1 /*
2 * Copyright (c) 2012, 2017, 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.virtual.phases.ea;
24
25 import java.lang.reflect.Field;
26 import java.util.ArrayList;
27 import java.util.Arrays;
28 import java.util.Iterator;
29
30 import org.graalvm.compiler.debug.Debug;
31 import org.graalvm.compiler.debug.GraalError;
32 import org.graalvm.compiler.graph.Node;
33 import org.graalvm.compiler.nodes.StructuredGraph;
34
35 /**
36 * An {@link EffectList} can be used to maintain a list of {@link Effect}s and backtrack to a
37 * previous state by truncating the list.
38 */
39 public class EffectList implements Iterable<EffectList.Effect> {
40
41 public interface Effect {
42 default boolean isVisible() {
43 return true;
44 }
45
46 default boolean isCfgKill() {
47 return false;
48 }
49
50 void apply(StructuredGraph graph, ArrayList<Node> obsoleteNodes);
51 }
52
53 public interface SimpleEffect extends Effect {
54 @Override
55 default void apply(StructuredGraph graph, ArrayList<Node> obsoleteNodes) {
56 apply(graph);
57 }
58
59 void apply(StructuredGraph graph);
60 }
61
62 private static final Effect[] EMPTY_ARRAY = new Effect[0];
63 private static final String[] EMPTY_STRING_ARRAY = new String[0];
64
65 private Effect[] effects = EMPTY_ARRAY;
66 private String[] names = EMPTY_STRING_ARRAY;
67 private int size;
68
69 private void enlarge(int elements) {
70 int length = effects.length;
71 if (size + elements > length) {
72 while (size + elements > length) {
73 length = Math.max(length * 2, 4);
74 }
75 effects = Arrays.copyOf(effects, length);
76 if (Debug.isEnabled()) {
77 names = Arrays.copyOf(names, length);
78 }
79 }
80 }
81
82 public void add(String name, SimpleEffect effect) {
83 add(name, (Effect) effect);
84 }
85
86 public void add(String name, Effect effect) {
87 assert effect != null;
88 enlarge(1);
89 if (Debug.isEnabled()) {
90 names[size] = name;
91 }
92 effects[size++] = effect;
93 }
94
95 public void addAll(EffectList list) {
96 enlarge(list.size);
97 System.arraycopy(list.effects, 0, effects, size, list.size);
98 if (Debug.isEnabled()) {
99 System.arraycopy(list.names, 0, names, size, list.size);
100 }
101 size += list.size;
102 }
103
104 public void insertAll(EffectList list, int position) {
105 assert position >= 0 && position <= size;
106 enlarge(list.size);
107 System.arraycopy(effects, position, effects, position + list.size, size - position);
108 System.arraycopy(list.effects, 0, effects, position, list.size);
109 if (Debug.isEnabled()) {
110 System.arraycopy(names, position, names, position + list.size, size - position);
111 System.arraycopy(list.names, 0, names, position, list.size);
112 }
113 size += list.size;
114 }
115
116 public int checkpoint() {
117 return size;
118 }
119
120 public int size() {
121 return size;
122 }
123
124 public void backtrack(int checkpoint) {
125 assert checkpoint <= size;
126 size = checkpoint;
127 }
128
129 @Override
130 public Iterator<Effect> iterator() {
131 return new Iterator<Effect>() {
132
133 int index;
134 final int listSize = EffectList.this.size;
135
136 @Override
137 public boolean hasNext() {
138 return index < listSize;
139 }
140
141 @Override
142 public Effect next() {
143 return effects[index++];
144 }
145
146 @Override
147 public void remove() {
148 throw new UnsupportedOperationException();
149 }
150 };
151 }
152
153 public Effect get(int index) {
154 if (index >= size) {
155 throw new IndexOutOfBoundsException();
156 }
157 return effects[index];
158 }
159
160 public void clear() {
161 size = 0;
162 }
163
164 public boolean isEmpty() {
165 return size == 0;
166 }
167
168 public void apply(StructuredGraph graph, ArrayList<Node> obsoleteNodes, boolean cfgKills) {
169 for (int i = 0; i < size(); i++) {
170 Effect effect = effects[i];
171 if (effect.isCfgKill() == cfgKills) {
172 try {
173 effect.apply(graph, obsoleteNodes);
174 } catch (Throwable t) {
175 StringBuilder str = new StringBuilder();
176 toString(str, i);
177 throw new GraalError(t).addContext("effect", str);
178 }
179 if (effect.isVisible() && Debug.isLogEnabled()) {
180 StringBuilder str = new StringBuilder();
181 toString(str, i);
182 Debug.log(" %s", str);
183 }
184 }
185 }
186 }
187
188 private void toString(StringBuilder str, int i) {
189 Effect effect = effects[i];
190 str.append(getName(i)).append(" [");
191 boolean first = true;
192 for (Field field : effect.getClass().getDeclaredFields()) {
193 try {
194 field.setAccessible(true);
195 Object object = field.get(effect);
196 if (object == this) {
197 // Inner classes could capture the EffectList itself.
198 continue;
199 }
200 str.append(first ? "" : ", ").append(format(object));
201 first = false;
202 } catch (SecurityException | IllegalAccessException e) {
203 throw new RuntimeException(e);
204 }
205 }
206 str.append(']');
207 }
208
209 private static String format(Object object) {
210 if (object != null && Object[].class.isAssignableFrom(object.getClass())) {
211 return Arrays.toString((Object[]) object);
212 }
213 return "" + object;
214 }
215
216 @Override
217 public String toString() {
218 StringBuilder str = new StringBuilder();
219 for (int i = 0; i < size(); i++) {
220 Effect effect = get(i);
221 if (effect.isVisible()) {
222 toString(str, i);
223 str.append('\n');
224 }
225 }
226 return str.toString();
227 }
228
229 private String getName(int i) {
230 if (Debug.isEnabled()) {
231 return names[i];
232 } else {
233 return "";
234 }
235 }
236 }