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-rw-r--r--lib/zstd/compress/zstd_double_fast.c519
1 files changed, 519 insertions, 0 deletions
diff --git a/lib/zstd/compress/zstd_double_fast.c b/lib/zstd/compress/zstd_double_fast.c
new file mode 100644
index 000000000000..b0424d23ac57
--- /dev/null
+++ b/lib/zstd/compress/zstd_double_fast.c
@@ -0,0 +1,519 @@
+/*
+ * Copyright (c) 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_double_fast.h"
+
+
+void ZSTD_fillDoubleHashTable(ZSTD_matchState_t* ms,
+ void const* end, ZSTD_dictTableLoadMethod_e dtlm)
+{
+ const ZSTD_compressionParameters* const cParams = &ms->cParams;
+ U32* const hashLarge = ms->hashTable;
+ U32 const hBitsL = cParams->hashLog;
+ U32 const mls = cParams->minMatch;
+ U32* const hashSmall = ms->chainTable;
+ U32 const hBitsS = cParams->chainLog;
+ const BYTE* const base = ms->window.base;
+ const BYTE* ip = base + ms->nextToUpdate;
+ const BYTE* const iend = ((const BYTE*)end) - HASH_READ_SIZE;
+ const U32 fastHashFillStep = 3;
+
+ /* Always insert every fastHashFillStep position into the hash tables.
+ * Insert the other positions into the large hash table if their entry
+ * is empty.
+ */
+ for (; ip + fastHashFillStep - 1 <= iend; ip += fastHashFillStep) {
+ U32 const curr = (U32)(ip - base);
+ U32 i;
+ for (i = 0; i < fastHashFillStep; ++i) {
+ size_t const smHash = ZSTD_hashPtr(ip + i, hBitsS, mls);
+ size_t const lgHash = ZSTD_hashPtr(ip + i, hBitsL, 8);
+ if (i == 0)
+ hashSmall[smHash] = curr + i;
+ if (i == 0 || hashLarge[lgHash] == 0)
+ hashLarge[lgHash] = curr + i;
+ /* Only load extra positions for ZSTD_dtlm_full */
+ if (dtlm == ZSTD_dtlm_fast)
+ break;
+ } }
+}
+
+
+FORCE_INLINE_TEMPLATE
+size_t ZSTD_compressBlock_doubleFast_generic(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize,
+ U32 const mls /* template */, ZSTD_dictMode_e const dictMode)
+{
+ ZSTD_compressionParameters const* cParams = &ms->cParams;
+ U32* const hashLong = ms->hashTable;
+ const U32 hBitsL = cParams->hashLog;
+ U32* const hashSmall = ms->chainTable;
+ const U32 hBitsS = cParams->chainLog;
+ const BYTE* const base = ms->window.base;
+ const BYTE* const istart = (const BYTE*)src;
+ const BYTE* ip = istart;
+ const BYTE* anchor = istart;
+ const U32 endIndex = (U32)((size_t)(istart - base) + srcSize);
+ /* presumes that, if there is a dictionary, it must be using Attach mode */
+ const U32 prefixLowestIndex = ZSTD_getLowestPrefixIndex(ms, endIndex, cParams->windowLog);
+ const BYTE* const prefixLowest = base + prefixLowestIndex;
+ const BYTE* const iend = istart + srcSize;
+ const BYTE* const ilimit = iend - HASH_READ_SIZE;
+ U32 offset_1=rep[0], offset_2=rep[1];
+ U32 offsetSaved = 0;
+
+ const ZSTD_matchState_t* const dms = ms->dictMatchState;
+ const ZSTD_compressionParameters* const dictCParams =
+ dictMode == ZSTD_dictMatchState ?
+ &dms->cParams : NULL;
+ const U32* const dictHashLong = dictMode == ZSTD_dictMatchState ?
+ dms->hashTable : NULL;
+ const U32* const dictHashSmall = dictMode == ZSTD_dictMatchState ?
+ dms->chainTable : NULL;
+ const U32 dictStartIndex = dictMode == ZSTD_dictMatchState ?
+ dms->window.dictLimit : 0;
+ const BYTE* const dictBase = dictMode == ZSTD_dictMatchState ?
