Upgrading lzma_sdk to version 9.20.

third_party/lzma_sdk/C/LzFindMt.c

+/* LzFindMt.c -- multithreaded Match finder for LZ algorithms
+2009-09-20 : Igor Pavlov : Public domain */
+
+#include "LzHash.h"
+
+#include "LzFindMt.h"
+
+void MtSync_Construct(CMtSync *p)
+{
+  p->wasCreated = False;
+  p->csWasInitialized = False;
+  p->csWasEntered = False;
+  Thread_Construct(&p->thread);
+  Event_Construct(&p->canStart);
+  Event_Construct(&p->wasStarted);
+  Event_Construct(&p->wasStopped);
+  Semaphore_Construct(&p->freeSemaphore);
+  Semaphore_Construct(&p->filledSemaphore);
+}
+
+void MtSync_GetNextBlock(CMtSync *p)
+{
+  if (p->needStart)
+  {
+    p->numProcessedBlocks = 1;
+    p->needStart = False;
+    p->stopWriting = False;
+    p->exit = False;
+    Event_Reset(&p->wasStarted);
+    Event_Reset(&p->wasStopped);
+
+    Event_Set(&p->canStart);
+    Event_Wait(&p->wasStarted);
+  }
+  else
+  {
+    CriticalSection_Leave(&p->cs);
+    p->csWasEntered = False;
+    p->numProcessedBlocks++;
+    Semaphore_Release1(&p->freeSemaphore);
+  }
+  Semaphore_Wait(&p->filledSemaphore);
+  CriticalSection_Enter(&p->cs);
+  p->csWasEntered = True;
+}
+
+/* MtSync_StopWriting must be called if Writing was started */
+
+void MtSync_StopWriting(CMtSync *p)
+{
+  UInt32 myNumBlocks = p->numProcessedBlocks;
+  if (!Thread_WasCreated(&p->thread) || p->needStart)
+    return;
+  p->stopWriting = True;
+  if (p->csWasEntered)
+  {
+    CriticalSection_Leave(&p->cs);
+    p->csWasEntered = False;
+  }
+  Semaphore_Release1(&p->freeSemaphore);
+ 
+  Event_Wait(&p->wasStopped);
+
+  while (myNumBlocks++ != p->numProcessedBlocks)
+  {
+    Semaphore_Wait(&p->filledSemaphore);
+    Semaphore_Release1(&p->freeSemaphore);
+  }
+  p->needStart = True;
+}
+
+void MtSync_Destruct(CMtSync *p)
+{
+  if (Thread_WasCreated(&p->thread))
+  {
+    MtSync_StopWriting(p);
+    p->exit = True;
+    if (p->needStart)
+      Event_Set(&p->canStart);
+    Thread_Wait(&p->thread);
+    Thread_Close(&p->thread);
+  }
+  if (p->csWasInitialized)
+  {
+    CriticalSection_Delete(&p->cs);
+    p->csWasInitialized = False;
+  }
+
+  Event_Close(&p->canStart);
+  Event_Close(&p->wasStarted);
+  Event_Close(&p->wasStopped);
+  Semaphore_Close(&p->freeSemaphore);
+  Semaphore_Close(&p->filledSemaphore);
+
+  p->wasCreated = False;
+}
+
+#define RINOK_THREAD(x) { if ((x) != 0) return SZ_ERROR_THREAD; }
+
+static SRes MtSync_Create2(CMtSync *p, unsigned (MY_STD_CALL *startAddress)(void *), void *obj, UInt32 numBlocks)
+{
+  if (p->wasCreated)
+    return SZ_OK;
+
+  RINOK_THREAD(CriticalSection_Init(&p->cs));
+  p->csWasInitialized = True;
+
+  RINOK_THREAD(AutoResetEvent_CreateNotSignaled(&p->canStart));
+  RINOK_THREAD(AutoResetEvent_CreateNotSignaled(&p->wasStarted));
+  RINOK_THREAD(AutoResetEvent_CreateNotSignaled(&p->wasStopped));
+  
