-/* ***********************
-* Hash Chain
-*************************/
-
-#define NEXT_IN_CHAIN(d, mask) chainTable[(d) & mask]
-
-/* Update chains up to ip (excluded)
- Assumption : always within prefix (ie. not within extDict) */
-FORCE_INLINE
-U32 ZSTD_insertAndFindFirstIndex (ZSTD_CCtx* zc, const BYTE* ip, U32 mls)
-{
- U32* const hashTable = zc->hashTable;
- const U32 hashLog = zc->params.cParams.hashLog;
- U32* const chainTable = zc->chainTable;
- const U32 chainMask = (1 << zc->params.cParams.chainLog) - 1;
- const BYTE* const base = zc->base;
- const U32 target = (U32)(ip - base);
- U32 idx = zc->nextToUpdate;
-
- while(idx < target) {
- size_t const h = ZSTD_hashPtr(base+idx, hashLog, mls);
- NEXT_IN_CHAIN(idx, chainMask) = hashTable[h];
- hashTable[h] = idx;
- idx++;
- }
-
- zc->nextToUpdate = target;
- return hashTable[ZSTD_hashPtr(ip, hashLog, mls)];
-}
-
-
-/* Update hashTable3 up to ip (excluded)
- Assumption : always within prefix (ie. not within extDict) */
-FORCE_INLINE
-U32 ZSTD_insertAndFindFirstIndexHash3 (ZSTD_CCtx* zc, const BYTE* ip)
-{
- U32* const hashTable3 = zc->hashTable3;
- U32 const hashLog3 = zc->hashLog3;
- const BYTE* const base = zc->base;
- U32 idx = zc->nextToUpdate3;
- const U32 target = zc->nextToUpdate3 = (U32)(ip - base);
- const size_t hash3 = ZSTD_hash3Ptr(ip, hashLog3);
-
- while(idx < target) {
- hashTable3[ZSTD_hash3Ptr(base+idx, hashLog3)] = idx;
- idx++;
- }
-
- return hashTable3[hash3];
-}
-
-
-FORCE_INLINE /* inlining is important to hardwire a hot branch (template emulation) */
-size_t ZSTD_HcFindBestMatch_generic (
- ZSTD_CCtx* zc, /* Index table will be updated */
- const BYTE* const ip, const BYTE* const iLimit,
- size_t* offsetPtr,
- const U32 maxNbAttempts, const U32 mls, const U32 extDict)
-{
- U32* const chainTable = zc->chainTable;
- const U32 chainSize = (1 << zc->params.cParams.chainLog);
- const U32 chainMask = chainSize-1;
- const BYTE* const base = zc->base;
- const BYTE* const dictBase = zc->dictBase;
- const U32 dictLimit = zc->dictLimit;
- const BYTE* const prefixStart = base + dictLimit;
- const BYTE* const dictEnd = dictBase + dictLimit;
- const U32 lowLimit = zc->lowLimit;
- const U32 current = (U32)(ip-base);
- const U32 minChain = current > chainSize ? current - chainSize : 0;
- int nbAttempts=maxNbAttempts;
- const U32 minMatch = (mls == 3) ? 3 : 4;
- size_t ml=minMatch-1;
-
-#if 0
- if (minMatch == 3) { /* HC3 match finder */
- U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3 (zc, ip);
- if (matchIndex3>lowLimit && current - matchIndex3<(1<<18)) {
- const BYTE* match;
- size_t currentMl=0;
- if ((!extDict) || matchIndex3 >= dictLimit) {
- match = base + matchIndex3;
- if (match[ml] == ip[ml]) currentMl = ZSTD_count(ip, match, iLimit); /* potentially better */
- } else {
- match = dictBase + matchIndex3;
- if (MEM_readMINMATCH(match, MINMATCH) == MEM_readMINMATCH(ip, MINMATCH)) /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
- currentMl = ZSTD_count_2segments(ip+MINMATCH, match+MINMATCH, iLimit, dictEnd, prefixStart) + MINMATCH;
- }
-
- /* save best solution */
- if (currentMl > ml) {
- ml = currentMl; *offsetPtr = ZSTD_REP_MOVE + current - matchIndex3;
- if (ip+currentMl == iLimit) return (ml>=MINMATCH) ? ml : 0; /* best possible, and avoid read overflow*/
- } }
- }
-#endif
-
- /* HC4 match finder */
- U32 matchIndex = ZSTD_insertAndFindFirstIndex (zc, ip, mls);
-
- for ( ; (matchIndex>lowLimit) && (nbAttempts) ; nbAttempts--) {
- const BYTE* match;
- size_t currentMl=0;
- if ((!extDict) || matchIndex >= dictLimit) {
- match = base + matchIndex;
- if (match[ml] == ip[ml]) /* potentially better */
- currentMl = ZSTD_count(ip, match, iLimit);
- } else {
