1 /*
2 * Copyright (c) 2011, 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 package org.graalvm.compiler.graph;
24
25 import java.util.Arrays;
26 import java.util.Iterator;
27
28 import org.graalvm.compiler.graph.iterators.NodeIterable;
29
30 public final class NodeBitMap implements NodeIterable<Node> {
31 private static final int SHIFT = 6;
32
33 private long[] bits;
34 private int nodeCount;
35 private int counter;
36 private final Graph graph;
37
38 public NodeBitMap(Graph graph) {
39 this.nodeCount = graph.nodeIdCount();
40 this.bits = new long[sizeForNodeCount(nodeCount)];
41 this.graph = graph;
42 }
43
44 private static int sizeForNodeCount(int nodeCount) {
45 return (nodeCount + Long.SIZE - 1) >> SHIFT;
46 }
47
48 public int getCounter() {
49 return counter;
50 }
51
52 private NodeBitMap(NodeBitMap other) {
53 this.bits = other.bits.clone();
54 this.nodeCount = other.nodeCount;
55 this.graph = other.graph;
56 }
57
58 public Graph graph() {
59 return graph;
60 }
61
62 public boolean isNew(Node node) {
63 return node.id() >= nodeCount;
64 }
65
66 public boolean isMarked(Node node) {
67 assert check(node, false);
68 return isMarked(node.id());
69 }
70
71 public boolean checkAndMarkInc(Node node) {
72 if (!isMarked(node)) {
73 this.counter++;
74 this.mark(node);
75 return true;
76 } else {
77 return false;
78 }
79 }
80
81 public boolean isMarked(int id) {
82 return (bits[id >> SHIFT] & (1L << id)) != 0;
83 }
84
85 public boolean isMarkedAndGrow(Node node) {
86 assert check(node, true);
87 int id = node.id();
88 checkGrow(id);
89 return isMarked(id);
90 }
91
92 public void mark(Node node) {
93 assert check(node, false);
94 int id = node.id();
95 bits[id >> SHIFT] |= (1L << id);
96 }
97
98 public void markAndGrow(Node node) {
99 assert check(node, true);
100 int id = node.id();
101 checkGrow(id);
102 bits[id >> SHIFT] |= (1L << id);
103 }
104
105 public void clear(Node node) {
106 assert check(node, false);
107 int id = node.id();
108 bits[id >> SHIFT] &= ~(1L << id);
109 }
110
111 public void clearAndGrow(Node node) {
112 assert check(node, true);
113 int id = node.id();
114 checkGrow(id);
115 bits[id >> SHIFT] &= ~(1L << id);
116 }
117
118 private void checkGrow(int id) {
119 if (id >= nodeCount) {
120 if ((id >> SHIFT) >= bits.length) {
121 grow();
122 } else {
123 nodeCount = id + 1;
124 }
125 }
126 }
127
128 public void clearAll() {
129 Arrays.fill(bits, 0);
130 }
131
132 public void intersect(NodeBitMap other) {
133 assert graph() == other.graph();
134 int commonLength = Math.min(bits.length, other.bits.length);
135 for (int i = commonLength; i < bits.length; i++) {
136 bits[i] = 0;
137 }
138 for (int i = 0; i < commonLength; i++) {
139 bits[i] &= other.bits[i];
140 }
141 }
142
143 public void subtract(NodeBitMap other) {
144 assert graph() == other.graph();
145 int commonLength = Math.min(bits.length, other.bits.length);
146 for (int i = 0; i < commonLength; i++) {
147 bits[i] &= ~other.bits[i];
148 }
149 }
150
151 public void union(NodeBitMap other) {
152 assert graph() == other.graph();
153 grow();
154 if (bits.length < other.bits.length) {
155 bits = Arrays.copyOf(bits, other.bits.length);
156 }
157 for (int i = 0; i < bits.length; i++) {
158 bits[i] |= other.bits[i];
159 }
160 }
161
162 public void grow() {
163 nodeCount = Math.max(nodeCount, graph().nodeIdCount());
164 int newLength = sizeForNodeCount(nodeCount);
165 if (newLength > bits.length) {
166 newLength = Math.max(newLength, (bits.length * 3 / 2) + 1);
167 bits = Arrays.copyOf(bits, newLength);
168 }
169 }
170
171 private boolean check(Node node, boolean grow) {
172 assert node.graph() == graph() : "this node is not part of the graph: " + node;
173 assert grow || !isNew(node) : "node was added to the graph after creating the node bitmap: " + node;
174 assert node.isAlive() : "node is deleted!" + node;
175 return true;
176 }
177
178 public <T extends Node> void markAll(Iterable<T> nodes) {
179 for (Node node : nodes) {
180 mark(node);
181 }
182 }
183
184 private static class MarkedNodeIterator implements Iterator<Node> {
185
186 private final NodeBitMap visited;
187 private Iterator<Node> nodes;
188 private Node nextNode;
189
190 MarkedNodeIterator(NodeBitMap visited, Iterator<Node> nodes) {
191 this.visited = visited;
192 this.nodes = nodes;
193 forward();
194 }
195
196 private void forward() {
197 do {
198 if (!nodes.hasNext()) {
199 nextNode = null;
200 return;
201 }
202 nextNode = nodes.next();
203 if (visited.isNew(nextNode)) {
204 nextNode = null;
205 return;
206 }
207 } while (!visited.isMarked(nextNode));
208 }
209
210 @Override
211 public boolean hasNext() {
212 return nextNode != null;
213 }
214
215 @Override
216 public Node next() {
217 try {
218 return nextNode;
219 } finally {
220 forward();
221 }
222 }
223
224 @Override
225 public void remove() {
226 throw new UnsupportedOperationException();
227 }
228
229 }
230
231 @Override
232 public Iterator<Node> iterator() {
233 return new MarkedNodeIterator(NodeBitMap.this, graph().getNodes().iterator());
234 }
235
236 public NodeBitMap copy() {
237 return new NodeBitMap(this);
238 }
239
240 @Override
241 public int count() {
242 int count = 0;
243 for (long l : bits) {
244 count += Long.bitCount(l);
245 }
246 return count;
247 }
248
249 @Override
250 public boolean contains(Node node) {
251 return isMarked(node);
252 }
253
254 @Override
255 public String toString() {
256 return snapshot().toString();
257 }
258 }