AuroraMiddleware/zstd
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
55a444764b
zstd/lib/zstd_opt.c
inikep 55a444764b sufficient_len = 32
2016-02-04 22:22:47 +01:00

976 lines
38 KiB
C
Raw Blame History

#include <stdio.h>
#include <math.h> // log
typedef struct
{
int off;
int len;
int back;
} ZSTD_match_t;
typedef struct
{
int price;
int off;
int mlen;
int litlen;
int rep;
int rep2;
} ZSTD_optimal_t;
#if 1
#define ZSTD_LOG_PARSER(fmt, args...) ;// printf(fmt, ##args)
#define ZSTD_LOG_PRICE(fmt, args...) ;//printf(fmt, ##args)
#define ZSTD_LOG_ENCODE(fmt, args...) ;//printf(fmt, ##args)
#else
#define ZSTD_LOG_PARSER(fmt, args...) printf(fmt, ##args)
#define ZSTD_LOG_PRICE(fmt, args...) printf(fmt, ##args)
#define ZSTD_LOG_ENCODE(fmt, args...) printf(fmt, ##args)
#endif
#define ZSTD_LOG_TRY_PRICE(fmt, args...) ;//printf(fmt, ##args)
#define ZSTD_OPT_NUM (1<<12)
#define ZSTD_FREQ_THRESHOLD (256)
const int tab32[32] = {
0, 9, 1, 10, 13, 21, 2, 29,
11, 14, 16, 18, 22, 25, 3, 30,
8, 12, 20, 28, 15, 17, 24, 7,
19, 27, 23, 6, 26, 5, 4, 31};
int log2_32 (uint32_t value)
{
value |= value >> 1;
value |= value >> 2;
value |= value >> 4;
value |= value >> 8;
value |= value >> 16;
return tab32[(uint32_t)(value*0x07C4ACDD) >> 27];
}
FORCE_INLINE size_t ZSTD_getLiteralPriceReal(seqStore_t* seqStorePtr, size_t litLength, const BYTE* literals)
{
size_t price = 0;
if (litLength > 0) {
/* literals */
for (int i=litLength-1; i>=0; i--)
price += log2_32(seqStorePtr->litSum) - log2_32(seqStorePtr->litFreq[literals[i]]);
/* literal Length */
size_t freq;
if (litLength >= MaxLL) {
freq = seqStorePtr->litLengthFreq[MaxLL];
if (litLength<255 + MaxLL) {
price += 8;
} else {
price += 8;
if (litLength < (1<<15)) price += 16; else price += 24;
} }
else
freq = seqStorePtr->litLengthFreq[litLength];
price += log2_32(seqStorePtr->litLengthSum) - log2_32(freq);
}
return price + (price == 0);
}
FORCE_INLINE size_t ZSTD_getLiteralPrice(seqStore_t* seqStorePtr, size_t litLength, const BYTE* literals)
{
if (seqStorePtr->litSum > ZSTD_FREQ_THRESHOLD)
return ZSTD_getLiteralPriceReal(seqStorePtr, litLength, literals);
return 1 + (litLength<<3);
}
FORCE_INLINE size_t ZSTD_getMatchPriceReal(seqStore_t* seqStorePtr, size_t offset, size_t matchLength)
{
/* match offset */
BYTE offCode = (BYTE)ZSTD_highbit(offset) + 1;
if (offset==0)
offCode = 0;
size_t price = log2_32(seqStorePtr->offCodeSum) - log2_32(seqStorePtr->offCodeFreq[offCode]);
price += offCode;
/* match Length */
size_t freq;
if (matchLength >= MaxML) {
freq = seqStorePtr->matchLengthFreq[MaxML];
if (matchLength < 255+MaxML) {
price += 8;
} else {
price += 8;
if (matchLength < (1<<15)) price += 16; else price += 24;
} }
else freq = seqStorePtr->matchLengthFreq[matchLength];
price += log2_32(seqStorePtr->matchLengthSum) - log2_32(freq);
return price;
}
FORCE_INLINE size_t ZSTD_getPrice(seqStore_t* seqStorePtr, size_t litLength, const BYTE* literals, size_t offset, size_t matchLength)
{
if (seqStorePtr->litSum > ZSTD_FREQ_THRESHOLD)
return ZSTD_getLiteralPriceReal(seqStorePtr, litLength, literals) + ZSTD_getMatchPriceReal(seqStorePtr, offset, matchLength);
return (litLength<<3) + ZSTD_highbit((U32)matchLength+1) + Offbits + ZSTD_highbit((U32)offset+1);
}
MEM_STATIC void ZSTD_updatePrice(seqStore_t* seqStorePtr, size_t litLength, const BYTE* literals, size_t offset, size_t matchLength)
{
#if 0
static const BYTE* g_start = NULL;
if (g_start==NULL) g_start = literals;
//if (literals - g_start == 8695)
