zstd_lazy.c
1094 lines
| 48.9 KiB
| text/x-c
|
CLexer
|
r37513 | /* | ||
* Copyright (c) 2016-present, Yann Collet, Facebook, Inc. | ||||
* All rights reserved. | ||||
* | ||||
* This source code is licensed under both the BSD-style license (found in the | ||||
* LICENSE file in the root directory of this source tree) and the GPLv2 (found | ||||
* in the COPYING file in the root directory of this source tree). | ||||
* You may select, at your option, one of the above-listed licenses. | ||||
*/ | ||||
#include "zstd_compress_internal.h" | ||||
#include "zstd_lazy.h" | ||||
/*-************************************* | ||||
* Binary Tree search | ||||
***************************************/ | ||||
|
r40157 | static void | ||
ZSTD_updateDUBT(ZSTD_matchState_t* ms, | ||||
|
r37513 | const BYTE* ip, const BYTE* iend, | ||
U32 mls) | ||||
{ | ||||
|
r40157 | const ZSTD_compressionParameters* const cParams = &ms->cParams; | ||
|
r37513 | U32* const hashTable = ms->hashTable; | ||
U32 const hashLog = cParams->hashLog; | ||||
U32* const bt = ms->chainTable; | ||||
U32 const btLog = cParams->chainLog - 1; | ||||
U32 const btMask = (1 << btLog) - 1; | ||||
const BYTE* const base = ms->window.base; | ||||
U32 const target = (U32)(ip - base); | ||||
U32 idx = ms->nextToUpdate; | ||||
if (idx != target) | ||||
DEBUGLOG(7, "ZSTD_updateDUBT, from %u to %u (dictLimit:%u)", | ||||
idx, target, ms->window.dictLimit); | ||||
assert(ip + 8 <= iend); /* condition for ZSTD_hashPtr */ | ||||
(void)iend; | ||||
assert(idx >= ms->window.dictLimit); /* condition for valid base+idx */ | ||||
for ( ; idx < target ; idx++) { | ||||
size_t const h = ZSTD_hashPtr(base + idx, hashLog, mls); /* assumption : ip + 8 <= iend */ | ||||
U32 const matchIndex = hashTable[h]; | ||||
U32* const nextCandidatePtr = bt + 2*(idx&btMask); | ||||
U32* const sortMarkPtr = nextCandidatePtr + 1; | ||||
DEBUGLOG(8, "ZSTD_updateDUBT: insert %u", idx); | ||||
hashTable[h] = idx; /* Update Hash Table */ | ||||
*nextCandidatePtr = matchIndex; /* update BT like a chain */ | ||||
*sortMarkPtr = ZSTD_DUBT_UNSORTED_MARK; | ||||
} | ||||
ms->nextToUpdate = target; | ||||
} | ||||
/** ZSTD_insertDUBT1() : | ||||
* sort one already inserted but unsorted position | ||||
* assumption : current >= btlow == (current - btmask) | ||||
* doesn't fail */ | ||||
|
r40157 | static void | ||
ZSTD_insertDUBT1(ZSTD_matchState_t* ms, | ||||
|
r37513 | U32 current, const BYTE* inputEnd, | ||
|
r40157 | U32 nbCompares, U32 btLow, const ZSTD_dictMode_e dictMode) | ||
|
r37513 | { | ||
|
r40157 | const ZSTD_compressionParameters* const cParams = &ms->cParams; | ||
|
r37513 | U32* const bt = ms->chainTable; | ||
U32 const btLog = cParams->chainLog - 1; | ||||
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 dictEnd = dictBase + dictLimit; | ||||
const BYTE* const prefixStart = base + dictLimit; | ||||
const BYTE* match; | ||||
U32* smallerPtr = bt + 2*(current&btMask); | ||||
U32* largerPtr = smallerPtr + 1; | ||||
U32 matchIndex = *smallerPtr; | ||||
U32 dummy32; /* to be nullified at the end */ | ||||
U32 const windowLow = ms->window.lowLimit; | ||||
DEBUGLOG(8, "ZSTD_insertDUBT1(%u) (dictLimit=%u, lowLimit=%u)", | ||||
current, dictLimit, windowLow); | ||||
assert(current >= 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); | ||||
|
r40157 | if ( (dictMode != ZSTD_extDict) | ||
|
r37513 | || (matchIndex+matchLength >= dictLimit) /* both in current segment*/ | ||
|| (current < dictLimit) /* both in extDict */) { | ||||
|
r40157 | const BYTE* const mBase = ( (dictMode != ZSTD_extDict) | ||
|| (matchIndex+matchLength >= dictLimit)) ? | ||||
base : dictBase; | ||||
|
r37513 | assert( (matchIndex+matchLength >= dictLimit) /* might be wrong if extDict is incorrectly set to 0 */ | ||
|| (current < 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; /* to prepare for next usage of match[matchLength] */ | ||||
} | ||||
DEBUGLOG(8, "ZSTD_insertDUBT1: comparing %u with %u : found %u common bytes ", | ||||
current, 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 */ | ||||
} | ||||
if (match[matchLength] < ip[matchLength]) { /* necessarily within buffer */ | ||||
/* match is smaller than current */ | ||||
*smallerPtr = matchIndex; /* update smaller idx */ | ||||
commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */ | ||||
if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop searching */ | ||||
DEBUGLOG(8, "ZSTD_insertDUBT1: %u (>btLow=%u) is smaller : next => %u", | ||||
matchIndex, btLow, nextPtr[1]); | ||||
smallerPtr = nextPtr+1; /* new "candidate" => larger than match, which was smaller than target */ | ||||
matchIndex = nextPtr[1]; /* new matchIndex, larger than previous and closer to current */ | ||||
} else { | ||||
