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
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
|
#include <util/charset/wide.h>
#include <util/system/types.h>
#ifdef SSE41_STUB
namespace NDetail {
void UTF8ToWideImplSSE41(const unsigned char*&, const unsigned char*, wchar16*&) noexcept {
}
void UTF8ToWideImplSSE41(const unsigned char*&, const unsigned char*, wchar32*&) noexcept {
}
}
#else
#include <util/system/compiler.h>
#include <cstring>
#include <emmintrin.h>
#include <smmintrin.h>
// processes to the first error, or until less then 16 bytes left
// most code taken from https://woboq.com/blog/utf-8-processing-using-simd.html
// return dstAdvance 0 in case of problems
static Y_FORCE_INLINE ui32 Unpack16BytesIntoUtf16IfNoSurrogats(const unsigned char*& cur, __m128i& utf16Low, __m128i& utf16High) {
unsigned char curAligned[16];
memcpy(curAligned, cur, sizeof(__m128i));
__m128i chunk = _mm_load_si128(reinterpret_cast<const __m128i*>(curAligned));
// only ascii characters - simple copy
if (!_mm_movemask_epi8(chunk)) {
utf16Low = _mm_unpacklo_epi8(chunk, _mm_setzero_si128());
utf16High = _mm_unpackhi_epi8(chunk, _mm_setzero_si128());
cur += 16;
return 16;
}
__m128i chunkSigned = _mm_add_epi8(chunk, _mm_set1_epi8(0x80));
__m128i isAsciiMask = _mm_cmpgt_epi8(chunk, _mm_set1_epi8(0));
__m128i cond2 = _mm_cmplt_epi8(_mm_set1_epi8(0xc2 - 1 - 0x80), chunkSigned);
__m128i state = _mm_set1_epi8(0x0 | (char)0x80);
__m128i cond3 = _mm_cmplt_epi8(_mm_set1_epi8(0xe0 - 1 - 0x80), chunkSigned);
state = _mm_blendv_epi8(state, _mm_set1_epi8(0x2 | (char)0xc0), cond2);
int sourceAdvance;
__m128i shifts;
__m128i chunkLow, chunkHigh;
if (Y_LIKELY(!_mm_movemask_epi8(cond3))) {
// main case: no bloks of size 3 or 4
// rune len for start of multi-byte sequences (0 for b0... and b10..., 2 for b110..., etc.)
__m128i count = _mm_and_si128(state, _mm_set1_epi8(0x7));
__m128i countSub1 = _mm_subs_epu8(count, _mm_set1_epi8(0x1));
shifts = countSub1;
__m128i continuation1 = _mm_slli_si128(countSub1, 1);
shifts = _mm_add_epi8(shifts, _mm_slli_si128(shifts, 1));
shifts = _mm_add_epi8(shifts, _mm_slli_si128(shifts, 2));
__m128i counts = _mm_or_si128(count, continuation1);
__m128i isBeginMultibyteMask = _mm_cmpgt_epi8(count, _mm_set1_epi8(0));
__m128i needNoContinuationMask = _mm_cmpeq_epi8(continuation1, _mm_set1_epi8(0));
__m128i isBeginMask = _mm_add_epi8(isBeginMultibyteMask, isAsciiMask);
// each symbol should be exactly one of ascii, continuation or begin
__m128i okMask = _mm_cmpeq_epi8(isBeginMask, needNoContinuationMask);
if (_mm_movemask_epi8(okMask) != 0xFFFF) {
return 0;
}
shifts = _mm_add_epi8(shifts, _mm_slli_si128(shifts, 4));
__m128i mask = _mm_and_si128(state, _mm_set1_epi8(0xf8));
shifts = _mm_add_epi8(shifts, _mm_slli_si128(shifts, 8));
chunk = _mm_andnot_si128(mask, chunk); // from now on, we only have usefull bits
shifts = _mm_and_si128(shifts, _mm_cmplt_epi8(counts, _mm_set1_epi8(2))); // <=1
