contrib/zstd/lib/compress/zstd_lazy.c in extzstd-0.3.1 vs contrib/zstd/lib/compress/zstd_lazy.c in extzstd-0.3.2

- old
+ new

@@ -56,15 +56,15 @@ } /** ZSTD_insertDUBT1() : * sort one already inserted but unsorted position - * assumption : current >= btlow == (current - btmask) + * assumption : curr >= btlow == (curr - btmask) * doesn't fail */ static void ZSTD_insertDUBT1(ZSTD_matchState_t* ms, - U32 current, const BYTE* inputEnd, + U32 curr, const BYTE* inputEnd, U32 nbCompares, U32 btLow, const ZSTD_dictMode_e dictMode) { const ZSTD_compressionParameters* const cParams = &ms->cParams; U32* const bt = ms->chainTable; @@ -72,56 +72,56 @@ U32 const btMask = (1 << btLog) - 1; size_t commonLengthSmaller=0, commonLengthLarger=0; const BYTE* const base = ms->window.base; const BYTE* const dictBase = ms->window.dictBase; const U32 dictLimit = ms->window.dictLimit; - const BYTE* const ip = (current>=dictLimit) ? base + current : dictBase + current; - const BYTE* const iend = (current>=dictLimit) ? inputEnd : dictBase + dictLimit; + const BYTE* const ip = (curr>=dictLimit) ? base + curr : dictBase + curr; + const BYTE* const iend = (curr>=dictLimit) ? inputEnd : dictBase + dictLimit; const BYTE* const dictEnd = dictBase + dictLimit; const BYTE* const prefixStart = base + dictLimit; const BYTE* match; - U32* smallerPtr = bt + 2*(current&btMask); + U32* smallerPtr = bt + 2*(curr&btMask); U32* largerPtr = smallerPtr + 1; U32 matchIndex = *smallerPtr; /* this candidate is unsorted : next sorted candidate is reached through *smallerPtr, while *largerPtr contains previous unsorted candidate (which is already saved and can be overwritten) */ U32 dummy32; /* to be nullified at the end */ U32 const windowValid = ms->window.lowLimit; U32 const maxDistance = 1U << cParams->windowLog; - U32 const windowLow = (current - windowValid > maxDistance) ? current - maxDistance : windowValid; + U32 const windowLow = (curr - windowValid > maxDistance) ? curr - maxDistance : windowValid; DEBUGLOG(8, "ZSTD_insertDUBT1(%u) (dictLimit=%u, lowLimit=%u)", - current, dictLimit, windowLow); - assert(current >= btLow); + curr, dictLimit, windowLow); + assert(curr >= btLow); assert(ip < iend); /* condition for ZSTD_count */ while (nbCompares-- && (matchIndex > windowLow)) { U32* const nextPtr = bt + 2*(matchIndex & btMask); size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ - assert(matchIndex < current); + assert(matchIndex < curr); /* note : all candidates are now supposed sorted, * but it's still possible to have nextPtr[1] == ZSTD_DUBT_UNSORTED_MARK * when a real index has the same value as ZSTD_DUBT_UNSORTED_MARK */ if ( (dictMode != ZSTD_extDict) || (matchIndex+matchLength >= dictLimit) /* both in current segment*/ - || (current < dictLimit) /* both in extDict */) { + || (curr < dictLimit) /* both in extDict */) { const BYTE* const mBase = ( (dictMode != ZSTD_extDict) || (matchIndex+matchLength >= dictLimit)) ? base : dictBase; assert( (matchIndex+matchLength >= dictLimit) /* might be wrong if extDict is incorrectly set to 0 */ - || (current < dictLimit) ); + || (curr < dictLimit) ); match = mBase + matchIndex; matchLength += ZSTD_count(ip+matchLength, match+matchLength, iend); } else { match = dictBase + matchIndex; matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iend, dictEnd, prefixStart); if (matchIndex+matchLength >= dictLimit) match = base + matchIndex; /* preparation for next read of match[matchLength] */ } DEBUGLOG(8, "ZSTD_insertDUBT1: comparing %u with %u : found %u common bytes ", - current, matchIndex, (U32)matchLength); + curr, matchIndex, (U32)matchLength); if (ip+matchLength == iend) { /* equal : no way to know if inf or sup */ break; /* drop , to guarantee consistency ; miss a bit of compression, but other solutions can corrupt tree */ } @@ -166,11 +166,11 @@ size_t const h = ZSTD_hashPtr(ip, hashLog, mls); U32 dictMatchIndex = dictHashTable[h]; const