const auto &it : props)
        {
            if (dev.has(it))
                continue;
            switch (it)
            {
            case sycl::aspect::fp64:
                throw std::runtime_error("'double' is not supported in '" +
                                         dev.get_info<sycl::info::device::name>() +
                                         "' device");
                break;
            case sycl::aspect::fp16:
                throw std::runtime_error("'half' is not supported in '" +
                                         dev.get_info<sycl::info::device::name>() +
                                         "' device");
                break;
            default:
#define __SYCL_ASPECT(ASPECT, ID) \
    case sycl::aspect::ASPECT:    \
        return #ASPECT;
#define __SYCL_ASPECT_DEPRECATED(ASPECT, ID, MESSAGE) __SYCL_ASPECT(ASPECT, ID)
#define __SYCL_ASPECT_DEPRECATED_ALIAS(ASPECT, ID, MESSAGE)
                auto getAspectNameStr = [](sycl::aspect AspectNum) -> std::string
                {
                    switch (AspectNum)
                    {
#include <sycl/info/aspects.def>
#include <sycl/info/aspects_deprecated.def>
                    default:
                        return "unknown aspect";
                    }
                };
#undef __SYCL_ASPECT_DEPRECATED_ALIAS
#undef __SYCL_ASPECT_DEPRECATED
#undef __SYCL_ASPECT
                throw std::runtime_error(
                    "'" + getAspectNameStr(it) + "' is not supported in '" +
                    dev.get_info<sycl::info::device::name>() + "' device");
            }
            break;
        }
    }

    static inline unsigned int get_current_device_id()
    {
        return dev_mgr::instance().current_device_id();
    }

    static inline device_ext &get_current_device()
    {
        return dev_mgr::instance().current_device();
    }

    static inline sycl::queue &get_in_order_queue()
    {
        return dev_mgr::instance().current_device().in_order_queue();
    }

    static sycl::event
    dpct_memcpy(sycl::queue &q, void *to_ptr, const void *from_ptr, size_t size,
                memcpy_direction direction,
                const std::vector<sycl::event> &dep_events = {})
    {
        if (!size)
            return sycl::event{};
        return q.memcpy(to_ptr, from_ptr, size, dep_events);
        GGML_UNUSED(direction);
    }

    // Get actual copy range and make sure it will not exceed range.
    static inline size_t get_copy_range(sycl::range<3> size, size_t slice,
                                        size_t pitch)
    {
        return slice * (size.get(2) - 1) + pitch * (size.get(1) - 1) + size.get(0);
    }

    static inline size_t get_offset(sycl::id<3> id, size_t slice,
                                    size_t pitch)
    {
        return slice * id.get(2) + pitch * id.get(1) + id.get(0);
    }

    /// copy 3D matrix specified by \p size from 3D matrix specified by \p from_ptr
    /// and \p from_range to another specified by \p to_ptr and \p to_range.
    static inline std::vector<sycl::event>
    dpct_memcpy(sycl::queue &q, void *to_ptr, const void *from_ptr,
                sycl::range<3> to_range, sycl::range<3> from_range,
                sycl::id<3> to_id, sycl::id<3> from_id,
                sycl::range<3> size, memcpy_direction direction,
                const std::vector<sycl::event> &dep_events = {})
    {
        // RAII for host pointer
        class host_buffer
        {
            void *_buf;
            size_t _size;
            sycl::queue &_q;
            const std::vector<sycl::event> &_deps; // free operation depends

        public:
            host_buffer(size_t size, sycl::queue &q,
                        const std::vector<sycl::event> &deps)
                : _buf(std::malloc(size)), _size(size), _q(q), _deps(deps) {}
            void *get_ptr() const { return _buf; }
            size_t get_size() const { return _size; }
            ~host_buffer()
            {
                if (_buf)
                {
                    _q.submit([&](sycl::handler &cgh)
                              {
            cgh.depends_on(_deps);
            cgh.host_task([buf = _buf] { std::free(buf); }); });
                }
            }
        };
        std::vector<sycl::event> event_list;

        size_t to_slice = to_range.get(1) * to_range.get(0),
               from_slice = from_range.get(1) * from_range.get(0);
        unsigned char *to_surface =
            (unsigned char *)to_ptr + get_offset(to_id, to_slice, to_range.get(0));
        const unsigned char *from_surface =
            (const unsigned char *)from_ptr +
            get_offset(from_id, from_slice, from_range.get(0));

