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1 /* Copyright 2013 Google Inc. All Rights Reserved.
2 
3    Distributed under MIT license.
4    See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
5 */
6 
7 #include "static_dict.h"
8 
9 #include "../common/dictionary.h"
10 #include "../common/platform.h"
11 #include "../common/transform.h"
12 #include "encoder_dict.h"
13 #include "find_match_length.h"
14 
15 #if defined(__cplusplus) || defined(c_plusplus)
16 extern "C" {
17 #endif
18 
Hash(const uint8_t * data)19 static BROTLI_INLINE uint32_t Hash(const uint8_t* data) {
20   uint32_t h = BROTLI_UNALIGNED_LOAD32LE(data) * kDictHashMul32;
21   /* The higher bits contain more mixture from the multiplication,
22      so we take our results from there. */
23   return h >> (32 - kDictNumBits);
24 }
25 
AddMatch(size_t distance,size_t len,size_t len_code,uint32_t * matches)26 static BROTLI_INLINE void AddMatch(size_t distance, size_t len, size_t len_code,
27                                    uint32_t* matches) {
28   uint32_t match = (uint32_t)((distance << 5) + len_code);
29   matches[len] = BROTLI_MIN(uint32_t, matches[len], match);
30 }
31 
DictMatchLength(const BrotliDictionary * dictionary,const uint8_t * data,size_t id,size_t len,size_t maxlen)32 static BROTLI_INLINE size_t DictMatchLength(const BrotliDictionary* dictionary,
33                                             const uint8_t* data,
34                                             size_t id,
35                                             size_t len,
36                                             size_t maxlen) {
37   const size_t offset = dictionary->offsets_by_length[len] + len * id;
38   return FindMatchLengthWithLimit(&dictionary->data[offset], data,
39                                   BROTLI_MIN(size_t, len, maxlen));
40 }
41 
IsMatch(const BrotliDictionary * dictionary,DictWord w,const uint8_t * data,size_t max_length)42 static BROTLI_INLINE BROTLI_BOOL IsMatch(const BrotliDictionary* dictionary,
43     DictWord w, const uint8_t* data, size_t max_length) {
44   if (w.len > max_length) {
45     return BROTLI_FALSE;
46   } else {
47     const size_t offset = dictionary->offsets_by_length[w.len] +
48         (size_t)w.len * (size_t)w.idx;
49     const uint8_t* dict = &dictionary->data[offset];
50     if (w.transform == 0) {
51       /* Match against base dictionary word. */
52       return
53           TO_BROTLI_BOOL(FindMatchLengthWithLimit(dict, data, w.len) == w.len);
54     } else if (w.transform == 10) {
55       /* Match against uppercase first transform.
56          Note that there are only ASCII uppercase words in the lookup table. */
57       return TO_BROTLI_BOOL(dict[0] >= 'a' && dict[0] <= 'z' &&
58               (dict[0] ^ 32) == data[0] &&
59               FindMatchLengthWithLimit(&dict[1], &data[1], w.len - 1u) ==
60               w.len - 1u);
61     } else {
62       /* Match against uppercase all transform.
63          Note that there are only ASCII uppercase words in the lookup table. */
64       size_t i;
65       for (i = 0; i < w.len; ++i) {
66         if (dict[i] >= 'a' && dict[i] <= 'z') {
67           if ((dict[i] ^ 32) != data[i]) return BROTLI_FALSE;
68         } else {
69           if (dict[i] != data[i]) return BROTLI_FALSE;
70         }
71       }
72       return BROTLI_TRUE;
73     }
74   }
75 }
76 
77 /* Finds matches for a single static dictionary */
BrotliFindAllStaticDictionaryMatchesFor(const BrotliEncoderDictionary * dictionary,const uint8_t * data,size_t min_length,size_t max_length,uint32_t * matches)78 static BROTLI_BOOL BrotliFindAllStaticDictionaryMatchesFor(
79     const BrotliEncoderDictionary* dictionary, const uint8_t* data,
80     size_t min_length, size_t max_length, uint32_t* matches) {
81   BROTLI_BOOL has_found_match = BROTLI_FALSE;
82 #if defined(BROTLI_EXPERIMENTAL)
83   if (dictionary->has_words_heavy) {
84     const BrotliTrieNode* node = &dictionary->trie.root;
85     size_t l = 0;
