/*-*************************************
* 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_CCtx* zc,
- const BYTE* const ip, const BYTE* const iend,
- U32 nbCompares, U32 const mls, U32 const extDict)
+#define ZSTD_DUBT_UNSORTED ((U32)(-1))
+
+void ZSTD_updateDUBT(ZSTD_CCtx* zc,
+ const BYTE* ip, const BYTE* iend,
+ U32 mls)
+{
+ U32* const hashTable = zc->hashTable;
+ U32 const hashLog = zc->appliedParams.cParams.hashLog;
+
+ U32* const bt = zc->chainTable;
+ U32 const btLog = zc->appliedParams.cParams.chainLog - 1;
+ U32 const btMask = (1 << btLog) - 1;
+
+ const BYTE* const base = zc->base;
+ U32 const target = (U32)(ip - base);
+ U32 idx = zc->nextToUpdate;
+
+ DEBUGLOG(7, "ZSTD_updateDUBT, from %u to %u ",
+ idx, target);
+ assert(ip + 8 <= iend); /* condition for ZSTD_hashPtr */
+ (void)iend;
+
+
+ assert(idx >= zc->dictLimit); /* condition for valid base+idx */
+ for ( ; idx < target ; idx++) {
+ size_t const h = ZSTD_hashPtr(base + idx, hashLog, mls); /* assumption : ip + 8 <= iend */
+ U32 const matchIndex = hashTable[h];
+
+ U32* const nextCandidatePtr = bt + 2*(idx&btMask);
+ U32* const sortMarkPtr = nextCandidatePtr + 1;
+
+ hashTable[h] = idx; /* Update Hash Table */
+ *nextCandidatePtr = matchIndex; /* update BT like a chain */
+ *sortMarkPtr = ZSTD_DUBT_UNSORTED;
+ }
+ zc->nextToUpdate = target;
+}
+
+
+/** ZSTD_insertDUBT1() :
+ * sort one already inserted but unsorted position
+ * assumption : current >= btlow == (current - btmask)
+ * doesn't fail */
+static void ZSTD_insertDUBT1(ZSTD_CCtx* zc,
+ U32 current, const BYTE* iend,
+ U32 nbCompares, U32 btLow, int extDict)
{
- U32* const hashTable = zc->hashTable;
- U32 const hashLog = zc->appliedParams.cParams.hashLog;
- size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
U32* const bt = zc->chainTable;
U32 const btLog = zc->appliedParams.cParams.chainLog - 1;
U32 const btMask = (1 << btLog) - 1;
- U32 matchIndex = hashTable[h];
size_t commonLengthSmaller=0, commonLengthLarger=0;
const BYTE* const base = zc->base;
+ const BYTE* const ip = base + current;
const BYTE* const dictBase = zc->dictBase;
const U32 dictLimit = zc->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 matchIndex = *smallerPtr;
U32 dummy32; /* to be nullified at the end */
U32 const windowLow = zc->lowLimit;
- U32 matchEndIdx = current+8+1;
- size_t bestLength = 8;
-#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);
+ DEBUGLOG(8, "ZSTD_insertDUBT1 (%u)", current);
+ assert(current >= btLow);
- assert(ip <= iend-8); /* required for h calculation */
- hashTable[h] = current; /* Update Hash Table */
+ if (extDict && (current < dictLimit)) { /* do not sort candidates in _extDict (simplification, for easier ZSTD_count, detrimental to compression ratio in streaming mode) */
+ *largerPtr = *smallerPtr = 0;
+ return;
+ }
+ assert(current >= dictLimit); /* ip=base+current within current memory segment */
while (nbCompares-- && (matchIndex > windowLow)) {
U32* const nextPtr = bt + 2*(matchIndex & btMask);
size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
+ DEBUGLOG(8, "ZSTD_insertDUBT1: comparing %u with %u", current, matchIndex);
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;
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 */
}
*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 */
+ DEBUGLOG(8, "ZSTD_insertDUBT1: selecting next candidate from %u (>btLow=%u) => %u",
+ matchIndex, btLow, nextPtr[1]);
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 {
*largerPtr = matchIndex;
commonLengthLarger = matchLength;
if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop searching */
+ DEBUGLOG(8, "ZSTD_insertDUBT1: selecting next candidate from %u (>btLow=%u) => %u",
+ matchIndex, btLow, nextPtr[0]);
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_CCtx* zc,
- const BYTE* const ip, const BYTE* const iend,
- const U32 nbCompares, const U32 mls, const U32 extDict)
-{
- const BYTE* const base = zc->base;
- U32 const target = (U32)(ip - base);
- U32 idx = zc->nextToUpdate;
- DEBUGLOG(7, "ZSTD_updateTree_internal, from %u to %u (extDict:%u)",