        if (to_slice == from_slice && to_slice == size.get(1) * size.get(0))
        {
            return {dpct_memcpy(q, to_surface, from_surface, to_slice * size.get(2),
                                direction, dep_events)};
        }
        direction = detail::deduce_memcpy_direction(q, to_ptr, from_ptr, direction);
        size_t size_slice = size.get(1) * size.get(0);
        switch (direction)
        {
        case host_to_host:
            for (size_t z = 0; z < size.get(2); ++z)
            {
                unsigned char *to_ptr = to_surface;
                const unsigned char *from_ptr = from_surface;
                if (to_range.get(0) == from_range.get(0) &&
                    to_range.get(0) == size.get(0))
                {
                    event_list.push_back(dpct_memcpy(q, to_ptr, from_ptr, size_slice,
                                                     direction, dep_events));
                }
                else
                {
                    for (size_t y = 0; y < size.get(1); ++y)
                    {
                        event_list.push_back(dpct_memcpy(q, to_ptr, from_ptr, size.get(0),
                                                         direction, dep_events));
                        to_ptr += to_range.get(0);
                        from_ptr += from_range.get(0);
                    }
                }
                to_surface += to_slice;
                from_surface += from_slice;
            }
            break;
        case host_to_device:
        {
            host_buffer buf(get_copy_range(size, to_slice, to_range.get(0)), q,
                            event_list);
            std::vector<sycl::event> host_events;
            if (to_slice == size_slice)
            {
                // Copy host data to a temp host buffer with the shape of target.
                host_events =
                    dpct_memcpy(q, buf.get_ptr(), from_surface, to_range, from_range,
                                sycl::id<3>(0, 0, 0), sycl::id<3>(0, 0, 0), size,
                                host_to_host, dep_events);
            }
            else
            {
                // Copy host data to a temp host buffer with the shape of target.
                host_events = dpct_memcpy(
                    q, buf.get_ptr(), from_surface, to_range, from_range,
                    sycl::id<3>(0, 0, 0), sycl::id<3>(0, 0, 0), size, host_to_host,
                    // If has padding data, not sure whether it is useless. So fill temp
                    // buffer with it.
                    std::vector<sycl::event>{
                        dpct_memcpy(q, buf.get_ptr(), to_surface, buf.get_size(),
                                    device_to_host, dep_events)});
            }
            // Copy from temp host buffer to device with only one submit.
            event_list.push_back(dpct_memcpy(q, to_surface, buf.get_ptr(),
                                             buf.get_size(), host_to_device,
                                             host_events));
            break;
        }
        case device_to_host:
        {
            host_buffer buf(get_copy_range(size, from_slice, from_range.get(0)), q,
                            event_list);
            // Copy from host temp buffer to host target with reshaping.
            event_list = dpct_memcpy(
                q, to_surface, buf.get_ptr(), to_range, from_range, sycl::id<3>(0, 0, 0),
                sycl::id<3>(0, 0, 0), size, host_to_host,
                // Copy from device to temp host buffer with only one submit.
                std::vector<sycl::event>{dpct_memcpy(q, buf.get_ptr(), from_surface,
                                                     buf.get_size(),
                                                     device_to_host, dep_events)});
            break;
        }
        case device_to_device:
            event_list.push_back(q.submit([&](sycl::handler &cgh)
                                          {
        cgh.depends_on(dep_events);
        cgh.parallel_for<class dpct_memcpy_3d_detail>(
            size,
            [=](sycl::id<3> id) {
                to_surface[get_offset(id, to_slice, to_range.get(0))] =
                    from_surface[get_offset(id, from_slice, from_range.get(0))];
            }); }));
        break;
        default:
            throw std::runtime_error("dpct_memcpy: invalid direction value");
        }
        return event_list;
    }

    /// memcpy 2D/3D matrix specified by pitched_data.
    static inline std::vector<sycl::event>
    dpct_memcpy(sycl::queue &q, pitched_data to, sycl::id<3> to_id,
                pitched_data from, sycl::id<3> from_id, sycl::range<3> size,
                memcpy_direction direction = automatic)
    {
        return dpct_memcpy(q, to.get_data_ptr(), from.get_data_ptr(),
                           sycl::range<3>(to.get_pitch(), to.get_y(), 1),
                           sycl::range<3>(from.get_pitch(), from.get_y(), 1), to_id, from_id,
                           size, direction);
    }

