1 /*
2 * Copyright (c) 2016-2020, Przemyslaw Skibinski, Yann Collet, Facebook, Inc.
3 * All rights reserved.
4 *
5 * This source code is licensed under both the BSD-style license (found in the
6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7 * in the COPYING file in the root directory of this source tree).
8 * You may select, at your option, one of the above-listed licenses.
9 */
10
11 #include "zstd_compress_internal.h"
12 #include "hist.h"
13 #include "zstd_opt.h"
14
15
16 #define ZSTD_LITFREQ_ADD 2 /* scaling factor for litFreq, so that frequencies adapt faster to new stats */
17 #define ZSTD_FREQ_DIV 4 /* log factor when using previous stats to init next stats */
18 #define ZSTD_MAX_PRICE (1<<30)
19
20 #define ZSTD_PREDEF_THRESHOLD 1024 /* if srcSize < ZSTD_PREDEF_THRESHOLD, symbols' cost is assumed static, directly determined by pre-defined distributions */
21
22
23 /*-*************************************
24 * Price functions for optimal parser
25 ***************************************/
26
27 #if 0 /* approximation at bit level */
28 # define BITCOST_ACCURACY 0
29 # define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
30 # define WEIGHT(stat) ((void)opt, ZSTD_bitWeight(stat))
31 #elif 0 /* fractional bit accuracy */
32 # define BITCOST_ACCURACY 8
33 # define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
34 # define WEIGHT(stat,opt) ((void)opt, ZSTD_fracWeight(stat))
35 #else /* opt==approx, ultra==accurate */
36 # define BITCOST_ACCURACY 8
37 # define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
38 # define WEIGHT(stat,opt) (opt ? ZSTD_fracWeight(stat) : ZSTD_bitWeight(stat))
39 #endif
40
ZSTD_bitWeight(U32 stat)41 MEM_STATIC U32 ZSTD_bitWeight(U32 stat)
42 {
43 return (ZSTD_highbit32(stat+1) * BITCOST_MULTIPLIER);
44 }
45
ZSTD_fracWeight(U32 rawStat)46 MEM_STATIC U32 ZSTD_fracWeight(U32 rawStat)
47 {
48 U32 const stat = rawStat + 1;
49 U32 const hb = ZSTD_highbit32(stat);
50 U32 const BWeight = hb * BITCOST_MULTIPLIER;
51 U32 const FWeight = (stat << BITCOST_ACCURACY) >> hb;
52 U32 const weight = BWeight + FWeight;
53 assert(hb + BITCOST_ACCURACY < 31);
54 return weight;
55 }
56
57 #if (DEBUGLEVEL>=2)
58 /* debugging function,
59 * @return price in bytes as fractional value
60 * for debug messages only */
ZSTD_fCost(U32 price)61 MEM_STATIC double ZSTD_fCost(U32 price)
62 {
63 return (double)price / (BITCOST_MULTIPLIER*8);
64 }
65 #endif
66
ZSTD_compressedLiterals(optState_t const * const optPtr)67 static int ZSTD_compressedLiterals(optState_t const* const optPtr)
68 {
69 return optPtr->literalCompressionMode != ZSTD_lcm_uncompressed;
70 }
71
ZSTD_setBasePrices(optState_t * optPtr,int optLevel)72 static void ZSTD_setBasePrices(optState_t* optPtr, int optLevel)
73 {
74 if (ZSTD_compressedLiterals(optPtr))
75 optPtr->litSumBasePrice = WEIGHT(optPtr->litSum, optLevel);
76 optPtr->litLengthSumBasePrice = WEIGHT(optPtr->litLengthSum, optLevel);
77 optPtr->matchLengthSumBasePrice = WEIGHT(optPtr->matchLengthSum, optLevel);
78 optPtr->offCodeSumBasePrice = WEIGHT(optPtr->offCodeSum, optLevel);
79 }
80
81
82 /* ZSTD_downscaleStat() :
83 * reduce all elements in table by a factor 2^(ZSTD_FREQ_DIV+malus)
84 * return the resulting sum of elements */
ZSTD_downscaleStat(unsigned * table,U32 lastEltIndex,int malus)85 static U32 ZSTD_downscaleStat(unsigned* table, U32 lastEltIndex, int malus)
86 {
87 U32 s, sum=0;
88 DEBUGLOG(5, "ZSTD_downscaleStat (nbElts=%u)", (unsigned)lastEltIndex+1);
89 assert(ZSTD_FREQ_DIV+malus > 0 && ZSTD_FREQ_DIV+malus < 31);
90 for (s=0; s<lastEltIndex+1; s++) {
91 table[s] = 1 + (table[s] >> (ZSTD_FREQ_DIV+malus));
92 sum += table[s];
93 }
94 return sum;
95 }
96
97 /* ZSTD_rescaleFreqs() :
98 * if first block (detected by optPtr->litLengthSum == 0) : init statistics
99 * take hints from dictionary if there is one
100 * or init from zero, using src for literals stats, or flat 1 for match symbols
101 * otherwise downscale existing stats, to be used as seed for next block.
102 */
103 static void
ZSTD_rescaleFreqs(optState_t * const optPtr,const BYTE * const src,size_t const srcSize,int const optLevel)104 ZSTD_rescaleFreqs(optState_t* const optPtr,
105 const BYTE* const src, size_t const srcSize,
106 int const optLevel)
107 {
108 int const compressedLiterals = ZSTD_compressedLiterals(optPtr);
109 DEBUGLOG(5, "ZSTD_rescaleFreqs (srcSize=%u)", (unsigned)srcSize);
110 optPtr->priceType = zop_dynamic;
111
112 if (optPtr->litLengthSum == 0) { /* first block : init */
113 if (srcSize <= ZSTD_PREDEF_THRESHOLD) { /* heuristic */
114 DEBUGLOG(5, "(srcSize <= ZSTD_PREDEF_THRESHOLD) => zop_predef");
115 optPtr->priceType = zop_predef;
116 }
117
118 assert(optPtr->symbolCosts != NULL);
119 if (optPtr->symbolCosts->huf.repeatMode == HUF_repeat_valid) {
120 /* huffman table presumed generated by dictionary */
121 optPtr->priceType = zop_dynamic;
122
123 if (compressedLiterals) {
124 unsigned lit;
125 assert(optPtr->litFreq != NULL);
126 optPtr->litSum = 0;
127 for (lit=0; lit<=MaxLit; lit++) {
128 U32 const scaleLog = 11; /* scale to 2K */
129 U32 const bitCost = HUF_getNbBits(optPtr->symbolCosts->huf.CTable, lit);
130 assert(bitCost <= scaleLog);
131 optPtr->litFreq[lit] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/;
132 optPtr->litSum += optPtr->litFreq[lit];
133 } }
134
135 { unsigned ll;
136 FSE_CState_t llstate;
137 FSE_initCState(&llstate, optPtr->symbolCosts->fse.litlengthCTable);
138 optPtr->litLengthSum = 0;
139 for (ll=0; ll<=MaxLL; ll++) {
140 U32 const scaleLog = 10; /* scale to 1K */
141 U32 const bitCost = FSE_getMaxNbBits(llstate.symbolTT, ll);
142 assert(bitCost < scaleLog);
143 optPtr->litLengthFreq[ll] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/;
144 optPtr->litLengthSum += optPtr->litLengthFreq[ll];
145 } }
146
147 { unsigned ml;
148 FSE_CState_t mlstate;
149 FSE_initCState(&mlstate, optPtr->symbolCosts->fse.matchlengthCTable);
150 optPtr->matchLengthSum = 0;
151 for (ml=0; ml<=MaxML; ml++) {
152 U32 const scaleLog = 10;
153 U32 const bitCost = FSE_getMaxNbBits(mlstate.symbolTT, ml);
154 assert(bitCost < scaleLog);
155 optPtr->matchLengthFreq[ml] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/;
156 optPtr->matchLengthSum += optPtr->matchLengthFreq[ml];
157 } }
158
159 { unsigned of;
160 FSE_CState_t ofstate;
161 FSE_initCState(&ofstate, optPtr->symbolCosts->fse.offcodeCTable);
162 optPtr->offCodeSum = 0;
163 for (of=0; of<=MaxOff; of++) {
164 U32 const scaleLog = 10;
165 U32 const bitCost = FSE_getMaxNbBits(ofstate.symbolTT, of);
166 assert(bitCost < scaleLog);
167 optPtr->offCodeFreq[of] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/;
168 optPtr->offCodeSum += optPtr->offCodeFreq[of];
169 } }
170
171 } else { /* not a dictionary */
172
173 assert(optPtr->litFreq != NULL);
174 if (compressedLiterals) {
175 unsigned lit = MaxLit;
176 HIST_count_simple(optPtr->litFreq, &lit, src, srcSize); /* use raw first block to init statistics */
177 optPtr->litSum = ZSTD_downscaleStat(optPtr->litFreq, MaxLit, 1);
178 }
179
180 { unsigned ll;
181 for (ll=0; ll<=MaxLL; ll++)
182 optPtr->litLengthFreq[ll] = 1;
183 }
184 optPtr->litLengthSum = MaxLL+1;
185
186 { unsigned ml;
187 for (ml=0; ml<=MaxML; ml++)
188 optPtr->matchLengthFreq[ml] = 1;
189 }
190 optPtr->matchLengthSum = MaxML+1;
191
192 { unsigned of;
193 for (of=0; of<=MaxOff; of++)
194 optPtr->offCodeFreq[of] = 1;
195 }
196 optPtr->offCodeSum = MaxOff+1;
197
198 }
199
200 } else { /* new block : re-use previous statistics, scaled down */
201
202 if (compressedLiterals)
203 optPtr->litSum = ZSTD_downscaleStat(optPtr->litFreq, MaxLit, 1);
204 optPtr->litLengthSum = ZSTD_downscaleStat(optPtr->litLengthFreq, MaxLL, 0);
205 optPtr->matchLengthSum = ZSTD_downscaleStat(optPtr->matchLengthFreq, MaxML, 0);
206 optPtr->offCodeSum = ZSTD_downscaleStat(optPtr->offCodeFreq, MaxOff, 0);
207 }
208
209 ZSTD_setBasePrices(optPtr, optLevel);
210 }
211
212 /* ZSTD_rawLiteralsCost() :
213 * price of literals (only) in specified segment (which length can be 0).