- idx, target, extDict);
-
- while(idx < target)
- idx += ZSTD_insertBt1(zc, base+idx, iend, nbCompares, mls, extDict);
- zc->nextToUpdate = target;
-}
-
-void ZSTD_updateTree(ZSTD_CCtx* zc,
- const BYTE* const ip, const BYTE* const iend,
- const U32 nbCompares, const U32 mls)
-{
- ZSTD_updateTree_internal(zc, ip, iend, nbCompares, mls, 0 /*extDict*/);
-}
-
-void ZSTD_updateTree_extDict(ZSTD_CCtx* zc,
- const BYTE* const ip, const BYTE* const iend,
- const U32 nbCompares, const U32 mls)
-{
- ZSTD_updateTree_internal(zc, ip, iend, nbCompares, mls, 1 /*extDict*/);
}
static size_t ZSTD_insertBtAndFindBestMatch (
- ZSTD_CCtx* zc,
- const BYTE* const ip, const BYTE* const iend,
- size_t* offsetPtr,
- U32 nbCompares, const U32 mls,
- U32 extDict)
+ ZSTD_CCtx* zc,
+ const BYTE* const ip, const BYTE* const iend,
+ size_t* offsetPtr,
+ U32 nbCompares, const U32 mls,
+ U32 extDict)
{
U32* const hashTable = zc->hashTable;
U32 const hashLog = zc->appliedParams.cParams.hashLog;
size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
+ U32 matchIndex = hashTable[h];
+
+ const BYTE* const base = zc->base;
+ U32 const current = (U32)(ip-base);
+
U32* const bt = zc->chainTable;
U32 const btLog = zc->appliedParams.cParams.chainLog - 1;
U32 const btMask = (1 << btLog) - 1;
- U32 matchIndex = hashTable[h];
- size_t commonLengthSmaller=0, commonLengthLarger=0;
- const BYTE* const base = zc->base;
- const BYTE* const dictBase = zc->dictBase;
- const U32 dictLimit = zc->dictLimit;
- const BYTE* const dictEnd = dictBase + dictLimit;
- const BYTE* const prefixStart = base + dictLimit;
- const U32 current = (U32)(ip-base);
- const U32 btLow = btMask >= current ? 0 : current - btMask;
- const U32 windowLow = zc->lowLimit;
- U32* smallerPtr = bt + 2*(current&btMask);
- U32* largerPtr = bt + 2*(current&btMask) + 1;
- U32 matchEndIdx = current+8+1;
- U32 dummy32; /* to be nullified at the end */
- size_t bestLength = 0;
+ U32 const btLow = (btMask >= current) ? 0 : current - btMask;
+
+ U32* nextCandidate = bt + 2*(matchIndex&btMask);
+ U32* unsortedMark = bt + 2*(matchIndex&btMask) + 1;
+ U32 nbCandidates = nbCompares;
+ U32 previousCandidate = 0;
+ DEBUGLOG(7, "ZSTD_insertBtAndFindBestMatch (%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 */
- const BYTE* match;
+ /* reach end of unsorted candidates list */
+ while ( (matchIndex > btLow)
+ && (*unsortedMark == ZSTD_DUBT_UNSORTED)
+ && (nbCandidates > 1) ) {
+ DEBUGLOG(8, "ZSTD_insertBtAndFindBestMatch: candidate %u is unsorted",
+ matchIndex);
+ *unsortedMark = previousCandidate;
+ previousCandidate = matchIndex;
+ matchIndex = *nextCandidate;
+ nextCandidate = bt + 2*(matchIndex&btMask);
+ unsortedMark = bt + 2*(matchIndex&btMask) + 1;
+ nbCandidates --;
+ }
- if ((!extDict) || (matchIndex+matchLength >= dictLimit)) {
- 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 ( (matchIndex > btLow)
+ && (*unsortedMark==ZSTD_DUBT_UNSORTED) ) {
+ DEBUGLOG(8, "ZSTD_insertBtAndFindBestMatch: nullify last unsorted candidate %u",
+ matchIndex);
+ *nextCandidate = *unsortedMark = 0; /* nullify last candidate if it's still unsorted (note : detrimental to compression ratio) */
+ }
+
+ /* batch sort stacked candidates */
+ matchIndex = previousCandidate;
+ while (matchIndex) { /* will end on matchIndex == 0 */
+ U32* const nextCandidateIdxPtr = bt + 2*(matchIndex&btMask) + 1;
+ U32 const nextCandidateIdx = *nextCandidateIdxPtr;
+ ZSTD_insertDUBT1(zc, matchIndex, iend,
+ nbCandidates, btLow, extDict);
+ matchIndex = nextCandidateIdx;
+ nbCandidates++;
+ }
- if (matchLength > bestLength) {
- if (matchLength > matchEndIdx - matchIndex)
- matchEndIdx = matchIndex + (U32)matchLength;
- if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(current-matchIndex+1) - ZSTD_highbit32((U32)offsetPtr[0]+1)) )
- bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + current - matchIndex;
- if (ip+matchLength == iend) { /* equal : no way to know if inf or sup */
- break; /* drop, to guarantee consistency (miss a little bit of compression) */
+ /* find longest match */
