RtlpCoalesceFreeBlocks

_HEAP_FREE_ENTRY *__fastcall RtlpCoalesceFreeBlocks(
        _HEAP *Heap,
        _HEAP_FREE_ENTRY *FreeBlock,
        UINT64 *FreeSize,
        UINT64 *RemoveFromFreeList,
        UINT64 *a5,
        VOID *a6){
  _HEAP_FREE_ENTRY *v7; 
  unsigned __int64 v8; 
  char *v10; 
  unsigned int EncodeFlagMask; 
  INT64 *v12; 
  UINT64 v13; 
  INT64 v14; 
  INT64 v15; 
  INT64 v16; 
  unsigned int *BlocksIndex; 
  unsigned __int64 i; 
  unsigned int *v19; 
  int v20; 
  char v21; 
  SIZE_T v22; 
  SIZE_T v23; 
  __int64 v24; 
  UINT64 v25; 
  unsigned int v26; 
  INT64 *v27; 
  INT64 v28; 
  INT64 v29; 
  INT64 v30; 
  unsigned int *v31; 
  unsigned __int64 j; 
  unsigned int *v33; 
  INT64 v34; 
  char v35; 
  SIZE_T v36; 
  SIZE_T v37; 
  UINT64 v39; 
  v7 = FreeBlock;
  v8 = 16
     * (Heap->Encoding.UnpackedEntry.PreviousSize ^ (unsigned __int64)FreeBlock->HeapEntry.UnpackedEntry.PreviousSize);
  v10 = (char *)FreeBlock - v8;
  if( (_HEAP_FREE_ENTRY *)((char *)FreeBlock - v8) != FreeBlock )
  {
    EncodeFlagMask = Heap->EncodeFlagMask;
    if( (((unsigned __int8)v10[10] ^ Heap->Encoding.UnpackedEntry.Flags & (EncodeFlagMask >> 20)) & 1) == 0 )
    {
      if( EncodeFlagMask )
      {
        *((_DWORD *)v10 + 2) ^= Heap->Encoding.UnpackedEntry.SubSegmentCode;
        if( v10[11] != ((unsigned __int8)v10[8] ^ (unsigned __int8)(v10[9] ^ v10[10])) )
          RtlpAnalyzeHeapFailure((INT64)Heap, (UINT64)FreeBlock - v8);
      }
      v12 = (INT64 *)*((_QWORD *)v10 + 3);
      v13 = (UINT64)(v10 + 16);
      v14 = *((_QWORD *)v10 + 2);
      v15 = *v12;
      v16 = *(_QWORD *)(v14 + 8);
      if( *v12 == v16 && v15 == v13 )
      {
        Heap->TotalFreeSize -= *((unsigned __int16 *)v10 + 4);
        BlocksIndex = (unsigned int *)Heap->BlocksIndex;
        if( BlocksIndex )
        {
          for( i = BlocksIndex[2]; ; i = v19[2] )
          {
            if( *((unsigned __int16 *)v10 + 4) < i )
            {
              v20 = *((unsigned __int16 *)v10 + 4);
              goto LABEL_14;
            }
            v19 = *(unsigned int **)BlocksIndex;
            if( !*(_QWORD *)BlocksIndex )
              break;
            BlocksIndex = *(unsigned int **)BlocksIndex;
          }
          v20 = BlocksIndex[2] - 1;
LABEL_14:
          LODWORD(v39) = v20;
          LOBYTE(v13) = 1;
          RtlpHeapRemoveListEntry(
            (INT64)Heap,
            (INT64)BlocksIndex,
            v13,
            (INT64 *)v10 + 2,
            v39,
            *((unsigned __int16 *)v10 + 4));
        }
        *v12 = v14;
        *(_QWORD *)(v14 + 8) = v12;
        v21 = v10[10];
        if( (v21 & 4) != 0 )
        {
          v22 = 16i64 * *((unsigned __int16 *)v10 + 4) - 32;
          if( (v21 & 2) != 0 && v22 > 4 )
            v22 = 16i64 * *((unsigned __int16 *)v10 + 4) - 36;
          v23 = RtlCompareMemoryUlong(v10 + 32, v22, 0xFEEEFEEE);
          if( v23 != v22 )
          {
            DbgPrint("HEAP: Free Heap block %p modified at %p after it was freed\n", v10, &v10[v23 + 32]);
            if( (_BYTE)KdDebuggerEnabled )
              __debugbreak();
          }
