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.runtime.arrays.ArrayIndex.getArrayIndex;
29 import static jdk.nashorn.internal.runtime.arrays.ArrayIndex.isValidArrayIndex;
30
31 import java.util.ArrayList;
32 import java.util.List;
33 import jdk.nashorn.internal.ir.Symbol;
34 import jdk.nashorn.internal.runtime.AccessorProperty;
35 import jdk.nashorn.internal.runtime.Property;
36 import jdk.nashorn.internal.runtime.PropertyMap;
37 import jdk.nashorn.internal.runtime.ScriptObject;
38 import jdk.nashorn.internal.runtime.SpillProperty;
39
40 /**
41 * Class that creates PropertyMap sent to script object constructors.
42 * @param <T> value type for tuples, e.g. Symbol
43 */
44 public class MapCreator<T> {
45 /** Object structure for objects associated with this map */
46 private final Class<?> structure;
47
48 /** key set for object map */
49 private final List<MapTuple<T>> tuples;
50
51 /**
52 * Constructor
53 *
54 * @param structure structure to generate map for (a JO subclass)
55 * @param tuples list of tuples for map
56 */
57 MapCreator(final Class<? extends ScriptObject> structure, final List<MapTuple<T>> tuples) {
58 this.structure = structure;
59 this.tuples = tuples;
60 }
61
62 /**
63 * Constructs a property map based on a set of fields.
64 *
65 * @param hasArguments does the created object have an "arguments" property
66 * @param fieldCount Number of fields in use.
67 * @param fieldMaximum Number of fields available.
68 * @param evalCode is this property map created for 'eval' code?
69 * @return New map populated with accessor properties.
70 */
71 PropertyMap makeFieldMap(final boolean hasArguments, final boolean dualFields, final int fieldCount, final int fieldMaximum, final boolean evalCode) {
72 final List<Property> properties = new ArrayList<>();
73 assert tuples != null;
74
75 for (final MapTuple<T> tuple : tuples) {
76 final String key = tuple.key;
77 final Symbol symbol = tuple.symbol;
78 final Class<?> initialType = dualFields ? tuple.getValueType() : Object.class;
79
80 if (symbol != null && !isValidArrayIndex(getArrayIndex(key))) {
81 final int flags = getPropertyFlags(symbol, hasArguments, evalCode, dualFields);
82 final Property property = new AccessorProperty(
83 key,
84 flags,
85 structure,
86 symbol.getFieldIndex(),
87 initialType);
88 properties.add(property);
89 }
90 }
91
92 return PropertyMap.newMap(properties, structure.getName(), fieldCount, fieldMaximum, 0);
93 }
94
95 PropertyMap makeSpillMap(final boolean hasArguments, final boolean dualFields) {
96 final List<Property> properties = new ArrayList<>();
97 int spillIndex = 0;
98 assert tuples != null;
99
100 for (final MapTuple<T> tuple : tuples) {
101 final String key = tuple.key;
102 final Symbol symbol = tuple.symbol;
103 final Class<?> initialType = dualFields ? tuple.getValueType() : Object.class;
104
105 if (symbol != null && !isValidArrayIndex(getArrayIndex(key))) {
106 final int flags = getPropertyFlags(symbol, hasArguments, false, dualFields);
107 properties.add(
108 new SpillProperty(
109 key,
110 flags,
111 spillIndex++,
112 initialType));
113 }
114 }
115
116 return PropertyMap.newMap(properties, structure.getName(), 0, 0, spillIndex);
117 }
118
119 /**
120 * Compute property flags given local state of a field. May be overridden and extended,
121 *
122 * @param symbol symbol to check
123 * @param hasArguments does the created object have an "arguments" property
124 *
125 * @return flags to use for fields
126 */
127 static int getPropertyFlags(final Symbol symbol, final boolean hasArguments, final boolean evalCode, final boolean dualFields) {
128 int flags = 0;
129
130 if (symbol.isParam()) {
131 flags |= Property.IS_PARAMETER;
132 }
133
134 if (hasArguments) {
135 flags |= Property.HAS_ARGUMENTS;
136 }
137
138 // See ECMA 5.1 10.5 Declaration Binding Instantiation.
139 // Step 2 If code is eval code, then let configurableBindings
140 // be true else let configurableBindings be false.
141 // We have to make vars, functions declared in 'eval' code
142 // configurable. But vars, functions from any other code is
143 // not configurable.
144 if (symbol.isScope() && !evalCode) {
145 flags |= Property.NOT_CONFIGURABLE;
146 }
147
148 if (symbol.isFunctionDeclaration()) {
149 flags |= Property.IS_FUNCTION_DECLARATION;
150 }
151
152 if (symbol.isConst()) {
153 flags |= Property.NOT_WRITABLE;
154 }
155
156 if (symbol.isBlockScoped()) {
157 flags |= Property.IS_LEXICAL_BINDING;
158 }
159
160 // Mark symbol as needing declaration. Access before declaration will throw a ReferenceError.
161 if (symbol.isBlockScoped() && symbol.isScope()) {
162 flags |= Property.NEEDS_DECLARATION;
163 }
164
165 if (dualFields) {
166 flags |= Property.DUAL_FIELDS;
167 }
168
169 return flags;
170 }
171 }