Mercurial > hg > graal-compiler
annotate src/share/vm/utilities/bitMap.hpp @ 1711:a6bff45449bc
6973570: OrderAccess::storestore() scales poorly on multi-socket x64 and sparc: cache-line ping-ponging
Summary: volatile store to static variable removed in favour of a volatile store to stack to avoid excessive cache coherency traffic; verified that the volatile store is not elided by any of our current compilers.
Reviewed-by: dholmes, dice, jcoomes, kvn
author | ysr |
---|---|
date | Tue, 10 Aug 2010 14:53:35 -0700 |
parents | c18cbe5936b8 |
children | f95d63e2154a |
rev | line source |
---|---|
0 | 1 /* |
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
844
diff
changeset
|
2 * Copyright (c) 1997, 2009, Oracle and/or its affiliates. All rights reserved. |
0 | 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 * | |
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
844
diff
changeset
|
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
844
diff
changeset
|
20 * or visit www.oracle.com if you need additional information or have any |
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
844
diff
changeset
|
21 * questions. |
0 | 22 * |
23 */ | |
24 | |
342 | 25 // Forward decl; |
26 class BitMapClosure; | |
0 | 27 |
342 | 28 // Operations for bitmaps represented as arrays of unsigned integers. |
29 // Bit offsets are numbered from 0 to size-1. | |
0 | 30 |
31 class BitMap VALUE_OBJ_CLASS_SPEC { | |
32 friend class BitMap2D; | |
33 | |
34 public: | |
35 typedef size_t idx_t; // Type used for bit and word indices. | |
342 | 36 typedef uintptr_t bm_word_t; // Element type of array that represents |
37 // the bitmap. | |
0 | 38 |
39 // Hints for range sizes. | |
40 typedef enum { | |
41 unknown_range, small_range, large_range | |
42 } RangeSizeHint; | |
43 | |
44 private: | |
342 | 45 bm_word_t* _map; // First word in bitmap |
46 idx_t _size; // Size of bitmap (in bits) | |
0 | 47 |
48 // Puts the given value at the given offset, using resize() to size | |
49 // the bitmap appropriately if needed using factor-of-two expansion. | |
50 void at_put_grow(idx_t index, bool value); | |
51 | |
52 protected: | |
53 // Return the position of bit within the word that contains it (e.g., if | |
54 // bitmap words are 32 bits, return a number 0 <= n <= 31). | |
55 static idx_t bit_in_word(idx_t bit) { return bit & (BitsPerWord - 1); } | |
56 | |
57 // Return a mask that will select the specified bit, when applied to the word | |
58 // containing the bit. | |
342 | 59 static bm_word_t bit_mask(idx_t bit) { return (bm_word_t)1 << bit_in_word(bit); } |
0 | 60 |
61 // Return the index of the word containing the specified bit. | |
62 static idx_t word_index(idx_t bit) { return bit >> LogBitsPerWord; } | |
63 | |
64 // Return the bit number of the first bit in the specified word. | |
65 static idx_t bit_index(idx_t word) { return word << LogBitsPerWord; } | |
66 | |
67 // Return the array of bitmap words, or a specific word from it. | |
342 | 68 bm_word_t* map() const { return _map; } |
69 bm_word_t map(idx_t word) const { return _map[word]; } | |
0 | 70 |
71 // Return a pointer to the word containing the specified bit. | |
342 | 72 bm_word_t* word_addr(idx_t bit) const { return map() + word_index(bit); } |
0 | 73 |
74 // Set a word to a specified value or to all ones; clear a word. | |
342 | 75 void set_word (idx_t word, bm_word_t val) { _map[word] = val; } |
0 | 76 void set_word (idx_t word) { set_word(word, ~(uintptr_t)0); } |
77 void clear_word(idx_t word) { _map[word] = 0; } | |
78 | |
79 // Utilities for ranges of bits. Ranges are half-open [beg, end). | |
80 | |
81 // Ranges within a single word. | |
342 | 82 bm_word_t inverted_bit_mask_for_range(idx_t beg, idx_t end) const; |
83 void set_range_within_word (idx_t beg, idx_t end); | |
84 void clear_range_within_word (idx_t beg, idx_t end); | |
85 void par_put_range_within_word (idx_t beg, idx_t end, bool value); | |
0 | 86 |
87 // Ranges spanning entire words. | |
342 | 88 void set_range_of_words (idx_t beg, idx_t end); |
89 void clear_range_of_words (idx_t beg, idx_t end); | |
90 void set_large_range_of_words (idx_t beg, idx_t end); | |
91 void clear_large_range_of_words (idx_t beg, idx_t end); | |