BYTE* const base = ms->window.base; const BYTE* const prefixStart = base + ms->window.dictLimit; - U32 const current = (U32)(ip-base); + U32 const curr = (U32)(ip-base); const BYTE* const dictBase = dms->window.base; const BYTE* const dictEnd = dms->window.nextSrc; U32 const dictHighLimit = (U32)(dms->window.nextSrc - dms->window.base); U32 const dictLowLimit = dms->window.lowLimit; U32 const dictIndexDelta = ms->window.lowLimit - dictHighLimit; @@ -193,14 +193,14 @@ if (dictMatchIndex+matchLength >= dictHighLimit) match = base + dictMatchIndex + dictIndexDelta; /* to prepare for next usage of match[matchLength] */ if (matchLength > bestLength) { U32 matchIndex = dictMatchIndex + dictIndexDelta; - if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(current-matchIndex+1) - ZSTD_highbit32((U32)offsetPtr[0]+1)) ) { + if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(curr-matchIndex+1) - ZSTD_highbit32((U32)offsetPtr[0]+1)) ) { DEBUGLOG(9, "ZSTD_DUBT_findBetterDictMatch(%u) : found better match length %u -> %u and offsetCode %u -> %u (dictMatchIndex %u, matchIndex %u)", - current, (U32)bestLength, (U32)matchLength, (U32)*offsetPtr, ZSTD_REP_MOVE + current - matchIndex, dictMatchIndex, matchIndex); - bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + current - matchIndex; + curr, (U32)bestLength, (U32)matchLength, (U32)*offsetPtr, ZSTD_REP_MOVE + curr - matchIndex, dictMatchIndex, matchIndex); + bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + curr - matchIndex; } if (ip+matchLength == iend) { /* reached end of input : ip[matchLength] is not valid, no way to know if it's larger or smaller than match */ break; /* drop, to guarantee consistency (miss a little bit of compression) */ } } @@ -216,13 +216,13 @@ dictMatchIndex = nextPtr[0]; } } if (bestLength >= MINMATCH) { - U32 const mIndex = current - ((U32)*offsetPtr - ZSTD_REP_MOVE); (void)mIndex; + U32 const mIndex = curr - ((U32)*offsetPtr - ZSTD_REP_MOVE); (void)mIndex; DEBUGLOG(8, "ZSTD_DUBT_findBetterDictMatch(%u) : found match of length %u and offsetCode %u (pos %u)", - current, (U32)bestLength, (U32)*offsetPtr, mIndex); + curr, (U32)bestLength, (U32)*offsetPtr, mIndex); } return bestLength; } @@ -239,27 +239,28 @@ U32 const hashLog = cParams->hashLog; size_t const h = ZSTD_hashPtr(ip, hashLog, mls); U32 matchIndex = hashTable[h]; const BYTE* const base = ms->window.base; - U32 const current = (U32)(ip-base); - U32 const windowLow = ZSTD_getLowestMatchIndex(ms, current, cParams->windowLog); + U32 const curr = (U32)(ip-base); + U32 const windowLow = ZSTD_getLowestMatchIndex(ms, curr, cParams->windowLog); U32* const bt = ms->chainTable; U32 const btLog = cParams->chainLog - 1; U32 const btMask = (1 << btLog) - 1; - U32 const btLow = (btMask >= current) ? 0 : current - btMask; + U32 const btLow = (btMask >= curr) ? 0 : curr - btMask; U32 const unsortLimit = MAX(btLow, windowLow); U32* nextCandidate = bt + 2*(matchIndex&btMask); U32* unsortedMark = bt + 2*(matchIndex&btMask) + 1; U32 nbCompares = 1U << cParams->searchLog; U32 nbCandidates = nbCompares; U32 previousCandidate = 0; - DEBUGLOG(7, "ZSTD_DUBT_findBestMatch (%u) ", current); + DEBUGLOG(7, "ZSTD_DUBT_findBestMatch (%u) ", curr); assert(ip <= iend-8); /* required for h calculation */ + assert(dictMode != ZSTD_dedicatedDictSearch); /* reach end of unsorted candidates list */ while ( (matchIndex > unsortLimit) && (*unsortedMark == ZSTD_DUBT_UNSORTED_MARK) && (nbCandidates > 1) ) { @@ -297,18 +298,18 @@ { size_t commonLengthSmaller = 0, commonLengthLarger = 0; const BYTE* const dictBase = ms->window.dictBase; const U32 dictLimit = ms->window.dictLimit; const BYTE* const dictEnd = dictBase + dictLimit; const BYTE* const prefixStart = base + dictLimit; - U32* smallerPtr = bt + 2*(current&btMask); - U32* largerPtr = bt + 2*(current&btMask) + 1; - U32 matchEndIdx = current + 8 + 1; + U32* smallerPtr = bt + 