--- /dev/null
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+#include "zstd_compress_internal.h"
+#include "hist.h"
+#include "zstd_opt.h"
+
+
+#define ZSTD_LITFREQ_ADD 2 /* scaling factor for litFreq, so that frequencies adapt faster to new stats */
+#define ZSTD_MAX_PRICE (1<<30)
+
+#define ZSTD_PREDEF_THRESHOLD 8 /* if srcSize < ZSTD_PREDEF_THRESHOLD, symbols' cost is assumed static, directly determined by pre-defined distributions */
+
+
+/*-*************************************
+* Price functions for optimal parser
+***************************************/
+
+#if 0 /* approximation at bit level (for tests) */
+# define BITCOST_ACCURACY 0
+# define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
+# define WEIGHT(stat, opt) ((void)(opt), ZSTD_bitWeight(stat))
+#elif 0 /* fractional bit accuracy (for tests) */
+# define BITCOST_ACCURACY 8
+# define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
+# define WEIGHT(stat,opt) ((void)(opt), ZSTD_fracWeight(stat))
+#else /* opt==approx, ultra==accurate */
+# define BITCOST_ACCURACY 8
+# define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
+# define WEIGHT(stat,opt) ((opt) ? ZSTD_fracWeight(stat) : ZSTD_bitWeight(stat))
+#endif
+
+/* ZSTD_bitWeight() :
+ * provide estimated "cost" of a stat in full bits only */
+MEM_STATIC U32 ZSTD_bitWeight(U32 stat)
+{
+ return (ZSTD_highbit32(stat+1) * BITCOST_MULTIPLIER);
+}
+
+/* ZSTD_fracWeight() :
+ * provide fractional-bit "cost" of a stat,
+ * using linear interpolation approximation */
+MEM_STATIC U32 ZSTD_fracWeight(U32 rawStat)
+{
+ U32 const stat = rawStat + 1;
+ U32 const hb = ZSTD_highbit32(stat);
+ U32 const BWeight = hb * BITCOST_MULTIPLIER;
+ /* Fweight was meant for "Fractional weight"
+ * but it's effectively a value between 1 and 2
+ * using fixed point arithmetic */
+ U32 const FWeight = (stat << BITCOST_ACCURACY) >> hb;
+ U32 const weight = BWeight + FWeight;
+ assert(hb + BITCOST_ACCURACY < 31);
+ return weight;
+}
+
+#if (DEBUGLEVEL>=2)
+/* debugging function,
+ * @return price in bytes as fractional value
+ * for debug messages only */
+MEM_STATIC double ZSTD_fCost(int price)
+{
+ return (double)price / (BITCOST_MULTIPLIER*8);
+}
+#endif
+
+static int ZSTD_compressedLiterals(optState_t const* const optPtr)
+{
+ return optPtr->literalCompressionMode != ZSTD_ps_disable;
+}
+
+static void ZSTD_setBasePrices(optState_t* optPtr, int optLevel)
+{
+ if (ZSTD_compressedLiterals(optPtr))
+ optPtr->litSumBasePrice = WEIGHT(optPtr->litSum, optLevel);
+ optPtr->litLengthSumBasePrice = WEIGHT(optPtr->litLengthSum, optLevel);
+ optPtr->matchLengthSumBasePrice = WEIGHT(optPtr->matchLengthSum, optLevel);
+ optPtr->offCodeSumBasePrice = WEIGHT(optPtr->offCodeSum, optLevel);
+}
+
+
+static U32 sum_u32(const unsigned table[], size_t nbElts)
+{
+ size_t n;
+ U32 total = 0;
+ for (n=0; n<nbElts; n++) {
+ total += table[n];
+ }
+ return total;
+}
+
+typedef enum { base_0possible=0, base_1guaranteed=1 } base_directive_e;
+
+static U32
+ZSTD_downscaleStats(unsigned* table, U32 lastEltIndex, U32 shift, base_directive_e base1)
+{
+ U32 s, sum=0;
+ DEBUGLOG(5, "ZSTD_downscaleStats (nbElts=%u, shift=%u)",
+ (unsigned)lastEltIndex+1, (unsigned)shift );
+ assert(shift < 30);
+ for (s=0; s<lastEltIndex+1; s++) {
+ unsigned const base = base1 ? 1 : (table[s]>0);
+ unsigned const newStat = base + (table[s] >> shift);
+ sum += newStat;
+ table[s] = newStat;
+ }
+ return sum;
+}
+
+/* ZSTD_scaleStats() :
+ * reduce all elt frequencies in table if sum too large
+ * return the resulting sum of elements */
+static U32 ZSTD_scaleStats(unsigned* table, U32 lastEltIndex, U32 logTarget)
+{
+ U32 const prevsum = sum_u32(table, lastEltIndex+1);
+ U32 const factor = prevsum >> logTarget;
+ DEBUGLOG(5, "ZSTD_scaleStats (nbElts=%u, target=%u)", (unsigned)lastEltIndex+1, (unsigned)logTarget);
+ assert(logTarget < 30);
+ if (factor <= 1) return prevsum;
+ return ZSTD_downscaleStats(table, lastEltIndex, ZSTD_highbit32(factor), base_1guaranteed);
+}
+
+/* ZSTD_rescaleFreqs() :
+ * if first block (detected by optPtr->litLengthSum == 0) : init statistics
+ * take hints from dictionary if there is one
+ * and init from zero if there is none,
+ * using src for literals stats, and baseline stats for sequence symbols
+ * otherwise downscale existing stats, to be used as seed for next block.
+ */
+static void
+ZSTD_rescaleFreqs(optState_t* const optPtr,
+ const BYTE* const src, size_t const srcSize,
+ int const optLevel)
+{
+ int const compressedLiterals = ZSTD_compressedLiterals(optPtr);
+ DEBUGLOG(5, "ZSTD_rescaleFreqs (srcSize=%u)", (unsigned)srcSize);
+ optPtr->priceType = zop_dynamic;
+
+ if (optPtr->litLengthSum == 0) { /* no literals stats collected -> first block assumed -> init */
+
+ /* heuristic: use pre-defined stats for too small inputs */
+ if (srcSize <= ZSTD_PREDEF_THRESHOLD) {
+ DEBUGLOG(5, "srcSize <= %i : use predefined stats", ZSTD_PREDEF_THRESHOLD);
+ optPtr->priceType = zop_predef;
+ }
+
+ assert(optPtr->symbolCosts != NULL);
+ if (optPtr->symbolCosts->huf.repeatMode == HUF_repeat_valid) {
+
+ /* huffman stats covering the full value set : table presumed generated by dictionary */
+ optPtr->priceType = zop_dynamic;
+
+ if (compressedLiterals) {
+ /* generate literals statistics from huffman table */
+ unsigned lit;
+ assert(optPtr->litFreq != NULL);
+ optPtr->litSum = 0;
+ for (lit=0; lit<=MaxLit; lit++) {
+ U32 const scaleLog = 11; /* scale to 2K */
+ U32 const bitCost = HUF_getNbBitsFromCTable(optPtr->symbolCosts->huf.CTable, lit);
+ assert(bitCost <= scaleLog);
+ optPtr->litFreq[lit] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/;
+ optPtr->litSum += optPtr->litFreq[lit];
+ } }
+
+ { unsigned ll;
+ FSE_CState_t llstate;
+ FSE_initCState(&llstate, optPtr->symbolCosts->fse.litlengthCTable);
+ optPtr->litLengthSum = 0;
+ for (ll=0; ll<=MaxLL; ll++) {
+ U32 const scaleLog = 10; /* scale to 1K */
+ U32 const bitCost = FSE_getMaxNbBits(llstate.symbolTT, ll);
+ assert(bitCost < scaleLog);
+ optPtr->litLengthFreq[ll] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/;
+ optPtr->litLengthSum += optPtr->litLengthFreq[ll];
+ } }
+
+ { unsigned ml;
+ FSE_CState_t mlstate;
+ FSE_initCState(&mlstate, optPtr->symbolCosts->fse.matchlengthCTable);
+ optPtr->matchLengthSum = 0;
+ for (ml=0; ml<=MaxML; ml++) {
+ U32 const scaleLog = 10;
+ U32 const bitCost = FSE_getMaxNbBits(mlstate.symbolTT, ml);
+ assert(bitCost < scaleLog);
+ optPtr->matchLengthFreq[ml] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/;
+ optPtr->matchLengthSum += optPtr->matchLengthFreq[ml];
+ } }
+
+ { unsigned of;
+ FSE_CState_t ofstate;
+ FSE_initCState(&ofstate, optPtr->symbolCosts->fse.offcodeCTable);
+ optPtr->offCodeSum = 0;
+ for (of=0; of<=MaxOff; of++) {
+ U32 const scaleLog = 10;
+ U32 const bitCost = FSE_getMaxNbBits(ofstate.symbolTT, of);
+ assert(bitCost < scaleLog);
+ optPtr->offCodeFreq[of] = bitCost ? 1 << (scaleLog-bitCost) : 1 /*minimum to calculate cost*/;
+ optPtr->offCodeSum += optPtr->offCodeFreq[of];
+ } }
+
+ } else { /* first block, no dictionary */
+
+ assert(optPtr->litFreq != NULL);
+ if (compressedLiterals) {
+ /* base initial cost of literals on direct frequency within src */
+ unsigned lit = MaxLit;
+ HIST_count_simple(optPtr->litFreq, &lit, src, srcSize); /* use raw first block to init statistics */
+ optPtr->litSum = ZSTD_downscaleStats(optPtr->litFreq, MaxLit, 8, base_0possible);
+ }
+
+ { unsigned const baseLLfreqs[MaxLL+1] = {
+ 4, 2, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1
+ };
+ ZSTD_memcpy(optPtr->litLengthFreq, baseLLfreqs, sizeof(baseLLfreqs));
+ optPtr->litLengthSum = sum_u32(baseLLfreqs, MaxLL+1);
+ }
+
+ { unsigned ml;
+ for (ml=0; ml<=MaxML; ml++)
+ optPtr->matchLengthFreq[ml] = 1;
+ }
+ optPtr->matchLengthSum = MaxML+1;
+
+ { unsigned const baseOFCfreqs[MaxOff+1] = {
+ 6, 2, 1, 1, 2, 3, 4, 4,
+ 4, 3, 2, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1
+ };
+ ZSTD_memcpy(optPtr->offCodeFreq, baseOFCfreqs, sizeof(baseOFCfreqs));
+ optPtr->offCodeSum = sum_u32(baseOFCfreqs, MaxOff+1);
+ }
+
+ }
+
+ } else { /* new block : scale down accumulated statistics */
+
+ if (compressedLiterals)
+ optPtr->litSum = ZSTD_scaleStats(optPtr->litFreq, MaxLit, 12);
+ optPtr->litLengthSum = ZSTD_scaleStats(optPtr->litLengthFreq, MaxLL, 11);
+ optPtr->matchLengthSum = ZSTD_scaleStats(optPtr->matchLengthFreq, MaxML, 11);
+ optPtr->offCodeSum = ZSTD_scaleStats(optPtr->offCodeFreq, MaxOff, 11);
+ }
+
+ ZSTD_setBasePrices(optPtr, optLevel);
+}
+
+/* ZSTD_rawLiteralsCost() :
+ * price of literals (only) in specified segment (which length can be 0).