0 | 92 |
93 // The index of the first full word in a range. | |
342 | 94 idx_t word_index_round_up(idx_t bit) const; |
0 | 95 |
809
6e2afda171db
6849716: BitMap - performance regression introduced with G1
jcoomes
parents:
342
diff
changeset
|
96 // Verification. |
6e2afda171db
6849716: BitMap - performance regression introduced with G1
jcoomes
parents:
342
diff
changeset
|
97 inline void verify_index(idx_t index) const NOT_DEBUG_RETURN; |
6e2afda171db
6849716: BitMap - performance regression introduced with G1
jcoomes
parents:
342
diff
changeset
|
98 inline void verify_range(idx_t beg_index, idx_t end_index) const |
6e2afda171db
6849716: BitMap - performance regression introduced with G1
jcoomes
parents:
342
diff
changeset
|
99 NOT_DEBUG_RETURN; |
0 | 100 |
809
6e2afda171db
6849716: BitMap - performance regression introduced with G1
jcoomes
parents:
342
diff
changeset
|
101 // Statistics. |
342 | 102 static idx_t* _pop_count_table; |
103 static void init_pop_count_table(); | |
104 static idx_t num_set_bits(bm_word_t w); | |
105 static idx_t num_set_bits_from_table(unsigned char c); | |
0 | 106 |
107 public: | |
108 | |
109 // Constructs a bitmap with no map, and size 0. | |
110 BitMap() : _map(NULL), _size(0) {} | |
111 | |
342 | 112 // Constructs a bitmap with the given map and size. |
113 BitMap(bm_word_t* map, idx_t size_in_bits); | |
0 | 114 |
342 | 115 // Constructs an empty bitmap of the given size (that is, this clears the |
116 // new bitmap). Allocates the map array in resource area if | |
117 // "in_resource_area" is true, else in the C heap. | |
118 BitMap(idx_t size_in_bits, bool in_resource_area = true); | |
0 | 119 |
342 | 120 // Set the map and size. |
121 void set_map(bm_word_t* map) { _map = map; } | |
0 | 122 void set_size(idx_t size_in_bits) { _size = size_in_bits; } |
123 | |
342 | 124 // Allocates necessary data structure, either in the resource area |
125 // or in the C heap, as indicated by "in_resource_area." | |
0 | 126 // Preserves state currently in bit map by copying data. |
127 // Zeros any newly-addressable bits. | |
342 | 128 // If "in_resource_area" is false, frees the current map. |
129 // (Note that this assumes that all calls to "resize" on the same BitMap | |
130 // use the same value for "in_resource_area".) | |
131 void resize(idx_t size_in_bits, bool in_resource_area = true); | |
0 | 132 |
133 // Accessing | |
134 idx_t size() const { return _size; } | |
135 idx_t size_in_words() const { | |
136 return word_index(size() + BitsPerWord - 1); | |
137 } | |
138 | |
139 bool at(idx_t index) const { | |
140 verify_index(index); | |
141 return (*word_addr(index) & bit_mask(index)) != 0; | |
142 } | |
143 | |
144 // Align bit index up or down to the next bitmap word boundary, or check | |
145 // alignment. | |
146 static idx_t word_align_up(idx_t bit) { | |
147 return align_size_up(bit, BitsPerWord); | |
148 } | |
149 static idx_t word_align_down(idx_t bit) { | |
150 return align_size_down(bit, BitsPerWord); | |
151 } | |
152 static bool is_word_aligned(idx_t bit) { | |
153 return word_align_up(bit) == bit; | |
154 } | |
155 | |
156 // Set or clear the specified bit. | |
157 inline void set_bit(idx_t bit); | |
342 | 158 void clear_bit(idx_t bit); |
0 | 159 |
160 // Atomically set or clear the specified bit. | |
342 | 161 bool par_set_bit(idx_t bit); |
162 bool par_clear_bit(idx_t bit); | |
0 | 163 |
164 // Put the given value at the given offset. The parallel version | |
165 // will CAS the value into the bitmap and is quite a bit slower. | |
166 // The parallel version also returns a value indicating if the | |
167 // calling thread was the one that changed the value of the bit. | |
168 void at_put(idx_t index, bool value); | |
169 bool par_at_put(idx_t index, bool value); | |
170 | |
171 // Update a range of bits. Ranges are half-open [beg, end). | |
172 void set_range (idx_t beg, idx_t end); | |
173 void clear_range (idx_t beg, idx_t end); | |
174 void set_large_range (idx_t beg, idx_t end); | |
175 void clear_large_range (idx_t beg, idx_t end); | |
176 void at_put_range(idx_t beg, idx_t end, bool value); | |
177 void par_at_put_range(idx_t beg, idx_t end, bool value); | |
