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1/**
2 * Copyright (c) 2016-present, Przemyslaw Skibinski, Yann Collet, Facebook, Inc.
3 * All rights reserved.
4 *
5 * This source code is licensed under the BSD-style license found in the
6 * LICENSE file in the root directory of https://github.com/facebook/zstd.
7 * An additional grant of patent rights can be found in the PATENTS file in the
8 * same directory.
9 *
10 * This program is free software; you can redistribute it and/or modify it under
11 * the terms of the GNU General Public License version 2 as published by the
12 * Free Software Foundation. This program is dual-licensed; you may select
13 * either version 2 of the GNU General Public License ("GPL") or BSD license
14 * ("BSD").
15 */
16
17/* Note : this file is intended to be included within zstd_compress.c */
18
19#ifndef ZSTD_OPT_H_91842398743
20#define ZSTD_OPT_H_91842398743
21
22#define ZSTD_LITFREQ_ADD 2
23#define ZSTD_FREQ_DIV 4
24#define ZSTD_MAX_PRICE (1 << 30)
25
26/*-*************************************
27* Price functions for optimal parser
28***************************************/
29FORCE_INLINE void ZSTD_setLog2Prices(seqStore_t *ssPtr)
30{
31 ssPtr->log2matchLengthSum = ZSTD_highbit32(ssPtr->matchLengthSum + 1);
32 ssPtr->log2litLengthSum = ZSTD_highbit32(ssPtr->litLengthSum + 1);
33 ssPtr->log2litSum = ZSTD_highbit32(ssPtr->litSum + 1);
34 ssPtr->log2offCodeSum = ZSTD_highbit32(ssPtr->offCodeSum + 1);
35 ssPtr->factor = 1 + ((ssPtr->litSum >> 5) / ssPtr->litLengthSum) + ((ssPtr->litSum << 1) / (ssPtr->litSum + ssPtr->matchSum));
36}
37
38ZSTD_STATIC void ZSTD_rescaleFreqs(seqStore_t *ssPtr, const BYTE *src, size_t srcSize)
39{
40 unsigned u;
41
42 ssPtr->cachedLiterals = NULL;
43 ssPtr->cachedPrice = ssPtr->cachedLitLength = 0;
44 ssPtr->staticPrices = 0;
45
46 if (ssPtr->litLengthSum == 0) {
47 if (srcSize <= 1024)
48 ssPtr->staticPrices = 1;
49
50 for (u = 0; u <= MaxLit; u++)
51 ssPtr->litFreq[u] = 0;
52 for (u = 0; u < srcSize; u++)
53 ssPtr->litFreq[src[u]]++;
54
55 ssPtr->litSum = 0;
56 ssPtr->litLengthSum = MaxLL + 1;
57 ssPtr->matchLengthSum = MaxML + 1;
58 ssPtr->offCodeSum = (MaxOff + 1);
59 ssPtr->matchSum = (ZSTD_LITFREQ_ADD << Litbits);
60
61 for (u = 0; u <= MaxLit; u++) {
62 ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> ZSTD_FREQ_DIV);
63 ssPtr->litSum += ssPtr->litFreq[u];
64 }
65 for (u = 0; u <= MaxLL; u++)
66 ssPtr->litLengthFreq[u] = 1;
67 for (u = 0; u <= MaxML; u++)
68 ssPtr->matchLengthFreq[u] = 1;
69 for (u = 0; u <= MaxOff; u++)
70 ssPtr->offCodeFreq[u] = 1;
71 } else {
72 ssPtr->matchLengthSum = 0;
73 ssPtr->litLengthSum = 0;
74 ssPtr->offCodeSum = 0;
75 ssPtr->matchSum = 0;
76 ssPtr->litSum = 0;
77
78 for (u = 0; u <= MaxLit; u++) {
79 ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> (ZSTD_FREQ_DIV + 1));
80 ssPtr->litSum += ssPtr->litFreq[u];
81 }
82 for (u = 0; u <= MaxLL; u++) {
83 ssPtr->litLengthFreq[u] = 1 + (ssPtr->litLengthFreq[u] >> (ZSTD_FREQ_DIV + 1));
84 ssPtr->litLengthSum += ssPtr->litLengthFreq[u];
85 }
86 for (u = 0; u <= MaxML; u++) {
87 ssPtr->matchLengthFreq[u] = 1 + (ssPtr->matchLengthFreq[u] >> ZSTD_FREQ_DIV);
88 ssPtr->matchLengthSum += ssPtr->matchLengthFreq[u];
89 ssPtr->matchSum += ssPtr->matchLengthFreq[u] * (u + 3);
90 }
91 ssPtr->matchSum *= ZSTD_LITFREQ_ADD;
92 for (u = 0; u <= MaxOff; u++) {
93 ssPtr->offCodeFreq[u] = 1 + (ssPtr->offCodeFreq[u] >> ZSTD_FREQ_DIV);
94 ssPtr->offCodeSum += ssPtr->offCodeFreq[u];
95 }
96 }
97
98 ZSTD_setLog2Prices(ssPtr);
99}
100
101FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t *ssPtr, U32 litLength, const BYTE *literals)
102{
103 U32 price, u;
104
105 if (ssPtr->staticPrices)
106 return ZSTD_highbit32((U32)litLength + 1) + (litLength * 6);
107
108 if (litLength == 0)
109 return ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[0] + 1);
110
111 /* literals */
112 if (ssPtr->cachedLiterals == literals) {
113 U32 const additional = litLength - ssPtr->cachedLitLength;
