1 /*
2  *  Copyright (c) 2017 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 #include <immintrin.h>  // AVX512
11 #include "./vpx_dsp_rtcd.h"
12 #include "vpx/vpx_integer.h"
13 
vpx_sad64x64x4d_avx512(const uint8_t * src_ptr,int src_stride,const uint8_t * const ref_array[4],int ref_stride,uint32_t res[4])14 void vpx_sad64x64x4d_avx512(const uint8_t *src_ptr, int src_stride,
15                             const uint8_t *const ref_array[4], int ref_stride,
16                             uint32_t res[4]) {
17   __m512i src_reg, ref0_reg, ref1_reg, ref2_reg, ref3_reg;
18   __m512i sum_ref0, sum_ref1, sum_ref2, sum_ref3;
19   __m512i sum_mlow, sum_mhigh;
20   int i;
21   const uint8_t *ref0, *ref1, *ref2, *ref3;
22 
23   ref0 = ref_array[0];
24   ref1 = ref_array[1];
25   ref2 = ref_array[2];
26   ref3 = ref_array[3];
27   sum_ref0 = _mm512_set1_epi16(0);
28   sum_ref1 = _mm512_set1_epi16(0);
29   sum_ref2 = _mm512_set1_epi16(0);
30   sum_ref3 = _mm512_set1_epi16(0);
31   for (i = 0; i < 64; i++) {
32     // load src and all ref[]
33     src_reg = _mm512_loadu_si512((const __m512i *)src_ptr);
34     ref0_reg = _mm512_loadu_si512((const __m512i *)ref0);
35     ref1_reg = _mm512_loadu_si512((const __m512i *)ref1);
36     ref2_reg = _mm512_loadu_si512((const __m512i *)ref2);
37     ref3_reg = _mm512_loadu_si512((const __m512i *)ref3);
38     // sum of the absolute differences between every ref[] to src
39     ref0_reg = _mm512_sad_epu8(ref0_reg, src_reg);
40     ref1_reg = _mm512_sad_epu8(ref1_reg, src_reg);
41     ref2_reg = _mm512_sad_epu8(ref2_reg, src_reg);
42     ref3_reg = _mm512_sad_epu8(ref3_reg, src_reg);
43     // sum every ref[]
44     sum_ref0 = _mm512_add_epi32(sum_ref0, ref0_reg);
45     sum_ref1 = _mm512_add_epi32(sum_ref1, ref1_reg);
46     sum_ref2 = _mm512_add_epi32(sum_ref2, ref2_reg);
47     sum_ref3 = _mm512_add_epi32(sum_ref3, ref3_reg);
48 
49     src_ptr += src_stride;
50     ref0 += ref_stride;
51     ref1 += ref_stride;
52     ref2 += ref_stride;
53     ref3 += ref_stride;
54   }
55   {
56     __m256i sum256;
57     __m128i sum128;
58     // in sum_ref[] the result is saved in the first 4 bytes
59     // the other 4 bytes are zeroed.
60     // sum_ref1 and sum_ref3 are shifted left by 4 bytes
61     sum_ref1 = _mm512_bslli_epi128(sum_ref1, 4);
62     sum_ref3 = _mm512_bslli_epi128(sum_ref3, 4);
63 
64     // merge sum_ref0 and sum_ref1 also sum_ref2 and sum_ref3
65     sum_ref0 = _mm512_or_si512(sum_ref0, sum_ref1);
66     sum_ref2 = _mm512_or_si512(sum_ref2, sum_ref3);
67 
68     // merge every 64 bit from each sum_ref[]
69     sum_mlow = _mm512_unpacklo_epi64(sum_ref0, sum_ref2);
70     sum_mhigh = _mm512_unpackhi_epi64(sum_ref0, sum_ref2);
71 
72     // add the low 64 bit to the high 64 bit
73     sum_mlow = _mm512_add_epi32(sum_mlow, sum_mhigh);
74 
75     // add the low 128 bit to the high 128 bit
76     sum256 = _mm256_add_epi32(_mm512_castsi512_si256(sum_mlow),
77                               _mm512_extracti32x8_epi32(sum_mlow, 1));
78     sum128 = _mm_add_epi32(_mm256_castsi256_si128(sum256),
79                            _mm256_extractf128_si256(sum256, 1));
80 
81     _mm_storeu_si128((__m128i *)(res), sum128);
82   }
83 }
84