/* match is larger than current */ | ||||
*largerPtr = matchIndex; | ||||
commonLengthLarger = matchLength; | ||||
if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop searching */ | ||||
DEBUGLOG(8, "ZSTD_insertDUBT1: %u (>btLow=%u) is larger => %u", | ||||
matchIndex, btLow, nextPtr[0]); | ||||
largerPtr = nextPtr; | ||||
matchIndex = nextPtr[0]; | ||||
} } | ||||
*smallerPtr = *largerPtr = 0; | ||||
} | ||||
|
r40157 | static size_t | ||
ZSTD_DUBT_findBetterDictMatch ( | ||||
ZSTD_matchState_t* ms, | ||||
const BYTE* const ip, const BYTE* const iend, | ||||
size_t* offsetPtr, | ||||
U32 nbCompares, | ||||
U32 const mls, | ||||
const ZSTD_dictMode_e dictMode) | ||||
|
r37513 | { | ||
|
r40157 | const ZSTD_matchState_t * const dms = ms->dictMatchState; | ||
const ZSTD_compressionParameters* const dmsCParams = &dms->cParams; | ||||
const U32 * const dictHashTable = dms->hashTable; | ||||
U32 const hashLog = dmsCParams->hashLog; | ||||
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); | ||||
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; | ||||
U32* const dictBt = dms->chainTable; | ||||
U32 const btLog = dmsCParams->chainLog - 1; | ||||
U32 const btMask = (1 << btLog) - 1; | ||||
U32 const btLow = (btMask >= dictHighLimit - dictLowLimit) ? dictLowLimit : dictHighLimit - btMask; | ||||
size_t commonLengthSmaller=0, commonLengthLarger=0, bestLength=0; | ||||
U32 matchEndIdx = current+8+1; | ||||
(void)dictMode; | ||||
assert(dictMode == ZSTD_dictMatchState); | ||||
while (nbCompares-- && (dictMatchIndex > dictLowLimit)) { | ||||
U32* const nextPtr = dictBt + 2*(dictMatchIndex & btMask); | ||||
size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ | ||||
const BYTE* match = dictBase + dictMatchIndex; | ||||
matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iend, dictEnd, prefixStart); | ||||
if (dictMatchIndex+matchLength >= dictHighLimit) | ||||
match = base + dictMatchIndex + dictIndexDelta; /* to prepare for next usage of match[matchLength] */ | ||||
if (matchLength > bestLength) { | ||||
U32 matchIndex = dictMatchIndex + dictIndexDelta; | ||||
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)) ) { | ||||
DEBUGLOG(2, "ZSTD_DUBT_findBestDictMatch(%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; | ||||
} | ||||
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) */ | ||||
} | ||||
} | ||||
DEBUGLOG(2, "matchLength:%6zu, match:%p, prefixStart:%p, ip:%p", matchLength, match, prefixStart, ip); | ||||
if (match[matchLength] < ip[matchLength]) { | ||||
if (dictMatchIndex <= btLow) { break; } /* beyond tree size, stop the search */ | ||||
commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */ | ||||
dictMatchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to current) */ | ||||
} else { | ||||
/* match is larger than current */ | ||||
if (dictMatchIndex <= btLow) { break; } /* beyond tree size, stop the search */ | ||||
commonLengthLarger = matchLength; | ||||
dictMatchIndex = nextPtr[0]; | ||||
} | ||||
} | ||||
if (bestLength >= MINMATCH) { | ||||
U32 const mIndex = current - ((U32)*offsetPtr - ZSTD_REP_MOVE); (void)mIndex; | ||||
DEBUGLOG(2, "ZSTD_DUBT_findBestDictMatch(%u) : found match of length %u and offsetCode %u (pos %u)", | ||||
current, (U32)bestLength, (U32)*offsetPtr, mIndex); | ||||
} | ||||
return bestLength; | ||||
} | ||||
static size_t | ||||
ZSTD_DUBT_findBestMatch(ZSTD_matchState_t* ms, | ||||
const BYTE* const ip, const BYTE* const iend, | ||||
size_t* offsetPtr, | ||||
U32 const mls, | ||||
const ZSTD_dictMode_e dictMode) | ||||
{ | ||||
const ZSTD_compressionParameters* const cParams = &ms->cParams; | ||||
|
r37513 | U32* const hashTable = ms->hashTable; | ||
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 = ms->window.lowLimit; | ||||
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 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); | ||||
assert(ip <= iend-8); /* required for h calculation */ | ||||
/* reach end of unsorted candidates list */ | ||||
while ( (matchIndex > unsortLimit) | ||||
&& (*unsortedMark == ZSTD_DUBT_UNSORTED_MARK) | ||||
&& (nbCandidates > 1) ) { | ||||
DEBUGLOG(8, "ZSTD_DUBT_findBestMatch: candidate %u is unsorted", | ||||
matchIndex); | ||||
*unsortedMark = previousCandidate; | ||||
previousCandidate = matchIndex; | ||||
matchIndex = *nextCandidate; | ||||
nextCandidate = bt + 2*(matchIndex&btMask); | ||||
unsortedMark = bt + 2*(matchIndex&btMask) + 1; | ||||
nbCandidates --; | ||||
} | ||||
if ( (matchIndex > unsortLimit) | ||||
&& (*unsortedMark==ZSTD_DUBT_UNSORTED_MARK) ) { | ||||
DEBUGLOG(7, "ZSTD_DUBT_findBestMatch: nullify last unsorted candidate %u", | ||||
matchIndex); | ||||
*nextCandidate = *unsortedMark = 0; /* nullify next candidate if it's still unsorted (note : simplification, detrimental to compression ratio, beneficial for speed) */ | ||||
