VOL-1967 move api-server to separate repository
Current with voltha-go acf0adaf2d91ae72b55192cc8a939e0485918d16
Change-Id: I000ea6be0789e20c922bd671562b58a7120892ae
diff --git a/vendor/github.com/DataDog/zstd/zstd_opt.c b/vendor/github.com/DataDog/zstd/zstd_opt.c
new file mode 100644
index 0000000..f63f0c5
--- /dev/null
+++ b/vendor/github.com/DataDog/zstd/zstd_opt.c
@@ -0,0 +1,923 @@
+/*
+ * Copyright (c) 2016-present, Przemyslaw Skibinski, Yann Collet, Facebook, Inc.
+ * 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 "zstd_opt.h"
+
+
+#define ZSTD_LITFREQ_ADD 2 /* scaling factor for litFreq, so that frequencies adapt faster to new stats. Also used for matchSum (?) */
+#define ZSTD_FREQ_DIV 4 /* log factor when using previous stats to init next stats */
+#define ZSTD_MAX_PRICE (1<<30)
+
+
+/*-*************************************
+* Price functions for optimal parser
+***************************************/
+static void ZSTD_setLog2Prices(optState_t* optPtr)
+{
+ optPtr->log2litSum = ZSTD_highbit32(optPtr->litSum+1);
+ optPtr->log2litLengthSum = ZSTD_highbit32(optPtr->litLengthSum+1);
+ optPtr->log2matchLengthSum = ZSTD_highbit32(optPtr->matchLengthSum+1);
+ optPtr->log2offCodeSum = ZSTD_highbit32(optPtr->offCodeSum+1);
+}
+
+
+static void ZSTD_rescaleFreqs(optState_t* const optPtr,
+ const BYTE* const src, size_t const srcSize)
+{
+ optPtr->staticPrices = 0;
+
+ if (optPtr->litLengthSum == 0) { /* first init */
+ unsigned u;
+ if (srcSize <= 1024) optPtr->staticPrices = 1;
+
+ assert(optPtr->litFreq!=NULL);
+ for (u=0; u<=MaxLit; u++)
+ optPtr->litFreq[u] = 0;
+ for (u=0; u<srcSize; u++)
+ optPtr->litFreq[src[u]]++;
+ optPtr->litSum = 0;
+ for (u=0; u<=MaxLit; u++) {
+ optPtr->litFreq[u] = 1 + (optPtr->litFreq[u] >> ZSTD_FREQ_DIV);
+ optPtr->litSum += optPtr->litFreq[u];
+ }
+
+ for (u=0; u<=MaxLL; u++)
+ optPtr->litLengthFreq[u] = 1;
+ optPtr->litLengthSum = MaxLL+1;
+ for (u=0; u<=MaxML; u++)
+ optPtr->matchLengthFreq[u] = 1;
+ optPtr->matchLengthSum = MaxML+1;
+ for (u=0; u<=MaxOff; u++)
+ optPtr->offCodeFreq[u] = 1;
+ optPtr->offCodeSum = (MaxOff+1);
+
+ } else {
+ unsigned u;
+
+ optPtr->litSum = 0;
+ for (u=0; u<=MaxLit; u++) {
+ optPtr->litFreq[u] = 1 + (optPtr->litFreq[u] >> (ZSTD_FREQ_DIV+1));
+ optPtr->litSum += optPtr->litFreq[u];
+ }
+ optPtr->litLengthSum = 0;
+ for (u=0; u<=MaxLL; u++) {
+ optPtr->litLengthFreq[u] = 1 + (optPtr->litLengthFreq[u]>>(ZSTD_FREQ_DIV+1));
+ optPtr->litLengthSum += optPtr->litLengthFreq[u];
+ }
+ optPtr->matchLengthSum = 0;
+ for (u=0; u<=MaxML; u++) {
+ optPtr->matchLengthFreq[u] = 1 + (optPtr->matchLengthFreq[u]>>ZSTD_FREQ_DIV);
+ optPtr->matchLengthSum += optPtr->matchLengthFreq[u];
+ }
+ optPtr->offCodeSum = 0;
+ for (u=0; u<=MaxOff; u++) {
