/**
* Copyright (c) 2016-present, Przemyslaw Skibinski, Yann Collet, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
/* Note : this file is intended to be included within zstd_compress.c */
#ifndef ZSTD_OPT_H_91842398743
#define ZSTD_OPT_H_91842398743
#define ZSTD_LITFREQ_ADD 2
#define ZSTD_FREQ_DIV 4
#define ZSTD_MAX_PRICE (1<<30)
/*-*************************************
* Price functions for optimal parser
***************************************/
FORCE_INLINE void ZSTD_setLog2Prices(seqStore_t* ssPtr)
{
ssPtr->log2matchLengthSum = ZSTD_highbit32(ssPtr->matchLengthSum+1);
ssPtr->log2litLengthSum = ZSTD_highbit32(ssPtr->litLengthSum+1);
ssPtr->log2litSum = ZSTD_highbit32(ssPtr->litSum+1);
ssPtr->log2offCodeSum = ZSTD_highbit32(ssPtr->offCodeSum+1);
ssPtr->factor = 1 + ((ssPtr->litSum>>5) / ssPtr->litLengthSum) + ((ssPtr->litSum<<1) / (ssPtr->litSum + ssPtr->matchSum));
}
MEM_STATIC void ZSTD_rescaleFreqs(seqStore_t* ssPtr, const BYTE* src, size_t srcSize)
{
unsigned u;
ssPtr->cachedLiterals = NULL;
ssPtr->cachedPrice = ssPtr->cachedLitLength = 0;
ssPtr->staticPrices = 0;
if (ssPtr->litLengthSum == 0) {
if (srcSize <= 1024) ssPtr->staticPrices = 1;
for (u=0; u<=MaxLit; u++)
ssPtr->litFreq[u] = 0;
for (u=0; u<srcSize; u++)
ssPtr->litFreq[src[u]]++;
ssPtr->litSum = 0;
ssPtr->litLengthSum = MaxLL+1;
ssPtr->matchLengthSum = MaxML+1;
ssPtr->offCodeSum = (MaxOff+1);
ssPtr->matchSum = (ZSTD_LITFREQ_ADD<<Litbits);
for (u=0; u<=MaxLit; u++) {
ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u]>>ZSTD_FREQ_DIV);
ssPtr->litSum += ssPtr->litFreq[u];
}
for (u=0; u<=MaxLL; u++)
ssPtr->litLengthFreq[u] = 1;
for (u=0; u<=MaxML; u++)
ssPtr->matchLengthFreq[u] = 1;
for (u=0; u<=MaxOff; u++)
ssPtr->offCodeFreq[u] = 1;
} else {
ssPtr->matchLengthSum = 0;
ssPtr->litLengthSum = 0;
ssPtr->offCodeSum = 0;
ssPtr->matchSum = 0;
ssPtr->litSum = 0;
for (u=0; u<=MaxLit; u++) {
ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u]>>(ZSTD_FREQ_DIV+1));
ssPtr->litSum += ssPtr->litFreq[u];
}
for (u=0; u<=MaxLL; u++) {
ssPtr->litLengthFreq[u] = 1 + (ssPtr->litLengthFreq[u]>>(ZSTD_FREQ_DIV+1));
ssPtr->litLengthSum += ssPtr->litLengthFreq[u];
}
for (u=0; u<=MaxML; u++) {
ssPtr->matchLengthFreq[u] = 1 + (ssPtr->matchLengthFreq[u]>>ZSTD_FREQ_DIV);
ssPtr->matchLengthSum += ssPtr->matchLengthFreq[u];
ssPtr->matchSum += ssPtr->matchLengthFreq[u] * (u + 3);
}
ssPtr->matchSum *= ZSTD_LITFREQ_ADD;
for (u=0; u<=MaxOff; u++) {
ssPtr->offCodeFreq[u] = 1 + (ssPtr->offCodeFreq[u]>>ZSTD_FREQ_DIV);
ssPtr->offCodeSum += ssPtr->offCodeFreq[u];
}
}
ZSTD_setLog2Prices(ssPtr);
}
FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t* ssPtr, U32 litLength, const BYTE* literals)
{
U32 price, u;
if (ssPtr->staticPrices)
return ZSTD_highbit32((U32)litLength+1) + (litLength*6);
if (litLength == 0)
return ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[0]+1);
/* literals */
if (ssPtr->cachedLiterals == literals) {
U32 const additional = litLength - ssPtr->cachedLitLength;
const BYTE* literals2 = ssPtr->cachedLiterals + ssPtr->cachedLitLength;
price = ssPtr->cachedPrice + additional * ssPtr->log2litSum;
for (u=0; u < additional; u++)
price -= ZSTD_highbit32(ssPtr->litFreq[literals2[u]]+1);
ssPtr->cachedPrice = price;
ssPtr->cachedLitLength = litLength;
} else {
price = litLength * ssPtr->log2litSum;
for (u=0; u < litLength; u++)
price -= ZSTD_highbit32(ssPtr->litFreq[literals[u]]+1);
if (litLength >= 12) {
ssPtr->cachedLiterals = literals;
ssPtr->cachedPrice = price;
ssPtr->cachedLitLength = litLength;
}
}
/* literal Length */
{ const BYTE LL_deltaCode = 19;
const BYTE llCode = (litLength>63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength];
price += LL_bits[llCode] + ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[llCode]+1);
}
return price;
}
FORCE_INLINE U32 ZSTD_getPrice(seqStore_t* seqStorePtr, U32 litLength, const BYTE* literals, U32 offset, U32 matchLength, const int ultra)
{
/* offset */
U32 price;
BYTE const offCode = (BYTE)ZSTD_highbit32(offset+1);
if (seqStorePtr->staticPrices)
return ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit32((U32)matchLength+1) + 16 + offCode;
price = offCode + seqStorePtr->log2offCodeSum - ZSTD_highbit32(seqStorePtr->offCodeFreq[offCode]+1);
if (!ultra && offCode >= 20) price += (offCode-19)*2;
/* match Length */
{ const BYTE ML_deltaCode = 36;
const BYTE mlCode = (matchLength>127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength];
price += ML_bits[mlCode] + seqStorePtr->log2matchLengthSum - ZSTD_highbit32(seqStorePtr->matchLengthFreq[mlCode]+1);
}
return price + ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + seqStorePtr->factor;
}
MEM_STATIC void ZSTD_updatePrice(seqStore_t* seqStorePtr, U32 litLength, const BYTE* literals, U32 offset, U32 matchLength)
{
U32 u;
/* literals */
seqStorePtr->litSum += litLength*ZSTD_LITFREQ_ADD;
for (u=0; u < litLength; u++)
seqStorePtr->litFreq[literals[u]] += ZSTD_LITFREQ_ADD;
/* literal Length */
{ const BYTE LL_deltaCode = 19;
const BYTE llCode = (litLength>63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength];
seqStorePtr->litLengthFreq[llCode]++;
seqStorePtr->litLengthSum++;
}
/* match offset */
{ BYTE const offCode = (BYTE)ZSTD_highbit32(offset+1);
seqStorePtr->offCodeSum++;
seqStorePtr->offCodeFreq[offCode]++;
}
/* match Length */
{ const BYTE ML_deltaCode = 36;
const BYTE mlCode = (matchLength>127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength];
seqStorePtr->matchLengthFreq[mlCode]++;
seqStorePtr->matchLengthSum++;
}
ZSTD_setLog2Prices(seqStorePtr);
}
#define SET_PRICE(pos, mlen_, offset_, litlen_, price_) \
{ \
while (last_pos < pos) { opt[last_pos+1].price = ZSTD_MAX_PRICE; last_pos++; } \
opt[pos].mlen = mlen_; \
opt[pos].off = offset_; \
opt[pos].litlen = litlen_; \
opt[pos].price = price_; \
}
/* 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];
}
/*-*************************************
* Binary Tree search
***************************************/
static U32 ZSTD_insertBtAndGetAllMatches (
ZSTD_CCtx* zc,
const BYTE* const ip, const BYTE* const iLimit,
U32 nbCompares, const U32 mls,
U32 extDict, ZSTD_match_t* matches, const U32 minMatchLen)
{
const BYTE* const base = zc->base;
const U32 current = (U32)(ip-base);
const U32 hashLog = zc->params.cParams.hashLog;
const size_t h = ZSTD_hashPtr(ip, hashLog, mls);
U32* const hashTable = zc->hashTable;
U32 matchIndex = hashTable[h];
U32* const bt = zc->chainTable;
const U32 btLog = zc->params.cParams.chainLog - 1;
const U32 btMask= (1U << btLog) - 1;
size_t commonLengthSmaller=0, commonLengthLarger=0;
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 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 */
U32 mnum = 0;
const U32 minMatch = (mls == 3) ? 3 : 4;
size_t bestLength = minMatchLen-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, iLimit);
} 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 > bestLength) {
bestLength = currentMl;
matches[mnum].off = ZSTD_REP_MOVE_OPT + current - matchIndex3;
matches[mnum].len = (U32)currentMl;
mnum++;
if (currentMl > ZSTD_OPT_NUM) goto update;
if (ip+currentMl == iLimit) goto update; /* best possible, and avoid read overflow*/
}
}
}
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, iLimit) +1;
}
} else {
match = dictBase + matchIndex;
matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iLimit, 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;
bestLength = matchLength;
matches[mnum].off = ZSTD_REP_MOVE_OPT + current - matchIndex;
matches[mnum].len = (U32)matchLength;
mnum++;
if (matchLength > ZSTD_OPT_NUM) break;
if (ip+matchLength == iLimit) /* 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;
update:
zc->nextToUpdate = (matchEndIdx > current + 8) ? matchEndIdx - 8 : current+1;
return mnum;
}
/** Tree updater, providing best match */
static U32 ZSTD_BtGetAllMatches (
ZSTD_CCtx* zc,
const BYTE* const ip, const BYTE* const iLimit,
const U32 maxNbAttempts, const U32 mls, ZSTD_match_t* matches, const U32 minMatchLen)
{
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, minMatchLen);
}