86     while (node && l < max_length) {
87       uint8_t c;
88       if (l >= min_length && node->len_) {
89         AddMatch(node->idx_, l, node->len_, matches);
90         has_found_match = BROTLI_TRUE;
91       }
92       c = data[l++];
93       node = BrotliTrieSub(&dictionary->trie, node, c);
94     }
95     return has_found_match;
96   }
97 #endif  /* BROTLI_EXPERIMENTAL */
98   {
99     size_t offset = dictionary->buckets[Hash(data)];
100     BROTLI_BOOL end = !offset;
101     while (!end) {
102       DictWord w = dictionary->dict_words[offset++];
103       const size_t l = w.len & 0x1F;
104       const size_t n = (size_t)1 << dictionary->words->size_bits_by_length[l];
105       const size_t id = w.idx;
106       end = !!(w.len & 0x80);
107       w.len = (uint8_t)l;
108       if (w.transform == 0) {
109         const size_t matchlen =
110             DictMatchLength(dictionary->words, data, id, l, max_length);
111         const uint8_t* s;
112         size_t minlen;
113         size_t maxlen;
114         size_t len;
115         /* Transform "" + BROTLI_TRANSFORM_IDENTITY + "" */
116         if (matchlen == l) {
117           AddMatch(id, l, l, matches);
118           has_found_match = BROTLI_TRUE;
119         }
120         /* Transforms "" + BROTLI_TRANSFORM_OMIT_LAST_1 + "" and
121                       "" + BROTLI_TRANSFORM_OMIT_LAST_1 + "ing " */
122         if (matchlen >= l - 1) {
123           AddMatch(id + 12 * n, l - 1, l, matches);
124           if (l + 2 < max_length &&
125               data[l - 1] == 'i' && data[l] == 'n' && data[l + 1] == 'g' &&
126               data[l + 2] == ' ') {
127             AddMatch(id + 49 * n, l + 3, l, matches);
128           }
129           has_found_match = BROTLI_TRUE;
130         }
131         /* Transform "" + BROTLI_TRANSFORM_OMIT_LAST_# + "" (# = 2 .. 9) */
132         minlen = min_length;
133         if (l > 9) minlen = BROTLI_MAX(size_t, minlen, l - 9);
134         maxlen = BROTLI_MIN(size_t, matchlen, l - 2);
135         for (len = minlen; len <= maxlen; ++len) {
136           size_t cut = l - len;
137           size_t transform_id = (cut << 2) +
138               (size_t)((dictionary->cutoffTransforms >> (cut * 6)) & 0x3F);
139           AddMatch(id + transform_id * n, len, l, matches);
140           has_found_match = BROTLI_TRUE;
141         }
142         if (matchlen < l || l + 6 >= max_length) {
143           continue;
144         }
145         s = &data[l];
146         /* Transforms "" + BROTLI_TRANSFORM_IDENTITY + <suffix> */
147         if (s[0] == ' ') {
148           AddMatch(id + n, l + 1, l, matches);
149           if (s[1] == 'a') {
150             if (s[2] == ' ') {
151               AddMatch(id + 28 * n, l + 3, l, matches);
152             } else if (s[2] == 's') {
153               if (s[3] == ' ') AddMatch(id + 46 * n, l + 4, l, matches);
154             } else if (s[2] == 't') {
155               if (s[3] == ' ') AddMatch(id + 60 * n, l + 4, l, matches);
156             } else if (s[2] == 'n') {
157               if (s[3] == 'd' && s[4] == ' ') {
158                 AddMatch(id + 10 * n, l + 5, l, matches);
159               }
160             }
161           } else if (s[1] == 'b') {
162             if (s[2] == 'y' && s[3] == ' ') {
163               AddMatch(id + 38 * n, l + 4, l, matches);
164             }
165           } else if (s[1] == 'i') {
166             if (s[2] == 'n') {
167               if (s[3] == ' ') AddMatch(id + 16 * n, l + 4, l, matches);
168             } else if (s[2] == 's') {
169               if (s[3] == ' ') AddMatch(id + 47 * n, l + 4, l, matches);
170             }
171           } else if (s[1] == 'f') {
172             if (s[2] == 'o') {
173               if (s[3] == 'r' && s[4] == ' ') {
174                 AddMatch(id + 25 * n, l + 5, l, matches);
175               }
176             } else if (s[2] == 'r') {
177               if (s[3] == 'o' && s[4] == 'm' && s[5] == ' ') {