+ * does not include price of literalLength symbol */
+static U32 ZSTD_rawLiteralsCost(const BYTE* const literals, U32 const litLength,
+ const optState_t* const optPtr,
+ int optLevel)
+{
+ if (litLength == 0) return 0;
+
+ if (!ZSTD_compressedLiterals(optPtr))
+ return (litLength << 3) * BITCOST_MULTIPLIER; /* Uncompressed - 8 bytes per literal. */
+
+ if (optPtr->priceType == zop_predef)
+ return (litLength*6) * BITCOST_MULTIPLIER; /* 6 bit per literal - no statistic used */
+
+ /* dynamic statistics */
+ { U32 price = optPtr->litSumBasePrice * litLength;
+ U32 const litPriceMax = optPtr->litSumBasePrice - BITCOST_MULTIPLIER;
+ U32 u;
+ assert(optPtr->litSumBasePrice >= BITCOST_MULTIPLIER);
+ for (u=0; u < litLength; u++) {
+ U32 litPrice = WEIGHT(optPtr->litFreq[literals[u]], optLevel);
+ if (UNLIKELY(litPrice > litPriceMax)) litPrice = litPriceMax;
+ price -= litPrice;
+ }
+ return price;
+ }
+}
+
+/* ZSTD_litLengthPrice() :
+ * cost of literalLength symbol */
+static U32 ZSTD_litLengthPrice(U32 const litLength, const optState_t* const optPtr, int optLevel)
+{
+ assert(litLength <= ZSTD_BLOCKSIZE_MAX);
+ if (optPtr->priceType == zop_predef)
+ return WEIGHT(litLength, optLevel);
+
+ /* ZSTD_LLcode() can't compute litLength price for sizes >= ZSTD_BLOCKSIZE_MAX
+ * because it isn't representable in the zstd format.
+ * So instead just pretend it would cost 1 bit more than ZSTD_BLOCKSIZE_MAX - 1.
+ * In such a case, the block would be all literals.
+ */
+ if (litLength == ZSTD_BLOCKSIZE_MAX)
+ return BITCOST_MULTIPLIER + ZSTD_litLengthPrice(ZSTD_BLOCKSIZE_MAX - 1, optPtr, optLevel);
+
+ /* dynamic statistics */
+ { U32 const llCode = ZSTD_LLcode(litLength);
+ return (LL_bits[llCode] * BITCOST_MULTIPLIER)
+ + optPtr->litLengthSumBasePrice
+ - WEIGHT(optPtr->litLengthFreq[llCode], optLevel);
+ }
+}
+
+/* ZSTD_getMatchPrice() :
+ * Provides the cost of the match part (offset + matchLength) of a sequence.
+ * Must be combined with ZSTD_fullLiteralsCost() to get the full cost of a sequence.
+ * @offBase : sumtype, representing an offset or a repcode, and using numeric representation of ZSTD_storeSeq()
+ * @optLevel: when <2, favors small offset for decompression speed (improved cache efficiency)
+ */
+FORCE_INLINE_TEMPLATE U32
+ZSTD_getMatchPrice(U32 const offBase,
+ U32 const matchLength,
+ const optState_t* const optPtr,
+ int const optLevel)
+{
+ U32 price;
+ U32 const offCode = ZSTD_highbit32(offBase);
+ U32 const mlBase = matchLength - MINMATCH;
+ assert(matchLength >= MINMATCH);
+
+ if (optPtr->priceType == zop_predef) /* fixed scheme, does not use statistics */
+ return WEIGHT(mlBase, optLevel)
+ + ((16 + offCode) * BITCOST_MULTIPLIER); /* emulated offset cost */
+
+ /* dynamic statistics */
+ price = (offCode * BITCOST_MULTIPLIER) + (optPtr->offCodeSumBasePrice - WEIGHT(optPtr->offCodeFreq[offCode], optLevel));
+ if ((optLevel<2) /*static*/ && offCode >= 20)
+ price += (offCode-19)*2 * BITCOST_MULTIPLIER; /* handicap for long distance offsets, favor decompression speed */
+
+ /* match Length */
+ { U32 const mlCode = ZSTD_MLcode(mlBase);
+ price += (ML_bits[mlCode] * BITCOST_MULTIPLIER) + (optPtr->matchLengthSumBasePrice - WEIGHT(optPtr->matchLengthFreq[mlCode], optLevel));
+ }
+
+ price += BITCOST_MULTIPLIER / 5; /* heuristic : make matches a bit more costly to favor less sequences -> faster decompression speed */
+
+ DEBUGLOG(8, "ZSTD_getMatchPrice(ml:%u) = %u", matchLength, price);
+ return price;
+}
+
+/* ZSTD_updateStats() :
+ * assumption : literals + litLength <= iend */
+static void ZSTD_updateStats(optState_t* const optPtr,
+ U32 litLength, const BYTE* literals,
+ U32 offBase, U32 matchLength)
+{
+ /* literals */
+ if (ZSTD_compressedLiterals(optPtr)) {
+ U32 u;
+ for (u=0; u < litLength; u++)
+ optPtr->litFreq[literals[u]] += ZSTD_LITFREQ_ADD;
+ optPtr->litSum += litLength*ZSTD_LITFREQ_ADD;
+ }
+
+ /* literal Length */
+ { U32 const llCode = ZSTD_LLcode(litLength);
+ optPtr->litLengthFreq[llCode]++;
+ optPtr->litLengthSum++;
+ }
+
+ /* offset code : follows storeSeq() numeric representation */
+ { U32 const offCode = ZSTD_highbit32(offBase);
+ assert(offCode <= MaxOff);
+ optPtr->offCodeFreq[offCode]++;
+ optPtr->offCodeSum++;
+ }
+
+ /* match Length */
+ { U32 const mlBase = matchLength - MINMATCH;
+ U32 const mlCode = ZSTD_MLcode(mlBase);
+ optPtr->matchLengthFreq[mlCode]++;
+ optPtr->matchLengthSum++;
+ }
+}
+
+
+/* ZSTD_readMINMATCH() :
+ * function safe only for comparisons
+ * assumption : memPtr must be at least 4 bytes before end of buffer */
+MEM_STATIC U32 ZSTD_readMINMATCH(const void* memPtr, U32 length)
+{
+ switch (length)
+ {
+ default :
+ case 4 : return MEM_read32(memPtr);
+ case 3 : if (MEM_isLittleEndian())
+ return MEM_read32(memPtr)<<8;
+ else
+ return MEM_read32(memPtr)>>8;
+ }
+}
+
+
+/* Update hashTable3 up to ip (excluded)
+ Assumption : always within prefix (i.e. not within extDict) */
+static U32 ZSTD_insertAndFindFirstIndexHash3 (const ZSTD_matchState_t* ms,
+ U32* nextToUpdate3,
+ const BYTE* const ip)
+{
+ U32* const hashTable3 = ms->hashTable3;
+ U32 const hashLog3 = ms->hashLog3;
+ const BYTE* const base = ms->window.base;
+ U32 idx = *nextToUpdate3;
+ U32 const target = (U32)(ip - base);
+ size_t const hash3 = ZSTD_hash3Ptr(ip, hashLog3);
+ assert(hashLog3 > 0);
+
+ while(idx < target) {
+ hashTable3[ZSTD_hash3Ptr(base+idx, hashLog3)] = idx;
+ idx++;
+ }
+
+ *nextToUpdate3 = target;
+ return hashTable3[hash3];
+}
+
+
+/*-*************************************
+* Binary Tree search
+***************************************/
+/** ZSTD_insertBt1() : add one or multiple positions to tree.