114 const BYTE *literals2 = ssPtr->cachedLiterals + ssPtr->cachedLitLength;
115 price = ssPtr->cachedPrice + additional * ssPtr->log2litSum;
116 for (u = 0; u < additional; u++)
117 price -= ZSTD_highbit32(ssPtr->litFreq[literals2[u]] + 1);
118 ssPtr->cachedPrice = price;
119 ssPtr->cachedLitLength = litLength;
120 } else {
121 price = litLength * ssPtr->log2litSum;
122 for (u = 0; u < litLength; u++)
123 price -= ZSTD_highbit32(ssPtr->litFreq[literals[u]] + 1);
124
125 if (litLength >= 12) {
126 ssPtr->cachedLiterals = literals;
127 ssPtr->cachedPrice = price;
128 ssPtr->cachedLitLength = litLength;
129 }
130 }
131
132 /* literal Length */
133 {
134 const BYTE LL_deltaCode = 19;
135 const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength];
136 price += LL_bits[llCode] + ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[llCode] + 1);
137 }
138
139 return price;
140}
141
142FORCE_INLINE U32 ZSTD_getPrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength, const int ultra)
143{
144 /* offset */
145 U32 price;
146 BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1);
147
148 if (seqStorePtr->staticPrices)
149 return ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit32((U32)matchLength + 1) + 16 + offCode;
150
151 price = offCode + seqStorePtr->log2offCodeSum - ZSTD_highbit32(seqStorePtr->offCodeFreq[offCode] + 1);
152 if (!ultra && offCode >= 20)
153 price += (offCode - 19) * 2;
154
155 /* match Length */
156 {
157 const BYTE ML_deltaCode = 36;
158 const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength];
159 price += ML_bits[mlCode] + seqStorePtr->log2matchLengthSum - ZSTD_highbit32(seqStorePtr->matchLengthFreq[mlCode] + 1);
160 }
161
162 return price + ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + seqStorePtr->factor;
163}
164
165ZSTD_STATIC void ZSTD_updatePrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength)
166{
167 U32 u;
168
169 /* literals */
170 seqStorePtr->litSum += litLength * ZSTD_LITFREQ_ADD;
171 for (u = 0; u < litLength; u++)
172 seqStorePtr->litFreq[literals[u]] += ZSTD_LITFREQ_ADD;
173
174 /* literal Length */
175 {
176 const BYTE LL_deltaCode = 19;
177 const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength];
178 seqStorePtr->litLengthFreq[llCode]++;
179 seqStorePtr->litLengthSum++;
180 }
181
182 /* match offset */
183 {
184 BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1);
185 seqStorePtr->offCodeSum++;
186 seqStorePtr->offCodeFreq[offCode]++;
187 }
188
189 /* match Length */
190 {
191 const BYTE ML_deltaCode = 36;
192 const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength];
193 seqStorePtr->matchLengthFreq[mlCode]++;
194 seqStorePtr->matchLengthSum++;
195 }
196
197 ZSTD_setLog2Prices(seqStorePtr);
198}
199
200#define SET_PRICE(pos, mlen_, offset_, litlen_, price_) \
201 { \
202 while (last_pos < pos) { \
203 opt[last_pos + 1].price = ZSTD_MAX_PRICE; \
204 last_pos++; \
205 } \
206 opt[pos].mlen = mlen_; \
207 opt[pos].off = offset_; \
208 opt[pos].litlen = litlen_; \
209 opt[pos].price = price_; \
210 }
211
212/* Update hashTable3 up to ip (excluded)
213 Assumption : always within prefix (i.e. not within extDict) */
214FORCE_INLINE
215U32 ZSTD_insertAndFindFirstIndexHash3(ZSTD_CCtx *zc, const BYTE *ip)
216{
217 U32 *const hashTable3 = zc->hashTable3;
218 U32 const hashLog3 = zc->hashLog3;
219 const BYTE *const base = zc->base;
220 U32 idx = zc->nextToUpdate3;
221 const U32 target = zc->nextToUpdate3 = (U32)(ip - base);
222 const size_t hash3 = ZSTD_hash3Ptr(ip, hashLog3);
223
224 while (idx < target) {
225 hashTable3[ZSTD_hash3Ptr(base + idx, hashLog3)] = idx;
226 idx++;
227 }
228
229 return hashTable3[hash3];
230}
231
232/*-*************************************
233* Binary Tree search
234***************************************/
235static U32 ZSTD_insertBtAndGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, U32 nbCompares, const U32 mls, U32 extDict,
236 ZSTD_match_t *matches, const U32 minMatchLen)
237{
238 const BYTE *const base = zc->base;