- match = dictBase + matchIndex;
- if (MEM_readMINMATCH(match, minMatch) == MEM_readMINMATCH(ip, minMatch)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */
- currentMl = ZSTD_count_2segments(ip+minMatch, match+minMatch, iLimit, dictEnd, prefixStart) + minMatch;
- }
-
- /* save best solution */
- if (currentMl > ml) { ml = currentMl; *offsetPtr = ZSTD_REP_MOVE + current - matchIndex; if (ip+currentMl == iLimit) break; /* best possible, and avoid read overflow*/ }
-
- if (matchIndex <= minChain) break;
- matchIndex = NEXT_IN_CHAIN(matchIndex, chainMask);
- }
-
- return (ml>=minMatch) ? ml : 0;
-}
-
-
-FORCE_INLINE size_t ZSTD_HcFindBestMatch_selectMLS (
- ZSTD_CCtx* zc,
- const BYTE* ip, const BYTE* const iLimit,
- size_t* offsetPtr,
- const U32 maxNbAttempts, const U32 matchLengthSearch)
-{
- switch(matchLengthSearch)
- {
- case 3 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 3, 0);
- default :
- case 4 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 0);
- case 5 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 0);
- case 6 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 0);
- }
-}
-
-
-FORCE_INLINE size_t ZSTD_HcFindBestMatch_extDict_selectMLS (
- ZSTD_CCtx* zc,
- const BYTE* ip, const BYTE* const iLimit,
- size_t* offsetPtr,
- const U32 maxNbAttempts, const U32 matchLengthSearch)
-{
- switch(matchLengthSearch)
- {
- case 3 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 3, 1);
- default :
- case 4 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 1);
- case 5 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 1);
- case 6 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 1);
- }
-}
-
-
-
/*-*************************************
* Binary Tree search
***************************************/
U32* largerPtr = bt + 2*(current&btMask) + 1;
U32 matchEndIdx = current+8;
U32 dummy32; /* to be nullified at the end */
- const U32 minMatch = (mls == 3) ? 3 : 4;
- size_t bestLength = minMatch-1;
-
- if (minMatch == 3) { /* HC3 match finder */
- U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3 (zc, ip);
- if (matchIndex3>windowLow && (current - matchIndex3 < (1<<18))) {
- const BYTE* match;
- size_t currentMl=0;
- if ((!extDict) || matchIndex3 >= dictLimit) {
- match = base + matchIndex3;
- if (match[bestLength] == ip[bestLength]) currentMl = ZSTD_count(ip, match, iend);
- } else {
- match = dictBase + matchIndex3;
- if (MEM_readMINMATCH(match, MINMATCH) == MEM_readMINMATCH(ip, MINMATCH)) /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
- currentMl = ZSTD_count_2segments(ip+MINMATCH, match+MINMATCH, iend, dictEnd, prefixStart) + MINMATCH;
- }
-
- /* save best solution */
- if (currentMl > bestLength) {
- bestLength = currentMl, *offsetPtr = ZSTD_REP_MOVE + current - matchIndex3;
- if (ip+currentMl == iend) goto update; /* best possible, and avoid read overflow*/
- }
- } }
+ size_t bestLength = 0;
hashTable[h] = current; /* Update Hash Table */
*smallerPtr = *largerPtr = 0;
-update:
zc->nextToUpdate = (matchEndIdx > current + 8) ? matchEndIdx - 8 : current+1;
- return (bestLength>=minMatch) ? bestLength : 0;
+ return bestLength;
}
{
switch(matchLengthSearch)
{
- case 3 : return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 3);
default :
case 4 : return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4);
case 5 : return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5);
while (idx < target) idx += ZSTD_insertBt1(zc, base+idx, mls, iend, nbCompares, 1);
}
+
+
/** Tree updater, providing best match */
static size_t ZSTD_BtFindBestMatch_extDict (
ZSTD_CCtx* zc,
{
switch(matchLengthSearch)
{
- case 3 : return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 3);