2*(curr&btMask); + U32* largerPtr = bt + 2*(curr&btMask) + 1; + U32 matchEndIdx = curr + 8 + 1; U32 dummy32; /* to be nullified at the end */ size_t bestLength = 0; matchIndex = hashTable[h]; - hashTable[h] = current; /* Update Hash Table */ + hashTable[h] = curr; /* Update Hash Table */ while (nbCompares-- && (matchIndex > windowLow)) { U32* const nextPtr = bt + 2*(matchIndex & btMask); size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ const BYTE* match; @@ -324,12 +325,12 @@ } if (matchLength > bestLength) { if (matchLength > matchEndIdx - matchIndex) matchEndIdx = matchIndex + (U32)matchLength; - if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(current-matchIndex+1) - ZSTD_highbit32((U32)offsetPtr[0]+1)) ) - bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + current - matchIndex; + if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(curr-matchIndex+1) - ZSTD_highbit32((U32)offsetPtr[0]+1)) ) + bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + curr - matchIndex; if (ip+matchLength == iend) { /* equal : no way to know if inf or sup */ if (dictMode == ZSTD_dictMatchState) { nbCompares = 0; /* in addition to avoiding checking any * further in this loop, make sure we * skip checking in the dictionary. */ @@ -361,16 +362,16 @@ ms, ip, iend, offsetPtr, bestLength, nbCompares, mls, dictMode); } - assert(matchEndIdx > current+8); /* ensure nextToUpdate is increased */ + assert(matchEndIdx > curr+8); /* ensure nextToUpdate is increased */ ms->nextToUpdate = matchEndIdx - 8; /* skip repetitive patterns */ if (bestLength >= MINMATCH) { - U32 const mIndex = current - ((U32)*offsetPtr - ZSTD_REP_MOVE); (void)mIndex; + U32 const mIndex = curr - ((U32)*offsetPtr - ZSTD_REP_MOVE); (void)mIndex; DEBUGLOG(8, "ZSTD_DUBT_findBestMatch(%u) : found match of length %u and offsetCode %u (pos %u)", - current, (U32)bestLength, (U32)*offsetPtr, mIndex); + curr, (U32)bestLength, (U32)*offsetPtr, mIndex); } return bestLength; } } @@ -444,11 +445,11 @@ ***********************************/ #define NEXT_IN_CHAIN(d, mask) chainTable[(d) & (mask)] /* Update chains up to ip (excluded) Assumption : always within prefix (i.e. not within extDict) */ -static U32 ZSTD_insertAndFindFirstIndex_internal( +FORCE_INLINE_TEMPLATE U32 ZSTD_insertAndFindFirstIndex_internal( ZSTD_matchState_t* ms, const ZSTD_compressionParameters* const cParams, const BYTE* ip, U32 const mls) { U32* const hashTable = ms->hashTable; @@ -473,11 +474,126 @@ U32 ZSTD_insertAndFindFirstIndex(ZSTD_matchState_t* ms, const BYTE* ip) { const ZSTD_compressionParameters* const cParams = &ms->cParams; return ZSTD_insertAndFindFirstIndex_internal(ms, cParams, ip, ms->cParams.minMatch); } +void ZSTD_dedicatedDictSearch_lazy_loadDictionary(ZSTD_matchState_t* ms, const BYTE* const ip) +{ + const BYTE* const base = ms->window.base; + U32 const target = (U32)(ip - base); + U32* const hashTable = ms->hashTable; + U32* const chainTable = ms->chainTable; + U32 const chainSize = 1 << ms->cParams.chainLog; + U32 idx = ms->nextToUpdate; + U32 const minChain = chainSize < target ? target - chainSize : idx; + U32 const bucketSize = 1 << ZSTD_LAZY_DDSS_BUCKET_LOG; + U32 const cacheSize = bucketSize - 1; + U32 const chainAttempts = (1 << ms->cParams.searchLog) - cacheSize; + U32 const chainLimit = chainAttempts > 255 ? 255 : chainAttempts; + /* We know the hashtable is oversized by a factor of `bucketSize`. + * We are going to temporarily pretend `bucketSize == 1`, keeping only a + * single entry. We will use the rest of the space to construct a temporary + * chaintable. + */ + U32 const hashLog = ms->cParams.hashLog - ZSTD_LAZY_DDSS_BUCKET_LOG; + U32* const tmpHashTable = hashTable; + U32* const tmpChainTable = hashTable + ((size_t)1 << hashLog); + U32 const tmpChainSize = ((1 << ZSTD_LAZY_DDSS_BUCKET_LOG) - 1) << hashLog; + U32 const tmpMinChain = tmpChainSize < target ? target - tmpChainSize : idx; + + U32 