239 const U32 curr = (U32)(ip - base);
240 const U32 hashLog = zc->params.cParams.hashLog;
241 const size_t h = ZSTD_hashPtr(ip, hashLog, mls);
242 U32 *const hashTable = zc->hashTable;
243 U32 matchIndex = hashTable[h];
244 U32 *const bt = zc->chainTable;
245 const U32 btLog = zc->params.cParams.chainLog - 1;
246 const U32 btMask = (1U << btLog) - 1;
247 size_t commonLengthSmaller = 0, commonLengthLarger = 0;
248 const BYTE *const dictBase = zc->dictBase;
249 const U32 dictLimit = zc->dictLimit;
250 const BYTE *const dictEnd = dictBase + dictLimit;
251 const BYTE *const prefixStart = base + dictLimit;
252 const U32 btLow = btMask >= curr ? 0 : curr - btMask;
253 const U32 windowLow = zc->lowLimit;
254 U32 *smallerPtr = bt + 2 * (curr & btMask);
255 U32 *largerPtr = bt + 2 * (curr & btMask) + 1;
256 U32 matchEndIdx = curr + 8;
257 U32 dummy32; /* to be nullified at the end */
258 U32 mnum = 0;
259
260 const U32 minMatch = (mls == 3) ? 3 : 4;
261 size_t bestLength = minMatchLen - 1;
262
263 if (minMatch == 3) { /* HC3 match finder */
264 U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3(zc, ip);
265 if (matchIndex3 > windowLow && (curr - matchIndex3 < (1 << 18))) {
266 const BYTE *match;
267 size_t currMl = 0;
268 if ((!extDict) || matchIndex3 >= dictLimit) {
269 match = base + matchIndex3;
270 if (match[bestLength] == ip[bestLength])
271 currMl = ZSTD_count(ip, match, iLimit);
272 } else {
273 match = dictBase + matchIndex3;
274 if (ZSTD_readMINMATCH(match, MINMATCH) ==
275 ZSTD_readMINMATCH(ip, MINMATCH)) /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
276 currMl = ZSTD_count_2segments(ip + MINMATCH, match + MINMATCH, iLimit, dictEnd, prefixStart) + MINMATCH;
277 }
278
279 /* save best solution */
280 if (currMl > bestLength) {
281 bestLength = currMl;
282 matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex3;
283 matches[mnum].len = (U32)currMl;
284 mnum++;
285 if (currMl > ZSTD_OPT_NUM)
286 goto update;
287 if (ip + currMl == iLimit)
288 goto update; /* best possible, and avoid read overflow*/
289 }
290 }
291 }
292
293 hashTable[h] = curr; /* Update Hash Table */
294
295 while (nbCompares-- && (matchIndex > windowLow)) {
296 U32 *nextPtr = bt + 2 * (matchIndex & btMask);
297 size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
298 const BYTE *match;
299
300 if ((!extDict) || (matchIndex + matchLength >= dictLimit)) {
301 match = base + matchIndex;
302 if (match[matchLength] == ip[matchLength]) {
303 matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iLimit) + 1;
304 }
305 } else {
306 match = dictBase + matchIndex;
307 matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iLimit, dictEnd, prefixStart);
308 if (matchIndex + matchLength >= dictLimit)
309 match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
310 }
311
312 if (matchLength > bestLength) {
313 if (matchLength > matchEndIdx - matchIndex)
314 matchEndIdx = matchIndex + (U32)matchLength;
315 bestLength = matchLength;
316 matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex;
317 matches[mnum].len = (U32)matchLength;
318 mnum++;
319 if (matchLength > ZSTD_OPT_NUM)
320 break;
321 if (ip + matchLength == iLimit) /* equal : no way to know if inf or sup */
322 break; /* drop, to guarantee consistency (miss a little bit of compression) */
323 }
324
325 if (match[matchLength] < ip[matchLength]) {
326 /* match is smaller than curr */
327 *smallerPtr = matchIndex; /* update smaller idx */
328 commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
329 if (matchIndex <= btLow) {
330 smallerPtr = &dummy32;
331 break;
332 } /* beyond tree size, stop the search */
333 smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */
334 matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */
335 } else {
336 /* match is larger than curr */
337 *largerPtr = matchIndex;
338 commonLengthLarger = matchLength;
339 if (matchIndex <= btLow) {
340 largerPtr = &dummy32;
341 break;
342 } /* beyond tree size, stop the search */
343 largerPtr = nextPtr;
344 matchIndex = nextPtr[0];