} | ||||
/* batch sort stacked candidates */ | ||||
matchIndex = previousCandidate; | ||||
while (matchIndex) { /* will end on matchIndex == 0 */ | ||||
U32* const nextCandidateIdxPtr = bt + 2*(matchIndex&btMask) + 1; | ||||
U32 const nextCandidateIdx = *nextCandidateIdxPtr; | ||||
|
r40157 | ZSTD_insertDUBT1(ms, matchIndex, iend, | ||
nbCandidates, unsortLimit, dictMode); | ||||
|
r37513 | matchIndex = nextCandidateIdx; | ||
nbCandidates++; | ||||
} | ||||
/* find longest match */ | ||||
{ 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 dummy32; /* to be nullified at the end */ | ||||
size_t bestLength = 0; | ||||
matchIndex = hashTable[h]; | ||||
hashTable[h] = current; /* 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; | ||||
|
r40157 | if ((dictMode != ZSTD_extDict) || (matchIndex+matchLength >= dictLimit)) { | ||
|
r37513 | match = base + 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; /* to prepare for next usage of match[matchLength] */ | ||||
} | ||||
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 (ip+matchLength == iend) { /* equal : no way to know if inf or sup */ | ||||
break; /* drop, to guarantee consistency (miss a little bit of compression) */ | ||||
} | ||||
} | ||||
if (match[matchLength] < ip[matchLength]) { | ||||
/* match is smaller than current */ | ||||
*smallerPtr = matchIndex; /* update smaller idx */ | ||||
commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */ | ||||
if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop the search */ | ||||
smallerPtr = nextPtr+1; /* new "smaller" => larger of match */ | ||||
matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to current) */ | ||||
} else { | ||||
/* match is larger than current */ | ||||
*largerPtr = matchIndex; | ||||
commonLengthLarger = matchLength; | ||||
if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop the search */ | ||||
largerPtr = nextPtr; | ||||
matchIndex = nextPtr[0]; | ||||
} } | ||||
*smallerPtr = *largerPtr = 0; | ||||
|
r40157 | if (dictMode == ZSTD_dictMatchState && nbCompares) { | ||
bestLength = ZSTD_DUBT_findBetterDictMatch(ms, ip, iend, offsetPtr, nbCompares, mls, dictMode); | ||||
} | ||||
|
r37513 | assert(matchEndIdx > current+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; | ||||
DEBUGLOG(8, "ZSTD_DUBT_findBestMatch(%u) : found match of length %u and offsetCode %u (pos %u)", | ||||
current, (U32)bestLength, (U32)*offsetPtr, mIndex); | ||||
} | ||||
return bestLength; | ||||
} | ||||
} | ||||
/** ZSTD_BtFindBestMatch() : Tree updater, providing best match */ | ||||
|
r40157 | FORCE_INLINE_TEMPLATE size_t | ||
ZSTD_BtFindBestMatch( ZSTD_matchState_t* ms, | ||||
const BYTE* const ip, const BYTE* const iLimit, | ||||
size_t* offsetPtr, | ||||
const U32 mls /* template */, | ||||
const ZSTD_dictMode_e dictMode) | ||||
|
r37513 | { | ||
DEBUGLOG(7, "ZSTD_BtFindBestMatch"); | ||||
if (ip < ms->window.base + ms->nextToUpdate) return 0; /* skipped area */ | ||||
|
r40157 | ZSTD_updateDUBT(ms, ip, iLimit, mls); | ||
return ZSTD_DUBT_findBestMatch(ms, ip, iLimit, offsetPtr, mls, dictMode); | ||||
|
r37513 | } | ||
|
r40157 | static size_t | ||
ZSTD_BtFindBestMatch_selectMLS ( ZSTD_matchState_t* ms, | ||||
const BYTE* ip, const BYTE* const iLimit, | ||||
size_t* offsetPtr) | ||||
|
r37513 | { | ||
|
r40157 | switch(ms->cParams.searchLength) | ||
|
r37513 | { | ||
default : /* includes case 3 */ | ||||
|
r40157 | case 4 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 4, ZSTD_noDict); | ||
case 5 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 5, ZSTD_noDict); | ||||
|
r37513 | case 7 : | ||
|
r40157 | case 6 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 6, ZSTD_noDict); | ||
|
r37513 | } | ||
} | ||||
|
r40157 | static size_t ZSTD_BtFindBestMatch_dictMatchState_selectMLS ( | ||
ZSTD_matchState_t* ms, | ||||
const BYTE* ip, const BYTE* const iLimit, | ||||
size_t* offsetPtr) | ||||
|
r37513 | { | ||
|
r40157 | switch(ms->cParams.searchLength) | ||
{ | ||||
default : /* includes case 3 */ | ||||
case 4 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 4, ZSTD_dictMatchState); | ||||
case 5 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 5, ZSTD_dictMatchState); | ||||
case 7 : | ||||
case 6 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 6, ZSTD_dictMatchState); | ||||
} | ||||
|
r37513 | } | ||
|
r40157 | static size_t ZSTD_BtFindBestMatch_extDict_selectMLS ( | ||
ZSTD_matchState_t* ms, | ||||
|
r37513 | const BYTE* ip, const BYTE* const iLimit, | ||
size_t* offsetPtr) | ||||
{ | ||||
|
r40157 | switch(ms->cParams.searchLength) | ||
|
r37513 | { | ||
default : /* includes case 3 */ | ||||
|
r40157 | case 4 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 4, ZSTD_extDict); | ||