    /// memcpy 2D matrix with pitch.
    static inline std::vector<sycl::event>
    dpct_memcpy(sycl::queue &q, void *to_ptr, const void *from_ptr,
                size_t to_pitch, size_t from_pitch, size_t x, size_t y,
                memcpy_direction direction = automatic)
    {
        return dpct_memcpy(q, to_ptr, from_ptr, sycl::range<3>(to_pitch, y, 1),
                           sycl::range<3>(from_pitch, y, 1),
                           sycl::id<3>(0, 0, 0), sycl::id<3>(0, 0, 0),
                           sycl::range<3>(x, y, 1), direction);
    }

    inline void gemm(sycl::queue &q, oneapi::mkl::transpose a_trans,
                     oneapi::mkl::transpose b_trans, int m, int n, int k,
                     const void *alpha, const void *a, library_data_t a_type,
                     int lda, const void *b, library_data_t b_type, int ldb,
                     const void *beta, void *c, library_data_t c_type, int ldc,
                     library_data_t scaling_type)
    {
        if (scaling_type == library_data_t::real_float &&
            c_type == library_data_t::complex_float)
        {
            scaling_type = library_data_t::complex_float;
        }
        else if (scaling_type == library_data_t::real_double &&
                 c_type == library_data_t::complex_double)
        {
            scaling_type = library_data_t::complex_double;
        }

        std::uint64_t key =
            detail::get_type_combination_id(a_type, b_type, c_type, scaling_type);
        switch (key)
        {
        case detail::get_type_combination_id(
            library_data_t::real_float, library_data_t::real_float,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_impl<float, float, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_double, library_data_t::real_double,
            library_data_t::real_double, library_data_t::real_double):
        {
            detail::gemm_impl<double, double, double, double>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::complex_float, library_data_t::complex_float,
            library_data_t::complex_float, library_data_t::complex_float):
        {
            detail::gemm_impl<std::complex<float>, std::complex<float>,
                              std::complex<float>, std::complex<float>>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::complex_double, library_data_t::complex_double,
            library_data_t::complex_double, library_data_t::complex_double):
        {
            detail::gemm_impl<std::complex<double>, std::complex<double>,
                              std::complex<double>, std::complex<double>>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_half, library_data_t::real_half):
        {
            detail::gemm_impl<sycl::half, sycl::half, sycl::half,
                              sycl::half>(q, a_trans, b_trans, m, n, k, alpha, a,
                                          lda, b, ldb, beta, c, ldc);
            break;
        }
#ifdef __INTEL_MKL__
        case detail::get_type_combination_id(
            library_data_t::real_bfloat16, library_data_t::real_bfloat16,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_impl<oneapi::mkl::bfloat16, oneapi::mkl::bfloat16, float,
                              float>(q, a_trans, b_trans, m, n, k, alpha, a, lda, b,
                                     ldb, beta, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_impl<sycl::half, sycl::half, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_half, library_data_t::real_float):
        {
            float alpha_value =
                dpct::get_value(reinterpret_cast<const float *>(alpha), q);
            float beta_value =
                dpct::get_value(reinterpret_cast<const float *>(beta), q);
            sycl::half alpha_half(alpha_value);
            sycl::half beta_half(beta_value);
            detail::gemm_impl<sycl::half, sycl::half, sycl::half,
                              sycl::half>(q, a_trans, b_trans, m, n, k, &alpha_half,
                                          a, lda, b, ldb, &beta_half, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_int8, library_data_t::real_int8,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_impl<std::int8_t, std::int8_t, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_bfloat16, library_data_t::real_bfloat16,
            library_data_t::real_bfloat16, library_data_t::real_float):
        {
            detail::gemm_impl<oneapi::mkl::bfloat16, oneapi::mkl::bfloat16,
                              oneapi::mkl::bfloat16, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_int8, library_data_t::real_int8,
            library_data_t::real_int32, library_data_t::real_int32):
        {
            float alpha_float =
                dpct::get_value(reinterpret_cast<const std::int32_t *>(alpha), q);
            float beta_float =
                dpct::get_value(reinterpret_cast<const std::int32_t *>(beta), q);
            detail::gemm_impl<std::int8_t, std::int8_t, std::int32_t, float>(
                q, a_trans, b_trans, m, n, k, &alpha_float, a, lda, b, ldb, &beta_float, c, ldc);
            break;
        }
#endif // __INTEL_MKL__
        default:
            throw std::runtime_error("the combination of data type is unsupported");
        }
    } // gemm()