+ * @param ip assumed <= iend-8 .
+ * @param target The target of ZSTD_updateTree_internal() - we are filling to this position
+ * @return : nb of positions added */
+static U32 ZSTD_insertBt1(
+ const ZSTD_matchState_t* ms,
+ const BYTE* const ip, const BYTE* const iend,
+ U32 const target,
+ U32 const mls, const int extDict)
+{
+ const ZSTD_compressionParameters* const cParams = &ms->cParams;
+ U32* const hashTable = ms->hashTable;
+ U32 const hashLog = cParams->hashLog;
+ size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
+ U32* const bt = ms->chainTable;
+ U32 const btLog = cParams->chainLog - 1;
+ U32 const btMask = (1 << btLog) - 1;
+ U32 matchIndex = hashTable[h];
+ size_t commonLengthSmaller=0, commonLengthLarger=0;
+ const BYTE* const base = ms->window.base;
+ const BYTE* const dictBase = ms->window.dictBase;
+ const U32 dictLimit = ms->window.dictLimit;
+ const BYTE* const dictEnd = dictBase + dictLimit;
+ const BYTE* const prefixStart = base + dictLimit;
+ const BYTE* match;
+ const U32 curr = (U32)(ip-base);
+ const U32 btLow = btMask >= curr ? 0 : curr - btMask;
+ U32* smallerPtr = bt + 2*(curr&btMask);
+ U32* largerPtr = smallerPtr + 1;
+ U32 dummy32; /* to be nullified at the end */
+ /* windowLow is based on target because
+ * we only need positions that will be in the window at the end of the tree update.
+ */
+ U32 const windowLow = ZSTD_getLowestMatchIndex(ms, target, cParams->windowLog);
+ U32 matchEndIdx = curr+8+1;
+ size_t bestLength = 8;
+ U32 nbCompares = 1U << cParams->searchLog;
+#ifdef ZSTD_C_PREDICT
+ U32 predictedSmall = *(bt + 2*((curr-1)&btMask) + 0);
+ U32 predictedLarge = *(bt + 2*((curr-1)&btMask) + 1);
+ predictedSmall += (predictedSmall>0);
+ predictedLarge += (predictedLarge>0);
+#endif /* ZSTD_C_PREDICT */
+
+ DEBUGLOG(8, "ZSTD_insertBt1 (%u)", curr);
+
+ assert(curr <= target);
+ assert(ip <= iend-8); /* required for h calculation */
+ hashTable[h] = curr; /* Update Hash Table */
+
+ assert(windowLow > 0);
+ for (; nbCompares && (matchIndex >= windowLow); --nbCompares) {
+ U32* const nextPtr = bt + 2*(matchIndex & btMask);
+ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
+ assert(matchIndex < curr);
+
+#ifdef ZSTD_C_PREDICT /* note : can create issues when hlog small <= 11 */
+ const U32* predictPtr = bt + 2*((matchIndex-1) & btMask); /* written this way, as bt is a roll buffer */
+ if (matchIndex == predictedSmall) {
+ /* no need to check length, result known */
+ *smallerPtr = matchIndex;
+ 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) */
+ predictedSmall = predictPtr[1] + (predictPtr[1]>0);
+ continue;
+ }
+ if (matchIndex == predictedLarge) {
+ *largerPtr = matchIndex;
+ if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop the search */
+ largerPtr = nextPtr;
+ matchIndex = nextPtr[0];
+ predictedLarge = predictPtr[0] + (predictPtr[0]>0);
+ continue;
+ }
+#endif
+
+ if (!extDict || (matchIndex+matchLength >= dictLimit)) {
+ assert(matchIndex+matchLength >= dictLimit); /* might be wrong if actually extDict */
+ match = base + matchIndex;
+ matchLength += ZSTD_count(ip+matchLength, match+matchLength, iend);
+ } else {
+ match = dictBase + matchIndex;
+ matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iend, dictEnd, prefixStart);
+ if (matchIndex+matchLength >= dictLimit)
+ match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
+ }
+
+ if (matchLength > bestLength) {
+ bestLength = matchLength;
+ if (matchLength > matchEndIdx - matchIndex)
+ matchEndIdx = matchIndex + (U32)matchLength;
+ }
+
+ if (ip+matchLength == iend) { /* equal : no way to know if inf or sup */
+ break; /* drop , to guarantee consistency ; miss a bit of compression, but other solutions can corrupt tree */
+ }
+
+ if (match[matchLength] < ip[matchLength]) { /* necessarily within buffer */
+ /* match is smaller than current */
+ *smallerPtr = matchIndex; /* update smaller idx */
+ commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
+ if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop searching */
+ smallerPtr = nextPtr+1; /* new "candidate" => larger than match, which was smaller than target */
+ matchIndex = nextPtr[1]; /* new matchIndex, larger than previous and closer to current */
+ } else {
+ /* match is larger than current */
+ *largerPtr = matchIndex;
+ commonLengthLarger = matchLength;
+ if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop searching */
+ largerPtr = nextPtr;
+ matchIndex = nextPtr[0];
+ } }
+
+ *smallerPtr = *largerPtr = 0;
+ { U32 positions = 0;
+ if (bestLength > 384) positions = MIN(192, (U32)(bestLength - 384)); /* speed optimization */
+ assert(matchEndIdx > curr + 8);
+ return MAX(positions, matchEndIdx - (curr + 8));
+ }
+}
+
+FORCE_INLINE_TEMPLATE
+void ZSTD_updateTree_internal(
+ ZSTD_matchState_t* ms,
+ const BYTE* const ip, const BYTE* const iend,
+ const U32 mls, const ZSTD_dictMode_e dictMode)
+{
+ const BYTE* const base = ms->window.base;
+ U32 const target = (U32)(ip - base);
+ U32 idx = ms->nextToUpdate;
+ DEBUGLOG(6, "ZSTD_updateTree_internal, from %u to %u (dictMode:%u)",
+ idx, target, dictMode);
+
+ while(idx < target) {
+ U32 const forward = ZSTD_insertBt1(ms, base+idx, iend, target, mls, dictMode == ZSTD_extDict);
+ assert(idx < (U32)(idx + forward));
+ idx += forward;
+ }
+ assert((size_t)(ip - base) <= (size_t)(U32)(-1));
+ assert((size_t)(iend - base) <= (size_t)(U32)(-1));
+ ms->nextToUpdate = target;
+}
+
+void ZSTD_updateTree(ZSTD_matchState_t* ms, const BYTE* ip, const BYTE* iend) {
+ ZSTD_updateTree_internal(ms, ip, iend, ms->cParams.minMatch, ZSTD_noDict);
+}
+
+FORCE_INLINE_TEMPLATE U32
+ZSTD_insertBtAndGetAllMatches (
+ ZSTD_match_t* matches, /* store result (found matches) in this table (presumed large enough) */
+ ZSTD_matchState_t* ms,
+ U32* nextToUpdate3,
+ const BYTE* const ip, const BYTE* const iLimit,
+ const ZSTD_dictMode_e dictMode,
+ const U32 rep[ZSTD_REP_NUM],
+ const U32 ll0, /* tells if associated literal length is 0 or not. This value must be 0 or 1 */
+ const U32 lengthToBeat,
+ const U32 mls /* template */)
+{
+ const ZSTD_compressionParameters* const cParams = &ms->cParams;
+ U32 const sufficient_len = MIN(cParams->targetLength, ZSTD_OPT_NUM -1);
+ const BYTE* const base = ms->window.base;
+ U32 const curr = (U32)(ip-base);
+ U32 const hashLog = cParams->hashLog;
+ U32 const minMatch = (mls==3) ? 3 : 4;
+ U32* const hashTable = ms->hashTable;
+ size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
+ U32 matchIndex = hashTable[h];
+ U32* const bt = ms->chainTable;
+ U32 const btLog = cParams->chainLog - 1;
+ U32 const btMask= (1U << btLog) - 1;
+ size_t commonLengthSmaller=0, commonLengthLarger=0;
+ const BYTE* const dictBase = ms->window.dictBase;
+ U32 const dictLimit = ms->window.dictLimit;
+ const BYTE* const dictEnd = dictBase + dictLimit;
+ const BYTE* const prefixStart = base + dictLimit;
