common.hpp

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#pragma once
 
#include <algorithm>
#include <cstddef>
#include <cstdint>
#include <utility>
#include <vector>
 
#include <sycl/sycl.hpp>
 
// dpctl tensor headers
#include "kernels/alignment.hpp"
#include "kernels/elementwise_functions/common.hpp"
#include "utils/sycl_utils.hpp"
 
namespace dpnp::extensions::py_internal::elementwise_common
{
using dpctl::tensor::kernels::alignment_utils::
    disabled_sg_loadstore_wrapper_krn;
using dpctl::tensor::kernels::alignment_utils::is_aligned;
using dpctl::tensor::kernels::alignment_utils::required_alignment;
 
using dpctl::tensor::kernels::elementwise_common::select_lws;
 
using dpctl::tensor::sycl_utils::sub_group_load;
using dpctl::tensor::sycl_utils::sub_group_store;
 
template <typename argT,
          typename resT1,
          typename resT2,
          typename UnaryTwoOutputsOpT,
          std::uint8_t vec_sz = 4u,
          std::uint8_t n_vecs = 2u,
          bool enable_sg_loadstore = true>
struct UnaryTwoOutputsContigFunctor
{
private:
    const argT *in = nullptr;
    resT1 *out1 = nullptr;
    resT2 *out2 = nullptr;
    std::size_t nelems_;
 
public:
    UnaryTwoOutputsContigFunctor(const argT *inp,
                                 resT1 *res1,
                                 resT2 *res2,
                                 const std::size_t n_elems)
        : in(inp), out1(res1), out2(res2), nelems_(n_elems)
    {
    }
 
    void operator()(sycl::nd_item<1> ndit) const
    {
        static constexpr std::uint8_t elems_per_wi = n_vecs * vec_sz;
        UnaryTwoOutputsOpT op{};
        /* Each work-item processes vec_sz elements, contiguous in memory */
        /* NOTE: work-group size must be divisible by sub-group size */
 
        if constexpr (enable_sg_loadstore &&
                      UnaryTwoOutputsOpT::is_constant::value) {
            // value of operator is known to be a known constant
            constexpr resT1 const_val1 = UnaryTwoOutputsOpT::constant_value1;
            constexpr resT2 const_val2 = UnaryTwoOutputsOpT::constant_value2;
 
            auto sg = ndit.get_sub_group();
            const std::uint16_t sgSize = sg.get_max_local_range()[0];
 
            const std::size_t base =
                elems_per_wi * (ndit.get_group(0) * ndit.get_local_range(0) +
                                sg.get_group_id()[0] * sgSize);
            if (base + elems_per_wi * sgSize < nelems_) {
                static constexpr sycl::vec<resT1, vec_sz> res1_vec(const_val1);
                static constexpr sycl::vec<resT2, vec_sz> res2_vec(const_val2);
#pragma unroll
                for (std::uint8_t it = 0; it < elems_per_wi; it += vec_sz) {
                    const std::size_t offset = base + it * sgSize;
                    auto out1_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&out1[offset]);
                    auto out2_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&out2[offset]);
 
                    sub_group_store<vec_sz>(sg, res1_vec, out1_multi_ptr);
                    sub_group_store<vec_sz>(sg, res2_vec, out2_multi_ptr);
                }
            }
            else {
                const std::size_t lane_id = sg.get_local_id()[0];
                for (std::size_t k = base + lane_id; k < nelems_; k += sgSize) {
                    out1[k] = const_val1;
                    out2[k] = const_val2;
                }
            }
        }
        else if constexpr (enable_sg_loadstore &&
                           UnaryTwoOutputsOpT::supports_sg_loadstore::value &&
                           UnaryTwoOutputsOpT::supports_vec::value &&
                           (vec_sz > 1))
        {
            auto sg = ndit.get_sub_group();
            const std::uint16_t sgSize = sg.get_max_local_range()[0];
 
