/*
* Copyright (c) 2023, Alliance for Open Media. All rights reserved
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/

#include <arm_neon.h>

#include "mem_neon.h"
#include "sum_neon.h"
#include "transpose_neon.h"

static INLINE void sse_16x1_neon(const uint8_t *src, const uint8_t *ref, uint32x4_t *sse) {
    uint8x16_t s = vld1q_u8(src);
    uint8x16_t r = vld1q_u8(ref);

    uint8x16_t abs_diff    = vabdq_u8(s, r);
    uint8x8_t  abs_diff_lo = vget_low_u8(abs_diff);
    uint8x8_t  abs_diff_hi = vget_high_u8(abs_diff);

    *sse = vpadalq_u16(*sse, vmull_u8(abs_diff_lo, abs_diff_lo));
    *sse = vpadalq_u16(*sse, vmull_u8(abs_diff_hi, abs_diff_hi));
}

static INLINE void sse_8x1_neon(const uint8_t *src, const uint8_t *ref, uint32x4_t *sse) {
    uint8x8_t s = vld1_u8(src);
    uint8x8_t r = vld1_u8(ref);

    uint8x8_t abs_diff = vabd_u8(s, r);

    *sse = vpadalq_u16(*sse, vmull_u8(abs_diff, abs_diff));
}

static INLINE void sse_4x2_neon(const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride,
                                uint32x4_t *sse) {
    uint8x8_t s = load_unaligned_u8(src, src_stride);
    uint8x8_t r = load_unaligned_u8(ref, ref_stride);

    uint8x8_t abs_diff = vabd_u8(s, r);

    *sse = vpadalq_u16(*sse, vmull_u8(abs_diff, abs_diff));
}

static INLINE uint32_t sse_wxh_neon(const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride, int width,
                                    int height) {
    uint32x4_t sse = vdupq_n_u32(0);

    if ((width & 0x07) && ((width & 0x07) < 5)) {
        int i = height;
        do {
            int j = 0;
            do {
                sse_8x1_neon(src + j, ref + j, &sse);
                sse_8x1_neon(src + j + src_stride, ref + j + ref_stride, &sse);
                j += 8;
            } while (j + 4 < width);

            sse_4x2_neon(src + j, src_stride, ref + j, ref_stride, &sse);
            src += 2 * src_stride;
            ref += 2 * ref_stride;
            i -= 2;
        } while (i != 0);
    } else {
        int i = height;
        do {
            int j = 0;
            do {
                sse_8x1_neon(src + j, ref + j, &sse);
                j += 8;
            } while (j < width);

            src += src_stride;
            ref += ref_stride;
        } while (--i != 0);
    }
    return horizontal_add_u32x4(sse);
}

static INLINE uint32_t sse_128xh_neon(const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride,
                                      int height) {
    uint32x4_t sse[2] = {vdupq_n_u32(0), vdupq_n_u32(0)};

    int i = height;
    do {
        sse_16x1_neon(src, ref, &sse[0]);
        sse_16x1_neon(src + 16, ref + 16, &sse[1]);
        sse_16x1_neon(src + 32, ref + 32, &sse[0]);
        sse_16x1_neon(src + 48, ref + 48, &sse[1]);
        sse_16x1_neon(src + 64, ref + 64, &sse[0]);
        sse_16x1_neon(src + 80, ref + 80, &sse[1]);
        sse_16x1_neon(src + 96, ref + 96, &sse[0]);
        sse_16x1_neon(src + 112, ref + 112, &sse[1]);

        src += src_stride;
        ref += ref_stride;
    } while (--i != 0);

    return horizontal_add_u32x4(vaddq_u32(sse[0], sse[1]));
}

static INLINE uint32_t sse_64xh_neon(const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride,
                                     int height) {
    uint32x4_t sse[2] = {vdupq_n_u32(0), vdupq_n_u32(0)};

    int i = height;
    do {
        sse_16x1_neon(src, ref, &sse[0]);
        sse_16x1_neon(src + 16, ref + 16, &sse[1]);
        sse_16x1_neon(src + 32, ref + 32, &sse[0]);
        sse_16x1_neon(src + 48, ref + 48, &sse[1]);

        src += src_stride;
        ref += ref_stride;
    } while (--i != 0);