+ U32 const btLow = (btMask >= curr) ? 0 : curr - btMask;
+ U32 const windowLow = ZSTD_getLowestMatchIndex(ms, curr, cParams->windowLog);
+ U32 const matchLow = windowLow ? windowLow : 1;
+ U32* smallerPtr = bt + 2*(curr&btMask);
+ U32* largerPtr = bt + 2*(curr&btMask) + 1;
+ U32 matchEndIdx = curr+8+1; /* farthest referenced position of any match => detects repetitive patterns */
+ U32 dummy32; /* to be nullified at the end */
+ U32 mnum = 0;
+ U32 nbCompares = 1U << cParams->searchLog;
+
+ const ZSTD_matchState_t* dms = dictMode == ZSTD_dictMatchState ? ms->dictMatchState : NULL;
+ const ZSTD_compressionParameters* const dmsCParams =
+ dictMode == ZSTD_dictMatchState ? &dms->cParams : NULL;
+ const BYTE* const dmsBase = dictMode == ZSTD_dictMatchState ? dms->window.base : NULL;
+ const BYTE* const dmsEnd = dictMode == ZSTD_dictMatchState ? dms->window.nextSrc : NULL;
+ U32 const dmsHighLimit = dictMode == ZSTD_dictMatchState ? (U32)(dmsEnd - dmsBase) : 0;
+ U32 const dmsLowLimit = dictMode == ZSTD_dictMatchState ? dms->window.lowLimit : 0;
+ U32 const dmsIndexDelta = dictMode == ZSTD_dictMatchState ? windowLow - dmsHighLimit : 0;
+ U32 const dmsHashLog = dictMode == ZSTD_dictMatchState ? dmsCParams->hashLog : hashLog;
+ U32 const dmsBtLog = dictMode == ZSTD_dictMatchState ? dmsCParams->chainLog - 1 : btLog;
+ U32 const dmsBtMask = dictMode == ZSTD_dictMatchState ? (1U << dmsBtLog) - 1 : 0;
+ U32 const dmsBtLow = dictMode == ZSTD_dictMatchState && dmsBtMask < dmsHighLimit - dmsLowLimit ? dmsHighLimit - dmsBtMask : dmsLowLimit;
+
+ size_t bestLength = lengthToBeat-1;
+ DEBUGLOG(8, "ZSTD_insertBtAndGetAllMatches: current=%u", curr);
+
+ /* check repCode */
+ assert(ll0 <= 1); /* necessarily 1 or 0 */
+ { U32 const lastR = ZSTD_REP_NUM + ll0;
+ U32 repCode;
+ for (repCode = ll0; repCode < lastR; repCode++) {
+ U32 const repOffset = (repCode==ZSTD_REP_NUM) ? (rep[0] - 1) : rep[repCode];
+ U32 const repIndex = curr - repOffset;
+ U32 repLen = 0;
+ assert(curr >= dictLimit);
+ if (repOffset-1 /* intentional overflow, discards 0 and -1 */ < curr-dictLimit) { /* equivalent to `curr > repIndex >= dictLimit` */
+ /* We must validate the repcode offset because when we're using a dictionary the
+ * valid offset range shrinks when the dictionary goes out of bounds.
+ */
+ if ((repIndex >= windowLow) & (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repOffset, minMatch))) {
+ repLen = (U32)ZSTD_count(ip+minMatch, ip+minMatch-repOffset, iLimit) + minMatch;
+ }
+ } else { /* repIndex < dictLimit || repIndex >= curr */
+ const BYTE* const repMatch = dictMode == ZSTD_dictMatchState ?
+ dmsBase + repIndex - dmsIndexDelta :
+ dictBase + repIndex;
+ assert(curr >= windowLow);
+ if ( dictMode == ZSTD_extDict
+ && ( ((repOffset-1) /*intentional overflow*/ < curr - windowLow) /* equivalent to `curr > repIndex >= windowLow` */
+ & (((U32)((dictLimit-1) - repIndex) >= 3) ) /* intentional overflow : do not test positions overlapping 2 memory segments */)
+ && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch)) ) {
+ repLen = (U32)ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iLimit, dictEnd, prefixStart) + minMatch;
+ }
+ if (dictMode == ZSTD_dictMatchState
+ && ( ((repOffset-1) /*intentional overflow*/ < curr - (dmsLowLimit + dmsIndexDelta)) /* equivalent to `curr > repIndex >= dmsLowLimit` */
+ & ((U32)((dictLimit-1) - repIndex) >= 3) ) /* intentional overflow : do not test positions overlapping 2 memory segments */
+ && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch)) ) {
+ repLen = (U32)ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iLimit, dmsEnd, prefixStart) + minMatch;
+ } }
+ /* save longer solution */
+ if (repLen > bestLength) {
+ DEBUGLOG(8, "found repCode %u (ll0:%u, offset:%u) of length %u",
+ repCode, ll0, repOffset, repLen);
+ bestLength = repLen;
+ matches[mnum].off = REPCODE_TO_OFFBASE(repCode - ll0 + 1); /* expect value between 1 and 3 */
+ matches[mnum].len = (U32)repLen;
+ mnum++;
+ if ( (repLen > sufficient_len)
+ | (ip+repLen == iLimit) ) { /* best possible */
+ return mnum;
+ } } } }
+
+ /* HC3 match finder */
+ if ((mls == 3) /*static*/ && (bestLength < mls)) {
+ U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3(ms, nextToUpdate3, ip);
+ if ((matchIndex3 >= matchLow)
+ & (curr - matchIndex3 < (1<<18)) /*heuristic : longer distance likely too expensive*/ ) {
+ size_t mlen;
+ if ((dictMode == ZSTD_noDict) /*static*/ || (dictMode == ZSTD_dictMatchState) /*static*/ || (matchIndex3 >= dictLimit)) {
+ const BYTE* const match = base + matchIndex3;
+ mlen = ZSTD_count(ip, match, iLimit);
+ } else {
+ const BYTE* const match = dictBase + matchIndex3;
+ mlen = ZSTD_count_2segments(ip, match, iLimit, dictEnd, prefixStart);
+ }
+
+ /* save best solution */
+ if (mlen >= mls /* == 3 > bestLength */) {
+ DEBUGLOG(8, "found small match with hlog3, of length %u",
+ (U32)mlen);
+ bestLength = mlen;
+ assert(curr > matchIndex3);
+ assert(mnum==0); /* no prior solution */
+ matches[0].off = OFFSET_TO_OFFBASE(curr - matchIndex3);
+ matches[0].len = (U32)mlen;
+ mnum = 1;
+ if ( (mlen > sufficient_len) |
+ (ip+mlen == iLimit) ) { /* best possible length */
+ ms->nextToUpdate = curr+1; /* skip insertion */
+ return 1;
+ } } }
+ /* no dictMatchState lookup: dicts don't have a populated HC3 table */
+ } /* if (mls == 3) */
+
+ hashTable[h] = curr; /* Update Hash Table */
+
+ for (; nbCompares && (matchIndex >= matchLow); --nbCompares) {
+ U32* const nextPtr = bt + 2*(matchIndex & btMask);
+ const BYTE* match;
+ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
+ assert(curr > matchIndex);
+
+ if ((dictMode == ZSTD_noDict) || (dictMode == ZSTD_dictMatchState) || (matchIndex+matchLength >= dictLimit)) {
+ assert(matchIndex+matchLength >= dictLimit); /* ensure the condition is correct when !extDict */
+ match = base + matchIndex;
+ if (matchIndex >= dictLimit) assert(memcmp(match, ip, matchLength) == 0); /* ensure early section of match is equal as expected */
+ matchLength += ZSTD_count(ip+matchLength, match+matchLength, iLimit);
+ } else {
+ match = dictBase + matchIndex;
+ assert(memcmp(match, ip, matchLength) == 0); /* ensure early section of match is equal as expected */
+ matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iLimit, dictEnd, prefixStart);
+ if (matchIndex+matchLength >= dictLimit)
+ match = base + matchIndex; /* prepare for match[matchLength] read */
+ }
+
+ if (matchLength > bestLength) {
+ DEBUGLOG(8, "found match of length %u at distance %u (offBase=%u)",
+ (U32)matchLength, curr - matchIndex, OFFSET_TO_OFFBASE(curr - matchIndex));
+ assert(matchEndIdx > matchIndex);
+ if (matchLength > matchEndIdx - matchIndex)
+ matchEndIdx = matchIndex + (U32)matchLength;
+ bestLength = matchLength;
+ matches[mnum].off = OFFSET_TO_OFFBASE(curr - matchIndex);
+ matches[mnum].len = (U32)matchLength;
+ mnum++;
+ if ( (matchLength > ZSTD_OPT_NUM)