+  RINOK_THREAD(Semaphore_Create(&p->freeSemaphore, numBlocks, numBlocks));
+  RINOK_THREAD(Semaphore_Create(&p->filledSemaphore, 0, numBlocks));
+
+  p->needStart = True;
+  
+  RINOK_THREAD(Thread_Create(&p->thread, startAddress, obj));
+  p->wasCreated = True;
+  return SZ_OK;
+}
+
+static SRes MtSync_Create(CMtSync *p, unsigned (MY_STD_CALL *startAddress)(void *), void *obj, UInt32 numBlocks)
+{
+  SRes res = MtSync_Create2(p, startAddress, obj, numBlocks);
+  if (res != SZ_OK)
+    MtSync_Destruct(p);
+  return res;
+}
+
+void MtSync_Init(CMtSync *p) { p->needStart = True; }
+
+#define kMtMaxValForNormalize 0xFFFFFFFF
+
+#define DEF_GetHeads2(name, v, action) \
+static void GetHeads ## name(const Byte *p, UInt32 pos, \
+UInt32 *hash, UInt32 hashMask, UInt32 *heads, UInt32 numHeads, const UInt32 *crc) \
+{ action; for (; numHeads != 0; numHeads--) { \
+const UInt32 value = (v); p++; *heads++ = pos - hash[value]; hash[value] = pos++;  } }
+
+#define DEF_GetHeads(name, v) DEF_GetHeads2(name, v, ;)
+
+DEF_GetHeads2(2,  (p[0] | ((UInt32)p[1] << 8)), hashMask = hashMask; crc = crc; )
+DEF_GetHeads(3,  (crc[p[0]] ^ p[1] ^ ((UInt32)p[2] << 8)) & hashMask)
+DEF_GetHeads(4,  (crc[p[0]] ^ p[1] ^ ((UInt32)p[2] << 8) ^ (crc[p[3]] << 5)) & hashMask)
+DEF_GetHeads(4b, (crc[p[0]] ^ p[1] ^ ((UInt32)p[2] << 8) ^ ((UInt32)p[3] << 16)) & hashMask)
+/* DEF_GetHeads(5,  (crc[p[0]] ^ p[1] ^ ((UInt32)p[2] << 8) ^ (crc[p[3]] << 5) ^ (crc[p[4]] << 3)) & hashMask) */
+
+void HashThreadFunc(CMatchFinderMt *mt)
+{
+  CMtSync *p = &mt->hashSync;
+  for (;;)
+  {
+    UInt32 numProcessedBlocks = 0;
+    Event_Wait(&p->canStart);
+    Event_Set(&p->wasStarted);
+    for (;;)
+    {
+      if (p->exit)
+        return;
+      if (p->stopWriting)
+      {
+        p->numProcessedBlocks = numProcessedBlocks;
+        Event_Set(&p->wasStopped);
+        break;
+      }
+
+      {
+        CMatchFinder *mf = mt->MatchFinder;
+        if (MatchFinder_NeedMove(mf))
+        {
+          CriticalSection_Enter(&mt->btSync.cs);
+          CriticalSection_Enter(&mt->hashSync.cs);
+          {
+            const Byte *beforePtr = MatchFinder_GetPointerToCurrentPos(mf);
+            const Byte *afterPtr;
+            MatchFinder_MoveBlock(mf);
+            afterPtr = MatchFinder_GetPointerToCurrentPos(mf);
+            mt->pointerToCurPos -= beforePtr - afterPtr;
+            mt->buffer -= beforePtr - afterPtr;
+          }
+          CriticalSection_Leave(&mt->btSync.cs);
+          CriticalSection_Leave(&mt->hashSync.cs);
+          continue;
+        }
+
+        Semaphore_Wait(&p->freeSemaphore);
+
+        MatchFinder_ReadIfRequired(mf);
+        if (mf->pos > (kMtMaxValForNormalize - kMtHashBlockSize))
+        {
+          UInt32 subValue = (mf->pos - mf->historySize - 1);
+          MatchFinder_ReduceOffsets(mf, subValue);
+          MatchFinder_Normalize3(subValue, mf->hash + mf->fixedHashSize, mf->hashMask + 1);