+ dms->window.base : NULL;
+ const BYTE* const dictStart = dictMode == ZSTD_dictMatchState ?
+ dictBase + dictStartIndex : NULL;
+ const BYTE* const dictEnd = dictMode == ZSTD_dictMatchState ?
+ dms->window.nextSrc : NULL;
+ const U32 dictIndexDelta = dictMode == ZSTD_dictMatchState ?
+ prefixLowestIndex - (U32)(dictEnd - dictBase) :
+ 0;
+ const U32 dictHBitsL = dictMode == ZSTD_dictMatchState ?
+ dictCParams->hashLog : hBitsL;
+ const U32 dictHBitsS = dictMode == ZSTD_dictMatchState ?
+ dictCParams->chainLog : hBitsS;
+ const U32 dictAndPrefixLength = (U32)((ip - prefixLowest) + (dictEnd - dictStart));
+
+ DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_generic");
+
+ assert(dictMode == ZSTD_noDict || dictMode == ZSTD_dictMatchState);
+
+ /* if a dictionary is attached, it must be within window range */
+ if (dictMode == ZSTD_dictMatchState) {
+ assert(ms->window.dictLimit + (1U << cParams->windowLog) >= endIndex);
+ }
+
+ /* init */
+ ip += (dictAndPrefixLength == 0);
+ if (dictMode == ZSTD_noDict) {
+ U32 const curr = (U32)(ip - base);
+ U32 const windowLow = ZSTD_getLowestPrefixIndex(ms, curr, cParams->windowLog);
+ U32 const maxRep = curr - windowLow;
+ if (offset_2 > maxRep) offsetSaved = offset_2, offset_2 = 0;
+ if (offset_1 > maxRep) offsetSaved = offset_1, offset_1 = 0;
+ }
+ if (dictMode == ZSTD_dictMatchState) {
+ /* dictMatchState repCode checks don't currently handle repCode == 0
+ * disabling. */
+ assert(offset_1 <= dictAndPrefixLength);
+ assert(offset_2 <= dictAndPrefixLength);
+ }
+
+ /* Main Search Loop */
+ while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */
+ size_t mLength;
+ U32 offset;
+ size_t const h2 = ZSTD_hashPtr(ip, hBitsL, 8);
+ size_t const h = ZSTD_hashPtr(ip, hBitsS, mls);
+ size_t const dictHL = ZSTD_hashPtr(ip, dictHBitsL, 8);
+ size_t const dictHS = ZSTD_hashPtr(ip, dictHBitsS, mls);
+ U32 const curr = (U32)(ip-base);
+ U32 const matchIndexL = hashLong[h2];
+ U32 matchIndexS = hashSmall[h];
+ const BYTE* matchLong = base + matchIndexL;
+ const BYTE* match = base + matchIndexS;
+ const U32 repIndex = curr + 1 - offset_1;
+ const BYTE* repMatch = (dictMode == ZSTD_dictMatchState
+ && repIndex < prefixLowestIndex) ?
