diff options
Diffstat (limited to 'lib/zstd/compress/zstd_opt.c')
| -rw-r--r-- | lib/zstd/compress/zstd_opt.c | 402 |
1 files changed, 245 insertions, 157 deletions
diff --git a/lib/zstd/compress/zstd_opt.c b/lib/zstd/compress/zstd_opt.c index dfc55e3e8119..fd82acfda62f 100644 --- a/lib/zstd/compress/zstd_opt.c +++ b/lib/zstd/compress/zstd_opt.c @@ -8,25 +8,12 @@ * You may select, at your option, one of the above-listed licenses. */ -/* - * Disable inlining for the optimal parser for the kernel build. - * It is unlikely to be used in the kernel, and where it is used - * latency shouldn't matter because it is very slow to begin with. - * We prefer a ~180KB binary size win over faster optimal parsing. - * - * TODO(https://github.com/facebook/zstd/issues/2862): - * Improve the code size of the optimal parser in general, so we - * don't need this hack for the kernel build. - */ -#define ZSTD_NO_INLINE 1 - #include "zstd_compress_internal.h" #include "hist.h" #include "zstd_opt.h" #define ZSTD_LITFREQ_ADD 2 /* scaling factor for litFreq, so that frequencies adapt faster to new stats */ -#define ZSTD_FREQ_DIV 4 /* log factor when using previous stats to init next stats */ #define ZSTD_MAX_PRICE (1<<30) #define ZSTD_PREDEF_THRESHOLD 1024 /* if srcSize < ZSTD_PREDEF_THRESHOLD, symbols' cost is assumed static, directly determined by pre-defined distributions */ @@ -36,11 +23,11 @@ * Price functions for optimal parser ***************************************/ -#if 0 /* approximation at bit level */ +#if 0 /* approximation at bit level (for tests) */ # define BITCOST_ACCURACY 0 # define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY) -# define WEIGHT(stat) ((void)opt, ZSTD_bitWeight(stat)) -#elif 0 /* fractional bit accuracy */ +# define WEIGHT(stat, opt) ((void)opt, ZSTD_bitWeight(stat)) +#elif 0 /* fractional bit accuracy (for tests) */ # define BITCOST_ACCURACY 8 # define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY) # define WEIGHT(stat,opt) ((void)opt, ZSTD_fracWeight(stat)) @@ -78,7 +65,7 @@ MEM_STATIC double ZSTD_fCost(U32 price) static int ZSTD_compressedLiterals(optState_t const* const optPtr) { - return optPtr->literalCompressionMode != ZSTD_lcm_uncompressed; + return optPtr->literalCompressionMode != ZSTD_ps_disable; } static void ZSTD_setBasePrices(optState_t* optPtr, int optLevel) @@ -91,25 +78,46 @@ static void ZSTD_setBasePrices(optState_t* optPtr, int optLevel) } -/* ZSTD_downscaleStat() : - * reduce all elements in table by a factor 2^(ZSTD_FREQ_DIV+malus) - * return the resulting sum of elements */ -static U32 ZSTD_downscaleStat(unsigned* table, U32 lastEltIndex, int malus) +static U32 sum_u32(const unsigned table[], size_t nbElts) +{ + size_t n; + U32 total = 0; + for (n=0; n<nbElts; n++) { + total += table[n]; + } + return total; +} + +static U32 ZSTD_downscaleStats(unsigned* table, U32 lastEltIndex, U32 shift) { U32 s, sum=0; - DEBUGLOG(5, "ZSTD_downscaleStat (nbElts=%u)", (unsigned)lastEltIndex+1); - assert(ZSTD_FREQ_DIV+malus > 0 && ZSTD_FREQ_DIV+malus < 31); + DEBUGLOG(5, "ZSTD_downscaleStats (nbElts=%u, shift=%u)", (unsigned)lastEltIndex+1, (unsigned)shift); + assert(shift < 30); for (s=0; s<lastEltIndex+1; s++) { - table[s] = 1 + (table[s] >> (ZSTD_FREQ_DIV+malus)); + table[s] = 1 + (table[s] >> shift); sum += table[s]; } return sum; } +/* ZSTD_scaleStats() : + * reduce all elements in table is sum too large + * return the resulting sum of elements */ +static U32 ZSTD_scaleStats(unsigned* table, U32 lastEltIndex, U32 logTarget) +{ + U32 const prevsum = sum_u32(table, lastEltIndex+1); + U32 const factor = prevsum >> logTarget; + DEBUGLOG(5, "ZSTD_scaleStats (nbElts=%u, target=%u)", (unsigned)lastEltIndex+1, (unsigned)logTarget); + assert(logTarget < 30); + if (factor <= 1) return prevsum; + return ZSTD_downscaleStats(table, lastEltIndex, ZSTD_highbit32(factor)); +} + /* ZSTD_rescaleFreqs() : * if first block (detected by optPtr->litLengthSum == 0) : init statistics * take hints from dictionary if there is one - * or init from zero, using src for literals stats, or flat 1 for match symbols + * and init from zero if there is none, + * using src for literals stats, and baseline stats for sequence symbols * otherwise downscale existing stats, to be used as seed for next block. */ static void @@ -138,7 +146,7 @@ ZSTD_rescaleFreqs(optState_t* const optPtr, optPtr->litSum = 0; for (lit=0; lit<=MaxLit; lit++) { U32 const scaleLog = 11; /* scale to 2K */ - U32 const bitCost = HUF_getNbBits(optPtr->symbolCosts->huf.CTable, lit); + U32 const bitCost = HUF_getNbBitsFromCTable(optPtr->symbolCosts->huf.CTable, lit); assert(bitCost <= scaleLog); optPtr->litFreq[lit] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/; optPtr->litSum += optPtr->litFreq[lit]; @@ -186,14 +194,19 @@ ZSTD_rescaleFreqs(optState_t* const optPtr, if (compressedLiterals) { unsigned lit = MaxLit; HIST_count_simple(optPtr->litFreq, &lit, src, srcSize); /* use raw first block to init statistics */ - optPtr->litSum = ZSTD_downscaleStat(optPtr->litFreq, MaxLit, 1); + optPtr->litSum = ZSTD_downscaleStats(optPtr->litFreq, MaxLit, 8); } - { unsigned ll; - for (ll=0; ll<=MaxLL; ll++) - optPtr->litLengthFreq[ll] = 1; + { unsigned const baseLLfreqs[MaxLL+1] = { + 4, 2, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1 + }; + ZSTD_memcpy(optPtr->litLengthFreq, baseLLfreqs, sizeof(baseLLfreqs)); + optPtr->litLengthSum = sum_u32(baseLLfreqs, MaxLL+1); } - optPtr->litLengthSum = MaxLL+1; { unsigned ml; for (ml=0; ml<=MaxML; ml++) @@ -201,21 +214,26 @@ ZSTD_rescaleFreqs(optState_t* const optPtr, } optPtr->matchLengthSum = MaxML+1; - { unsigned of; - for (of=0; of<=MaxOff; of++) - optPtr->offCodeFreq[of] = 1; + { unsigned const baseOFCfreqs[MaxOff+1] = { + 6, 2, 1, 1, 2, 3, 4, 4, + 4, 3, 2, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1 + }; + ZSTD_memcpy(optPtr->offCodeFreq, baseOFCfreqs, sizeof(baseOFCfreqs)); + optPtr->offCodeSum = sum_u32(baseOFCfreqs, MaxOff+1); } - optPtr->offCodeSum = MaxOff+1; + } } else { /* new block : re-use previous statistics, scaled down */ if (compressedLiterals) - optPtr->litSum = ZSTD_downscaleStat(optPtr->litFreq, MaxLit, 1); - optPtr->litLengthSum = ZSTD_downscaleStat(optPtr->litLengthFreq, MaxLL, 0); - optPtr->matchLengthSum = ZSTD_downscaleStat(optPtr->matchLengthFreq, MaxML, 0); - optPtr->offCodeSum = ZSTD_downscaleStat(optPtr->offCodeFreq, MaxOff, 0); + optPtr->litSum = ZSTD_scaleStats(optPtr->litFreq, MaxLit, 12); + optPtr->litLengthSum = ZSTD_scaleStats(optPtr->litLengthFreq, MaxLL, 11); + optPtr->matchLengthSum = ZSTD_scaleStats(optPtr->matchLengthFreq, MaxML, 11); + optPtr->offCodeSum = ZSTD_scaleStats(optPtr->offCodeFreq, MaxOff, 11); } ZSTD_setBasePrices(optPtr, optLevel); @@ -251,7 +269,16 @@ static U32 ZSTD_rawLiteralsCost(const BYTE* const literals, U32 const litLength, * cost of literalLength symbol */ static U32 ZSTD_litLengthPrice(U32 const litLength, const optState_t* const optPtr, int optLevel) { - if (optPtr->priceType == zop_predef) return WEIGHT(litLength, optLevel); + assert(litLength <= ZSTD_BLOCKSIZE_MAX); + if (optPtr->priceType == zop_predef) + return WEIGHT(litLength, optLevel); + /* We can't compute the litLength price for sizes >= ZSTD_BLOCKSIZE_MAX + * because it isn't representable in the zstd format. So instead just + * call it 1 bit more than ZSTD_BLOCKSIZE_MAX - 1. In this case the block + * would be all literals. + */ + if (litLength == ZSTD_BLOCKSIZE_MAX) + return BITCOST_MULTIPLIER + ZSTD_litLengthPrice(ZSTD_BLOCKSIZE_MAX - 1, optPtr, optLevel); /* dynamic statistics */ { U32 const llCode = ZSTD_LLcode(litLength); @@ -264,15 +291,17 @@ static U32 ZSTD_litLengthPrice(U32 const litLength, const optState_t* const optP /* ZSTD_getMatchPrice() : * Provides the cost of the match part (offset + matchLength) of a sequence * Must be combined with ZSTD_fullLiteralsCost() to get the full cost of a sequence. - * optLevel: when <2, favors small offset for decompression speed (improved cache efficiency) */ + * @offcode : expects a scale where 0,1,2 are repcodes 1-3, and 3+ are real_offsets+2 + * @optLevel: when <2, favors small offset for decompression speed (improved cache efficiency) + */ FORCE_INLINE_TEMPLATE U32 -ZSTD_getMatchPrice(U32 const offset, +ZSTD_getMatchPrice(U32 const offcode, U32 const matchLength, const optState_t* const optPtr, int const optLevel) { U32 price; - U32 const offCode = ZSTD_highbit32(offset+1); + U32 const offCode = ZSTD_highbit32(STORED_TO_OFFBASE(offcode)); U32 const mlBase = matchLength - MINMATCH; assert(matchLength >= MINMATCH); @@ -315,8 +344,8 @@ static void ZSTD_updateStats(optState_t* const