case 5 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 5, ZSTD_extDict); | ||||
|
r37513 | case 7 : | ||
|
r40157 | case 6 : return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, 6, ZSTD_extDict); | ||
|
r37513 | } | ||
} | ||||
/* ********************************* | ||||
* Hash Chain | ||||
***********************************/ | ||||
#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( | ||||
|
r40157 | ZSTD_matchState_t* ms, | ||
const ZSTD_compressionParameters* const cParams, | ||||
|
r37513 | const BYTE* ip, U32 const mls) | ||
{ | ||||
U32* const hashTable = ms->hashTable; | ||||
const U32 hashLog = cParams->hashLog; | ||||
U32* const chainTable = ms->chainTable; | ||||
const U32 chainMask = (1 << cParams->chainLog) - 1; | ||||
const BYTE* const base = ms->window.base; | ||||
const U32 target = (U32)(ip - base); | ||||
U32 idx = ms->nextToUpdate; | ||||
while(idx < target) { /* catch up */ | ||||
size_t const h = ZSTD_hashPtr(base+idx, hashLog, mls); | ||||
NEXT_IN_CHAIN(idx, chainMask) = hashTable[h]; | ||||
hashTable[h] = idx; | ||||
idx++; | ||||
} | ||||
ms->nextToUpdate = target; | ||||
return hashTable[ZSTD_hashPtr(ip, hashLog, mls)]; | ||||
} | ||||
|
r40157 | 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.searchLength); | ||||
|
r37513 | } | ||
/* inlining is important to hardwire a hot branch (template emulation) */ | ||||
FORCE_INLINE_TEMPLATE | ||||
size_t ZSTD_HcFindBestMatch_generic ( | ||||
|
r40157 | ZSTD_matchState_t* ms, | ||
|
r37513 | const BYTE* const ip, const BYTE* const iLimit, | ||
size_t* offsetPtr, | ||||
|
r40157 | const U32 mls, const ZSTD_dictMode_e dictMode) | ||
|
r37513 | { | ||
|
r40157 | const ZSTD_compressionParameters* const cParams = &ms->cParams; | ||
|
r37513 | U32* const chainTable = ms->chainTable; | ||
const U32 chainSize = (1 << cParams->chainLog); | ||||
const U32 chainMask = chainSize-1; | ||||
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 lowLimit = ms->window.lowLimit; | ||||
const U32 current = (U32)(ip-base); | ||||
const U32 minChain = current > chainSize ? current - chainSize : 0; | ||||
U32 nbAttempts = 1U << cParams->searchLog; | ||||
size_t ml=4-1; | ||||
/* HC4 match finder */ | ||||
U32 matchIndex = ZSTD_insertAndFindFirstIndex_internal(ms, cParams, ip, mls); | ||||
for ( ; (matchIndex>lowLimit) & (nbAttempts>0) ; nbAttempts--) { | ||||
size_t currentMl=0; | ||||
|
r40157 | if ((dictMode != ZSTD_extDict) || matchIndex >= dictLimit) { | ||
|
r37513 | const BYTE* const match = base + matchIndex; | ||
if (match[ml] == ip[ml]) /* potentially better */ | ||||
currentMl = ZSTD_count(ip, match, iLimit); | ||||
} else { | ||||
const BYTE* const match = dictBase + matchIndex; | ||||
assert(match+4 <= dictEnd); | ||||
if (MEM_read32(match) == MEM_read32(ip)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */ | ||||
currentMl = ZSTD_count_2segments(ip+4, match+4, iLimit, dictEnd, prefixStart) + 4; | ||||
} | ||||
/* save best solution */ | ||||
if (currentMl > ml) { | ||||
ml = currentMl; | ||||
*offsetPtr = current - 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); | ||||
} | ||||
|
r40157 | if (dictMode == ZSTD_dictMatchState) { | ||
const ZSTD_matchState_t* const dms = ms->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; | ||||
const BYTE* const dmsEnd = dms->window.nextSrc; | ||||
const U32 dmsSize = (U32)(dmsEnd - dmsBase); | ||||
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--) { | ||||
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; | ||||
if (ip+currentMl == iLimit) break; /* best possible, avoids read overflow on next attempt */ | ||||
} | ||||
if (matchIndex <= dmsMinChain) break; | ||||
matchIndex = dmsChainTable[matchIndex & dmsChainMask]; | ||||
} | ||||
} | ||||
|
r37513 | return ml; | ||
} | ||||
FORCE_INLINE_TEMPLATE size_t ZSTD_HcFindBestMatch_selectMLS ( | ||||
|
r40157 | ZSTD_matchState_t* ms, | ||
|
r37513 | const BYTE* ip, const BYTE* const iLimit, | ||
size_t* offsetPtr) | ||||
{ | ||||
|
r40157 | switch(ms->cParams.searchLength) | ||
|
r37513 | { | ||
default : /* includes case 3 */ | ||||
|
r40157 | case 4 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 4, ZSTD_noDict); | ||
case 5 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 5, ZSTD_noDict); | ||||
|
r37513 | case 7 : | ||
|
r40157 | case 6 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 6, ZSTD_noDict); | ||
} | ||||
} | ||||
static size_t ZSTD_HcFindBestMatch_dictMatchState_selectMLS ( | ||||
ZSTD_matchState_t* ms, | ||||
const BYTE* ip, const BYTE* const iLimit, | ||||
size_t* offsetPtr) | ||||
{ | ||||
switch(ms->cParams.searchLength) | ||||
{ | ||||
default : /* includes case 3 */ | ||||