+ dictBase + (repIndex - dictIndexDelta) :
+ base + repIndex;
+ hashLong[h2] = hashSmall[h] = curr; /* update hash tables */
+
+ /* check dictMatchState repcode */
+ if (dictMode == ZSTD_dictMatchState
+ && ((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */)
+ && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) {
+ const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend;
+ mLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4;
+ ip++;
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, 0, mLength-MINMATCH);
+ goto _match_stored;
+ }
+
+ /* check noDict repcode */
+ if ( dictMode == ZSTD_noDict
+ && ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1)))) {
+ mLength = ZSTD_count(ip+1+4, ip+1+4-offset_1, iend) + 4;
+ ip++;
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, 0, mLength-MINMATCH);
+ goto _match_stored;
+ }
+
+ if (matchIndexL > prefixLowestIndex) {
+ /* check prefix long match */
+ if (MEM_read64(matchLong) == MEM_read64(ip)) {
+ mLength = ZSTD_count(ip+8, matchLong+8, iend) + 8;
+ offset = (U32)(ip-matchLong);
+ while (((ip>anchor) & (matchLong>prefixLowest)) && (ip[-1] == matchLong[-1])) { ip--; matchLong--; mLength++; } /* catch up */
+ goto _match_found;
+ }
+ } else if (dictMode == ZSTD_dictMatchState) {
+ /* check dictMatchState long match */
+ U32 const dictMatchIndexL = dictHashLong[dictHL];
+ const BYTE* dictMatchL = dictBase + dictMatchIndexL;
+ assert(dictMatchL < dictEnd);
+
+ if (dictMatchL > dictStart && MEM_read64(dictMatchL) == MEM_read64(ip)) {
+ mLength = ZSTD_count_2segments(ip+8, dictMatchL+8, iend, dictEnd, prefixLowest) + 8;
+ offset = (U32)(curr - dictMatchIndexL - dictIndexDelta);
+ while (((ip>anchor) & (dictMatchL>dictStart)) && (ip[-1] == dictMatchL[-1])) { ip--; dictMatchL--; mLength++; } /* catch up */
+ goto _match_found;
+ } }
+
+ if (matchIndexS > prefixLowestIndex) {
+ /* check prefix short match */
+ if (MEM_read32(match) == MEM_read32(ip)) {
+ goto _search_next_long;
+ }
+ } else if (dictMode == ZSTD_dictMatchState) {
+ /* check dictMatchState short match */
+ U32 const dictMatchIndexS = dictHashSmall[dictHS];
+ match = dictBase + dictMatchIndexS;
+ matchIndexS = dictMatchIndexS + dictIndexDelta;
+
+ if (match > dictStart && MEM_read32(match) == MEM_read32(ip)) {
+ goto _search_next_long;
+ } }
+
+ ip += ((ip-anchor) >> kSearchStrength) + 1;
+#if defined(__aarch64__)
+ PREFETCH_L1(ip+256);
+#endif
+ continue;
+
+_search_next_long:
+
+ { size_t const hl3 = ZSTD_hashPtr(ip+1, hBitsL, 8);
+ size_t const dictHLNext = ZSTD_hashPtr(ip+1, dictHBitsL, 8);
+ U32 const matchIndexL3 = hashLong[hl3];
+ const BYTE* matchL3 = base + matchIndexL3;
+ hashLong[hl3] = curr + 1;
+
+ /* check prefix long +1 match */
+ if (matchIndexL3 > prefixLowestIndex) {
+ if (MEM_read64(matchL3) == MEM_read64(ip+1)) {
+ mLength = ZSTD_count(ip+9, matchL3+8, iend) + 8;
+ ip++;
+ offset = (U32)(ip-matchL3);
+ while (((ip>anchor) & (matchL3>prefixLowest)) && (ip[-1] == matchL3[-1])) { ip--; matchL3--; mLength++; } /* catch up */
+ goto _match_found;
+ }
+ } else if (dictMode == ZSTD_dictMatchState) {
+ /* check dict long +1 match */
+ U32 const dictMatchIndexL3 = dictHashLong[dictHLNext];
+ const BYTE* dictMatchL3 = dictBase + dictMatchIndexL3;
+ assert(dictMatchL3 < dictEnd);
+ if (dictMatchL3 > dictStart && MEM_read64(dictMatchL3) == MEM_read64(ip+1)) {
+ mLength = ZSTD_count_2segments(ip+1+8, dictMatchL3+8, iend, dictEnd, prefixLowest) + 8;
+ ip++;
+ offset = (U32)(curr + 1 - dictMatchIndexL3 - dictIndexDelta);
+ while (((ip>anchor) & (dictMatchL3>dictStart)) && (ip[-1] == dictMatchL3[-1])) { ip--; dictMatchL3--; mLength++; } /* catch up */
+ goto _match_found;
+ } } }
+