static U32 ZSTD_BtGetAllMatches_selectMLS (
ZSTD_CCtx* zc, /* Index table will be updated */
const BYTE* ip, const BYTE* const iHighLimit,
const U32 maxNbAttempts, const U32 matchLengthSearch, ZSTD_match_t* matches, const U32 minMatchLen)
{
switch(matchLengthSearch)
{
case 3 : return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen);
default :
case 4 : return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen);
case 5 : return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen);
case 6 : return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen);
}
}
/** Tree updater, providing best match */
static U32 ZSTD_BtGetAllMatches_extDict (
ZSTD_CCtx* zc,
const BYTE* const ip, const BYTE* const iLimit,
const U32 maxNbAttempts, const U32 mls, ZSTD_match_t* matches, const U32 minMatchLen)
{
if (ip < zc->base + zc->nextToUpdate) return 0; /* skipped area */
ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls);
return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 1, matches, minMatchLen);
}
static U32 ZSTD_BtGetAllMatches_selectMLS_extDict (
ZSTD_CCtx* zc, /* Index table will be updated */
const BYTE* ip, const BYTE* const iHighLimit,
const U32 maxNbAttempts, const U32 matchLengthSearch, ZSTD_match_t* matches, const U32 minMatchLen)
{
switch(matchLengthSearch)
{
case 3 : return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen);
default :
case 4 : return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen);
case 5 : return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen);
case 6 : return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen);
}
}
/*-*******************************
* Optimal parser
*********************************/
FORCE_INLINE
void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
const void* src, size_t srcSize, const int ultra)
{
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 BYTE* const prefixStart = base + ctx->dictLimit;
const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
const U32 sufficient_len = ctx->params.cParams.targetLength;
const U32 mls = ctx->params.cParams.searchLength;
const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
ZSTD_optimal_t* opt = seqStorePtr->priceTable;
ZSTD_match_t* matches = seqStorePtr->matchTable;
const BYTE* inr;
U32 offset, rep[ZSTD_REP_NUM];
/* init */
ctx->nextToUpdate3 = ctx->nextToUpdate;
ZSTD_rescaleFreqs(seqStorePtr, (const BYTE*)src, srcSize);
ip += (ip==prefixStart);
{ U32 i; for (i=0; i<ZSTD_REP_NUM; i++) rep[i]=ctx->rep[i]; }
/* Match Loop */
while (ip < ilimit) {
U32 cur, match_num, last_pos, litlen, price;
U32 u, mlen, best_mlen, best_off, litLength;
memset(opt, 0, sizeof(ZSTD_optimal_t));
last_pos = 0;
litlen = (U32)(ip - anchor);
/* check repCode */
{ U32 i, last_i = ZSTD_REP_CHECK + (ip==anchor);
for (i=(ip == anchor); i<last_i; i++) {
const S32 repCur = (i==ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
if ( (repCur > 0) && (repCur < (S32)(ip-prefixStart))
&& (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(ip - repCur, minMatch))) {
mlen = (U32)ZSTD_count(ip+minMatch, ip+minMatch-repCur, iend) + minMatch;
if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
best_mlen = mlen; best_off = i; cur = 0; last_pos = 1;
goto _storeSequence;
}
best_off = i - (ip == anchor);
do {
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
if (mlen > last_pos || price < opt[mlen].price)
SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
mlen--;
} while (mlen >= minMatch);
} } }
match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, ip, iend, maxSearches, mls, matches, minMatch);
if (!last_pos && !match_num) { ip++; continue; }
if (match_num && (matches[match_num-1].len > sufficient_len || matches[match_num-1].len >= ZSTD_OPT_NUM)) {
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 */
best_mlen = (last_pos) ? last_pos : minMatch;
for (u = 0; u < match_num; u++) {
mlen = (u>0) ? matches[u-1].len+1 : best_mlen;
best_mlen = matches[u].len;
while (mlen <= best_mlen) {
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off-1, mlen - MINMATCH, ultra);