345 }
346 }
347
348 *smallerPtr = *largerPtr = 0;
349
350update:
351 zc->nextToUpdate = (matchEndIdx > curr + 8) ? matchEndIdx - 8 : curr + 1;
352 return mnum;
353}
354
355/** Tree updater, providing best match */
356static U32 ZSTD_BtGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls, ZSTD_match_t *matches,
357 const U32 minMatchLen)
358{
359 if (ip < zc->base + zc->nextToUpdate)
360 return 0; /* skipped area */
361 ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls);
362 return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 0, matches, minMatchLen);
363}
364
365static U32 ZSTD_BtGetAllMatches_selectMLS(ZSTD_CCtx *zc, /* Index table will be updated */
366 const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch,
367 ZSTD_match_t *matches, const U32 minMatchLen)
368{
369 switch (matchLengthSearch) {
370 case 3: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen);
371 default:
372 case 4: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen);
373 case 5: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen);
374 case 7:
375 case 6: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen);
376 }
377}
378
379/** Tree updater, providing best match */
380static U32 ZSTD_BtGetAllMatches_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls,
381 ZSTD_match_t *matches, const U32 minMatchLen)
382{
383 if (ip < zc->base + zc->nextToUpdate)
384 return 0; /* skipped area */
385 ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls);
386 return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 1, matches, minMatchLen);
387}
388
389static U32 ZSTD_BtGetAllMatches_selectMLS_extDict(ZSTD_CCtx *zc, /* Index table will be updated */
390 const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch,
391 ZSTD_match_t *matches, const U32 minMatchLen)
392{
393 switch (matchLengthSearch) {
394 case 3: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen);
395 default:
396 case 4: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen);
397 case 5: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen);
398 case 7:
399 case 6: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen);
400 }
401}
402
403/*-*******************************
404* Optimal parser
405*********************************/
406FORCE_INLINE
407void ZSTD_compressBlock_opt_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra)
408{
409 seqStore_t *seqStorePtr = &(ctx->seqStore);
410 const BYTE *const istart = (const BYTE *)src;
411 const BYTE *ip = istart;
412 const BYTE *anchor = istart;
413 const BYTE *const iend = istart + srcSize;
414 const BYTE *const ilimit = iend - 8;
415 const BYTE *const base = ctx->base;
416 const BYTE *const prefixStart = base + ctx->dictLimit;
417
418 const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
419 const U32 sufficient_len = ctx->params.cParams.targetLength;
420 const U32 mls = ctx->params.cParams.searchLength;
421 const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
422
423 ZSTD_optimal_t *opt = seqStorePtr->priceTable;
424 ZSTD_match_t *matches = seqStorePtr->matchTable;
425 const BYTE *inr;
426 U32 offset, rep[ZSTD_REP_NUM];
427
428 /* init */
429 ctx->nextToUpdate3 = ctx->nextToUpdate;
430 ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize);
431 ip += (ip == prefixStart);
432 {
433 U32 i;
434 for (i = 0; i < ZSTD_REP_NUM; i++)
435 rep[i] = ctx->rep[i];
436 }
437
438 /* Match Loop */
439 while (ip < ilimit) {
440 U32 cur, match_num, last_pos, litlen, price;
441 U32 u, mlen, best_mlen, best_off, litLength;
442 memset(opt, 0, sizeof(ZSTD_optimal_t));
443 last_pos = 0;
444 litlen = (U32)(ip - anchor);
445
446 /* check repCode */
447 {
448 U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor);
449 for (i = (ip == anchor); i < last_i; i++) {
450 const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
451 if ((repCur > 0) && (repCur < (S32)(ip - prefixStart)) &&
452 (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repCur, minMatch))) {