case 4 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 4, ZSTD_dictMatchState); | ||||
case 5 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 5, ZSTD_dictMatchState); | ||||
case 7 : | ||||
case 6 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 6, ZSTD_dictMatchState); | ||||
|
r37513 | } | ||
} | ||||
FORCE_INLINE_TEMPLATE size_t ZSTD_HcFindBestMatch_extDict_selectMLS ( | ||||
|
r40157 | ZSTD_matchState_t* ms, | ||
|
r37513 | const BYTE* ip, const BYTE* const iLimit, | ||
|
r40157 | size_t* offsetPtr) | ||
|
r37513 | { | ||
|
r40157 | switch(ms->cParams.searchLength) | ||
|
r37513 | { | ||
default : /* includes case 3 */ | ||||
|
r40157 | case 4 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 4, ZSTD_extDict); | ||
case 5 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 5, ZSTD_extDict); | ||||
|
r37513 | case 7 : | ||
|
r40157 | case 6 : return ZSTD_HcFindBestMatch_generic(ms, ip, iLimit, offsetPtr, 6, ZSTD_extDict); | ||
|
r37513 | } | ||
} | ||||
/* ******************************* | ||||
* Common parser - lazy strategy | ||||
*********************************/ | ||||
FORCE_INLINE_TEMPLATE | ||||
size_t ZSTD_compressBlock_lazy_generic( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, | ||||
U32 rep[ZSTD_REP_NUM], | ||||
const void* src, size_t srcSize, | ||||
|
r40157 | const U32 searchMethod, const U32 depth, | ||
ZSTD_dictMode_e const dictMode) | ||||
|
r37513 | { | ||
const BYTE* const istart = (const BYTE*)src; | ||||
const BYTE* ip = istart; | ||||
const BYTE* anchor = istart; | ||||
const BYTE* const iend = istart + srcSize; | ||||
const BYTE* const ilimit = iend - 8; | ||||
|
r40157 | const BYTE* const base = ms->window.base; | ||
const U32 prefixLowestIndex = ms->window.dictLimit; | ||||
const BYTE* const prefixLowest = base + prefixLowestIndex; | ||||
|
r37513 | |||
typedef size_t (*searchMax_f)( | ||||
|
r40157 | ZSTD_matchState_t* ms, | ||
|
r37513 | const BYTE* ip, const BYTE* iLimit, size_t* offsetPtr); | ||
|
r40157 | searchMax_f const searchMax = dictMode == ZSTD_dictMatchState ? | ||
(searchMethod ? ZSTD_BtFindBestMatch_dictMatchState_selectMLS : ZSTD_HcFindBestMatch_dictMatchState_selectMLS) : | ||||
(searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS); | ||||
|
r37513 | U32 offset_1 = rep[0], offset_2 = rep[1], savedOffset=0; | ||
|
r40157 | 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 ? | ||||
prefixLowestIndex - (U32)(dictEnd - dictBase) : | ||||
0; | ||||
const U32 dictAndPrefixLength = (U32)(ip - prefixLowest + dictEnd - dictLowest); | ||||
|
r37513 | /* init */ | ||
|
r40157 | ip += (dictAndPrefixLength == 0); | ||
|
r37513 | ms->nextToUpdate3 = ms->nextToUpdate; | ||
|
r40157 | if (dictMode == ZSTD_noDict) { | ||
U32 const maxRep = (U32)(ip - prefixLowest); | ||||
|
r37513 | if (offset_2 > maxRep) savedOffset = offset_2, offset_2 = 0; | ||
if (offset_1 > maxRep) savedOffset = offset_1, offset_1 = 0; | ||||
} | ||||
|
r40157 | if (dictMode == ZSTD_dictMatchState) { | ||
/* dictMatchState repCode checks don't currently handle repCode == 0 | ||||
* disabling. */ | ||||
assert(offset_1 <= dictAndPrefixLength); | ||||
assert(offset_2 <= dictAndPrefixLength); | ||||
} | ||||
|
r37513 | |||
/* Match Loop */ | ||||
while (ip < ilimit) { | ||||
size_t matchLength=0; | ||||
size_t offset=0; | ||||
const BYTE* start=ip+1; | ||||
/* check repCode */ | ||||
|
r40157 | if (dictMode == ZSTD_dictMatchState) { | ||
const U32 repIndex = (U32)(ip - base) + 1 - offset_1; | ||||
const BYTE* repMatch = (dictMode == ZSTD_dictMatchState | ||||
&& repIndex < prefixLowestIndex) ? | ||||
dictBase + (repIndex - dictIndexDelta) : | ||||
base + repIndex; | ||||
if (((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) | ||||
&& (MEM_read32(repMatch) == MEM_read32(ip+1)) ) { | ||||
const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend; | ||||
matchLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4; | ||||
if (depth==0) goto _storeSequence; | ||||
} | ||||
} | ||||
if ( dictMode == ZSTD_noDict | ||||
&& ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1)))) { | ||||
|
r37513 | matchLength = ZSTD_count(ip+1+4, ip+1+4-offset_1, iend) + 4; | ||
if (depth==0) goto _storeSequence; | ||||
} | ||||
/* first search (depth 0) */ | ||||
|
r40157 | { size_t offsetFound = 999999999; | ||
size_t const ml2 = searchMax(ms, ip, iend, &offsetFound); | ||||
|
r37513 | if (ml2 > matchLength) | ||
matchLength = ml2, start = ip, offset=offsetFound; | ||||
} | ||||
if (matchLength < 4) { | ||||
ip += ((ip-anchor) >> kSearchStrength) + 1; /* jump faster over incompressible sections */ | ||||
continue; | ||||
} | ||||
/* let's try to find a better solution */ | ||||
if (depth>=1) | ||||
while (ip<ilimit) { | ||||
ip ++; | ||||
|
r40157 | if ( (dictMode == ZSTD_noDict) | ||