if (mlen > last_pos || price < opt[mlen].price)
SET_PRICE(mlen, mlen, matches[u].off, litlen, price); /* note : macro modifies last_pos */
mlen++;
} }
if (last_pos < minMatch) { ip++; continue; }
/* initialize opt[0] */
{ U32 i ; for (i=0; i<ZSTD_REP_NUM; i++) opt[0].rep[i] = rep[i]; }
opt[0].mlen = 1;
opt[0].litlen = litlen;
/* check further positions */
for (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);
} else
price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
} else {
litlen = 1;
price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr-1);
}
if (cur > last_pos || price <= opt[cur].price)
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].off > ZSTD_REP_MOVE_OPT) {
opt[cur].rep[2] = opt[cur-mlen].rep[1];
opt[cur].rep[1] = opt[cur-mlen].rep[0];
opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT;
} else {
opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur-mlen].rep[1] : opt[cur-mlen].rep[2];
opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur-mlen].rep[0] : opt[cur-mlen].rep[1];
opt[cur].rep[0] = ((opt[cur].off==ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur-mlen].rep[0] - 1) : (opt[cur-mlen].rep[opt[cur].off]);
}
best_mlen = minMatch;
{ U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1);
for (i=(opt[cur].mlen != 1); i<last_i; i++) { /* check rep */
const S32 repCur = (i==ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
if ( (repCur > 0) && (repCur < (S32)(inr-prefixStart))
&& (MEM_readMINMATCH(inr, minMatch) == MEM_readMINMATCH(inr - repCur, minMatch))) {
mlen = (U32)ZSTD_count(inr+minMatch, inr+minMatch - repCur, iend) + minMatch;
if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
best_mlen = mlen; best_off = i; last_pos = cur + 1;
goto _storeSequence;
}
best_off = i - (opt[cur].mlen != 1);
if (mlen > best_mlen) best_mlen = mlen;
do {
if (opt[cur].mlen == 1) {
litlen = opt[cur].litlen;
if (cur > litlen) {
price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr-litlen, best_off, mlen - MINMATCH, ultra);
} else
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
} else {
litlen = 0;
price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra);
}
if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
SET_PRICE(cur + mlen, mlen, i, litlen, price);
mlen--;
} while (mlen >= minMatch);
} } }
match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, inr, iend, maxSearches, mls, matches, best_mlen);
if (match_num > 0 && (matches[match_num-1].len > sufficient_len || cur + matches[match_num-1].len >= ZSTD_OPT_NUM)) {
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 (u = 0; u < match_num; u++) {
mlen = (u>0) ? matches[u-1].len+1 : best_mlen;
best_mlen = matches[u].len;
while (mlen <= best_mlen) {
if (opt[cur].mlen == 1) {
litlen = opt[cur].litlen;
if (cur > litlen)
price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip+cur-litlen, matches[u].off-1, mlen - MINMATCH, ultra);
else
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off-1, mlen - MINMATCH, ultra);
} else {
litlen = 0;
price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off-1, mlen - MINMATCH, ultra);
}
if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
mlen++;
} } }
best_mlen = opt[last_pos].mlen;
best_off = opt[last_pos].off;
cur = last_pos - best_mlen;
/* store sequence */
_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */
opt[0].mlen = 1;
while (1) {
mlen = opt[cur].mlen;
offset = opt[cur].off;
opt[cur].mlen = best_mlen;
opt[cur].off = best_off;
best_mlen = mlen;
best_off = offset;
if (mlen > cur) break;
cur -= mlen;
}
for (u = 0; u <= last_pos;) {
u += opt[u].mlen;
}
for (cur=0; cur < last_pos; ) {
mlen = opt[cur].mlen;
if (mlen == 1) { ip++; cur++; continue; }
offset = opt[cur].off;
cur += mlen;
litLength = (U32)(ip - anchor);
if (offset > ZSTD_REP_MOVE_OPT) {
rep[2] = rep[1];
rep[1] = rep[0];
rep[0] = offset - ZSTD_REP_MOVE_OPT;
offset--;
} else {
if (offset != 0) {
best_off = (offset==ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]);
if (offset != 1) rep[2] = rep[1];