hashIdx; + + assert(ms->cParams.chainLog <= 24); + assert(ms->cParams.hashLog >= ms->cParams.chainLog); + assert(idx != 0); + assert(tmpMinChain <= minChain); + + /* fill conventional hash table and conventional chain table */ + for ( ; idx < target; idx++) { + U32 const h = (U32)ZSTD_hashPtr(base + idx, hashLog, ms->cParams.minMatch); + if (idx >= tmpMinChain) { + tmpChainTable[idx - tmpMinChain] = hashTable[h]; + } + tmpHashTable[h] = idx; + } + + /* sort chains into ddss chain table */ + { + U32 chainPos = 0; + for (hashIdx = 0; hashIdx < (1U << hashLog); hashIdx++) { + U32 count; + U32 countBeyondMinChain = 0; + U32 i = tmpHashTable[hashIdx]; + for (count = 0; i >= tmpMinChain && count < cacheSize; count++) { + /* skip through the chain to the first position that won't be + * in the hash cache bucket */ + if (i < minChain) { + countBeyondMinChain++; + } + i = tmpChainTable[i - tmpMinChain]; + } + if (count == cacheSize) { + for (count = 0; count < chainLimit;) { + if (i < minChain) { + if (!i || countBeyondMinChain++ > cacheSize) { + /* only allow pulling `cacheSize` number of entries + * into the cache or chainTable beyond `minChain`, + * to replace the entries pulled out of the + * chainTable into the cache. This lets us reach + * back further without increasing the total number + * of entries in the chainTable, guaranteeing the + * DDSS chain table will fit into the space + * allocated for the regular one. */ + break; + } + } + chainTable[chainPos++] = i; + count++; + if (i < tmpMinChain) { + break; + } + i = tmpChainTable[i - tmpMinChain]; + } + } else { + count = 0; + } + if (count) { + tmpHashTable[hashIdx] = ((chainPos - count) << 8) + count; + } else { + tmpHashTable[hashIdx] = 0; + } + } + assert(chainPos <= chainSize); /* I believe this is guaranteed... */ + } + + /* move chain pointers into the last entry of each hash bucket */ + for (hashIdx = (1 << hashLog); hashIdx; ) { + U32 const bucketIdx = --hashIdx << ZSTD_LAZY_DDSS_BUCKET_LOG; + U32 const chainPackedPointer = tmpHashTable[hashIdx]; + U32 i; + for (i = 0; i < cacheSize; i++) { + hashTable[bucketIdx + i] = 0; + } + hashTable[bucketIdx + bucketSize - 1] = chainPackedPointer; + } + + /* fill the buckets of the hash table */ + for (idx = ms->nextToUpdate; idx < target; idx++) { + U32 const h = (U32)ZSTD_hashPtr(base + idx, hashLog, ms->cParams.minMatch) + << ZSTD_LAZY_DDSS_BUCKET_LOG; + U32 i; + /* Shift hash cache down 1. */ + for (i = cacheSize - 1; i; i--) + hashTable[h + i] = hashTable[h + i - 1]; + hashTable[h] = idx; + } + + ms->nextToUpdate = target; +} + + /* inlining is important to hardwire a hot branch (template emulation) */ FORCE_INLINE_TEMPLATE size_t ZSTD_HcFindBestMatch_generic ( ZSTD_matchState_t* ms, const BYTE* const ip, const BYTE* const iLimit, @@ -491,24 +607,37 @@ const BYTE* const base = ms->window.base; const BYTE* const dictBase = ms->window.dictBase; const U32 dictLimit = ms->window.dictLimit; const BYTE* const prefixStart = base + dictLimit; const BYTE* const dictEnd = dictBase + dictLimit; - const U32 current = (U32)(ip-base); + const U32 curr = (U32)(ip-base); const U32 maxDistance = 1U << cParams->windowLog; const U32 lowestValid = ms->window.lowLimit; - const U32 withinMaxDistance = (current - lowestValid > maxDistance) ? current - maxDistance : lowestValid; + const U32 withinMaxDistance = (curr - lowestValid > maxDistance) ? curr - maxDistance : lowestValid; const U32 isDictionary = (ms->loadedDictEnd != 0); const U32 lowLimit = isDictionary ? lowestValid : withinMaxDistance; - const U32 minChain = current > chainSize ? current - chainSize : 0; + const U32 minChain = curr > chainSize ? curr - chainSize : 0; U32 nbAttempts = 1U << cParams->searchLog; size_t ml=4-1; + const ZSTD_matchState_t* const dms = ms->dictMatchState; + const U32 ddsHashLog = dictMode == ZSTD_dedicatedDictSearch + ? dms->cParams.hashLog - ZSTD_LAZY_DDSS_BUCKET_LOG : 0; + const size_t