+ | (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */) {
+ if (dictMode == ZSTD_dictMatchState) nbCompares = 0; /* break should also skip searching dms */
+ break; /* drop, to preserve bt consistency (miss a little bit of compression) */
+ } }
+
+ if (match[matchLength] < ip[matchLength]) {
+ /* match 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 candidate => larger than match, which was smaller than current */
+ matchIndex = nextPtr[1]; /* new matchIndex, larger than previous, closer to current */
+ } else {
+ *largerPtr = matchIndex;
+ commonLengthLarger = matchLength;
+ if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop the search */
+ largerPtr = nextPtr;
+ matchIndex = nextPtr[0];
+ } }
+
+ *smallerPtr = *largerPtr = 0;
+
+ assert(nbCompares <= (1U << ZSTD_SEARCHLOG_MAX)); /* Check we haven't underflowed. */
+ if (dictMode == ZSTD_dictMatchState && nbCompares) {
+ size_t const dmsH = ZSTD_hashPtr(ip, dmsHashLog, mls);
+ U32 dictMatchIndex = dms->hashTable[dmsH];
+ const U32* const dmsBt = dms->chainTable;
+ commonLengthSmaller = commonLengthLarger = 0;
+ for (; nbCompares && (dictMatchIndex > dmsLowLimit); --nbCompares) {
+ const U32* const nextPtr = dmsBt + 2*(dictMatchIndex & dmsBtMask);
+ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
+ const BYTE* match = dmsBase + dictMatchIndex;
+ matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iLimit, dmsEnd, prefixStart);
+ if (dictMatchIndex+matchLength >= dmsHighLimit)
+ match = base + dictMatchIndex + dmsIndexDelta; /* to prepare for next usage of match[matchLength] */
+
+ if (matchLength > bestLength) {
+ matchIndex = dictMatchIndex + dmsIndexDelta;
+ DEBUGLOG(8, "found dms match of length %u at distance %u (offBase=%u)",
+ (U32)matchLength, curr - matchIndex, OFFSET_TO_OFFBASE(curr - matchIndex));
+ if (matchLength > matchEndIdx - matchIndex)
+ matchEndIdx = matchIndex + (U32)matchLength;
+ bestLength = matchLength;
+ matches[mnum].off = OFFSET_TO_OFFBASE(curr - matchIndex);
+ matches[mnum].len = (U32)matchLength;
+ mnum++;
+ if ( (matchLength > ZSTD_OPT_NUM)
+ | (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */) {
+ break; /* drop, to guarantee consistency (miss a little bit of compression) */
+ } }
+
+ if (dictMatchIndex <= dmsBtLow) { break; } /* beyond tree size, stop the search */
+ if (match[matchLength] < ip[matchLength]) {
+ commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
+ dictMatchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to current) */
+ } else {
+ /* match is larger than current */
+ commonLengthLarger = matchLength;
+ dictMatchIndex = nextPtr[0];
+ } } } /* if (dictMode == ZSTD_dictMatchState) */
+
+ assert(matchEndIdx > curr+8);
+ ms->nextToUpdate = matchEndIdx - 8; /* skip repetitive patterns */
+ return mnum;
+}
+
+typedef U32 (*ZSTD_getAllMatchesFn)(
+ ZSTD_match_t*,
+ ZSTD_matchState_t*,
+ U32*,
+ const BYTE*,
+ const BYTE*,
+ const U32 rep[ZSTD_REP_NUM],
+ U32 const ll0,
+ U32 const lengthToBeat);
+
+FORCE_INLINE_TEMPLATE U32 ZSTD_btGetAllMatches_internal(
+ ZSTD_match_t* matches,
+ ZSTD_matchState_t* ms,
+ U32* nextToUpdate3,
+ const BYTE* ip,
+ const BYTE* const iHighLimit,
+ const U32 rep[ZSTD_REP_NUM],
+ U32 const ll0,
+ U32 const lengthToBeat,
+ const ZSTD_dictMode_e dictMode,
+ const U32 mls)
+{
+ assert(BOUNDED(3, ms->cParams.minMatch, 6) == mls);
+ DEBUGLOG(8, "ZSTD_BtGetAllMatches(dictMode=%d, mls=%u)", (int)dictMode, mls);
+ if (ip < ms->window.base + ms->nextToUpdate)
+ return 0; /* skipped area */
+ ZSTD_updateTree_internal(ms, ip, iHighLimit, mls, dictMode);
+ return ZSTD_insertBtAndGetAllMatches(matches, ms, nextToUpdate3, ip, iHighLimit, dictMode, rep, ll0, lengthToBeat, mls);
+}
+
+#define ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, mls) ZSTD_btGetAllMatches_##dictMode##_##mls
+
+#define GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, mls) \
+ static U32 ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, mls)( \
+ ZSTD_match_t* matches, \
+ ZSTD_matchState_t* ms, \
+ U32* nextToUpdate3, \
+ const BYTE* ip, \
+ const BYTE* const iHighLimit, \
+ const U32 rep[ZSTD_REP_NUM], \
+ U32 const ll0, \
+ U32 const lengthToBeat) \
+ { \
+ return ZSTD_btGetAllMatches_internal( \
+ matches, ms, nextToUpdate3, ip, iHighLimit, \
+ rep, ll0, lengthToBeat, ZSTD_##dictMode, mls); \
+ }
+
+#define GEN_ZSTD_BT_GET_ALL_MATCHES(dictMode) \
+ GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, 3) \
+ GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, 4) \
+ GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, 5) \
+ GEN_ZSTD_BT_GET_ALL_MATCHES_(dictMode, 6)
+
+GEN_ZSTD_BT_GET_ALL_MATCHES(noDict)
+GEN_ZSTD_BT_GET_ALL_MATCHES(extDict)
+GEN_ZSTD_BT_GET_ALL_MATCHES(dictMatchState)
+
+#define ZSTD_BT_GET_ALL_MATCHES_ARRAY(dictMode) \
+ { \
+ ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, 3), \
+ ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, 4), \
+ ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, 5), \
+ ZSTD_BT_GET_ALL_MATCHES_FN(dictMode, 6) \
+ }
+
+static ZSTD_getAllMatchesFn
+ZSTD_selectBtGetAllMatches(ZSTD_matchState_t const* ms, ZSTD_dictMode_e const dictMode)
+{
+ ZSTD_getAllMatchesFn const getAllMatchesFns[3][4] = {
+ ZSTD_BT_GET_ALL_MATCHES_ARRAY(noDict),
+ ZSTD_BT_GET_ALL_MATCHES_ARRAY(extDict),
+ ZSTD_BT_GET_ALL_MATCHES_ARRAY(dictMatchState)
+ };
+ U32 const mls = BOUNDED(3, ms->cParams.minMatch, 6);
+ assert((U32)dictMode < 3);
+ assert(mls - 3 < 4);
+ return getAllMatchesFns[(int)dictMode][mls - 3];
+}
+
+/*************************
+* LDM helper functions *
+*************************/
+
+/* Struct containing info needed to make decision about ldm inclusion */
+typedef struct {
+ rawSeqStore_t seqStore; /* External match candidates store for this block */
+ U32 startPosInBlock; /* Start position of the current match candidate */
+ U32 endPosInBlock; /* End position of the current match candidate */
+ U32 offset; /* Offset of the match candidate */
+} ZSTD_optLdm_t;
+
+/* ZSTD_optLdm_skipRawSeqStoreBytes():
+ * Moves forward in @rawSeqStore by @nbBytes,
+ * which will update the fields 'pos' and 'posInSequence'.
+ */
+static void ZSTD_optLdm_skipRawSeqStoreBytes(rawSeqStore_t* rawSeqStore, size_t nbBytes)
+{
+ U32 currPos = (U32)(rawSeqStore->posInSequence + nbBytes);
+ while (currPos && rawSeqStore->pos < rawSeqStore->size) {
+ rawSeq currSeq = rawSeqStore->seq[rawSeqStore->pos];
+ if (currPos >= currSeq.litLength + currSeq.matchLength) {
+ currPos -= currSeq.litLength + currSeq.matchLength;
+ rawSeqStore->pos++;
+ } else {
+ rawSeqStore->posInSequence = currPos;
+ break;
+ }
+ }
+ if (currPos == 0 || rawSeqStore->pos == rawSeqStore->size) {
+ rawSeqStore->posInSequence = 0;
+ }
+}
+
+/* ZSTD_opt_getNextMatchAndUpdateSeqStore():
+ * Calculates the beginning and end of the next match in the current block.
+ * Updates 'pos' and 'posInSequence' of the ldmSeqStore.
