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); 171 172 method.putField(fieldClass, fieldName, fieldDesc); 173 } 174 175 /** 176 * Store a value in an indexed slot of a generated class object. 177 * 178 * @param method Script method. 179 * @param index Slot index. 180 * @param tuple Tuple to store. 181 */ 182 private void putSlot(final MethodEmitter method, final long index, final MapTuple<T> tuple) { 183 if (JSType.isRepresentableAsInt(index)) { 184 method.load((int)index); 185 } else { 186 method.load(index); 187 } 188 loadTuple(method, tuple, false); //we don't pack array like objects 189 method.dynamicSetIndex(callSiteFlags); 190 } 191 192 /** 193 * Locate (or indirectly create) the object container class. 194 */ 195 private void findClass() { 196 fieldObjectClassName = isScope() ? 197 ObjectClassGenerator.getClassName(fieldCount, paramCount, codegen.useDualFields()) : 198 ObjectClassGenerator.getClassName(paddedFieldCount, codegen.useDualFields()); 199 200 try { 201 this.fieldObjectClass = Context.forStructureClass(Compiler.binaryName(fieldObjectClassName)); 202 } catch (final ClassNotFoundException e) { 203 throw new AssertionError("Nashorn has encountered an internal error. Structure can not be created."); 204 } 205 } 206 207 @Override 208 protected Class<? extends ScriptObject> getAllocatorClass() { 209 return fieldObjectClass; 210 } 211 212 /** 213 * Get the class name for the object class, 214 * e.g. {@code com.nashorn.oracle.scripts.JO2P0} 215 * 216 * @return script class name 217 */ 218 String getClassName() { 219 return fieldObjectClassName; 220 } 221 222 /** 223 * Tally the number of fields and parameters. 224 */ 225 private void countFields() { 226 for (final MapTuple<T> tuple : tuples) { 227 final Symbol symbol = tuple.symbol; 228 if (symbol != null) { 229 if (hasArguments() && symbol.isParam()) { 230 symbol.setFieldIndex(paramCount++); 231 } else if (!isValidArrayIndex(getArrayIndex(tuple.key))) { 232 symbol.setFieldIndex(fieldCount++); 233 } 234 } 235 } 236 237 paddedFieldCount = getPaddedFieldCount(fieldCount); 238 } 239 240 }