optPtr, optPtr->litLengthSum++; } - /* match offset code (0-2=>repCode; 3+=>offset+2) */ - { U32 const offCode = ZSTD_highbit32(offsetCode+1); + /* offset code : expected to follow storeSeq() numeric representation */ + { U32 const offCode = ZSTD_highbit32(STORED_TO_OFFBASE(offsetCode)); assert(offCode <= MaxOff); optPtr->offCodeFreq[offCode]++; optPtr->offCodeSum++; @@ -350,7 +379,7 @@ MEM_STATIC U32 ZSTD_readMINMATCH(const void* memPtr, U32 length) /* Update hashTable3 up to ip (excluded) Assumption : always within prefix (i.e. not within extDict) */ -static U32 ZSTD_insertAndFindFirstIndexHash3 (ZSTD_matchState_t* ms, +static U32 ZSTD_insertAndFindFirstIndexHash3 (const ZSTD_matchState_t* ms, U32* nextToUpdate3, const BYTE* const ip) { @@ -376,11 +405,13 @@ static U32 ZSTD_insertAndFindFirstIndexHash3 (ZSTD_matchState_t* ms, * Binary Tree search ***************************************/ /* ZSTD_insertBt1() : add one or multiple positions to tree. - * ip : assumed <= iend-8 . + * @param ip assumed <= iend-8 . + * @param target The target of ZSTD_updateTree_internal() - we are filling to this position * @return : nb of positions added */ static U32 ZSTD_insertBt1( - ZSTD_matchState_t* ms, + const ZSTD_matchState_t* ms, const BYTE* const ip, const BYTE* const iend, + U32 const target, U32 const mls, const int extDict) { const ZSTD_compressionParameters* const cParams = &ms->cParams; @@ -403,7 +434,10 @@ static U32 ZSTD_insertBt1( U32* smallerPtr = bt + 2*(curr&btMask); U32* largerPtr = smallerPtr + 1; U32 dummy32; /* to be nullified at the end */ - U32 const windowLow = ms->window.lowLimit; + /* windowLow is based on target because + * we only need positions that will be in the window at the end of the tree update. + */ + U32 const windowLow = ZSTD_getLowestMatchIndex(ms, target, cParams->windowLog); U32 matchEndIdx = curr+8+1; size_t bestLength = 8; U32 nbCompares = 1U << cParams->searchLog; @@ -416,6 +450,7 @@ static U32 ZSTD_insertBt1( DEBUGLOG(8, "ZSTD_insertBt1 (%u)", curr); + assert(curr <= target); assert(ip <= iend-8); /* required for h calculation */ hashTable[h] = curr; /* Update Hash Table */ @@ -504,7 +539,7 @@ void ZSTD_updateTree_internal( idx, target, dictMode); while(idx < target) { - U32 const forward = ZSTD_insertBt1(ms, base+idx, iend, mls, dictMode == ZSTD_extDict); + U32 const forward = ZSTD_insertBt1(ms, base+idx, iend, target, mls, dictMode == ZSTD_extDict); assert(idx < (U32)(idx + forward)); idx += forward; } @@ -609,7 +644,7 @@ U32 ZSTD_insertBtAndGetAllMatches ( DEBUGLOG(8, "found repCode %u (ll0:%u, offset:%u) of length %u", repCode, ll0, repOffset, repLen); bestLength = repLen; - matches[mnum].off = repCode - ll0; + matches[mnum].off = STORE_REPCODE(repCode - ll0 + 1); /* expect value between 1 and 3 */ matches[mnum].len = (U32)repLen; mnum++; if ( (repLen > sufficient_len) @@ -638,7 +673,7 @@ U32 ZSTD_insertBtAndGetAllMatches ( bestLength = mlen; assert(curr > matchIndex3); assert(mnum==0); /* no prior solution */ - matches[0].off = (curr - matchIndex3) + ZSTD_REP_MOVE; + matches[0].off = STORE_OFFSET(curr - matchIndex3); matches[0].len = (U32)mlen; mnum = 1; if ( (mlen > sufficient_len) | @@ -647,7 +682,7 @@ U32 ZSTD_insertBtAndGetAllMatches ( return 1; } } } /* no dictMatchState lookup: dicts don't have a populated HC3 table */ - } + } /* if (mls == 3) */ hashTable[h] = curr; /* Update Hash Table */ @@ -672,20 +707,19 @@ U32 ZSTD_insertBtAndGetAllMatches ( if (matchLength > bestLength) { DEBUGLOG(8, "found match of length %u at distance %u (offCode=%u)", - (U32)matchLength, curr - matchIndex, curr - matchIndex + ZSTD_REP_MOVE); + (U32)matchLength, curr - matchIndex, STORE_OFFSET(curr - matchIndex)); assert(matchEndIdx > matchIndex); if (matchLength > matchEndIdx - matchIndex) matchEndIdx = matchIndex + (U32)matchLength; bestLength = matchLength; - matches[mnum].off = (curr - matchIndex) + ZSTD_REP_MOVE; + matches[mnum].off = STORE_OFFSET(curr - matchIndex); matches[mnum].len = (U32)matchLength; mnum++; if ( (matchLength > ZSTD_OPT_NUM) | (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */) { if (dictMode == ZSTD_dictMatchState) nbCompares = 0; /* break should also skip searching dms */ break; /* drop, to preserve bt consistency (miss a little bit of compression) */ - } - } + } } if (match[matchLength] < ip[matchLength]) { /* match