214 * does not include price of literalLength symbol */
ZSTD_rawLiteralsCost(const BYTE * const literals,U32 const litLength,const optState_t * const optPtr,int optLevel)215 static U32 ZSTD_rawLiteralsCost(const BYTE* const literals, U32 const litLength,
216 const optState_t* const optPtr,
217 int optLevel)
218 {
219 if (litLength == 0) return 0;
220
221 if (!ZSTD_compressedLiterals(optPtr))
222 return (litLength << 3) * BITCOST_MULTIPLIER; /* Uncompressed - 8 bytes per literal. */
223
224 if (optPtr->priceType == zop_predef)
225 return (litLength*6) * BITCOST_MULTIPLIER; /* 6 bit per literal - no statistic used */
226
227 /* dynamic statistics */
228 { U32 price = litLength * optPtr->litSumBasePrice;
229 U32 u;
230 for (u=0; u < litLength; u++) {
231 assert(WEIGHT(optPtr->litFreq[literals[u]], optLevel) <= optPtr->litSumBasePrice); /* literal cost should never be negative */
232 price -= WEIGHT(optPtr->litFreq[literals[u]], optLevel);
233 }
234 return price;
235 }
236 }
237
238 /* ZSTD_litLengthPrice() :
239 * cost of literalLength symbol */
ZSTD_litLengthPrice(U32 const litLength,const optState_t * const optPtr,int optLevel)240 static U32 ZSTD_litLengthPrice(U32 const litLength, const optState_t* const optPtr, int optLevel)
241 {
242 if (optPtr->priceType == zop_predef) return WEIGHT(litLength, optLevel);
243
244 /* dynamic statistics */
245 { U32 const llCode = ZSTD_LLcode(litLength);
246 return (LL_bits[llCode] * BITCOST_MULTIPLIER)
247 + optPtr->litLengthSumBasePrice
248 - WEIGHT(optPtr->litLengthFreq[llCode], optLevel);
249 }
250 }
251
252 /* ZSTD_getMatchPrice() :
253 * Provides the cost of the match part (offset + matchLength) of a sequence
254 * Must be combined with ZSTD_fullLiteralsCost() to get the full cost of a sequence.
255 * optLevel: when <2, favors small offset for decompression speed (improved cache efficiency) */
256 FORCE_INLINE_TEMPLATE U32
ZSTD_getMatchPrice(U32 const offset,U32 const matchLength,const optState_t * const optPtr,int const optLevel)257 ZSTD_getMatchPrice(U32 const offset,
258 U32 const matchLength,
259 const optState_t* const optPtr,
260 int const optLevel)
261 {
262 U32 price;
263 U32 const offCode = ZSTD_highbit32(offset+1);
264 U32 const mlBase = matchLength - MINMATCH;
265 assert(matchLength >= MINMATCH);
266
267 if (optPtr->priceType == zop_predef) /* fixed scheme, do not use statistics */
268 return WEIGHT(mlBase, optLevel) + ((16 + offCode) * BITCOST_MULTIPLIER);
269
270 /* dynamic statistics */
271 price = (offCode * BITCOST_MULTIPLIER) + (optPtr->offCodeSumBasePrice - WEIGHT(optPtr->offCodeFreq[offCode], optLevel));
272 if ((optLevel<2) /*static*/ && offCode >= 20)
273 price += (offCode-19)*2 * BITCOST_MULTIPLIER; /* handicap for long distance offsets, favor decompression speed */
274
275 /* match Length */
276 { U32 const mlCode = ZSTD_MLcode(mlBase);
277 price += (ML_bits[mlCode] * BITCOST_MULTIPLIER) + (optPtr->matchLengthSumBasePrice - WEIGHT(optPtr->matchLengthFreq[mlCode], optLevel));
278 }
279
280 price += BITCOST_MULTIPLIER / 5; /* heuristic : make matches a bit more costly to favor less sequences -> faster decompression speed */
281
282 DEBUGLOG(8, "ZSTD_getMatchPrice(ml:%u) = %u", matchLength, price);
283 return price;
284 }
285
286 /* ZSTD_updateStats() :
287 * assumption : literals + litLengtn <= iend */
ZSTD_updateStats(optState_t * const optPtr,U32 litLength,const BYTE * literals,U32 offsetCode,U32 matchLength)288 static void ZSTD_updateStats(optState_t* const optPtr,
289 U32 litLength, const BYTE* literals,
290 U32 offsetCode, U32 matchLength)
291 {
292 /* literals */
293 if (ZSTD_compressedLiterals(optPtr)) {
294 U32 u;
295 for (u=0; u < litLength; u++)
296 optPtr->litFreq[literals[u]] += ZSTD_LITFREQ_ADD;
297 optPtr->litSum += litLength*ZSTD_LITFREQ_ADD;
298 }
299
300 /* literal Length */
301 { U32 const llCode = ZSTD_LLcode(litLength);
302 optPtr->litLengthFreq[llCode]++;
303 optPtr->litLengthSum++;
304 }
305
306 /* match offset code (0-2=>repCode; 3+=>offset+2) */
307 { U32 const offCode = ZSTD_highbit32(offsetCode+1);
308 assert(offCode <= MaxOff);
309 optPtr->offCodeFreq[offCode]++;
310 optPtr->offCodeSum++;
311 }
312
313 /* match Length */
314 { U32 const mlBase = matchLength - MINMATCH;
315 U32 const mlCode = ZSTD_MLcode(mlBase);
316 optPtr->matchLengthFreq[mlCode]++;
317 optPtr->matchLengthSum++;
318 }
319 }
320
321
322 /* ZSTD_readMINMATCH() :
323 * function safe only for comparisons
324 * assumption : memPtr must be at least 4 bytes before end of buffer */
ZSTD_readMINMATCH(const void * memPtr,U32 length)325 MEM_STATIC U32 ZSTD_readMINMATCH(const void* memPtr, U32 length)
326 {
327 switch (length)
328 {
329 default :
330 case 4 : return MEM_read32(memPtr);
331 case 3 : if (MEM_isLittleEndian())
332 return MEM_read32(memPtr)<<8;
333 else
334 return MEM_read32(memPtr)>>8;
335 }
336 }
337
338
339 /* Update hashTable3 up to ip (excluded)
340 Assumption : always within prefix (i.e. not within extDict) */
ZSTD_insertAndFindFirstIndexHash3(ZSTD_matchState_t * ms,U32 * nextToUpdate3,const BYTE * const ip)341 static U32 ZSTD_insertAndFindFirstIndexHash3 (ZSTD_matchState_t* ms,
342 U32* nextToUpdate3,
343 const BYTE* const ip)
344 {
345 U32* const hashTable3 = ms->hashTable3;
346 U32 const hashLog3 = ms->hashLog3;
347 const BYTE* const base = ms->window.base;
348 U32 idx = *nextToUpdate3;
349 U32 const target = (U32)(ip - base);
350 size_t const hash3 = ZSTD_hash3Ptr(ip, hashLog3);
351 assert(hashLog3 > 0);
352
353 while(idx < target) {
354 hashTable3[ZSTD_hash3Ptr(base+idx, hashLog3)] = idx;
355 idx++;
356 }
357
358 *nextToUpdate3 = target;
359 return hashTable3[hash3];
360 }
361
362
363 /*-*************************************
364 * Binary Tree search
365 ***************************************/
366 /** ZSTD_insertBt1() : add one or multiple positions to tree.
367 * ip : assumed <= iend-8 .