&& (offset) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) { | ||||
|
r37513 | size_t const mlRep = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4; | ||
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; | ||||
} | ||||
|
r40157 | if (dictMode == ZSTD_dictMatchState) { | ||
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 */) | ||||
&& (MEM_read32(repMatch) == MEM_read32(ip)) ) { | ||||
const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend; | ||||
size_t const mlRep = ZSTD_count_2segments(ip+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4; | ||||
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; | ||||
} | ||||
} | ||||
{ size_t offset2=999999999; | ||||
size_t const ml2 = searchMax(ms, ip, iend, &offset2); | ||||
|
r37513 | int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */ | ||
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 4); | ||||
if ((ml2 >= 4) && (gain2 > gain1)) { | ||||
matchLength = ml2, offset = offset2, start = ip; | ||||
continue; /* search a better one */ | ||||
} } | ||||
/* let's find an even better one */ | ||||
if ((depth==2) && (ip<ilimit)) { | ||||
ip ++; | ||||
|
r40157 | if ( (dictMode == ZSTD_noDict) | ||
&& (offset) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) { | ||||
size_t const mlRep = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4; | ||||
int const gain2 = (int)(mlRep * 4); | ||||
|
r37513 | int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1); | ||
|
r40157 | if ((mlRep >= 4) && (gain2 > gain1)) | ||
matchLength = mlRep, offset = 0, start = ip; | ||||
|
r37513 | } | ||
|
r40157 | if (dictMode == ZSTD_dictMatchState) { | ||
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 */) | ||||
&& (MEM_read32(repMatch) == MEM_read32(ip)) ) { | ||||
const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend; | ||||
size_t const mlRep = ZSTD_count_2segments(ip+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4; | ||||
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; | ||||
} | ||||
} | ||||
{ size_t offset2=999999999; | ||||
size_t const ml2 = searchMax(ms, ip, iend, &offset2); | ||||
|
r37513 | int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */ | ||
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 7); | ||||
if ((ml2 >= 4) && (gain2 > gain1)) { | ||||
matchLength = ml2, offset = offset2, start = ip; | ||||
continue; | ||||
} } } | ||||
break; /* nothing found : store previous solution */ | ||||
} | ||||
/* NOTE: | ||||
* start[-offset+ZSTD_REP_MOVE-1] is undefined behavior. | ||||
* (-offset+ZSTD_REP_MOVE-1) is unsigned, and is added to start, which | ||||
* overflows the pointer, which is undefined behavior. | ||||
*/ | ||||
/* catch up */ | ||||
if (offset) { | ||||
|
r40157 | 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) { | ||||
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 */ | ||||
} | ||||
|
r37513 | offset_2 = offset_1; offset_1 = (U32)(offset - ZSTD_REP_MOVE); | ||
} | ||||
/* store sequence */ | ||||
_storeSequence: | ||||
{ size_t const litLength = start - anchor; | ||||
ZSTD_storeSeq(seqStore, litLength, anchor, (U32)offset, matchLength-MINMATCH); | ||||
anchor = ip = start + matchLength; | ||||
} | ||||
/* check immediate repcode */ | ||||
|
r40157 | if (dictMode == ZSTD_dictMatchState) { | ||
while (ip <= ilimit) { | ||||
U32 const current2 = (U32)(ip-base); | ||||
U32 const repIndex = current2 - offset_2; | ||||
const BYTE* repMatch = dictMode == ZSTD_dictMatchState | ||||
&& 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; | ||||
matchLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd2, prefixLowest) + 4; | ||||
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap offset_2 <=> offset_1 */ | ||||
ZSTD_storeSeq(seqStore, 0, anchor, 0, matchLength-MINMATCH); | ||||
ip += matchLength; | ||||
anchor = ip; | ||||
continue; | ||||
} | ||||
break; | ||||
} | ||||
} | ||||
if (dictMode == ZSTD_noDict) { | ||||
while ( ((ip <= ilimit) & (offset_2>0)) | ||||
&& (MEM_read32(ip) == MEM_read32(ip - offset_2)) ) { | ||||
/* store sequence */ | ||||
matchLength = ZSTD_count(ip+4, ip+4-offset_2, iend) + 4; | ||||
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap repcodes */ | ||||
ZSTD_storeSeq(seqStore, 0, anchor, 0, matchLength-MINMATCH); | ||||
ip += matchLength; | ||||
anchor = ip; | ||||
continue; /* faster when present ... (?) */ | ||||
} } } | ||||
|
r37513 | |||
/* Save reps for next block */ | ||||
rep[0] = offset_1 ? offset_1 : savedOffset; | ||||
rep[1] = offset_2 ? offset_2 : savedOffset; | ||||
/* Return the last literals size */ | ||||
return iend - anchor; | ||||
} | ||||
size_t ZSTD_compressBlock_btlazy2( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
|
r40157 | void const* src, size_t srcSize) | ||
|