+ /* if no long +1 match, explore the short match we found */
+ if (dictMode == ZSTD_dictMatchState && matchIndexS < prefixLowestIndex) {
+ mLength = ZSTD_count_2segments(ip+4, match+4, iend, dictEnd, prefixLowest) + 4;
+ offset = (U32)(curr - matchIndexS);
+ while (((ip>anchor) & (match>dictStart)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
+ } else {
+ mLength = ZSTD_count(ip+4, match+4, iend) + 4;
+ offset = (U32)(ip - match);
+ while (((ip>anchor) & (match>prefixLowest)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
+ }
+
+_match_found:
+ offset_2 = offset_1;
+ offset_1 = offset;
+
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
+
+_match_stored:
+ /* match found */
+ ip += mLength;
+ anchor = ip;
+
+ if (ip <= ilimit) {
+ /* Complementary insertion */
+ /* done after iLimit test, as candidates could be > iend-8 */
+ { U32 const indexToInsert = curr+2;
+ hashLong[ZSTD_hashPtr(base+indexToInsert, hBitsL, 8)] = indexToInsert;
+ hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base);
+ hashSmall[ZSTD_hashPtr(base+indexToInsert, hBitsS, mls)] = indexToInsert;
+ hashSmall[ZSTD_hashPtr(ip-1, hBitsS, mls)] = (U32)(ip-1-base);
+ }
+
+ /* check immediate repcode */
+ if (dictMode == ZSTD_dictMatchState) {
+ while (ip <= ilimit) {
+ U32 const current2 = (U32)(ip-base);
+ U32 const repIndex2 = current2 - offset_2;
+ const BYTE* repMatch2 = dictMode == ZSTD_dictMatchState
+ && repIndex2 < prefixLowestIndex ?
+ dictBase + repIndex2 - dictIndexDelta :
+ base + repIndex2;
+ if ( ((U32)((prefixLowestIndex-1) - (U32)repIndex2) >= 3 /* intentional overflow */)
+ && (MEM_read32(repMatch2) == MEM_read32(ip)) ) {
+ const BYTE* const repEnd2 = repIndex2 < prefixLowestIndex ? dictEnd : iend;
+ size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixLowest) + 4;
+ U32 tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */
+ ZSTD_storeSeq(seqStore, 0, anchor, iend, 0, repLength2-MINMATCH);
+ hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = current2;
+ hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = current2;
+ ip += repLength2;
+ anchor = ip;
+ continue;
+ }
+ break;
+ } }
+
+ if (dictMode == ZSTD_noDict) {
+ while ( (ip <= ilimit)
+ && ( (offset_2>0)
+ & (MEM_read32(ip) == MEM_read32(ip - offset_2)) )) {
+ /* store sequence */
+ size_t const rLength = ZSTD_count(ip+4, ip+4-offset_2, iend) + 4;
+ U32 const tmpOff = offset_2; offset_2 = offset_1; offset_1 = tmpOff; /* swap offset_2 <=> offset_1 */
+ hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip-base);
+ hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip-base);
+ ZSTD_storeSeq(seqStore, 0, anchor, iend, 0, rLength-MINMATCH);
+ ip += rLength;
+ anchor = ip;
+ continue; /* faster when present ... (?) */
+ } } }
+ } /* while (ip < ilimit) */
+
+ /* save reps for next block */
+ rep[0] = offset_1 ? offset_1 : offsetSaved;
+ rep[1] = offset_2 ? offset_2 : offsetSaved;
+
+ /* Return the last literals size */
+ return (size_t)(iend - anchor);
+}
+
+
+size_t ZSTD_compressBlock_doubleFast(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize)
+{
+ const U32 mls = ms->cParams.minMatch;
+ switch(mls)
+ {
+ default: /* includes case 3 */
+ case 4 :
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 4, ZSTD_noDict);
+ case 5 :
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 5, ZSTD_noDict);
+ case 6 :
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 6, ZSTD_noDict);
+ case 7 :
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 7, ZSTD_noDict);
+ }
+}
+
+
+size_t ZSTD_compressBlock_doubleFast_dictMatchState(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize)
+{
+ const U32 mls = ms->cParams.minMatch;
+ switch(mls)
+ {
+ default: /* includes case 3 */