+ { 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 windowLow = zc->lowLimit;
+ U32* smallerPtr = bt + 2*(current&btMask);
+ U32* largerPtr = bt + 2*(current&btMask) + 1;
+ U32 matchEndIdx = current+8+1;
+ U32 dummy32; /* to be nullified at the end */
+ size_t bestLength = 0;
+
+ matchIndex = hashTable[h];
+ 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;
+
+ if ((!extDict) || (matchIndex+matchLength >= dictLimit)) {
+ 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 (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];
- } }
+ if (matchLength > bestLength) {
+ if (matchLength > matchEndIdx - matchIndex)
+ matchEndIdx = matchIndex + (U32)matchLength;
+ if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(current-matchIndex+1) - ZSTD_highbit32((U32)offsetPtr[0]+1)) )
+ bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + current - matchIndex;
+ if (ip+matchLength == iend) { /* equal : no way to know if inf or sup */
+ break; /* drop, to guarantee consistency (miss a little bit of compression) */
+ }
+ }
- *smallerPtr = *largerPtr = 0;
+ 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;
- assert(matchEndIdx > current+8);
- zc->nextToUpdate = matchEndIdx - 8; /* skip repetitive patterns */
- return bestLength;
+ assert(matchEndIdx > current+8); /* ensure nextToUpdate is increased */
+ zc->nextToUpdate = matchEndIdx - 8; /* skip repetitive patterns */
+ if (bestLength)
+ DEBUGLOG(7, "ZSTD_insertBtAndFindBestMatch(%u) : found match of length %u",
+ current, (U32)bestLength);
+ return bestLength;
+ }
}
const U32 maxNbAttempts, const U32 mls)
{
if (ip < zc->base + zc->nextToUpdate) return 0; /* skipped area */
- ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls);
+ ZSTD_updateDUBT(zc, ip, iLimit, mls);
return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 0);
}
const U32 maxNbAttempts, const U32 mls)
{
if (ip < zc->base + zc->nextToUpdate) return 0; /* skipped area */
- ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls);
+ ZSTD_updateDUBT(zc, ip, iLimit, mls);
return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 1);
}
/*-*************************************
* 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_CCtx* zc,
+ const BYTE* const ip, const BYTE* const iend,
+ U32 nbCompares, U32 const mls, U32 const extDict)
+{
+ U32* const hashTable = zc->hashTable;
+ U32 const hashLog = zc->appliedParams.cParams.hashLog;
+ size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
+ U32* const bt = zc->chainTable;
+ U32 const btLog = zc->appliedParams.cParams.chainLog - 1;
+ U32 const btMask = (1 << btLog) - 1;
+ U32 matchIndex = hashTable[h];
+ size_t commonLengthSmaller=0, commonLengthLarger=0;
+ const BYTE* const base = zc->base;
+ const BYTE* const dictBase = zc->dictBase;
+ const U32 dictLimit = zc->dictLimit;
+ const BYTE* const dictEnd = dictBase + dictLimit;
+ const BYTE* const prefixStart = base + dictLimit;
+ const 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 = zc->lowLimit;
+ U32 matchEndIdx = current+8+1;
+ size_t bestLength = 8;
+#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_CCtx* zc,
+ const BYTE* const ip, const BYTE* const iend,
+ const U32 nbCompares, const U32 mls, const U32 extDict)
+{
+ const BYTE* const base = zc->base;
+ U32 const target = (U32)(ip - base);
+ U32 idx = zc->nextToUpdate;
+ DEBUGLOG(7, "ZSTD_updateTree_internal, from %u to %u (extDict:%u)",
+ idx, target, extDict);
+
+ while(idx < target)
+ idx += ZSTD_insertBt1(zc, base+idx, iend, nbCompares, mls, extDict);
+ zc->nextToUpdate = target;
+}
+
+void ZSTD_updateTree(ZSTD_CCtx* zc,
+ const BYTE* const ip, const BYTE* const iend,
+ const U32 nbCompares, const U32 mls)
+{
+ ZSTD_updateTree_internal(zc, ip, iend, nbCompares, mls, 0 /*extDict*/);
+}
+
+void ZSTD_updateTree_extDict(ZSTD_CCtx* zc,
+ const BYTE* const ip, const BYTE* const iend,
+ const U32 nbCompares, const U32 mls)
+{
+ ZSTD_updateTree_internal(zc, ip, iend, nbCompares, mls, 1 /*extDict*/);
+}
+
+
FORCE_INLINE_TEMPLATE
U32 ZSTD_insertBtAndGetAllMatches (
ZSTD_CCtx* zc,
projects / thirdparty / zstd.git / commitdiff