            const std::size_t base =
                elems_per_wi * (ndit.get_group(0) * ndit.get_local_range(0) +
                                sg.get_group_id()[0] * sgSize);
            if (base + elems_per_wi * sgSize < nelems_) {
#pragma unroll
                for (std::uint8_t it = 0; it < elems_per_wi; it += vec_sz) {
                    const std::size_t offset = base + it * sgSize;
                    auto in_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&in[offset]);
                    auto out1_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&out1[offset]);
                    auto out2_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&out2[offset]);
 
                    const sycl::vec<argT, vec_sz> x =
                        sub_group_load<vec_sz>(sg, in_multi_ptr);
                    sycl::vec<resT2, vec_sz> res2_vec = {};
                    const sycl::vec<resT1, vec_sz> res1_vec = op(x, res2_vec);
                    sub_group_store<vec_sz>(sg, res1_vec, out1_multi_ptr);
                    sub_group_store<vec_sz>(sg, res2_vec, out2_multi_ptr);
                }
            }
            else {
                const std::size_t lane_id = sg.get_local_id()[0];
                for (std::size_t k = base + lane_id; k < nelems_; k += sgSize) {
                    // scalar call
                    out1[k] = op(in[k], out2[k]);
                }
            }
        }
        else if constexpr (enable_sg_loadstore &&
                           UnaryTwoOutputsOpT::supports_sg_loadstore::value &&
                           std::is_same_v<resT1, argT>)
        {
            // default: use scalar-value function
 
            auto sg = ndit.get_sub_group();
            const std::uint16_t sgSize = sg.get_max_local_range()[0];
            const std::size_t base =
                elems_per_wi * (ndit.get_group(0) * ndit.get_local_range(0) +
                                sg.get_group_id()[0] * sgSize);
 
            if (base + elems_per_wi * sgSize < nelems_) {
#pragma unroll
                for (std::uint8_t it = 0; it < elems_per_wi; it += vec_sz) {
                    const std::size_t offset = base + it * sgSize;
                    auto in_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&in[offset]);
                    auto out1_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&out1[offset]);
                    auto out2_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&out2[offset]);
 
                    sycl::vec<argT, vec_sz> arg_vec =
                        sub_group_load<vec_sz>(sg, in_multi_ptr);
                    sycl::vec<resT2, vec_sz> res2_vec = {};
#pragma unroll
                    for (std::uint32_t k = 0; k < vec_sz; ++k) {
                        arg_vec[k] = op(arg_vec[k], res2_vec[k]);
                    }
                    sub_group_store<vec_sz>(sg, arg_vec, out1_multi_ptr);
                    sub_group_store<vec_sz>(sg, res2_vec, out2_multi_ptr);
                }
            }
            else {
                const std::size_t lane_id = sg.get_local_id()[0];
                for (std::size_t k = base + lane_id; k < nelems_; k += sgSize) {
                    out1[k] = op(in[k], out2[k]);
                }
            }
        }
        else if constexpr (enable_sg_loadstore &&
                           UnaryTwoOutputsOpT::supports_sg_loadstore::value)
        {
            // default: use scalar-value function
 
            auto sg = ndit.get_sub_group();
            const std::uint16_t sgSize = sg.get_max_local_range()[0];
            const std::size_t base =
                elems_per_wi * (ndit.get_group(0) * ndit.get_local_range(0) +
                                sg.get_group_id()[0] * sgSize);
 
            if (base + elems_per_wi * sgSize < nelems_) {
#pragma unroll
                for (std::uint8_t it = 0; it < elems_per_wi; it += vec_sz) {
                    const std::size_t offset = base + it * sgSize;
                    auto in_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&in[offset]);
                    auto out1_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&out1[offset]);
                    auto out2_multi_ptr = sycl::address_space_cast<
                        sycl::access::address_space::global_space,
                        sycl::access::decorated::yes>(&out2[offset]);
 