178                 AddMatch(id + 37 * n, l + 6, l, matches);
179               }
180             }
181           } else if (s[1] == 'o') {
182             if (s[2] == 'f') {
183               if (s[3] == ' ') AddMatch(id + 8 * n, l + 4, l, matches);
184             } else if (s[2] == 'n') {
185               if (s[3] == ' ') AddMatch(id + 45 * n, l + 4, l, matches);
186             }
187           } else if (s[1] == 'n') {
188             if (s[2] == 'o' && s[3] == 't' && s[4] == ' ') {
189               AddMatch(id + 80 * n, l + 5, l, matches);
190             }
191           } else if (s[1] == 't') {
192             if (s[2] == 'h') {
193               if (s[3] == 'e') {
194                 if (s[4] == ' ') AddMatch(id + 5 * n, l + 5, l, matches);
195               } else if (s[3] == 'a') {
196                 if (s[4] == 't' && s[5] == ' ') {
197                   AddMatch(id + 29 * n, l + 6, l, matches);
198                 }
199               }
200             } else if (s[2] == 'o') {
201               if (s[3] == ' ') AddMatch(id + 17 * n, l + 4, l, matches);
202             }
203           } else if (s[1] == 'w') {
204             if (s[2] == 'i' && s[3] == 't' && s[4] == 'h' && s[5] == ' ') {
205               AddMatch(id + 35 * n, l + 6, l, matches);
206             }
207           }
208         } else if (s[0] == '"') {
209           AddMatch(id + 19 * n, l + 1, l, matches);
210           if (s[1] == '>') {
211             AddMatch(id + 21 * n, l + 2, l, matches);
212           }
213         } else if (s[0] == '.') {
214           AddMatch(id + 20 * n, l + 1, l, matches);
215           if (s[1] == ' ') {
216             AddMatch(id + 31 * n, l + 2, l, matches);
217             if (s[2] == 'T' && s[3] == 'h') {
218               if (s[4] == 'e') {
219                 if (s[5] == ' ') AddMatch(id + 43 * n, l + 6, l, matches);
220               } else if (s[4] == 'i') {
221                 if (s[5] == 's' && s[6] == ' ') {
222                   AddMatch(id + 75 * n, l + 7, l, matches);
223                 }
224               }
225             }
226           }
227         } else if (s[0] == ',') {
228           AddMatch(id + 76 * n, l + 1, l, matches);
229           if (s[1] == ' ') {
230             AddMatch(id + 14 * n, l + 2, l, matches);
231           }
232         } else if (s[0] == '\n') {
233           AddMatch(id + 22 * n, l + 1, l, matches);
234           if (s[1] == '\t') {
235             AddMatch(id + 50 * n, l + 2, l, matches);
236           }
237         } else if (s[0] == ']') {
238           AddMatch(id + 24 * n, l + 1, l, matches);
239         } else if (s[0] == '\'') {
240           AddMatch(id + 36 * n, l + 1, l, matches);
241         } else if (s[0] == ':') {
242           AddMatch(id + 51 * n, l + 1, l, matches);
243         } else if (s[0] == '(') {
244           AddMatch(id + 57 * n, l + 1, l, matches);
245         } else if (s[0] == '=') {
246           if (s[1] == '"') {
247             AddMatch(id + 70 * n, l + 2, l, matches);
248           } else if (s[1] == '\'') {
249             AddMatch(id + 86 * n, l + 2, l, matches);
250           }
251         } else if (s[0] == 'a') {
252           if (s[1] == 'l' && s[2] == ' ') {
253             AddMatch(id + 84 * n, l + 3, l, matches);
254           }
255         } else if (s[0] == 'e') {
256           if (s[1] == 'd') {
257             if (s[2] == ' ') AddMatch(id + 53 * n, l + 3, l, matches);
258           } else if (s[1] == 'r') {
259             if (s[2] == ' ') AddMatch(id + 82 * n, l + 3, l, matches);
260           } else if (s[1] == 's') {
261             if (s[2] == 't' && s[3] == ' ') {
262               AddMatch(id + 95 * n, l + 4, l, matches);
263             }
264           }
265         } else if (s[0] == 'f') {
266           if (s[1] == 'u' && s[2] == 'l' && s[3] == ' ') {
267             AddMatch(id + 90 * n, l + 4, l, matches);
268           }
269         } else if (s[0] == 'i') {
270           if (s[1] == 'v') {
