text: /*
   * Copyright (c) 2016-present, 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 current = (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] = current + i;
        if (i == 0 || hashLarge[lgHash] == 0)
          hashLarge[lgHash] = current + 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 prefixLowestIndex = ms->window.dictLimit;
    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);
  
    assert(dictMode == ZSTD_noDict || dictMode == ZSTD_dictMatchState);
  
    /* init */
    ip += (dictAndPrefixLength == 0);
    if (dictMode == ZSTD_noDict) {
      U32 const maxRep = (U32)(ip - prefixLowest);
      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 current = (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 = current + 1 - offset_1;
      const BYTE* repMatch = (dictMode == ZSTD_dictMatchState && repIndex < prefixLowestIndex)
                                 ? dictBase + (repIndex - dictIndexDelta)
                                 : base + repIndex;
      hashLong[h2] = hashSmall[h] = current; /* 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, ip - anchor, anchor, 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, ip - anchor, anchor, 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)(current - 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;
      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] = current + 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)(current + 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)(current - 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 */
      }
  
      /* fall-through */
  
    _match_found:
      offset_2 = offset_1;
      offset_1 = offset;
  
      ZSTD_storeSeq(seqStore, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH);
  
    _match_stored:
      /* match found */
      ip += mLength;
      anchor = ip;
  
      if (ip <= ilimit) {
        /* Fill Table */
        hashLong[ZSTD_hashPtr(base + current + 2, hBitsL, 8)] = hashSmall[ZSTD_hashPtr(base + current + 2, hBitsS, mls)] =
            current + 2; /* here because current+2 could be > iend-8 */
        hashLong[ZSTD_hashPtr(ip - 2, hBitsL, 8)] = hashSmall[ZSTD_hashPtr(ip - 2, hBitsS, mls)] = (U32)(ip - 2 - 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 - dictIndexDelta + repIndex2
                                        : 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, 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, 0, rLength - MINMATCH);
            ip += rLength;
            anchor = ip;
            continue; /* faster when present ... (?) */
          }
        }
      }
    }
  
    /* 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 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 U32 prefixStartIndex = ms->window.dictLimit;
    const BYTE* const base = ms->window.base;
    const BYTE* const prefixStart = base + prefixStartIndex;
    const U32 dictStartIndex = ms->window.lowLimit;
    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);
  
    /* 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 current = (U32)(ip - base);
      const U32 repIndex = current + 1 - offset_1; /* offset_1 expected <= current +1 */
      const BYTE* const repBase = repIndex < prefixStartIndex ? dictBase : base;
      const BYTE* const repMatch = repBase + repIndex;
      size_t mLength;
      hashSmall[hSmall] = hashLong[hLong] = current; /* 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, ip - anchor, anchor, 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 = current - 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, ip - anchor, anchor, 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] = current + 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 = current + 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 = current - 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, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH);
  
        } else {
          ip += ((ip - anchor) >> kSearchStrength) + 1;
          continue;
        }
      }
  
      /* found a match : store it */
      ip += mLength;
      anchor = ip;
  
      if (ip <= ilimit) {
        /* Fill Table */
        hashSmall[ZSTD_hashPtr(base + current + 2, hBitsS, mls)] = current + 2;
        hashLong[ZSTD_hashPtr(base + current + 2, hBitsL, 8)] = current + 2;
        hashSmall[ZSTD_hashPtr(ip - 2, hBitsS, mls)] = (U32)(ip - 2 - base);
        hashLong[ZSTD_hashPtr(ip - 2, hBitsL, 8)] = (U32)(ip - 2 - 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, 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 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);
    }
  }
  