default :
case 4 : return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4);
case 5 : return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5);
-/* *******************************
-* Greedy parser
-*********************************/
-FORCE_INLINE
-void ZSTD_compressBlock_greedy_generic(ZSTD_CCtx* ctx,
- const void* src, size_t srcSize)
-{
- seqStore_t* seqStorePtr = &(ctx->seqStore);
- 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 = ctx->base + ctx->dictLimit;
-
- const U32 maxSearches = 1 << ctx->params.cParams.searchLog;
- const U32 mls = ctx->params.cParams.searchLength;
- /* init */
- U32 rep[ZSTD_REP_INIT];
- for (U32 i=0; i<ZSTD_REP_INIT; i++)
- rep[i]=REPCODE_STARTVALUE;
-
- ZSTD_resetSeqStore(seqStorePtr);
- if ((ip-base) < REPCODE_STARTVALUE) ip = base + REPCODE_STARTVALUE;
-
- /* Match Loop */
- while (ip < ilimit) {
- size_t matchLength=0;
- size_t offset=0;
- const BYTE* start=ip+1;
-
- /* check repCode */
- if (MEM_read32(start) == MEM_read32(start - rep[0])) {
- /* repcode : we take it */
- matchLength = ZSTD_count(start+EQUAL_READ32, start+EQUAL_READ32-rep[0], iend) + EQUAL_READ32;
- goto _storeSequence;
- }
-
- /* first search (depth 0) */
- { size_t offsetFound = 99999999;
- size_t const ml2 = ZSTD_HcFindBestMatch_selectMLS(ctx, ip, iend, &offsetFound, maxSearches, mls);
- if (ml2 > matchLength)
- matchLength = ml2, start = ip, offset=offsetFound;
- }
-
- if (matchLength < EQUAL_READ32) {
- ip += ((ip-anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
- continue;
- }
+/* ***********************
+* Hash Chain
+*************************/
- /* catch up */
- while ((start>anchor) && (start>base+offset-ZSTD_REP_MOVE) && (start[-1] == start[-1-offset+ZSTD_REP_MOVE])) /* only search for offset within prefix */
- { start--; matchLength++; }
- rep[1] = rep[0]; rep[0] = (U32)(offset - ZSTD_REP_MOVE);
+#define NEXT_IN_CHAIN(d, mask) chainTable[(d) & mask]
-_storeSequence:
- /* store sequence */
- { size_t const litLength = start - anchor;
- ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, matchLength-MINMATCH);
- anchor = ip = start + matchLength;
- }
-
- /* check immediate repcode */
- while ( (ip <= ilimit)
- && (MEM_read32(ip) == MEM_read32(ip - rep[1])) ) {
- /* store sequence */
- matchLength = ZSTD_count(ip+EQUAL_READ32, ip+EQUAL_READ32-rep[1], iend) + EQUAL_READ32;
- offset = rep[1]; rep[1] = rep[0]; rep[0] = (U32)offset; /* swap offset history */
- ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength-MINMATCH);
- ip += matchLength;
- anchor = ip;
- continue; /* faster when present ... (?) */
- } }
+/* Update chains up to ip (excluded)
+ Assumption : always within prefix (ie. not within extDict) */
+FORCE_INLINE
+U32 ZSTD_insertAndFindFirstIndex (ZSTD_CCtx* zc, const BYTE* ip, U32 mls)
+{
+ U32* const hashTable = zc->hashTable;
+ const U32 hashLog = zc->params.cParams.hashLog;
+ U32* const chainTable = zc->chainTable;
+ const U32 chainMask = (1 << zc->params.cParams.chainLog) - 1;
+ const BYTE* const base = zc->base;
+ const U32 target = (U32)(ip - base);
+ U32 idx = zc->nextToUpdate;
- /* Last Literals */
- { size_t const lastLLSize = iend - anchor;
- memcpy(seqStorePtr->lit, anchor, lastLLSize);
- seqStorePtr->lit += lastLLSize;
- ZSTD_statsUpdatePrices(&seqStorePtr->stats, lastLLSize, anchor, 0, 0);
+ while(idx < target) {
+ size_t const h = ZSTD_hashPtr(base+idx, hashLog, mls);
+ NEXT_IN_CHAIN(idx, chainMask) = hashTable[h];
+ hashTable[h] = idx;
+ idx++;
}
+
+ zc->nextToUpdate = target;
+ return hashTable[ZSTD_hashPtr(ip, hashLog, mls)];
}
-FORCE_INLINE
-void ZSTD_compressBlock_greedy_extDict_generic(ZSTD_CCtx* ctx,
- const void* src, size_t srcSize)
+