368 * @return : nb of positions added */
ZSTD_insertBt1(ZSTD_matchState_t * ms,const BYTE * const ip,const BYTE * const iend,U32 const mls,const int extDict)369 static U32 ZSTD_insertBt1(
370 ZSTD_matchState_t* ms,
371 const BYTE* const ip, const BYTE* const iend,
372 U32 const mls, const int extDict)
373 {
374 const ZSTD_compressionParameters* const cParams = &ms->cParams;
375 U32* const hashTable = ms->hashTable;
376 U32 const hashLog = cParams->hashLog;
377 size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
378 U32* const bt = ms->chainTable;
379 U32 const btLog = cParams->chainLog - 1;
380 U32 const btMask = (1 << btLog) - 1;
381 U32 matchIndex = hashTable[h];
382 size_t commonLengthSmaller=0, commonLengthLarger=0;
383 const BYTE* const base = ms->window.base;
384 const BYTE* const dictBase = ms->window.dictBase;
385 const U32 dictLimit = ms->window.dictLimit;
386 const BYTE* const dictEnd = dictBase + dictLimit;
387 const BYTE* const prefixStart = base + dictLimit;
388 const BYTE* match;
389 const U32 curr = (U32)(ip-base);
390 const U32 btLow = btMask >= curr ? 0 : curr - btMask;
391 U32* smallerPtr = bt + 2*(curr&btMask);
392 U32* largerPtr = smallerPtr + 1;
393 U32 dummy32; /* to be nullified at the end */
394 U32 const windowLow = ms->window.lowLimit;
395 U32 matchEndIdx = curr+8+1;
396 size_t bestLength = 8;
397 U32 nbCompares = 1U << cParams->searchLog;
398 #ifdef ZSTD_C_PREDICT
399 U32 predictedSmall = *(bt + 2*((curr-1)&btMask) + 0);
400 U32 predictedLarge = *(bt + 2*((curr-1)&btMask) + 1);
401 predictedSmall += (predictedSmall>0);
402 predictedLarge += (predictedLarge>0);
403 #endif /* ZSTD_C_PREDICT */
404
405 DEBUGLOG(8, "ZSTD_insertBt1 (%u)", curr);
406
407 assert(ip <= iend-8); /* required for h calculation */
408 hashTable[h] = curr; /* Update Hash Table */
409
410 assert(windowLow > 0);
411 while (nbCompares-- && (matchIndex >= windowLow)) {
412 U32* const nextPtr = bt + 2*(matchIndex & btMask);
413 size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
414 assert(matchIndex < curr);
415
416 #ifdef ZSTD_C_PREDICT /* note : can create issues when hlog small <= 11 */
417 const U32* predictPtr = bt + 2*((matchIndex-1) & btMask); /* written this way, as bt is a roll buffer */
418 if (matchIndex == predictedSmall) {
419 /* no need to check length, result known */
420 *smallerPtr = matchIndex;
421 if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop the search */
422 smallerPtr = nextPtr+1; /* new "smaller" => larger of match */
423 matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to current) */
424 predictedSmall = predictPtr[1] + (predictPtr[1]>0);
425 continue;
426 }
427 if (matchIndex == predictedLarge) {
428 *largerPtr = matchIndex;
429 if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop the search */
430 largerPtr = nextPtr;
431 matchIndex = nextPtr[0];
432 predictedLarge = predictPtr[0] + (predictPtr[0]>0);
433 continue;
434 }
435 #endif
436
437 if (!extDict || (matchIndex+matchLength >= dictLimit)) {
438 assert(matchIndex+matchLength >= dictLimit); /* might be wrong if actually extDict */
439 match = base + matchIndex;
440 matchLength += ZSTD_count(ip+matchLength, match+matchLength, iend);
441 } else {
442 match = dictBase + matchIndex;
443 matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iend, dictEnd, prefixStart);
444 if (matchIndex+matchLength >= dictLimit)
445 match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
446 }
447
448 if (matchLength > bestLength) {
449 bestLength = matchLength;
450 if (matchLength > matchEndIdx - matchIndex)
451 matchEndIdx = matchIndex + (U32)matchLength;
452 }
453
454 if (ip+matchLength == iend) { /* equal : no way to know if inf or sup */
455 break; /* drop , to guarantee consistency ; miss a bit of compression, but other solutions can corrupt tree */
456 }
457
458 if (match[matchLength] < ip[matchLength]) { /* necessarily within buffer */
459 /* match is smaller than current */
460 *smallerPtr = matchIndex; /* update smaller idx */
461 commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
462 if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop searching */
463 smallerPtr = nextPtr+1; /* new "candidate" => larger than match, which was smaller than target */
464 matchIndex = nextPtr[1]; /* new matchIndex, larger than previous and closer to current */
465 } else {
466 /* match is larger than current */
467 *largerPtr = matchIndex;
468 commonLengthLarger = matchLength;
469 if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop searching */
470 largerPtr = nextPtr;
471 matchIndex = nextPtr[0];
472 } }
473
474 *smallerPtr = *largerPtr = 0;
475 { U32 positions = 0;
476 if (bestLength > 384) positions = MIN(192, (U32)(bestLength - 384)); /* speed optimization */
477 assert(matchEndIdx > curr + 8);
478 return MAX(positions, matchEndIdx - (curr + 8));
479 }
480 }
481
482 FORCE_INLINE_TEMPLATE
ZSTD_updateTree_internal(ZSTD_matchState_t * ms,const BYTE * const ip,const BYTE * const iend,const U32 mls,const ZSTD_dictMode_e dictMode)483 void ZSTD_updateTree_internal(
484 ZSTD_matchState_t* ms,
485 const BYTE* const ip, const BYTE* const iend,
486 const U32 mls, const ZSTD_dictMode_e dictMode)
487 {
488 const BYTE* const base = ms->window.base;
489 U32 const target = (U32)(ip - base);
490 U32 idx = ms->nextToUpdate;
491 DEBUGLOG(6, "ZSTD_updateTree_internal, from %u to %u (dictMode:%u)",
492 idx, target, dictMode);
493
494 while(idx < target) {
495 U32 const forward = ZSTD_insertBt1(ms, base+idx, iend, mls, dictMode == ZSTD_extDict);
496 assert(idx < (U32)(idx + forward));
497 idx += forward;
498 }
499 assert((size_t)(ip - base) <= (size_t)(U32)(-1));
500 assert((size_t)(iend - base) <= (size_t)(U32)(-1));
501 ms->nextToUpdate = target;
502 }
503
ZSTD_updateTree(ZSTD_matchState_t * ms,const BYTE * ip,const BYTE * iend)504 void ZSTD_updateTree(ZSTD_matchState_t* ms, const BYTE* ip, const BYTE* iend) {
505 ZSTD_updateTree_internal(ms, ip, iend, ms->cParams.minMatch, ZSTD_noDict);
506 }
507
508 FORCE_INLINE_TEMPLATE
ZSTD_insertBtAndGetAllMatches(ZSTD_match_t * matches,ZSTD_matchState_t * ms,U32 * nextToUpdate3,const BYTE * const ip,const BYTE * const iLimit,const ZSTD_dictMode_e dictMode,const U32 rep[ZSTD_REP_NUM],U32 const ll0,const U32 lengthToBeat,U32 const mls)509 U32 ZSTD_insertBtAndGetAllMatches (
510 ZSTD_match_t* matches, /* store result (found matches) in this table (presumed large enough) */
511 ZSTD_matchState_t* ms,
512 U32* nextToUpdate3,
513 const BYTE* const ip, const BYTE* const iLimit, const ZSTD_dictMode_e dictMode,
514 const U32 rep[ZSTD_REP_NUM],
515 U32 const ll0, /* tells if associated literal length is 0 or not. This value must be 0 or 1 */
516 const U32 lengthToBeat,
517 U32 const mls /* template */)
518 {
519 const ZSTD_compressionParameters* const cParams = &ms->cParams;
520 U32 const sufficient_len = MIN(cParams->targetLength, ZSTD_OPT_NUM -1);
521 const BYTE* const base = ms->window.base;
522 U32 const curr = (U32)(ip-base);
523 U32 const hashLog = cParams->hashLog;
524 U32 const minMatch = (mls==3) ? 3 : 4;
525 U32* const hashTable = ms->hashTable;
526 size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
527 U32 matchIndex = hashTable[h];
528 U32* const bt = ms->chainTable;
529 U32 const btLog = cParams->chainLog - 1;
530 U32 const btMask= (1U << btLog) - 1;
531 size_t commonLengthSmaller=0, commonLengthLarger=0;
532 const BYTE* const dictBase = ms->window.dictBase;
533 U32 const dictLimit = ms->window.dictLimit;
534 const BYTE* const dictEnd = dictBase + dictLimit;
535 const BYTE* const prefixStart = base + dictLimit;
536 U32 const btLow = (btMask >= curr) ? 0 : curr - btMask;
537 U32 const windowLow = ZSTD_getLowestMatchIndex(ms, curr, cParams->windowLog);
538 U32 const matchLow = windowLow ? windowLow : 1;
539 U32* smallerPtr = bt + 2*(curr&btMask);
540 U32* largerPtr = bt + 2*(curr&btMask) + 1;
541 U32 matchEndIdx = curr+8+1; /* farthest referenced position of any match => detects repetitive patterns */
542 U32 dummy32; /* to be nullified at the end */
543 U32 mnum = 0;
544 U32 nbCompares = 1U << cParams->searchLog;
545
546 const ZSTD_matchState_t* dms = dictMode == ZSTD_dictMatchState ? ms->dictMatchState : NULL;