                    const sycl::vec<argT, vec_sz> arg_vec =
                        sub_group_load<vec_sz>(sg, in_multi_ptr);
                    sycl::vec<resT1, vec_sz> res1_vec = {};
                    sycl::vec<resT2, vec_sz> res2_vec = {};
#pragma unroll
                    for (std::uint8_t k = 0; k < vec_sz; ++k) {
                        res1_vec[k] = op(arg_vec[k], res2_vec[k]);
                    }
                    sub_group_store<vec_sz>(sg, res1_vec, out1_multi_ptr);
                    sub_group_store<vec_sz>(sg, res2_vec, out2_multi_ptr);
                }
            }
            else {
                const std::size_t lane_id = sg.get_local_id()[0];
                for (std::size_t k = base + lane_id; k < nelems_; k += sgSize) {
                    out1[k] = op(in[k], out2[k]);
                }
            }
        }
        else {
            const std::uint16_t sgSize =
                ndit.get_sub_group().get_local_range()[0];
            const std::size_t gid = ndit.get_global_linear_id();
            const std::uint16_t elems_per_sg = sgSize * elems_per_wi;
 
            const std::size_t start =
                (gid / sgSize) * (elems_per_sg - sgSize) + gid;
            const std::size_t end = std::min(nelems_, start + elems_per_sg);
            for (std::size_t offset = start; offset < end; offset += sgSize) {
                out1[offset] = op(in[offset], out2[offset]);
            }
        }
    }
};
 
template <typename argT,
          typename resT1,
          typename resT2,
          typename IndexerT,
          typename UnaryTwoOutputsOpT>
struct UnaryTwoOutputsStridedFunctor
{
private:
    const argT *inp_ = nullptr;
    resT1 *res1_ = nullptr;
    resT2 *res2_ = nullptr;
    IndexerT inp_out_indexer_;
 
public:
    UnaryTwoOutputsStridedFunctor(const argT *inp_p,
                                  resT1 *res1_p,
                                  resT2 *res2_p,
                                  const IndexerT &inp_out_indexer)
        : inp_(inp_p), res1_(res1_p), res2_(res2_p),
          inp_out_indexer_(inp_out_indexer)
    {
    }
 
    void operator()(sycl::id<1> wid) const
    {
        const auto &offsets_ = inp_out_indexer_(wid.get(0));
        const ssize_t &inp_offset = offsets_.get_first_offset();
        const ssize_t &res1_offset = offsets_.get_second_offset();
        const ssize_t &res2_offset = offsets_.get_third_offset();
 
        UnaryTwoOutputsOpT op{};
 
        res1_[res1_offset] = op(inp_[inp_offset], res2_[res2_offset]);
    }
};
 
template <typename argTy,
          template <typename T>
          class UnaryTwoOutputsType,
          template <typename A,
                    typename R1,
                    typename R2,
                    std::uint8_t vs,
                    std::uint8_t nv,
                    bool enable>
          class UnaryTwoOutputsContigFunctorT,
          template <typename A,
                    typename R1,
                    typename R2,
                    std::uint8_t vs,
                    std::uint8_t nv>
          class kernel_name,
          std::uint8_t vec_sz = 4u,
          std::uint8_t n_vecs = 2u>
sycl::event
    unary_two_outputs_contig_impl(sycl::queue &exec_q,
                                  std::size_t nelems,
                                  const char *arg_p,
                                  char *res1_p,
                                  char *res2_p,
                                  const std::vector<sycl::event> &depends = {})
{
    static constexpr std::uint8_t elems_per_wi = n_vecs * vec_sz;
    const std::size_t n_work_items_needed = nelems / elems_per_wi;
    const std::size_t lws =
        select_lws(exec_q.get_device(), n_work_items_needed);
 
    const std::size_t n_groups =
        ((nelems + lws * elems_per_wi - 1) / (lws * elems_per_wi));
    const auto gws_range = sycl::range<1>(n_groups * lws);
    const auto lws_range = sycl::range<1>(lws);
 
    using resTy1 = typename UnaryTwoOutputsType<argTy>::value_type1;
    using resTy2 = typename UnaryTwoOutputsType<argTy>::value_type2;
    using BaseKernelName = kernel_name<argTy, resTy1, resTy2, vec_sz, n_vecs>;
 
    const argTy *arg_tp = reinterpret_cast<const argTy *>(arg_p);
    resTy1 *res1_tp = reinterpret_cast<resTy1 *>(res1_p);
    resTy2 *res2_tp = reinterpret_cast<resTy2 *>(res2_p);
 
