/*******************************************************************************
* Copyright 2021 Intel Corporation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*******************************************************************************/

#ifndef CPU_X64_BRGEMM_JIT_BRDGMM_KERNEL_HPP
#define CPU_X64_BRGEMM_JIT_BRDGMM_KERNEL_HPP

#include "common/c_types_map.hpp"
#include "common/nstl.hpp"
#include "common/type_helpers.hpp"
#include "common/utils.hpp"

#include "cpu/x64/brgemm/brgemm_types.hpp"
#include "cpu/x64/cpu_barrier.hpp"
#include "cpu/x64/injectors/jit_uni_postops_injector.hpp"
#include "cpu/x64/jit_avx512_core_bf16cvt.hpp"
#include "cpu/x64/jit_generator.hpp"

namespace dnnl {
namespace impl {
namespace cpu {
namespace x64 {

template <typename Wmm>
struct jit_brdgmm_kernel_base_t : public jit_base_brgemm_kernel_t {
    jit_brdgmm_kernel_base_t(const brgemm_desc_t &abrd);

    DECLARE_CPU_JIT_AUX_FUNCTIONS(jit_brdgmm_kernel_base_t)

    brgemm_desc_t brg;

    static bool is_fast_vnni_int8(const brgemm_desc_t &brg) {
        return brg.is_dgmm && brg.is_int8 && brg.isa_impl == avx512_core_vnni
                && brg.ldb_tail /*n_vlen_tail*/ == 0;
    }

    struct vmm_allocator_helper_t {
        vmm_allocator_helper_t(const brgemm_desc_t &brg)
            : aux_vmm_count_(0)
            , vmm_tmp_count_(0)
            , compute_vmm_base_idx_(-1)
            , compute_vmm_count_((grouped_bs(brg) ? 0 : 1)
                      + (!is_fma_embd(brg))
                              * brg.ld_block2 /*n_block*/) // vmm_a + vmm_b
            , idx_vmm_a_(-1)
            , idx_vmm_b_(-1)
            , idx_vmm_permute_(-1)
            , idx_vmm_shift_(-1)
            , idx_vmm_zp_comp_(-1)
            , idx_vmm_bcast_(-1)
            , idx_vmm_s8s8_comp_(-1) {

            if (brg.with_sum || brg.with_wei_scales) vmm_tmp_count_ = 2;

            // assign aux vmms
            if (is_fast_vnni_int8(brg)) idx_vmm_permute_ = aux_vmm_count_++;
            if (brg.req_s8s8_compensation) {
                idx_vmm_shift_ = aux_vmm_count_;
                idx_vmm_s8s8_comp_ = aux_vmm_count_++;
                assert(idx_vmm_shift_ == idx_vmm_s8s8_comp_);
            }
            const bool compute_src_zp
                    = brg.zp_type_a != brgemm_broadcast_t::none;
            if (compute_src_zp) {
                idx_vmm_zp_comp_ = aux_vmm_count_++;
                if (!is_superset(brg.isa_impl, avx512_core))
                    idx_vmm_bcast_ = aux_vmm_count_++;
            } else if (brg.with_sum
                    && (!is_superset(brg.isa_impl, avx512_core))) {
                const bool p_sum_scale_reg_set = brg.sum_scale != 1.f;
                if (p_sum_scale_reg_set)
                    idx_vmm_bcast_
                            = aux_vmm_count_++; // need extra vmm for broadcast
            }
            compute_vmm_base_idx_ = aux_vmm_count_;

            // assign compute vmms
            idx_vmm_a_ = compute_vmm_base_idx_;
            const int max_m = brg.bd_block2 + brg.bs_group - 1;
            const int max_n = brg.ld_block2;
            idx_vmm_b_
                    = vmm_a_idx(brg, max_m - 1, max_n - 1) + !is_fma_embd(brg);
        }
        int vnni_substep(const brgemm_desc_t &brg) const {
            return brg.isa_impl == avx2_vnni_2 && brg.is_xf16() ? 2 : 1;
        }
        int vmm_a_idx(const brgemm_desc_t &brg, int m, int n) const {
            const auto idx_offset = grouped_bs(brg)
                    ? (m * brg.ld_block2 + n) * vnni_substep(brg)
                    : 0;
            return idx_vmm_a_ + idx_offset;
        }