+ optPtr->offCodeFreq[u] = 1 + (optPtr->offCodeFreq[u]>>ZSTD_FREQ_DIV);
+ optPtr->offCodeSum += optPtr->offCodeFreq[u];
+ }
+ }
+
+ ZSTD_setLog2Prices(optPtr);
+}
+
+
+/* ZSTD_rawLiteralsCost() :
+ * cost of literals (only) in given segment (which length can be null)
+ * does not include cost of literalLength symbol */
+static U32 ZSTD_rawLiteralsCost(const BYTE* const literals, U32 const litLength,
+ const optState_t* const optPtr)
+{
+ if (optPtr->staticPrices) return (litLength*6); /* 6 bit per literal - no statistic used */
+ if (litLength == 0) return 0;
+
+ /* literals */
+ { U32 u;
+ U32 cost = litLength * optPtr->log2litSum;
+ for (u=0; u < litLength; u++)
+ cost -= ZSTD_highbit32(optPtr->litFreq[literals[u]]+1);
+ return cost;
+ }
+}
+
+/* ZSTD_litLengthPrice() :
+ * cost of literalLength symbol */
+static U32 ZSTD_litLengthPrice(U32 const litLength, const optState_t* const optPtr)
+{
+ if (optPtr->staticPrices) return ZSTD_highbit32((U32)litLength+1);
+
+ /* literal Length */
+ { U32 const llCode = ZSTD_LLcode(litLength);
+ U32 const price = LL_bits[llCode] + optPtr->log2litLengthSum - ZSTD_highbit32(optPtr->litLengthFreq[llCode]+1);
+ return price;
+ }
+}
+
+/* ZSTD_litLengthPrice() :
+ * cost of the literal part of a sequence,
+ * including literals themselves, and literalLength symbol */
+static U32 ZSTD_fullLiteralsCost(const BYTE* const literals, U32 const litLength,
+ const optState_t* const optPtr)
+{
+ return ZSTD_rawLiteralsCost(literals, litLength, optPtr)
+ + ZSTD_litLengthPrice(litLength, optPtr);
+}
+
+/* ZSTD_litLengthContribution() :
+ * @return ( cost(litlength) - cost(0) )
+ * this value can then be added to rawLiteralsCost()
+ * to provide a cost which is directly comparable to a match ending at same position */
+static int ZSTD_litLengthContribution(U32 const litLength, const optState_t* const optPtr)
+{
+ if (optPtr->staticPrices) return ZSTD_highbit32(litLength+1);
+
+ /* literal Length */
+ { U32 const llCode = ZSTD_LLcode(litLength);
+ int const contribution = LL_bits[llCode]
+ + ZSTD_highbit32(optPtr->litLengthFreq[0]+1)
+ - ZSTD_highbit32(optPtr->litLengthFreq[llCode]+1);
+#if 1
+ return contribution;
+#else
+ return MAX(0, contribution); /* sometimes better, sometimes not ... */
+#endif
+ }
+}
+
+/* ZSTD_literalsContribution() :
+ * creates a fake cost for the literals part of a sequence
+ * which can be compared to the ending cost of a match
+ * should a new match start at this position */
+static int ZSTD_literalsContribution(const BYTE* const literals, U32 const litLength,
+ const optState_t* const optPtr)
+{
+ int const contribution = ZSTD_rawLiteralsCost(literals, litLength, optPtr)
+ + ZSTD_litLengthContribution(litLength, optPtr);
+ return contribution;
+}
+
+/* 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.
