bitMap.inline.hpp revision 1472:c18cbe5936b8 
1/*
2 * Copyright (c) 2005, 2009, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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23 */
24
25#ifdef ASSERT
26inline void BitMap::verify_index(idx_t index) const {
27  assert(index < _size, "BitMap index out of bounds");
28}
29
30inline void BitMap::verify_range(idx_t beg_index, idx_t end_index) const {
31  assert(beg_index <= end_index, "BitMap range error");
32  // Note that [0,0) and [size,size) are both valid ranges.
33  if (end_index != _size) verify_index(end_index);
34}
35#endif // #ifdef ASSERT
36
37inline void BitMap::set_bit(idx_t bit) {
38  verify_index(bit);
39  *word_addr(bit) |= bit_mask(bit);
40}
41
42inline void BitMap::clear_bit(idx_t bit) {
43  verify_index(bit);
44  *word_addr(bit) &= ~bit_mask(bit);
45}
46
47inline bool BitMap::par_set_bit(idx_t bit) {
48  verify_index(bit);
49  volatile idx_t* const addr = word_addr(bit);
50  const idx_t mask = bit_mask(bit);
51  idx_t old_val = *addr;
52
53  do {
54    const idx_t new_val = old_val | mask;
55    if (new_val == old_val) {
56      return false;     // Someone else beat us to it.
57    }
58    const idx_t cur_val = (idx_t) Atomic::cmpxchg_ptr((void*) new_val,
59                                                      (volatile void*) addr,
60                                                      (void*) old_val);
61    if (cur_val == old_val) {
62      return true;      // Success.
63    }
64    old_val = cur_val;  // The value changed, try again.
65  } while (true);
66}
67
68inline bool BitMap::par_clear_bit(idx_t bit) {
69  verify_index(bit);
70  volatile idx_t* const addr = word_addr(bit);
71  const idx_t mask = ~bit_mask(bit);
72  idx_t old_val = *addr;
73
74  do {
75    const idx_t new_val = old_val & mask;
76    if (new_val == old_val) {
77      return false;     // Someone else beat us to it.
78    }
79    const idx_t cur_val = (idx_t) Atomic::cmpxchg_ptr((void*) new_val,
80                                                      (volatile void*) addr,
81                                                      (void*) old_val);
82    if (cur_val == old_val) {
83      return true;      // Success.
84    }
85    old_val = cur_val;  // The value changed, try again.
86  } while (true);
87}
88
89inline void BitMap::set_range(idx_t beg, idx_t end, RangeSizeHint hint) {
90  if (hint == small_range && end - beg == 1) {
91    set_bit(beg);
92  } else {
93    if (hint == large_range) {
94      set_large_range(beg, end);
95    } else {
96      set_range(beg, end);
97    }
98  }
99}
100
101inline void BitMap::clear_range(idx_t beg, idx_t end, RangeSizeHint hint) {
102  if (hint == small_range && end - beg == 1) {
103    clear_bit(beg);
104  } else {
105    if (hint == large_range) {
106      clear_large_range(beg, end);
107    } else {
108      clear_range(beg, end);
109    }
110  }
111}
112
113inline void BitMap::par_set_range(idx_t beg, idx_t end, RangeSizeHint hint) {
114  if (hint == small_range && end - beg == 1) {
115    par_at_put(beg, true);
116  } else {
117    if (hint == large_range) {
118      par_at_put_large_range(beg, end, true);
119    } else {
120      par_at_put_range(beg, end, true);
121    }
122  }
123}
124
125inline void BitMap::set_range_of_words(idx_t beg, idx_t end) {
126  bm_word_t* map = _map;
127  for (idx_t i = beg; i < end; ++i) map[i] = ~(uintptr_t)0;
128}
129
130
131inline void BitMap::clear_range_of_words(idx_t beg, idx_t end) {
132  bm_word_t* map = _map;
133  for (idx_t i = beg; i < end; ++i) map[i] = 0;
134}
135
136
137inline void BitMap::clear() {
138  clear_range_of_words(0, size_in_words());
139}
140
141
142inline void BitMap::par_clear_range(idx_t beg, idx_t end, RangeSizeHint hint) {
143  if (hint == small_range && end - beg == 1) {
144    par_at_put(beg, false);
145  } else {
146    if (hint == large_range) {
147      par_at_put_large_range(beg, end, false);
148    } else {
149      par_at_put_range(beg, end, false);
150    }
151  }
152}
153
154inline BitMap::idx_t
155BitMap::get_next_one_offset_inline(idx_t l_offset, idx_t r_offset) const {
156  assert(l_offset <= size(), "BitMap index out of bounds");
157  assert(r_offset <= size(), "BitMap index out of bounds");
158  assert(l_offset <= r_offset, "l_offset > r_offset ?");
159
160  if (l_offset == r_offset) {
161    return l_offset;
162  }
163  idx_t   index = word_index(l_offset);
164  idx_t r_index = word_index(r_offset-1) + 1;
165  idx_t res_offset = l_offset;
166
167  // check bits including and to the _left_ of offset's position
168  idx_t pos = bit_in_word(res_offset);
169  idx_t res = map(index) >> pos;
170  if (res != (uintptr_t)NoBits) {
171    // find the position of the 1-bit
172    for (; !(res & 1); res_offset++) {
173      res = res >> 1;
174    }
175    assert(res_offset >= l_offset &&
176           res_offset < r_offset, "just checking");
177    return MIN2(res_offset, r_offset);
178  }
179  // skip over all word length 0-bit runs
180  for (index++; index < r_index; index++) {
181    res = map(index);