    /// Computes a batch of matrix-matrix product with general matrices.
    /// \param [in] q The queue where the routine should be executed.
    /// \param [in] a_trans Specifies the operation applied to A.
    /// \param [in] b_trans Specifies the operation applied to B.
    /// \param [in] m Specifies the number of rows of the matrix op(A) and of the matrix C.
    /// \param [in] n Specifies the number of columns of the matrix op(B) and of the matrix C.
    /// \param [in] k Specifies the number of columns of the matrix op(A) and the number of rows of the matrix op(B).
    /// \param [in] alpha Scaling factor for the matrix-matrix product.
    /// \param [in] a Input matrix A.
    /// \param [in] a_type Data type of the matrix A.
    /// \param [in] lda Leading dimension of A.
    /// \param [in] b Input matrix B.
    /// \param [in] b_type Data type of the matrix B.
    /// \param [in] ldb Leading dimension of B.
    /// \param [in] beta Scaling factor for matrix C.
    /// \param [in, out] c Input/Output matrix C.
    /// \param [in] c_type Data type of the matrix C.
    /// \param [in] ldc Leading dimension of C.
    /// \param [in] batch_size Specifies the number of matrix multiply operations to perform.
    /// \param [in] scaling_type Data type of the scaling factors.
    inline void gemm_batch(sycl::queue &q, oneapi::mkl::transpose a_trans,
                           oneapi::mkl::transpose b_trans, int m, int n, int k,
                           const void *alpha, const void *a[],
                           library_data_t a_type, int lda, const void *b[],
                           library_data_t b_type, int ldb, const void *beta,
                           void *c[], library_data_t c_type, int ldc,
                           int batch_size, library_data_t scaling_type)
    {
        if (scaling_type == library_data_t::real_float &&
            c_type == library_data_t::complex_float)
        {
            scaling_type = library_data_t::complex_float;
        }
        else if (scaling_type == library_data_t::real_double &&
                 c_type == library_data_t::complex_double)
        {
            scaling_type = library_data_t::complex_double;
        }

        std::uint64_t key =
            detail::get_type_combination_id(a_type, b_type, c_type, scaling_type);
        switch (key)
        {
        case detail::get_type_combination_id(
            library_data_t::real_float, library_data_t::real_float,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_batch_impl<float, float, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc,
                batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_double, library_data_t::real_double,
            library_data_t::real_double, library_data_t::real_double):
        {
            detail::gemm_batch_impl<double, double, double, double>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc,
                batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::complex_float, library_data_t::complex_float,
            library_data_t::complex_float, library_data_t::complex_float):
        {
            detail::gemm_batch_impl<std::complex<float>, std::complex<float>,
                                    std::complex<float>, std::complex<float>>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc,
                batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::complex_double, library_data_t::complex_double,
            library_data_t::complex_double, library_data_t::complex_double):
        {
            detail::gemm_batch_impl<std::complex<double>, std::complex<double>,
                                    std::complex<double>, std::complex<double>>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc,
                batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_half, library_data_t::real_half):
        {
            detail::gemm_batch_impl<sycl::half, sycl::half, sycl::half,
                                    sycl::half>(q, a_trans, b_trans, m, n, k, alpha,
                                                a, lda, b, ldb, beta, c, ldc,
                                                batch_size);
            break;
        }
#ifdef __INTEL_MKL__
        case detail::get_type_combination_id(
            library_data_t::real_bfloat16, library_data_t::real_bfloat16,
            library_data_t::real_bfloat16, library_data_t::real_float):
        {
            detail::gemm_batch_impl<oneapi::mkl::bfloat16, oneapi::mkl::bfloat16,
                                    oneapi::mkl::bfloat16, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc,
                batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_bfloat16, library_data_t::real_bfloat16,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_batch_impl<oneapi::mkl::bfloat16, oneapi::mkl::bfloat16, float,
                                    float>(q, a_trans, b_trans, m, n, k, alpha, a, lda,
                                           b, ldb, beta, c, ldc, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_int8, library_data_t::real_int8,
            library_data_t::real_int32, library_data_t::real_int32):
        {
            float alpha_float =
                dpct::get_value(reinterpret_cast<const std::int32_t *>(alpha), q);
            float beta_float =
                dpct::get_value(reinterpret_cast<const std::int32_t *>(beta), q);
            detail::gemm_batch_impl<std::int8_t, std::int8_t, std::int32_t,
                                    float>(q, a_trans, b_trans, m, n, k, &alpha_float,
                                           a, lda, b, ldb, &beta_float, c, ldc,
                                           batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_int8, library_data_t::real_int8,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_batch_impl<std::int8_t, std::int8_t, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc,
                batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_batch_impl<sycl::half, sycl::half, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc,
                batch_size);
            break;
        }
#endif
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_half, library_data_t::real_float):
        {
            float alpha_value =
                dpct::get_value(reinterpret_cast<const float *>(alpha), q);
            float beta_value =
                dpct::get_value(reinterpret_cast<const float *>(beta), q);
            sycl::half alpha_half(alpha_value);
            sycl::half beta_half(beta_value);
            detail::gemm_batch_impl<sycl::half, sycl::half, sycl::half, sycl::half>(
                q, a_trans, b_trans, m, n, k, &alpha_half, a, lda, b, ldb, &beta_half, c, ldc,
                batch_size);
            break;
        }
        default:
            throw std::runtime_error("the combination of data type is unsupported");
        }
    }