        int get_compute_vmm_count() { return compute_vmm_count_; }
        int get_aux_vmm_count() {
            return nstl::max(vmm_tmp_count_, aux_vmm_count_);
        }
        int get_idx_vmm_a() {
            assert(idx_vmm_a_ >= 0);
            return idx_vmm_a_;
        }
        int get_idx_vmm_b() {
            assert(idx_vmm_b_ >= 0);
            return idx_vmm_b_;
        }
        int get_idx_vmm_permute() {
            assert(idx_vmm_permute_ >= 0);
            return idx_vmm_permute_;
        }
        int get_idx_vmm_shift() {
            assert(idx_vmm_shift_ >= 0);
            return idx_vmm_shift_;
        }
        int get_idx_vmm_zp_comp() {
            assert(idx_vmm_zp_comp_ >= 0);
            return idx_vmm_zp_comp_;
        }
        int get_idx_vmm_bcast() {
            assert(idx_vmm_bcast_ >= 0);
            return idx_vmm_bcast_;
        }
        int get_idx_vmm_s8s8_comp() {
            assert(idx_vmm_s8s8_comp_ >= 0);
            return idx_vmm_s8s8_comp_;
        }

    private:
        int aux_vmm_count_;
        int vmm_tmp_count_;
        int compute_vmm_base_idx_;
        int compute_vmm_count_;
        int idx_vmm_a_;
        int idx_vmm_b_;
        int idx_vmm_permute_;
        int idx_vmm_shift_;
        int idx_vmm_zp_comp_;
        int idx_vmm_bcast_;
        int idx_vmm_s8s8_comp_;
    };

    static int get_aux_vmm_count(const brgemm_desc_t &brg) {
        auto vmm_alloc = vmm_allocator_helper_t(brg);
        return vmm_alloc.get_aux_vmm_count();
    }

    static int get_compute_vmm_count(const brgemm_desc_t &brg) {
        auto vmm_alloc = vmm_allocator_helper_t(brg);
        return vmm_alloc.get_compute_vmm_count();
    }

    const brgemm_desc_t &get_brg() const override { return brg; }

private:
    // note: this kernel doesn't yet support TMM's. We differentiate Wmm and Vmm
    // just to follow same template style as brgemm_kernel.
    using Vmm =
            typename utils::conditional<std::is_same<Wmm, Xbyak::Tmm>::value,
                    Xbyak::Zmm, Wmm>::type;
    using Vmm_low_t = typename vreg_traits_t<Vmm>::Vmm_lower_t;
    using po_injector_t = injector::jit_uni_postops_injector_base_t<Vmm>;
    std::unique_ptr<po_injector_t> postops_injector_;
    std::unique_ptr<bf16_emulation_t> bf16_emu_;

    Xbyak::Label permute_index_table;

    enum class compute_pad_kernel_t { s8s8_kernel, zero_point_kernel };

    injector_utils::registry_scratchpad_t regscratchpad_ {*this, brg.isa_impl};

    using reg64_t = const Xbyak::Reg64;
    // Register decomposition
    const reg64_t param1 = abi_param1;
    const reg64_t reg_A = abi_not_param1;
    const reg64_t reg_B = r8;
    // reg_aux_batch_addr changed in advance_A_B_matrices,
    // so need to be savable
    const injector_utils::reg64_savable_t reg_aux_batch_addr {
            regscratchpad_, r15};
    const reg64_t reg_BS = rsi;

    // loop variables
    const reg64_t reg_BS_loop = r12;
    const reg64_t reg_aux_M = r13;
    const reg64_t reg_aux_D = rbx;
    const injector_utils::reg64_savable_t reg_aux_C {
            regscratchpad_, rdx, rdx, may_use_rbp()};
    const reg64_t reg_aux_A = r10;
    const reg64_t reg_aux_B = abi_param1;
    const injector_utils::reg64_savable_t reg_aux1_A {
            regscratchpad_, abi_not_param1}; // brgemm_strd
    const injector_utils::reg64_savable_t reg_aux1_B {
            regscratchpad_, r8}; // brgemm_strd
    const reg64_t reg_a_offset = r9;
    const reg64_t reg_aux_N = r11;

    const reg64_t reg_aux_A_vpad_top = r14;
    const injector_utils::reg64_savable_t reg_aux_A_vpad_bottom {
            regscratchpad_, rdx, rbp, may_use_rbp()};

    const reg64_t reg_table_base = rax;
    const reg64_t reg_tmp = reg_table_base;
    const reg64_t reg_total_padding = reg_table_base;
    // reg_aux_bias changed in store_accumulators_apply_post_ops
    const injector_utils::reg64_savable_t reg_aux_bias {regscratchpad_, rax};
    const injector_utils::reg64_savable_t reg_aux_src_scales {
            regscratchpad_, rax};
    // reg_aux_wei_scales changed in store_accumulators_apply_post_ops,
    // so need to be savable
    const injector_utils::reg64_savable_t reg_aux_wei_scales {
            regscratchpad_, rax};
    const injector_utils::reg64_savable_t reg_aux_dst_scales {
            regscratchpad_, rax, r22};
    const injector_utils::reg64_savable_t reg_dst_zero_point {
            regscratchpad_, rax, r23};
    const injector_utils::reg64_savable_t reg_src_zero_point {
            regscratchpad_, rax, r24};
    const injector_utils::reg64_savable_t reg_zp_compensation {
            regscratchpad_, r12, r25};
    // abi_param1 is used in post-ops injector and by reg_aux_B,
    // so need to be savable or use other registers
    const injector_utils::reg64_savable_t reg_binary_params {
            regscratchpad_, abi_param1};
    const injector_utils::reg64_savable_t reg_ptr_sum_scale {
            regscratchpad_, r14, r27};
    const injector_utils::reg64_savable_t reg_ptr_sum_zp {
            regscratchpad_, rax, r28};
    const injector_utils::reg64_savable_t reg_s8s8_comp {
            regscratchpad_, r14, r29};

