1 /*
2 * Process 2x16 bytes in each iteration.
3 * Comments removed for brevity. See range-sse.c for details.
4 */
5 #ifdef __SSE4_1__
6
7 #include <stdio.h>
8 #include <stdint.h>
9 #include <x86intrin.h>
10
11 int utf8_naive(const unsigned char *data, int len);
12
13 static const int8_t _first_len_tbl[] = {
14 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 3,
15 };
16
17 static const int8_t _first_range_tbl[] = {
18 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8,
19 };
20
21 static const int8_t _range_min_tbl[] = {
22 0x00, 0x80, 0x80, 0x80, 0xA0, 0x80, 0x90, 0x80,
23 0xC2, 0x7F, 0x7F, 0x7F, 0x7F, 0x7F, 0x7F, 0x7F,
24 };
25 static const int8_t _range_max_tbl[] = {
26 0x7F, 0xBF, 0xBF, 0xBF, 0xBF, 0x9F, 0xBF, 0x8F,
27 0xF4, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
28 };
29
30 static const int8_t _df_ee_tbl[] = {
31 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0,
32 };
33 static const int8_t _ef_fe_tbl[] = {
34 0, 3, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
35 };
36
37 /* Return 0 on success, -1 on error */
utf8_range2(const unsigned char * data,int len)38 int utf8_range2(const unsigned char *data, int len)
39 {
40 if (len >= 32) {
41 __m128i prev_input = _mm_set1_epi8(0);
42 __m128i prev_first_len = _mm_set1_epi8(0);
43
44 const __m128i first_len_tbl =
45 _mm_loadu_si128((const __m128i *)_first_len_tbl);
46 const __m128i first_range_tbl =
47 _mm_loadu_si128((const __m128i *)_first_range_tbl);
48 const __m128i range_min_tbl =
49 _mm_loadu_si128((const __m128i *)_range_min_tbl);
50 const __m128i range_max_tbl =
51 _mm_loadu_si128((const __m128i *)_range_max_tbl);
52 const __m128i df_ee_tbl =
53 _mm_loadu_si128((const __m128i *)_df_ee_tbl);
54 const __m128i ef_fe_tbl =
55 _mm_loadu_si128((const __m128i *)_ef_fe_tbl);
56
57 __m128i error = _mm_set1_epi8(0);
58
59 while (len >= 32) {
60 /***************************** block 1 ****************************/
61 const __m128i input_a = _mm_loadu_si128((const __m128i *)data);
62
63 __m128i high_nibbles =
64 _mm_and_si128(_mm_srli_epi16(input_a, 4), _mm_set1_epi8(0x0F));
65
66 __m128i first_len_a = _mm_shuffle_epi8(first_len_tbl, high_nibbles);
67
68 __m128i range_a = _mm_shuffle_epi8(first_range_tbl, high_nibbles);
69
70 range_a = _mm_or_si128(
71 range_a, _mm_alignr_epi8(first_len_a, prev_first_len, 15));
72
73 __m128i tmp;
74 tmp = _mm_alignr_epi8(first_len_a, prev_first_len, 14);
75 tmp = _mm_subs_epu8(tmp, _mm_set1_epi8(1));
76 range_a = _mm_or_si128(range_a, tmp);
77
78 tmp = _mm_alignr_epi8(first_len_a, prev_first_len, 13);
79 tmp = _mm_subs_epu8(tmp, _mm_set1_epi8(2));
80 range_a = _mm_or_si128(range_a, tmp);
81
82 __m128i shift1, pos, range2;
83 shift1 = _mm_alignr_epi8(input_a, prev_input, 15);
84 pos = _mm_sub_epi8(shift1, _mm_set1_epi8(0xEF));
85 tmp = _mm_subs_epu8(pos, _mm_set1_epi8(0xF0));
86 range2 = _mm_shuffle_epi8(df_ee_tbl, tmp);
87 tmp = _mm_adds_epu8(pos, _mm_set1_epi8(0x70));
88 range2 = _mm_add_epi8(range2, _mm_shuffle_epi8(ef_fe_tbl, tmp));
89
90 range_a = _mm_add_epi8(range_a, range2);
91
92 __m128i minv = _mm_shuffle_epi8(range_min_tbl, range_a);
93 __m128i maxv = _mm_shuffle_epi8(range_max_tbl, range_a);
94
95 tmp = _mm_or_si128(
96 _mm_cmplt_epi8(input_a, minv),
97 _mm_cmpgt_epi8(input_a, maxv)
98 );
99 error = _mm_or_si128(error, tmp);
100
101 /***************************** block 2 ****************************/
102 const __m128i input_b = _mm_loadu_si128((const __m128i *)(data+16));
103
104 high_nibbles =
105 _mm_and_si128(_mm_srli_epi16(input_b, 4), _mm_set1_epi8(0x0F));
106
107 __m128i first_len_b = _mm_shuffle_epi8(first_len_tbl, high_nibbles);
108
109 __m128i range_b = _mm_shuffle_epi8(first_range_tbl, high_nibbles);
110
111 range_b = _mm_or_si128(
112 range_b, _mm_alignr_epi8(first_len_b, first_len_a, 15));
113
114
115 tmp = _mm_alignr_epi8(first_len_b, first_len_a, 14);
116 tmp = _mm_subs_epu8(tmp, _mm_set1_epi8(1));
117 range_b = _mm_or_si128(range_b, tmp);
118
119 tmp = _mm_alignr_epi8(first_len_b, first_len_a, 13);
120 tmp = _mm_subs_epu8(tmp, _mm_set1_epi8(2));
121 range_b = _mm_or_si128(range_b, tmp);
122
123 shift1 = _mm_alignr_epi8(input_b, input_a, 15);
124 pos = _mm_sub_epi8(shift1, _mm_set1_epi8(0xEF));
125 tmp = _mm_subs_epu8(pos, _mm_set1_epi8(0xF0));
126 range2 = _mm_shuffle_epi8(df_ee_tbl, tmp);
127 tmp = _mm_adds_epu8(pos, _mm_set1_epi8(0x70));
128 range2 = _mm_add_epi8(range2, _mm_shuffle_epi8(ef_fe_tbl, tmp));
129
130 range_b = _mm_add_epi8(range_b, range2);
131
132 minv = _mm_shuffle_epi8(range_min_tbl, range_b);
133 maxv = _mm_shuffle_epi8(range_max_tbl, range_b);
134
135
136 tmp = _mm_or_si128(
137 _mm_cmplt_epi8(input_b, minv),
138 _mm_cmpgt_epi8(input_b, maxv)
139 );
140 error = _mm_or_si128(error, tmp);
141
142 /************************ next iteration **************************/
143 prev_input = input_b;
144 prev_first_len = first_len_b;
145
146 data += 32;
147 len -= 32;
148 }
149
150 if (!_mm_testz_si128(error, error))
151 return -1;
152
153 int32_t token4 = _mm_extract_epi32(prev_input, 3);
154 const int8_t *token = (const int8_t *)&token4;
155 int lookahead = 0;
156 if (token[3] > (int8_t)0xBF)
157 lookahead = 1;
158 else if (token[2] > (int8_t)0xBF)
159 lookahead = 2;
160 else if (token[1] > (int8_t)0xBF)
161 lookahead = 3;
162
163 data -= lookahead;
164 len += lookahead;
165 }
166
167 return utf8_naive(data, len);
168 }
169
170 #endif
171