+        }
+        {
+          UInt32 *heads = mt->hashBuf + ((numProcessedBlocks++) & kMtHashNumBlocksMask) * kMtHashBlockSize;
+          UInt32 num = mf->streamPos - mf->pos;
+          heads[0] = 2;
+          heads[1] = num;
+          if (num >= mf->numHashBytes)
+          {
+            num = num - mf->numHashBytes + 1;
+            if (num > kMtHashBlockSize - 2)
+              num = kMtHashBlockSize - 2;
+            mt->GetHeadsFunc(mf->buffer, mf->pos, mf->hash + mf->fixedHashSize, mf->hashMask, heads + 2, num, mf->crc);
+            heads[0] += num;
+          }
+          mf->pos += num;
+          mf->buffer += num;
+        }
+      }
+
+      Semaphore_Release1(&p->filledSemaphore);
+    }
+  }
+}
+
+void MatchFinderMt_GetNextBlock_Hash(CMatchFinderMt *p)
+{
+  MtSync_GetNextBlock(&p->hashSync);
+  p->hashBufPosLimit = p->hashBufPos = ((p->hashSync.numProcessedBlocks - 1) & kMtHashNumBlocksMask) * kMtHashBlockSize;
+  p->hashBufPosLimit += p->hashBuf[p->hashBufPos++];
+  p->hashNumAvail = p->hashBuf[p->hashBufPos++];
+}
+
+#define kEmptyHashValue 0
+
+/* #define MFMT_GM_INLINE */
+
+#ifdef MFMT_GM_INLINE
+
+#define NO_INLINE MY_FAST_CALL
+
+Int32 NO_INLINE GetMatchesSpecN(UInt32 lenLimit, UInt32 pos, const Byte *cur, CLzRef *son,
+    UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 _cutValue,
+    UInt32 *_distances, UInt32 _maxLen, const UInt32 *hash, Int32 limit, UInt32 size, UInt32 *posRes)
+{
+  do
+  {
+  UInt32 *distances = _distances + 1;
+  UInt32 curMatch = pos - *hash++;
+
+  CLzRef *ptr0 = son + (_cyclicBufferPos << 1) + 1;
+  CLzRef *ptr1 = son + (_cyclicBufferPos << 1);
+  UInt32 len0 = 0, len1 = 0;
+  UInt32 cutValue = _cutValue;
+  UInt32 maxLen = _maxLen;
+  for (;;)
+  {
+    UInt32 delta = pos - curMatch;
+    if (cutValue-- == 0 || delta >= _cyclicBufferSize)
+    {
+      *ptr0 = *ptr1 = kEmptyHashValue;
+      break;
+    }
+    {
+      CLzRef *pair = son + ((_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)) << 1);
+      const Byte *pb = cur - delta;
+      UInt32 len = (len0 < len1 ? len0 : len1);
+      if (pb[len] == cur[len])
+      {
+        if (++len != lenLimit && pb[len] == cur[len])
+          while (++len != lenLimit)
+            if (pb[len] != cur[len])
+              break;
+        if (maxLen < len)
+        {
+          *distances++ = maxLen = len;
+          *distances++ = delta - 1;
+          if (len == lenLimit)
+          {
+            *ptr1 = pair[0];
+            *ptr0 = pair[1];
+            break;
+          }
+        }
+      }
+      if (pb[len] < cur[len])
+      {
+        *ptr1 = curMatch;
+        ptr1 = pair + 1;
+        curMatch = *ptr1;
+        len1 = len;
+      }
+      else
+      {
+        *ptr0 = curMatch;
+        ptr0 = pair;
+        curMatch = *ptr0;
+        len0 = len;
+      }
+    }
+  }