453 mlen = (U32)ZSTD_count(ip + minMatch, ip + minMatch - repCur, iend) + minMatch;
454 if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
455 best_mlen = mlen;
456 best_off = i;
457 cur = 0;
458 last_pos = 1;
459 goto _storeSequence;
460 }
461 best_off = i - (ip == anchor);
462 do {
463 price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
464 if (mlen > last_pos || price < opt[mlen].price)
465 SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
466 mlen--;
467 } while (mlen >= minMatch);
468 }
469 }
470 }
471
472 match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, ip, iend, maxSearches, mls, matches, minMatch);
473
474 if (!last_pos && !match_num) {
475 ip++;
476 continue;
477 }
478
479 if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
480 best_mlen = matches[match_num - 1].len;
481 best_off = matches[match_num - 1].off;
482 cur = 0;
483 last_pos = 1;
484 goto _storeSequence;
485 }
486
487 /* set prices using matches at position = 0 */
488 best_mlen = (last_pos) ? last_pos : minMatch;
489 for (u = 0; u < match_num; u++) {
490 mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
491 best_mlen = matches[u].len;
492 while (mlen <= best_mlen) {
493 price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
494 if (mlen > last_pos || price < opt[mlen].price)
495 SET_PRICE(mlen, mlen, matches[u].off, litlen, price); /* note : macro modifies last_pos */
496 mlen++;
497 }
498 }
499
500 if (last_pos < minMatch) {
501 ip++;
502 continue;
503 }
504
505 /* initialize opt[0] */
506 {
507 U32 i;
508 for (i = 0; i < ZSTD_REP_NUM; i++)
509 opt[0].rep[i] = rep[i];
510 }
511 opt[0].mlen = 1;
512 opt[0].litlen = litlen;
513
514 /* check further positions */
515 for (cur = 1; cur <= last_pos; cur++) {
516 inr = ip + cur;
517
518 if (opt[cur - 1].mlen == 1) {
519 litlen = opt[cur - 1].litlen + 1;
520 if (cur > litlen) {
521 price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen);
522 } else
523 price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
524 } else {
525 litlen = 1;
526 price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1);
527 }
528
529 if (cur > last_pos || price <= opt[cur].price)
530 SET_PRICE(cur, 1, 0, litlen, price);
531
532 if (cur == last_pos)
533 break;
534
535 if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */
536 continue;
537
538 mlen = opt[cur].mlen;
539 if (opt[cur].off > ZSTD_REP_MOVE_OPT) {
540 opt[cur].rep[2] = opt[cur - mlen].rep[1];
541 opt[cur].rep[1] = opt[cur - mlen].rep[0];
542 opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT;
543 } else {
544 opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2];
545 opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1];
546 opt[cur].rep[0] =
547 ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]);
548 }
549
550 best_mlen = minMatch;
551 {
552 U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1);
553 for (i = (opt[cur].mlen != 1); i < last_i; i++) { /* check rep */
554 const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
555 if ((repCur > 0) && (repCur < (S32)(inr - prefixStart)) &&
556 (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(inr - repCur, minMatch))) {
557 mlen = (U32)ZSTD_count(inr + minMatch, inr + minMatch - repCur, iend) + minMatch;
558
559 if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
560 best_mlen = mlen;
561 best_off = i;
562 last_pos = cur + 1;
563 goto _storeSequence;
564 }
565
566 best_off = i - (opt[cur].mlen != 1);
567 if (mlen > best_mlen)
568 best_mlen = mlen;
569
570 do {
571 if (opt[cur].mlen == 1) {
572 litlen = opt[cur].litlen;
573 if (cur > litlen) {
574 price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen,
575 best_off, mlen - MINMATCH, ultra);
576 } else
577 price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
578 } else {
579 litlen = 0;
580 price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra);
581 }
582
583 if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
584 SET_PRICE(cur + mlen, mlen, i, litlen, price);
585 mlen--;
586 } while (mlen >= minMatch);
587 }
588 }
589 }
