| /* |
| ZSTD Optimal mode |
| Copyright (C) 2016, Przemyslaw Skibinski, Yann Collet. |
| |
| BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions are |
| met: |
| |
| * Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| * Redistributions in binary form must reproduce the above |
| copyright notice, this list of conditions and the following disclaimer |
| in the documentation and/or other materials provided with the |
| distribution. |
| |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| You can contact the author at : |
| - Zstd source repository : https://www.zstd.net |
| */ |
| |
| /* Note : this file is intended to be included within zstd_compress.c */ |
| |
| |
| #ifndef ZSTD_OPT_H_91842398743 |
| #define ZSTD_OPT_H_91842398743 |
| |
| |
| #define ZSTD_FREQ_DIV 5 |
| |
| /*-************************************* |
| * 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) |
| { |
| unsigned u; |
| |
| ssPtr->cachedLiterals = NULL; |
| ssPtr->cachedPrice = ssPtr->cachedLitLength = 0; |
| |
| if (ssPtr->litLengthSum == 0) { |
| ssPtr->litSum = (2<<Litbits); |
| ssPtr->litLengthSum = MaxLL+1; |
| ssPtr->matchLengthSum = MaxML+1; |
| ssPtr->offCodeSum = (MaxOff+1); |
| ssPtr->matchSum = (2<<Litbits); |
| |
| for (u=0; u<=MaxLit; u++) |
| ssPtr->litFreq[u] = 2; |
| 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); |
| ssPtr->litSum += ssPtr->litFreq[u]; |
| } |
| for (u=0; u<=MaxLL; u++) { |
| ssPtr->litLengthFreq[u] = 1 + (ssPtr->litLengthFreq[u]>>ZSTD_FREQ_DIV); |
| 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); |
| } |
| 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 (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) |
| { |
| /* offset */ |
| BYTE const offCode = (BYTE)ZSTD_highbit32(offset+1); |
| U32 price = offCode + seqStorePtr->log2offCodeSum - ZSTD_highbit32(seqStorePtr->offCodeFreq[offCode]+1); |
| |
| /* 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; |
| for (u=0; u < litLength; u++) |
| seqStorePtr->litFreq[literals[u]]++; |
| |
| /* 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 = 1<<30; 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) |
| { |
| 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); |
| ip += (ip==prefixStart); |
| { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) rep[i]=ctx->rep[i]; } |
| inr = ip; |
| |
| /* 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) && (ip==anchor)) ? (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); |
| 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); |
| 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].mlen != 1)) ? (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 (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); |
| } else |
| price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH); |
| } else { |
| litlen = 0; |
| price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH); |
| } |
| |
| if (mlen > best_mlen) best_mlen = mlen; |
| |
| do { |
| 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); |
| else |
| price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off-1, mlen - MINMATCH); |
| } else { |
| litlen = 0; |
| price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off-1, mlen - MINMATCH); |
| } |
| |
| 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) && (litLength==0)) ? (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) |
| { |
| 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); |
| ip += (ip==prefixStart); |
| inr = ip; |
| |
| /* 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; |
| inr = ip; |
| 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) && (ip==anchor)) ? (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); |
| 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); |
| 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 = 0; |
| |
| { 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].mlen != 1)) ? (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 (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); |
| } else |
| price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH); |
| } else { |
| litlen = 0; |
| price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH); |
| } |
| |
| best_mlen = mlen; |
| |
| do { |
| 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; |
| } |
| |
| best_mlen = (best_mlen > minMatch) ? best_mlen : minMatch; |
| |
| /* 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); |
| else |
| price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off-1, mlen - MINMATCH); |
| } else { |
| litlen = 0; |
| price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off-1, mlen - MINMATCH); |
| } |
| |
| 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) && (litLength==0)) ? (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 */ |