+ case 4 :
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 4, ZSTD_dictMatchState);
+ case 5 :
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 5, ZSTD_dictMatchState);
+ case 6 :
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 6, ZSTD_dictMatchState);
+ case 7 :
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 7, ZSTD_dictMatchState);
+ }
+}
+
+
+static size_t ZSTD_compressBlock_doubleFast_extDict_generic(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize,
+ U32 const mls /* template */)
+{
+ ZSTD_compressionParameters const* cParams = &ms->cParams;
+ U32* const hashLong = ms->hashTable;
+ U32 const hBitsL = cParams->hashLog;
+ U32* const hashSmall = ms->chainTable;
+ U32 const hBitsS = cParams->chainLog;
+ 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 U32 endIndex = (U32)((size_t)(istart - base) + srcSize);
+ const U32 lowLimit = ZSTD_getLowestMatchIndex(ms, endIndex, cParams->windowLog);
+ const U32 dictStartIndex = lowLimit;
+ const U32 dictLimit = ms->window.dictLimit;
+ const U32 prefixStartIndex = (dictLimit > lowLimit) ? dictLimit : lowLimit;
+ const BYTE* const prefixStart = base + prefixStartIndex;
+ const BYTE* const dictBase = ms->window.dictBase;
+ const BYTE* const dictStart = dictBase + dictStartIndex;
+ const BYTE* const dictEnd = dictBase + prefixStartIndex;
+ U32 offset_1=rep[0], offset_2=rep[1];
+
+ DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_extDict_generic (srcSize=%zu)", srcSize);
+
+ /* if extDict is invalidated due to maxDistance, switch to "regular" variant */
+ if (prefixStartIndex == dictStartIndex)
+ return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, mls, ZSTD_noDict);
+
+ /* Search Loop */
+ while (ip < ilimit) { /* < instead of <=, because (ip+1) */
+ const size_t hSmall = ZSTD_hashPtr(ip, hBitsS, mls);
+ const U32 matchIndex = hashSmall[hSmall];
+ const BYTE* const matchBase = matchIndex < prefixStartIndex ? dictBase : base;
+ const BYTE* match = matchBase + matchIndex;
+
+ const size_t hLong = ZSTD_hashPtr(ip, hBitsL, 8);
+ const U32 matchLongIndex = hashLong[hLong];
+ const BYTE* const matchLongBase = matchLongIndex < prefixStartIndex ? dictBase : base;
+ const BYTE* matchLong = matchLongBase + matchLongIndex;
+
+ const U32 curr = (U32)(ip-base);
+ const U32 repIndex = curr + 1 - offset_1; /* offset_1 expected <= curr +1 */
+ const BYTE* const repBase = repIndex < prefixStartIndex ? dictBase : base;
+ const BYTE* const repMatch = repBase + repIndex;
+ size_t mLength;
+ hashSmall[hSmall] = hashLong[hLong] = curr; /* update hash table */
+
+ if ((((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow : ensure repIndex doesn't overlap dict + prefix */
+ & (repIndex > dictStartIndex))
+ && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) {
+ const BYTE* repMatchEnd = repIndex < prefixStartIndex ? dictEnd : iend;
+ mLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixStart) + 4;
+ ip++;
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, 0, mLength-MINMATCH);
+ } else {
+ if ((matchLongIndex > dictStartIndex) && (MEM_read64(matchLong) == MEM_read64(ip))) {
+ const BYTE* const matchEnd = matchLongIndex < prefixStartIndex ? dictEnd : iend;
+ const BYTE* const lowMatchPtr = matchLongIndex < prefixStartIndex ? dictStart : prefixStart;
+ U32 offset;
+ mLength = ZSTD_count_2segments(ip+8, matchLong+8, iend, matchEnd, prefixStart) + 8;
+ offset = curr - matchLongIndex;
+ while (((ip>anchor) & (matchLong>lowMatchPtr)) && (ip[-1] == matchLong[-1])) { ip--; matchLong--; mLength++; } /* catch up */
+ offset_2 = offset_1;
+ offset_1 = offset;
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
+