+ * optLevel: when <2, favors small offset for decompression speed (improved cache efficiency) */
+FORCE_INLINE_TEMPLATE U32 ZSTD_getMatchPrice(
+ U32 const offset, U32 const matchLength,
+ const optState_t* const optPtr,
+ int const optLevel)
+{
+ U32 price;
+ U32 const offCode = ZSTD_highbit32(offset+1);
+ U32 const mlBase = matchLength - MINMATCH;
+ assert(matchLength >= MINMATCH);
+
+ if (optPtr->staticPrices) /* fixed scheme, do not use statistics */
+ return ZSTD_highbit32((U32)mlBase+1) + 16 + offCode;
+
+ price = offCode + optPtr->log2offCodeSum - ZSTD_highbit32(optPtr->offCodeFreq[offCode]+1);
+ if ((optLevel<2) /*static*/ && offCode >= 20) price += (offCode-19)*2; /* handicap for long distance offsets, favor decompression speed */
+
+ /* match Length */
+ { U32 const mlCode = ZSTD_MLcode(mlBase);
+ price += ML_bits[mlCode] + optPtr->log2matchLengthSum - ZSTD_highbit32(optPtr->matchLengthFreq[mlCode]+1);
+ }
+
+ DEBUGLOG(8, "ZSTD_getMatchPrice(ml:%u) = %u", matchLength, price);
+ return price;
+}
+
+static void ZSTD_updateStats(optState_t* const optPtr,
+ U32 litLength, const BYTE* literals,
+ U32 offsetCode, U32 matchLength)
+{
+ /* literals */
+ { 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++;
+ }
+
+ /* match offset code (0-2=>repCode; 3+=>offset+2) */
+ { U32 const offCode = ZSTD_highbit32(offsetCode+1);
+ 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 (ZSTD_matchState_t* ms, const BYTE* const ip)
+{
+ U32* const hashTable3 = ms->hashTable3;
+ U32 const hashLog3 = ms->hashLog3;
+ const BYTE* const base = ms->window.base;
+ U32 idx = ms->nextToUpdate3;
+ U32 const target = ms->nextToUpdate3 = (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++;
+ }
+
+ return hashTable3[hash3];
+}
+
+
+/*-*************************************
+* Binary Tree search
+***************************************/
+/** ZSTD_insertBt1() : add one or multiple positions to tree.
+ * ip : assumed <= iend-8 .
+ * @return : nb of positions added */
+static U32 ZSTD_insertBt1(
+ ZSTD_matchState_t* ms, ZSTD_compressionParameters const* cParams,
+ const BYTE* const ip, const BYTE* const iend,
+ U32 const mls, U32 const extDict)
+{
+ 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 current = (U32)(ip-base);
+ const U32 btLow = btMask >= current ? 0 : current - btMask;
+ U32* smallerPtr = bt + 2*(current&btMask);
+ U32* largerPtr = smallerPtr + 1;
+ U32 dummy32; /* to be nullified at the end */
+ U32 const windowLow = ms->window.lowLimit;
+ U32 matchEndIdx = current+8+1;
+ size_t bestLength = 8;
+ U32 nbCompares = 1U << cParams->searchLog;
+#ifdef ZSTD_C_PREDICT
+ U32 predictedSmall = *(bt + 2*((current-1)&btMask) + 0);
+ U32 predictedLarge = *(bt + 2*((current-1)&btMask) + 1);
+ predictedSmall += (predictedSmall>0);
+ predictedLarge += (predictedLarge>0);
+#endif /* ZSTD_C_PREDICT */
+
+ DEBUGLOG(8, "ZSTD_insertBt1 (%u)", current);
+
+ assert(ip <= iend-8); /* required for h calculation */
+ hashTable[h] = current; /* Update Hash Table */
+
+ while (nbCompares-- && (matchIndex > windowLow)) {
+ U32* const nextPtr = bt + 2*(matchIndex & btMask);
+ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
+ assert(matchIndex < current);
+
+#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 extDict is incorrectly set to 0 */
+ 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;