r37513 | { | ||
|
r40157 | return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, 1, 2, ZSTD_noDict); | ||
|
r37513 | } | ||
size_t ZSTD_compressBlock_lazy2( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
|
r40157 | void const* src, size_t srcSize) | ||
|
r37513 | { | ||
|
r40157 | return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, 0, 2, ZSTD_noDict); | ||
|
r37513 | } | ||
size_t ZSTD_compressBlock_lazy( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
|
r40157 | void const* src, size_t srcSize) | ||
|
r37513 | { | ||
|
r40157 | return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, 0, 1, ZSTD_noDict); | ||
|
r37513 | } | ||
size_t ZSTD_compressBlock_greedy( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
|
r40157 | void const* src, size_t srcSize) | ||
{ | ||||
return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, 0, 0, ZSTD_noDict); | ||||
} | ||||
size_t ZSTD_compressBlock_btlazy2_dictMatchState( | ||||
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, 1, 2, ZSTD_dictMatchState); | ||||
} | ||||
size_t ZSTD_compressBlock_lazy2_dictMatchState( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
void const* src, size_t srcSize) | ||||
|
r37513 | { | ||
|
r40157 | return ZSTD_compressBlock_lazy_generic(ms, seqStore, rep, src, srcSize, 0, 2, ZSTD_dictMatchState); | ||
} | ||||
size_t ZSTD_compressBlock_lazy_dictMatchState( | ||||
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, 0, 1, ZSTD_dictMatchState); | ||||
} | ||||
size_t ZSTD_compressBlock_greedy_dictMatchState( | ||||
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, 0, 0, ZSTD_dictMatchState); | ||||
|
r37513 | } | ||
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, | ||||
const U32 searchMethod, const U32 depth) | ||||
{ | ||||
const BYTE* const istart = (const BYTE*)src; | ||||
const BYTE* ip = istart; | ||||
const BYTE* anchor = istart; | ||||
const BYTE* const iend = istart + srcSize; | ||||
const BYTE* const ilimit = iend - 8; | ||||
const BYTE* const base = ms->window.base; | ||||
const U32 dictLimit = ms->window.dictLimit; | ||||
const U32 lowestIndex = ms->window.lowLimit; | ||||
const BYTE* const prefixStart = base + dictLimit; | ||||
const BYTE* const dictBase = ms->window.dictBase; | ||||
const BYTE* const dictEnd = dictBase + dictLimit; | ||||
const BYTE* const dictStart = dictBase + lowestIndex; | ||||
typedef size_t (*searchMax_f)( | ||||
|
r40157 | ZSTD_matchState_t* ms, | ||
|
r37513 | const BYTE* ip, const BYTE* iLimit, size_t* offsetPtr); | ||
|
r40157 | searchMax_f searchMax = searchMethod ? ZSTD_BtFindBestMatch_extDict_selectMLS : ZSTD_HcFindBestMatch_extDict_selectMLS; | ||
|
r37513 | |||
U32 offset_1 = rep[0], offset_2 = rep[1]; | ||||
/* init */ | ||||
ms->nextToUpdate3 = ms->nextToUpdate; | ||||
ip += (ip == prefixStart); | ||||
/* Match Loop */ | ||||
while (ip < ilimit) { | ||||
size_t matchLength=0; | ||||
size_t offset=0; | ||||
const BYTE* start=ip+1; | ||||
U32 current = (U32)(ip-base); | ||||
/* check repCode */ | ||||
{ const U32 repIndex = (U32)(current+1 - offset_1); | ||||
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base; | ||||
const BYTE* const repMatch = repBase + repIndex; | ||||
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ | ||||
if (MEM_read32(ip+1) == MEM_read32(repMatch)) { | ||||
/* repcode detected we should take it */ | ||||
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend; | ||||
matchLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repEnd, prefixStart) + 4; | ||||
if (depth==0) goto _storeSequence; | ||||
} } | ||||
/* first search (depth 0) */ | ||||
|
r40157 | { size_t offsetFound = 999999999; | ||
size_t const ml2 = searchMax(ms, ip, iend, &offsetFound); | ||||
|
r37513 | if (ml2 > matchLength) | ||
matchLength = ml2, start = ip, offset=offsetFound; | ||||
} | ||||
if (matchLength < 4) { | ||||
ip += ((ip-anchor) >> kSearchStrength) + 1; /* jump faster over incompressible sections */ | ||||
continue; | ||||
} | ||||
/* let's try to find a better solution */ | ||||
if (depth>=1) | ||||
while (ip<ilimit) { | ||||
ip ++; | ||||
current++; | ||||
/* check repCode */ | ||||
if (offset) { | ||||
const U32 repIndex = (U32)(current - offset_1); | ||||
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base; | ||||
const BYTE* const repMatch = repBase + repIndex; | ||||
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ | ||||
if (MEM_read32(ip) == MEM_read32(repMatch)) { | ||||
/* repcode detected */ | ||||
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend; | ||||
size_t const repLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4; | ||||
int const gain2 = (int)(repLength * 3); | ||||
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1); | ||||