547 const ZSTD_compressionParameters* const dmsCParams =
548 dictMode == ZSTD_dictMatchState ? &dms->cParams : NULL;
549 const BYTE* const dmsBase = dictMode == ZSTD_dictMatchState ? dms->window.base : NULL;
550 const BYTE* const dmsEnd = dictMode == ZSTD_dictMatchState ? dms->window.nextSrc : NULL;
551 U32 const dmsHighLimit = dictMode == ZSTD_dictMatchState ? (U32)(dmsEnd - dmsBase) : 0;
552 U32 const dmsLowLimit = dictMode == ZSTD_dictMatchState ? dms->window.lowLimit : 0;
553 U32 const dmsIndexDelta = dictMode == ZSTD_dictMatchState ? windowLow - dmsHighLimit : 0;
554 U32 const dmsHashLog = dictMode == ZSTD_dictMatchState ? dmsCParams->hashLog : hashLog;
555 U32 const dmsBtLog = dictMode == ZSTD_dictMatchState ? dmsCParams->chainLog - 1 : btLog;
556 U32 const dmsBtMask = dictMode == ZSTD_dictMatchState ? (1U << dmsBtLog) - 1 : 0;
557 U32 const dmsBtLow = dictMode == ZSTD_dictMatchState && dmsBtMask < dmsHighLimit - dmsLowLimit ? dmsHighLimit - dmsBtMask : dmsLowLimit;
558
559 size_t bestLength = lengthToBeat-1;
560 DEBUGLOG(8, "ZSTD_insertBtAndGetAllMatches: current=%u", curr);
561
562 /* check repCode */
563 assert(ll0 <= 1); /* necessarily 1 or 0 */
564 { U32 const lastR = ZSTD_REP_NUM + ll0;
565 U32 repCode;
566 for (repCode = ll0; repCode < lastR; repCode++) {
567 U32 const repOffset = (repCode==ZSTD_REP_NUM) ? (rep[0] - 1) : rep[repCode];
568 U32 const repIndex = curr - repOffset;
569 U32 repLen = 0;
570 assert(curr >= dictLimit);
571 if (repOffset-1 /* intentional overflow, discards 0 and -1 */ < curr-dictLimit) { /* equivalent to `curr > repIndex >= dictLimit` */
572 /* We must validate the repcode offset because when we're using a dictionary the
573 * valid offset range shrinks when the dictionary goes out of bounds.
574 */
575 if ((repIndex >= windowLow) & (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repOffset, minMatch))) {
576 repLen = (U32)ZSTD_count(ip+minMatch, ip+minMatch-repOffset, iLimit) + minMatch;
577 }
578 } else { /* repIndex < dictLimit || repIndex >= curr */
579 const BYTE* const repMatch = dictMode == ZSTD_dictMatchState ?
580 dmsBase + repIndex - dmsIndexDelta :
581 dictBase + repIndex;
582 assert(curr >= windowLow);
583 if ( dictMode == ZSTD_extDict
584 && ( ((repOffset-1) /*intentional overflow*/ < curr - windowLow) /* equivalent to `curr > repIndex >= windowLow` */
585 & (((U32)((dictLimit-1) - repIndex) >= 3) ) /* intentional overflow : do not test positions overlapping 2 memory segments */)
586 && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch)) ) {
587 repLen = (U32)ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iLimit, dictEnd, prefixStart) + minMatch;
588 }
589 if (dictMode == ZSTD_dictMatchState
590 && ( ((repOffset-1) /*intentional overflow*/ < curr - (dmsLowLimit + dmsIndexDelta)) /* equivalent to `curr > repIndex >= dmsLowLimit` */
591 & ((U32)((dictLimit-1) - repIndex) >= 3) ) /* intentional overflow : do not test positions overlapping 2 memory segments */
592 && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch)) ) {
593 repLen = (U32)ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iLimit, dmsEnd, prefixStart) + minMatch;
594 } }
595 /* save longer solution */
596 if (repLen > bestLength) {
597 DEBUGLOG(8, "found repCode %u (ll0:%u, offset:%u) of length %u",
598 repCode, ll0, repOffset, repLen);
599 bestLength = repLen;
600 matches[mnum].off = repCode - ll0;
601 matches[mnum].len = (U32)repLen;
602 mnum++;
603 if ( (repLen > sufficient_len)
604 | (ip+repLen == iLimit) ) { /* best possible */
605 return mnum;
606 } } } }
607
608 /* HC3 match finder */
609 if ((mls == 3) /*static*/ && (bestLength < mls)) {
610 U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3(ms, nextToUpdate3, ip);
611 if ((matchIndex3 >= matchLow)
612 & (curr - matchIndex3 < (1<<18)) /*heuristic : longer distance likely too expensive*/ ) {
613 size_t mlen;
614 if ((dictMode == ZSTD_noDict) /*static*/ || (dictMode == ZSTD_dictMatchState) /*static*/ || (matchIndex3 >= dictLimit)) {
615 const BYTE* const match = base + matchIndex3;
616 mlen = ZSTD_count(ip, match, iLimit);
617 } else {
618 const BYTE* const match = dictBase + matchIndex3;
619 mlen = ZSTD_count_2segments(ip, match, iLimit, dictEnd, prefixStart);
620 }
621
622 /* save best solution */
623 if (mlen >= mls /* == 3 > bestLength */) {
624 DEBUGLOG(8, "found small match with hlog3, of length %u",
625 (U32)mlen);
626 bestLength = mlen;
627 assert(curr > matchIndex3);
628 assert(mnum==0); /* no prior solution */
629 matches[0].off = (curr - matchIndex3) + ZSTD_REP_MOVE;
630 matches[0].len = (U32)mlen;
631 mnum = 1;
632 if ( (mlen > sufficient_len) |
633 (ip+mlen == iLimit) ) { /* best possible length */
634 ms->nextToUpdate = curr+1; /* skip insertion */
635 return 1;
636 } } }
637 /* no dictMatchState lookup: dicts don't have a populated HC3 table */
638 }
639
640 hashTable[h] = curr; /* Update Hash Table */
641
642 while (nbCompares-- && (matchIndex >= matchLow)) {
643 U32* const nextPtr = bt + 2*(matchIndex & btMask);
644 const BYTE* match;
645 size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
646 assert(curr > matchIndex);
647
648 if ((dictMode == ZSTD_noDict) || (dictMode == ZSTD_dictMatchState) || (matchIndex+matchLength >= dictLimit)) {
649 assert(matchIndex+matchLength >= dictLimit); /* ensure the condition is correct when !extDict */
650 match = base + matchIndex;
651 if (matchIndex >= dictLimit) assert(memcmp(match, ip, matchLength) == 0); /* ensure early section of match is equal as expected */
652 matchLength += ZSTD_count(ip+matchLength, match+matchLength, iLimit);
653 } else {
654 match = dictBase + matchIndex;
655 assert(memcmp(match, ip, matchLength) == 0); /* ensure early section of match is equal as expected */
656 matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iLimit, dictEnd, prefixStart);
657 if (matchIndex+matchLength >= dictLimit)
658 match = base + matchIndex; /* prepare for match[matchLength] read */
659 }
660
661 if (matchLength > bestLength) {
662 DEBUGLOG(8, "found match of length %u at distance %u (offCode=%u)",
663 (U32)matchLength, curr - matchIndex, curr - matchIndex + ZSTD_REP_MOVE);
664 assert(matchEndIdx > matchIndex);
665 if (matchLength > matchEndIdx - matchIndex)
666 matchEndIdx = matchIndex + (U32)matchLength;
667 bestLength = matchLength;
668 matches[mnum].off = (curr - matchIndex) + ZSTD_REP_MOVE;
669 matches[mnum].len = (U32)matchLength;
670 mnum++;
671 if ( (matchLength > ZSTD_OPT_NUM)
672 | (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */) {
673 if (dictMode == ZSTD_dictMatchState) nbCompares = 0; /* break should also skip searching dms */
674 break; /* drop, to preserve bt consistency (miss a little bit of compression) */
675 }
676 }
677
678 if (match[matchLength] < ip[matchLength]) {
679 /* match smaller than current */
680 *smallerPtr = matchIndex; /* update smaller idx */
681 commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
682 if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop the search */
683 smallerPtr = nextPtr+1; /* new candidate => larger than match, which was smaller than current */
684 matchIndex = nextPtr[1]; /* new matchIndex, larger than previous, closer to current */
685 } else {
686 *largerPtr = matchIndex;
687 commonLengthLarger = matchLength;
688 if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop the search */
689 largerPtr = nextPtr;
690 matchIndex = nextPtr[0];
691 } }
692
693 *smallerPtr = *largerPtr = 0;
694
695 if (dictMode == ZSTD_dictMatchState && nbCompares) {
696 size_t const dmsH = ZSTD_hashPtr(ip, dmsHashLog, mls);
697 U32 dictMatchIndex = dms->hashTable[dmsH];
698 const U32* const dmsBt = dms->chainTable;
699 commonLengthSmaller = commonLengthLarger = 0;
700 while (nbCompares-- && (dictMatchIndex > dmsLowLimit)) {
701 const U32* const nextPtr = dmsBt + 2*(dictMatchIndex & dmsBtMask);
702 size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
703 const BYTE* match = dmsBase + dictMatchIndex;
704 matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iLimit, dmsEnd, prefixStart);
705 if (dictMatchIndex+matchLength >= dmsHighLimit)