+  pos++;
+  _cyclicBufferPos++;
+  cur++;
+  {
+    UInt32 num = (UInt32)(distances - _distances);
+    *_distances = num - 1;
+    _distances += num;
+    limit -= num;
+  }
+  }
+  while (limit > 0 && --size != 0);
+  *posRes = pos;
+  return limit;
+}
+
+#endif
+
+void BtGetMatches(CMatchFinderMt *p, UInt32 *distances)
+{
+  UInt32 numProcessed = 0;
+  UInt32 curPos = 2;
+  UInt32 limit = kMtBtBlockSize - (p->matchMaxLen * 2);
+  distances[1] = p->hashNumAvail;
+  while (curPos < limit)
+  {
+    if (p->hashBufPos == p->hashBufPosLimit)
+    {
+      MatchFinderMt_GetNextBlock_Hash(p);
+      distances[1] = numProcessed + p->hashNumAvail;
+      if (p->hashNumAvail >= p->numHashBytes)
+        continue;
+      for (; p->hashNumAvail != 0; p->hashNumAvail--)
+        distances[curPos++] = 0;
+      break;
+    }
+    {
+      UInt32 size = p->hashBufPosLimit - p->hashBufPos;
+      UInt32 lenLimit = p->matchMaxLen;
+      UInt32 pos = p->pos;
+      UInt32 cyclicBufferPos = p->cyclicBufferPos;
+      if (lenLimit >= p->hashNumAvail)
+        lenLimit = p->hashNumAvail;
+      {
+        UInt32 size2 = p->hashNumAvail - lenLimit + 1;
+        if (size2 < size)
+          size = size2;
+        size2 = p->cyclicBufferSize - cyclicBufferPos;
+        if (size2 < size)
+          size = size2;
+      }
+      #ifndef MFMT_GM_INLINE
+      while (curPos < limit && size-- != 0)
+      {
+        UInt32 *startDistances = distances + curPos;
+        UInt32 num = (UInt32)(GetMatchesSpec1(lenLimit, pos - p->hashBuf[p->hashBufPos++],
+          pos, p->buffer, p->son, cyclicBufferPos, p->cyclicBufferSize, p->cutValue,
+          startDistances + 1, p->numHashBytes - 1) - startDistances);
+        *startDistances = num - 1;
+        curPos += num;
+        cyclicBufferPos++;
+        pos++;
+        p->buffer++;
+      }
+      #else
+      {
+        UInt32 posRes;
+        curPos = limit - GetMatchesSpecN(lenLimit, pos, p->buffer, p->son, cyclicBufferPos, p->cyclicBufferSize, p->cutValue,
+          distances + curPos, p->numHashBytes - 1, p->hashBuf + p->hashBufPos, (Int32)(limit - curPos) , size, &posRes);
+        p->hashBufPos += posRes - pos;
+        cyclicBufferPos += posRes - pos;
+        p->buffer += posRes - pos;
+        pos = posRes;
+      }
+      #endif
+
+      numProcessed += pos - p->pos;
+      p->hashNumAvail -= pos - p->pos;
+      p->pos = pos;
+      if (cyclicBufferPos == p->cyclicBufferSize)
+        cyclicBufferPos = 0;
+      p->cyclicBufferPos = cyclicBufferPos;
+    }
+  }
+  distances[0] = curPos;
+}
+
+void BtFillBlock(CMatchFinderMt *p, UInt32 globalBlockIndex)
+{
+  CMtSync *sync = &p->hashSync;
+  if (!sync->needStart)
+  {
+    CriticalSection_Enter(&sync->cs);
+    sync->csWasEntered = True;
+  }
+  
+  BtGetMatches(p, p->btBuf + (globalBlockIndex & kMtBtNumBlocksMask) * kMtBtBlockSize);
+
+  if (p->pos > kMtMaxValForNormalize - kMtBtBlockSize)
+  {
+    UInt32 subValue = p->pos - p->cyclicBufferSize;
+    MatchFinder_Normalize3(subValue, p->son, p->cyclicBufferSize * 2);
+    p->pos -= subValue;
+  }
+
+  if (!sync->needStart)
+  {
+    CriticalSection_Leave(&sync->cs);
+    sync->csWasEntered = False;
+  }
+}
+
+void BtThreadFunc(CMatchFinderMt *mt)
+{
+  CMtSync *p = &mt->btSync;
+  for (;;)
+  {
+    UInt32 blockIndex = 0;
+    Event_Wait(&p->canStart);
+    Event_Set(&p->wasStarted);
+    for (;;)
+    {
+      if (p->exit)
+        return;
+      if (p->stopWriting)
+      {
+        p->numProcessedBlocks = blockIndex;
+        MtSync_StopWriting(&mt->hashSync);
+        Event_Set(&p->wasStopped);
+        break;
+      }
+      Semaphore_Wait(&p->freeSemaphore);
+      BtFillBlock(mt, blockIndex++);
+      Semaphore_Release1(&p->filledSemaphore);
+    }
+  }
+}
+
+void MatchFinderMt_Construct(CMatchFinderMt *p)
+{
+  p->hashBuf = 0;
+  MtSync_Construct(&p->hashSync);
+  MtSync_Construct(&p->btSync);
+}
+
+void MatchFinderMt_FreeMem(CMatchFinderMt *p, ISzAlloc *alloc)
+{
+  alloc->Free(alloc, p->hashBuf);
+  p->hashBuf = 0;
+}
+
+void MatchFinderMt_Destruct(CMatchFinderMt *p, ISzAlloc *alloc)
+{
+  MtSync_Destruct(&p->hashSync);
+  MtSync_Destruct(&p->btSync);
+  MatchFinderMt_FreeMem(p, alloc);
+}
+
+#define kHashBufferSize (kMtHashBlockSize * kMtHashNumBlocks)
+#define kBtBufferSize (kMtBtBlockSize * kMtBtNumBlocks)
+
+static unsigned MY_STD_CALL HashThreadFunc2(void *p) { HashThreadFunc((CMatchFinderMt *)p);  return 0; }
+static unsigned MY_STD_CALL BtThreadFunc2(void *p)
+{
+  Byte allocaDummy[0x180];
+  int i = 0;
+  for (i = 0; i < 16; i++)
+    allocaDummy[i] = (Byte)i;
+  BtThreadFunc((CMatchFinderMt *)p);
+  return 0;
+}
+
+SRes MatchFinderMt_Create(CMatchFinderMt *p, UInt32 historySize, UInt32 keepAddBufferBefore,
+    UInt32 matchMaxLen, UInt32 keepAddBufferAfter, ISzAlloc *alloc)
+{
+  CMatchFinder *mf = p->MatchFinder;
+  p->historySize = historySize;
+  if (kMtBtBlockSize <= matchMaxLen * 4)
+    return SZ_ERROR_PARAM;
+  if (p->hashBuf == 0)
+  {
+    p->hashBuf = (UInt32 *)alloc->Alloc(alloc, (kHashBufferSize + kBtBufferSize) * sizeof(UInt32));
+    if (p->hashBuf == 0)
+      return SZ_ERROR_MEM;
+    p->btBuf = p->hashBuf + kHashBufferSize;
+  }
+  keepAddBufferBefore += (kHashBufferSize + kBtBufferSize);
+  keepAddBufferAfter += kMtHashBlockSize;
+  if (!MatchFinder_Create(mf, historySize, keepAddBufferBefore, matchMaxLen, keepAddBufferAfter, alloc))
+    return SZ_ERROR_MEM;
+
+  RINOK(MtSync_Create(&p->hashSync, HashThreadFunc2, p, kMtHashNumBlocks));
+  RINOK(MtSync_Create(&p->btSync, BtThreadFunc2, p, kMtBtNumBlocks));
+  return SZ_OK;
+}
+
+/* Call it after ReleaseStream / SetStream */
+void MatchFinderMt_Init(CMatchFinderMt *p)
+{
+  CMatchFinder *mf = p->MatchFinder;