printf("pos %6u : %3u literals & match %3u bytes at distance %6u \n",
(U32)(literals - g_start), (U32)litLength, (U32)matchLength+4, (U32)offset);
#endif
/* literals */
seqStorePtr->litSum += litLength;
for (int i=litLength-1; i>=0; i--)
seqStorePtr->litFreq[literals[i]]++;
/* literal Length */
seqStorePtr->litLengthSum++;
if (litLength >= MaxLL)
seqStorePtr->litLengthFreq[MaxLL]++;
else
seqStorePtr->litLengthFreq[litLength]++;
/* match offset */
seqStorePtr->offCodeSum++;
BYTE offCode = (BYTE)ZSTD_highbit(offset) + 1;
if (offset==0) offCode=0;
seqStorePtr->offCodeFreq[offCode]++;
/* match Length */
seqStorePtr->matchLengthSum++;
if (matchLength >= MaxML)
seqStorePtr->matchLengthFreq[MaxML]++;
else
seqStorePtr->matchLengthFreq[matchLength]++;
}
#define SET_PRICE(pos, mlen_, offset_, litlen_, price_) \
{ \
while (last_pos < pos) { opt[last_pos+1].price = 1<<30; last_pos++; } \
opt[pos].mlen = mlen_; \
opt[pos].off = offset_; \
opt[pos].litlen = litlen_; \
opt[pos].price = price_; \
ZSTD_LOG_PARSER("%d: SET price[%d/%d]=%d litlen=%d len=%d off=%d\n", (int)(inr-base), (int)pos, (int)last_pos, opt[pos].price, opt[pos].litlen, opt[pos].mlen, opt[pos].off); \
}
FORCE_INLINE /* inlining is important to hardwire a hot branch (template emulation) */
size_t ZSTD_insertBtAndGetAllMatches (
ZSTD_CCtx* zc,
const BYTE* const ip, const BYTE* const iend,
U32 nbCompares, const U32 mls,
U32 extDict, ZSTD_match_t* matches, size_t bestLength)
{
U32* const hashTable = zc->hashTable;
const U32 hashLog = zc->params.hashLog;
const size_t h = ZSTD_hashPtr(ip, hashLog, mls);
U32* const bt = zc->contentTable;
const U32 btLog = zc->params.contentLog - 1;
const U32 btMask= (1 << btLog) - 1;
U32 matchIndex = hashTable[h];
size_t commonLengthSmaller=0, commonLengthLarger=0;
const BYTE* const base = zc->base;
const BYTE* const dictBase = zc->dictBase;
const U32 dictLimit = zc->dictLimit;
const BYTE* const dictEnd = dictBase + dictLimit;
const BYTE* const prefixStart = base + dictLimit;
const U32 current = (U32)(ip-base);
const U32 btLow = btMask >= current ? 0 : current - btMask;
const U32 windowLow = zc->lowLimit;
U32* smallerPtr = bt + 2*(current&btMask);
U32* largerPtr = bt + 2*(current&btMask) + 1;
U32 matchEndIdx = current+8;
U32 dummy32; /* to be nullified at the end */
size_t mnum = 0;
bestLength = 0;
hashTable[h] = current; /* Update Hash Table */
while (nbCompares-- && (matchIndex > windowLow)) {
U32* nextPtr = bt + 2*(matchIndex & btMask);
size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
const BYTE* match;
if ((!extDict) || (matchIndex+matchLength >= dictLimit)) {
match = base + matchIndex;
if (match[matchLength] == ip[matchLength])
matchLength += ZSTD_count(ip+matchLength+1, match+matchLength+1, iend) +1;
} 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 (matchLength >= MINMATCH) {
bestLength = matchLength;
matches[mnum].off = current - matchIndex;
matches[mnum].len = matchLength;
matches[mnum].back = 0;
mnum++;
}
if (matchLength > ZSTD_OPT_NUM) break;
}
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;
zc->nextToUpdate = (matchEndIdx > current + 8) ? matchEndIdx - 8 : current+1;
return mnum;
}
/** Tree updater, providing best match */
FORCE_INLINE /* inlining is important to hardwire a hot branch (template emulation) */
size_t ZSTD_BtGetAllMatches (
ZSTD_CCtx* zc,
const BYTE* const ip, const BYTE* const iLimit,
const U32 maxNbAttempts, const U32 mls, ZSTD_match_t* matches, size_t minml)
{
if (ip < zc->base + zc->nextToUpdate) return 0; /* skipped area */
ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls);
return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 0, matches, minml);
}
FORCE_INLINE size_t ZSTD_BtGetAllMatches_selectMLS (
ZSTD_CCtx* zc, /* Index table will be updated */
const BYTE* ip, const BYTE* const iLowLimit, const BYTE* const iHighLimit,
const U32 maxNbAttempts, const U32 matchLengthSearch, ZSTD_match_t* matches, size_t minml)
{
switch(matchLengthSearch)
{
default :
case 4 : return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minml);
case 5 : return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minml);
case 6 : return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minml);
}
}
FORCE_INLINE /* inlining is important to hardwire a hot branch (template emulation) */
size_t ZSTD_HcGetAllMatches_generic (
ZSTD_CCtx* zc, /* Index table will be updated */
const BYTE* const ip, const BYTE* const iLowLimit, const BYTE* const iHighLimit,
const U32 maxNbAttempts, const U32 mls, const U32 extDict, ZSTD_match_t* matches, size_t minml)
{
U32* const chainTable = zc->contentTable;
const U32 chainSize = (1 << zc->params.contentLog);
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;
U32 matchIndex;
const BYTE* match;
int nbAttempts=maxNbAttempts;
size_t mnum = 0;
minml=MINMATCH-1;
/* HC4 match finder */
matchIndex = ZSTD_insertAndFindFirstIndex (zc, ip, mls);
while ((matchIndex>lowLimit) && (nbAttempts)) {
size_t currentMl=0;
size_t back = 0;
nbAttempts--;
if ((!extDict) || matchIndex >= dictLimit) {
match = base + matchIndex;
if (match[minml] == ip[minml]) /* potentially better */
currentMl = ZSTD_count(ip, match, iHighLimit);
#if 0
const BYTE* start = ip;
size_t offset = current - matchIndex;
while ((start > iLowLimit) && (start > base+offset) && (start[-1] == start[-1-offset])) start--;
back = ip - start;
#else
// while ((match-back > base) && (ip-back > iLowLimit) && (ip[-back-1] == match[-back-1])) back++;
#endif
currentMl += back;
} else {
match = dictBase + matchIndex;
if (MEM_read32(match) == MEM_read32(ip)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */
currentMl = ZSTD_count_2segments(ip+MINMATCH, match+MINMATCH, iHighLimit, dictEnd, prefixStart) + MINMATCH;
}
/* save best solution */
if (currentMl > minml) {
minml = currentMl;
matches[mnum].off = current - matchIndex;
matches[mnum].len = currentMl;
matches[mnum].back = back;
mnum++;
if (currentMl > ZSTD_OPT_NUM) break;
if (ip+currentMl == iHighLimit) break; /* best possible, and avoid read overflow*/
}
if (matchIndex <= minChain) break;
matchIndex = NEXT_IN_CHAIN(matchIndex, chainMask);
}
return mnum;
}
FORCE_INLINE size_t ZSTD_HcGetAllMatches_selectMLS (
ZSTD_CCtx* zc,
const BYTE* ip, const BYTE* const iLowLimit, const BYTE* const iHighLimit,
const U32 maxNbAttempts, const U32 matchLengthSearch, ZSTD_match_t* matches, size_t minml)
{
switch(matchLengthSearch)
{
default :
case 4 : return ZSTD_HcGetAllMatches_generic(zc, ip, iLowLimit, iHighLimit, maxNbAttempts, 4, 0, matches, minml);
case 5 : return ZSTD_HcGetAllMatches_generic(zc, ip, iLowLimit, iHighLimit, maxNbAttempts, 5, 0, matches, minml);
case 6 : return ZSTD_HcGetAllMatches_generic(zc, ip, iLowLimit, iHighLimit, maxNbAttempts, 6, 0, matches, minml);
}
}
void print_hex_text(uint8_t* buf, int bufsize, int endline)
{
int i, j;
for (i=0; i<bufsize; i+=16)
{
printf("%02d:", i);
for (j=0; j<16; j++)
if (i+j<bufsize)
printf("%02x,",buf[i+j]);
else
printf(" ");
printf(" ");
for (j=0; i+j<bufsize && j<16; j++)
