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.ARGUMENTS;
29 import static jdk.nashorn.internal.codegen.CompilerConstants.constructorNoLookup;
30 import static jdk.nashorn.internal.codegen.CompilerConstants.typeDescriptor;
31 import static jdk.nashorn.internal.codegen.ObjectClassGenerator.PRIMITIVE_FIELD_TYPE;
32 import static jdk.nashorn.internal.codegen.ObjectClassGenerator.getFieldName;
33 import static jdk.nashorn.internal.codegen.ObjectClassGenerator.getPaddedFieldCount;
34 import static jdk.nashorn.internal.runtime.arrays.ArrayIndex.getArrayIndex;
35 import static jdk.nashorn.internal.runtime.arrays.ArrayIndex.isValidArrayIndex;
36
37 import java.util.List;
38 import jdk.nashorn.internal.codegen.types.Type;
39 import jdk.nashorn.internal.ir.Symbol;
40 import jdk.nashorn.internal.runtime.Context;
41 import jdk.nashorn.internal.runtime.JSType;
42 import jdk.nashorn.internal.runtime.PropertyMap;
43 import jdk.nashorn.internal.runtime.ScriptObject;
44 import jdk.nashorn.internal.runtime.arrays.ArrayIndex;
45
46 /**
47 * Analyze an object's characteristics for appropriate code generation. This
48 * is used for functions and for objects. A field object take a set of values which
49 * to assign to the various fields in the object. This is done by the generated code
50 *
51 * @param <T> the value type for the fields being written on object creation, e.g. Node
52 * @see jdk.nashorn.internal.ir.Node
53 */
54 public abstract class FieldObjectCreator<T> extends ObjectCreator<T> {
55
56 private String fieldObjectClassName;
57 private Class<? extends ScriptObject> fieldObjectClass;
58 private int fieldCount;
59 private int paddedFieldCount;
60 private int paramCount;
61
62 /** call site flags to be used for invocations */
63 private final int callSiteFlags;
64 /** are we creating this field object from 'eval' code? */
65 private final boolean evalCode;
66
67 /**
68 * Constructor
69 *
70 * @param codegen code generator
71 * @param tuples tuples for fields in object
72 */
73 FieldObjectCreator(final CodeGenerator codegen, final List<MapTuple<T>> tuples) {
74 this(codegen, tuples, false, false);
75 }
76
77 /**
78 * Constructor
79 *
80 * @param codegen code generator
81 * @param tuples tuples for fields in object
82 * @param isScope is this a scope object
83 * @param hasArguments does the created object have an "arguments" property
84 */
85 FieldObjectCreator(final CodeGenerator codegen, final List<MapTuple<T>> tuples, final boolean isScope, final boolean hasArguments) {
86 super(codegen, tuples, isScope, hasArguments);
87 this.callSiteFlags = codegen.getCallSiteFlags();
88 this.evalCode = codegen.isEvalCode();
89 countFields();
90 findClass();
91 }
92
93 @Override
94 public void createObject(final MethodEmitter method) {
95 makeMap();
96 final String className = getClassName();
97 // NOTE: we must load the actual structure class here, because the API operates with Nashorn Type objects,
98 // and Type objects need a loaded class, for better or worse. We also have to be specific and use the type
99 // of the actual structure class, we can't generalize it to e.g. Type.typeFor(ScriptObject.class) as the
100 // exact type information is needed for generating continuations in rest-of methods. If we didn't do this,
101 // object initializers like { x: arr[i] } would fail during deoptimizing compilation on arr[i], as the
102 // values restored from the RewriteException would be cast to "ScriptObject" instead of to e.g. "JO4", and
103 // subsequently the "PUTFIELD J04.L0" instruction in the continuation code would fail bytecode verification.
104 assert fieldObjectClass != null;
105 method._new(fieldObjectClass).dup();
106
107 loadMap(method); //load the map
108
109 if (isScope()) {
110 loadScope(method);
111
112 if (hasArguments()) {
113 method.loadCompilerConstant(ARGUMENTS);
114 method.invoke(constructorNoLookup(className, PropertyMap.class, ScriptObject.class, ARGUMENTS.type()));
115 } else {
116 method.invoke(constructorNoLookup(className, PropertyMap.class, ScriptObject.class));
117 }
118 } else {
119 method.invoke(constructorNoLookup(className, PropertyMap.class));
120 }
121 }
122
123 @Override
124 public void populateRange(final MethodEmitter method, final Type objectType, final int objectSlot, final int start, final int end) {
125 method.load(objectType, objectSlot);
126 // Set values.