__m128i chunk_right = _mm_slli_si128(chunk, 1);
shifts = _mm_blendv_epi8(shifts, _mm_srli_si128(shifts, 1),
_mm_srli_si128(_mm_slli_epi16(shifts, 7), 1));
chunkLow = _mm_blendv_epi8(chunk,
_mm_or_si128(chunk, _mm_and_si128(_mm_slli_epi16(chunk_right, 6), _mm_set1_epi8(0xc0))),
_mm_cmpeq_epi8(counts, _mm_set1_epi8(1)));
chunkHigh = _mm_and_si128(chunk, _mm_cmpeq_epi8(counts, _mm_set1_epi8(2)));
shifts = _mm_blendv_epi8(shifts, _mm_srli_si128(shifts, 2),
_mm_srli_si128(_mm_slli_epi16(shifts, 6), 2));
chunkHigh = _mm_srli_epi32(chunkHigh, 2);
shifts = _mm_blendv_epi8(shifts, _mm_srli_si128(shifts, 4),
_mm_srli_si128(_mm_slli_epi16(shifts, 5), 4));
int c = _mm_extract_epi16(counts, 7);
sourceAdvance = !(c & 0x0200) ? 16 : 15;
} else {
__m128i mask3 = _mm_slli_si128(cond3, 1);
__m128i cond4 = _mm_cmplt_epi8(_mm_set1_epi8(0xf0 - 1 - 0x80), chunkSigned);
state = _mm_blendv_epi8(state, _mm_set1_epi8(0x3 | (char)0xe0), cond3);
// 4 bytes sequences are not vectorize. Fall back to the scalar processing
if (Y_UNLIKELY(_mm_movemask_epi8(cond4))) {
return 0;
}
// rune len for start of multi-byte sequences (0 for b0... and b10..., 2 for b110..., etc.)
__m128i count = _mm_and_si128(state, _mm_set1_epi8(0x7));
__m128i countSub1 = _mm_subs_epu8(count, _mm_set1_epi8(0x1));
__m128i continuation2 = _mm_slli_si128(_mm_subs_epu8(count, _mm_set1_epi8(0x2)), 2);
shifts = countSub1;
__m128i continuation1 = _mm_slli_si128(countSub1, 1);
shifts = _mm_add_epi8(shifts, _mm_slli_si128(shifts, 1));
__m128i continuationsRunelen = _mm_or_si128(continuation1, continuation2);
shifts = _mm_add_epi8(shifts, _mm_slli_si128(shifts, 2));
__m128i counts = _mm_or_si128(count, continuationsRunelen);
__m128i isBeginMultibyteMask = _mm_cmpgt_epi8(count, _mm_set1_epi8(0));
__m128i needNoContinuationMask = _mm_cmpeq_epi8(continuationsRunelen, _mm_set1_epi8(0));
__m128i isBeginMask = _mm_add_epi8(isBeginMultibyteMask, isAsciiMask);
// each symbol should be exactly one of ascii, continuation or begin
__m128i okMask = _mm_cmpeq_epi8(isBeginMask, needNoContinuationMask);
if (_mm_movemask_epi8(okMask) != 0xFFFF) {
return 0;
}
shifts = _mm_add_epi8(shifts, _mm_slli_si128(shifts, 4));
__m128i mask = _mm_and_si128(state, _mm_set1_epi8(0xf8));
shifts = _mm_add_epi8(shifts, _mm_slli_si128(shifts, 8));
chunk = _mm_andnot_si128(mask, chunk); // from now on, we only have usefull bits
shifts = _mm_and_si128(shifts, _mm_cmplt_epi8(counts, _mm_set1_epi8(2))); // <=1
__m128i chunk_right = _mm_slli_si128(chunk, 1);
shifts = _mm_blendv_epi8(shifts, _mm_srli_si128(shifts, 1),
_mm_srli_si128(_mm_slli_epi16(shifts, 7), 1));
chunkLow = _mm_blendv_epi8(chunk,
_mm_or_si128(chunk, _mm_and_si128(_mm_slli_epi16(chunk_right, 6), _mm_set1_epi8(0xc0))),
_mm_cmpeq_epi8(counts, _mm_set1_epi8(1)));
chunkHigh = _mm_and_si128(chunk, _mm_cmpeq_epi8(counts, _mm_set1_epi8(2)));
shifts = _mm_blendv_epi8(shifts, _mm_srli_si128(shifts, 2),
_mm_srli_si128(_mm_slli_epi16(shifts, 6), 2));
