summaryrefslogtreecommitdiffstats
path: root/util/qlalr/compress.cpp
blob: 6e9d055839ddfc9717d103934dfdc5cec7ff6e84 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the test suite module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/


#include <QtCore/QtDebug>
#include <QtCore/QList>

#include <algorithm>
#include <iterator>
#include <iostream>
#include "compress.h"

#define QLALR_NO_CHECK_SORTED_TABLE

struct _Fit: public std::binary_function<int, int, bool>
{
  inline bool operator () (int a, int b) const
  {
    return a == 0 || b == 0 || a == b;
  }
};

struct _PerfectMatch: public std::binary_function<int, int, bool>
{
  inline bool operator () (int a, int b) const
  { return a == b; }
};

struct _GenerateCheck
{
  QVector<int>::const_iterator iterator;
  int initial;

  _GenerateCheck (QVector<int>::const_iterator it, int i):
    iterator (it),
    initial (i) {}

  inline int operator () ()
  {
    int check = initial++;
    return *iterator++ ? check : -1;
  }
};

class UncompressedRow
{
public:
  typedef const int *const_iterator;
  typedef const int *iterator;

public:
  inline UncompressedRow ():
    _M_index (0),
    _M_begin (0),
    _M_end (0),
    _M_beginNonZeros (0),
    _M_endNonZeros (0) {}

  inline UncompressedRow (int index, const_iterator begin, const_iterator end)
  { assign (index, begin, end); }

  inline int index () const { return _M_index; }
  inline const_iterator begin () const { return _M_begin; }
  inline const_iterator end () const { return _M_end; }

  inline void assign (int index, const_iterator begin, const_iterator end)
  {
    _M_index = index;
    _M_begin = begin;
    _M_end = end;

    _M_beginNonZeros = _M_begin;
    _M_endNonZeros = _M_end;

    for (_M_beginNonZeros = _M_begin; _M_beginNonZeros != _M_end && ! _M_beginNonZeros [0]; ++_M_beginNonZeros)
      /*continue*/ ;

#if 0
    for (_M_endNonZeros = _M_end; _M_endNonZeros != _M_beginNonZeros && ! _M_endNonZeros [-1]; --_M_endNonZeros)
      /*continue*/ ;
#endif
  }

  inline int at (int index) const
  { return _M_begin [index]; }

  inline bool isEmpty () const
  { return _M_begin == _M_end; }

  inline int size () const
  { return _M_end - _M_begin; }

  inline int nonZeroElements () const
  { return _M_endNonZeros - _M_beginNonZeros; }

  inline int count (int value) const
  { return std::count (begin (), end (), value); }

  inline const_iterator beginNonZeros () const
  { return _M_beginNonZeros; }

  inline const_iterator endNonZeros () const
  { return _M_endNonZeros; }

private:
  int _M_index;
  const_iterator _M_begin;
  const_iterator _M_end;
  const_iterator _M_beginNonZeros;
  const_iterator _M_endNonZeros;
};

struct _SortUncompressedRow: public std::binary_function<UncompressedRow, UncompressedRow, bool>
{
  inline bool operator () (const UncompressedRow &a, const UncompressedRow &b) const
  { return a.count (0) > b.count (0); }
};

Compress::Compress ()
{
}

void Compress::operator () (int *table, int row_count, int column_count)
{
  index.clear ();
  info.clear ();
  check.clear ();

  QVector<UncompressedRow> sortedTable (row_count);

  for (int i = 0; i < row_count; ++i)
    {
      int *begin = &table [i * column_count];
      int *end = begin + column_count;

      sortedTable [i].assign (i, begin, end);
    }

  qSort (sortedTable.begin (), sortedTable.end (), _SortUncompressedRow ());

#ifndef QLALR_NO_CHECK_SORTED_TABLE
  int previous_zeros = INT_MAX;

  foreach (UncompressedRow row, sortedTable)
    {
      int zeros = row.count (0);

      Q_ASSERT (zeros <= previous_zeros);
      zeros = previous_zeros;
      qDebug () << "OK!";
    }
#endif

  index.fill (-999999, row_count);

  foreach (UncompressedRow row, sortedTable)
    {
      int first_token = std::distance (row.begin (), row.beginNonZeros ());
      QVector<int>::iterator pos = info.begin ();

      while (pos != info.end ())
        {
          if (pos == info.begin ())
            {
              // try to find a perfect match
              QVector<int>::iterator pm = std::search (pos, info.end (), row.beginNonZeros (), row.endNonZeros (), _PerfectMatch ());

              if (pm != info.end ())
                {
                  pos = pm;
                  break;
                }
            }

          pos = std::search (pos, info.end (), row.beginNonZeros (), row.endNonZeros (), _Fit ());

          if (pos == info.end ())
            break;

          int idx = std::distance (info.begin (), pos) - first_token;
          bool conflict = false;

          for (int j = 0; ! conflict && j < row.size (); ++j)
            {
              if (row.at (j) == 0)
                conflict |= idx + j >= 0 && check [idx + j] == j;

              else
                conflict |= check [idx + j] == j;
            }

          if (! conflict)
            break;

          ++pos;
        }

      if (pos == info.end ())
        {
          int size = info.size ();

          info.resize (info.size () + row.nonZeroElements ());
          check.resize (info.size ());

          std::fill (check.begin () + size, check.end (), -1);
          pos = info.begin () + size;
        }

      int offset = std::distance (info.begin (), pos);
      index [row.index ()] = offset - first_token;

      for (const int *it = row.beginNonZeros (); it != row.endNonZeros (); ++it, ++pos)
        {
          if (*it)
            *pos = *it;
        }

      int i = row.index ();

      for (int j = 0; j < row.size (); ++j)
        {
          if (row.at (j) == 0)
            continue;

          check [index [i] + j] = j;
        }
    }

#if 0
  foreach (UncompressedRow row, sortedTable)
    {
      int i = row.index ();
      Q_ASSERT (i < sortedTable.size ());

      for (int j = 0; j < row.size (); ++j)
        {
          if (row.at (j) == 0)
            {
              Q_ASSERT (index [i] + j < 0 || check [index [i] + j] != j);
              continue;
            }

          Q_ASSERT ( info [index [i] + j] == row.at (j));
          Q_ASSERT (check [index [i] + j] == j);
        }
    }
#endif
}