706 match = base + dictMatchIndex + dmsIndexDelta; /* to prepare for next usage of match[matchLength] */
707
708 if (matchLength > bestLength) {
709 matchIndex = dictMatchIndex + dmsIndexDelta;
710 DEBUGLOG(8, "found dms match of length %u at distance %u (offCode=%u)",
711 (U32)matchLength, curr - matchIndex, curr - matchIndex + ZSTD_REP_MOVE);
712 if (matchLength > matchEndIdx - matchIndex)
713 matchEndIdx = matchIndex + (U32)matchLength;
714 bestLength = matchLength;
715 matches[mnum].off = (curr - matchIndex) + ZSTD_REP_MOVE;
716 matches[mnum].len = (U32)matchLength;
717 mnum++;
718 if ( (matchLength > ZSTD_OPT_NUM)
719 | (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */) {
720 break; /* drop, to guarantee consistency (miss a little bit of compression) */
721 }
722 }
723
724 if (dictMatchIndex <= dmsBtLow) { break; } /* beyond tree size, stop the search */
725 if (match[matchLength] < ip[matchLength]) {
726 commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
727 dictMatchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to current) */
728 } else {
729 /* match is larger than current */
730 commonLengthLarger = matchLength;
731 dictMatchIndex = nextPtr[0];
732 }
733 }
734 }
735
736 assert(matchEndIdx > curr+8);
737 ms->nextToUpdate = matchEndIdx - 8; /* skip repetitive patterns */
738 return mnum;
739 }
740
741
ZSTD_BtGetAllMatches(ZSTD_match_t * matches,ZSTD_matchState_t * ms,U32 * nextToUpdate3,const BYTE * ip,const BYTE * const iHighLimit,const ZSTD_dictMode_e dictMode,const U32 rep[ZSTD_REP_NUM],U32 const ll0,U32 const lengthToBeat)742 FORCE_INLINE_TEMPLATE U32 ZSTD_BtGetAllMatches (
743 ZSTD_match_t* matches, /* store result (match found, increasing size) in this table */
744 ZSTD_matchState_t* ms,
745 U32* nextToUpdate3,
746 const BYTE* ip, const BYTE* const iHighLimit, const ZSTD_dictMode_e dictMode,
747 const U32 rep[ZSTD_REP_NUM],
748 U32 const ll0,
749 U32 const lengthToBeat)
750 {
751 const ZSTD_compressionParameters* const cParams = &ms->cParams;
752 U32 const matchLengthSearch = cParams->minMatch;
753 DEBUGLOG(8, "ZSTD_BtGetAllMatches");
754 if (ip < ms->window.base + ms->nextToUpdate) return 0; /* skipped area */
755 ZSTD_updateTree_internal(ms, ip, iHighLimit, matchLengthSearch, dictMode);
756 switch(matchLengthSearch)
757 {
758 case 3 : return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, 3);
759 default :
760 case 4 : return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, 4);
761 case 5 : return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, 5);
762 case 7 :
763 case 6 : return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, 6);
764 }
765 }
766
767 /*************************
768 * LDM helper functions *
769 *************************/
770
771 /* Struct containing info needed to make decision about ldm inclusion */
772 typedef struct {
773 rawSeqStore_t seqStore; /* External match candidates store for this block */
774 U32 startPosInBlock; /* Start position of the current match candidate */
775 U32 endPosInBlock; /* End position of the current match candidate */
776 U32 offset; /* Offset of the match candidate */
777 } ZSTD_optLdm_t;
778
779 /* ZSTD_optLdm_skipRawSeqStoreBytes():
780 * Moves forward in rawSeqStore by nbBytes, which will update the fields 'pos' and 'posInSequence'.
781 */
ZSTD_optLdm_skipRawSeqStoreBytes(rawSeqStore_t * rawSeqStore,size_t nbBytes)782 static void ZSTD_optLdm_skipRawSeqStoreBytes(rawSeqStore_t* rawSeqStore, size_t nbBytes) {
783 U32 currPos = (U32)(rawSeqStore->posInSequence + nbBytes);
784 while (currPos && rawSeqStore->pos < rawSeqStore->size) {
785 rawSeq currSeq = rawSeqStore->seq[rawSeqStore->pos];
786 if (currPos >= currSeq.litLength + currSeq.matchLength) {
787 currPos -= currSeq.litLength + currSeq.matchLength;
788 rawSeqStore->pos++;
789 } else {
790 rawSeqStore->posInSequence = currPos;
791 break;
792 }
793 }
794 if (currPos == 0 || rawSeqStore->pos == rawSeqStore->size) {
795 rawSeqStore->posInSequence = 0;
796 }
797 }
798
799 /* ZSTD_opt_getNextMatchAndUpdateSeqStore():
800 * Calculates the beginning and end of the next match in the current block.
801 * Updates 'pos' and 'posInSequence' of the ldmSeqStore.
802 */
ZSTD_opt_getNextMatchAndUpdateSeqStore(ZSTD_optLdm_t * optLdm,U32 currPosInBlock,U32 blockBytesRemaining)803 static void ZSTD_opt_getNextMatchAndUpdateSeqStore(ZSTD_optLdm_t* optLdm, U32 currPosInBlock,
804 U32 blockBytesRemaining) {
805 rawSeq currSeq;
806 U32 currBlockEndPos;
807 U32 literalsBytesRemaining;
808 U32 matchBytesRemaining;
809
810 /* Setting match end position to MAX to ensure we never use an LDM during this block */
811 if (optLdm->seqStore.size == 0 || optLdm->seqStore.pos >= optLdm->seqStore.size) {
812 optLdm->startPosInBlock = UINT_MAX;
813 optLdm->endPosInBlock = UINT_MAX;
814 return;
815 }
816 /* Calculate appropriate bytes left in matchLength and litLength after adjusting
817 based on ldmSeqStore->posInSequence */
818 currSeq = optLdm->seqStore.seq[optLdm->seqStore.pos];
819 assert(optLdm->seqStore.posInSequence <= currSeq.litLength + currSeq.matchLength);
820 currBlockEndPos = currPosInBlock + blockBytesRemaining;
821 literalsBytesRemaining = (optLdm->seqStore.posInSequence < currSeq.litLength) ?
822 currSeq.litLength - (U32)optLdm->seqStore.posInSequence :
823 0;
824 matchBytesRemaining = (literalsBytesRemaining == 0) ?
825 currSeq.matchLength - ((U32)optLdm->seqStore.posInSequence - currSeq.litLength) :
826 currSeq.matchLength;
827
828 /* If there are more literal bytes than bytes remaining in block, no ldm is possible */
829 if (literalsBytesRemaining >= blockBytesRemaining) {
830 optLdm->startPosInBlock = UINT_MAX;
831 optLdm->endPosInBlock = UINT_MAX;
832 ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, blockBytesRemaining);
833 return;
834 }
835
836 /* Matches may be < MINMATCH by this process. In that case, we will reject them
837 when we are deciding whether or not to add the ldm */
838 optLdm->startPosInBlock = currPosInBlock + literalsBytesRemaining;
839 optLdm->endPosInBlock = optLdm->startPosInBlock + matchBytesRemaining;
840 optLdm->offset = currSeq.offset;
841
842 if (optLdm->endPosInBlock > currBlockEndPos) {
843 /* Match ends after the block ends, we can't use the whole match */
844 optLdm->endPosInBlock = currBlockEndPos;
845 ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, currBlockEndPos - currPosInBlock);
846 } else {
847 /* Consume nb of bytes equal to size of sequence left */
848 ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, literalsBytesRemaining + matchBytesRemaining);
849 }
850 }
851
852 /* ZSTD_optLdm_maybeAddMatch():
853 * Adds a match if it's long enough, based on it's 'matchStartPosInBlock'
854 * and 'matchEndPosInBlock', into 'matches'. Maintains the correct ordering of 'matches'
855 */
ZSTD_optLdm_maybeAddMatch(ZSTD_match_t * matches,U32 * nbMatches,ZSTD_optLdm_t * optLdm,U32 currPosInBlock)856 static void ZSTD_optLdm_maybeAddMatch(ZSTD_match_t* matches, U32* nbMatches,
857 ZSTD_optLdm_t* optLdm, U32 currPosInBlock) {
858 U32 posDiff = currPosInBlock - optLdm->startPosInBlock;
859 /* Note: ZSTD_match_t actually contains offCode and matchLength (before subtracting MINMATCH) */
860 U32 candidateMatchLength = optLdm->endPosInBlock - optLdm->startPosInBlock - posDiff;
861 U32 candidateOffCode = optLdm->offset + ZSTD_REP_MOVE;
862
863 /* Ensure that current block position is not outside of the match */
864 if (currPosInBlock < optLdm->startPosInBlock
865 || currPosInBlock >= optLdm->endPosInBlock
866 || candidateMatchLength < MINMATCH) {
867 return;
868 }
869
870 if (*nbMatches == 0 || ((candidateMatchLength > matches[*nbMatches-1].len) && *nbMatches < ZSTD_OPT_NUM)) {
871 DEBUGLOG(6, "ZSTD_optLdm_maybeAddMatch(): Adding ldm candidate match (offCode: %u matchLength %u) at block position=%u",
872 candidateOffCode, candidateMatchLength, currPosInBlock);
873 matches[*nbMatches].len = candidateMatchLength;
874 matches[*nbMatches].off = candidateOffCode;
875 (*nbMatches)++;
876 }
877 }
878
879 /* ZSTD_optLdm_processMatchCandidate():
880 * Wrapper function to update ldm seq store and call ldm functions as necessary.