+ */
+static void
+ZSTD_opt_getNextMatchAndUpdateSeqStore(ZSTD_optLdm_t* optLdm, U32 currPosInBlock,
+ U32 blockBytesRemaining)
+{
+ rawSeq currSeq;
+ U32 currBlockEndPos;
+ U32 literalsBytesRemaining;
+ U32 matchBytesRemaining;
+
+ /* Setting match end position to MAX to ensure we never use an LDM during this block */
+ if (optLdm->seqStore.size == 0 || optLdm->seqStore.pos >= optLdm->seqStore.size) {
+ optLdm->startPosInBlock = UINT_MAX;
+ optLdm->endPosInBlock = UINT_MAX;
+ return;
+ }
+ /* Calculate appropriate bytes left in matchLength and litLength
+ * after adjusting based on ldmSeqStore->posInSequence */
+ currSeq = optLdm->seqStore.seq[optLdm->seqStore.pos];
+ assert(optLdm->seqStore.posInSequence <= currSeq.litLength + currSeq.matchLength);
+ currBlockEndPos = currPosInBlock + blockBytesRemaining;
+ literalsBytesRemaining = (optLdm->seqStore.posInSequence < currSeq.litLength) ?
+ currSeq.litLength - (U32)optLdm->seqStore.posInSequence :
+ 0;
+ matchBytesRemaining = (literalsBytesRemaining == 0) ?
+ currSeq.matchLength - ((U32)optLdm->seqStore.posInSequence - currSeq.litLength) :
+ currSeq.matchLength;
+
+ /* If there are more literal bytes than bytes remaining in block, no ldm is possible */
+ if (literalsBytesRemaining >= blockBytesRemaining) {
+ optLdm->startPosInBlock = UINT_MAX;
+ optLdm->endPosInBlock = UINT_MAX;
+ ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, blockBytesRemaining);
+ return;
+ }
+
+ /* Matches may be < MINMATCH by this process. In that case, we will reject them
+ when we are deciding whether or not to add the ldm */
+ optLdm->startPosInBlock = currPosInBlock + literalsBytesRemaining;
+ optLdm->endPosInBlock = optLdm->startPosInBlock + matchBytesRemaining;
+ optLdm->offset = currSeq.offset;
+
+ if (optLdm->endPosInBlock > currBlockEndPos) {
+ /* Match ends after the block ends, we can't use the whole match */
+ optLdm->endPosInBlock = currBlockEndPos;
+ ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, currBlockEndPos - currPosInBlock);
+ } else {
+ /* Consume nb of bytes equal to size of sequence left */
+ ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, literalsBytesRemaining + matchBytesRemaining);
+ }
+}
+
+/* ZSTD_optLdm_maybeAddMatch():
+ * Adds a match if it's long enough,
+ * based on it's 'matchStartPosInBlock' and 'matchEndPosInBlock',
+ * into 'matches'. Maintains the correct ordering of 'matches'.
+ */
+static void ZSTD_optLdm_maybeAddMatch(ZSTD_match_t* matches, U32* nbMatches,
+ const ZSTD_optLdm_t* optLdm, U32 currPosInBlock)
+{
+ U32 const posDiff = currPosInBlock - optLdm->startPosInBlock;
+ /* Note: ZSTD_match_t actually contains offBase and matchLength (before subtracting MINMATCH) */
+ U32 const candidateMatchLength = optLdm->endPosInBlock - optLdm->startPosInBlock - posDiff;
+
+ /* Ensure that current block position is not outside of the match */
+ if (currPosInBlock < optLdm->startPosInBlock
+ || currPosInBlock >= optLdm->endPosInBlock
+ || candidateMatchLength < MINMATCH) {
+ return;
+ }
+
+ if (*nbMatches == 0 || ((candidateMatchLength > matches[*nbMatches-1].len) && *nbMatches < ZSTD_OPT_NUM)) {
+ U32 const candidateOffBase = OFFSET_TO_OFFBASE(optLdm->offset);
+ DEBUGLOG(6, "ZSTD_optLdm_maybeAddMatch(): Adding ldm candidate match (offBase: %u matchLength %u) at block position=%u",
+ candidateOffBase, candidateMatchLength, currPosInBlock);
+ matches[*nbMatches].len = candidateMatchLength;
+ matches[*nbMatches].off = candidateOffBase;
+ (*nbMatches)++;
+ }
+}
+
+/* ZSTD_optLdm_processMatchCandidate():
+ * Wrapper function to update ldm seq store and call ldm functions as necessary.
+ */
+static void
+ZSTD_optLdm_processMatchCandidate(ZSTD_optLdm_t* optLdm,
+ ZSTD_match_t* matches, U32* nbMatches,
+ U32 currPosInBlock, U32 remainingBytes)
+{
+ if (optLdm->seqStore.size == 0 || optLdm->seqStore.pos >= optLdm->seqStore.size) {
+ return;
+ }
+
+ if (currPosInBlock >= optLdm->endPosInBlock) {
+ if (currPosInBlock > optLdm->endPosInBlock) {
+ /* The position at which ZSTD_optLdm_processMatchCandidate() is called is not necessarily
+ * at the end of a match from the ldm seq store, and will often be some bytes
+ * over beyond matchEndPosInBlock. As such, we need to correct for these "overshoots"
+ */
+ U32 const posOvershoot = currPosInBlock - optLdm->endPosInBlock;
+ ZSTD_optLdm_skipRawSeqStoreBytes(&optLdm->seqStore, posOvershoot);
+ }
+ ZSTD_opt_getNextMatchAndUpdateSeqStore(optLdm, currPosInBlock, remainingBytes);
+ }
+ ZSTD_optLdm_maybeAddMatch(matches, nbMatches, optLdm, currPosInBlock);
+}
+
+
+/*-*******************************
+* Optimal parser
+*********************************/
+
+static U32 ZSTD_totalLen(ZSTD_optimal_t sol)
+{
+ return sol.litlen + sol.mlen;
+}
+
+#if 0 /* debug */
+
+static void
+listStats(const U32* table, int lastEltID)
+{
+ int const nbElts = lastEltID + 1;
+ int enb;
+ for (enb=0; enb < nbElts; enb++) {
+ (void)table;
+ /* RAWLOG(2, "%3i:%3i, ", enb, table[enb]); */
+ RAWLOG(2, "%4i,", table[enb]);
+ }
+ RAWLOG(2, " \n");
+}
+
+#endif
+
+FORCE_INLINE_TEMPLATE size_t
+ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms,
+ seqStore_t* seqStore,
+ U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize,
+ const int optLevel,
+ const ZSTD_dictMode_e dictMode)
+{
+ optState_t* const optStatePtr = &ms->opt;
+ const BYTE* const istart = (const BYTE*)src;
+ const BYTE* ip = istart;
+ const BYTE* anchor = istart;
+ const BYTE* const iend = istart + srcSize;
+ const BYTE* const ilimit = iend - 8;
+ const BYTE* const base = ms->window.base;
+ const BYTE* const prefixStart = base + ms->window.dictLimit;
+ const ZSTD_compressionParameters* const cParams = &ms->cParams;
+
+ ZSTD_getAllMatchesFn getAllMatches = ZSTD_selectBtGetAllMatches(ms, dictMode);
+
+ U32 const sufficient_len = MIN(cParams->targetLength, ZSTD_OPT_NUM -1);
+ U32 const minMatch = (cParams->minMatch == 3) ? 3 : 4;
+ U32 nextToUpdate3 = ms->nextToUpdate;
+
+ ZSTD_optimal_t* const opt = optStatePtr->priceTable;
+ ZSTD_match_t* const matches = optStatePtr->matchTable;
+ ZSTD_optimal_t lastSequence;
+ ZSTD_optLdm_t optLdm;
+
+ ZSTD_memset(&lastSequence, 0, sizeof(ZSTD_optimal_t));
+
+ optLdm.seqStore = ms->ldmSeqStore ? *ms->ldmSeqStore : kNullRawSeqStore;
+ optLdm.endPosInBlock = optLdm.startPosInBlock = optLdm.offset = 0;
+ ZSTD_opt_getNextMatchAndUpdateSeqStore(&optLdm, (U32)(ip-istart), (U32)(iend-ip));
+
+ /* init */
+ DEBUGLOG(5, "ZSTD_compressBlock_opt_generic: current=%u, prefix=%u, nextToUpdate=%u",
+ (U32)(ip - base), ms->window.dictLimit, ms->nextToUpdate);
+ assert(optLevel <= 2);
+ ZSTD_rescaleFreqs(optStatePtr, (const BYTE*)src, srcSize, optLevel);
+ ip += (ip==prefixStart);
+
+ /* Match Loop */
+ while (ip < ilimit) {
+ U32 cur, last_pos = 0;
+
+ /* find first match */
+ { U32 const litlen = (U32)(ip - anchor);
+ U32 const ll0 = !litlen;
+ U32 nbMatches = getAllMatches(matches, ms, &nextToUpdate3, ip, iend, rep, ll0, minMatch);
+ ZSTD_optLdm_processMatchCandidate(&optLdm, matches, &nbMatches,
+ (U32)(ip-istart), (U32)(iend - ip));
+ if (!nbMatches) { ip++; continue; }
+
+ /* initialize opt[0] */
+ { U32 i ; for (i=0; i<ZSTD_REP_NUM; i++) opt[0].rep[i] = rep[i]; }
+ opt[0].mlen = 0; /* means is_a_literal */
+ opt[0].litlen = litlen;
+ /* We don't need to include the actual price of the literals because
+ * it is static for the duration of the forward pass, and is included
+ * in every price. We include the literal length to avoid negative
+ * prices when we subtract the previous literal length.
+ */
+ opt[0].price = (int)ZSTD_litLengthPrice(litlen, optStatePtr, optLevel);
+
+ /* large match -> immediate encoding */
+ { U32 const maxML = matches[nbMatches-1].len;
+ U32 const maxOffBase = matches[nbMatches-1].off;
+ DEBUGLOG(6, "found %u matches of maxLength=%u and maxOffBase=%u at cPos=%u => start new series",
+ nbMatches, maxML, maxOffBase, (U32)(ip-prefixStart));
+
+ if (maxML > sufficient_len) {
+ lastSequence.litlen = litlen;
+ lastSequence.mlen = maxML;
+ lastSequence.off = maxOffBase;
+ DEBUGLOG(6, "large match (%u>%u), immediate encoding",
+ maxML, sufficient_len);
+ cur = 0;
+ last_pos = ZSTD_totalLen(lastSequence);
+ goto _shortestPath;
+ } }
+
+ /* set prices for first matches starting position == 0 */
+ assert(opt[0].price >= 0);
+ { U32 const literalsPrice = (U32)opt[0].price + ZSTD_litLengthPrice(0, optStatePtr, optLevel);
+ U32 pos;
+ U32 matchNb;
+ for (pos = 1; pos < minMatch; pos++) {
+ opt[pos].price = ZSTD_MAX_PRICE; /* mlen, litlen and price will be fixed during forward scanning */
+ }
+ for (matchNb = 0; matchNb < nbMatches; matchNb++) {
+ U32 const offBase = matches[matchNb].off;
+ U32 const end = matches[matchNb].len;
+ for ( ; pos <= end ; pos++ ) {
+ U32 const matchPrice = ZSTD_getMatchPrice(offBase, pos, optStatePtr, optLevel);
+ U32 const sequencePrice = literalsPrice + matchPrice;
+ DEBUGLOG(7, "rPos:%u => set initial price : %.2f",
+ pos, ZSTD_fCost((int)sequencePrice));
+ opt[pos].mlen = pos;
+ opt[pos].off = offBase;
+ opt[pos].litlen = litlen;
+ opt[pos].price = (int)sequencePrice;
+ } }
+ last_pos = pos-1;
+ }
+ }
+
+ /* check further positions */
+ for (cur = 1; cur <= last_pos; cur++) {
+ const BYTE* const inr = ip + cur;
+ assert(cur < ZSTD_OPT_NUM);
+ DEBUGLOG(7, "cPos:%zi==rPos:%u", inr-istart, cur)
+
+ /* Fix current position with one literal if cheaper */
+ { U32 const litlen = (opt[cur-1].mlen == 0) ? opt[cur-1].litlen + 1 : 1;
+ int const price = opt[cur-1].price
+ + (int)ZSTD_rawLiteralsCost(ip+cur-1, 1, optStatePtr, optLevel)
+ + (int)ZSTD_litLengthPrice(litlen, optStatePtr, optLevel)
+ - (int)ZSTD_litLengthPrice(litlen-1, optStatePtr, optLevel);
+ assert(price < 1000000000); /* overflow check */
+ if (price <= opt[cur].price) {
+ DEBUGLOG(7, "cPos:%zi==rPos:%u : better price (%.2f<=%.2f) using literal (ll==%u) (hist:%u,%u,%u)",
+ inr-istart, cur, ZSTD_fCost(price), ZSTD_fCost(opt[cur].price), litlen,
+ opt[cur-1].rep[0], opt[cur-1].rep[1], opt[cur-1].rep[2]);
+ opt[cur].mlen = 0;
+ opt[cur].off = 0;
+ opt[cur].litlen = litlen;
+ opt[cur].price = price;
+ } else {
+ DEBUGLOG(7, "cPos:%zi==rPos:%u : literal would cost more (%.2f>%.2f) (hist:%u,%u,%u)",
+ inr-istart, cur, ZSTD_fCost(price), ZSTD_fCost(opt[cur].price),
+ opt[cur].rep[0], opt[cur].rep[1], opt[cur].rep[2]);
+ }
+ }
+
+ /* Set the repcodes of the current position. We must do it here
+ * because we rely on the repcodes of the 2nd to last sequence being
+ * correct to set the next chunks repcodes during the backward
+ * traversal.
+ */
+ ZSTD_STATIC_ASSERT(sizeof(opt[cur].rep) == sizeof(repcodes_t));
+ assert(cur >= opt[cur].mlen);
+ if (opt[cur].mlen != 0) {
+ U32 const prev = cur - opt[cur].mlen;
+ repcodes_t const newReps = ZSTD_newRep(opt[prev].rep, opt[cur].off, opt[cur].litlen==0);
+ ZSTD_memcpy(opt[cur].rep, &newReps, sizeof(repcodes_t));
+ } else {
+ ZSTD_memcpy(opt[cur].rep, opt[cur - 1].rep, sizeof(repcodes_t));
+ }
+
+ /* last match must start at a minimum distance of 8 from oend */
+ if (inr > ilimit) continue;
+
+ if (cur == last_pos) break;
+
+ if ( (optLevel==0) /*static_test*/
+ && (opt[cur+1].price <= opt[cur].price + (BITCOST_MULTIPLIER/2)) ) {
+ DEBUGLOG(7, "move to next rPos:%u : price is <=", cur+1);
+ continue; /* skip unpromising positions; about ~+6% speed, -0.01 ratio */
+ }
+
+ assert(opt[cur].price >= 0);
+ { U32 const ll0 = (opt[cur].mlen != 0);
+ U32 const litlen = (opt[cur].mlen == 0) ? opt[cur].litlen : 0;
+ U32 const previousPrice = (U32)opt[cur].price;
+ U32 const basePrice = previousPrice + ZSTD_litLengthPrice(0, optStatePtr, optLevel);
+ U32 nbMatches = getAllMatches(matches, ms, &nextToUpdate3, inr, iend, opt[cur].rep, ll0, minMatch);
+ U32 matchNb;
+
+ ZSTD_optLdm_processMatchCandidate(&optLdm, matches, &nbMatches,
+ (U32)(inr-istart), (U32)(iend-inr));
+
+ if (!nbMatches) {
+ DEBUGLOG(7, "rPos:%u : no match found", cur);
+ continue;
+ }
+
+ { U32 const maxML = matches[nbMatches-1].len;
+ DEBUGLOG(7, "cPos:%zi==rPos:%u, found %u matches, of maxLength=%u",
+ inr-istart, cur, nbMatches, maxML);
+
+ if ( (maxML > sufficient_len)
+ || (cur + maxML >= ZSTD_OPT_NUM) ) {
+ lastSequence.mlen = maxML;
+ lastSequence.off = matches[nbMatches-1].off;
+ lastSequence.litlen = litlen;
+ cur -= (opt[cur].mlen==0) ? opt[cur].litlen : 0; /* last sequence is actually only literals, fix cur to last match - note : may underflow, in which case, it's first sequence, and it's okay */
+ last_pos = cur + ZSTD_totalLen(lastSequence);
+ if (cur > ZSTD_OPT_NUM) cur = 0; /* underflow => first match */
+ goto _shortestPath;
+ } }
+
+ /* set prices using matches found at position == cur */
+ for (matchNb = 0; matchNb < nbMatches; matchNb++) {
+ U32 const offset = matches[matchNb].off;
+ U32 const lastML = matches[matchNb].len;
+ U32 const startML = (matchNb>0) ? matches[matchNb-1].len+1 : minMatch;
+ U32 mlen;
+
+ DEBUGLOG(7, "testing match %u => offBase=%4u, mlen=%2u, llen=%2u",
+ matchNb, matches[matchNb].off, lastML, litlen);
+
+ for (mlen = lastML; mlen >= startML; mlen--) { /* scan downward */
+ U32 const pos = cur + mlen;
+ int const price = (int)basePrice + (int)ZSTD_getMatchPrice(offset, mlen, optStatePtr, optLevel);
+
+ if ((pos > last_pos) || (price < opt[pos].price)) {
+ DEBUGLOG(7, "rPos:%u (ml=%2u) => new better price (%.2f<%.2f)",
+ pos, mlen, ZSTD_fCost(price), ZSTD_fCost(opt[pos].price));
+ while (last_pos < pos) { opt[last_pos+1].price = ZSTD_MAX_PRICE; last_pos++; } /* fill empty positions */
+ opt[pos].mlen = mlen;
+ opt[pos].off = offset;
+ opt[pos].litlen = litlen;
+ opt[pos].price = price;
+ } else {
+ DEBUGLOG(7, "rPos:%u (ml=%2u) => new price is worse (%.2f>=%.2f)",
+ pos, mlen, ZSTD_fCost(price), ZSTD_fCost(opt[pos].price));
+ if (optLevel==0) break; /* early update abort; gets ~+10% speed for about -0.01 ratio loss */
+ }
+ } } }
+ } /* for (cur = 1; cur <= last_pos; cur++) */
+
+ lastSequence = opt[last_pos];
+ cur = last_pos > ZSTD_totalLen(lastSequence) ? last_pos - ZSTD_totalLen(lastSequence) : 0; /* single sequence, and it starts before `ip` */
+ assert(cur < ZSTD_OPT_NUM); /* control overflow*/
+
+_shortestPath: /* cur, last_pos, best_mlen, best_off have to be set */
+ assert(opt[0].mlen == 0);
+
+ /* Set the next chunk's repcodes based on the repcodes of the beginning
+ * of the last match, and the last sequence. This avoids us having to
+ * update them while traversing the sequences.
