/*******************************************************************************
* Copyright 2016-2018 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.
*******************************************************************************/

#include "c_types_map.hpp"
#include "type_helpers.hpp"
#include "mkldnn_thread.hpp"
#include "mkldnn_traits.hpp"
#include "math_utils.hpp"

#include "ref_inner_product.hpp"

namespace mkldnn {
namespace impl {
namespace cpu {

using math::saturate;
using math::get_bias;

template <data_type_t src_type, data_type_t wei_type, data_type_t dst_type,
         data_type_t acc_type>
void ref_inner_product_fwd_t<src_type, wei_type, dst_type, acc_type>
        ::execute_forward() const {
    auto src = reinterpret_cast<const src_data_t *>(this->input_memory(0));
    auto weights = reinterpret_cast<const wei_data_t *>(this->input_memory(1));
    auto bias = reinterpret_cast<const char *>(this->input_memory(2));
    auto dst = reinterpret_cast<dst_data_t *>(this->memory());

    const memory_desc_wrapper src_d(pd()->src_pd());
    const memory_desc_wrapper dst_d(pd()->dst_pd());
    const memory_desc_wrapper weights_d(pd()->weights_pd(0));
    const memory_desc_wrapper bias_d(pd()->weights_pd(1));

    const int MB = pd()->MB();
    const int OC = pd()->OC();
    const int IC = pd()->IC();

    const bool src_has_spatial = utils::one_of(src_d.ndims(), 4, 5);

    const bool is_3d = src_d.ndims() == 5;

    const auto &post_ops = pd()->attr()->post_ops_;
    const bool do_relu = post_ops.len_ == 1;
    const float nslope = do_relu ? post_ops.entry_[0].eltwise.alpha : 0.f;

    auto ker_has_spatial = [=](int mb, int oc) {
        acc_data_t d = 0;
        const int KD = pd()->KD();
        const int KH = pd()->KH();
        const int KW = pd()->KW();
        for (int ic = 0; ic < IC; ++ic) {
            for (int kd = 0; kd < KD; ++kd) {
                for (int kh = 0; kh < KH; ++kh) {
                    for (int kw = 0; kw < KW; ++kw) {
                        if (is_3d)
                            d += (acc_data_t)src[src_d.off(mb, ic, kd, kh, kw)]
                                * weights[weights_d.off(oc, ic, kd, kh, kw)];
                        else
                            d += (acc_data_t)src[src_d.off(mb, ic, kh, kw)]
                                * weights[weights_d.off(oc, ic, kh, kw)];
                    }
                }
            }
        }
        return d;
    };

    auto ker_no_spatial = [=](int mb, int oc) {
        acc_data_t d = 0;
        for (int ic = 0; ic < IC; ++ic) {
            d += (acc_data_t)src[src_d.off(mb, ic)]
                * weights[weights_d.off(oc, ic)];
        }
        return d;
    };

    parallel_nd(MB, OC, [&](int mb, int oc) {
        float a = bias
            ? get_bias(bias, bias_d.off(oc), pd()->desc()->bias_desc.data_type)
            : 0;
        if (src_has_spatial)
            a += ker_has_spatial(mb, oc);
        else
            a += ker_no_spatial(mb, oc);
        if (do_relu && a < (acc_data_t)0)
            a *= nslope;
        dst[dst_d.off(mb, oc)] = saturate<dst_data_t>(a);
    });
}
using namespace data_type;
template struct ref_inner_product_fwd_t<f32>;
template struct ref_inner_product_fwd_t<s16, s16, s32, s32>;
template struct ref_inner_product_fwd_t<u8, s8, f32, s32>;
template struct ref_inner_product_fwd_t<u8, s8, s32, s32>;
template struct ref_inner_product_fwd_t<u8, s8, s8, s32>;
template struct ref_inner_product_fwd_t<u8, s8, u8, s32>;

template <data_type_t diff_src_type, data_type_t wei_type,
         data_type_t diff_dst_type, data_type_t acc_type>
void ref_inner_product_bwd_data_t<diff_src_type, wei_type, diff_dst_type,
     acc_type>::execute_backward_data() const {
    auto diff_dst = reinterpret_cast<const diff_dst_data_t *>(
            this->input_memory(0));
    auto weights = reinterpret_cast<const wei_data_t *>(this->input_memory(1));
    auto diff_src = reinterpret_cast<diff_src_data_t*>(this->memory());

    const memory_desc_wrapper diff_dst_d(pd()->diff_dst_pd());
    const memory_desc_wrapper weights_d(pd()->weights_pd(0));
    const memory_desc_wrapper diff_src_d(pd()->diff_src_pd());

    const int MB = pd()->MB();
    const int OC = pd()->OC();
    const int IC = pd()->IC();