+FORCE_INLINE /* inlining is important to hardwire a hot branch (template emulation) */
+size_t ZSTD_HcFindBestMatch_generic (
+ ZSTD_CCtx* zc, /* Index table will be updated */
+ const BYTE* const ip, const BYTE* const iLimit,
+ size_t* offsetPtr,
+ const U32 maxNbAttempts, const U32 mls, const U32 extDict)
{
- seqStore_t* seqStorePtr = &(ctx->seqStore);
- 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 = ctx->base;
- const U32 dictLimit = ctx->dictLimit;
+ U32* const chainTable = zc->chainTable;
+ const U32 chainSize = (1 << zc->params.cParams.chainLog);
+ const U32 chainMask = chainSize-1;
+ const BYTE* const base = zc->base;
+ const BYTE* const dictBase = zc->dictBase;
+ const U32 dictLimit = zc->dictLimit;
const BYTE* const prefixStart = base + dictLimit;
- const BYTE* const dictBase = ctx->dictBase;
- const BYTE* const dictEnd = dictBase + dictLimit;
- const BYTE* const dictStart = dictBase + ctx->lowLimit;
-
- const U32 maxSearches = 1 << ctx->params.cParams.searchLog;
- const U32 mls = ctx->params.cParams.searchLength;
-
- /* init */
- U32 rep[ZSTD_REP_INIT];
- for (U32 i=0; i<ZSTD_REP_INIT; i++)
- rep[i]=REPCODE_STARTVALUE;
+ const BYTE* const dictEnd = dictBase + dictLimit;
+ const U32 lowLimit = zc->lowLimit;
+ const U32 current = (U32)(ip-base);
+ const U32 minChain = current > chainSize ? current - chainSize : 0;
+ int nbAttempts=maxNbAttempts;
+ size_t ml=EQUAL_READ32-1;
- ZSTD_resetSeqStore(seqStorePtr);
- if ((ip - prefixStart) < REPCODE_STARTVALUE) ip += REPCODE_STARTVALUE;
+ /* HC4 match finder */
+ U32 matchIndex = ZSTD_insertAndFindFirstIndex (zc, ip, mls);
- /* Match Loop */
- while (ip < ilimit) {
- size_t matchLength=0;
- size_t offset=0;
- const BYTE* start=ip+1;
- U32 current = (U32)(start-base);
+ for ( ; (matchIndex>lowLimit) && (nbAttempts) ; nbAttempts--) {
+ const BYTE* match;
+ size_t currentMl=0;
+ if ((!extDict) || matchIndex >= dictLimit) {
+ match = base + matchIndex;
+ if (match[ml] == ip[ml]) /* potentially better */
+ currentMl = ZSTD_count(ip, match, iLimit);
+ } else {
+ match = dictBase + matchIndex;
+ if (MEM_read32(match) == MEM_read32(ip)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */
+ currentMl = ZSTD_count_2segments(ip+EQUAL_READ32, match+EQUAL_READ32, iLimit, dictEnd, prefixStart) + EQUAL_READ32;
+ }
- /* check repCode */
- {
- const U32 repIndex = (U32)(current - rep[0]);
- const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
- const BYTE* const repMatch = repBase + repIndex;
- if ((U32)((dictLimit-1) - repIndex) >= 3) /* intentional overflow */
- if (MEM_read32(start) == MEM_read32(repMatch)) {
- /* repcode detected we should take it */
- const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
- matchLength = ZSTD_count_2segments(start+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
- goto _storeSequence;
- } }
+ /* save best solution */
+ if (currentMl > ml) { ml = currentMl; *offsetPtr = ZSTD_REP_MOVE + current - matchIndex; if (ip+currentMl == iLimit) break; /* best possible, and avoid read overflow*/ }
- /* first search (depth 0) */
- { size_t offsetFound = 99999999;
- size_t const ml2 = ZSTD_HcFindBestMatch_extDict_selectMLS(ctx, ip, iend, &offsetFound, maxSearches, mls);
- if (ml2 > matchLength)
- matchLength = ml2, start = ip, offset=offsetFound;
- }
+ if (matchIndex <= minChain) break;
+ matchIndex = NEXT_IN_CHAIN(matchIndex, chainMask);
+ }
- if (matchLength < EQUAL_READ32) {
- ip += ((ip-anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
- continue;
- }
+ return ml;
+}
- /* catch up */
- if (offset >= ZSTD_REP_NUM) {
- U32 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++; }
- rep[1] = rep[0]; rep[0] = (U32)(offset - ZSTD_REP_MOVE);
- }
-_storeSequence:
- /* store sequence */
- { size_t const litLength = start - anchor;
- ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, matchLength-MINMATCH);
- anchor = ip = start + matchLength;
- }
+FORCE_INLINE size_t ZSTD_HcFindBestMatch_selectMLS (
+ ZSTD_CCtx* zc,
+ const BYTE* ip, const BYTE* const iLimit,
+ size_t* offsetPtr,
+ const U32 maxNbAttempts, const U32 matchLengthSearch)
+{
+ switch(matchLengthSearch)
+ {
+ default :
+ case 4 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 0);
+ case 5 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 0);
+ case 6 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 0);
+ }
+}
- /* check immediate repcode */
- while (ip <= ilimit) {
- const U32 repIndex = (U32)((ip-base) - rep[1]);
- const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
- const BYTE* const repMatch = repBase + repIndex;
- if ((U32)((dictLimit-1) - repIndex) >= 3) /* 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+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
- offset = rep[1]; rep[1] = rep[0]; rep[0] = (U32)offset; /* swap offset history */
- ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength-MINMATCH);
- ip += matchLength;
- anchor = ip;
- continue; /* faster when present ... (?) */
- }
- break;
- } }
- /* Last Literals */
- { size_t const lastLLSize = iend - anchor;
- memcpy(seqStorePtr->lit, anchor, lastLLSize);
- seqStorePtr->lit += lastLLSize;
+FORCE_INLINE size_t ZSTD_HcFindBestMatch_extDict_selectMLS (
+ ZSTD_CCtx* zc,
+ const BYTE* ip, const BYTE* const iLimit,
+ size_t* offsetPtr,
+ const U32 maxNbAttempts, const U32 matchLengthSearch)
+{
+ switch(matchLengthSearch)
+ {
+ default :
+ case 4 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 1);
+ case 5 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 1);
+ case 6 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 1);
}
}
+/* The optimal parser */
+#include "zstd_opt.h"
/* *******************************
const U32 maxSearches = 1 << ctx->params.cParams.searchLog;
const U32 mls = ctx->params.cParams.searchLength;
- const U32 minMatch = (mls == 3) ? 3 : 4;
typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
size_t* offsetPtr,
while (ip < ilimit) {
size_t matchLength=0;
size_t offset=0;
- const BYTE* start=ip;
+ const BYTE* start=ip+1;
/* check repCode */
- for (U32 i=0; i<ZSTD_REP_NUM; i++)
- if (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(ip - rep[i], minMatch)) {
+ if (MEM_read32(ip+1) == MEM_read32(ip+1 - rep[0])) {
/* repcode : we take it */
- if (matchLength==0) {
- matchLength = ZSTD_count(ip+minMatch, ip+minMatch-rep[i], iend) + minMatch;
- offset = i;
- } else {
- size_t mlRep = ZSTD_count(ip+minMatch, ip+minMatch-rep[i], iend) + minMatch;
- int gain2 = (int)(mlRep * 3 /*- ZSTD_highbit((U32)i+1)*/ + (i==1));
- int gain1 = (int)(matchLength*3 - /*ZSTD_highbit((U32)offset+1)*/ + 1 + (offset==1));
- if (gain2 > gain1)
- matchLength = mlRep, offset = i;
- }
+ matchLength = ZSTD_count(ip+1+EQUAL_READ32, ip+1+EQUAL_READ32-rep[0], iend) + EQUAL_READ32;
+ if (depth==0) goto _storeSequence;
}
/* first search (depth 0) */
matchLength = ml2, start = ip, offset=offsetFound;
}
- if (matchLength < MINMATCH) {
+ if (matchLength < EQUAL_READ32) {
ip += ((ip-anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
continue;
}
if (depth>=1)
while (ip<ilimit) {
ip ++;
- for (U32 i=0; i<ZSTD_REP_NUM; i++)
- if (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(ip - rep[i], minMatch)) {
- size_t const mlRep = ZSTD_count(ip+minMatch, ip+minMatch-rep[i], iend) + minMatch;
+ if ((offset) && (MEM_read32(ip) == MEM_read32(ip - rep[0]))) {
+ size_t const mlRep = ZSTD_count(ip+EQUAL_READ32, ip+EQUAL_READ32-rep[0], iend) + EQUAL_READ32;