rep[1] = rep[0];
rep[0] = best_off;
}
if (litLength==0) offset--;
}
ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen-MINMATCH);
ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen-MINMATCH);
anchor = ip = ip + mlen;
} } /* for (cur=0; cur < last_pos; ) */
/* Save reps for next block */
{ int i; for (i=0; i<ZSTD_REP_NUM; i++) ctx->savedRep[i] = rep[i]; }
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
FORCE_INLINE
void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
const void* src, size_t srcSize, const int ultra)
{
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 lowestIndex = ctx->lowLimit;
const U32 dictLimit = ctx->dictLimit;
const BYTE* const prefixStart = base + dictLimit;
const BYTE* const dictBase = ctx->dictBase;
const BYTE* const dictEnd = dictBase + dictLimit;
const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
const U32 sufficient_len = ctx->params.cParams.targetLength;
const U32 mls = ctx->params.cParams.searchLength;
const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
ZSTD_optimal_t* opt = seqStorePtr->priceTable;
ZSTD_match_t* matches = seqStorePtr->matchTable;
const BYTE* inr;
/* init */
U32 offset, rep[ZSTD_REP_NUM];
{ U32 i; for (i=0; i<ZSTD_REP_NUM; i++) rep[i]=ctx->rep[i]; }
ctx->nextToUpdate3 = ctx->nextToUpdate;
ZSTD_rescaleFreqs(seqStorePtr, (const BYTE*)src, srcSize);
ip += (ip==prefixStart);
/* Match Loop */
while (ip < ilimit) {
U32 cur, match_num, last_pos, litlen, price;
U32 u, mlen, best_mlen, best_off, litLength;
U32 current = (U32)(ip-base);
memset(opt, 0, sizeof(ZSTD_optimal_t));
last_pos = 0;
opt[0].litlen = (U32)(ip - anchor);
/* check repCode */
{ U32 i, last_i = ZSTD_REP_CHECK + (ip==anchor);
for (i = (ip==anchor); i<last_i; i++) {
const S32 repCur = (i==ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
const U32 repIndex = (U32)(current - repCur);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ( (repCur > 0 && repCur <= (S32)current)
&& (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex>lowestIndex)) /* intentional overflow */
&& (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) ) {
/* repcode detected we should take it */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
mlen = (U32)ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
best_mlen = mlen; best_off = i; cur = 0; last_pos = 1;
goto _storeSequence;
}
best_off = i - (ip==anchor);
litlen = opt[0].litlen;
do {
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
if (mlen > last_pos || price < opt[mlen].price)
SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
mlen--;
} while (mlen >= minMatch);
} } }
match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, ip, iend, maxSearches, mls, matches, minMatch); /* first search (depth 0) */
if (!last_pos && !match_num) { ip++; continue; }
{ U32 i; for (i=0; i<ZSTD_REP_NUM; i++) opt[0].rep[i] = rep[i]; }
opt[0].mlen = 1;
if (match_num && (matches[match_num-1].len > sufficient_len || matches[match_num-1].len >= ZSTD_OPT_NUM)) {
best_mlen = matches[match_num-1].len;
best_off = matches[match_num-1].off;
cur = 0;
last_pos = 1;
goto _storeSequence;
}
best_mlen = (last_pos) ? last_pos : minMatch;
/* set prices using matches at position = 0 */
for (u = 0; u < match_num; u++) {
mlen = (u>0) ? matches[u-1].len+1 : best_mlen;
best_mlen = matches[u].len;
litlen = opt[0].litlen;
while (mlen <= best_mlen) {
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off-1, mlen - MINMATCH, ultra);
if (mlen > last_pos || price < opt[mlen].price)
SET_PRICE(mlen, mlen, matches[u].off, litlen, price);
mlen++;
} }
if (last_pos < minMatch) {
ip++; continue;
}
/* check further positions */
for (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);
} else
price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
} else {
litlen = 1;
price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr-1);
}
if (cur > last_pos || price <= opt[cur].price)
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].off > ZSTD_REP_MOVE_OPT) {
opt[cur].rep[2] = opt[cur-mlen].rep[1];
