1 /*
2 * Copyright (c) 2010, 2013, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package jdk.nashorn.internal.codegen;
27
28 import java.io.Serializable;
29 import java.util.Collection;
30 import java.util.Collections;
31 import java.util.IdentityHashMap;
32 import java.util.Map;
33 import java.util.Objects;
34 import java.util.Set;
35 import java.util.TreeSet;
36 import jdk.nashorn.internal.ir.CompileUnitHolder;
37 import jdk.nashorn.internal.ir.FunctionNode;
38 import jdk.nashorn.internal.runtime.RecompilableScriptFunctionData;
39
40 /**
41 * Used to track split class compilation. Note that instances of the class are serializable, but all fields are
42 * transient, making the serialized version of the class only useful for tracking the referential topology of other
43 * AST nodes referencing the same or different compile units. We do want to preserve this topology though as
44 * {@link CompileUnitHolder}s in a deserialized AST will undergo reinitialization.
45 */
46 public final class CompileUnit implements Comparable<CompileUnit>, Serializable {
47 private static final long serialVersionUID = 1L;
48
49 /** Current class name */
50 private transient final String className;
51
52 /** Current class generator */
53 private transient ClassEmitter classEmitter;
54
55 private transient long weight;
56
57 private transient Class<?> clazz;
58
59 private final transient Map<FunctionNode, RecompilableScriptFunctionData> functions = new IdentityHashMap<>();
60
61 private transient boolean isUsed;
62
63 private static int emittedUnitCount;
64
65 CompileUnit(final String className, final ClassEmitter classEmitter, final long initialWeight) {
66 this.className = className;
67 this.weight = initialWeight;
68 this.classEmitter = classEmitter;
69 }
70
71 static Set<CompileUnit> createCompileUnitSet() {
72 return new TreeSet<>();
73 }
74
75 static void increaseEmitCount() {
76 emittedUnitCount++;
77 }
78
79 /**
80 * Get the amount of emitted compile units so far in the system
81 * @return emitted compile unit count
82 */
83 public static int getEmittedUnitCount() {
84 return emittedUnitCount;
85 }
86
87 /**
88 * Check if this compile unit is used
89 * @return true if tagged as in use - i.e active code that needs to be generated
90 */
91 public boolean isUsed() {
92 return isUsed;
93 }
94
95 /**
96 * Check if a compile unit has code, not counting inits and clinits
97 * @return true of if there is "real code" in the compile unit
98 */
99 public boolean hasCode() {
100 return (classEmitter.getMethodCount() - classEmitter.getInitCount() - classEmitter.getClinitCount()) > 0;
101 }
102
103 /**
104 * Tag this compile unit as used
105 */
106 public void setUsed() {
107 this.isUsed = true;
108 }
109
110 /**
111 * Return the class that contains the code for this unit, null if not
112 * generated yet
113 *
114 * @return class with compile unit code
115 */
116 public Class<?> getCode() {
117 return clazz;
118 }
119
120 /**
121 * Set class when it exists. Only accessible from compiler
122 * @param clazz class with code for this compile unit
123 */
124 void setCode(final Class<?> clazz) {
125 this.clazz = Objects.requireNonNull(clazz);
126 // Revisit this - refactor to avoid null-ed out non-final fields
127 // null out emitter
128 this.classEmitter = null;
129 }
130
131 void addFunctionInitializer(final RecompilableScriptFunctionData data, final FunctionNode functionNode) {
132 functions.put(functionNode, data);
133 }
134
135 /**
136 * Returns true if this compile unit is responsible for initializing the specified function data with specified
137 * function node.
138 * @param data the function data to check
139 * @param functionNode the function node to check
140 * @return true if this unit is responsible for initializing the function data with the function node, otherwise
141 * false
142 */
143 public boolean isInitializing(final RecompilableScriptFunctionData data, final FunctionNode functionNode) {
144 return functions.get(functionNode) == data;
145 }
146
147 void initializeFunctionsCode() {
148 for(final Map.Entry<FunctionNode, RecompilableScriptFunctionData> entry : functions.entrySet()) {
149 entry.getValue().initializeCode(entry.getKey());
150 }
151 }
152
153 Collection<FunctionNode> getFunctionNodes() {
154 return Collections.unmodifiableCollection(functions.keySet());
155 }
156
157 /**
158 * Add weight to this compile unit
159 * @param w weight to add
160 */
161 void addWeight(final long w) {
162 this.weight += w;
163 }
164
165 /**
166 * Check if this compile unit can hold {@code weight} more units of weight
167 * @param w weight to check if can be added
168 * @return true if weight fits in this compile unit
169 */
170 public boolean canHold(final long w) {
171 return (this.weight + w) < Splitter.SPLIT_THRESHOLD;
172 }
173
174 /**
175 * Get the class emitter for this compile unit
176 * @return class emitter
177 */
178 public ClassEmitter getClassEmitter() {
179 return classEmitter;
180 }
181
182 /**
183 * Get the class name for this compile unit
184 * @return the class name
185 */
186 public String getUnitClassName() {
187 return className;
188 }
189
190 private static String shortName(final String name) {
191 return name == null ? null : name.lastIndexOf('/') == -1 ? name : name.substring(name.lastIndexOf('/') + 1);
192 }
193
194 @Override
195 public String toString() {
196 final String methods = classEmitter != null ? classEmitter.getMethodNames().toString() : "<anon>";
197 return "[CompileUnit className=" + shortName(className) + " weight=" + weight + '/' + Splitter.SPLIT_THRESHOLD + " hasCode=" + methods + ']';
198 }
199
200 @Override
201 public int compareTo(final CompileUnit o) {
202 return className.compareTo(o.className);
203 }
204 }