271             if (s[2] == 'e' && s[3] == ' ') {
272               AddMatch(id + 92 * n, l + 4, l, matches);
273             }
274           } else if (s[1] == 'z') {
275             if (s[2] == 'e' && s[3] == ' ') {
276               AddMatch(id + 100 * n, l + 4, l, matches);
277             }
278           }
279         } else if (s[0] == 'l') {
280           if (s[1] == 'e') {
281             if (s[2] == 's' && s[3] == 's' && s[4] == ' ') {
282               AddMatch(id + 93 * n, l + 5, l, matches);
283             }
284           } else if (s[1] == 'y') {
285             if (s[2] == ' ') AddMatch(id + 61 * n, l + 3, l, matches);
286           }
287         } else if (s[0] == 'o') {
288           if (s[1] == 'u' && s[2] == 's' && s[3] == ' ') {
289             AddMatch(id + 106 * n, l + 4, l, matches);
290           }
291         }
292       } else {
293         /* Set is_all_caps=0 for BROTLI_TRANSFORM_UPPERCASE_FIRST and
294                is_all_caps=1 otherwise (BROTLI_TRANSFORM_UPPERCASE_ALL)
295            transform. */
296         const BROTLI_BOOL is_all_caps =
297             TO_BROTLI_BOOL(w.transform != BROTLI_TRANSFORM_UPPERCASE_FIRST);
298         const uint8_t* s;
299         if (!IsMatch(dictionary->words, w, data, max_length)) {
300           continue;
301         }
302         /* Transform "" + kUppercase{First,All} + "" */
303         AddMatch(id + (is_all_caps ? 44 : 9) * n, l, l, matches);
304         has_found_match = BROTLI_TRUE;
305         if (l + 1 >= max_length) {
306           continue;
307         }
308         /* Transforms "" + kUppercase{First,All} + <suffix> */
309         s = &data[l];
310         if (s[0] == ' ') {
311           AddMatch(id + (is_all_caps ? 68 : 4) * n, l + 1, l, matches);
312         } else if (s[0] == '"') {
313           AddMatch(id + (is_all_caps ? 87 : 66) * n, l + 1, l, matches);
314           if (s[1] == '>') {
315             AddMatch(id + (is_all_caps ? 97 : 69) * n, l + 2, l, matches);
316           }
317         } else if (s[0] == '.') {
318           AddMatch(id + (is_all_caps ? 101 : 79) * n, l + 1, l, matches);
319           if (s[1] == ' ') {
320             AddMatch(id + (is_all_caps ? 114 : 88) * n, l + 2, l, matches);
321           }
322         } else if (s[0] == ',') {
323           AddMatch(id + (is_all_caps ? 112 : 99) * n, l + 1, l, matches);
324           if (s[1] == ' ') {
325             AddMatch(id + (is_all_caps ? 107 : 58) * n, l + 2, l, matches);
326           }
327         } else if (s[0] == '\'') {
328           AddMatch(id + (is_all_caps ? 94 : 74) * n, l + 1, l, matches);
329         } else if (s[0] == '(') {
330           AddMatch(id + (is_all_caps ? 113 : 78) * n, l + 1, l, matches);
331         } else if (s[0] == '=') {
332           if (s[1] == '"') {
333             AddMatch(id + (is_all_caps ? 105 : 104) * n, l + 2, l, matches);
334           } else if (s[1] == '\'') {
335             AddMatch(id + (is_all_caps ? 116 : 108) * n, l + 2, l, matches);
336           }
337         }
338       }
339     }
340   }
341   /* Transforms with prefixes " " and "." */
342   if (max_length >= 5 && (data[0] == ' ' || data[0] == '.')) {
343     BROTLI_BOOL is_space = TO_BROTLI_BOOL(data[0] == ' ');
344     size_t offset = dictionary->buckets[Hash(&data[1])];
345     BROTLI_BOOL end = !offset;
346     while (!end) {
347       DictWord w = dictionary->dict_words[offset++];
348       const size_t l = w.len & 0x1F;
349       const size_t n = (size_t)1 << dictionary->words->size_bits_by_length[l];
350       const size_t id = w.idx;
351       end = !!(w.len & 0x80);
352       w.len = (uint8_t)l;
353       if (w.transform == 0) {
354         const uint8_t* s;
355         if (!IsMatch(dictionary->words, w, &data[1], max_length - 1)) {
356           continue;
357         }
358         /* Transforms " " + BROTLI_TRANSFORM_IDENTITY + "" and
359                       "." + BROTLI_TRANSFORM_IDENTITY + "" */