    /// Computes a batch of matrix-matrix product with general matrices.
    /// \param [in] q The queue where the routine should be executed.
    /// \param [in] a_trans Specifies the operation applied to A.
    /// \param [in] b_trans Specifies the operation applied to B.
    /// \param [in] m Specifies the number of rows of the matrix op(A) and of the matrix C.
    /// \param [in] n Specifies the number of columns of the matrix op(B) and of the matrix C.
    /// \param [in] k Specifies the number of columns of the matrix op(A) and the number of rows of the matrix op(B).
    /// \param [in] alpha Scaling factor for the matrix-matrix product.
    /// \param [in] a Input matrix A.
    /// \param [in] a_type Data type of the matrix A.
    /// \param [in] lda Leading dimension of A.
    /// \param [in] stride_a Stride between the different A matrices.
    /// \param [in] b Input matrix B.
    /// \param [in] b_type Data type of the matrix B.
    /// \param [in] ldb Leading dimension of B.
    /// \param [in] stride_b Stride between the different B matrices.
    /// \param [in] beta Scaling factor for matrix C.
    /// \param [in, out] c Input/Output matrix C.
    /// \param [in] c_type Data type of the matrix C.
    /// \param [in] ldc Leading dimension of C.
    /// \param [in] stride_c Stride between the different C matrices.
    /// \param [in] batch_size Specifies the number of matrix multiply operations to perform.
    /// \param [in] scaling_type Data type of the scaling factors.
    inline void gemm_batch(sycl::queue &q, oneapi::mkl::transpose a_trans,
                           oneapi::mkl::transpose b_trans, int m, int n, int k,
                           const void *alpha, const void *a, library_data_t a_type,
                           int lda, long long int stride_a, const void *b,
                           library_data_t b_type, int ldb, long long int stride_b,
                           const void *beta, void *c, library_data_t c_type,
                           int ldc, long long int stride_c, int batch_size,
                           library_data_t scaling_type)
    {
        if (scaling_type == library_data_t::real_float &&
            c_type == library_data_t::complex_float)
        {
            scaling_type = library_data_t::complex_float;
        }
        else if (scaling_type == library_data_t::real_double &&
                 c_type == library_data_t::complex_double)
        {
            scaling_type = library_data_t::complex_double;
        }

