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 static jdk.nashorn.internal.codegen.CompilerConstants.SCOPE;
29
30 import java.util.List;
31 import jdk.nashorn.internal.codegen.types.Type;
32 import jdk.nashorn.internal.runtime.JSType;
33 import jdk.nashorn.internal.runtime.PropertyMap;
34 import jdk.nashorn.internal.runtime.ScriptObject;
35
36 /**
37 * Base class for object creation code generation.
38 * @param <T> value type
39 */
40 public abstract class ObjectCreator<T> implements CodeGenerator.SplitLiteralCreator {
41
42 /** List of keys & symbols to initiate in this ObjectCreator */
43 final List<MapTuple<T>> tuples;
44
45 /** Code generator */
46 final CodeGenerator codegen;
47
48 /** Property map */
49 protected PropertyMap propertyMap;
50
51 private final boolean isScope;
52 private final boolean hasArguments;
53
54 /**
55 * Constructor
56 *
57 * @param codegen the code generator
58 * @param tuples key,symbol,value (optional) tuples
59 * @param isScope is this object scope
60 * @param hasArguments does the created object have an "arguments" property
61 */
62 ObjectCreator(final CodeGenerator codegen, final List<MapTuple<T>> tuples, final boolean isScope, final boolean hasArguments) {
63 this.codegen = codegen;
64 this.tuples = tuples;
65 this.isScope = isScope;
66 this.hasArguments = hasArguments;
67 }
68
69 /**
70 * Generate code for making the object.
71 * @param method Script method.
72 */
73 public void makeObject(final MethodEmitter method) {
74 createObject(method);
75 // We need to store the object in a temporary slot as populateRange expects to load the
76 // object from a slot (as it is also invoked within split methods). Note that this also
77 // helps optimistic continuations to handle the stack in case an optimistic assumption
78 // fails during initialization (see JDK-8079269).
79 final int objectSlot = method.getUsedSlotsWithLiveTemporaries();
80 final Type objectType = method.peekType();
81 method.storeTemp(objectType, objectSlot);
82 populateRange(method, objectType, objectSlot, 0, tuples.size());
83 }
84
85 /**
86 * Generate code for creating and initializing the object.
87 * @param method the method emitter
88 */
89 protected abstract void createObject(final MethodEmitter method);
90
91 /**
92 * Construct the property map appropriate for the object.
93 * @return the newly created property map
94 */
95 protected abstract PropertyMap makeMap();
96
97 /**
98 * Create a new MapCreator
99 * @param clazz type of MapCreator
100 * @return map creator instantiated by type
101 */
102 protected MapCreator<?> newMapCreator(final Class<? extends ScriptObject> clazz) {
103 return new MapCreator<>(clazz, tuples);
104 }
105
106 /**
107 * Loads the scope on the stack through the passed method emitter.
108 * @param method the method emitter to use
109 */
110 protected void loadScope(final MethodEmitter method) {
111 method.loadCompilerConstant(SCOPE);
112 }
113
114 /**
115 * Emit the correct map for the object.
116 * @param method method emitter
117 * @return the method emitter
118 */
119 protected MethodEmitter loadMap(final MethodEmitter method) {
120 codegen.loadConstant(propertyMap);
121 return method;
122 }
123
124 PropertyMap getMap() {
125 return propertyMap;
126 }
127
128 /**
129 * Is this a scope object
130 * @return true if scope
131 */
132 protected boolean isScope() {
133 return isScope;
134 }
135
136 /**
137 * Does the created object have an "arguments" property
138 * @return true if has an "arguments" property
139 */
140 protected boolean hasArguments() {
141 return hasArguments;
142 }
143
144 /**
145 * Get the class of objects created by this ObjectCreator
146 * @return class of created object
147 */
148 abstract protected Class<? extends ScriptObject> getAllocatorClass();
149
150 /**
151 * Technique for loading an initial value. Defined by anonymous subclasses in code gen.
152 *
153 * @param value Value to load.
154 * @param type the type of the value to load
155 */
156 protected abstract void loadValue(T value, Type type);
157
158 MethodEmitter loadTuple(final MethodEmitter method, final MapTuple<T> tuple, final boolean pack) {
159 loadValue(tuple.value, tuple.type);
160 if (!codegen.useDualFields() || !tuple.isPrimitive()) {
161 method.convert(Type.OBJECT);
162 } else if (pack) {
163 method.pack();
164 }
165 return method;
166 }
167
168 MethodEmitter loadIndex(final MethodEmitter method, final long index) {
169 return JSType.isRepresentableAsInt(index) ? method.load((int) index) : method.load((double) index);
170 }
171 }