    return horizontal_add_u32x4(vaddq_u32(sse[0], sse[1]));
}

static INLINE uint32_t sse_32xh_neon(const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride,
                                     int height) {
    uint32x4_t sse[2] = {vdupq_n_u32(0), vdupq_n_u32(0)};

    int i = height;
    do {
        sse_16x1_neon(src, ref, &sse[0]);
        sse_16x1_neon(src + 16, ref + 16, &sse[1]);

        src += src_stride;
        ref += ref_stride;
    } while (--i != 0);

    return horizontal_add_u32x4(vaddq_u32(sse[0], sse[1]));
}

static INLINE uint32_t sse_16xh_neon(const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride,
                                     int height) {
    uint32x4_t sse[2] = {vdupq_n_u32(0), vdupq_n_u32(0)};

    int i = height;
    do {
        sse_16x1_neon(src, ref, &sse[0]);
        src += src_stride;
        ref += ref_stride;
        sse_16x1_neon(src, ref, &sse[1]);
        src += src_stride;
        ref += ref_stride;
        i -= 2;
    } while (i != 0);

    return horizontal_add_u32x4(vaddq_u32(sse[0], sse[1]));
}

static INLINE uint32_t sse_8xh_neon(const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride,
                                    int height) {
    uint32x4_t sse = vdupq_n_u32(0);

    int i = height;
    do {
        sse_8x1_neon(src, ref, &sse);

        src += src_stride;
        ref += ref_stride;
    } while (--i != 0);

    return horizontal_add_u32x4(sse);
}

static INLINE uint32_t sse_4xh_neon(const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride,
                                    int height) {
    uint32x4_t sse = vdupq_n_u32(0);

    int i = height;
    do {
        sse_4x2_neon(src, src_stride, ref, ref_stride, &sse);

        src += 2 * src_stride;
        ref += 2 * ref_stride;
        i -= 2;
    } while (i != 0);

    return horizontal_add_u32x4(sse);
}

uint64_t svt_spatial_full_distortion_kernel_neon(uint8_t *src, uint32_t src_offset, uint32_t src_stride, uint8_t *ref,
                                                 uint32_t ref_offset, uint32_t ref_stride, uint32_t width,
                                                 uint32_t height) {
    src += src_offset;
    ref += ref_offset;
    switch (width) {
    case 4: return sse_4xh_neon(src, src_stride, ref, ref_stride, height);
    case 8: return sse_8xh_neon(src, src_stride, ref, ref_stride, height);
    case 16: return sse_16xh_neon(src, src_stride, ref, ref_stride, height);
    case 32: return sse_32xh_neon(src, src_stride, ref, ref_stride, height);
    case 64: return sse_64xh_neon(src, src_stride, ref, ref_stride, height);
    case 128: return sse_128xh_neon(src, src_stride, ref, ref_stride, height);
    default: return sse_wxh_neon(src, src_stride, ref, ref_stride, width, height);
    }
}

#if CONFIG_AV1_HIGHBITDEPTH
static INLINE uint32_t highbd_sse_W8x1_neon(uint16x8_t q2, uint16x8_t q3) {
    uint32_t         sse;
    const uint32_t   sse1 = 0;
    const uint32x4_t q1   = vld1q_dup_u32(&sse1);

    uint16x8_t q4 = vabdq_u16(q2, q3); // diff = abs(a[x] - b[x])
    uint16x4_t d0 = vget_low_u16(q4);
    uint16x4_t d1 = vget_high_u16(q4);

    uint32x4_t q6 = vmlal_u16(q1, d0, d0);
    uint32x4_t q7 = vmlal_u16(q1, d1, d1);

    uint32x2_t d4 = vadd_u32(vget_low_u32(q6), vget_high_u32(q6));
    uint32x2_t d5 = vadd_u32(vget_low_u32(q7), vget_high_u32(q7));

    uint32x2_t d6 = vadd_u32(d4, d5);

    sse = vget_lane_u32(d6, 0);
    sse += vget_lane_u32(d6, 1);

    return sse;
}

int64_t aom_highbd_sse_neon(const uint8_t *a8, int a_stride, const uint8_t *b8, int b_stride, int width, int height) {
    static const uint16_t k01234567[8] = {0, 1, 2, 3, 4, 5, 6, 7};
    const uint16x8_t      q0           = vld1q_u16(k01234567);
    int64_t               sse          = 0;
    uint16_t             *a            = CONVERT_TO_SHORTPTR(a8);
    uint16_t             *b            = CONVERT_TO_SHORTPTR(b8);
    int                   x, y;
    int                   addinc;
    uint16x4_t            d0, d1, d2, d3;
    uint16_t              dx;
    uint16x8_t            q2, q3, q4, q5;