590
591 match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, inr, iend, maxSearches, mls, matches, best_mlen);
592
593 if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
594 best_mlen = matches[match_num - 1].len;
595 best_off = matches[match_num - 1].off;
596 last_pos = cur + 1;
597 goto _storeSequence;
598 }
599
600 /* set prices using matches at position = cur */
601 for (u = 0; u < match_num; u++) {
602 mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
603 best_mlen = matches[u].len;
604
605 while (mlen <= best_mlen) {
606 if (opt[cur].mlen == 1) {
607 litlen = opt[cur].litlen;
608 if (cur > litlen)
609 price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen,
610 matches[u].off - 1, mlen - MINMATCH, ultra);
611 else
612 price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
613 } else {
614 litlen = 0;
615 price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra);
616 }
617
618 if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
619 SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
620
621 mlen++;
622 }
623 }
624 }
625
626 best_mlen = opt[last_pos].mlen;
627 best_off = opt[last_pos].off;
628 cur = last_pos - best_mlen;
629
630 /* store sequence */
631_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */
632 opt[0].mlen = 1;
633
634 while (1) {
635 mlen = opt[cur].mlen;
636 offset = opt[cur].off;
637 opt[cur].mlen = best_mlen;
638 opt[cur].off = best_off;
639 best_mlen = mlen;
640 best_off = offset;
641 if (mlen > cur)
642 break;
643 cur -= mlen;
644 }
645
646 for (u = 0; u <= last_pos;) {
647 u += opt[u].mlen;
648 }
649
650 for (cur = 0; cur < last_pos;) {
651 mlen = opt[cur].mlen;
652 if (mlen == 1) {
653 ip++;
654 cur++;
655 continue;
656 }
657 offset = opt[cur].off;
658 cur += mlen;
659 litLength = (U32)(ip - anchor);
660
661 if (offset > ZSTD_REP_MOVE_OPT) {
662 rep[2] = rep[1];
663 rep[1] = rep[0];
664 rep[0] = offset - ZSTD_REP_MOVE_OPT;
665 offset--;
666 } else {
667 if (offset != 0) {
668 best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]);
669 if (offset != 1)
670 rep[2] = rep[1];
671 rep[1] = rep[0];
672 rep[0] = best_off;
673 }
674 if (litLength == 0)
675 offset--;
676 }
677
678 ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
679 ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
680 anchor = ip = ip + mlen;
681 }
682 } /* for (cur=0; cur < last_pos; ) */
683
684 /* Save reps for next block */
685 {
686 int i;
687 for (i = 0; i < ZSTD_REP_NUM; i++)
688 ctx->repToConfirm[i] = rep[i];
689 }
690
691 /* Last Literals */
692 {
693 size_t const lastLLSize = iend - anchor;
694 memcpy(seqStorePtr->lit, anchor, lastLLSize);
695 seqStorePtr->lit += lastLLSize;
696 }
697}
698
699FORCE_INLINE
700void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra)
701{
702 seqStore_t *seqStorePtr = &(ctx->seqStore);
703 const BYTE *const istart = (const BYTE *)src;
704 const BYTE *ip = istart;
705 const BYTE *anchor = istart;
706 const BYTE *const iend = istart + srcSize;
707 const BYTE *const ilimit = iend - 8;
708 const BYTE *const base = ctx->base;
709 const U32 lowestIndex = ctx->lowLimit;
710 const U32 dictLimit = ctx->dictLimit;
711 const BYTE *const prefixStart = base + dictLimit;
712 const BYTE *const dictBase = ctx->dictBase;
713 const BYTE *const dictEnd = dictBase + dictLimit;
714
715 const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
716 const U32 sufficient_len = ctx->params.cParams.targetLength;
717 const U32 mls = ctx->params.cParams.searchLength;
718 const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
719
720 ZSTD_optimal_t *opt = seqStorePtr->priceTable;
721 ZSTD_match_t *matches = seqStorePtr->matchTable;
722 const BYTE *inr;
723
724 /* init */
725 U32 offset, rep[ZSTD_REP_NUM];
726 {
727 U32 i;
728 for (i = 0; i < ZSTD_REP_NUM; i++)
729 rep[i] = ctx->rep[i];
730 }
731
732 ctx->nextToUpdate3 = ctx->nextToUpdate;
733 ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize);
734 ip += (ip == prefixStart);
735
736 /* Match Loop */
737 while (ip < ilimit) {