        std::uint64_t key =
            detail::get_type_combination_id(a_type, b_type, c_type, scaling_type);
        switch (key)
        {
        case detail::get_type_combination_id(
            library_data_t::real_float, library_data_t::real_float,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_batch_impl<float, float, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, stride_a, b, ldb, stride_b,
                beta, c, ldc, stride_c, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_double, library_data_t::real_double,
            library_data_t::real_double, library_data_t::real_double):
        {
            detail::gemm_batch_impl<double, double, double, double>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, stride_a, b, ldb, stride_b,
                beta, c, ldc, stride_c, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::complex_float, library_data_t::complex_float,
            library_data_t::complex_float, library_data_t::complex_float):
        {
            detail::gemm_batch_impl<std::complex<float>, std::complex<float>,
                                    std::complex<float>, std::complex<float>>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, stride_a, b, ldb, stride_b,
                beta, c, ldc, stride_c, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::complex_double, library_data_t::complex_double,
            library_data_t::complex_double, library_data_t::complex_double):
        {
            detail::gemm_batch_impl<std::complex<double>, std::complex<double>,
                                    std::complex<double>, std::complex<double>>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, stride_a, b, ldb, stride_b,
                beta, c, ldc, stride_c, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_half, library_data_t::real_half):
        {
            detail::gemm_batch_impl<sycl::half, sycl::half, sycl::half,
                                    sycl::half>(q, a_trans, b_trans, m, n, k, alpha,
                                                a, lda, stride_a, b, ldb, stride_b,
                                                beta, c, ldc, stride_c, batch_size);
            break;
        }
#ifdef __INTEL_MKL__
        case detail::get_type_combination_id(
            library_data_t::real_bfloat16, library_data_t::real_bfloat16,
            library_data_t::real_bfloat16, library_data_t::real_float):
        {
            detail::gemm_batch_impl<oneapi::mkl::bfloat16, oneapi::mkl::bfloat16,
                                    oneapi::mkl::bfloat16, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, stride_a, b, ldb, stride_b,
                beta, c, ldc, stride_c, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_bfloat16, library_data_t::real_bfloat16,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_batch_impl<oneapi::mkl::bfloat16, oneapi::mkl::bfloat16, float,
                                    float>(q, a_trans, b_trans, m, n, k, alpha, a, lda,
                                           stride_a, b, ldb, stride_b, beta, c, ldc,
                                           stride_c, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_int8, library_data_t::real_int8,
            library_data_t::real_int32, library_data_t::real_int32):
        {
            detail::gemm_batch_impl<std::int8_t, std::int8_t, std::int32_t,
                                    std::int32_t>(q, a_trans, b_trans, m, n, k, alpha,
                                                  a, lda, stride_a, b, ldb, stride_b,
                                                  beta, c, ldc, stride_c, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_int8, library_data_t::real_int8,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_batch_impl<std::int8_t, std::int8_t, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, stride_a, b, ldb, stride_b,
                beta, c, ldc, stride_c, batch_size);
            break;
        }
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_float, library_data_t::real_float):
        {
            detail::gemm_batch_impl<sycl::half, sycl::half, float, float>(
                q, a_trans, b_trans, m, n, k, alpha, a, lda, stride_a, b, ldb, stride_b,
                beta, c, ldc, stride_c, batch_size);
            break;
        }
#endif
        case detail::get_type_combination_id(
            library_data_t::real_half, library_data_t::real_half,
            library_data_t::real_half, library_data_t::real_float):
        {
            float alpha_value =
                dpct::get_value(reinterpret_cast<const float *>(alpha), q);
            float beta_value =
                dpct::get_value(reinterpret_cast<const float *>(beta), q);
            sycl::half alpha_half(alpha_value);
            sycl::half beta_half(beta_value);
            detail::gemm_batch_impl<sycl::half, sycl::half, sycl::half, sycl::half>(
                q, a_trans, b_trans, m, n, k, &alpha_half, a, lda, stride_a, b, ldb, stride_b,
                &beta_half, c, ldc, stride_c, batch_size);
            break;
        }
        default:
            throw std::runtime_error("the combination of data type is unsupported");
        }
    }

    static inline void
    async_dpct_memcpy(void *to_ptr, size_t to_pitch, const void *from_ptr,
                      size_t from_pitch, size_t x, size_t y,
                      memcpy_direction direction = automatic,
                      sycl::queue &q = get_default_queue())
    {
        detail::dpct_memcpy(q, to_ptr, from_ptr, to_pitch, from_pitch, x, y,
                            direction);
    }

    using err0 = detail::generic_error_type<struct err0_tag, int>;
    using err1 = detail::generic_error_type<struct err1_tag, int>;

    static inline void dpct_free(void *ptr, sycl::queue &q = get_default_queue()) {
        detail::dpct_free(ptr, q);
    }

    /// dpct accessor used as device function parameter.
    template <class T, memory_region Memory, size_t Dimension> class accessor;
    template <class T, memory_region Memory> class accessor<T, Memory, 3> {
    public:
        using memory_t = detail::memory_traits<Memory, T>;
        using element_t = typename memory_t::element_t;
        using pointer_t = typename memory_t::pointer_t;
        using accessor_t = typename memory_t::template accessor_t<3>;
        accessor(pointer_t data, const sycl::range<3> &in_range)
            : _data(data), _range(in_range) {}
        template <memory_region M = Memory>
        accessor(typename std::enable_if<M != local, const accessor_t>::type &acc)
            : accessor(acc, acc.get_range()) {}
        accessor(const accessor_t &acc, const sycl::range<3> &in_range)
            : accessor(acc.get_pointer(), in_range) {}
        accessor<T, Memory, 2> operator[](size_t index) const {
            sycl::range<2> sub(_range.get(1), _range.get(2));
            return accessor<T, Memory, 2>(_data + index * sub.size(), sub);
        }

        pointer_t get_ptr() const { return _data; }

    private:
        pointer_t _data;
        sycl::range<3> _range;
    };
    template <class T, memory_region Memory> class accessor<T, Memory, 2> {
    public:
        using memory_t = detail::memory_traits<Memory, T>;
        using element_t = typename memory_t::element_t;
        using pointer_t = typename memory_t::pointer_t;
        using accessor_t = typename memory_t::template accessor_t<2>;
        accessor(pointer_t data, const sycl::range<2> &in_range)
            : _data(data), _range(in_range) {}
        template <memory_region M = Memory>
        accessor(typename std::enable_if<M != local, const accessor_t>::type &acc)
            : accessor(acc, acc.get_range()) {}
        accessor(const accessor_t &acc, const sycl::range<2> &in_range)
            : accessor(acc.get_pointer(), in_range) {}