int const gain2 = (int)(mlRep * 3);
- int const gain1 = (int)(matchLength*3 - ZSTD_highbit((U32)offset+1) + 1 + (offset<ZSTD_REP_NUM));
- if ((mlRep >= MINMATCH) && (gain2 > gain1))
- matchLength = mlRep, offset = i, start = ip;
+ int const gain1 = (int)(matchLength*3 - ZSTD_highbit((U32)offset+1) + 1);
+ if ((mlRep >= EQUAL_READ32) && (gain2 > gain1))
+ matchLength = mlRep, offset = 0, start = ip;
}
{ size_t offset2=99999999;
size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int const gain2 = (int)(ml2*4 - ZSTD_highbit((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 4);
- if ((ml2 >= MINMATCH) && (gain2 > gain1)) {
+ if ((ml2 >= EQUAL_READ32) && (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 ++;
- for (U32 i=0; i<ZSTD_REP_NUM; i++)
- if (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(ip - rep[i], minMatch)) {
- size_t const ml2 = ZSTD_count(ip+minMatch, ip+minMatch-rep[i], iend) + minMatch;
+ if ((offset) && (MEM_read32(ip) == MEM_read32(ip - rep[0]))) {
+ size_t const ml2 = ZSTD_count(ip+EQUAL_READ32, ip+EQUAL_READ32-rep[0], iend) + EQUAL_READ32;
int const gain2 = (int)(ml2 * 4);
- int const gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 1 + (offset<ZSTD_REP_NUM));
- if ((ml2 >= MINMATCH) && (gain2 > gain1))
- matchLength = ml2, offset = i, start = ip;
+ int const gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 1);
+ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1))
+ matchLength = ml2, offset = 0, start = ip;
}
{ size_t offset2=99999999;
size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int const gain2 = (int)(ml2*4 - ZSTD_highbit((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 7);
- if ((ml2 >= MINMATCH) && (gain2 > gain1)) {
+ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
continue;
} } }
}
/* catch up */
- if (offset >= ZSTD_REP_NUM) {
+ if (offset) {
while ((start>anchor) && (start>base+offset-ZSTD_REP_MOVE) && (start[-1] == start[-1-offset+ZSTD_REP_MOVE])) /* only search for offset within prefix */
{ start--; matchLength++; }
+ rep[1] = rep[0]; rep[0] = (U32)(offset - ZSTD_REP_MOVE);
}
/* store sequence */
- {
- if (offset >= ZSTD_REP_NUM) {
- rep[2] = rep[1];
- rep[1] = rep[0];
- rep[0] = (U32)(offset - ZSTD_REP_MOVE);
- } else {
- if (offset != 0) {
- U32 temp = rep[offset];
- if (offset > 1) rep[2] = rep[1];
- if (offset > 0) rep[1] = rep[0];
- rep[0] = temp;
- }
-
- if (offset<=1 && start==anchor) offset = 1-offset;
- }
-
- size_t const litLength = start - anchor;
-
+_storeSequence:
+ { size_t const litLength = start - anchor;
ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, matchLength-MINMATCH);
anchor = ip = start + matchLength;
}
- }
+
+ /* check immediate repcode */
+ while ( (ip <= ilimit)
+ && (MEM_read32(ip) == MEM_read32(ip - rep[1])) ) {
+ /* store sequence */
+ matchLength = ZSTD_count(ip+EQUAL_READ32, ip+EQUAL_READ32-rep[1], iend) + EQUAL_READ32;
+ offset = rep[1]; rep[1] = rep[0]; rep[0] = (U32)offset; /* swap repcodes */
+ ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength-MINMATCH);
+ ip += matchLength;
+ anchor = ip;
+ continue; /* faster when present ... (?) */
+ } }
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;
}
-/* The optimal parser */
-#include "zstd_opt.h"
-
static void ZSTD_compressBlock_btopt(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
static void ZSTD_compressBlock_greedy(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
- ZSTD_compressBlock_greedy_generic(ctx, src, srcSize);
+ ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 0);
}
const U32 maxSearches = 1 << ctx->params.cParams.searchLog;
const U32 mls = ctx->params.cParams.searchLength;
- const U32 minMatch = (mls == 3) ? 3 : 4;
typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
size_t* offsetPtr,
while (ip < ilimit) {
size_t matchLength=0;
size_t offset=0;
- const BYTE* start=ip;
+ const BYTE* start=ip+1;
U32 current = (U32)(ip-base);
/* check repCode */
- for (U32 i=0; i<ZSTD_REP_NUM; i++) {
- const U32 repIndex = (U32)(current - rep[i]);
+ {
+ const U32 repIndex = (U32)(current+1 - rep[0]);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ((U32)((dictLimit-1) - repIndex) >= 3) /* intentional overflow */
- if (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) {
+ if (MEM_read32(ip+1) == MEM_read32(repMatch)) {
/* repcode detected we should take it */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
- if (matchLength==0) {
- offset = i;
- matchLength = ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
- } else {
- size_t mlRep = ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
- int gain2 = (int)(mlRep * 3 /*- ZSTD_highbit((U32)i+1)*/ + (i==1));
- int gain1 = (int)(matchLength*3 - /*ZSTD_highbit((U32)offset+1)*/ + 1 + (offset==1));
- if (gain2 > gain1)
- matchLength = mlRep, offset = i;
- }
+ matchLength = ZSTD_count_2segments(ip+1+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
+ if (depth==0) goto _storeSequence;
} }
/* first search (depth 0) */
matchLength = ml2, start = ip, offset=offsetFound;
}
- if (matchLength < MINMATCH) {
+ if (matchLength < EQUAL_READ32) {
ip += ((ip-anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
continue;
}
ip ++;
current++;
/* check repCode */
- for (U32 i=0; i<ZSTD_REP_NUM; i++) {
- const U32 repIndex = (U32)(current - rep[i]);
+ if (offset) {
+ const U32 repIndex = (U32)(current - rep[0]);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ((U32)((dictLimit-1) - repIndex) >= 3) /* intentional overflow */
- if (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) {
+ 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+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
+ size_t const repLength = ZSTD_count_2segments(ip+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
int const gain2 = (int)(repLength * 3);
- int const gain1 = (int)(matchLength*3 - ZSTD_highbit((U32)offset+1) + 1 + (offset<ZSTD_REP_NUM));
- if ((repLength >= MINMATCH) && (gain2 > gain1))
- matchLength = repLength, offset = i, start = ip;
+ int const gain1 = (int)(matchLength*3 - ZSTD_highbit((U32)offset+1) + 1);
+ if ((repLength >= EQUAL_READ32) && (gain2 > gain1))
+ matchLength = repLength, offset = 0, start = ip;
} }
/* search match, depth 1 */
size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int const gain2 = (int)(ml2*4 - ZSTD_highbit((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 4);
- if ((ml2 >= MINMATCH) && (gain2 > gain1)) {
+ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
continue; /* search a better one */
} }
ip ++;
current++;
/* check repCode */
- for (U32 i=0; i<ZSTD_REP_NUM; i++) {
- const U32 repIndex = (U32)(current - rep[i]);
+ if (offset) {
+ const U32 repIndex = (U32)(current - rep[0]);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ((U32)((dictLimit-1) - repIndex) >= 3) /* intentional overflow */
- if (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) {
+ 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+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
- int const gain2 = (int)(repLength * 4);
- int const gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 1 + (offset<ZSTD_REP_NUM));
- if ((repLength >= MINMATCH) && (gain2 > gain1))
- matchLength = repLength, offset = i, start = ip;
+ size_t repLength = ZSTD_count_2segments(ip+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
+ int gain2 = (int)(repLength * 4);