    switch (width) {
    case 4:
        for (y = 0; y < height; y += 2) {
            d0 = vld1_u16(a); // load 4 data
            a += a_stride;
            d1 = vld1_u16(a);
            a += a_stride;

            d2 = vld1_u16(b);
            b += b_stride;
            d3 = vld1_u16(b);
            b += b_stride;
            q2 = vcombine_u16(d0, d1); // make a 8 data vector
            q3 = vcombine_u16(d2, d3);

            sse += highbd_sse_W8x1_neon(q2, q3);
        }
        break;
    case 8:
        for (y = 0; y < height; y++) {
            q2 = vld1q_u16(a);
            q3 = vld1q_u16(b);

            sse += highbd_sse_W8x1_neon(q2, q3);

            a += a_stride;
            b += b_stride;
        }
        break;
    case 16:
        for (y = 0; y < height; y++) {
            q2 = vld1q_u16(a);
            q3 = vld1q_u16(b);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 8);
            q3 = vld1q_u16(b + 8);

            sse += highbd_sse_W8x1_neon(q2, q3);

            a += a_stride;
            b += b_stride;
        }
        break;
    case 32:
        for (y = 0; y < height; y++) {
            q2 = vld1q_u16(a);
            q3 = vld1q_u16(b);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 8);
            q3 = vld1q_u16(b + 8);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 16);
            q3 = vld1q_u16(b + 16);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 24);
            q3 = vld1q_u16(b + 24);

            sse += highbd_sse_W8x1_neon(q2, q3);

            a += a_stride;
            b += b_stride;
        }
        break;
    case 64:
        for (y = 0; y < height; y++) {
            q2 = vld1q_u16(a);
            q3 = vld1q_u16(b);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 8);
            q3 = vld1q_u16(b + 8);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 16);
            q3 = vld1q_u16(b + 16);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 24);
            q3 = vld1q_u16(b + 24);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 32);
            q3 = vld1q_u16(b + 32);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 40);
            q3 = vld1q_u16(b + 40);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 48);
            q3 = vld1q_u16(b + 48);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 56);
            q3 = vld1q_u16(b + 56);

            sse += highbd_sse_W8x1_neon(q2, q3);

            a += a_stride;
            b += b_stride;
        }
        break;
    case 128:
        for (y = 0; y < height; y++) {
            q2 = vld1q_u16(a);
            q3 = vld1q_u16(b);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 8);
            q3 = vld1q_u16(b + 8);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 16);
            q3 = vld1q_u16(b + 16);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 24);
            q3 = vld1q_u16(b + 24);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 32);
            q3 = vld1q_u16(b + 32);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 40);
            q3 = vld1q_u16(b + 40);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 48);
            q3 = vld1q_u16(b + 48);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 56);
            q3 = vld1q_u16(b + 56);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 64);
            q3 = vld1q_u16(b + 64);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 72);
            q3 = vld1q_u16(b + 72);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 80);
            q3 = vld1q_u16(b + 80);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 88);
            q3 = vld1q_u16(b + 88);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 96);
            q3 = vld1q_u16(b + 96);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 104);
            q3 = vld1q_u16(b + 104);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 112);
            q3 = vld1q_u16(b + 112);

            sse += highbd_sse_W8x1_neon(q2, q3);

            q2 = vld1q_u16(a + 120);
            q3 = vld1q_u16(b + 120);

            sse += highbd_sse_W8x1_neon(q2, q3);
            a += a_stride;
            b += b_stride;
        }
        break;
    default:

        for (y = 0; y < height; y++) {
            x = width;
            while (x > 0) {
                addinc = width - x;
                q2     = vld1q_u16(a + addinc);
                q3     = vld1q_u16(b + addinc);
                if (x < 8) {
                    dx = x;
                    q4 = vld1q_dup_u16(&dx);
                    q5 = vcltq_u16(q0, q4);
                    q2 = vandq_u16(q2, q5);
                    q3 = vandq_u16(q3, q5);
                }
                sse += highbd_sse_W8x1_neon(q2, q3);
                x -= 8;
            }
            a += a_stride;
            b += b_stride;
        }
    }
    return (int64_t)sse;
}
#endif