738 U32 cur, match_num, last_pos, litlen, price;
739 U32 u, mlen, best_mlen, best_off, litLength;
740 U32 curr = (U32)(ip - base);
741 memset(opt, 0, sizeof(ZSTD_optimal_t));
742 last_pos = 0;
743 opt[0].litlen = (U32)(ip - anchor);
744
745 /* check repCode */
746 {
747 U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor);
748 for (i = (ip == anchor); i < last_i; i++) {
749 const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
750 const U32 repIndex = (U32)(curr - repCur);
751 const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
752 const BYTE *const repMatch = repBase + repIndex;
753 if ((repCur > 0 && repCur <= (S32)curr) &&
754 (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
755 && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) {
756 /* repcode detected we should take it */
757 const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
758 mlen = (U32)ZSTD_count_2segments(ip + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch;
759
760 if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
761 best_mlen = mlen;
762 best_off = i;
763 cur = 0;
764 last_pos = 1;
765 goto _storeSequence;
766 }
767
768 best_off = i - (ip == anchor);
769 litlen = opt[0].litlen;
770 do {
771 price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
772 if (mlen > last_pos || price < opt[mlen].price)
773 SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
774 mlen--;
775 } while (mlen >= minMatch);
776 }
777 }
778 }
779
780 match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, ip, iend, maxSearches, mls, matches, minMatch); /* first search (depth 0) */
781
782 if (!last_pos && !match_num) {
783 ip++;
784 continue;
785 }
786
787 {
788 U32 i;
789 for (i = 0; i < ZSTD_REP_NUM; i++)
790 opt[0].rep[i] = rep[i];
791 }
792 opt[0].mlen = 1;
793
794 if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
795 best_mlen = matches[match_num - 1].len;
796 best_off = matches[match_num - 1].off;
797 cur = 0;
798 last_pos = 1;
799 goto _storeSequence;
800 }
801
802 best_mlen = (last_pos) ? last_pos : minMatch;
803
804 /* set prices using matches at position = 0 */
805 for (u = 0; u < match_num; u++) {
806 mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
807 best_mlen = matches[u].len;
808 litlen = opt[0].litlen;
809 while (mlen <= best_mlen) {
810 price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
811 if (mlen > last_pos || price < opt[mlen].price)
812 SET_PRICE(mlen, mlen, matches[u].off, litlen, price);
813 mlen++;
814 }
815 }
816
817 if (last_pos < minMatch) {
818 ip++;
819 continue;
820 }
821
822 /* check further positions */
823 for (cur = 1; cur <= last_pos; cur++) {
824 inr = ip + cur;
825
826 if (opt[cur - 1].mlen == 1) {
827 litlen = opt[cur - 1].litlen + 1;
828 if (cur > litlen) {
829 price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen);
830 } else
831 price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
832 } else {
833 litlen = 1;
834 price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1);
835 }
836
837 if (cur > last_pos || price <= opt[cur].price)
838 SET_PRICE(cur, 1, 0, litlen, price);
839
840 if (cur == last_pos)
841 break;
842
843 if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */
844 continue;
845
846 mlen = opt[cur].mlen;
847 if (opt[cur].off > ZSTD_REP_MOVE_OPT) {
848 opt[cur].rep[2] = opt[cur - mlen].rep[1];
849 opt[cur].rep[1] = opt[cur - mlen].rep[0];
850 opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT;
851 } else {
852 opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2];
853 opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1];
854 opt[cur].rep[0] =
855 ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]);
856 }
857
858 best_mlen = minMatch;
859 {
860 U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1);
861 for (i = (mlen != 1); i < last_i; i++) {
862 const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
863 const U32 repIndex = (U32)(curr + cur - repCur);
864 const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