+ } else if ((matchIndex > dictStartIndex) && (MEM_read32(match) == MEM_read32(ip))) {
+ size_t const h3 = ZSTD_hashPtr(ip+1, hBitsL, 8);
+ U32 const matchIndex3 = hashLong[h3];
+ const BYTE* const match3Base = matchIndex3 < prefixStartIndex ? dictBase : base;
+ const BYTE* match3 = match3Base + matchIndex3;
+ U32 offset;
+ hashLong[h3] = curr + 1;
+ if ( (matchIndex3 > dictStartIndex) && (MEM_read64(match3) == MEM_read64(ip+1)) ) {
+ const BYTE* const matchEnd = matchIndex3 < prefixStartIndex ? dictEnd : iend;
+ const BYTE* const lowMatchPtr = matchIndex3 < prefixStartIndex ? dictStart : prefixStart;
+ mLength = ZSTD_count_2segments(ip+9, match3+8, iend, matchEnd, prefixStart) + 8;
+ ip++;
+ offset = curr+1 - matchIndex3;
+ while (((ip>anchor) & (match3>lowMatchPtr)) && (ip[-1] == match3[-1])) { ip--; match3--; mLength++; } /* catch up */
+ } else {
+ const BYTE* const matchEnd = matchIndex < prefixStartIndex ? dictEnd : iend;
+ const BYTE* const lowMatchPtr = matchIndex < prefixStartIndex ? dictStart : prefixStart;
+ mLength = ZSTD_count_2segments(ip+4, match+4, iend, matchEnd, prefixStart) + 4;
+ offset = curr - matchIndex;
+ while (((ip>anchor) & (match>lowMatchPtr)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
+ }
+ offset_2 = offset_1;
+ offset_1 = offset;
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
+
+ } else {
+ ip += ((ip-anchor) >> kSearchStrength) + 1;
+ continue;
+ } }
+
+ /* move to next sequence start */
+ ip += mLength;
+ anchor = ip;
+
+ if (ip <= ilimit) {
+ /* Complementary insertion */
+ /* done after iLimit test, as candidates could be > iend-8 */
+ { U32 const indexToInsert = curr+2;
+ hashLong[ZSTD_hashPtr(base+indexToInsert, hBitsL, 8)] = indexToInsert;
+ hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base);
+ hashSmall[ZSTD_hashPtr(base+indexToInsert, hBitsS, mls)] = indexToInsert;
+ hashSmall[ZSTD_hashPtr(ip-1, hBitsS, mls)] = (U32)(ip-1-base);
+ }
+
+ /* check immediate repcode */
+ while (ip <= ilimit) {
+ U32 const current2 = (U32)(ip-base);
+ U32 const repIndex2 = current2 - offset_2;
+ const BYTE* repMatch2 = repIndex2 < prefixStartIndex ? dictBase + repIndex2 : base + repIndex2;
+ if ( (((U32)((prefixStartIndex-1) - repIndex2) >= 3) /* intentional overflow : ensure repIndex2 doesn't overlap dict + prefix */
+ & (repIndex2 > dictStartIndex))
+ && (MEM_read32(repMatch2) == MEM_read32(ip)) ) {
+ const BYTE* const repEnd2 = repIndex2 < prefixStartIndex ? dictEnd : iend;
+ size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixStart) + 4;
+ U32 const tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */
+ ZSTD_storeSeq(seqStore, 0, anchor, iend, 0, repLength2-MINMATCH);
+ hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = current2;
+ hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = current2;
+ ip += repLength2;
+ anchor = ip;
+ continue;
+ }
+ break;
+ } } }
+
+ /* save reps for next block */
+ rep[0] = offset_1;
+ rep[1] = offset_2;
+
+ /* Return the last literals size */
+ return (size_t)(iend - anchor);
+}
+
+
+size_t ZSTD_compressBlock_doubleFast_extDict(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize)
+{
+ U32 const mls = ms->cParams.minMatch;
+ switch(mls)
+ {
+ default: /* includes case 3 */
+ case 4 :
+ return ZSTD_compressBlock_doubleFast_extDict_generic(ms, seqStore, rep, src, srcSize, 4);
+ case 5 :
+ return ZSTD_compressBlock_doubleFast_extDict_generic(ms, seqStore, rep, src, srcSize, 5);
+ case 6 :
+ return ZSTD_compressBlock_doubleFast_extDict_generic(ms, seqStore, rep, src, srcSize, 6);
+ case 7 :
+ return ZSTD_compressBlock_doubleFast_extDict_generic(ms, seqStore, rep, src, srcSize, 7);
+ }
+}
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-16 08:32:44 +0000