printf("%c",buf[i+j]>32?buf[i+j]:'.');
printf("\n");
}
if (endline) printf("\n");
}
/* *******************************
* Old parser
*********************************/
FORCE_INLINE
void ZSTD_compressBlock_opt2_generic(ZSTD_CCtx* ctx,
const void* src, size_t srcSize,
const U32 searchMethod, const U32 depth)
{
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;
size_t offset_2=REPCODE_STARTVALUE, offset_1=REPCODE_STARTVALUE;
const U32 maxSearches = 1 << ctx->params.searchLog;
const U32 mls = ctx->params.searchLength;
typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
size_t* offsetPtr,
U32 maxNbAttempts, U32 matchLengthSearch);
searchMax_f searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS;
#if 0
typedef size_t (*getAllMatches_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
U32 maxNbAttempts, U32 matchLengthSearch, ZSTD_match_t* matches);
getAllMatches_f getAllMatches = searchMethod ? ZSTD_BtGetAllMatches_selectMLS : ZSTD_HcGetAllMatches_selectMLS;
ZSTD_match_t matches[ZSTD_OPT_NUM+1];
#endif
/* init */
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;
#define ZSTD_USE_REP
#ifdef ZSTD_USE_REP
/* check repCode */
if (MEM_read32(start) == MEM_read32(start - offset_1)) {
/* repcode : we take it */
matchLength = ZSTD_count(start+MINMATCH, start+MINMATCH-offset_1, iend) + MINMATCH;
if (depth==0) goto _storeSequence;
}
#endif
{
/* first search (depth 0) */
#if 1
size_t offsetFound = 99999999;
size_t ml2 = searchMax(ctx, ip, iend, &offsetFound, maxSearches, mls);
if (ml2 > matchLength)
start=ip, matchLength = ml2, offset=offsetFound;
#else
size_t mnum = getAllMatches(ctx, ip, iend, maxSearches, mls, matches);
if (mnum > 0) {
if (matches[mnum-1].len > matchLength)
start=ip, matchLength = matches[mnum-1].len, offset=matches[mnum-1].off;
}
#endif
}
if (matchLength < MINMATCH) {
// ip += ((ip-anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
ip++;
continue;
}
#if 1
/* let's try to find a better solution */
if (depth>=1)
while (ip<ilimit) {
ip ++;
#ifdef ZSTD_USE_REP
if ((offset) && (MEM_read32(ip) == MEM_read32(ip - offset_1))) {
size_t mlRep = ZSTD_count(ip+MINMATCH, ip+MINMATCH-offset_1, iend) + MINMATCH;
int gain2 = (int)(mlRep * 3);
int gain1 = (int)(matchLength*3 - ZSTD_highbit((U32)offset+1) + 1);
if ((mlRep >= MINMATCH) && (gain2 > gain1))
matchLength = mlRep, offset = 0, start = ip;
}
#endif
{
size_t offset2=999999;
size_t ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int gain2 = (int)(ml2*4 - ZSTD_highbit((U32)offset2+1)); /* raw approx */
int gain1 = (int)(matchLength*4 - ZSTD_highbit((U32)offset+1) + 4);
if ((ml2 >= MINMATCH) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
continue; /* search a better one */
} }
break; /* nothing found : store previous solution */
}
#endif
/* store sequence */
_storeSequence:
/* catch up */
if (offset) {
while ((start>anchor) && (start>base+offset) && (start[-1] == start[-1-offset])) /* only search for offset within prefix */
{ start--; matchLength++; }
offset_2 = offset_1; offset_1 = offset;
}
{
size_t litLength = start - anchor;
ZSTD_LOG_ENCODE("%d/%d: ENCODE literals=%d off=%d mlen=%d offset_1=%d offset_2=%d\n", (int)(ip-base), (int)(iend-base), (int)(litLength), (int)(offset), (int)matchLength, (int)offset_1, (int)offset_2);
ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, matchLength-MINMATCH);
anchor = ip = start + matchLength;
}
#ifdef ZSTD_USE_REP /* check immediate repcode */
while ( (ip <= ilimit)
&& (MEM_read32(ip) == MEM_read32(ip - offset_2)) ) {