+ if (bestLength > 384) return MIN(192, (U32)(bestLength - 384)); /* speed optimization */
+ assert(matchEndIdx > current + 8);
+ return matchEndIdx - (current + 8);
+}
+
+FORCE_INLINE_TEMPLATE
+void ZSTD_updateTree_internal(
+ ZSTD_matchState_t* ms, ZSTD_compressionParameters const* cParams,
+ const BYTE* const ip, const BYTE* const iend,
+ const U32 mls, const U32 extDict)
+{
+ const BYTE* const base = ms->window.base;
+ U32 const target = (U32)(ip - base);
+ U32 idx = ms->nextToUpdate;
+ DEBUGLOG(7, "ZSTD_updateTree_internal, from %u to %u (extDict:%u)",
+ idx, target, extDict);
+
+ while(idx < target)
+ idx += ZSTD_insertBt1(ms, cParams, base+idx, iend, mls, extDict);
+ ms->nextToUpdate = target;
+}
+
+void ZSTD_updateTree(
+ ZSTD_matchState_t* ms, ZSTD_compressionParameters const* cParams,
+ const BYTE* ip, const BYTE* iend)
+{
+ ZSTD_updateTree_internal(ms, cParams, ip, iend, cParams->searchLength, 0 /*extDict*/);
+}
+
+FORCE_INLINE_TEMPLATE
+U32 ZSTD_insertBtAndGetAllMatches (
+ ZSTD_matchState_t* ms, ZSTD_compressionParameters const* cParams,
+ const BYTE* const ip, const BYTE* const iLimit, int const extDict,
+ U32 rep[ZSTD_REP_NUM], U32 const ll0,
+ ZSTD_match_t* matches, const U32 lengthToBeat, U32 const mls /* template */)
+{
+ U32 const sufficient_len = MIN(cParams->targetLength, ZSTD_OPT_NUM -1);
+ const BYTE* const base = ms->window.base;
+ U32 const current = (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 >= current ? 0 : current - btMask;
+ U32 const windowLow = ms->window.lowLimit;
+ U32* smallerPtr = bt + 2*(current&btMask);
+ U32* largerPtr = bt + 2*(current&btMask) + 1;
+ U32 matchEndIdx = current+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;
+
+ size_t bestLength = lengthToBeat-1;
+ DEBUGLOG(7, "ZSTD_insertBtAndGetAllMatches");
+
+ /* check repCode */
+ { 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 = current - repOffset;
+ U32 repLen = 0;
+ assert(current >= dictLimit);
+ if (repOffset-1 /* intentional overflow, discards 0 and -1 */ < current-dictLimit) { /* equivalent to `current > repIndex >= dictLimit` */
+ if (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repOffset, minMatch)) {
+ repLen = (U32)ZSTD_count(ip+minMatch, ip+minMatch-repOffset, iLimit) + minMatch;
+ }
+ } else { /* repIndex < dictLimit || repIndex >= current */
+ const BYTE* const repMatch = dictBase + repIndex;
+ assert(current >= windowLow);
+ if ( extDict /* this case only valid in extDict mode */
+ && ( ((repOffset-1) /*intentional overflow*/ < current - windowLow) /* equivalent to `current > 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;
+ } }
+ /* save longer solution */
+ if (repLen > bestLength) {
+ DEBUGLOG(8, "found rep-match %u of length %u",
+ repCode - ll0, (U32)repLen);
+ bestLength = repLen;
+ matches[mnum].off = repCode - ll0;
+ 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, ip);
+ if ((matchIndex3 > windowLow)
+ & (current - matchIndex3 < (1<<18)) /*heuristic : longer distance likely too expensive*/ ) {
+ size_t mlen;
+ if ((!extDict) /*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(current > matchIndex3);
+ assert(mnum==0); /* no prior solution */
+ matches[0].off = (current - matchIndex3) + ZSTD_REP_MOVE;
+ matches[0].len = (U32)mlen;
+ mnum = 1;
+ if ( (mlen > sufficient_len) |