smaller than current */ @@ -721,18 +755,17 @@ U32 ZSTD_insertBtAndGetAllMatches ( if (matchLength > bestLength) { matchIndex = dictMatchIndex + dmsIndexDelta; DEBUGLOG(8, "found dms match of length %u at distance %u (offCode=%u)", - (U32)matchLength, curr - matchIndex, curr - matchIndex + ZSTD_REP_MOVE); + (U32)matchLength, curr - matchIndex, STORE_OFFSET(curr - matchIndex)); if (matchLength > matchEndIdx - matchIndex) matchEndIdx = matchIndex + (U32)matchLength; bestLength = matchLength; - matches[mnum].off = (curr - matchIndex) + ZSTD_REP_MOVE; + matches[mnum].off = STORE_OFFSET(curr - matchIndex); matches[mnum].len = (U32)matchLength; mnum++; if ( (matchLength > ZSTD_OPT_NUM) | (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */) { break; /* drop, to guarantee consistency (miss a little bit of compression) */ - } - } + } } if (dictMatchIndex <= dmsBtLow) { break; } /* beyond tree size, stop the search */ if (match[matchLength] < ip[matchLength]) { @@ -742,39 +775,91 @@ U32 ZSTD_insertBtAndGetAllMatches ( /* match is larger than current */ commonLengthLarger = matchLength; dictMatchIndex = nextPtr[0]; - } - } - } + } } } /* if (dictMode == ZSTD_dictMatchState) */ assert(matchEndIdx > curr+8); ms->nextToUpdate = matchEndIdx - 8; /* skip repetitive patterns */ return mnum; } - -FORCE_INLINE_TEMPLATE U32 ZSTD_BtGetAllMatches ( - ZSTD_match_t* matches, /* store result (match found, increasing size) in this table */ - 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) +typedef U32 (*ZSTD_getAllMatchesFn)( + ZSTD_match_t*, + ZSTD_matchState_t*, + U32*, + const BYTE*, + const BYTE*, + const U32 rep[ZSTD_REP_NUM], + U32 const ll0, + U32 const lengthToBeat); + +FORCE_INLINE_TEMPLATE U32 ZSTD_btGetAllMatches_internal( + ZSTD_match_t* matches, + ZSTD_matchState_t* ms, + U32* nextToUpdate3, + const BYTE* ip, + const BYTE* const iHighLimit, + const U32 rep[ZSTD_REP_NUM], + U32 const ll0, + U32 const lengthToBeat, + const ZSTD_dictMode_e dictMode, + const U32 mls) { - const ZSTD_compressionParameters* const cParams = &ms->cParams; - U32 const matchLengthSearch = cParams->minMatch; - DEBUGLOG(8, "ZSTD_BtGetAllMatches"); - if (ip < ms->window.base + ms->nextToUpdate) return 0; /* skipped area */ - ZSTD_updateTree_internal(ms, ip, iHighLimit, matchLengthSearch, dictMode); - switch(matchLengthSearch) - { - case 3 : return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, 3); - default : - case 4 : return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, 4); - case 5 : return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, 5); - case 7 : - case 6 : return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, 6); + assert(BOUNDED(3, ms->cParams.minMatch, 6) == mls); + DEBUGLOG(8, "ZSTD_BtGetAllMatches(dictMode=%d, mls=%u)", (int)dictMode, mls); + if (ip < ms->window.base + ms->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree_internal(ms, ip, iHighLimit, mls, dictMode); + return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, mls); +} + +#define ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, mls) ZSTD_btGetAllMatches_##dictMode##_##mls + +#define GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, mls) \ + static U32 ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, mls)( \ + ZSTD_match_t* matches, \ + ZSTD_matchState_t* ms, \ + U32* nextToUpdate3, \ + const BYTE* ip, \ + const BYTE* const iHighLimit, \ + const U32 rep[ZSTD_REP_NUM], \ + U32 const ll0, \ + U32 const lengthToBeat) \ + { \ + return ZSTD_btGetAllMatches_internal( \ + matches, ms, nextToUpdate3, ip, iHighLimit, \ + rep, ll0, lengthToBeat, ZSTD_##dictMode, mls); \ + } + +#define GEN_ZSTD_BT_GET_ALL_MATCHES(dictMode) \ + GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, 3) \ + GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, 4) \ + GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, 5) \ + GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, 6) + +GEN_ZSTD_BT_GET_ALL_MATCHES(noDict) +GEN_ZSTD_BT_GET_ALL_MATCHES(extDict) +GEN_ZSTD_BT_GET_ALL_MATCHES(dictMatchState) + +#define ZSTD_BT_GET_ALL_MATCHES_ARRAY(dictMode) \ + { \ + ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, 3), \ + ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, 4), \ + ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, 5), \ + ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, 6) \ } + +static ZSTD_getAllMatchesFn +ZSTD_selectBtGetAllMatches(ZSTD_matchState_t const* ms, ZSTD_dictMode_e const dictMode) +{ + ZSTD_getAllMatchesFn const getAllMatchesFns[3][4] = { + ZSTD_BT_GET_ALL_MATCHES_ARRAY(noDict), + ZSTD_BT_GET_ALL_MATCHES_ARRAY(extDict), + ZSTD_BT_GET_ALL_MATCHES_ARRAY(dictMatchState) + }; + U32 const mls = BOUNDED(3, ms->cParams.minMatch, 6); + assert((U32)dictMode < 3); + assert(mls - 3 < 4); + return getAllMatchesFns[(int)dictMode][mls - 3]; } /* *********************** @@ -783,16 +868,18 @@ FORCE_INLINE_TEMPLATE U32 ZSTD_BtGetAllMatches ( /* Struct containing info needed to make decision about ldm inclusion */ typedef struct { - rawSeqStore_t seqStore; /* External match candidates store for this block */ - U32 startPosInBlock; /* Start position of the current match candidate */ - U32 endPosInBlock; /* End position of the current match candidate */ - U32 offset; /* Offset of the match candidate */ + rawSeqStore_t seqStore; /* External match candidates store for this block */ + U32 startPosInBlock; /* Start position of the current match candidate */ + U32 endPosInBlock; /* End position of the current match candidate */ + U32 offset; /* Offset of the match candidate */ } ZSTD_optLdm_t; /* ZSTD_optLdm_skipRawSeqStoreBytes(): - * Moves forward in rawSeqStore by nbBytes, which will update the fields 'pos' and 'posInSequence'. + * Moves forward in @rawSeqStore by @nbBytes, + * which will update the fields 'pos' and 'posInSequence'. */ -static void ZSTD_optLdm_skipRawSeqStoreBytes(rawSeqStore_t* rawSeqStore, size_t nbBytes) { +static void ZSTD_optLdm_skipRawSeqStoreBytes(rawSeqStore_t* rawSeqStore, size_t nbBytes) +{ U32 currPos = (U32)(rawSeqStore->posInSequence + nbBytes); while (currPos && rawSeqStore->pos < rawSeqStore->size) { rawSeq currSeq = rawSeqStore->seq[rawSeqStore->pos]; @@ -813,8 +900,10 @@ static void ZSTD_optLdm_skipRawSeqStoreBytes(rawSeqStore_t* rawSeqStore, size_t * Calculates the beginning and end of the next match in the current block. * Updates 'pos' and 'posInSequence' of the ldmSeqStore. */ -static void ZSTD_opt_getNextMatchAndUpdateSeqStore(ZSTD_optLdm_t* optLdm, U32 currPosInBlock, - U32 blockBytesRemaining) { +static void +ZSTD_opt_getNextMatchAndUpdateSeqStore(ZSTD_optLdm_t* optLdm, U32 currPosInBlock, + U32 blockBytesRemaining) +{ rawSeq currSeq; U32 currBlockEndPos; U32 literalsBytesRemaining; @@ -826,8 +915,8 @@ static void ZSTD_opt_getNextMatchAndUpdateSeqStore(ZSTD_optLdm_t* optLdm, U32 cu optLdm->endPosInBlock = UINT_MAX; return; } - /* Calculate appropriate bytes left in matchLength and litLength after adjusting - based on ldmSeqStore->posInSequence */ + /* Calculate appropriate bytes left in matchLength and litLength + * after adjusting based on ldmSeqStore->posInSequence */ currSeq = optLdm->seqStore.seq[optLdm->seqStore.pos]; assert(optLdm->seqStore.posInSequence <= currSeq.litLength + currSeq.matchLength); currBlockEndPos = currPosInBlock + blockBytesRemaining; @@ -863,15 +952,16 @@ static void ZSTD_opt_getNextMatchAndUpdateSeqStore(ZSTD_optLdm_t* optLdm, U32 cu } /* ZSTD_optLdm_maybeAddMatch(): - * Adds a match if it's long enough, based on it's 'matchStartPosInBlock' - * and 'matchEndPosInBlock', into 'matches'. Maintains the correct ordering of 'matches' + * Adds a match if it's long enough, + * based on it's 'matchStartPosInBlock' and 'matchEndPosInBlock', + * into 'matches'. Maintains the correct ordering of 'matches'. */ static void ZSTD_optLdm_maybeAddMatch(ZSTD_match_t* matches, U32* nbMatches, - ZSTD_optLdm_t* optLdm, U32 currPosInBlock) { - U32 posDiff = currPosInBlock - optLdm->startPosInBlock; + const ZSTD_optLdm_t* optLdm, U32 currPosInBlock) +{ + U32 const posDiff = currPosInBlock - optLdm->startPosInBlock; /* Note: ZSTD_match_t actually contains offCode and matchLength (before subtracting MINMATCH) */ - U32 candidateMatchLength = optLdm->endPosInBlock - optLdm->startPosInBlock - posDiff; - U32 candidateOffCode = optLdm->offset + ZSTD_REP_MOVE; + U32 const candidateMatchLength = optLdm->endPosInBlock - optLdm->startPosInBlock - posDiff; /* Ensure that current block position is not outside of the match */ if (currPosInBlock < optLdm->startPosInBlock @@ -881,6 +971,7 @@ static void