881 */
ZSTD_optLdm_processMatchCandidate(ZSTD_optLdm_t * optLdm,ZSTD_match_t * matches,U32 * nbMatches,U32 currPosInBlock,U32 remainingBytes)882 static void ZSTD_optLdm_processMatchCandidate(ZSTD_optLdm_t* optLdm, ZSTD_match_t* matches, U32* nbMatches,
883 U32 currPosInBlock, U32 remainingBytes) {
884 if (optLdm->seqStore.size == 0 || optLdm->seqStore.pos >= optLdm->seqStore.size) {
885 return;
886 }
887
888 if (currPosInBlock >= optLdm->endPosInBlock) {
889 if (currPosInBlock > optLdm->endPosInBlock) {
890 /* The position at which ZSTD_optLdm_processMatchCandidate() is called is not necessarily
891 * at the end of a match from the ldm seq store, and will often be some bytes
892 * over beyond matchEndPosInBlock. As such, we need to correct for these "overshoots"
893 */
894 U32 posOvershoot = currPosInBlock - optLdm->endPosInBlock;
895 ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, posOvershoot);
896 }
897 ZSTD_opt_getNextMatchAndUpdateSeqStore(optLdm, currPosInBlock, remainingBytes);
898 }
899 ZSTD_optLdm_maybeAddMatch(matches, nbMatches, optLdm, currPosInBlock);
900 }
901
902 /*-*******************************
903 * Optimal parser
904 *********************************/
905
906
ZSTD_totalLen(ZSTD_optimal_t sol)907 static U32 ZSTD_totalLen(ZSTD_optimal_t sol)
908 {
909 return sol.litlen + sol.mlen;
910 }
911
912 #if 0 /* debug */
913
914 static void
915 listStats(const U32* table, int lastEltID)
916 {
917 int const nbElts = lastEltID + 1;
918 int enb;
919 for (enb=0; enb < nbElts; enb++) {
920 (void)table;
921 /* RAWLOG(2, "%3i:%3i, ", enb, table[enb]); */
922 RAWLOG(2, "%4i,", table[enb]);
923 }
924 RAWLOG(2, " \n");
925 }
926
927 #endif
928
929 FORCE_INLINE_TEMPLATE size_t
ZSTD_compressBlock_opt_generic(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize,const int optLevel,const ZSTD_dictMode_e dictMode)930 ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms,
931 seqStore_t* seqStore,
932 U32 rep[ZSTD_REP_NUM],
933 const void* src, size_t srcSize,
934 const int optLevel,
935 const ZSTD_dictMode_e dictMode)
936 {
937 optState_t* const optStatePtr = &ms->opt;
938 const BYTE* const istart = (const BYTE*)src;
939 const BYTE* ip = istart;
940 const BYTE* anchor = istart;
941 const BYTE* const iend = istart + srcSize;
942 const BYTE* const ilimit = iend - 8;
943 const BYTE* const base = ms->window.base;
944 const BYTE* const prefixStart = base + ms->window.dictLimit;
945 const ZSTD_compressionParameters* const cParams = &ms->cParams;
946
947 U32 const sufficient_len = MIN(cParams->targetLength, ZSTD_OPT_NUM -1);
948 U32 const minMatch = (cParams->minMatch == 3) ? 3 : 4;
949 U32 nextToUpdate3 = ms->nextToUpdate;
950
951 ZSTD_optimal_t* const opt = optStatePtr->priceTable;
952 ZSTD_match_t* const matches = optStatePtr->matchTable;
953 ZSTD_optimal_t lastSequence;
954 ZSTD_optLdm_t optLdm;
955
956 optLdm.seqStore = ms->ldmSeqStore ? *ms->ldmSeqStore : kNullRawSeqStore;
957 optLdm.endPosInBlock = optLdm.startPosInBlock = optLdm.offset = 0;
958 ZSTD_opt_getNextMatchAndUpdateSeqStore(&optLdm, (U32)(ip-istart), (U32)(iend-ip));
959
960 /* init */
961 DEBUGLOG(5, "ZSTD_compressBlock_opt_generic: current=%u, prefix=%u, nextToUpdate=%u",
962 (U32)(ip - base), ms->window.dictLimit, ms->nextToUpdate);
963 assert(optLevel <= 2);
964 ZSTD_rescaleFreqs(optStatePtr, (const BYTE*)src, srcSize, optLevel);
965 ip += (ip==prefixStart);
966
967 /* Match Loop */
968 while (ip < ilimit) {
969 U32 cur, last_pos = 0;
970
971 /* find first match */
972 { U32 const litlen = (U32)(ip - anchor);
973 U32 const ll0 = !litlen;
974 U32 nbMatches = ZSTD_BtGetAllMatches(matches, ms, &nextToUpdate3, ip, iend, dictMode, rep, ll0, minMatch);
975 ZSTD_optLdm_processMatchCandidate(&optLdm, matches, &nbMatches,
976 (U32)(ip-istart), (U32)(iend - ip));
977 if (!nbMatches) { ip++; continue; }
978
979 /* initialize opt[0] */
980 { U32 i ; for (i=0; i<ZSTD_REP_NUM; i++) opt[0].rep[i] = rep[i]; }
981 opt[0].mlen = 0; /* means is_a_literal */
982 opt[0].litlen = litlen;
983 /* We don't need to include the actual price of the literals because
984 * it is static for the duration of the forward pass, and is included
985 * in every price. We include the literal length to avoid negative
986 * prices when we subtract the previous literal length.