    const bool diff_src_has_spatial = utils::one_of(diff_src_d.ndims(), 4, 5);

    const bool is_3d = diff_src_d.ndims() == 5;

    parallel_nd(MB, IC, [&](int mb, int ic) {
        if (diff_src_has_spatial) {
            const int KD = pd()->KD();
            const int KH = pd()->KH();
            const int KW = pd()->KW();
            for (int kd = 0; kd < KD; ++kd)
            for (int kh = 0; kh < KH; ++kh)
            for (int kw = 0; kw < KW; ++kw) {
                acc_data_t ds = acc_data_t(0);
                for (int oc = 0; oc < OC; ++oc) {
                    if (is_3d)
                        ds += (acc_data_t)(diff_dst[diff_dst_d.off(mb, oc)]
                            * weights[weights_d.off(oc, ic, kd, kh, kw)]);
                    else
                        ds += (acc_data_t)(diff_dst[diff_dst_d.off(mb, oc)]
                            * weights[weights_d.off(oc, ic, kh, kw)]);
                }
                if (is_3d) diff_src[diff_src_d.off(mb, ic, kd, kh, kw)] =
                    (diff_src_data_t)ds;
                else diff_src[diff_src_d.off(mb, ic, kh, kw)] =
                    (diff_src_data_t)ds;
            }
        } else {
            acc_data_t ds = acc_data_t(0);
            for (int oc = 0; oc < OC; ++oc) {
                ds += (acc_data_t)(diff_dst[diff_dst_d.off(mb, oc)] *
                    weights[weights_d.off(oc, ic)]);
            }
            diff_src[diff_src_d.off(mb, ic)] = (diff_src_data_t)ds;
        }
    });
}

template struct ref_inner_product_bwd_data_t<f32, f32, f32, f32>;
template struct ref_inner_product_bwd_data_t<s32, s16, s16, s32>;

template <impl::data_type_t data_type>
void ref_inner_product_bwd_weights_t<data_type>::execute_backward_weights() const {
    auto src = reinterpret_cast<const data_t *>(this->input_memory(0));
    auto diff_dst = reinterpret_cast<const data_t *>(this->input_memory(1));
    auto diff_weights = reinterpret_cast<data_t*>(this->memory(0));
    auto diff_bias = reinterpret_cast<data_t*>(this->memory(1));

    const memory_desc_wrapper src_d(pd()->src_pd());
    const memory_desc_wrapper diff_dst_d(pd()->diff_dst_pd());
    const memory_desc_wrapper diff_weights_d(pd()->diff_weights_pd(0));
    const memory_desc_wrapper diff_bias_d(pd()->diff_weights_pd(1));

    const int MB = pd()->MB();
    const int OC = pd()->OC();
    const int IC = pd()->IC();

    const bool src_has_spatial = utils::one_of(src_d.ndims(), 4 ,5);

    const bool is_3d = src_d.ndims() == 5;

    parallel_nd(OC, IC, [&](int oc, int ic) {
        if (src_has_spatial) {
            const int KD = pd()->KD();
            const int KH = pd()->KH();
            const int KW = pd()->KW();
            for (int kd = 0; kd < KD; ++kd) {
                for (int kh = 0; kh < KH; ++kh) {
                    for (int kw = 0; kw < KW; ++kw) {
                        data_t *dw = is_3d
                            ? &diff_weights[
                            diff_weights_d.off(oc, ic, kd, kh, kw)]
                            : &diff_weights[
                            diff_weights_d.off(oc, ic, kh, kw)];
                        *dw = data_t(0);
                        for (int mb = 0; mb < MB; ++mb) {
                            if (is_3d)
                                *dw += diff_dst[diff_dst_d.off(mb, oc)] *
                                    src[src_d.off(mb, ic, kd, kh, kw)];
                            else
                                *dw += diff_dst[diff_dst_d.off(mb, oc)] *
                                    src[src_d.off(mb, ic, kh, kw)];
                        }
                    }
                }
            }
        } else {
            data_t *dw = &diff_weights[diff_weights_d.off(oc, ic)];
            *dw = data_t(0);
            for (int mb = 0; mb < MB; ++mb) {
                *dw += diff_dst[diff_dst_d.off(mb, oc)] *
                    src[src_d.off(mb, ic)];
            }
        }
    });

    if (diff_bias) {
        diff_bias += diff_bias_d.blocking_desc().offset_padding;

        parallel_nd(OC, [&](int oc) {
            data_t *db = &diff_bias[oc];
            *db = data_t(0);
            for (int mb = 0; mb < MB; ++mb)
                *db += diff_dst[diff_dst_d.off(mb, oc)];
        });
    }
}

template struct ref_inner_product_bwd_weights_t<data_type::f32>;

}
}
}

// vim: et ts=4 sw=4 cindent cino^=l0,\:0,N-s