    sycl::event comp_ev = exec_q.submit([&](sycl::handler &cgh) {
        cgh.depends_on(depends);
 
        if (is_aligned<required_alignment>(arg_p) &&
            is_aligned<required_alignment>(res1_p) &&
            is_aligned<required_alignment>(res2_p))
        {
            static constexpr bool enable_sg_loadstore = true;
            using KernelName = BaseKernelName;
            using Impl =
                UnaryTwoOutputsContigFunctorT<argTy, resTy1, resTy2, vec_sz,
                                              n_vecs, enable_sg_loadstore>;
 
            cgh.parallel_for<KernelName>(
                sycl::nd_range<1>(gws_range, lws_range),
                Impl(arg_tp, res1_tp, res2_tp, nelems));
        }
        else {
            static constexpr bool disable_sg_loadstore = false;
            using KernelName =
                disabled_sg_loadstore_wrapper_krn<BaseKernelName>;
            using Impl =
                UnaryTwoOutputsContigFunctorT<argTy, resTy1, resTy2, vec_sz,
                                              n_vecs, disable_sg_loadstore>;
 
            cgh.parallel_for<KernelName>(
                sycl::nd_range<1>(gws_range, lws_range),
                Impl(arg_tp, res1_tp, res2_tp, nelems));
        }
    });
 
    return comp_ev;
}
 
template <typename argTy,
          template <typename T>
          class UnaryTwoOutputsType,
          template <typename A, typename R1, typename R2, typename I>
          class UnaryTwoOutputsStridedFunctorT,
          template <typename A, typename R1, typename R2, typename I>
          class kernel_name>
sycl::event unary_two_outputs_strided_impl(
    sycl::queue &exec_q,
    std::size_t nelems,
    int nd,
    const ssize_t *shape_and_strides,
    const char *arg_p,
    ssize_t arg_offset,
    char *res1_p,
    ssize_t res1_offset,
    char *res2_p,
    ssize_t res2_offset,
    const std::vector<sycl::event> &depends,
    const std::vector<sycl::event> &additional_depends)
{
    sycl::event comp_ev = exec_q.submit([&](sycl::handler &cgh) {
        cgh.depends_on(depends);
        cgh.depends_on(additional_depends);
 
        using res1Ty = typename UnaryTwoOutputsType<argTy>::value_type1;
        using res2Ty = typename UnaryTwoOutputsType<argTy>::value_type2;
        using IndexerT =
            typename dpctl::tensor::offset_utils::ThreeOffsets_StridedIndexer;
 
        const IndexerT indexer{nd, arg_offset, res1_offset, res2_offset,
                               shape_and_strides};
 
        const argTy *arg_tp = reinterpret_cast<const argTy *>(arg_p);
        res1Ty *res1_tp = reinterpret_cast<res1Ty *>(res1_p);
        res2Ty *res2_tp = reinterpret_cast<res2Ty *>(res2_p);
 
        using Impl =
            UnaryTwoOutputsStridedFunctorT<argTy, res1Ty, res2Ty, IndexerT>;
 
        cgh.parallel_for<kernel_name<argTy, res1Ty, res2Ty, IndexerT>>(
            {nelems}, Impl(arg_tp, res1_tp, res2_tp, indexer));
    });
    return comp_ev;
}
 
// Typedefs for function pointers
 
typedef sycl::event (*unary_two_outputs_contig_impl_fn_ptr_t)(
    sycl::queue &,
    std::size_t,
    const char *,
    char *,
    char *,
    const std::vector<sycl::event> &);
 
typedef sycl::event (*unary_two_outputs_strided_impl_fn_ptr_t)(
    sycl::queue &,
    std::size_t,
    int,
    const ssize_t *,
    const char *,
    ssize_t,
    char *,
    ssize_t,
    char *,
    ssize_t,
    const std::vector<sycl::event> &,
    const std::vector<sycl::event> &);
 
} // namespace dpnp::extensions::py_internal::elementwise_common