360         AddMatch(id + (is_space ? 6 : 32) * n, l + 1, l, matches);
361         has_found_match = BROTLI_TRUE;
362         if (l + 2 >= max_length) {
363           continue;
364         }
365         /* Transforms " " + BROTLI_TRANSFORM_IDENTITY + <suffix> and
366                       "." + BROTLI_TRANSFORM_IDENTITY + <suffix>
367         */
368         s = &data[l + 1];
369         if (s[0] == ' ') {
370           AddMatch(id + (is_space ? 2 : 77) * n, l + 2, l, matches);
371         } else if (s[0] == '(') {
372           AddMatch(id + (is_space ? 89 : 67) * n, l + 2, l, matches);
373         } else if (is_space) {
374           if (s[0] == ',') {
375             AddMatch(id + 103 * n, l + 2, l, matches);
376             if (s[1] == ' ') {
377               AddMatch(id + 33 * n, l + 3, l, matches);
378             }
379           } else if (s[0] == '.') {
380             AddMatch(id + 71 * n, l + 2, l, matches);
381             if (s[1] == ' ') {
382               AddMatch(id + 52 * n, l + 3, l, matches);
383             }
384           } else if (s[0] == '=') {
385             if (s[1] == '"') {
386               AddMatch(id + 81 * n, l + 3, l, matches);
387             } else if (s[1] == '\'') {
388               AddMatch(id + 98 * n, l + 3, l, matches);
389             }
390           }
391         }
392       } else if (is_space) {
393         /* Set is_all_caps=0 for BROTLI_TRANSFORM_UPPERCASE_FIRST and
394                is_all_caps=1 otherwise (BROTLI_TRANSFORM_UPPERCASE_ALL)
395            transform. */
396         const BROTLI_BOOL is_all_caps =
397             TO_BROTLI_BOOL(w.transform != BROTLI_TRANSFORM_UPPERCASE_FIRST);
398         const uint8_t* s;
399         if (!IsMatch(dictionary->words, w, &data[1], max_length - 1)) {
400           continue;
401         }
402         /* Transforms " " + kUppercase{First,All} + "" */
403         AddMatch(id + (is_all_caps ? 85 : 30) * n, l + 1, l, matches);
404         has_found_match = BROTLI_TRUE;
405         if (l + 2 >= max_length) {
406           continue;
407         }
408         /* Transforms " " + kUppercase{First,All} + <suffix> */
409         s = &data[l + 1];
410         if (s[0] == ' ') {
411           AddMatch(id + (is_all_caps ? 83 : 15) * n, l + 2, l, matches);
412         } else if (s[0] == ',') {
413           if (!is_all_caps) {
414             AddMatch(id + 109 * n, l + 2, l, matches);
415           }
416           if (s[1] == ' ') {
417             AddMatch(id + (is_all_caps ? 111 : 65) * n, l + 3, l, matches);
418           }
419         } else if (s[0] == '.') {
420           AddMatch(id + (is_all_caps ? 115 : 96) * n, l + 2, l, matches);
421           if (s[1] == ' ') {
422             AddMatch(id + (is_all_caps ? 117 : 91) * n, l + 3, l, matches);
423           }
424         } else if (s[0] == '=') {
425           if (s[1] == '"') {
426             AddMatch(id + (is_all_caps ? 110 : 118) * n, l + 3, l, matches);
427           } else if (s[1] == '\'') {
428             AddMatch(id + (is_all_caps ? 119 : 120) * n, l + 3, l, matches);
429           }
430         }
431       }
432     }
433   }
434   if (max_length >= 6) {
435     /* Transforms with prefixes "e ", "s ", ", " and "\xC2\xA0" */
436     if ((data[1] == ' ' &&
437          (data[0] == 'e' || data[0] == 's' || data[0] == ',')) ||
438         (data[0] == 0xC2 && data[1] == 0xA0)) {
439       size_t offset = dictionary->buckets[Hash(&data[2])];
440       BROTLI_BOOL end = !offset;
441       while (!end) {
442         DictWord w = dictionary->dict_words[offset++];
443         const size_t l = w.len & 0x1F;
444         const size_t n = (size_t)1 << dictionary->words->size_bits_by_length[l];
445         const size_t id = w.idx;
446         end = !!(w.len & 0x80);
447         w.len = (uint8_t)l;
448         if (w.transform == 0 &&
449             IsMatch(dictionary->words, w, &data[2], max_length - 2)) {
450           if (data[0] == 0xC2) {
451             AddMatch(id + 102 * n, l + 2, l, matches);
