zstd/compress/zstd_opt.c

292  * Provides the cost of the match part (offset + matchLength) of a sequence
299                    U32 const matchLength,
305     U32 const mlBase = matchLength - MINMATCH;
306     assert(matchLength >= MINMATCH);
323     DEBUGLOG(8, "ZSTD_getMatchPrice(ml:%u) = %u", matchLength, price);
331                              U32 offsetCode, U32 matchLength)
355     {   U32 const mlBase = matchLength - MINMATCH;
460         size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger);   /* guaranteed minimum nb of common bytes */
484         if (!extDict || (matchIndex+matchLength >= dictLimit)) {
485             assert(matchIndex+matchLength >= dictLimit);   /* might be wrong if actually extDict */
487             matchLength += ZSTD_count(ip+matchLength, match+matchLength, iend);
490             matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iend, dictEnd, prefixStart);
491             if (matchIndex+matchLength >= dictLimit)
492                 match = base + matchIndex;   /* to prepare for next usage of match[matchLength] */
495         if (matchLength > bestLength) {
496             bestLength = matchLength;
497             if (matchLength > matchEndIdx - matchIndex)
498                 matchEndIdx = matchIndex + (U32)matchLength;
501         if (ip+matchLength == iend) {   /* equal : no way to know if inf or sup */
505         if (match[matchLength] < ip[matchLength]) {  /* necessarily within buffer */
508             commonLengthSmaller = matchLength;    /* all smaller will now have at least this guaranteed common length */
515             commonLengthLarger = matchLength;
692         size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger);   /* guaranteed minimum nb of common bytes */
695         if ((dictMode == ZSTD_noDict) || (dictMode == ZSTD_dictMatchState) || (matchIndex+matchLength >= dictLimit)) {
696             assert(matchIndex+matchLength >= dictLimit);  /* ensure the condition is correct when !extDict */
698             if (matchIndex >= dictLimit) assert(memcmp(match, ip, matchLength) == 0);  /* ensure early section of match is equal as expected */
699             matchLength += ZSTD_count(ip+matchLength, match+matchLength, iLimit);
702             assert(memcmp(match, ip, matchLength) == 0);  /* ensure early section of match is equal as expected */
703             matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iLimit, dictEnd, prefixStart);
704             if (matchIndex+matchLength >= dictLimit)
705                 match = base + matchIndex;   /* prepare for match[matchLength] read */
708         if (matchLength > bestLength) {
710                     (U32)matchLength, curr - matchIndex, STORE_OFFSET(curr - matchIndex));
712             if (matchLength > matchEndIdx - matchIndex)
713                 matchEndIdx = matchIndex + (U32)matchLength;
714             bestLength = matchLength;
716             matches[mnum].len = (U32)matchLength;
718             if ( (matchLength > ZSTD_OPT_NUM)
719                | (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */) {
724         if (match[matchLength] < ip[matchLength]) {
727             commonLengthSmaller = matchLength;    /* all smaller will now have at least this guaranteed common length */
733             commonLengthLarger = matchLength;
749             size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger);   /* guaranteed minimum nb of common bytes */
751             matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iLimit, dmsEnd, prefixStart);
752             if (dictMatchIndex+matchLength >= dmsHighLimit)
753                 match = base + dictMatchIndex + dmsIndexDelta;   /* to prepare for next usage of match[matchLength] */
755             if (matchLength > bestLength) {
758                         (U32)matchLength, curr - matchIndex, STORE_OFFSET(curr - matchIndex));
759                 if (matchLength > matchEndIdx - matchIndex)
760                     matchEndIdx = matchIndex + (U32)matchLength;
761                 bestLength = matchLength;
763                 matches[mnum].len = (U32)matchLength;
765                 if ( (matchLength > ZSTD_OPT_NUM)
766                    | (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */) {
771             if (match[matchLength] < ip[matchLength]) {
772                 commonLengthSmaller = matchLength;    /* all smaller will now have at least this guaranteed common length */
776                 commonLengthLarger = matchLength;
886         if (currPos >= currSeq.litLength + currSeq.matchLength) {
887             currPos -= currSeq.litLength + currSeq.matchLength;
918     /* Calculate appropriate bytes left in matchLength and litLength
921     assert(optLdm->seqStore.posInSequence <= currSeq.litLength + currSeq.matchLength);
927             currSeq.matchLength - ((U32)optLdm->seqStore.posInSequence - currSeq.litLength) :
928             currSeq.matchLength;
963     /* Note: ZSTD_match_t actually contains offCode and matchLength (before subtracting MINMATCH) */
975         DEBUGLOG(6, "ZSTD_optLdm_maybeAddMatch(): Adding ldm candidate match (offCode: %u matchLength %u) at block position=%u",