    Xbyak::Opmask k_mask = Xbyak::Opmask(2);
    Xbyak::Opmask k_tail_mask = Xbyak::Opmask(3);
    Xbyak::Opmask kblend_mask = Xbyak::Opmask(4);

    /* used for bfloat16 */
    reg64_t bf16_emu_scratch = reg_table_base;
    Xbyak::Zmm bf16_emu_reserv_1 = Xbyak::Zmm(0);
    Xbyak::Zmm bf16_emu_reserv_2 = Xbyak::Zmm(1);
    Xbyak::Zmm bf16_emu_reserv_3 = Xbyak::Zmm(2);
    Xbyak::Zmm bf16_emu_reserv_4 = Xbyak::Zmm(3);
    // note 1: zmm reserv_5 is not necessary since it's only used for
    // 'vdpbf16ps'
    // note 2: zmm0 collides with vmm_permute, hence need to write this value
    // before every loop.

    const int simd_w_;
    const int max_vmms_;
    const bool compute_dst_zp_, compute_src_zp_;
    const bool is_src_zp_bcast_;
    const bool compute_compensation_; // code-path for either s8s8 or src_zp
    const bool has_vpad_; // vertical padding w.r.t. M dimension
    const bool has_bpad_; // batch pad is computed for the overlap between the
            // weights and input height padding

    vmm_allocator_helper_t vmm_alloc;

    bool with_binary_non_scalar_bcast_ = false;

    inline int M() { return brg.bcast_dim; }
    inline int N() { return brg.load_dim; }
    inline int m_block2() { return brg.bd_block2; }
    inline int nb_m_block2() { return brg.bdb2; }
    inline int m_block2_tail() { return brg.bdb2_tail; }

    inline int n_block1() { return brg.ld_block; }
    inline int nb_n_block1() { return brg.ldb; }
    inline int n_block1_tail() { return brg.ldb_tail; }
    inline int n_block2() { return brg.ld_block2; }
    inline int nb_n_block2() { return brg.ldb2; }
    inline int n_block2_tail() { return brg.ldb2_tail; }
    int tail_length() { return n_block1_tail() % simd_w_; }

    inline int bs_group() const { return brg.bs_group; }
    static bool grouped_bs(const brgemm_desc_t &brg) {
        return brg.bs_group > 1;
    }
    inline bool grouped_bs() const { return grouped_bs(brg); }
    static bool is_fma_embd(const brgemm_desc_t &brg) {
        return grouped_bs(brg)
                ? false
                : brg.is_f32 && is_superset(brg.isa_impl, avx512_core);
    }
    bool is_fma_embd() { return is_fma_embd(brg); }
    bool is_fast_vnni_int8() { return is_fast_vnni_int8(brg); }
    bool is_slow_bf16_vnni() {
        // On avx512_core_amx machines, the bf16 vnni is found to be slower.
        // TODO: Check the above limitations on new cpus
        return brg.is_bf16 && mayiuse(avx512_core_amx);
    }

    bool req_vmm_reload() { return brg.is_bf16_emu; }
    bool assign_data_vmm_once() { return !req_vmm_reload(); }