+ */
+ if (lastSequence.mlen != 0) {
+ repcodes_t const reps = ZSTD_newRep(opt[cur].rep, lastSequence.off, lastSequence.litlen==0);
+ ZSTD_memcpy(rep, &reps, sizeof(reps));
+ } else {
+ ZSTD_memcpy(rep, opt[cur].rep, sizeof(repcodes_t));
+ }
+
+ { U32 const storeEnd = cur + 1;
+ U32 storeStart = storeEnd;
+ U32 seqPos = cur;
+
+ DEBUGLOG(6, "start reverse traversal (last_pos:%u, cur:%u)",
+ last_pos, cur); (void)last_pos;
+ assert(storeEnd < ZSTD_OPT_NUM);
+ DEBUGLOG(6, "last sequence copied into pos=%u (llen=%u,mlen=%u,ofc=%u)",
+ storeEnd, lastSequence.litlen, lastSequence.mlen, lastSequence.off);
+ opt[storeEnd] = lastSequence;
+ while (seqPos > 0) {
+ U32 const backDist = ZSTD_totalLen(opt[seqPos]);
+ storeStart--;
+ DEBUGLOG(6, "sequence from rPos=%u copied into pos=%u (llen=%u,mlen=%u,ofc=%u)",
+ seqPos, storeStart, opt[seqPos].litlen, opt[seqPos].mlen, opt[seqPos].off);
+ opt[storeStart] = opt[seqPos];
+ seqPos = (seqPos > backDist) ? seqPos - backDist : 0;
+ }
+
+ /* save sequences */
+ DEBUGLOG(6, "sending selected sequences into seqStore")
+ { U32 storePos;
+ for (storePos=storeStart; storePos <= storeEnd; storePos++) {
+ U32 const llen = opt[storePos].litlen;
+ U32 const mlen = opt[storePos].mlen;
+ U32 const offBase = opt[storePos].off;
+ U32 const advance = llen + mlen;
+ DEBUGLOG(6, "considering seq starting at %zi, llen=%u, mlen=%u",
+ anchor - istart, (unsigned)llen, (unsigned)mlen);
+
+ if (mlen==0) { /* only literals => must be last "sequence", actually starting a new stream of sequences */
+ assert(storePos == storeEnd); /* must be last sequence */
+ ip = anchor + llen; /* last "sequence" is a bunch of literals => don't progress anchor */
+ continue; /* will finish */
+ }
+
+ assert(anchor + llen <= iend);
+ ZSTD_updateStats(optStatePtr, llen, anchor, offBase, mlen);
+ ZSTD_storeSeq(seqStore, llen, anchor, iend, offBase, mlen);
+ anchor += advance;
+ ip = anchor;
+ } }
+ ZSTD_setBasePrices(optStatePtr, optLevel);
+ }
+ } /* while (ip < ilimit) */
+
+ /* Return the last literals size */
+ return (size_t)(iend - anchor);
+}
+
+static size_t ZSTD_compressBlock_opt0(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize, const ZSTD_dictMode_e dictMode)
+{
+ return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 0 /* optLevel */, dictMode);
+}
+
+static size_t ZSTD_compressBlock_opt2(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize, const ZSTD_dictMode_e dictMode)
+{
+ return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, src, srcSize, 2 /* optLevel */, dictMode);
+}
+
+size_t ZSTD_compressBlock_btopt(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize)
+{
+ DEBUGLOG(5, "ZSTD_compressBlock_btopt");
+ return ZSTD_compressBlock_opt0(ms, seqStore, rep, src, srcSize, ZSTD_noDict);
+}
+
+
+
+
+/* ZSTD_initStats_ultra():
+ * make a first compression pass, just to seed stats with more accurate starting values.
+ * only works on first block, with no dictionary and no ldm.
+ * this function cannot error out, its narrow contract must be respected.
+ */
+static void
+ZSTD_initStats_ultra(ZSTD_matchState_t* ms,
+ seqStore_t* seqStore,
+ U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize)
+{
+ U32 tmpRep[ZSTD_REP_NUM]; /* updated rep codes will sink here */
+ ZSTD_memcpy(tmpRep, rep, sizeof(tmpRep));
+
+ DEBUGLOG(4, "ZSTD_initStats_ultra (srcSize=%zu)", srcSize);
+ assert(ms->opt.litLengthSum == 0); /* first block */
+ assert(seqStore->sequences == seqStore->sequencesStart); /* no ldm */
+ assert(ms->window.dictLimit == ms->window.lowLimit); /* no dictionary */
+ assert(ms->window.dictLimit - ms->nextToUpdate <= 1); /* no prefix (note: intentional overflow, defined as 2-complement) */
+
+ ZSTD_compressBlock_opt2(ms, seqStore, tmpRep, src, srcSize, ZSTD_noDict); /* generate stats into ms->opt*/
+
+ /* invalidate first scan from history, only keep entropy stats */
+ ZSTD_resetSeqStore(seqStore);
+ ms->window.base -= srcSize;
+ ms->window.dictLimit += (U32)srcSize;
+ ms->window.lowLimit = ms->window.dictLimit;
+ ms->nextToUpdate = ms->window.dictLimit;
+
+}
+
+size_t ZSTD_compressBlock_btultra(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize)
+{
+ DEBUGLOG(5, "ZSTD_compressBlock_btultra (srcSize=%zu)", srcSize);
+ return ZSTD_compressBlock_opt2(ms, seqStore, rep, src, srcSize, ZSTD_noDict);
+}
+
+size_t ZSTD_compressBlock_btultra2(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize)
+{
+ U32 const curr = (U32)((const BYTE*)src - ms->window.base);
+ DEBUGLOG(5, "ZSTD_compressBlock_btultra2 (srcSize=%zu)", srcSize);
+
+ /* 2-passes strategy:
+ * this strategy makes a first pass over first block to collect statistics
+ * in order to seed next round's statistics with it.
+ * After 1st pass, function forgets history, and starts a new block.
+ * Consequently, this can only work if no data has been previously loaded in tables,
+ * aka, no dictionary, no prefix, no ldm preprocessing.
+ * The compression ratio gain is generally small (~0.5% on first block),
+ ** the cost is 2x cpu time on first block. */
+ assert(srcSize <= ZSTD_BLOCKSIZE_MAX);
+ if ( (ms->opt.litLengthSum==0) /* first block */
+ && (seqStore->sequences == seqStore->sequencesStart) /* no ldm */
+ && (ms->window.dictLimit == ms->window.lowLimit) /* no dictionary */
+ && (curr == ms->window.dictLimit) /* start of frame, nothing already loaded nor skipped */
+ && (srcSize > ZSTD_PREDEF_THRESHOLD) /* input large enough to not employ default stats */
+ ) {
+ ZSTD_initStats_ultra(ms, seqStore, rep, src, srcSize);
+ }
+
+ return ZSTD_compressBlock_opt2(ms, seqStore, rep, src, srcSize, ZSTD_noDict);
+}
+
+size_t ZSTD_compressBlock_btopt_dictMatchState(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize)
+{
+ return ZSTD_compressBlock_opt0(ms, seqStore, rep, src, srcSize, ZSTD_dictMatchState);
+}
+
+size_t ZSTD_compressBlock_btultra_dictMatchState(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize)
+{
+ return ZSTD_compressBlock_opt2(ms, seqStore, rep, src, srcSize, ZSTD_dictMatchState);
+}
+
+size_t ZSTD_compressBlock_btopt_extDict(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize)
+{
+ return ZSTD_compressBlock_opt0(ms, seqStore, rep, src, srcSize, ZSTD_extDict);
+}
+
+size_t ZSTD_compressBlock_btultra_extDict(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ const void* src, size_t srcSize)
+{
+ return ZSTD_compressBlock_opt2(ms, seqStore, rep, src, srcSize, ZSTD_extDict);
+}
+
+/* note : no btultra2 variant for extDict nor dictMatchState,
+ * because btultra2 is not meant to work with dictionaries
+ * and is only specific for the first block (no prefix) */
notaz.gp2x.de / pcsx_rearmed.git / blobdiff