chunkHigh = _mm_srli_epi32(chunkHigh, 2);
shifts = _mm_blendv_epi8(shifts, _mm_srli_si128(shifts, 4),
_mm_srli_si128(_mm_slli_epi16(shifts, 5), 4));
chunkHigh = _mm_or_si128(chunkHigh,
_mm_and_si128(_mm_and_si128(_mm_slli_epi32(chunk_right, 4), _mm_set1_epi8(0xf0)),
mask3));
int c = _mm_extract_epi16(counts, 7);
sourceAdvance = !(c & 0x0200) ? 16 : !(c & 0x02) ? 15
: 14;
}
shifts = _mm_blendv_epi8(shifts, _mm_srli_si128(shifts, 8),
_mm_srli_si128(_mm_slli_epi16(shifts, 4), 8));
chunkHigh = _mm_slli_si128(chunkHigh, 1);
__m128i shuf = _mm_add_epi8(shifts, _mm_set_epi8(15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0));
chunkLow = _mm_shuffle_epi8(chunkLow, shuf);
chunkHigh = _mm_shuffle_epi8(chunkHigh, shuf);
utf16Low = _mm_unpacklo_epi8(chunkLow, chunkHigh);
utf16High = _mm_unpackhi_epi8(chunkLow, chunkHigh);
ui32 s = _mm_extract_epi32(shifts, 3);
ui32 destAdvance = sourceAdvance - (0xff & (s >> (8 * (3 - 16 + sourceAdvance))));
cur += sourceAdvance;
return destAdvance;
}
namespace NDetail {
void UTF8ToWideImplSSE41(const unsigned char*& cur, const unsigned char* last, wchar16*& dest) noexcept {
alignas(16) wchar16 destAligned[16];
while (cur + 16 <= last) {
__m128i utf16Low;
__m128i utf16High;
ui32 dstAdvance = Unpack16BytesIntoUtf16IfNoSurrogats(cur, utf16Low, utf16High);
if (dstAdvance == 0) {
break;
}
_mm_store_si128(reinterpret_cast<__m128i*>(destAligned), utf16Low);
_mm_store_si128(reinterpret_cast<__m128i*>(destAligned) + 1, utf16High);
memcpy(dest, destAligned, sizeof(__m128i) * 2);
dest += dstAdvance;
}
// The rest will be handled sequencially.
// Possible improvement: go back to the vectorized processing after the error or the 4 byte sequence
}
void UTF8ToWideImplSSE41(const unsigned char*& cur, const unsigned char* last, wchar32*& dest) noexcept {
alignas(16) wchar32 destAligned[16];
while (cur + 16 <= last) {
__m128i utf16Low;
__m128i utf16High;
ui32 dstAdvance = Unpack16BytesIntoUtf16IfNoSurrogats(cur, utf16Low, utf16High);
if (dstAdvance == 0) {
break;
}
// NOTE: we only work in case without surrogat pairs, so we can make simple copying with zeroes in 2 high bytes
__m128i utf32_lowlow = _mm_unpacklo_epi16(utf16Low, _mm_set1_epi8(0));
__m128i utf32_lowhigh = _mm_unpackhi_epi16(utf16Low, _mm_set1_epi8(0));
__m128i utf32_highlow = _mm_unpacklo_epi16(utf16High, _mm_set1_epi8(0));
__m128i utf32_highhigh = _mm_unpackhi_epi16(utf16High, _mm_set1_epi8(0));
_mm_store_si128(reinterpret_cast<__m128i*>(destAligned), utf32_lowlow);
_mm_store_si128(reinterpret_cast<__m128i*>(destAligned) + 1, utf32_lowhigh);
_mm_store_si128(reinterpret_cast<__m128i*>(destAligned) + 2, utf32_highlow);
_mm_store_si128(reinterpret_cast<__m128i*>(destAligned) + 3, utf32_highhigh);
memcpy(dest, destAligned, sizeof(__m128i) * 4);
dest += dstAdvance;
}
// The rest will be handled sequencially.
// Possible improvement: go back to the vectorized processing after the error or the 4 byte sequence
}
}
#endif
|