    int vnni_substep() { return vmm_alloc.vnni_substep(brg); }

    int get_substep_simd(int n_i, int v_i, bool has_n_tail) {
        const int last_n_block_sz
                = n_block2_tail() > 0 ? n_block2_tail() : n_block2();
        if (has_n_tail && n_i + 1 == last_n_block_sz) {
            return nstl::min(simd_w_, n_block1_tail() - v_i * simd_w_);
        } else {
            return simd_w_;
        }
    }
    Vmm vmm_a(int m, int n) {
        const auto idx_a = vmm_alloc.vmm_a_idx(brg, m, n);
        assert(idx_a < (vmm_alloc.get_idx_vmm_b() + is_fma_embd()));
        return Vmm(idx_a);
    }
    Vmm vmm_b(int bi = 0) { return Vmm(vmm_alloc.get_idx_vmm_b() + bi); }
    Vmm accm(int m_blocks, int n_blocks, int m, int n, int vnni_idx) {
        assert(m_blocks <= m_block2() && m < m_blocks);
        assert(n_blocks <= n_block2() && n < n_blocks);
        const int accm_start = max_vmms_ - m_blocks * n_blocks * vnni_substep();
        const int accm_rel_idx
                = m * n_blocks * vnni_substep() + n * vnni_substep() + vnni_idx;
        const int idx = accm_start + accm_rel_idx;
        assert(idx < max_vmms_ && idx > vmm_b(0).getIdx());
        return Vmm(idx);
    }
    Vmm vmm_permute() { return Vmm(vmm_alloc.get_idx_vmm_permute()); }
    Vmm vmm_shift() { // -128's
        return Vmm(vmm_alloc.get_idx_vmm_shift());
    }
    Vmm vmm_s8s8_comp() { return Vmm(vmm_alloc.get_idx_vmm_s8s8_comp()); }
    Vmm vmm_zp_comp() { return Vmm(vmm_alloc.get_idx_vmm_zp_comp()); }
    Vmm vmm_bcast() { return Vmm(vmm_alloc.get_idx_vmm_bcast()); }
    Vmm vmm_tmp(int i) {
        const int idx
                = max_vmms_ - m_block2() * n_block2() * vnni_substep() - 1 - i;
        assert(idx > (is_fast_vnni_int8() - 1));
        return Vmm(idx);
    }

    template <typename U>
    U maybe_mask(const U umm_in, bool mask_flag, bool store);
    void init_masks();
    void read_params();
    void load_permute_vmm();
    void load_accumulators(int m_blocks, int n_blocks);
    void restore_A_B_matrices();
    void set_A_B_matrices();
    void advance_A_B_matrices();
    void load_a(Vmm vmma, int m_i, int n_i, int v_i, bool has_n_tail);
    void load_b(
            Vmm vmmb, int n_i, int v_i, bool has_n_tail, bool wei_zp = false);
    void comp_dot_product(compute_pad_kernel_t kernel_type, Vmm vmm_acc,
            Vmm vmmb, int n,
            bool is_tail_block); // int8 compensation dot_product (zp and s8s8)
    void pad_comp_kernel(compute_pad_kernel_t kernel_type, int m_blocks,
            int n_blocks, int padding, const Xbyak::Reg64 reg_pad,
            const std::function<int(int)> &get_mi, bool has_tail = false);
    void vertical_pad_kernel(int m_blocks, int n_blocks, bool has_tail);
    void batch_pad_kernel(int m_blocks, int n_blocks, bool has_tail = false);
    void brdgmm_microkernel(int m_blocks, int n_blocks, bool has_top_padding,
            bool has_bottom_padding, bool has_tail, int shift_a);
    void compute_loop();
    void get_batch_padding_info();
    void get_vertical_padding_info(const int m_blocks);
    void call_brdgmm_microkernel(const int m_blocks, const int n_blocks,
            bool has_n_tail, int shift_a);
    void batch_loop(const int m_blocks, const int n_blocks, bool has_n_tail);
    void cvt2ps(data_type_t type_in, const Vmm vmm_in, const Xbyak::Operand &op,
            bool mask_flag, bool store);
    void apply_post_ops(int m_blocks, int n_blocks, bool has_n_tail);
    void maybe_transpose_interleaved_vnni_to_plain(
            int m_blocks, int n_blocks, bool has_n_tail);
    void load_src_zp();
    void compute_int8_compensation(int m_blocks, int n_blocks, bool has_n_tail);
    void store_accumulators(int m_blocks, int n_blocks, bool has_n_tail);
    void store_accumulators_without_post_ops(
            int m_blocks, int n_blocks, bool has_n_tail);
    void store_accumulators_apply_post_ops(
            int m_blocks, int n_blocks, bool has_n_tail);
    bool check_effective_padding() { return has_vpad_ && M() > m_block2(); }
    int oc_logical_offset(int n) { return n * n_block1(); }
    int A_offset(int m, int n) {
        return brg.typesize_A * (m * brg.LDA + n * n_block1());
    }
    int B_offset(int n) { return brg.typesize_B * n * n_block1(); }
    int C_offset(int m, int n, int v) {
        return brg.typesize_C * (m * brg.LDC + n * n_block1() + v * simd_w_);
    }
    int D_offset(int m, int n, int v) {
        return brg.typesize_D * (m * brg.LDD + n * n_block1() + v * simd_w_);
    }
    int bias_offset(int n, int v) {
        return brg.typesize_bias * (n * n_block1() + v * simd_w_);
    }
    int wei_scales_offset(int n, int v) {
        return sizeof(float) * brg.is_oc_scale * (n * n_block1() + v * simd_w_);
    }
    size_t comp_offset(int n) { return sizeof(int32_t) * n * n_block1(); }

    void generate() override;
};

} // namespace x64
} // namespace cpu
} // namespace impl
} // namespace dnnl

#endif