/* store sequence */
matchLength = ZSTD_count(ip+MINMATCH, ip+MINMATCH-offset_2, iend);
offset = offset_2;
offset_2 = offset_1;
offset_1 = offset;
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength);
ip += matchLength+MINMATCH;
anchor = ip;
continue; /* faster when present ... (?) */
}
#endif
}
/* Last Literals */
{
size_t lastLLSize = iend - anchor;
ZSTD_LOG_ENCODE("%d/%d: ENCODE lastLLSize=%d\n", (int)(ip-base), (int)(iend-base), (int)(lastLLSize));
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
/* *******************************
* Optimal parser
*********************************/
FORCE_INLINE
void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
const void* src, size_t srcSize,
const U32 searchMethod, const U32 depth)
{
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;
size_t rep_2=REPCODE_STARTVALUE, rep_1=REPCODE_STARTVALUE;
const U32 maxSearches = 1 << ctx->params.searchLog;
const U32 mls = ctx->params.searchLength;
typedef size_t (*getAllMatches_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLowLimit, const BYTE* iHighLimit,
U32 maxNbAttempts, U32 matchLengthSearch, ZSTD_match_t* matches, size_t minml);
getAllMatches_f getAllMatches = searchMethod ? ZSTD_BtGetAllMatches_selectMLS : ZSTD_HcGetAllMatches_selectMLS;
ZSTD_optimal_t opt[ZSTD_OPT_NUM+4];
ZSTD_match_t matches[ZSTD_OPT_NUM+1];
const uint8_t *inr;
ssize_t skip_num = 0, cur, cur2, last_pos, litlen, price, match_num;
const ssize_t sufficient_len = 32; //ctx->params.sufficientLength;
const size_t faster_get_matches = (ctx->params.strategy == ZSTD_opt);
// printf("orig_file="); print_hex_text(ip, srcSize, 0);
/* init */
ZSTD_resetSeqStore(seqStorePtr);
if ((ip-base) < REPCODE_STARTVALUE) ip = base + REPCODE_STARTVALUE;
/* Match Loop */
while (ip < ilimit) {
ssize_t mlen=0;
ssize_t best_mlen=0;
ssize_t best_off=0;
memset(opt, 0, sizeof(ZSTD_optimal_t));
last_pos = 0;
inr = ip;
opt[0].litlen = ip - anchor;
/* check repCode */
if (MEM_read32(ip+1) == MEM_read32(ip+1 - rep_1)) {
/* repcode : we take it */
mlen = ZSTD_count(ip+1+MINMATCH, ip+1+MINMATCH-rep_1, iend) + MINMATCH;
ZSTD_LOG_PARSER("%d: start try REP rep=%d mlen=%d\n", (int)(ip-base), (int)rep_1, (int)mlen);
if (depth==0 || mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
ip+=1; best_mlen = mlen; best_off = 0; cur = 0; last_pos = 1;
goto _storeSequence;
}
litlen = opt[0].litlen + 1;
do
{
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, 0, mlen - MINMATCH);
if (mlen + 1 > last_pos || price < opt[mlen + 1].price)
SET_PRICE(mlen + 1, mlen, 0, litlen, price);
mlen--;
}
while (mlen >= MINMATCH);
}
best_mlen = (last_pos) ? last_pos : MINMATCH;
if (faster_get_matches && last_pos)
match_num = 0;
else
match_num = getAllMatches(ctx, ip, ip, iend, maxSearches, mls, matches, best_mlen); /* first search (depth 0) */
ZSTD_LOG_PARSER("%d: match_num=%d last_pos=%d\n", (int)(ip-base), match_num, last_pos);
if (!last_pos && !match_num) { ip++; continue; }
opt[0].rep = rep_1;
opt[0].rep2 = rep_2;
opt[0].mlen = 1;
if (match_num && matches[match_num-1].len > sufficient_len)
{
best_mlen = matches[match_num-1].len;
best_off = matches[match_num-1].off;
cur = 0;
last_pos = 1;
goto _storeSequence;
}
// set prices using matches at position = 0
for (int i = 0; i < match_num; i++)
{
mlen = (i>0) ? matches[i-1].len+1 : best_mlen;
best_mlen = (matches[i].len < ZSTD_OPT_NUM) ? matches[i].len : ZSTD_OPT_NUM;
ZSTD_LOG_PARSER("%d: start Found mlen=%d off=%d best_mlen=%d last_pos=%d\n", (int)(ip-base), matches[i].len, matches[i].off, (int)best_mlen, (int)last_pos);
