1 /*
2 * Copyright (c) 1998, 2011, 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
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_OPTO_INDEXSET_HPP
26 #define SHARE_VM_OPTO_INDEXSET_HPP
27
28 #include "memory/allocation.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "opto/compile.hpp"
31 #include "opto/regmask.hpp"
32
33 // This file defines the IndexSet class, a set of sparse integer indices.
34 // This data structure is used by the compiler in its liveness analysis and
35 // during register allocation.
36
37 //-------------------------------- class IndexSet ----------------------------
38 // An IndexSet is an adapter for high-performance BitMap implementation in
39 // VM utility classes. See JDK-8059461 for performance investigation.
40
41 class IndexSet : public ResourceObj {
42 friend class IndexSetIterator;
43
44 //-------------------------- Members ------------------------------------------
45 private:
46
47 // Underlying BitMap where we store the values
48 BitMap _map;
49
50 // The next IndexSet on the free list
51 IndexSet *_next;
52
53 //-------------------------- Free list operations ------------------------------
54 // Individual IndexSets can be placed on a free list. This is done in PhaseLive.
55 public:
56
57 IndexSet *next() {
58 return _next;
59 }
60
61 void set_next(IndexSet *next) {
62 _next = next;
63 }
64
65 public:
66 //-------------------------- Primitive set operations --------------------------
67
68 void clear() {
69 _map.clear();
70 }
71
72 uint count() const {
73 return _map.count_one_bits();
74 }
75
76 bool is_empty() const {
77 return _map.is_empty();
78 }
79
80 bool member(uint element) const {
81 return _map.at(element);
82 }
83
84 bool insert(uint element) {
85 if (element == 0) {
86 return 0;
87 }
88 return _map.set_bit_with_result(element);
89 }
90
91 bool remove(uint element) {
92 return _map.clear_bit_with_result(element);
93 }
94
95 //------------------------- Construction, initialization -----------------------
96
97 IndexSet() {}
98
99 // This constructor is used for making a deep copy of a IndexSet.
100 IndexSet(IndexSet *set) {
101 _map = BitMap(set->_map.size());
102 _map.set_from(set->_map);
103 };
104
105 // Perform initialization on a IndexSet
106 void initialize(uint max_element) {
107 _map = BitMap(max_element);
108 };
109
110 // Initialize a IndexSet in resource arena.
111 void initialize_in_resource_arena(uint max_element) {
112 _map = BitMap(max_element, true);
113 };
114
115 // Overwrite current IndexSet with another set
116 void set_from(IndexSet *set) {
117 _map.set_from(set->_map);
118 }
119
120 #ifndef PRODUCT
121 void dump();
122 #endif
123 };
124
125
126 //-------------------------------- class IndexSetIterator --------------------
127 // An iterator for IndexSets.
128
129 class IndexSetIterator {
130 friend class IndexSet;
131
132 BitMapIterator iter;
133
134 public:
135 IndexSetIterator(IndexSet *set) : iter(&(set->_map)) {}
136
137 inline uint next() {
138 return iter.next();
139 }
140
141 };
142
143 #endif // SHARE_VM_OPTO_INDEXSET_HPP