ddsIdx = dictMode == ZSTD_dedicatedDictSearch + ? ZSTD_hashPtr(ip, ddsHashLog, mls) << ZSTD_LAZY_DDSS_BUCKET_LOG : 0; + + U32 matchIndex; + + if (dictMode == ZSTD_dedicatedDictSearch) { + const U32* entry = &dms->hashTable[ddsIdx]; + PREFETCH_L1(entry); + } + /* HC4 match finder */ - U32 matchIndex = ZSTD_insertAndFindFirstIndex_internal(ms, cParams, ip, mls); + matchIndex = ZSTD_insertAndFindFirstIndex_internal(ms, cParams, ip, mls); - for ( ; (matchIndex>lowLimit) & (nbAttempts>0) ; nbAttempts--) { + for ( ; (matchIndex>=lowLimit) & (nbAttempts>0) ; nbAttempts--) { size_t currentMl=0; if ((dictMode != ZSTD_extDict) || matchIndex >= dictLimit) { const BYTE* const match = base + matchIndex; assert(matchIndex >= dictLimit); /* ensures this is true if dictMode != ZSTD_extDict */ if (match[ml] == ip[ml]) /* potentially better */ @@ -521,20 +650,104 @@ } /* save best solution */ if (currentMl > ml) { ml = currentMl; - *offsetPtr = current - matchIndex + ZSTD_REP_MOVE; + *offsetPtr = curr - matchIndex + ZSTD_REP_MOVE; if (ip+currentMl == iLimit) break; /* best possible, avoids read overflow on next attempt */ } if (matchIndex <= minChain) break; matchIndex = NEXT_IN_CHAIN(matchIndex, chainMask); } - if (dictMode == ZSTD_dictMatchState) { - const ZSTD_matchState_t* const dms = ms->dictMatchState; + if (dictMode == ZSTD_dedicatedDictSearch) { + const U32 ddsLowestIndex = dms->window.dictLimit; + const BYTE* const ddsBase = dms->window.base; + const BYTE* const ddsEnd = dms->window.nextSrc; + const U32 ddsSize = (U32)(ddsEnd - ddsBase); + const U32 ddsIndexDelta = dictLimit - ddsSize; + const U32 bucketSize = (1 << ZSTD_LAZY_DDSS_BUCKET_LOG); + const U32 bucketLimit = nbAttempts < bucketSize - 1 ? nbAttempts : bucketSize - 1; + U32 ddsAttempt; + + for (ddsAttempt = 0; ddsAttempt < bucketSize - 1; ddsAttempt++) { + PREFETCH_L1(ddsBase + dms->hashTable[ddsIdx + ddsAttempt]); + } + + { + U32 const chainPackedPointer = dms->hashTable[ddsIdx + bucketSize - 1]; + U32 const chainIndex = chainPackedPointer >> 8; + + PREFETCH_L1(&dms->chainTable[chainIndex]); + } + + for (ddsAttempt = 0; ddsAttempt < bucketLimit; ddsAttempt++) { + size_t currentMl=0; + const BYTE* match; + matchIndex = dms->hashTable[ddsIdx + ddsAttempt]; + match = ddsBase + matchIndex; + + if (!matchIndex) { + return ml; + } + + /* guaranteed by table construction */ + (void)ddsLowestIndex; + assert(matchIndex >= ddsLowestIndex); + assert(match+4 <= ddsEnd); + if (MEM_read32(match) == MEM_read32(ip)) { + /* assumption : matchIndex <= dictLimit-4 (by table construction) */ + currentMl = ZSTD_count_2segments(ip+4, match+4, iLimit, ddsEnd, prefixStart) + 4; + } + + /* save best solution */ + if (currentMl > ml) { + ml = currentMl; + *offsetPtr = curr - (matchIndex + ddsIndexDelta) + ZSTD_REP_MOVE; + if (ip+currentMl == iLimit) { + /* best possible, avoids read overflow on next attempt */ + return ml; + } + } + } + + { + U32 const chainPackedPointer = dms->hashTable[ddsIdx + bucketSize - 1]; + U32 chainIndex = chainPackedPointer >> 8; + U32 const chainLength = chainPackedPointer & 0xFF; + U32 const chainAttempts = nbAttempts - ddsAttempt; + U32 const chainLimit = chainAttempts > chainLength ? chainLength : chainAttempts; + U32 chainAttempt; + + for (chainAttempt = 0 ; chainAttempt < chainLimit; chainAttempt++) { + PREFETCH_L1(ddsBase + dms->chainTable[chainIndex + chainAttempt]); + } + + for (chainAttempt = 0 ; chainAttempt < chainLimit; chainAttempt++, chainIndex++) { + size_t currentMl=0; + const BYTE* match; + matchIndex = dms->chainTable[chainIndex]; + match = ddsBase + matchIndex; + + /* guaranteed by table construction */ + assert(matchIndex >= ddsLowestIndex); + assert(match+4 <= ddsEnd); + if (MEM_read32(match) == MEM_read32(ip)) { + /* assumption : matchIndex <= dictLimit-4 (by table construction) */ + currentMl = ZSTD_count_2segments(ip+4, match+4, iLimit, ddsEnd, prefixStart) + 4; + } + + /* save