litlen = opt[0].litlen;
while (mlen <= best_mlen)
{
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[i].off, mlen - MINMATCH);
if (mlen > last_pos || price < opt[mlen].price)
SET_PRICE(mlen, mlen, matches[i].off, litlen, price);
mlen++;
}
}
if (last_pos < MINMATCH) {
// ip += ((ip-anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
ip++; continue;
}
// check further positions
for (skip_num = 0, cur = 1; cur <= last_pos; cur++)
{
inr = ip + cur;
if (opt[cur-1].mlen == 1)
{
litlen = opt[cur-1].litlen + 1;
if (cur > litlen)
{
price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr-litlen);
ZSTD_LOG_TRY_PRICE("%d: TRY1 opt[%d].price=%d price=%d cur=%d litlen=%d\n", (int)(inr-base), cur - litlen, opt[cur - litlen].price, price, cur, litlen);
}
else
price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
}
else
{
litlen = 1;
price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr-1);
ZSTD_LOG_TRY_PRICE("%d: TRY3 price=%d cur=%d litlen=%d litonly=%d\n", (int)(inr-base), price, cur, litlen, (int)ZSTD_getLiteralPrice(seqStorePtr, litlen, inr-1));
}
ZSTD_LOG_TRY_PRICE("%d: TRY4 price=%d opt[%d].price=%d\n", (int)(inr-base), price, cur, opt[cur].price);
if (cur > last_pos || price <= opt[cur].price) // || ((price == opt[cur].price) && (opt[cur-1].mlen == 1) && (cur != litlen)))
SET_PRICE(cur, 1, 0, litlen, price);
if (cur == last_pos) break;
if (inr > ilimit) // last match must start at a minimum distance of 8 from oend
continue;
mlen = opt[cur].mlen;
if (opt[cur-mlen].off)
{
opt[cur].rep2 = opt[cur-mlen].rep;
opt[cur].rep = opt[cur-mlen].off;
ZSTD_LOG_PARSER("%d: COPYREP1 cur=%d mlen=%d rep=%d rep2=%d\n", (int)(inr-base), cur, mlen, opt[cur].rep, opt[cur].rep2);
}
else
{
if (cur!=mlen && opt[cur-mlen].litlen == 0)
{
opt[cur].rep2 = opt[cur-mlen].rep;
opt[cur].rep = opt[cur-mlen].rep2;
ZSTD_LOG_PARSER("%d: COPYREP2 cur=%d mlen=%d rep=%d rep2=%d\n", (int)(inr-base), cur, mlen, opt[cur].rep, opt[cur].rep2);
}
else
{
opt[cur].rep2 = opt[cur-mlen].rep2;
opt[cur].rep = opt[cur-mlen].rep;
ZSTD_LOG_PARSER("%d: COPYREP3 cur=%d mlen=%d rep=%d rep2=%d\n", (int)(inr-base), cur, mlen, opt[cur].rep, opt[cur].rep2);
}
}
ZSTD_LOG_PARSER("%d: CURRENT price[%d/%d]=%d off=%d mlen=%d litlen=%d rep=%d rep2=%d\n", (int)(inr-base), cur, last_pos, opt[cur].price, opt[cur].off, opt[cur].mlen, opt[cur].litlen, opt[cur].rep, opt[cur].rep2);
if (!opt[cur].off && opt[cur].mlen != 1) {
mlen = ZSTD_count(inr, inr - opt[cur].rep2, iend); // check rep2
ZSTD_LOG_PARSER("%d: try REP2 rep2=%d mlen=%d\n", (int)(inr-base), opt[cur].rep2, mlen);
}
else {
mlen = ZSTD_count(inr, inr - opt[cur].rep, iend); // check rep
ZSTD_LOG_PARSER("%d: try REP1 rep=%d mlen=%d\n", (int)(inr-base), opt[cur].rep, mlen);
}
best_mlen = 0;
if (mlen >= MINMATCH)
{
ZSTD_LOG_PARSER("%d: Found REP mlen=%d off=%d rep=%d opt[%d].off=%d\n", (int)(inr-base), mlen, 0, opt[cur].rep, cur, opt[cur].off);
if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM)
{
best_mlen = mlen;
best_off = 0;
ZSTD_LOG_PARSER("%d: REP sufficient_len=%d best_mlen=%d best_off=%d last_pos=%d\n", (int)(inr-base), sufficient_len, best_mlen, best_off, last_pos);
last_pos = cur + 1;
goto _storeSequence;
}
if (opt[cur].mlen == 1)
{
litlen = opt[cur].litlen;
if (cur > litlen)
{
price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr-litlen, 0, mlen - MINMATCH);
ZSTD_LOG_TRY_PRICE("%d: TRY5 opt[%d].price=%d price=%d cur=%d litlen=%d\n", (int)(inr-base), cur - litlen, opt[cur - litlen].price, price, cur, litlen);