987 */
988 opt[0].price = ZSTD_litLengthPrice(litlen, optStatePtr, optLevel);
989
990 /* large match -> immediate encoding */
991 { U32 const maxML = matches[nbMatches-1].len;
992 U32 const maxOffset = matches[nbMatches-1].off;
993 DEBUGLOG(6, "found %u matches of maxLength=%u and maxOffCode=%u at cPos=%u => start new series",
994 nbMatches, maxML, maxOffset, (U32)(ip-prefixStart));
995
996 if (maxML > sufficient_len) {
997 lastSequence.litlen = litlen;
998 lastSequence.mlen = maxML;
999 lastSequence.off = maxOffset;
1000 DEBUGLOG(6, "large match (%u>%u), immediate encoding",
1001 maxML, sufficient_len);
1002 cur = 0;
1003 last_pos = ZSTD_totalLen(lastSequence);
1004 goto _shortestPath;
1005 } }
1006
1007 /* set prices for first matches starting position == 0 */
1008 { U32 const literalsPrice = opt[0].price + ZSTD_litLengthPrice(0, optStatePtr, optLevel);
1009 U32 pos;
1010 U32 matchNb;
1011 for (pos = 1; pos < minMatch; pos++) {
1012 opt[pos].price = ZSTD_MAX_PRICE; /* mlen, litlen and price will be fixed during forward scanning */
1013 }
1014 for (matchNb = 0; matchNb < nbMatches; matchNb++) {
1015 U32 const offset = matches[matchNb].off;
1016 U32 const end = matches[matchNb].len;
1017 for ( ; pos <= end ; pos++ ) {
1018 U32 const matchPrice = ZSTD_getMatchPrice(offset, pos, optStatePtr, optLevel);
1019 U32 const sequencePrice = literalsPrice + matchPrice;
1020 DEBUGLOG(7, "rPos:%u => set initial price : %.2f",
1021 pos, ZSTD_fCost(sequencePrice));
1022 opt[pos].mlen = pos;
1023 opt[pos].off = offset;
1024 opt[pos].litlen = litlen;
1025 opt[pos].price = sequencePrice;
1026 } }
1027 last_pos = pos-1;
1028 }
1029 }
1030
1031 /* check further positions */
1032 for (cur = 1; cur <= last_pos; cur++) {
1033 const BYTE* const inr = ip + cur;
1034 assert(cur < ZSTD_OPT_NUM);
1035 DEBUGLOG(7, "cPos:%zi==rPos:%u", inr-istart, cur)
1036
1037 /* Fix current position with one literal if cheaper */
1038 { U32 const litlen = (opt[cur-1].mlen == 0) ? opt[cur-1].litlen + 1 : 1;
1039 int const price = opt[cur-1].price
1040 + ZSTD_rawLiteralsCost(ip+cur-1, 1, optStatePtr, optLevel)
1041 + ZSTD_litLengthPrice(litlen, optStatePtr, optLevel)
1042 - ZSTD_litLengthPrice(litlen-1, optStatePtr, optLevel);
1043 assert(price < 1000000000); /* overflow check */
1044 if (price <= opt[cur].price) {
1045 DEBUGLOG(7, "cPos:%zi==rPos:%u : better price (%.2f<=%.2f) using literal (ll==%u) (hist:%u,%u,%u)",
1046 inr-istart, cur, ZSTD_fCost(price), ZSTD_fCost(opt[cur].price), litlen,
1047 opt[cur-1].rep[0], opt[cur-1].rep[1], opt[cur-1].rep[2]);
1048 opt[cur].mlen = 0;
1049 opt[cur].off = 0;
1050 opt[cur].litlen = litlen;
1051 opt[cur].price = price;
1052 } else {
1053 DEBUGLOG(7, "cPos:%zi==rPos:%u : literal would cost more (%.2f>%.2f) (hist:%u,%u,%u)",
1054 inr-istart, cur, ZSTD_fCost(price), ZSTD_fCost(opt[cur].price),
1055 opt[cur].rep[0], opt[cur].rep[1], opt[cur].rep[2]);
1056 }
1057 }
1058
1059 /* Set the repcodes of the current position. We must do it here
1060 * because we rely on the repcodes of the 2nd to last sequence being
1061 * correct to set the next chunks repcodes during the backward
1062 * traversal.
1063 */
1064 ZSTD_STATIC_ASSERT(sizeof(opt[cur].rep) == sizeof(repcodes_t));
1065 assert(cur >= opt[cur].mlen);
1066 if (opt[cur].mlen != 0) {
1067 U32 const prev = cur - opt[cur].mlen;
1068 repcodes_t newReps = ZSTD_updateRep(opt[prev].rep, opt[cur].off, opt[cur].litlen==0);
1069 ZSTD_memcpy(opt[cur].rep, &newReps, sizeof(repcodes_t));
1070 } else {
1071 ZSTD_memcpy(opt[cur].rep, opt[cur - 1].rep, sizeof(repcodes_t));
1072 }
1073
1074 /* last match must start at a minimum distance of 8 from oend */
1075 if (inr > ilimit) continue;
1076
1077 if (cur == last_pos) break;
1078
1079 if ( (optLevel==0) /*static_test*/
1080 && (opt[cur+1].price <= opt[cur].price + (BITCOST_MULTIPLIER/2)) ) {
1081 DEBUGLOG(7, "move to next rPos:%u : price is <=", cur+1);
1082 continue; /* skip unpromising positions; about ~+6% speed, -0.01 ratio */
1083 }
1084
1085 { U32 const ll0 = (opt[cur].mlen != 0);
1086 U32 const litlen = (opt[cur].mlen == 0) ? opt[cur].litlen : 0;
1087 U32 const previousPrice = opt[cur].price;
1088 U32 const basePrice = previousPrice + ZSTD_litLengthPrice(0, optStatePtr, optLevel);
1089 U32 nbMatches = ZSTD_BtGetAllMatches(matches, ms, &nextToUpdate3, inr, iend, dictMode, opt[cur].rep, ll0, minMatch);
1090 U32 matchNb;
1091
1092 ZSTD_optLdm_processMatchCandidate(&optLdm, matches, &nbMatches,
1093 (U32)(inr-istart), (U32)(iend-inr));
1094
1095 if (!nbMatches) {
1096 DEBUGLOG(7, "rPos:%u : no match found", cur);
1097 continue;
1098 }
1099
1100 { U32 const maxML = matches[nbMatches-1].len;
1101 DEBUGLOG(7, "cPos:%zi==rPos:%u, found %u matches, of maxLength=%u",
1102 inr-istart, cur, nbMatches, maxML);
1103
1104 if ( (maxML > sufficient_len)
1105 || (cur + maxML >= ZSTD_OPT_NUM) ) {
1106 lastSequence.mlen = maxML;
1107 lastSequence.off = matches[nbMatches-1].off;
1108 lastSequence.litlen = litlen;
1109 cur -= (opt[cur].mlen==0) ? opt[cur].litlen : 0; /* last sequence is actually only literals, fix cur to last match - note : may underflow, in which case, it's first sequence, and it's okay */
1110 last_pos = cur + ZSTD_totalLen(lastSequence);
1111 if (cur > ZSTD_OPT_NUM) cur = 0; /* underflow => first match */
1112 goto _shortestPath;
1113 } }
1114
1115 /* set prices using matches found at position == cur */
1116 for (matchNb = 0; matchNb < nbMatches; matchNb++) {
1117 U32 const offset = matches[matchNb].off;
1118 U32 const lastML = matches[matchNb].len;
1119 U32 const startML = (matchNb>0) ? matches[matchNb-1].len+1 : minMatch;
1120 U32 mlen;
1121
1122 DEBUGLOG(7, "testing match %u => offCode=%4u, mlen=%2u, llen=%2u",
1123 matchNb, matches[matchNb].off, lastML, litlen);
1124
1125 for (mlen = lastML; mlen >= startML; mlen--) { /* scan downward */
1126 U32 const pos = cur + mlen;
1127 int const price = basePrice + ZSTD_getMatchPrice(offset, mlen, optStatePtr, optLevel);
1128
1129 if ((pos > last_pos) || (price < opt[pos].price)) {
1130 DEBUGLOG(7, "rPos:%u (ml=%2u) => new better price (%.2f<%.2f)",
1131 pos, mlen, ZSTD_fCost(price), ZSTD_fCost(opt[pos].price));
1132 while (last_pos < pos) { opt[last_pos+1].price = ZSTD_MAX_PRICE; last_pos++; } /* fill empty positions */
1133 opt[pos].mlen = mlen;
1134 opt[pos].off = offset;
1135 opt[pos].litlen = litlen;
1136 opt[pos].price = price;
1137 } else {
1138 DEBUGLOG(7, "rPos:%u (ml=%2u) => new price is worse (%.2f>=%.2f)",
1139 pos, mlen, ZSTD_fCost(price), ZSTD_fCost(opt[pos].price));
1140 if (optLevel==0) break; /* early update abort; gets ~+10% speed for about -0.01 ratio loss */
1141 }
1142 } } }
1143 } /* for (cur = 1; cur <= last_pos; cur++) */
1144
1145 lastSequence = opt[last_pos];
1146 cur = last_pos > ZSTD_totalLen(lastSequence) ? last_pos - ZSTD_totalLen(lastSequence) : 0; /* single sequence, and it starts before `ip` */
1147 assert(cur < ZSTD_OPT_NUM); /* control overflow*/
1148
1149 _shortestPath: /* cur, last_pos, best_mlen, best_off have to be set */
1150 assert(opt[0].mlen == 0);
1151
1152 /* Set the next chunk's repcodes based on the repcodes of the beginning
1153 * of the last match, and the last sequence. This avoids us having to
1154 * update them while traversing the sequences.