452             has_found_match = BROTLI_TRUE;
453           } else if (l + 2 < max_length && data[l + 2] == ' ') {
454             size_t t = data[0] == 'e' ? 18 : (data[0] == 's' ? 7 : 13);
455             AddMatch(id + t * n, l + 3, l, matches);
456             has_found_match = BROTLI_TRUE;
457           }
458         }
459       }
460     }
461   }
462   if (max_length >= 9) {
463     /* Transforms with prefixes " the " and ".com/" */
464     if ((data[0] == ' ' && data[1] == 't' && data[2] == 'h' &&
465          data[3] == 'e' && data[4] == ' ') ||
466         (data[0] == '.' && data[1] == 'c' && data[2] == 'o' &&
467          data[3] == 'm' && data[4] == '/')) {
468       size_t offset = dictionary->buckets[Hash(&data[5])];
469       BROTLI_BOOL end = !offset;
470       while (!end) {
471         DictWord w = dictionary->dict_words[offset++];
472         const size_t l = w.len & 0x1F;
473         const size_t n = (size_t)1 << dictionary->words->size_bits_by_length[l];
474         const size_t id = w.idx;
475         end = !!(w.len & 0x80);
476         w.len = (uint8_t)l;
477         if (w.transform == 0 &&
478             IsMatch(dictionary->words, w, &data[5], max_length - 5)) {
479           AddMatch(id + (data[0] == ' ' ? 41 : 72) * n, l + 5, l, matches);
480           has_found_match = BROTLI_TRUE;
481           if (l + 5 < max_length) {
482             const uint8_t* s = &data[l + 5];
483             if (data[0] == ' ') {
484               if (l + 8 < max_length &&
485                   s[0] == ' ' && s[1] == 'o' && s[2] == 'f' && s[3] == ' ') {
486                 AddMatch(id + 62 * n, l + 9, l, matches);
487                 if (l + 12 < max_length &&
488                     s[4] == 't' && s[5] == 'h' && s[6] == 'e' && s[7] == ' ') {
489                   AddMatch(id + 73 * n, l + 13, l, matches);
490                 }
491               }
492             }
493           }
494         }
495       }
496     }
497   }
498   return has_found_match;
499 }
500 
501 /* Finds matches for one or more dictionaries, if multiple are present
502    in the contextual dictionary */
BrotliFindAllStaticDictionaryMatches(const BrotliEncoderDictionary * dictionary,const uint8_t * data,size_t min_length,size_t max_length,uint32_t * matches)503 BROTLI_BOOL BrotliFindAllStaticDictionaryMatches(
504     const BrotliEncoderDictionary* dictionary, const uint8_t* data,
505     size_t min_length, size_t max_length, uint32_t* matches) {
506   BROTLI_BOOL has_found_match =
507       BrotliFindAllStaticDictionaryMatchesFor(
508           dictionary, data, min_length, max_length, matches);
509 
510   if (!!dictionary->parent && dictionary->parent->num_dictionaries > 1) {
511     uint32_t matches2[BROTLI_MAX_STATIC_DICTIONARY_MATCH_LEN + 1];
512     int l;
513     const BrotliEncoderDictionary* dictionary2 = dictionary->parent->dict[0];
514     if (dictionary2 == dictionary) {
515       dictionary2 = dictionary->parent->dict[1];
516     }
517 
518     for (l = 0; l < BROTLI_MAX_STATIC_DICTIONARY_MATCH_LEN + 1; l++) {
519       matches2[l] = kInvalidMatch;
520     }
521 
522     has_found_match |= BrotliFindAllStaticDictionaryMatchesFor(
523         dictionary2, data, min_length, max_length, matches2);
524 
525     for (l = 0; l < BROTLI_MAX_STATIC_DICTIONARY_MATCH_LEN + 1; l++) {
526       if (matches2[l] != kInvalidMatch) {
527         uint32_t dist = (uint32_t)(matches2[l] >> 5);
528         uint32_t len_code = matches2[l] & 31;
529         uint32_t skipdist = (uint32_t)((uint32_t)(1 << dictionary->words->
530             size_bits_by_length[len_code]) & ~1u) *
531             (uint32_t)dictionary->num_transforms;
532         /* TODO(lode): check for dist overflow */
533         dist += skipdist;
534         AddMatch(dist, (size_t)l, len_code, matches);
535       }
536     }
537   }
538   return has_found_match;
539 }
540 #if defined(__cplusplus) || defined(c_plusplus)
541 }  /* extern "C" */
542 #endif
543