}
else
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, 0, mlen - MINMATCH);
}
else
{
litlen = 0;
price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, 0, mlen - MINMATCH);
ZSTD_LOG_TRY_PRICE("%d: TRY7 price=%d cur=%d litlen=0 getprice=%d\n", (int)(inr-base), price, cur, (int)ZSTD_getPrice(seqStorePtr, 0, NULL, 0, mlen - MINMATCH));
}
best_mlen = mlen;
if (faster_get_matches)
skip_num = best_mlen;
ZSTD_LOG_PARSER("%d: Found REP mlen=%d off=%d price=%d litlen=%d price[%d]=%d\n", (int)(inr-base), mlen, 0, price, litlen, cur - litlen, opt[cur - litlen].price);
do
{
if (cur + mlen > last_pos || price <= opt[cur + mlen].price) // || ((price == opt[cur + mlen].price) && (opt[cur].mlen == 1) && (cur != litlen))) // at equal price prefer REP instead of MATCH
SET_PRICE(cur + mlen, mlen, 0, litlen, price);
mlen--;
}
while (mlen >= MINMATCH);
}
if (faster_get_matches && skip_num > 0)
{
skip_num--;
continue;
}
best_mlen = (best_mlen > MINMATCH) ? best_mlen : MINMATCH;
match_num = getAllMatches(ctx, inr, ip, iend, maxSearches, mls, matches, best_mlen);
ZSTD_LOG_PARSER("%d: ZSTD_GetAllMatches match_num=%d\n", (int)(inr-base), match_num);
if (match_num > 0 && matches[match_num-1].len > sufficient_len)
{
cur -= matches[match_num-1].back;
best_mlen = matches[match_num-1].len;
best_off = matches[match_num-1].off;
last_pos = cur + 1;
goto _storeSequence;
}
// set prices using matches at position = cur
for (int i = 0; i < match_num; i++)
{
mlen = (i>0) ? matches[i-1].len+1 : best_mlen;
cur2 = cur - matches[i].back;
best_mlen = (cur2 + matches[i].len < ZSTD_OPT_NUM) ? matches[i].len : ZSTD_OPT_NUM - cur2;
ZSTD_LOG_PARSER("%d: Found1 cur=%d cur2=%d mlen=%d off=%d best_mlen=%d last_pos=%d\n", (int)(inr-base), cur, cur2, matches[i].len, matches[i].off, best_mlen, last_pos);
while (mlen <= best_mlen)
{
if (opt[cur2].mlen == 1)
{
litlen = opt[cur2].litlen;
if (cur2 > litlen)
price = opt[cur2 - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip+cur2-litlen, matches[i].off, mlen - MINMATCH);
else
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[i].off, mlen - MINMATCH);
}
else
{
litlen = 0;
price = opt[cur2].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[i].off, mlen - MINMATCH);
}
ZSTD_LOG_PARSER("%d: Found2 pred=%d mlen=%d best_mlen=%d off=%d price=%d litlen=%d price[%d]=%d\n", (int)(inr-base), matches[i].back, mlen, best_mlen, matches[i].off, price, litlen, cur - litlen, opt[cur - litlen].price);
ZSTD_LOG_TRY_PRICE("%d: TRY8 price=%d opt[%d].price=%d\n", (int)(inr-base), price, cur2 + mlen, opt[cur2 + mlen].price);
if (cur2 + mlen > last_pos || (price < opt[cur2 + mlen].price))
SET_PRICE(cur2 + mlen, mlen, matches[i].off, litlen, price);
mlen++;
}
}
} // for (skip_num = 0, cur = 1; cur <= last_pos; cur++)
best_mlen = opt[last_pos].mlen;
best_off = opt[last_pos].off;
cur = last_pos - best_mlen;
// printf("%d: start=%d best_mlen=%d best_off=%d cur=%d\n", (int)(ip - base), (int)(start - ip), (int)best_mlen, (int)best_off, cur);
/* store sequence */
_storeSequence: // cur, last_pos, best_mlen, best_off have to be set
for (int i = 1; i <= last_pos; i++)
ZSTD_LOG_PARSER("%d: price[%d/%d]=%d off=%d mlen=%d litlen=%d rep=%d rep2=%d\n", (int)(ip-base+i), i, last_pos, opt[i].price, opt[i].off, opt[i].mlen, opt[i].litlen, opt[i].rep, opt[i].rep2);
ZSTD_LOG_PARSER("%d: cur=%d/%d best_mlen=%d best_off=%d rep=%d\n", (int)(ip-base+cur), (int)cur, (int)last_pos, (int)best_mlen, (int)best_off, opt[cur].rep);