1155 */
1156 if (lastSequence.mlen != 0) {
1157 repcodes_t reps = ZSTD_updateRep(opt[cur].rep, lastSequence.off, lastSequence.litlen==0);
1158 ZSTD_memcpy(rep, &reps, sizeof(reps));
1159 } else {
1160 ZSTD_memcpy(rep, opt[cur].rep, sizeof(repcodes_t));
1161 }
1162
1163 { U32 const storeEnd = cur + 1;
1164 U32 storeStart = storeEnd;
1165 U32 seqPos = cur;
1166
1167 DEBUGLOG(6, "start reverse traversal (last_pos:%u, cur:%u)",
1168 last_pos, cur); (void)last_pos;
1169 assert(storeEnd < ZSTD_OPT_NUM);
1170 DEBUGLOG(6, "last sequence copied into pos=%u (llen=%u,mlen=%u,ofc=%u)",
1171 storeEnd, lastSequence.litlen, lastSequence.mlen, lastSequence.off);
1172 opt[storeEnd] = lastSequence;
1173 while (seqPos > 0) {
1174 U32 const backDist = ZSTD_totalLen(opt[seqPos]);
1175 storeStart--;
1176 DEBUGLOG(6, "sequence from rPos=%u copied into pos=%u (llen=%u,mlen=%u,ofc=%u)",
1177 seqPos, storeStart, opt[seqPos].litlen, opt[seqPos].mlen, opt[seqPos].off);
1178 opt[storeStart] = opt[seqPos];
1179 seqPos = (seqPos > backDist) ? seqPos - backDist : 0;
1180 }
1181
1182 /* save sequences */
1183 DEBUGLOG(6, "sending selected sequences into seqStore")
1184 { U32 storePos;
1185 for (storePos=storeStart; storePos <= storeEnd; storePos++) {
1186 U32 const llen = opt[storePos].litlen;
1187 U32 const mlen = opt[storePos].mlen;
1188 U32 const offCode = opt[storePos].off;
1189 U32 const advance = llen + mlen;
1190 DEBUGLOG(6, "considering seq starting at %zi, llen=%u, mlen=%u",
1191 anchor - istart, (unsigned)llen, (unsigned)mlen);
1192
1193 if (mlen==0) { /* only literals => must be last "sequence", actually starting a new stream of sequences */
1194 assert(storePos == storeEnd); /* must be last sequence */
1195 ip = anchor + llen; /* last "sequence" is a bunch of literals => don't progress anchor */
1196 continue; /* will finish */
1197 }
1198
1199 assert(anchor + llen <= iend);
1200 ZSTD_updateStats(optStatePtr, llen, anchor, offCode, mlen);
1201 ZSTD_storeSeq(seqStore, llen, anchor, iend, offCode, mlen-MINMATCH);
1202 anchor += advance;
1203 ip = anchor;
1204 } }
1205 ZSTD_setBasePrices(optStatePtr, optLevel);
1206 }
1207 } /* while (ip < ilimit) */
1208
1209 /* Return the last literals size */
1210 return (size_t)(iend - anchor);
1211 }
1212
1213
ZSTD_compressBlock_btopt(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize)1214 size_t ZSTD_compressBlock_btopt(
1215 ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
1216 const void* src, size_t srcSize)
1217 {
1218 DEBUGLOG(5, "ZSTD_compressBlock_btopt");
1219 return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 0 /*optLevel*/, ZSTD_noDict);
1220 }
1221
1222
1223 /* used in 2-pass strategy */
ZSTD_upscaleStat(unsigned * table,U32 lastEltIndex,int bonus)1224 static U32 ZSTD_upscaleStat(unsigned* table, U32 lastEltIndex, int bonus)
1225 {
1226 U32 s, sum=0;
1227 assert(ZSTD_FREQ_DIV+bonus >= 0);
1228 for (s=0; s<lastEltIndex+1; s++) {
1229 table[s] <<= ZSTD_FREQ_DIV+bonus;
1230 table[s]--;
1231 sum += table[s];
1232 }
1233 return sum;
1234 }
1235
1236 /* used in 2-pass strategy */
ZSTD_upscaleStats(optState_t * optPtr)1237 MEM_STATIC void ZSTD_upscaleStats(optState_t* optPtr)
1238 {
1239 if (ZSTD_compressedLiterals(optPtr))
1240 optPtr->litSum = ZSTD_upscaleStat(optPtr->litFreq, MaxLit, 0);
1241 optPtr->litLengthSum = ZSTD_upscaleStat(optPtr->litLengthFreq, MaxLL, 0);
1242 optPtr->matchLengthSum = ZSTD_upscaleStat(optPtr->matchLengthFreq, MaxML, 0);
1243 optPtr->offCodeSum = ZSTD_upscaleStat(optPtr->offCodeFreq, MaxOff, 0);
1244 }
1245
1246 /* ZSTD_initStats_ultra():
1247 * make a first compression pass, just to seed stats with more accurate starting values.
1248 * only works on first block, with no dictionary and no ldm.
1249 * this function cannot error, hence its contract must be respected.
1250 */
1251 static void
ZSTD_initStats_ultra(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize)1252 ZSTD_initStats_ultra(ZSTD_matchState_t* ms,
1253 seqStore_t* seqStore,
1254 U32 rep[ZSTD_REP_NUM],
1255 const void* src, size_t srcSize)
1256 {
1257 U32 tmpRep[ZSTD_REP_NUM]; /* updated rep codes will sink here */
1258 ZSTD_memcpy(tmpRep, rep, sizeof(tmpRep));
1259
1260 DEBUGLOG(4, "ZSTD_initStats_ultra (srcSize=%zu)", srcSize);
1261 assert(ms->opt.litLengthSum == 0); /* first block */
1262 assert(seqStore->sequences == seqStore->sequencesStart); /* no ldm */
1263 assert(ms->window.dictLimit == ms->window.lowLimit); /* no dictionary */
1264 assert(ms->window.dictLimit - ms->nextToUpdate <= 1); /* no prefix (note: intentional overflow, defined as 2-complement) */
1265
1266 ZSTD_compressBlock_opt_generic(ms, seqStore, tmpRep, src, srcSize, 2 /*optLevel*/, ZSTD_noDict); /* generate stats into ms->opt*/
1267
1268 /* invalidate first scan from history */
1269 ZSTD_resetSeqStore(seqStore);
1270 ms->window.base -= srcSize;
1271 ms->window.dictLimit += (U32)srcSize;
1272 ms->window.lowLimit = ms->window.dictLimit;
1273 ms->nextToUpdate = ms->window.dictLimit;
1274
1275 /* re-inforce weight of collected statistics */
1276 ZSTD_upscaleStats(&ms->opt);
1277 }
1278
ZSTD_compressBlock_btultra(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize)1279 size_t ZSTD_compressBlock_btultra(
1280 ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
1281 const void* src, size_t srcSize)
1282 {
1283 DEBUGLOG(5, "ZSTD_compressBlock_btultra (srcSize=%zu)", srcSize);
1284 return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /*optLevel*/, ZSTD_noDict);
1285 }
1286
ZSTD_compressBlock_btultra2(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize)1287 size_t ZSTD_compressBlock_btultra2(
1288 ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
1289 const void* src, size_t srcSize)
1290 {
1291 U32 const curr = (U32)((const BYTE*)src - ms->window.base);
1292 DEBUGLOG(5, "ZSTD_compressBlock_btultra2 (srcSize=%zu)", srcSize);
1293
1294 /* 2-pass strategy:
1295 * this strategy makes a first pass over first block to collect statistics
1296 * and seed next round's statistics with it.
1297 * After 1st pass, function forgets everything, and starts a new block.
1298 * Consequently, this can only work if no data has been previously loaded in tables,
1299 * aka, no dictionary, no prefix, no ldm preprocessing.
1300 * The compression ratio gain is generally small (~0.5% on first block),
1301 * the cost is 2x cpu time on first block. */
1302 assert(srcSize <= ZSTD_BLOCKSIZE_MAX);
1303 if ( (ms->opt.litLengthSum==0) /* first block */
1304 && (seqStore->sequences == seqStore->sequencesStart) /* no ldm */
1305 && (ms->window.dictLimit == ms->window.lowLimit) /* no dictionary */
1306 && (curr == ms->window.dictLimit) /* start of frame, nothing already loaded nor skipped */
1307 && (srcSize > ZSTD_PREDEF_THRESHOLD)
1308 ) {
1309 ZSTD_initStats_ultra(ms, seqStore, rep, src, srcSize);
1310 }
1311
1312 return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /*optLevel*/, ZSTD_noDict);
1313 }
1314
ZSTD_compressBlock_btopt_dictMatchState(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize)1315 size_t ZSTD_compressBlock_btopt_dictMatchState(
1316 ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
1317 const void* src, size_t srcSize)
1318 {
1319 return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 0 /*optLevel*/, ZSTD_dictMatchState);
1320 }
1321
ZSTD_compressBlock_btultra_dictMatchState(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize)1322 size_t ZSTD_compressBlock_btultra_dictMatchState(
1323 ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
1324 const void* src, size_t srcSize)
1325 {
1326 return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /*optLevel*/, ZSTD_dictMatchState);
1327 }
1328
ZSTD_compressBlock_btopt_extDict(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize)1329 size_t ZSTD_compressBlock_btopt_extDict(
1330 ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
1331 const void* src, size_t srcSize)
1332 {
1333 return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 0 /*optLevel*/, ZSTD_extDict);
1334 }
1335
ZSTD_compressBlock_btultra_extDict(ZSTD_matchState_t * ms,seqStore_t * seqStore,U32 rep[ZSTD_REP_NUM],const void * src,size_t srcSize)1336 size_t ZSTD_compressBlock_btultra_extDict(
1337 ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
1338 const void* src, size_t srcSize)
1339 {
1340 return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /*optLevel*/, ZSTD_extDict);
1341 }
1342
1343 /* note : no btultra2 variant for extDict nor dictMatchState,
1344 * because btultra2 is not meant to work with dictionaries
1345 * and is only specific for the first block (no prefix) */
1346