865 const BYTE *const repMatch = repBase + repIndex;
866 if ((repCur > 0 && repCur <= (S32)(curr + cur)) &&
867 (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
868 && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) {
869 /* repcode detected */
870 const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
871 mlen = (U32)ZSTD_count_2segments(inr + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch;
872
873 if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
874 best_mlen = mlen;
875 best_off = i;
876 last_pos = cur + 1;
877 goto _storeSequence;
878 }
879
880 best_off = i - (opt[cur].mlen != 1);
881 if (mlen > best_mlen)
882 best_mlen = mlen;
883
884 do {
885 if (opt[cur].mlen == 1) {
886 litlen = opt[cur].litlen;
887 if (cur > litlen) {
888 price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen,
889 best_off, mlen - MINMATCH, ultra);
890 } else
891 price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
892 } else {
893 litlen = 0;
894 price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra);
895 }
896
897 if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
898 SET_PRICE(cur + mlen, mlen, i, litlen, price);
899 mlen--;
900 } while (mlen >= minMatch);
901 }
902 }
903 }
904
905 match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, inr, iend, maxSearches, mls, matches, minMatch);
906
907 if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
908 best_mlen = matches[match_num - 1].len;
909 best_off = matches[match_num - 1].off;
910 last_pos = cur + 1;
911 goto _storeSequence;
912 }
913
914 /* set prices using matches at position = cur */
915 for (u = 0; u < match_num; u++) {
916 mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
917 best_mlen = matches[u].len;
918
919 while (mlen <= best_mlen) {
920 if (opt[cur].mlen == 1) {
921 litlen = opt[cur].litlen;
922 if (cur > litlen)
923 price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen,
924 matches[u].off - 1, mlen - MINMATCH, ultra);
925 else
926 price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
927 } else {
928 litlen = 0;
929 price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra);
930 }
931
932 if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
933 SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
934
935 mlen++;
936 }
937 }
938 } /* for (cur = 1; cur <= last_pos; cur++) */
939
940 best_mlen = opt[last_pos].mlen;
941 best_off = opt[last_pos].off;
942 cur = last_pos - best_mlen;
943
944 /* store sequence */
945_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */
946 opt[0].mlen = 1;
947
948 while (1) {
949 mlen = opt[cur].mlen;
950 offset = opt[cur].off;
951 opt[cur].mlen = best_mlen;
952 opt[cur].off = best_off;
953 best_mlen = mlen;
954 best_off = offset;
955 if (mlen > cur)
956 break;
957 cur -= mlen;
958 }
959
960 for (u = 0; u <= last_pos;) {
961 u += opt[u].mlen;
962 }
963
964 for (cur = 0; cur < last_pos;) {
965 mlen = opt[cur].mlen;
966 if (mlen == 1) {
967 ip++;
968 cur++;
969 continue;
970 }
971 offset = opt[cur].off;
972 cur += mlen;
973 litLength = (U32)(ip - anchor);
974
975 if (offset > ZSTD_REP_MOVE_OPT) {
976 rep[2] = rep[1];
977 rep[1] = rep[0];
978 rep[0] = offset - ZSTD_REP_MOVE_OPT;
979 offset--;
980 } else {
981 if (offset != 0) {
982 best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]);
983 if (offset != 1)
984 rep[2] = rep[1];
985 rep[1] = rep[0];
986 rep[0] = best_off;
987 }
988
989 if (litLength == 0)
990 offset--;
991 }
992
993 ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
994 ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
995 anchor = ip = ip + mlen;
996 }
997 } /* for (cur=0; cur < last_pos; ) */
998
999 /* Save reps for next block */
1000 {
1001 int i;
1002 for (i = 0; i < ZSTD_REP_NUM; i++)
1003 ctx->repToConfirm[i] = rep[i];
1004 }
1005
1006 /* Last Literals */
1007 {
1008 size_t lastLLSize = iend - anchor;
1009 memcpy(seqStorePtr->lit, anchor, lastLLSize);
1010 seqStorePtr->lit += lastLLSize;
1011 }
1012}
1013
1014#endif /* ZSTD_OPT_H_91842398743 */