1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
|
static inline __m256i
dec_reshuffle (const __m256i in)
{
// in, lower lane, bits, upper case are most significant bits, lower
// case are least significant bits:
// 00llllll 00kkkkLL 00jjKKKK 00JJJJJJ
// 00iiiiii 00hhhhII 00ggHHHH 00GGGGGG
// 00ffffff 00eeeeFF 00ddEEEE 00DDDDDD
// 00cccccc 00bbbbCC 00aaBBBB 00AAAAAA
const __m256i merge_ab_and_bc = _mm256_maddubs_epi16(in, _mm256_set1_epi32(0x01400140));
// 0000kkkk LLllllll 0000JJJJ JJjjKKKK
// 0000hhhh IIiiiiii 0000GGGG GGggHHHH
// 0000eeee FFffffff 0000DDDD DDddEEEE
// 0000bbbb CCcccccc 0000AAAA AAaaBBBB
__m256i out = _mm256_madd_epi16(merge_ab_and_bc, _mm256_set1_epi32(0x00011000));
// 00000000 JJJJJJjj KKKKkkkk LLllllll
// 00000000 GGGGGGgg HHHHhhhh IIiiiiii
// 00000000 DDDDDDdd EEEEeeee FFffffff
// 00000000 AAAAAAaa BBBBbbbb CCcccccc
// Pack bytes together in each lane:
out = _mm256_shuffle_epi8(out, _mm256_setr_epi8(
2, 1, 0, 6, 5, 4, 10, 9, 8, 14, 13, 12, -1, -1, -1, -1,
2, 1, 0, 6, 5, 4, 10, 9, 8, 14, 13, 12, -1, -1, -1, -1));
// 00000000 00000000 00000000 00000000
// LLllllll KKKKkkkk JJJJJJjj IIiiiiii
// HHHHhhhh GGGGGGgg FFffffff EEEEeeee
// DDDDDDdd CCcccccc BBBBbbbb AAAAAAaa
// Pack lanes:
return _mm256_permutevar8x32_epi32(out, _mm256_setr_epi32(0, 1, 2, 4, 5, 6, -1, -1));
}
|