+ (ip+mlen == iLimit) ) { /* best possible length */
+ ms->nextToUpdate = current+1; /* skip insertion */
+ return 1;
+ } } } }
+
+ hashTable[h] = current; /* Update Hash Table */
+
+ while (nbCompares-- && (matchIndex > windowLow)) {
+ U32* const nextPtr = bt + 2*(matchIndex & btMask);
+ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
+ const BYTE* match;
+ assert(current > matchIndex);
+
+ if ((!extDict) || (matchIndex+matchLength >= dictLimit)) {
+ assert(matchIndex+matchLength >= dictLimit); /* ensure the condition is correct when !extDict */
+ match = base + matchIndex;
+ matchLength += ZSTD_count(ip+matchLength, match+matchLength, iLimit);
+ } else {
+ match = dictBase + matchIndex;
+ matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iLimit, dictEnd, prefixStart);
+ if (matchIndex+matchLength >= dictLimit)
+ match = base + matchIndex; /* prepare for match[matchLength] */
+ }
+
+ if (matchLength > bestLength) {
+ DEBUGLOG(8, "found match of length %u at distance %u",
+ (U32)matchLength, current - matchIndex);
+ assert(matchEndIdx > matchIndex);
+ if (matchLength > matchEndIdx - matchIndex)
+ matchEndIdx = matchIndex + (U32)matchLength;
+ bestLength = matchLength;
+ matches[mnum].off = (current - matchIndex) + ZSTD_REP_MOVE;
+ 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 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(matchEndIdx > current+8);
+ ms->nextToUpdate = matchEndIdx - 8; /* skip repetitive patterns */
+ return mnum;
+}
+
+
+FORCE_INLINE_TEMPLATE U32 ZSTD_BtGetAllMatches (
+ ZSTD_matchState_t* ms, ZSTD_compressionParameters const* cParams,
+ const BYTE* ip, const BYTE* const iHighLimit, int const extDict,
+ U32 rep[ZSTD_REP_NUM], U32 const ll0,
+ ZSTD_match_t* matches, U32 const lengthToBeat)
+{
+ U32 const matchLengthSearch = cParams->searchLength;
+ DEBUGLOG(7, "ZSTD_BtGetAllMatches");
+ if (ip < ms->window.base + ms->nextToUpdate) return 0; /* skipped area */
+ ZSTD_updateTree_internal(ms, cParams, ip, iHighLimit, matchLengthSearch, extDict);
+ switch(matchLengthSearch)
+ {
+ case 3 : return ZSTD_insertBtAndGetAllMatches(ms, cParams, ip, iHighLimit, extDict, rep, ll0, matches, lengthToBeat, 3);
+ default :
+ case 4 : return ZSTD_insertBtAndGetAllMatches(ms, cParams, ip, iHighLimit, extDict, rep, ll0, matches, lengthToBeat, 4);
+ case 5 : return ZSTD_insertBtAndGetAllMatches(ms, cParams, ip, iHighLimit, extDict, rep, ll0, matches, lengthToBeat, 5);
+ case 7 :
+ case 6 : return ZSTD_insertBtAndGetAllMatches(ms, cParams, ip, iHighLimit, extDict, rep, ll0, matches, lengthToBeat, 6);
+ }
+}
+
+
+/*-*******************************
+* Optimal parser
+*********************************/
+typedef struct repcodes_s {
+ U32 rep[3];
+} repcodes_t;
+
+repcodes_t ZSTD_updateRep(U32 const rep[3], U32 const offset, U32 const ll0)
+{
+ repcodes_t newReps;
+ if (offset >= ZSTD_REP_NUM) { /* full offset */
+ newReps.rep[2] = rep[1];
+ newReps.rep[1] = rep[0];
+ newReps.rep[0] = offset - ZSTD_REP_MOVE;
+ } else { /* repcode */
+ U32 const repCode = offset + ll0;
+ if (repCode > 0) { /* note : if repCode==0, no change */
+ U32 const currentOffset = (repCode==ZSTD_REP_NUM) ? (rep[0] - 1) : rep[repCode];
+ newReps.rep[2] = (repCode >= 2) ? rep[1] : rep[2];
+ newReps.rep[1] = rep[0];
+ newReps.rep[0] = currentOffset;
+ } else { /* repCode == 0 */