opt[0].mlen = 1;
size_t offset;
while (cur >= 0)
{
mlen = opt[cur].mlen;
ZSTD_LOG_PARSER("%d: cur=%d mlen=%d\n", (int)(ip-base), cur, mlen);
offset = opt[cur].off;
opt[cur].mlen = best_mlen;
opt[cur].off = best_off;
best_mlen = mlen;
best_off = offset;
cur -= mlen;
}
for (int i = 0; i <= last_pos;)
{
ZSTD_LOG_PARSER("%d: price2[%d/%d]=%d off=%d mlen=%d litlen=%d rep=%d rep2=%d\n", (int)(ip-base+i), i, last_pos, opt[i].price, opt[i].off, opt[i].mlen, opt[i].litlen, opt[i].rep, opt[i].rep2);
i += opt[i].mlen;
}
cur = 0;
while (cur < last_pos)
{
ZSTD_LOG_PARSER("%d: price3[%d/%d]=%d off=%d mlen=%d litlen=%d rep=%d rep2=%d\n", (int)(ip-base+cur), cur, last_pos, opt[cur].price, opt[cur].off, opt[cur].mlen, opt[cur].litlen, opt[cur].rep, opt[cur].rep2);
mlen = opt[cur].mlen;
if (mlen == 1) { ip++; cur++; continue; }
offset = opt[cur].off;
cur += mlen;
size_t litLength = ip - anchor;
ZSTD_LOG_ENCODE("%d/%d: BEFORE_ENCODE literals=%d mlen=%d off=%d rep1=%d rep2=%d\n", (int)(ip-base), (int)(iend-base), (int)(litLength), (int)mlen, (int)(offset), (int)rep_1, (int)rep_2);
if (offset)
{
rep_2 = rep_1;
rep_1 = offset;
}
else
{
if (litLength == 0)
{
best_off = rep_2;
rep_2 = rep_1;
rep_1 = best_off;
}
}
ZSTD_LOG_ENCODE("%d/%d: ENCODE literals=%d mlen=%d off=%d rep1=%d rep2=%d\n", (int)(ip-base), (int)(iend-base), (int)(litLength), (int)mlen, (int)(offset), (int)rep_1, (int)rep_2);
// printf("orig="); print_hex_text(ip, mlen, 0);
// printf("match="); print_hex_text(ip-offset, mlen, 0);
#if 0 // for debugging
size_t ml2;
if (offset)
ml2 = ZSTD_count(ip, ip-offset, iend);
else
ml2 = ZSTD_count(ip, ip-rep_1, iend);
if (ml2 < mlen && ml2 < MINMATCH)
{
printf("%d: ERROR iend=%d mlen=%d offset=%d ml2=%d\n", (int)(ip - base), (int)(iend - ip), (int)mlen, (int)offset, (int)ml2);
exit(0);
}
if (ip < anchor)
{
printf("%d: ERROR ip < anchor iend=%d mlen=%d offset=%d\n", (int)(ip - base), (int)(iend - ip), (int)mlen, (int)offset);
exit(0);
}
if (ip - offset < base)
{
printf("%d: ERROR ip - offset < base iend=%d mlen=%d offset=%d\n", (int)(ip - base), (int)(iend - ip), (int)mlen, (int)offset);
exit(0);
}
if (mlen < MINMATCH)
{
printf("%d: ERROR mlen < MINMATCH iend=%d mlen=%d offset=%d\n", (int)(ip - base), (int)(iend - ip), (int)mlen, (int)offset);
exit(0);
}
if (ip + mlen > iend)
{
printf("%d: ERROR ip + mlen >= iend iend=%d mlen=%d offset=%d\n", (int)(ip - base), (int)(iend - ip), (int)mlen, (int)offset);
exit(0);
}
#endif
ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen-MINMATCH);
ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen-MINMATCH);
anchor = ip = ip + mlen;
}
// check immediate repcode
while ( (anchor <= ilimit)
&& (MEM_read32(anchor) == MEM_read32(anchor - rep_2)) ) {
/* store sequence */
best_mlen = ZSTD_count(anchor+MINMATCH, anchor+MINMATCH-rep_2, iend);
best_off = rep_2;
rep_2 = rep_1;
rep_1 = best_off;
ZSTD_LOG_ENCODE("%d/%d: ENCODE REP literals=%d mlen=%d off=%d rep1=%d rep2=%d\n", (int)(anchor-base), (int)(iend-base), (int)(0), (int)best_mlen, (int)(0), (int)rep_1, (int)rep_2);
ZSTD_updatePrice(seqStorePtr, 0, anchor, 0, best_mlen);
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, best_mlen);
anchor += best_mlen+MINMATCH;
ip = anchor;
continue; // faster when present ... (?)
}
}
/* Last Literals */
{
size_t lastLLSize = iend - anchor;
ZSTD_LOG_ENCODE("%d: lastLLSize literals=%d\n", (int)(ip-base), (int)(lastLLSize));
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
Reference in New Issue View Git Blame Copy Permalink