+ int gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 1);
+ if ((repLength >= EQUAL_READ32) && (gain2 > gain1))
+ matchLength = repLength, offset = 0, start = ip;
} }
/* search match, depth 2 */
size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int const gain2 = (int)(ml2*4 - ZSTD_highbit((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 7);
- if ((ml2 >= MINMATCH) && (gain2 > gain1)) {
+ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
continue;
} } }
}
/* catch up */
- if (offset >= ZSTD_REP_NUM) {
+ if (offset) {
U32 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 */
+ rep[1] = rep[0]; rep[0] = (U32)(offset - ZSTD_REP_MOVE);
}
/* store sequence */
- {
- if (offset >= ZSTD_REP_NUM) {
- rep[2] = rep[1];
- rep[1] = rep[0];
- rep[0] = (U32)(offset - ZSTD_REP_MOVE);
- } else {
- if (offset != 0) {
- U32 temp = rep[offset];
- if (offset > 1) rep[2] = rep[1];
- if (offset > 0) rep[1] = rep[0];
- rep[0] = temp;
- }
-
- if (offset<=1 && start==anchor) offset = 1-offset;
- }
-
- size_t const litLength = start - anchor;
+_storeSequence:
+ { size_t const litLength = start - anchor;
ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, matchLength-MINMATCH);
anchor = ip = start + matchLength;
+ }
+
+ /* check immediate repcode */
+ while (ip <= ilimit) {
+ const U32 repIndex = (U32)((ip-base) - rep[1]);
+ const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
+ const BYTE* const repMatch = repBase + repIndex;
+ if ((U32)((dictLimit-1) - repIndex) >= 3) /* 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+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
+ offset = rep[1]; rep[1] = rep[0]; rep[0] = (U32)offset; /* swap offset history */
+ ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength-MINMATCH);
+ ip += matchLength;
+ anchor = ip;
+ continue; /* faster when present ... (?) */
+ }
+ break;
} }
/* Last Literals */
}
}
+
void ZSTD_compressBlock_greedy_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
- ZSTD_compressBlock_greedy_extDict_generic(ctx, src, srcSize);
+ ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 0);
}
static void ZSTD_compressBlock_lazy_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
static ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int extDict)
{
static const ZSTD_blockCompressor blockCompressor[2][6] = {
-#if 1
+#if 0
{ ZSTD_compressBlock_fast, ZSTD_compressBlock_greedy, ZSTD_compressBlock_lazy, ZSTD_compressBlock_lazy2, ZSTD_compressBlock_btlazy2, ZSTD_compressBlock_btopt },
#else
{ ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_greedy_extDict, ZSTD_compressBlock_lazy_extDict,ZSTD_compressBlock_lazy2_extDict, ZSTD_compressBlock_btlazy2_extDict, ZSTD_compressBlock_btopt_extDict },
{ 14, 14, 14, 1, 4, 4, ZSTD_fast }, /* level 1 */
{ 14, 14, 15, 1, 4, 4, ZSTD_fast }, /* level 2 */
{ 14, 14, 14, 4, 4, 4, ZSTD_greedy }, /* level 3.*/
-#if 0
- { 14, 14, 14, 3, 3, 4, ZSTD_lazy }, /* level 4.*/
- { 14, 14, 14, 4, 3, 4, ZSTD_lazy2 }, /* level 5 */
- { 14, 14, 14, 5, 3, 4, ZSTD_lazy2 }, /* level 6 */
- { 14, 14, 14, 6, 3, 4, ZSTD_lazy2 }, /* level 7.*/
- { 14, 14, 14, 7, 3, 4, ZSTD_lazy2 }, /* level 8.*/
- { 14, 15, 14, 6, 3, 4, ZSTD_btlazy2 }, /* level 9.*/
-#else
{ 14, 14, 14, 3, 4, 4, ZSTD_lazy }, /* level 4.*/
{ 14, 14, 14, 4, 4, 4, ZSTD_lazy2 }, /* level 5 */
{ 14, 14, 14, 5, 4, 4, ZSTD_lazy2 }, /* level 6 */
{ 14, 14, 14, 6, 4, 4, ZSTD_lazy2 }, /* level 7.*/
{ 14, 14, 14, 7, 4, 4, ZSTD_lazy2 }, /* level 8.*/
{ 14, 15, 14, 6, 4, 4, ZSTD_btlazy2 }, /* level 9.*/
-#endif
{ 14, 15, 14, 3, 3, 6, ZSTD_btopt }, /* level 10.*/
{ 14, 15, 14, 6, 3, 8, ZSTD_btopt }, /* level 11.*/
{ 14, 15, 14, 6, 3, 16, ZSTD_btopt }, /* level 12.*/
projects / thirdparty / zstd.git / commitdiff