        pointer_t operator[](size_t index) const {
            return _data + _range.get(1) * index;
        }

        pointer_t get_ptr() const { return _data; }

    private:
        pointer_t _data;
        sycl::range<2> _range;
    };

    namespace detail {
        /// Device variable with address space of shared, global or constant.
        template <class T, memory_region Memory, size_t Dimension> class device_memory {
        public:
            using accessor_t =
                typename detail::memory_traits<Memory,
                                            T>::template accessor_t<Dimension>;
            using value_t = typename detail::memory_traits<Memory, T>::value_t;
            using dpct_accessor_t = dpct::accessor<T, Memory, Dimension>;

            device_memory() : device_memory(sycl::range<Dimension>(1)) {}

            /// Constructor of 1-D array with initializer list
            device_memory(const sycl::range<Dimension> &in_range,
                        std::initializer_list<value_t> &&init_list)
                : device_memory(in_range) {
                assert(init_list.size() <= in_range.size());
                _host_ptr = (value_t *)std::malloc(_size);
                std::memset(_host_ptr, 0, _size);
                std::memcpy(_host_ptr, init_list.begin(), init_list.size() * sizeof(T));
            }

            /// Constructor of 2-D array with initializer list
            template <size_t D = Dimension>
            device_memory(
                const typename std::enable_if<D == 2, sycl::range<2>>::type &in_range,
                std::initializer_list<std::initializer_list<value_t>> &&init_list)
                : device_memory(in_range) {
                assert(init_list.size() <= in_range[0]);
                _host_ptr = (value_t *)std::malloc(_size);
                std::memset(_host_ptr, 0, _size);
                auto tmp_data = _host_ptr;
                for (auto sub_list : init_list) {
                    assert(sub_list.size() <= in_range[1]);
                    std::memcpy(tmp_data, sub_list.begin(),
                                sub_list.size() * sizeof(T));
                    tmp_data += in_range[1];
                }
            }

            /// Constructor with range
            device_memory(const sycl::range<Dimension> &range_in)
                : _size(range_in.size() * sizeof(T)), _range(range_in),
                _reference(false), _host_ptr(nullptr), _device_ptr(nullptr) {
                static_assert(
                    (Memory == global) || (Memory == constant) || (Memory == shared),
                    "device memory region should be global, constant or shared");
                // Make sure that singleton class mem_mgr and dev_mgr will destruct
                // later than this.
                detail::mem_mgr::instance();
                dev_mgr::instance();
            }

            /// Constructor with range
            template <class... Args>
            device_memory(Args... Arguments)
                : device_memory(sycl::range<Dimension>(Arguments...)) {}

            ~device_memory() {
                if (_device_ptr && !_reference)
                    dpct::dpct_free(_device_ptr);
                if (_host_ptr)
                    std::free(_host_ptr);
            }

            /// Allocate memory with default queue, and init memory if has initial
            /// value.
            void init() { init(dpct::get_default_queue()); }
            /// Allocate memory with specified queue, and init memory if has initial
            /// value.
            void init(sycl::queue &q) {
                if (_device_ptr)
                    return;
                if (!_size)
                    return;
                allocate_device(q);
                if (_host_ptr)
                    detail::dpct_memcpy(q, _device_ptr, _host_ptr, _size,
                                        host_to_device);
            }

            /// The variable is assigned to a device pointer.
            void assign(value_t *src, size_t size) {
                this->~device_memory();
                new (this) device_memory(src, size);
            }

            /// Get memory pointer of the memory object, which is virtual pointer when
            /// usm is not used, and device pointer when usm is used.
            value_t *get_ptr() { return get_ptr(get_default_queue()); }
            /// Get memory pointer of the memory object, which is virtual pointer when
            /// usm is not used, and device pointer when usm is used.
            value_t *get_ptr(sycl::queue &q) {
                init(q);
                return _device_ptr;
            }

            /// Get the device memory object size in bytes.
            size_t get_size() { return _size; }

            template <size_t D = Dimension>
            typename std::enable_if<D == 1, T>::type &operator[](size_t index) {
                init();
                return _device_ptr[index];
            }