+  p->btBufPos = p->btBufPosLimit = 0;
+  p->hashBufPos = p->hashBufPosLimit = 0;
+  MatchFinder_Init(mf);
+  p->pointerToCurPos = MatchFinder_GetPointerToCurrentPos(mf);
+  p->btNumAvailBytes = 0;
+  p->lzPos = p->historySize + 1;
+
+  p->hash = mf->hash;
+  p->fixedHashSize = mf->fixedHashSize;
+  p->crc = mf->crc;
+
+  p->son = mf->son;
+  p->matchMaxLen = mf->matchMaxLen;
+  p->numHashBytes = mf->numHashBytes;
+  p->pos = mf->pos;
+  p->buffer = mf->buffer;
+  p->cyclicBufferPos = mf->cyclicBufferPos;
+  p->cyclicBufferSize = mf->cyclicBufferSize;
+  p->cutValue = mf->cutValue;
+}
+
+/* ReleaseStream is required to finish multithreading */
+void MatchFinderMt_ReleaseStream(CMatchFinderMt *p)
+{
+  MtSync_StopWriting(&p->btSync);
+  /* p->MatchFinder->ReleaseStream(); */
+}
+
+void MatchFinderMt_Normalize(CMatchFinderMt *p)
+{
+  MatchFinder_Normalize3(p->lzPos - p->historySize - 1, p->hash, p->fixedHashSize);
+  p->lzPos = p->historySize + 1;
+}
+
+void MatchFinderMt_GetNextBlock_Bt(CMatchFinderMt *p)
+{
+  UInt32 blockIndex;
+  MtSync_GetNextBlock(&p->btSync);
+  blockIndex = ((p->btSync.numProcessedBlocks - 1) & kMtBtNumBlocksMask);
+  p->btBufPosLimit = p->btBufPos = blockIndex * kMtBtBlockSize;
+  p->btBufPosLimit += p->btBuf[p->btBufPos++];
+  p->btNumAvailBytes = p->btBuf[p->btBufPos++];
+  if (p->lzPos >= kMtMaxValForNormalize - kMtBtBlockSize)
+    MatchFinderMt_Normalize(p);
+}
+
+const Byte * MatchFinderMt_GetPointerToCurrentPos(CMatchFinderMt *p)
+{
+  return p->pointerToCurPos;
+}
+
+#define GET_NEXT_BLOCK_IF_REQUIRED if (p->btBufPos == p->btBufPosLimit) MatchFinderMt_GetNextBlock_Bt(p);
+
+UInt32 MatchFinderMt_GetNumAvailableBytes(CMatchFinderMt *p)
+{
+  GET_NEXT_BLOCK_IF_REQUIRED;
+  return p->btNumAvailBytes;
+}
+
+Byte MatchFinderMt_GetIndexByte(CMatchFinderMt *p, Int32 index)
+{
+  return p->pointerToCurPos[index];
+}
+
+UInt32 * MixMatches2(CMatchFinderMt *p, UInt32 matchMinPos, UInt32 *distances)
+{
+  UInt32 hash2Value, curMatch2;
+  UInt32 *hash = p->hash;
+  const Byte *cur = p->pointerToCurPos;
+  UInt32 lzPos = p->lzPos;
+  MT_HASH2_CALC
+      
+  curMatch2 = hash[hash2Value];
+  hash[hash2Value] = lzPos;
+
+  if (curMatch2 >= matchMinPos)
+    if (cur[(ptrdiff_t)curMatch2 - lzPos] == cur[0])
+    {
+      *distances++ = 2;
+      *distances++ = lzPos - curMatch2 - 1;
+    }
+  return distances;
+}
+
+UInt32 * MixMatches3(CMatchFinderMt *p, UInt32 matchMinPos, UInt32 *distances)
+{
+  UInt32 hash2Value, hash3Value, curMatch2, curMatch3;
+  UInt32 *hash = p->hash;
+  const Byte *cur = p->pointerToCurPos;
+  UInt32 lzPos = p->lzPos;
+  MT_HASH3_CALC
+
+  curMatch2 = hash[                hash2Value];
+  curMatch3 = hash[kFix3HashSize + hash3Value];
+  
+  hash[                hash2Value] =
+  hash[kFix3HashSize + hash3Value] =
+    lzPos;
+
+  if (curMatch2 >= matchMinPos && cur[(ptrdiff_t)curMatch2 - lzPos] == cur[0])
+  {
+    distances[1] = lzPos - curMatch2 - 1;
+    if (cur[(ptrdiff_t)curMatch2 - lzPos + 2] == cur[2])
+    {
+      distances[0] = 3;
+      return distances + 2;
+    }
+    distances[0] = 2;
+    distances += 2;
+  }
+  if (curMatch3 >= matchMinPos && cur[(ptrdiff_t)curMatch3 - lzPos] == cur[0])
+  {
+    *distances++ = 3;
+    *distances++ = lzPos - curMatch3 - 1;
+  }
+  return distances;
+}
+
+/*
+UInt32 *MixMatches4(CMatchFinderMt *p, UInt32 matchMinPos, UInt32 *distances)
+{
+  UInt32 hash2Value, hash3Value, hash4Value, curMatch2, curMatch3, curMatch4;
+  UInt32 *hash = p->hash;
+  const Byte *cur = p->pointerToCurPos;
+  UInt32 lzPos = p->lzPos;
+  MT_HASH4_CALC
+      
+  curMatch2 = hash[                hash2Value];
+  curMatch3 = hash[kFix3HashSize + hash3Value];
+  curMatch4 = hash[kFix4HashSize + hash4Value];
+  
+  hash[                hash2Value] =
+  hash[kFix3HashSize + hash3Value] =
+  hash[kFix4HashSize + hash4Value] =
+    lzPos;
+
+  if (curMatch2 >= matchMinPos && cur[(ptrdiff_t)curMatch2 - lzPos] == cur[0])
+  {
+    distances[1] = lzPos - curMatch2 - 1;
+    if (cur[(ptrdiff_t)curMatch2 - lzPos + 2] == cur[2])
+    {
+      distances[0] =  (cur[(ptrdiff_t)curMatch2 - lzPos + 3] == cur[3]) ? 4 : 3;
+      return distances + 2;
+    }
+    distances[0] = 2;
+    distances += 2;
+  }
+  if (curMatch3 >= matchMinPos && cur[(ptrdiff_t)curMatch3 - lzPos] == cur[0])
+  {
+    distances[1] = lzPos - curMatch3 - 1;
+    if (cur[(ptrdiff_t)curMatch3 - lzPos + 3] == cur[3])
+    {
+      distances[0] = 4;
+      return distances + 2;
+    }
+    distances[0] = 3;
+    distances += 2;
+  }
+
+  if (curMatch4 >= matchMinPos)
+    if (
+      cur[(ptrdiff_t)curMatch4 - lzPos] == cur[0] &&
+      cur[(ptrdiff_t)curMatch4 - lzPos + 3] == cur[3]
+      )
+    {
+      *distances++ = 4;
+      *distances++ = lzPos - curMatch4 - 1;
+    }
+  return distances;
+}
+*/
+
+#define INCREASE_LZ_POS p->lzPos++; p->pointerToCurPos++;
+
+UInt32 MatchFinderMt2_GetMatches(CMatchFinderMt *p, UInt32 *distances)
+{
+  const UInt32 *btBuf = p->btBuf + p->btBufPos;
+  UInt32 len = *btBuf++;
+  p->btBufPos += 1 + len;
+  p->btNumAvailBytes--;
+  {
+    UInt32 i;
+    for (i = 0; i < len; i += 2)
+    {
+      *distances++ = *btBuf++;
+      *distances++ = *btBuf++;
+    }
+  }
+  INCREASE_LZ_POS
+  return len;
+}
+
+UInt32 MatchFinderMt_GetMatches(CMatchFinderMt *p, UInt32 *distances)
+{
+  const UInt32 *btBuf = p->btBuf + p->btBufPos;
+  UInt32 len = *btBuf++;
+  p->btBufPos += 1 + len;
+
+  if (len == 0)
+  {
+    if (p->btNumAvailBytes-- >= 4)
+      len = (UInt32)(p->MixMatchesFunc(p, p->lzPos - p->historySize, distances) - (distances));
+  }
+  else
+  {
+    /* Condition: there are matches in btBuf with length < p->numHashBytes */
+    UInt32 *distances2;
+    p->btNumAvailBytes--;
+    distances2 = p->MixMatchesFunc(p, p->lzPos - btBuf[1], distances);
+    do
+    {
+      *distances2++ = *btBuf++;
+      *distances2++ = *btBuf++;
+    }
+    while ((len -= 2) != 0);
+    len  = (UInt32)(distances2 - (distances));
+  }
+  INCREASE_LZ_POS
+  return len;
+}
+
+#define SKIP_HEADER2_MT  do { GET_NEXT_BLOCK_IF_REQUIRED
+#define SKIP_HEADER_MT(n) SKIP_HEADER2_MT if (p->btNumAvailBytes-- >= (n)) { const Byte *cur = p->pointerToCurPos; UInt32 *hash = p->hash;
+#define SKIP_FOOTER_MT } INCREASE_LZ_POS p->btBufPos += p->btBuf[p->btBufPos] + 1; } while (--num != 0);
+
+void MatchFinderMt0_Skip(CMatchFinderMt *p, UInt32 num)
+{
+  SKIP_HEADER2_MT { p->btNumAvailBytes--;
+  SKIP_FOOTER_MT
+}
+
+void MatchFinderMt2_Skip(CMatchFinderMt *p, UInt32 num)
+{
+  SKIP_HEADER_MT(2)
+      UInt32 hash2Value;
+      MT_HASH2_CALC
+      hash[hash2Value] = p->lzPos;
+  SKIP_FOOTER_MT
+}
+
+void MatchFinderMt3_Skip(CMatchFinderMt *p, UInt32 num)
+{
+  SKIP_HEADER_MT(3)
+      UInt32 hash2Value, hash3Value;
+      MT_HASH3_CALC
+      hash[kFix3HashSize + hash3Value] =
+      hash[                hash2Value] =
+        p->lzPos;
+  SKIP_FOOTER_MT
+}
+
+/*
+void MatchFinderMt4_Skip(CMatchFinderMt *p, UInt32 num)
+{
+  SKIP_HEADER_MT(4)
+      UInt32 hash2Value, hash3Value, hash4Value;
+      MT_HASH4_CALC
+      hash[kFix4HashSize + hash4Value] =
+      hash[kFix3HashSize + hash3Value] =
+      hash[                hash2Value] =
+        p->lzPos;
+  SKIP_FOOTER_MT
+}
+*/
+
+void MatchFinderMt_CreateVTable(CMatchFinderMt *p, IMatchFinder *vTable)
+{
+  vTable->Init = (Mf_Init_Func)MatchFinderMt_Init;
+  vTable->GetIndexByte = (Mf_GetIndexByte_Func)MatchFinderMt_GetIndexByte;
+  vTable->GetNumAvailableBytes = (Mf_GetNumAvailableBytes_Func)MatchFinderMt_GetNumAvailableBytes;
+  vTable->GetPointerToCurrentPos = (Mf_GetPointerToCurrentPos_Func)MatchFinderMt_GetPointerToCurrentPos;
+  vTable->GetMatches = (Mf_GetMatches_Func)MatchFinderMt_GetMatches;
+  switch(p->MatchFinder->numHashBytes)
+  {
+    case 2:
+      p->GetHeadsFunc = GetHeads2;
+      p->MixMatchesFunc = (Mf_Mix_Matches)0;
+      vTable->Skip = (Mf_Skip_Func)MatchFinderMt0_Skip;
+      vTable->GetMatches = (Mf_GetMatches_Func)MatchFinderMt2_GetMatches;
+      break;
+    case 3:
+      p->GetHeadsFunc = GetHeads3;
+      p->MixMatchesFunc = (Mf_Mix_Matches)MixMatches2;
+      vTable->Skip = (Mf_Skip_Func)MatchFinderMt2_Skip;
+      break;
+    default:
+    /* case 4: */
+      p->GetHeadsFunc = p->MatchFinder->bigHash ? GetHeads4b : GetHeads4;
+      /* p->GetHeadsFunc = GetHeads4; */
+      p->MixMatchesFunc = (Mf_Mix_Matches)MixMatches3;
+      vTable->Skip = (Mf_Skip_Func)MatchFinderMt3_Skip;
+      break;
+    /*
+    default:
+      p->GetHeadsFunc = GetHeads5;
+      p->MixMatchesFunc = (Mf_Mix_Matches)MixMatches4;
+      vTable->Skip = (Mf_Skip_Func)MatchFinderMt4_Skip;
+      break;
+    */
+  }
+}