+ memcpy(&newReps, rep, sizeof(newReps));
+ }
+ }
+ return newReps;
+}
+
+
+typedef struct {
+ const BYTE* anchor;
+ U32 litlen;
+ U32 rawLitCost;
+} cachedLiteralPrice_t;
+
+static U32 ZSTD_rawLiteralsCost_cached(
+ cachedLiteralPrice_t* const cachedLitPrice,
+ const BYTE* const anchor, U32 const litlen,
+ const optState_t* const optStatePtr)
+{
+ U32 startCost;
+ U32 remainingLength;
+ const BYTE* startPosition;
+
+ if (anchor == cachedLitPrice->anchor) {
+ startCost = cachedLitPrice->rawLitCost;
+ startPosition = anchor + cachedLitPrice->litlen;
+ assert(litlen >= cachedLitPrice->litlen);
+ remainingLength = litlen - cachedLitPrice->litlen;
+ } else {
+ startCost = 0;
+ startPosition = anchor;
+ remainingLength = litlen;
+ }
+
+ { U32 const rawLitCost = startCost + ZSTD_rawLiteralsCost(startPosition, remainingLength, optStatePtr);
+ cachedLitPrice->anchor = anchor;
+ cachedLitPrice->litlen = litlen;
+ cachedLitPrice->rawLitCost = rawLitCost;
+ return rawLitCost;
+ }
+}
+
+static U32 ZSTD_fullLiteralsCost_cached(
+ cachedLiteralPrice_t* const cachedLitPrice,
+ const BYTE* const anchor, U32 const litlen,
+ const optState_t* const optStatePtr)
+{
+ return ZSTD_rawLiteralsCost_cached(cachedLitPrice, anchor, litlen, optStatePtr)
+ + ZSTD_litLengthPrice(litlen, optStatePtr);
+}
+
+static int ZSTD_literalsContribution_cached(
+ cachedLiteralPrice_t* const cachedLitPrice,
+ const BYTE* const anchor, U32 const litlen,
+ const optState_t* const optStatePtr)
+{
+ int const contribution = ZSTD_rawLiteralsCost_cached(cachedLitPrice, anchor, litlen, optStatePtr)
+ + ZSTD_litLengthContribution(litlen, optStatePtr);
+ return contribution;
+}
+
+FORCE_INLINE_TEMPLATE
+size_t ZSTD_compressBlock_opt_generic(ZSTD_matchState_t* ms,seqStore_t* seqStore,
+ U32 rep[ZSTD_REP_NUM],
+ ZSTD_compressionParameters const* cParams,
+ const void* src, size_t srcSize,
+ const int optLevel, const int extDict)
+{
+ 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;
+
+ U32 const sufficient_len = MIN(cParams->targetLength, ZSTD_OPT_NUM -1);
+ U32 const minMatch = (cParams->searchLength == 3) ? 3 : 4;
+
+ ZSTD_optimal_t* const opt = optStatePtr->priceTable;
+ ZSTD_match_t* const matches = optStatePtr->matchTable;
+ cachedLiteralPrice_t cachedLitPrice;
+
+ /* init */
+ DEBUGLOG(5, "ZSTD_compressBlock_opt_generic");
+ ms->nextToUpdate3 = ms->nextToUpdate;
+ ZSTD_rescaleFreqs(optStatePtr, (const BYTE*)src, srcSize);
+ ip += (ip==prefixStart);
+ memset(&cachedLitPrice, 0, sizeof(cachedLitPrice));
+
+ /* Match Loop */
+ while (ip < ilimit) {
+ U32 cur, last_pos = 0;
+ U32 best_mlen, best_off;
+
+ /* find first match */
+ { U32 const litlen = (U32)(ip - anchor);
+ U32 const ll0 = !litlen;
+ U32 const nbMatches = ZSTD_BtGetAllMatches(ms, cParams, ip, iend, extDict, rep, ll0, matches, minMatch);
+ 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 = 1;
+ opt[0].litlen = litlen;
+
+ /* large match -> immediate encoding */
+ { U32 const maxML = matches[nbMatches-1].len;
+ DEBUGLOG(7, "found %u matches of maxLength=%u and offset=%u at cPos=%u => start new serie",
+ nbMatches, maxML, matches[nbMatches-1].off, (U32)(ip-prefixStart));
+
+ if (maxML > sufficient_len) {
+ best_mlen = maxML;
+ best_off = matches[nbMatches-1].off;
+ DEBUGLOG(7, "large match (%u>%u), immediate encoding",
+ best_mlen, sufficient_len);