178 void at_put_large_range(idx_t beg, idx_t end, bool value); | |
179 void par_at_put_large_range(idx_t beg, idx_t end, bool value); | |
180 | |
181 // Update a range of bits, using a hint about the size. Currently only | |
182 // inlines the predominant case of a 1-bit range. Works best when hint is a | |
183 // compile-time constant. | |
342 | 184 void set_range(idx_t beg, idx_t end, RangeSizeHint hint); |
185 void clear_range(idx_t beg, idx_t end, RangeSizeHint hint); | |
186 void par_set_range(idx_t beg, idx_t end, RangeSizeHint hint); | |
187 void par_clear_range (idx_t beg, idx_t end, RangeSizeHint hint); | |
188 | |
189 // It performs the union operation between subsets of equal length | |
190 // of two bitmaps (the target bitmap of the method and the | |
191 // from_bitmap) and stores the result to the target bitmap. The | |
192 // from_start_index represents the first bit index of the subrange | |
193 // of the from_bitmap. The to_start_index is the equivalent of the | |
194 // target bitmap. Both indexes should be word-aligned, i.e. they | |
195 // should correspond to the first bit on a bitmap word (it's up to | |
196 // the caller to ensure this; the method does check it). The length | |
197 // of the subset is specified with word_num and it is in number of | |
198 // bitmap words. The caller should ensure that this is at least 2 | |
199 // (smaller ranges are not support to save extra checks). Again, | |
200 // this is checked in the method. | |
201 // | |
202 // Atomicity concerns: it is assumed that any contention on the | |
203 // target bitmap with other threads will happen on the first and | |
204 // last words; the ones in between will be "owned" exclusively by | |
205 // the calling thread and, in fact, they will already be 0. So, the | |
206 // method performs a CAS on the first word, copies the next | |
207 // word_num-2 words, and finally performs a CAS on the last word. | |
208 void mostly_disjoint_range_union(BitMap* from_bitmap, | |
209 idx_t from_start_index, | |
210 idx_t to_start_index, | |
211 size_t word_num); | |
212 | |
0 | 213 |
214 // Clearing | |
215 void clear_large(); | |
342 | 216 inline void clear(); |
0 | 217 |
342 | 218 // Iteration support. Returns "true" if the iteration completed, false |
219 // if the iteration terminated early (because the closure "blk" returned | |
220 // false). | |
221 bool iterate(BitMapClosure* blk, idx_t leftIndex, idx_t rightIndex); | |
222 bool iterate(BitMapClosure* blk) { | |
0 | 223 // call the version that takes an interval |
342 | 224 return iterate(blk, 0, size()); |
0 | 225 } |
226 | |
342 | 227 // Looking for 1's and 0's at indices equal to or greater than "l_index", |
228 // stopping if none has been found before "r_index", and returning | |
229 // "r_index" (which must be at most "size") in that case. | |
230 idx_t get_next_one_offset_inline (idx_t l_index, idx_t r_index) const; | |
231 idx_t get_next_zero_offset_inline(idx_t l_index, idx_t r_index) const; | |
232 | |
233 // Like "get_next_one_offset_inline", except requires that "r_index" is | |
234 // aligned to bitsizeof(bm_word_t). | |
235 idx_t get_next_one_offset_inline_aligned_right(idx_t l_index, | |
236 idx_t r_index) const; | |
237 | |
238 // Non-inline versionsof the above. | |
0 | 239 idx_t get_next_one_offset (idx_t l_index, idx_t r_index) const; |
240 idx_t get_next_zero_offset(idx_t l_index, idx_t r_index) const; | |
241 | |
242 idx_t get_next_one_offset(idx_t offset) const { | |
243 return get_next_one_offset(offset, size()); | |
244 } | |
245 idx_t get_next_zero_offset(idx_t offset) const { | |
246 return get_next_zero_offset(offset, size()); | |
247 } | |
248 | |
342 | 249 // Returns the number of bits set in the bitmap. |
250 idx_t count_one_bits() const; | |
0 | 251 |
252 // Set operations. | |
253 void set_union(BitMap bits); | |
254 void set_difference(BitMap bits); | |
255 void set_intersection(BitMap bits); | |
256 // Returns true iff "this" is a superset of "bits". | |
257 bool contains(const BitMap bits) const; | |
258 // Returns true iff "this and "bits" have a non-empty intersection. | |
259 bool intersects(const BitMap bits) const; | |
260 | |
261 // Returns result of whether this map changed | |
