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
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
std::pair<const char *, char32_t *>
lasx_convert_latin1_to_utf32(const char *buf, size_t len,
char32_t *utf32_output) {
const char *end = buf + len;
// LASX requires 32-byte alignment, otherwise performance will be degraded
while (((uint64_t)utf32_output & 0x1F) && buf < end) {
*utf32_output++ = ((uint32_t)*buf) & 0xFF;
buf++;
}
while (buf + 32 <= end) {
__m256i in8 = __lasx_xvld(reinterpret_cast<const uint8_t *>(buf), 0);
__m256i in32_0 = __lasx_vext2xv_wu_bu(in8);
__lasx_xvst(in32_0, reinterpret_cast<uint32_t *>(utf32_output), 0);
__m256i in8_1 = __lasx_xvpermi_d(in8, 0b00000001);
__m256i in32_1 = __lasx_vext2xv_wu_bu(in8_1);
__lasx_xvst(in32_1, reinterpret_cast<uint32_t *>(utf32_output), 32);
__m256i in8_2 = __lasx_xvpermi_d(in8, 0b00000010);
__m256i in32_2 = __lasx_vext2xv_wu_bu(in8_2);
__lasx_xvst(in32_2, reinterpret_cast<uint32_t *>(utf32_output), 64);
__m256i in8_3 = __lasx_xvpermi_d(in8, 0b00000011);
__m256i in32_3 = __lasx_vext2xv_wu_bu(in8_3);
__lasx_xvst(in32_3, reinterpret_cast<uint32_t *>(utf32_output), 96);
utf32_output += 32;
buf += 32;
}
if (buf + 16 <= end) {
__m128i in8 = __lsx_vld(reinterpret_cast<const uint8_t *>(buf), 0);
__m128i zero = __lsx_vldi(0);
__m128i in16low = __lsx_vilvl_b(zero, in8);
__m128i in16high = __lsx_vilvh_b(zero, in8);
__m128i in32_0 = __lsx_vilvl_h(zero, in16low);
__m128i in32_1 = __lsx_vilvh_h(zero, in16low);
__m128i in32_2 = __lsx_vilvl_h(zero, in16high);
__m128i in32_3 = __lsx_vilvh_h(zero, in16high);
__lsx_vst(in32_0, reinterpret_cast<uint32_t *>(utf32_output), 0);
__lsx_vst(in32_1, reinterpret_cast<uint32_t *>(utf32_output), 16);
__lsx_vst(in32_2, reinterpret_cast<uint32_t *>(utf32_output), 32);
__lsx_vst(in32_3, reinterpret_cast<uint32_t *>(utf32_output), 48);
utf32_output += 16;
buf += 16;
}
return std::make_pair(buf, utf32_output);
}
|