+ cur = 0;
+ last_pos = 1;
+ goto _shortestPath;
+ } }
+
+ /* set prices for first matches starting position == 0 */
+ { U32 const literalsPrice = ZSTD_fullLiteralsCost_cached(&cachedLitPrice, anchor, litlen, optStatePtr);
+ U32 pos;
+ U32 matchNb;
+ for (pos = 0; pos < minMatch; pos++) {
+ opt[pos].mlen = 1;
+ opt[pos].price = ZSTD_MAX_PRICE;
+ }
+ for (matchNb = 0; matchNb < nbMatches; matchNb++) {
+ U32 const offset = matches[matchNb].off;
+ U32 const end = matches[matchNb].len;
+ repcodes_t const repHistory = ZSTD_updateRep(rep, offset, ll0);
+ for ( ; pos <= end ; pos++ ) {
+ U32 const matchPrice = literalsPrice + ZSTD_getMatchPrice(offset, pos, optStatePtr, optLevel);
+ DEBUGLOG(7, "rPos:%u => set initial price : %u",
+ pos, matchPrice);
+ opt[pos].mlen = pos;
+ opt[pos].off = offset;
+ opt[pos].litlen = litlen;
+ opt[pos].price = matchPrice;
+ memcpy(opt[pos].rep, &repHistory, sizeof(repHistory));
+ } }
+ 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);
+
+ /* Fix current position with one literal if cheaper */
+ { U32 const litlen = (opt[cur-1].mlen == 1) ? opt[cur-1].litlen + 1 : 1;
+ int price; /* note : contribution can be negative */
+ if (cur > litlen) {
+ price = opt[cur - litlen].price + ZSTD_literalsContribution(inr-litlen, litlen, optStatePtr);
+ } else {
+ price = ZSTD_literalsContribution_cached(&cachedLitPrice, anchor, litlen, optStatePtr);
+ }
+ assert(price < 1000000000); /* overflow check */
+ if (price <= opt[cur].price) {
+ DEBUGLOG(7, "rPos:%u : better price (%u<%u) using literal",
+ cur, price, opt[cur].price);
+ opt[cur].mlen = 1;
+ opt[cur].off = 0;
+ opt[cur].litlen = litlen;
+ opt[cur].price = price;
+ memcpy(opt[cur].rep, opt[cur-1].rep, sizeof(opt[cur].rep));
+ } }
+
+ /* 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*/
+ && (opt[cur+1].price <= opt[cur].price) )
+ continue; /* skip unpromising positions; about ~+6% speed, -0.01 ratio */
+
+ { U32 const ll0 = (opt[cur].mlen != 1);
+ U32 const litlen = (opt[cur].mlen == 1) ? opt[cur].litlen : 0;
+ U32 const previousPrice = (cur > litlen) ? opt[cur-litlen].price : 0;
+ U32 const basePrice = previousPrice + ZSTD_fullLiteralsCost(inr-litlen, litlen, optStatePtr);
+ U32 const nbMatches = ZSTD_BtGetAllMatches(ms, cParams, inr, iend, extDict, opt[cur].rep, ll0, matches, minMatch);
+ U32 matchNb;
+ if (!nbMatches) continue;
+
+ { U32 const maxML = matches[nbMatches-1].len;
+ DEBUGLOG(7, "rPos:%u, found %u matches, of maxLength=%u",
+ cur, nbMatches, maxML);
+
+ if ( (maxML > sufficient_len)
+ | (cur + maxML >= ZSTD_OPT_NUM) ) {
+ best_mlen = maxML;
+ best_off = matches[nbMatches-1].off;
+ last_pos = cur + 1;
+ goto _shortestPath;
+ }
+ }
+
+ /* set prices using matches found at position == cur */
+ for (matchNb = 0; matchNb < nbMatches; matchNb++) {
+ U32 const offset = matches[matchNb].off;
+ repcodes_t const repHistory = ZSTD_updateRep(opt[cur].rep, offset, ll0);
+ U32 const lastML = matches[matchNb].len;
+ U32 const startML = (matchNb>0) ? matches[matchNb-1].len+1 : minMatch;
+ U32 mlen;
+
+ DEBUGLOG(7, "testing match %u => offCode=%u, mlen=%u, llen=%u",
+ matchNb, matches[matchNb].off, lastML, litlen);
+
+ for (mlen = lastML; mlen >= startML; mlen--) {
+ U32 const pos = cur + mlen;
+ int const price = basePrice + ZSTD_getMatchPrice(offset, mlen, optStatePtr, optLevel);