262 // during the operation | |
263 bool set_union_with_result(BitMap bits); | |
264 bool set_difference_with_result(BitMap bits); | |
265 bool set_intersection_with_result(BitMap bits); | |
266 | |
342 | 267 // Requires the submap of "bits" starting at offset to be at least as |
268 // large as "this". Modifies "this" to be the intersection of its | |
269 // current contents and the submap of "bits" starting at "offset" of the | |
270 // same length as "this." | |
271 // (For expedience, currently requires the offset to be aligned to the | |
272 // bitsize of a uintptr_t. This should go away in the future though it | |
273 // will probably remain a good case to optimize.) | |
274 void set_intersection_at_offset(BitMap bits, idx_t offset); | |
275 | |
0 | 276 void set_from(BitMap bits); |
277 | |
278 bool is_same(BitMap bits); | |
279 | |
280 // Test if all bits are set or cleared | |
281 bool is_full() const; | |
282 bool is_empty() const; | |
283 | |
284 | |
285 #ifndef PRODUCT | |
286 public: | |
287 // Printing | |
288 void print_on(outputStream* st) const; | |
289 #endif | |
290 }; | |
291 | |
292 // Convenience class wrapping BitMap which provides multiple bits per slot. | |
293 class BitMap2D VALUE_OBJ_CLASS_SPEC { | |
294 public: | |
342 | 295 typedef BitMap::idx_t idx_t; // Type used for bit and word indices. |
296 typedef BitMap::bm_word_t bm_word_t; // Element type of array that | |
297 // represents the bitmap. | |
0 | 298 private: |
299 BitMap _map; | |
300 idx_t _bits_per_slot; | |
301 | |
302 idx_t bit_index(idx_t slot_index, idx_t bit_within_slot_index) const { | |
303 return slot_index * _bits_per_slot + bit_within_slot_index; | |
304 } | |
305 | |
306 void verify_bit_within_slot_index(idx_t index) const { | |
307 assert(index < _bits_per_slot, "bit_within_slot index out of bounds"); | |
308 } | |
309 | |
310 public: | |
311 // Construction. bits_per_slot must be greater than 0. | |
342 | 312 BitMap2D(bm_word_t* map, idx_t size_in_slots, idx_t bits_per_slot); |
0 | 313 |
314 // Allocates necessary data structure in resource area. bits_per_slot must be greater than 0. | |
315 BitMap2D(idx_t size_in_slots, idx_t bits_per_slot); | |
316 | |
317 idx_t size_in_bits() { | |
318 return _map.size(); | |
319 } | |
320 | |
321 // Returns number of full slots that have been allocated | |
322 idx_t size_in_slots() { | |
323 // Round down | |
324 return _map.size() / _bits_per_slot; | |
325 } | |
326 | |
327 bool is_valid_index(idx_t slot_index, idx_t bit_within_slot_index) { | |
328 verify_bit_within_slot_index(bit_within_slot_index); | |
329 return (bit_index(slot_index, bit_within_slot_index) < size_in_bits()); | |
330 } | |
331 | |
332 bool at(idx_t slot_index, idx_t bit_within_slot_index) const { | |
333 verify_bit_within_slot_index(bit_within_slot_index); | |
334 return _map.at(bit_index(slot_index, bit_within_slot_index)); | |
335 } | |
336 | |
337 void set_bit(idx_t slot_index, idx_t bit_within_slot_index) { | |
338 verify_bit_within_slot_index(bit_within_slot_index); | |
339 _map.set_bit(bit_index(slot_index, bit_within_slot_index)); | |
340 } | |
341 | |
342 void clear_bit(idx_t slot_index, idx_t bit_within_slot_index) { | |
343 verify_bit_within_slot_index(bit_within_slot_index); | |
344 _map.clear_bit(bit_index(slot_index, bit_within_slot_index)); | |
345 } | |
346 | |
347 void at_put(idx_t slot_index, idx_t bit_within_slot_index, bool value) { | |
348 verify_bit_within_slot_index(bit_within_slot_index); | |
349 _map.at_put(bit_index(slot_index, bit_within_slot_index), value); | |
350 } | |
351 | |
352 void at_put_grow(idx_t slot_index, idx_t bit_within_slot_index, bool value) { | |
353 verify_bit_within_slot_index(bit_within_slot_index); | |
354 _map.at_put_grow(bit_index(slot_index, bit_within_slot_index), value); | |
355 } | |
356 | |
342 | 357 void clear(); |
0 | 358 }; |
359 | |
342 | 360 // Closure for iterating over BitMaps |
0 | 361 |
342 | 362 class BitMapClosure VALUE_OBJ_CLASS_SPEC { |
363 public: | |
364 // Callback when bit in map is set. Should normally return "true"; | |
365 // return of false indicates that the bitmap iteration should terminate. | |
366 virtual bool do_bit(BitMap::idx_t offset) = 0; | |
367 }; |