opt[cur].rep[1] = opt[cur-mlen].rep[0];
opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT;
} else {
opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur-mlen].rep[1] : opt[cur-mlen].rep[2];
opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur-mlen].rep[0] : opt[cur-mlen].rep[1];
opt[cur].rep[0] = ((opt[cur].off==ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur-mlen].rep[0] - 1) : (opt[cur-mlen].rep[opt[cur].off]);
}
best_mlen = minMatch;
{ U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1);
for (i = (mlen != 1); i<last_i; i++) {
const S32 repCur = (i==ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
const U32 repIndex = (U32)(current+cur - repCur);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ( (repCur > 0 && repCur <= (S32)(current+cur))
&& (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex>lowestIndex)) /* intentional overflow */
&& (MEM_readMINMATCH(inr, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) ) {
/* repcode detected */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
mlen = (U32)ZSTD_count_2segments(inr+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
best_mlen = mlen; best_off = i; last_pos = cur + 1;
goto _storeSequence;
}
best_off = i - (opt[cur].mlen != 1);
if (mlen > best_mlen) best_mlen = mlen;
do {
if (opt[cur].mlen == 1) {
litlen = opt[cur].litlen;
if (cur > litlen) {
price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr-litlen, best_off, mlen - MINMATCH, ultra);
} else
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
} else {
litlen = 0;
price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra);
}
if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
SET_PRICE(cur + mlen, mlen, i, litlen, price);
mlen--;
} while (mlen >= minMatch);
} } }
match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, inr, iend, maxSearches, mls, matches, minMatch);
if (match_num > 0 && matches[match_num-1].len > sufficient_len) {
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 (u = 0; u < match_num; u++) {
mlen = (u>0) ? matches[u-1].len+1 : best_mlen;
best_mlen = (cur + matches[u].len < ZSTD_OPT_NUM) ? matches[u].len : ZSTD_OPT_NUM - cur;
while (mlen <= best_mlen) {
if (opt[cur].mlen == 1) {
litlen = opt[cur].litlen;
if (cur > litlen)
price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip+cur-litlen, matches[u].off-1, mlen - MINMATCH, ultra);
else
price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off-1, mlen - MINMATCH, ultra);
} else {
litlen = 0;
price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off-1, mlen - MINMATCH, ultra);
}
if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
mlen++;
} } } /* for (cur = 1; cur <= last_pos; cur++) */
best_mlen = opt[last_pos].mlen;
best_off = opt[last_pos].off;
cur = last_pos - best_mlen;
/* store sequence */
_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */
opt[0].mlen = 1;
while (1) {
mlen = opt[cur].mlen;
offset = opt[cur].off;
opt[cur].mlen = best_mlen;
opt[cur].off = best_off;
best_mlen = mlen;
best_off = offset;
if (mlen > cur) break;
cur -= mlen;
}
for (u = 0; u <= last_pos; ) {
u += opt[u].mlen;
}
for (cur=0; cur < last_pos; ) {
mlen = opt[cur].mlen;
if (mlen == 1) { ip++; cur++; continue; }
offset = opt[cur].off;
cur += mlen;
litLength = (U32)(ip - anchor);
if (offset > ZSTD_REP_MOVE_OPT) {
rep[2] = rep[1];
rep[1] = rep[0];
rep[0] = offset - ZSTD_REP_MOVE_OPT;
offset--;
} else {
if (offset != 0) {
best_off = (offset==ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]);
if (offset != 1) rep[2] = rep[1];
rep[1] = rep[0];
rep[0] = best_off;
}
if (litLength==0) offset--;
}
ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen-MINMATCH);
ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen-MINMATCH);
anchor = ip = ip + mlen;
} } /* for (cur=0; cur < last_pos; ) */
/* Save reps for next block */
{ int i; for (i=0; i<ZSTD_REP_NUM; i++) ctx->savedRep[i] = rep[i]; }
/* Last Literals */
{ size_t lastLLSize = iend - anchor;
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
#endif /* ZSTD_OPT_H_91842398743 */