+
+ if ((pos > last_pos) || (price < opt[pos].price)) {
+ DEBUGLOG(7, "rPos:%u => new better price (%u<%u)",
+ pos, price, opt[pos].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;
+ memcpy(opt[pos].rep, &repHistory, sizeof(repHistory));
+ } else {
+ if (optLevel==0) break; /* gets ~+10% speed for about -0.01 ratio loss */
+ }
+ } } }
+ } /* for (cur = 1; cur <= last_pos; cur++) */
+
+ best_mlen = opt[last_pos].mlen;
+ best_off = opt[last_pos].off;
+ cur = last_pos - best_mlen;
+
+_shortestPath: /* cur, last_pos, best_mlen, best_off have to be set */
+ assert(opt[0].mlen == 1);
+
+ /* reverse traversal */
+ DEBUGLOG(7, "start reverse traversal (last_pos:%u, cur:%u)",
+ last_pos, cur);
+ { U32 selectedMatchLength = best_mlen;
+ U32 selectedOffset = best_off;
+ U32 pos = cur;
+ while (1) {
+ U32 const mlen = opt[pos].mlen;
+ U32 const off = opt[pos].off;
+ opt[pos].mlen = selectedMatchLength;
+ opt[pos].off = selectedOffset;
+ selectedMatchLength = mlen;
+ selectedOffset = off;
+ if (mlen > pos) break;
+ pos -= mlen;
+ } }
+
+ /* save sequences */
+ { U32 pos;
+ for (pos=0; pos < last_pos; ) {
+ U32 const llen = (U32)(ip - anchor);
+ U32 const mlen = opt[pos].mlen;
+ U32 const offset = opt[pos].off;
+ if (mlen == 1) { ip++; pos++; continue; } /* literal position => move on */
+ pos += mlen; ip += mlen;
+
+ /* repcodes update : like ZSTD_updateRep(), but update in place */
+ if (offset >= ZSTD_REP_NUM) { /* full offset */
+ rep[2] = rep[1];
+ rep[1] = rep[0];
+ rep[0] = offset - ZSTD_REP_MOVE;
+ } else { /* repcode */
+ U32 const repCode = offset + (llen==0);
+ if (repCode) { /* note : if repCode==0, no change */
+ U32 const currentOffset = (repCode==ZSTD_REP_NUM) ? (rep[0] - 1) : rep[repCode];
+ if (repCode >= 2) rep[2] = rep[1];
+ rep[1] = rep[0];
+ rep[0] = currentOffset;
+ }
+ }
+
+ ZSTD_updateStats(optStatePtr, llen, anchor, offset, mlen);
+ ZSTD_storeSeq(seqStore, llen, anchor, offset, mlen-MINMATCH);
+ anchor = ip;
+ } }
+ ZSTD_setLog2Prices(optStatePtr);
+ } /* while (ip < ilimit) */
+
+ /* Return the last literals size */
+ return iend - anchor;
+}
+
+
+size_t ZSTD_compressBlock_btopt(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ ZSTD_compressionParameters const* cParams, void const* src, size_t srcSize)
+{
+ DEBUGLOG(5, "ZSTD_compressBlock_btopt");
+ return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, cParams, src, srcSize, 0 /*optLevel*/, 0 /*extDict*/);
+}
+
+size_t ZSTD_compressBlock_btultra(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ ZSTD_compressionParameters const* cParams, void const* src, size_t srcSize)
+{
+ return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, cParams, src, srcSize, 2 /*optLevel*/, 0 /*extDict*/);
+}
+
+size_t ZSTD_compressBlock_btopt_extDict(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ ZSTD_compressionParameters const* cParams, void const* src, size_t srcSize)
+{
+ return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, cParams, src, srcSize, 0 /*optLevel*/, 1 /*extDict*/);
+}
+
+size_t ZSTD_compressBlock_btultra_extDict(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ ZSTD_compressionParameters const* cParams, void const* src, size_t srcSize)
+{
+ return ZSTD_compressBlock_opt_generic(ms, seqStore, rep, cParams, src, srcSize, 2 /*optLevel*/, 1 /*extDict*/);
+}