            /// Get dpct::accessor with dimension info for the device memory object
            /// when usm is used and dimension is greater than 1.
            template <size_t D = Dimension>
            typename std::enable_if<D != 1, dpct_accessor_t>::type
            get_access([[maybe_unused]] sycl::handler &cgh) {
                return dpct_accessor_t((T *)_device_ptr, _range);
            }

        private:
            device_memory(value_t *memory_ptr, size_t size)
                : _size(size), _range(size / sizeof(T)), _reference(true),
                _device_ptr(memory_ptr) {}

            void allocate_device(sycl::queue &q) {
        #ifndef DPCT_USM_LEVEL_NONE
                if (Memory == shared) {
                    _device_ptr = (value_t *)sycl::malloc_shared(_size, q.get_device(),
                                                                q.get_context());
                    return;
                }
        #ifdef SYCL_EXT_ONEAPI_USM_DEVICE_READ_ONLY
                if (Memory == constant) {
                    _device_ptr = (value_t *)sycl::malloc_device(
                        _size, q.get_device(), q.get_context(),
                        sycl::ext::oneapi::property::usm::device_read_only());
                    return;
                }
        #endif
        #endif
                _device_ptr = (value_t *)detail::dpct_malloc(_size, q);
            }

            size_t _size;
            sycl::range<Dimension> _range;
            bool _reference;
            value_t *_host_ptr;
            value_t *_device_ptr;
        };
        template <class T, memory_region Memory>
        class device_memory<T, Memory, 0> : public device_memory<T, Memory, 1> {
        public:
            using base = device_memory<T, Memory, 1>;
            using value_t = typename base::value_t;
            using accessor_t =
                typename detail::memory_traits<Memory, T>::template accessor_t<0>;

            /// Constructor with initial value.
            device_memory(const value_t &val) : base(sycl::range<1>(1), {val}) {}

            /// Default constructor
            device_memory() : base(1) {}
        };
        } // namespace detail

    template <class T, size_t Dimension>
    using global_memory = detail::device_memory<T, global, Dimension>;
    template <class T, size_t Dimension>
    using constant_memory = detail::device_memory<T, constant, Dimension>;
    template <class T, size_t Dimension>
    using shared_memory = detail::device_memory<T, shared, Dimension>;


    template <typename T,
            sycl::access::address_space addressSpace =
                sycl::access::address_space::global_space,
            sycl::memory_order memoryOrder = sycl::memory_order::relaxed,
            sycl::memory_scope memoryScope = sycl::memory_scope::device>
    inline T atomic_fetch_add(T *addr, T operand) {
    auto atm =
        sycl::atomic_ref<T, memoryOrder, memoryScope, addressSpace>(addr[0]);
    return atm.fetch_add(operand);
    }

    template <sycl::access::address_space addressSpace =
                sycl::access::address_space::global_space,
            sycl::memory_order memoryOrder = sycl::memory_order::relaxed,
            sycl::memory_scope memoryScope = sycl::memory_scope::device,
            typename T1, typename T2>
    inline T1 atomic_fetch_add(T1 *addr, T2 operand) {
    auto atm =
        sycl::atomic_ref<T1, memoryOrder, memoryScope, addressSpace>(addr[0]);
    return atm.fetch_add(operand);
    }

    template <typename T, sycl::access::address_space addressSpace =
                            sycl::access::address_space::global_space>
    inline T atomic_fetch_add(T *addr, T operand,
                            sycl::memory_order memoryOrder) {
    switch (memoryOrder) {
        case sycl::memory_order::relaxed:
            return atomic_fetch_add<T, addressSpace, sycl::memory_order::relaxed,
                                    sycl::memory_scope::device>(addr, operand);
        case sycl::memory_order::acq_rel:
            return atomic_fetch_add<T, addressSpace, sycl::memory_order::acq_rel,
                                    sycl::memory_scope::device>(addr, operand);
        case sycl::memory_order::seq_cst:
            return atomic_fetch_add<T, addressSpace, sycl::memory_order::seq_cst,
                                    sycl::memory_scope::device>(addr, operand);
        default:
            assert(false && "Invalid memory_order for atomics. Valid memory_order for "
                            "atomics are: sycl::memory_order::relaxed, "
                            "sycl::memory_order::acq_rel, sycl::memory_order::seq_cst!");
        }
    }

    template <sycl::access::address_space addressSpace =
                sycl::access::address_space::global_space,
            typename T1, typename T2>
    inline T1 atomic_fetch_add(T1 *addr, T2 operand,
                            sycl::memory_order memoryOrder) {
    atomic_fetch_add<T1, addressSpace>(addr, operand, memoryOrder);
    }

} // COPY from DPCT head files

#endif // GGML_SYCL_DPCT_HELPER_HPP