182    if (res != (uintptr_t)NoBits) {
183      // found a 1, return the offset
184      for (res_offset = bit_index(index); !(res & 1); res_offset++) {
185        res = res >> 1;
186      }
187      assert(res & 1, "tautology; see loop condition");
188      assert(res_offset >= l_offset, "just checking");
189      return MIN2(res_offset, r_offset);
190    }
191  }
192  return r_offset;
193}
194
195inline BitMap::idx_t
196BitMap::get_next_zero_offset_inline(idx_t l_offset, idx_t r_offset) const {
197  assert(l_offset <= size(), "BitMap index out of bounds");
198  assert(r_offset <= size(), "BitMap index out of bounds");
199  assert(l_offset <= r_offset, "l_offset > r_offset ?");
200
201  if (l_offset == r_offset) {
202    return l_offset;
203  }
204  idx_t   index = word_index(l_offset);
205  idx_t r_index = word_index(r_offset-1) + 1;
206  idx_t res_offset = l_offset;
207
208  // check bits including and to the _left_ of offset's position
209  idx_t pos = res_offset & (BitsPerWord - 1);
210  idx_t res = (map(index) >> pos) | left_n_bits((int)pos);
211
212  if (res != (uintptr_t)AllBits) {
213    // find the position of the 0-bit
214    for (; res & 1; res_offset++) {
215      res = res >> 1;
216    }
217    assert(res_offset >= l_offset, "just checking");
218    return MIN2(res_offset, r_offset);
219  }
220  // skip over all word length 1-bit runs
221  for (index++; index < r_index; index++) {
222    res = map(index);
223    if (res != (uintptr_t)AllBits) {
224      // found a 0, return the offset
225      for (res_offset = index << LogBitsPerWord; res & 1;
226           res_offset++) {
227        res = res >> 1;
228      }
229      assert(!(res & 1), "tautology; see loop condition");
230      assert(res_offset >= l_offset, "just checking");
231      return MIN2(res_offset, r_offset);
232    }
233  }
234  return r_offset;
235}
236
237inline BitMap::idx_t
238BitMap::get_next_one_offset_inline_aligned_right(idx_t l_offset,
239                                                 idx_t r_offset) const
240{
241  verify_range(l_offset, r_offset);
242  assert(bit_in_word(r_offset) == 0, "r_offset not word-aligned");
243
244  if (l_offset == r_offset) {
245    return l_offset;
246  }
247  idx_t   index = word_index(l_offset);
248  idx_t r_index = word_index(r_offset);
249  idx_t res_offset = l_offset;
250
251  // check bits including and to the _left_ of offset's position
252  idx_t res = map(index) >> bit_in_word(res_offset);
253  if (res != (uintptr_t)NoBits) {
254    // find the position of the 1-bit
255    for (; !(res & 1); res_offset++) {
256      res = res >> 1;
257    }
258    assert(res_offset >= l_offset &&
259           res_offset < r_offset, "just checking");
260    return res_offset;
261  }
262  // skip over all word length 0-bit runs
263  for (index++; index < r_index; index++) {
264    res = map(index);
265    if (res != (uintptr_t)NoBits) {
266      // found a 1, return the offset
267      for (res_offset = bit_index(index); !(res & 1); res_offset++) {
268        res = res >> 1;
269      }
270      assert(res & 1, "tautology; see loop condition");
271      assert(res_offset >= l_offset && res_offset < r_offset, "just checking");
272      return res_offset;
273    }
274  }
275  return r_offset;
276}
277
278
279// Returns a bit mask for a range of bits [beg, end) within a single word.  Each
280// bit in the mask is 0 if the bit is in the range, 1 if not in the range.  The
281// returned mask can be used directly to clear the range, or inverted to set the
282// range.  Note:  end must not be 0.
283inline BitMap::bm_word_t
284BitMap::inverted_bit_mask_for_range(idx_t beg, idx_t end) const {
285  assert(end != 0, "does not work when end == 0");
286  assert(beg == end || word_index(beg) == word_index(end - 1),
287         "must be a single-word range");
288  bm_word_t mask = bit_mask(beg) - 1;   // low (right) bits
289  if (bit_in_word(end) != 0) {
290    mask |= ~(bit_mask(end) - 1);       // high (left) bits
291  }
292  return mask;
293}
294
295inline void BitMap::set_large_range_of_words(idx_t beg, idx_t end) {
296  memset(_map + beg, ~(unsigned char)0, (end - beg) * sizeof(uintptr_t));
297}
298
299inline void BitMap::clear_large_range_of_words(idx_t beg, idx_t end) {
300  memset(_map + beg, 0, (end - beg) * sizeof(uintptr_t));
301}
302
303inline BitMap::idx_t BitMap::word_index_round_up(idx_t bit) const {
304  idx_t bit_rounded_up = bit + (BitsPerWord - 1);
305  // Check for integer arithmetic overflow.
306  return bit_rounded_up > bit ? word_index(bit_rounded_up) : size_in_words();
307}
308
309inline BitMap::idx_t BitMap::get_next_one_offset(idx_t l_offset,
310                                          idx_t r_offset) const {
311  return get_next_one_offset_inline(l_offset, r_offset);
312}
313
314inline BitMap::idx_t BitMap::get_next_zero_offset(idx_t l_offset,
315                                           idx_t r_offset) const {
316  return get_next_zero_offset_inline(l_offset, r_offset);
317}
318
319inline void BitMap2D::clear() {
320  _map.clear();
321}
322