        }
        v24 = *((unsigned __int16 *)v10 + 4);
        v7 = (_HEAP_FREE_ENTRY *)v10;
        v10[10] = 0;
        v10[15] = 0;
        *FreeSize += v24;
        *((_WORD *)v10 + 4) = *(_WORD *)FreeSize;
        *(_WORD *)&v10[16 * *FreeSize + 12] = Heap->Encoding.UnpackedEntry.PreviousSize ^ *(_WORD *)FreeSize;
      }
      else
      {
        RtlpLogHeapFailure(13i64, (INT64)Heap, v13, v16, v15, 0i64);
      }
    }
  }
  v25 = (UINT64)v7 + 16 * *FreeSize;
  if( Heap->EncodeFlagMask )
  {
    v26 = *(_DWORD *)(v25 + 8) ^ Heap->Encoding.UnpackedEntry.SubSegmentCode;
    if( HIBYTE(v26) != ((unsigned __int8)v26 ^ (unsigned __int8)(BYTE1(v26) ^ BYTE2(v26))) )
      RtlpLogHeapFailure(3i64, (INT64)Heap, v25, 0i64, 0i64, 0i64);
  }
  while( ((*(_BYTE *)(v25 + 10) ^ Heap->Encoding.UnpackedEntry.Flags & (Heap->EncodeFlagMask >> 20)) & 1) == 0 )
  {
    if( Heap->EncodeFlagMask )
    {
      *(_DWORD *)(v25 + 8) ^= Heap->Encoding.UnpackedEntry.SubSegmentCode;
      if( *(_BYTE *)(v25 + 11) != (*(_BYTE *)(v25 + 8) ^ (unsigned __int8)(*(_BYTE *)(v25 + 9) ^ *(_BYTE *)(v25 + 10))) )
        RtlpAnalyzeHeapFailure((INT64)Heap, v25);
    }
    v27 = *(INT64 **)(v25 + 24);
    v28 = *(_QWORD *)(v25 + 16);
    v29 = *v27;
    v30 = *(_QWORD *)(v28 + 8);
    if( *v27 == v30 && v29 == v25 + 16 )
    {
      Heap->TotalFreeSize -= *(unsigned __int16 *)(v25 + 8);
      v31 = (unsigned int *)Heap->BlocksIndex;
      if( v31 )
      {
        for( j = v31[2]; ; j = v33[2] )
        {
          if( *(unsigned __int16 *)(v25 + 8) < j )
          {
            v34 = *(unsigned __int16 *)(v25 + 8);
            goto LABEL_41;
          }
          v33 = *(unsigned int **)v31;
          if( !*(_QWORD *)v31 )
            break;
          v31 = *(unsigned int **)v31;
        }
        v34 = v31[2] - 1;
LABEL_41:
        LODWORD(v39) = v34;
        LOBYTE(v34) = 1;
        RtlpHeapRemoveListEntry((INT64)Heap, (INT64)v31, v34, (INT64 *)(v25 + 16), v39, *(unsigned __int16 *)(v25 + 8));
      }
      *v27 = v28;
      *(_QWORD *)(v28 + 8) = v27;
      v35 = *(_BYTE *)(v25 + 10);
      if( (v35 & 4) != 0 )
      {
        v36 = 16i64 * *(unsigned __int16 *)(v25 + 8) - 32;
        if( (v35 & 2) != 0 && v36 > 4 )
          v36 = 16i64 * *(unsigned __int16 *)(v25 + 8) - 36;
        v37 = RtlCompareMemoryUlong((PVOID)(v25 + 32), v36, 0xFEEEFEEE);
        if( v37 != v36 )
        {
          DbgPrint(
            "HEAP: Free Heap block %p modified at %p after it was freed\n",
            (const void *)v25,
            (const void *)(v37 + v25 + 32));
          if( (_BYTE)KdDebuggerEnabled )
            __debugbreak();
        }
      }
      v7->HeapEntry.UnpackedEntry.Flags = 0;
      v7->HeapEntry.UnpackedEntry.UnusedBytes = 0;
      *FreeSize += *(unsigned __int16 *)(v25 + 8);
      v7->HeapEntry.UnpackedEntry.Size = *(_WORD *)FreeSize;
      *(&v7->HeapEntry.UnpackedEntry.PreviousSize + 8 * *FreeSize) = Heap->Encoding.UnpackedEntry.PreviousSize ^ *(_WORD *)FreeSize;
      return v7;
    }
    RtlpLogHeapFailure(13i64, (INT64)Heap, v25 + 16, v30, v29, 0i64);
  }
  return v7;
}

Referenced by: