1 /*
2 * Copyright (c) 2010, 2014, 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.runtime;
27
28 import static jdk.nashorn.internal.lookup.Lookup.MH;
29
30 import java.lang.invoke.MethodHandle;
31 import java.lang.invoke.MethodHandles;
32
33 /**
34 * Spill property
35 */
36 public class SpillProperty extends AccessorProperty {
37 private static final long serialVersionUID = 3028496245198669460L;
38
39 private static final MethodHandles.Lookup LOOKUP = MethodHandles.lookup();
40
41 private static final MethodHandle PARRAY_GETTER = MH.asType(MH.getter(LOOKUP, ScriptObject.class, "primitiveSpill", long[].class), MH.type(long[].class, Object.class));
42 private static final MethodHandle OARRAY_GETTER = MH.asType(MH.getter(LOOKUP, ScriptObject.class, "objectSpill", Object[].class), MH.type(Object[].class, Object.class));
43
44 private static final MethodHandle OBJECT_GETTER = MH.filterArguments(MH.arrayElementGetter(Object[].class), 0, OARRAY_GETTER);
45 private static final MethodHandle PRIMITIVE_GETTER = MH.filterArguments(MH.arrayElementGetter(long[].class), 0, PARRAY_GETTER);
46 private static final MethodHandle OBJECT_SETTER = MH.filterArguments(MH.arrayElementSetter(Object[].class), 0, OARRAY_GETTER);
47 private static final MethodHandle PRIMITIVE_SETTER = MH.filterArguments(MH.arrayElementSetter(long[].class), 0, PARRAY_GETTER);
48
49 private static class Accessors {
50 private MethodHandle objectGetter;
51 private MethodHandle objectSetter;
52 private MethodHandle primitiveGetter;
53 private MethodHandle primitiveSetter;
54
55 private final int slot;
56 private final MethodHandle ensureSpillSize;
57
58 private static Accessors ACCESSOR_CACHE[] = new Accessors[512];
59
60 //private static final Map<Integer, Reference<Accessors>> ACCESSOR_CACHE = Collections.synchronizedMap(new WeakHashMap<Integer, Reference<Accessors>>());
61
62 Accessors(final int slot) {
63 assert slot >= 0;
64 this.slot = slot;
65 this.ensureSpillSize = MH.asType(MH.insertArguments(ScriptObject.ENSURE_SPILL_SIZE, 1, slot), MH.type(Object.class, Object.class));
66 }
67
68 private static void ensure(final int slot) {
69 int len = ACCESSOR_CACHE.length;
70 if (slot >= len) {
71 do {
72 len *= 2;
73 } while (slot >= len);
74 final Accessors newCache[] = new Accessors[len];
75 System.arraycopy(ACCESSOR_CACHE, 0, newCache, 0, ACCESSOR_CACHE.length);
76 ACCESSOR_CACHE = newCache;
77 }
78 }
79
80 static MethodHandle getCached(final int slot, final boolean isPrimitive, final boolean isGetter) {
81 //Reference<Accessors> ref = ACCESSOR_CACHE.get(slot);
82 ensure(slot);
83 Accessors acc = ACCESSOR_CACHE[slot];
84 if (acc == null) {
85 acc = new Accessors(slot);
86 ACCESSOR_CACHE[slot] = acc;
87 }
88
89 return acc.getOrCreate(isPrimitive, isGetter);
90 }
91
92 private static MethodHandle primordial(final boolean isPrimitive, final boolean isGetter) {
93 if (isPrimitive) {
94 return isGetter ? PRIMITIVE_GETTER : PRIMITIVE_SETTER;
95 }
96 return isGetter ? OBJECT_GETTER : OBJECT_SETTER;
97 }
98
99 MethodHandle getOrCreate(final boolean isPrimitive, final boolean isGetter) {
100 MethodHandle accessor;
101
102 accessor = getInner(isPrimitive, isGetter);
103 if (accessor != null) {
104 return accessor;
105 }
106
107 accessor = primordial(isPrimitive, isGetter);
108 accessor = MH.insertArguments(accessor, 1, slot);
109 if (!isGetter) {
110 accessor = MH.filterArguments(accessor, 0, ensureSpillSize);
111 }
112 setInner(isPrimitive, isGetter, accessor);
113
114 return accessor;
115 }
116
117 void setInner(final boolean isPrimitive, final boolean isGetter, final MethodHandle mh) {
118 if (isPrimitive) {
119 if (isGetter) {
120 primitiveGetter = mh;
121 } else {
122 primitiveSetter = mh;
123 }
124 } else {
125 if (isGetter) {
126 objectGetter = mh;
127 } else {
128 objectSetter = mh;
129 }
130 }
131 }
132
133 MethodHandle getInner(final boolean isPrimitive, final boolean isGetter) {
134 if (isPrimitive) {
135 return isGetter ? primitiveGetter : primitiveSetter;
136 }
137 return isGetter ? objectGetter : objectSetter;
138 }
139 }
140
141 private static MethodHandle primitiveGetter(final int slot, final int flags) {
142 return (flags & DUAL_FIELDS) == DUAL_FIELDS ? Accessors.getCached(slot, true, true) : null;
143 }
144 private static MethodHandle primitiveSetter(final int slot, final int flags) {
145 return (flags & DUAL_FIELDS) == DUAL_FIELDS ? Accessors.getCached(slot, true, false) : null;
146 }
147 private static MethodHandle objectGetter(final int slot) {
148 return Accessors.getCached(slot, false, true);
149 }
150 private static MethodHandle objectSetter(final int slot) {
151 return Accessors.getCached(slot, false, false);
152 }
153
154 /**
155 * Constructor for spill properties. Array getters and setters will be created on demand.
156 *
157 * @param key the property key
158 * @param flags the property flags
159 * @param slot spill slot
160 */
161 public SpillProperty(final Object key, final int flags, final int slot) {
162 super(key, flags, slot, primitiveGetter(slot, flags), primitiveSetter(slot, flags), objectGetter(slot), objectSetter(slot));
163 }
164
165 /**
166 * Constructor for spill properties with an initial type.
167 * @param key the property key
168 * @param flags the property flags
169 * @param slot spill slot
170 * @param initialType initial type
171 */
172 public SpillProperty(final String key, final int flags, final int slot, final Class<?> initialType) {
173 this(key, flags, slot);
174 setType(hasDualFields() ? initialType : Object.class);
175 }
176
177 SpillProperty(final Object key, final int flags, final int slot, final ScriptObject owner, final Object initialValue) {
178 this(key, flags, slot);
179 setInitialValue(owner, initialValue);
180 }
181
182 /**
183 * Copy constructor
184 * @param property other property
185 */
186 protected SpillProperty(final SpillProperty property) {
187 super(property);
188 }
189
190 /**
191 * Copy constructor
192 * @param newType new type
193 * @param property other property
194 */
195 protected SpillProperty(final SpillProperty property, final Class<?> newType) {
196 super(property, newType);
197 }
198
199 @Override
200 public Property copy() {
201 return new SpillProperty(this);
202 }
203
204 @Override
205 public Property copy(final Class<?> newType) {
206 return new SpillProperty(this, newType);
207 }
208
209 @Override
210 public boolean isSpill() {
211 return true;
212 }
213
214 @Override
215 void initMethodHandles(final Class<?> structure) {
216 final int slot = getSlot();
217 primitiveGetter = primitiveGetter(slot, getFlags());
218 primitiveSetter = primitiveSetter(slot, getFlags());
219 objectGetter = objectGetter(slot);
220 objectSetter = objectSetter(slot);
221 }
222 }