ZSTD_optLdm_maybeAddMatch(ZSTD_match_t* matches, U32* nbMatches, } if (*nbMatches == 0 || ((candidateMatchLength > matches[*nbMatches-1].len) && *nbMatches < ZSTD_OPT_NUM)) { + U32 const candidateOffCode = STORE_OFFSET(optLdm->offset); DEBUGLOG(6, "ZSTD_optLdm_maybeAddMatch(): Adding ldm candidate match (offCode: %u matchLength %u) at block position=%u", candidateOffCode, candidateMatchLength, currPosInBlock); matches[*nbMatches].len = candidateMatchLength; @@ -892,8 +983,11 @@ static void ZSTD_optLdm_maybeAddMatch(ZSTD_match_t* matches, U32* nbMatches, /* ZSTD_optLdm_processMatchCandidate(): * Wrapper function to update ldm seq store and call ldm functions as necessary. */ -static void ZSTD_optLdm_processMatchCandidate(ZSTD_optLdm_t* optLdm, ZSTD_match_t* matches, U32* nbMatches, - U32 currPosInBlock, U32 remainingBytes) { +static void +ZSTD_optLdm_processMatchCandidate(ZSTD_optLdm_t* optLdm, + ZSTD_match_t* matches, U32* nbMatches, + U32 currPosInBlock, U32 remainingBytes) +{ if (optLdm->seqStore.size == 0 || optLdm->seqStore.pos >= optLdm->seqStore.size) { return; } @@ -904,19 +998,19 @@ static void ZSTD_optLdm_processMatchCandidate(ZSTD_optLdm_t* optLdm, ZSTD_match_ * at the end of a match from the ldm seq store, and will often be some bytes * over beyond matchEndPosInBlock. As such, we need to correct for these "overshoots" */ - U32 posOvershoot = currPosInBlock - optLdm->endPosInBlock; + U32 const posOvershoot = currPosInBlock - optLdm->endPosInBlock; ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, posOvershoot); - } + } ZSTD_opt_getNextMatchAndUpdateSeqStore(optLdm, currPosInBlock, remainingBytes); } ZSTD_optLdm_maybeAddMatch(matches, nbMatches, optLdm, currPosInBlock); } + /*-******************************* * Optimal parser *********************************/ - static U32 ZSTD_totalLen(ZSTD_optimal_t sol) { return sol.litlen + sol.mlen; @@ -957,6 +1051,8 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, const BYTE* const prefixStart = base + ms->window.dictLimit; const ZSTD_compressionParameters* const cParams = &ms->cParams; + ZSTD_getAllMatchesFn getAllMatches = ZSTD_selectBtGetAllMatches(ms, dictMode); + U32 const sufficient_len = MIN(cParams->targetLength, ZSTD_OPT_NUM -1); U32 const minMatch = (cParams->minMatch == 3) ? 3 : 4; U32 nextToUpdate3 = ms->nextToUpdate; @@ -984,7 +1080,7 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, /* find first match */ { U32 const litlen = (U32)(ip - anchor); U32 const ll0 = !litlen; - U32 nbMatches = ZSTD_BtGetAllMatches(matches, ms, &nextToUpdate3, ip, iend, dictMode, rep, ll0, minMatch); + U32 nbMatches = getAllMatches(matches, ms, &nextToUpdate3, ip, iend, rep, ll0, minMatch); ZSTD_optLdm_processMatchCandidate(&optLdm, matches, &nbMatches, (U32)(ip-istart), (U32)(iend - ip)); if (!nbMatches) { ip++; continue; } @@ -998,18 +1094,18 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, * in every price. We include the literal length to avoid negative * prices when we subtract the previous literal length. */ - opt[0].price = ZSTD_litLengthPrice(litlen, optStatePtr, optLevel); + opt[0].price = (int)ZSTD_litLengthPrice(litlen, optStatePtr, optLevel); /* large match -> immediate encoding */ { U32 const maxML = matches[nbMatches-1].len; - U32 const maxOffset = matches[nbMatches-1].off; + U32 const maxOffcode = matches[nbMatches-1].off; DEBUGLOG(6, "found %u matches of maxLength=%u and maxOffCode=%u at cPos=%u => start new series", - nbMatches, maxML, maxOffset, (U32)(ip-prefixStart)); + nbMatches, maxML, maxOffcode, (U32)(ip-prefixStart)); if (maxML > sufficient_len) { lastSequence.litlen = litlen; lastSequence.mlen = maxML; - lastSequence.off = maxOffset; + lastSequence.off = maxOffcode; DEBUGLOG(6, "large match (%u>%u), immediate encoding", maxML, sufficient_len); cur = 0; @@ -1018,24 +1114,25 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, } } /* set prices for first matches starting position == 0 */ - { U32 const literalsPrice = opt[0].price + ZSTD_litLengthPrice(0, optStatePtr, optLevel); + assert(opt[0].price >= 0); + { U32 const literalsPrice = (U32)opt[0].price + ZSTD_litLengthPrice(0, optStatePtr, optLevel); U32 pos; U32 matchNb; for (pos = 1; pos < minMatch; pos++) { opt[pos].price = ZSTD_MAX_PRICE; /* mlen, litlen and price will be fixed during forward scanning */ } for (matchNb = 0; matchNb < nbMatches; matchNb++) { - U32 const offset = matches[matchNb].off; + U32 const offcode = matches[matchNb].off; U32 const end = matches[matchNb].len; for ( ; pos <= end ; pos++ ) { - U32 const matchPrice = ZSTD_getMatchPrice(offset, pos, optStatePtr, optLevel); + U32 const matchPrice = ZSTD_getMatchPrice(offcode, pos, optStatePtr, optLevel); U32 const sequencePrice = literalsPrice + matchPrice; DEBUGLOG(7, "rPos:%u => set initial price : %.2f", pos, ZSTD_fCost(sequencePrice)); opt[pos].mlen = pos; - opt[pos].off = offset; + opt[pos].off = offcode; opt[pos].litlen = litlen; - opt[pos].price = sequencePrice; + opt[pos].price = (int)sequencePrice; } } last_pos = pos-1; } @@ -1050,9 +1147,9 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, /* Fix current position with one literal if cheaper */ { U32 const litlen = (opt[cur-1].mlen == 0) ? opt[cur-1].litlen + 1 : 1; int const price = opt[cur-1].price - + ZSTD_rawLiteralsCost(ip+cur-1, 1, optStatePtr, optLevel) - + ZSTD_litLengthPrice(litlen, optStatePtr, optLevel) - - ZSTD_litLengthPrice(litlen-1, optStatePtr, optLevel); + + (int)ZSTD_rawLiteralsCost(ip+cur-1, 1, optStatePtr, optLevel) + + (int)ZSTD_litLengthPrice(litlen, optStatePtr, optLevel) + - (int)ZSTD_litLengthPrice(litlen-1, optStatePtr, optLevel); assert(price < 1000000000); /* overflow check */ if (price <= opt[cur].price) { DEBUGLOG(7, "cPos:%zi==rPos:%u : better price (%.2f<=%.2f) using literal (ll==%u) (hist:%u,%u,%u)", @@ -1078,7 +1175,7 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, assert(cur >= opt[cur].mlen); if (opt[cur].mlen != 0) { U32 const prev = cur - opt[cur].mlen; - repcodes_t newReps = ZSTD_updateRep(opt[prev].rep, opt[cur].off, opt[cur].litlen==0); + repcodes_t const newReps = ZSTD_newRep(opt[prev].rep, opt[cur].off, opt[cur].litlen==0); ZSTD_memcpy(opt[cur].rep, &newReps, sizeof(repcodes_t)); } else { ZSTD_memcpy(opt[cur].rep, opt[cur - 1].rep, sizeof(repcodes_t)); @@ -1095,11 +1192,12 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, continue; /* skip unpromising positions; about ~+6% speed, -0.01 ratio */ } + assert(opt[cur].price >= 0); { U32 const ll0 = (opt[cur].mlen != 0); U32 const litlen = (opt[cur].mlen == 0) ? opt[cur].litlen : 0; - U32 const previousPrice = opt[cur].price; + U32 const previousPrice = (U32)opt[cur].price; U32 const basePrice = previousPrice + ZSTD_litLengthPrice(0, optStatePtr, optLevel); - U32 nbMatches = ZSTD_BtGetAllMatches(matches, ms, &nextToUpdate3, inr, iend, dictMode, opt[cur].rep, ll0, minMatch); + U32 nbMatches = getAllMatches(matches, ms, &nextToUpdate3, inr, iend, opt[cur].rep, ll0, minMatch); U32 matchNb; ZSTD_optLdm_processMatchCandidate(&optLdm, matches, &nbMatches, @@ -1137,7 +1235,7 @@ ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms, for (mlen = lastML; mlen >= startML; mlen--) { /* scan downward */ U32 const pos = cur + mlen; - int const price = basePrice + ZSTD_getMatchPrice(offset, mlen, optStatePtr, optLevel); + int const price = (int)basePrice + (int)ZSTD_getMatchPrice(offset, mlen, optStatePtr, optLevel); if ((pos > last_pos) || (price < opt[pos].price)) { DEBUGLOG(7, "rPos:%u (ml=%2u) => new better price (%.2f<%.2f)", @@ -1167,7 +1265,7 @@ _shortestPath: /* cur, last_pos, best_mlen, best_off have to be set */ * update them while traversing the sequences. */ if (lastSequence.mlen != 0) { - repcodes_t reps = ZSTD_updateRep(opt[cur].rep, lastSequence.off, lastSequence.litlen==0); + repcodes_t const reps = ZSTD_newRep(opt[cur].rep, lastSequence.off, lastSequence.litlen==0); ZSTD_memcpy(rep, &reps, sizeof(reps)); } else { ZSTD_memcpy(rep, opt[cur].rep, sizeof(repcodes_t)); @@ -1211,7 +1309,7 @@ _shortestPath: /* cur, last_pos, best_mlen, best_off have to be set */ assert(anchor + llen <= iend); ZSTD_updateStats(optStatePtr, llen, anchor, offCode, mlen); - ZSTD_storeSeq(seqStore, llen, anchor, iend, offCode, mlen-MINMATCH); + ZSTD_storeSeq(seqStore, llen, anchor, iend, offCode, mlen); anchor += advance; ip = anchor; } } @@ -1223,38 +1321,30 @@ _shortestPath: /* cur, last_pos, best_mlen, best_off have to be set */ return (size_t)(iend - anchor); } +static size_t ZSTD_compressBlock_opt0( + ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], + const void* src, size_t srcSize, const ZSTD_dictMode_e dictMode) +{ + return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 