127 for (int i = start; i < end; i++) {
128 final MapTuple<T> tuple = tuples.get(i);
129 //we only load when we have both symbols and values (which can be == the symbol)
130 //if we didn't load, we need an array property
131 if (tuple.symbol != null && tuple.value != null) {
132 final int index = getArrayIndex(tuple.key);
133 method.dup();
134 if (!isValidArrayIndex(index)) {
135 putField(method, tuple.key, tuple.symbol.getFieldIndex(), tuple);
136 } else {
137 putSlot(method, ArrayIndex.toLongIndex(index), tuple);
138 }
139
140 //this is a nop of tuple.key isn't e.g. "apply" or another special name
141 method.invalidateSpecialName(tuple.key);
142 }
143 }
144 }
145
146 @Override
147 protected PropertyMap makeMap() {
148 assert propertyMap == null : "property map already initialized";
149 propertyMap = newMapCreator(fieldObjectClass).makeFieldMap(hasArguments(), codegen.useDualFields(), fieldCount, paddedFieldCount, evalCode);
150 return propertyMap;
151 }
152
153 /**
154 * Store a value in a field of the generated class object.
155 *
156 * @param method Script method.
157 * @param key Property key.
158 * @param fieldIndex Field number.
159 * @param tuple Tuple to store.
160 */
161 private void putField(final MethodEmitter method, final String key, final int fieldIndex, final MapTuple<T> tuple) {
162 final Type fieldType = codegen.useDualFields() && tuple.isPrimitive() ? PRIMITIVE_FIELD_TYPE : Type.OBJECT;
163 final String fieldClass = getClassName();
164 final String fieldName = getFieldName(fieldIndex, fieldType);
165 final String fieldDesc = typeDescriptor(fieldType.getTypeClass());
166
167 assert fieldName.equals(getFieldName(fieldIndex, PRIMITIVE_FIELD_TYPE)) || fieldType.isObject() : key + " object keys must store to L*-fields";
168 assert fieldName.equals(getFieldName(fieldIndex, Type.OBJECT)) || fieldType.isPrimitive() : key + " primitive keys must store to J*-fields";
169
170 loadTuple(method, tuple, true);
171 method.putField(fieldClass, fieldName, fieldDesc);
172 }
173
174 /**
175 * Store a value in an indexed slot of a generated class object.
176 *
177 * @param method Script method.
178 * @param index Slot index.
179 * @param tuple Tuple to store.
180 */
181 private void putSlot(final MethodEmitter method, final long index, final MapTuple<T> tuple) {
182 loadIndex(method, index);
183 loadTuple(method, tuple, false); //we don't pack array like objects
184 method.dynamicSetIndex(callSiteFlags);
185 }
186
187 /**
188 * Locate (or indirectly create) the object container class.
189 */
190 private void findClass() {
191 fieldObjectClassName = isScope() ?
192 ObjectClassGenerator.getClassName(fieldCount, paramCount, codegen.useDualFields()) :
193 ObjectClassGenerator.getClassName(paddedFieldCount, codegen.useDualFields());
194
195 try {
196 this.fieldObjectClass = Context.forStructureClass(Compiler.binaryName(fieldObjectClassName));
197 } catch (final ClassNotFoundException e) {
198 throw new AssertionError("Nashorn has encountered an internal error. Structure can not be created.");
199 }
200 }
201
202 @Override
203 protected Class<? extends ScriptObject> getAllocatorClass() {
204 return fieldObjectClass;
205 }
206
207 /**
208 * Get the class name for the object class,
209 * e.g. {@code com.nashorn.oracle.scripts.JO2P0}
210 *
211 * @return script class name
212 */
213 String getClassName() {
214 return fieldObjectClassName;
215 }
216
217 /**
218 * Tally the number of fields and parameters.
219 */
220 private void countFields() {
221 for (final MapTuple<T> tuple : tuples) {
222 final Symbol symbol = tuple.symbol;
223 if (symbol != null) {
224 if (hasArguments() && symbol.isParam()) {
225 symbol.setFieldIndex(paramCount++);
226 } else if (!isValidArrayIndex(getArrayIndex(tuple.key))) {
227 symbol.setFieldIndex(fieldCount++);
228 }
229 }
230 }
231
232 paddedFieldCount = getPaddedFieldCount(fieldCount);
233 }
234
235 }