if ((repLength >= 4) && (gain2 > gain1)) | ||||
matchLength = repLength, offset = 0, start = ip; | ||||
} } | ||||
/* search match, depth 1 */ | ||||
|
r40157 | { size_t offset2=999999999; | ||
size_t const ml2 = searchMax(ms, ip, iend, &offset2); | ||||
|
r37513 | int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */ | ||
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 4); | ||||
if ((ml2 >= 4) && (gain2 > gain1)) { | ||||
matchLength = ml2, offset = offset2, start = ip; | ||||
continue; /* search a better one */ | ||||
} } | ||||
/* let's find an even better one */ | ||||
if ((depth==2) && (ip<ilimit)) { | ||||
ip ++; | ||||
current++; | ||||
/* check repCode */ | ||||
if (offset) { | ||||
const U32 repIndex = (U32)(current - offset_1); | ||||
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base; | ||||
const BYTE* const repMatch = repBase + repIndex; | ||||
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ | ||||
if (MEM_read32(ip) == MEM_read32(repMatch)) { | ||||
/* repcode detected */ | ||||
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend; | ||||
size_t const repLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4; | ||||
int const gain2 = (int)(repLength * 4); | ||||
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1); | ||||
if ((repLength >= 4) && (gain2 > gain1)) | ||||
matchLength = repLength, offset = 0, start = ip; | ||||
} } | ||||
/* search match, depth 2 */ | ||||
|
r40157 | { size_t offset2=999999999; | ||
size_t const ml2 = searchMax(ms, ip, iend, &offset2); | ||||
|
r37513 | int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */ | ||
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 7); | ||||
if ((ml2 >= 4) && (gain2 > gain1)) { | ||||
matchLength = ml2, offset = offset2, start = ip; | ||||
continue; | ||||
} } } | ||||
break; /* nothing found : store previous solution */ | ||||
} | ||||
/* catch up */ | ||||
if (offset) { | ||||
U32 const matchIndex = (U32)((start-base) - (offset - ZSTD_REP_MOVE)); | ||||
const BYTE* match = (matchIndex < dictLimit) ? dictBase + matchIndex : base + matchIndex; | ||||
const BYTE* const mStart = (matchIndex < dictLimit) ? dictStart : prefixStart; | ||||
while ((start>anchor) && (match>mStart) && (start[-1] == match[-1])) { start--; match--; matchLength++; } /* catch up */ | ||||
offset_2 = offset_1; offset_1 = (U32)(offset - ZSTD_REP_MOVE); | ||||
} | ||||
/* store sequence */ | ||||
_storeSequence: | ||||
{ size_t const litLength = start - anchor; | ||||
ZSTD_storeSeq(seqStore, litLength, anchor, (U32)offset, matchLength-MINMATCH); | ||||
anchor = ip = start + matchLength; | ||||
} | ||||
/* check immediate repcode */ | ||||
while (ip <= ilimit) { | ||||
const U32 repIndex = (U32)((ip-base) - offset_2); | ||||
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base; | ||||
const BYTE* const repMatch = repBase + repIndex; | ||||
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ | ||||
if (MEM_read32(ip) == MEM_read32(repMatch)) { | ||||
/* repcode detected we should take it */ | ||||
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend; | ||||
matchLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4; | ||||
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap offset history */ | ||||
ZSTD_storeSeq(seqStore, 0, anchor, 0, matchLength-MINMATCH); | ||||
ip += matchLength; | ||||
anchor = ip; | ||||
continue; /* faster when present ... (?) */ | ||||
} | ||||
break; | ||||
} } | ||||
/* Save reps for next block */ | ||||
rep[0] = offset_1; | ||||
rep[1] = offset_2; | ||||
/* Return the last literals size */ | ||||
return iend - anchor; | ||||
} | ||||
size_t ZSTD_compressBlock_greedy_extDict( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
|
r40157 | void const* src, size_t srcSize) | ||
|
r37513 | { | ||
|
r40157 | return ZSTD_compressBlock_lazy_extDict_generic(ms, seqStore, rep, src, srcSize, 0, 0); | ||
|
r37513 | } | ||
size_t ZSTD_compressBlock_lazy_extDict( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
|
r40157 | void const* src, size_t srcSize) | ||
|
r37513 | |||
{ | ||||
|
r40157 | return ZSTD_compressBlock_lazy_extDict_generic(ms, seqStore, rep, src, srcSize, 0, 1); | ||
|
r37513 | } | ||
size_t ZSTD_compressBlock_lazy2_extDict( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
|
r40157 | void const* src, size_t srcSize) | ||
|
r37513 | |||
{ | ||||
|
r40157 | return ZSTD_compressBlock_lazy_extDict_generic(ms, seqStore, rep, src, srcSize, 0, 2); | ||
|
r37513 | } | ||
size_t ZSTD_compressBlock_btlazy2_extDict( | ||||
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], | ||||
|
r40157 | void const* src, size_t srcSize) | ||
|
r37513 | |||
{ | ||||
|
r40157 | return ZSTD_compressBlock_lazy_extDict_generic(ms, seqStore, rep, src, srcSize, 1, 2); | ||
|
r37513 | } | ||