best solution */ + if (currentMl > ml) { + ml = currentMl; + *offsetPtr = curr - (matchIndex + ddsIndexDelta) + ZSTD_REP_MOVE; + if (ip+currentMl == iLimit) break; /* best possible, avoids read overflow on next attempt */ + } + } + } + } else if (dictMode == ZSTD_dictMatchState) { const U32* const dmsChainTable = dms->chainTable; const U32 dmsChainSize = (1 << dms->cParams.chainLog); const U32 dmsChainMask = dmsChainSize - 1; const U32 dmsLowestIndex = dms->window.dictLimit; const BYTE* const dmsBase = dms->window.base; @@ -543,25 +756,26 @@ const U32 dmsIndexDelta = dictLimit - dmsSize; const U32 dmsMinChain = dmsSize > dmsChainSize ? dmsSize - dmsChainSize : 0; matchIndex = dms->hashTable[ZSTD_hashPtr(ip, dms->cParams.hashLog, mls)]; - for ( ; (matchIndex>dmsLowestIndex) & (nbAttempts>0) ; nbAttempts--) { + for ( ; (matchIndex>=dmsLowestIndex) & (nbAttempts>0) ; nbAttempts--) { size_t currentMl=0; const BYTE* const match = dmsBase + matchIndex; assert(match+4 <= dmsEnd); if (MEM_read32(match) == MEM_read32(ip)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */ currentMl = ZSTD_count_2segments(ip+4, match+4, iLimit, dmsEnd, prefixStart) + 4; /* save best solution */ if (currentMl > ml) { ml = currentMl; - *offsetPtr = current - (matchIndex + dmsIndexDelta) + ZSTD_REP_MOVE; + *offsetPtr = curr - (matchIndex + dmsIndexDelta) + ZSTD_REP_MOVE; if (ip+currentMl == iLimit) break; /* best possible, avoids read overflow on next attempt */ } if (matchIndex <= dmsMinChain) break; + matchIndex = dmsChainTable[matchIndex & dmsChainMask]; } } return ml; @@ -598,10 +812,26 @@ case 6 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 6, ZSTD_dictMatchState); } } +static size_t ZSTD_HcFindBestMatch_dedicatedDictSearch_selectMLS ( + ZSTD_matchState_t* ms, + const BYTE* ip, const BYTE* const iLimit, + size_t* offsetPtr) +{ + switch(ms->cParams.minMatch) + { + default : /* includes case 3 */ + case 4 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 4, ZSTD_dedicatedDictSearch); + case 5 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 5, ZSTD_dedicatedDictSearch); + case 7 : + case 6 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 6, ZSTD_dedicatedDictSearch); + } +} + + FORCE_INLINE_TEMPLATE size_t ZSTD_HcFindBestMatch_extDict_selectMLS ( ZSTD_matchState_t* ms, const BYTE* ip, const BYTE* const iLimit, size_t* offsetPtr) { @@ -639,43 +869,66 @@ const BYTE* const prefixLowest = base + prefixLowestIndex; typedef size_t (*searchMax_f)( ZSTD_matchState_t* ms, const BYTE* ip, const BYTE* iLimit, size_t* offsetPtr); - searchMax_f const searchMax = dictMode == ZSTD_dictMatchState ? - (searchMethod==search_binaryTree ? ZSTD_BtFindBestMatch_dictMatchState_selectMLS - : ZSTD_HcFindBestMatch_dictMatchState_selectMLS) : - (searchMethod==search_binaryTree ? ZSTD_BtFindBestMatch_selectMLS - : ZSTD_HcFindBestMatch_selectMLS); + + /** + * This table is indexed first by the four ZSTD_dictMode_e values, and then + * by the two searchMethod_e values. NULLs are placed for configurations + * that should never occur (extDict modes go to the other implementation + * below and there is no DDSS for binary tree search yet). + */ + const searchMax_f searchFuncs[4][2] = { + { + ZSTD_HcFindBestMatch_selectMLS, + ZSTD_BtFindBestMatch_selectMLS + }, + { + NULL, + NULL + }, + { + ZSTD_HcFindBestMatch_dictMatchState_selectMLS, + ZSTD_BtFindBestMatch_dictMatchState_selectMLS + }, + { + ZSTD_HcFindBestMatch_dedicatedDictSearch_selectMLS, + NULL + } + }; + + searchMax_f const searchMax = searchFuncs[dictMode][searchMethod == search_binaryTree]; U32 offset_1 = rep[0], offset_2 = rep[1], savedOffset=0; + const int isDMS = dictMode == ZSTD_dictMatchState; + const int isDDS = dictMode == ZSTD_dedicatedDictSearch; + const int isDxS = isDMS || isDDS; const ZSTD_matchState_t* const dms = ms->dictMatchState; - const U32 dictLowestIndex = dictMode == ZSTD_dictMatchState ? - dms->window.dictLimit : 0; - const BYTE* const dictBase = dictMode == ZSTD_dictMatchState ? - dms->window.base : NULL; - const BYTE* const dictLowest = dictMode == ZSTD_dictMatchState ? - dictBase + dictLowestIndex : NULL; - const BYTE* const dictEnd = dictMode == ZSTD_dictMatchState ? - dms->window.nextSrc : NULL; - const U32 dictIndexDelta = dictMode == ZSTD_dictMatchState ? + const U32 dictLowestIndex = isDxS ? dms->window.dictLimit : 0; + const BYTE* const dictBase = isDxS ? dms->window.base : NULL; + const BYTE* const dictLowest = isDxS ? dictBase + dictLowestIndex : NULL; + const BYTE* const dictEnd = isDxS ? dms->window.nextSrc : NULL; + const U32 dictIndexDelta = isDxS ? prefixLowestIndex - (U32)(dictEnd - dictBase) : 0; const U32 dictAndPrefixLength = (U32)((ip - prefixLowest) + (dictEnd - dictLowest)); + assert(searchMax != NULL); + DEBUGLOG(5, "ZSTD_compressBlock_lazy_generic (dictMode=%u)", (U32)dictMode); /* init */ ip += (dictAndPrefixLength == 0); if (dictMode == ZSTD_noDict) { - U32 const current = (U32)(ip - base); - U32 const windowLow = ZSTD_getLowestPrefixIndex(ms, current, ms->cParams.windowLog); - U32 const maxRep = current - windowLow; + U32 const curr = (U32)(ip - base); + U32 const windowLow = ZSTD_getLowestPrefixIndex(ms, curr, ms->cParams.windowLog); + U32 const maxRep = curr - windowLow; if (offset_2 > maxRep) savedOffset = offset_2, offset_2 = 0; if (offset_1 > maxRep) savedOffset = offset_1, offset_1 = 0; } - if (dictMode == ZSTD_dictMatchState) { + if (isDxS) { /* dictMatchState repCode checks don't currently handle repCode == 0 * disabling. */ assert(offset_1 <= dictAndPrefixLength); assert(offset_2 <= dictAndPrefixLength); } @@ -691,13 +944,13 @@ size_t matchLength=0; size_t offset=0; const BYTE* start=ip+1; /* check repCode */ - if (dictMode == ZSTD_dictMatchState) { + if (isDxS) { const U32 repIndex = (U32)(ip - base) + 1 - offset_1; - const BYTE* repMatch = (dictMode == ZSTD_dictMatchState + const BYTE* repMatch = ((dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch) && repIndex < prefixLowestIndex) ? dictBase + (repIndex - dictIndexDelta) : base + repIndex; if (((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) { @@ -734,11 +987,11 @@ int const gain2 = (int)(mlRep * 3); int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1); if ((mlRep >= 4) && (gain2 > gain1)) matchLength = mlRep, offset = 0, start = ip; } - if (dictMode == ZSTD_dictMatchState) { + if (isDxS) { const U32 repIndex = (U32)(ip - base) - offset_1; const BYTE* repMatch = repIndex < prefixLowestIndex ? dictBase + (repIndex - dictIndexDelta) : base + repIndex; if (((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) @@ -769,11 +1022,11 @@ int const gain2 = (int)(mlRep * 4); int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1); if ((mlRep >= 4) && (gain2 > gain1)) matchLength = mlRep, offset = 0, start = ip; } - if (dictMode == ZSTD_dictMatchState) { + if (isDxS) { const U32 repIndex = (U32)(ip - base) - offset_1; const BYTE* repMatch = repIndex < prefixLowestIndex ? dictBase + (repIndex - dictIndexDelta) : base + repIndex; if (((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) @@ -807,11 +1060,11 @@ if (dictMode == ZSTD_noDict) { while ( ((start > anchor) & (start - (offset-ZSTD_REP_MOVE) > prefixLowest)) && (start[-1] == (start-(offset-ZSTD_REP_MOVE))[-1]) ) /* only search for offset within prefix */ { start--; matchLength++; } } - if (dictMode == ZSTD_dictMatchState) { + if (isDxS) { U32 const matchIndex = (U32)((start-base) - (offset - ZSTD_REP_MOVE)); const BYTE* match = (matchIndex < prefixLowestIndex) ? dictBase + matchIndex - dictIndexDelta : base + matchIndex; const BYTE* const mStart = (matchIndex < prefixLowestIndex) ? dictLowest : prefixLowest; while ((start>anchor) && (match>mStart) && (start[-1] == match[-1])) { start--; match--; matchLength++; } /* catch up */ } @@ -823,16 +1076,15 @@ ZSTD_storeSeq(seqStore, litLength, anchor, iend, (U32)offset, matchLength-MINMATCH); anchor = ip = start + matchLength; } /* check immediate repcode */ - if (dictMode == ZSTD_dictMatchState) { + if (isDxS) { while (ip <= ilimit) { U32 const current2 = (U32)(ip-base); U32 const repIndex = current2 - offset_2; - const BYTE* repMatch = dictMode == ZSTD_dictMatchState - && repIndex < prefixLowestIndex ? + const BYTE* repMatch = repIndex < prefixLowestIndex ? dictBase - dictIndexDelta + repIndex : base + repIndex; if ( ((U32)((prefixLowestIndex-1) - (U32)repIndex) >= 3 /* intentional overflow */) && (MEM_read32(repMatch) == MEM_read32(ip)) ) { const BYTE* const repEnd2 = repIndex < prefixLowestIndex ? dictEnd : iend; @@ -923,10 +1175,32 @@ { return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, search_hashChain, 0, ZSTD_dictMatchState); } +size_t ZSTD_compressBlock_lazy2_dedicatedDictSearch( + ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], + void const* src, size_t srcSize) +{ + return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, search_hashChain, 2, ZSTD_dedicatedDictSearch); +} + +size_t ZSTD_compressBlock_lazy_dedicatedDictSearch( + ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], + void const* src, size_t srcSize) +{ + return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, search_hashChain, 1, ZSTD_dedicatedDictSearch); +} + +size_t ZSTD_compressBlock_greedy_dedicatedDictSearch( + ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], + void const* src, size_t srcSize) +{ + return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, search_hashChain, 0, ZSTD_dedicatedDictSearch); +} + + FORCE_INLINE_TEMPLATE size_t ZSTD_compressBlock_lazy_extDict_generic( ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], const void* src, size_t srcSize, @@ -966,15 +1240,15 @@ #endif while (ip < ilimit) { size_t matchLength=0; size_t offset=0; const BYTE* start=ip+1; - U32 current = (U32)(ip-base); + U32 curr = (U32)(ip-base); /* check repCode */ - { const U32 windowLow = ZSTD_getLowestMatchIndex(ms, current+1, windowLog); - const U32 repIndex = (U32)(current+1 - offset_1); + { const U32 windowLow = ZSTD_getLowestMatchIndex(ms, curr+1, windowLog); + const U32 repIndex = (U32)(curr+1 - offset_1); const BYTE* const repBase = repIndex < dictLimit ? dictBase : base; const BYTE* const repMatch = repBase + repIndex; if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > windowLow)) /* intentional overflow */ if (MEM_read32(ip+1) == MEM_read32(repMatch)) { /* repcode detected we should take it */ @@ -997,15 +1271,15 @@ /* let's try to find a better solution */ if (depth>=1) while (ip<ilimit) { ip ++; - current++; + curr++; /* check repCode */ if (offset) { - const U32 windowLow = ZSTD_getLowestMatchIndex(ms, current, windowLog); - const U32 repIndex = (U32)(current - offset_1); + const U32 windowLow = ZSTD_getLowestMatchIndex(ms, curr, windowLog); + const U32 repIndex = (U32)(curr - offset_1); const BYTE* const repBase = repIndex < dictLimit ? dictBase : base; const BYTE* const repMatch = repBase + repIndex; if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > windowLow)) /* intentional overflow */ if (MEM_read32(ip) == MEM_read32(repMatch)) { /* repcode detected */ @@ -1028,14 +1302,14 @@ } } /* let's find an even better one */ if ((depth==2) && (ip<ilimit)) { ip ++; - current++; + curr++; /* check repCode */ if (offset) { - const U32 windowLow = ZSTD_getLowestMatchIndex(ms, current, windowLog); - const U32 repIndex = (U32)(current - offset_1); + const U32 windowLow = ZSTD_getLowestMatchIndex(ms, curr, windowLog); + const U32 repIndex = (U32)(curr - offset_1); const BYTE* const repBase = repIndex < dictLimit ? dictBase : base; const BYTE* const repMatch = repBase + repIndex; if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > windowLow)) /* intentional overflow */ if (MEM_read32(ip) == MEM_read32(repMatch)) { /* repcode detected */