0 /* optLevel */, dictMode); +} + +static size_t ZSTD_compressBlock_opt2( + ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], + const void* src, size_t srcSize, const ZSTD_dictMode_e dictMode) +{ + return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /* optLevel */, dictMode); +} size_t ZSTD_compressBlock_btopt( ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], const void* src, size_t srcSize) { DEBUGLOG(5, "ZSTD_compressBlock_btopt"); - return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 0 /*optLevel*/, ZSTD_noDict); + return ZSTD_compressBlock_opt0(ms, seqStore, rep, src, srcSize, ZSTD_noDict); } -/* used in 2-pass strategy */ -static U32 ZSTD_upscaleStat(unsigned* table, U32 lastEltIndex, int bonus) -{ - U32 s, sum=0; - assert(ZSTD_FREQ_DIV+bonus >= 0); - for (s=0; s<lastEltIndex+1; s++) { - table[s] <<= ZSTD_FREQ_DIV+bonus; - table[s]--; - sum += table[s]; - } - return sum; -} -/* used in 2-pass strategy */ -MEM_STATIC void ZSTD_upscaleStats(optState_t* optPtr) -{ - if (ZSTD_compressedLiterals(optPtr)) - optPtr->litSum = ZSTD_upscaleStat(optPtr->litFreq, MaxLit, 0); - optPtr->litLengthSum = ZSTD_upscaleStat(optPtr->litLengthFreq, MaxLL, 0); - optPtr->matchLengthSum = ZSTD_upscaleStat(optPtr->matchLengthFreq, MaxML, 0); - optPtr->offCodeSum = ZSTD_upscaleStat(optPtr->offCodeFreq, MaxOff, 0); -} /* ZSTD_initStats_ultra(): * make a first compression pass, just to seed stats with more accurate starting values. @@ -1276,7 +1366,7 @@ ZSTD_initStats_ultra(ZSTD_matchState_t* ms, assert(ms->window.dictLimit == ms->window.lowLimit); /* no dictionary */ assert(ms->window.dictLimit - ms->nextToUpdate <= 1); /* no prefix (note: intentional overflow, defined as 2-complement) */ - ZSTD_compressBlock_opt_generic(ms, seqStore, tmpRep, src, srcSize, 2 /*optLevel*/, ZSTD_noDict); /* generate stats into ms->opt*/ + ZSTD_compressBlock_opt2(ms, seqStore, tmpRep, src, srcSize, ZSTD_noDict); /* generate stats into ms->opt*/ /* invalidate first scan from history */ ZSTD_resetSeqStore(seqStore); @@ -1285,8 +1375,6 @@ ZSTD_initStats_ultra(ZSTD_matchState_t* ms, ms->window.lowLimit = ms->window.dictLimit; ms->nextToUpdate = ms->window.dictLimit; - /* re-inforce weight of collected statistics */ - ZSTD_upscaleStats(&ms->opt); } size_t ZSTD_compressBlock_btultra( @@ -1294,7 +1382,7 @@ size_t ZSTD_compressBlock_btultra( const void* src, size_t srcSize) { DEBUGLOG(5, "ZSTD_compressBlock_btultra (srcSize=%zu)", srcSize); - return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /*optLevel*/, ZSTD_noDict); + return ZSTD_compressBlock_opt2(ms, seqStore, rep, src, srcSize, ZSTD_noDict); } size_t ZSTD_compressBlock_btultra2( @@ -1322,35 +1410,35 @@ size_t ZSTD_compressBlock_btultra2( ZSTD_initStats_ultra(ms, seqStore, rep, src, srcSize); } - return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /*optLevel*/, ZSTD_noDict); + return ZSTD_compressBlock_opt2(ms, seqStore, rep, src, srcSize, ZSTD_noDict); } size_t ZSTD_compressBlock_btopt_dictMatchState( ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], const void* src, size_t srcSize) { - return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 0 /*optLevel*/, ZSTD_dictMatchState); + return ZSTD_compressBlock_opt0(ms, seqStore, rep, src, srcSize, ZSTD_dictMatchState); } size_t ZSTD_compressBlock_btultra_dictMatchState( ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], const void* src, size_t srcSize) { - return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /*optLevel*/, ZSTD_dictMatchState); + return ZSTD_compressBlock_opt2(ms, seqStore, rep, src, srcSize, ZSTD_dictMatchState); } size_t ZSTD_compressBlock_btopt_extDict( ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], const void* src, size_t srcSize) { - return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 0 /*optLevel*/, ZSTD_extDict); + return ZSTD_compressBlock_opt0(ms, seqStore, rep, src, srcSize, ZSTD_extDict); } size_t ZSTD_compressBlock_btultra_extDict( ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], const void* src, size_t srcSize) { - return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /*optLevel*/, ZSTD_extDict); + return ZSTD_compressBlock_opt2(ms, seqStore, rep, src, srcSize, ZSTD_extDict); } /* note : no btultra2 variant for extDict nor dictMatchState, |