1 /*
2 * Copyright (c) 2016, 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.experimental.value;
27
28 import java.lang.invoke.MethodHandle;
29 import java.lang.invoke.MethodHandles;
30 import java.lang.invoke.MethodHandles.Lookup;
31 import java.lang.invoke.MethodType;
32 import java.lang.reflect.Field;
33 import java.lang.reflect.Method;
34 import java.lang.reflect.Modifier;
35 import java.util.Arrays;
36 import java.util.List;
37 import java.util.Map;
38 import java.util.Objects;
39 import java.util.Optional;
40 import java.util.concurrent.ConcurrentHashMap;
41 import java.util.stream.Stream;
42
43 import jdk.experimental.value.ValueType.ValueHandleKind.ValueHandleKey;
44 import jdk.experimental.bytecode.MacroCodeBuilder.CondKind;
45 import jdk.experimental.bytecode.TypeTag;
46 import jdk.internal.misc.Unsafe;
47 import sun.invoke.util.BytecodeDescriptor;
48 import sun.invoke.util.Wrapper;
49 import valhalla.shady.MinimalValueTypes_1_0;
50
51 // Rough place holder just now...
52 public class ValueType<T> {
53
54 static final Unsafe UNSAFE = Unsafe.getUnsafe();
55
56 enum ValueHandleKind {
57 BOX,
58 UNBOX,
59 DEFAULT,
60 EQ,
61 HASH,
62 WITHER() {
63 @Override
64 ValueHandleKey key(Object fieldName) {
65 return new ValueHandleKey(this, fieldName);
66 }
67 },
68 NEWARRAY,
69 VALOAD,
70 VASTORE,
71 MULTINEWARRAY() {
72 @Override
73 ValueHandleKey key(Object dims) {
74 return new ValueHandleKey(this, dims);
75 }
76 },
77 IDENTITY,
78 GETTER() {
79 @Override
80 ValueHandleKey key(Object fieldName) {
81 return new ValueHandleKey(this, fieldName);
82 }
83 };
84
85 ValueHandleKey key() {
86 return new ValueHandleKey(this, null);
87 }
88
89 ValueHandleKey key(Object optArg) {
90 throw new IllegalStateException();
91 }
92
93 static class ValueHandleKey {
94 ValueHandleKind kind;
95 Optional<Object> optArg;
96
97 ValueHandleKey(ValueHandleKind kind, Object optArg) {
98 this.kind = kind;
99 this.optArg = Optional.ofNullable(optArg);
100 }
101
102 @Override
103 public boolean equals(Object obj) {
104 if (obj instanceof ValueHandleKey) {
105 ValueHandleKey that = (ValueHandleKey)obj;
106 return Objects.equals(kind, that.kind) &&
107 Objects.equals(optArg, that.optArg);
108 } else {
109 return false;
110 }
111 }
112
113 @Override
114 public int hashCode() {
115 return Objects.hashCode(kind) * 31 + Objects.hashCode(optArg);
116 }
117 }
118 }
119
120 private static final Lookup IMPL_LOOKUP;
121
122 static {
123 try {
124 Field f = Lookup.class.getDeclaredField("IMPL_LOOKUP");
125 f.setAccessible(true);
126 IMPL_LOOKUP = (Lookup)f.get(null);
127 } catch (ReflectiveOperationException ex) {
128 throw new AssertionError(ex);
129 }
130 }
131
132 private static final ConcurrentHashMap<Class<?>, ValueType<?>> BOX_TO_VT = new ConcurrentHashMap<>();
133
134 public static boolean classHasValueType(Class<?> x) {
135 return MinimalValueTypes_1_0.classHasValueType(x);
136 }
137
138 @SuppressWarnings("unchecked")
139 public static <T> ValueType<T> forClass(Class<T> x) {
140 ValueType<T> vt = (ValueType<T>) BOX_TO_VT.get(x);
141 if (vt != null) {
142 return vt;
143 }
144
145 try {
146 Class<T> valueClass = (Class<T>) MinimalValueTypes_1_0.getValueTypeClass(x);
147 vt = new ValueType<T>(x, valueClass);
148 ValueType<T> old = (ValueType<T>) BOX_TO_VT.putIfAbsent(x, vt);
149 if (old != null) {
150 vt = old;
151 }
152 return vt;
153 }
154 catch (ClassNotFoundException cne) {
155 throw new IllegalArgumentException("Class " + x + " not bound to ValueType", cne);
156 }
157 }
158
159 private Lookup boxLookup;
160 private Lookup valueLookup;
161 private Map<ValueHandleKind.ValueHandleKey, MethodHandle> handleMap = new ConcurrentHashMap<>();
162
163 private ValueType(Class<T> boxClass, Class<T> valueClass) {
164 this.boxLookup = IMPL_LOOKUP.in(boxClass);
165 this.valueLookup = IMPL_LOOKUP.in(valueClass);
166 }
167
168 @SuppressWarnings("unchecked")
169 public Class<T> boxClass() {
170 return (Class<T>)boxLookup.lookupClass();
171 }
172
173 public Class<?> sourceClass() {
174 return boxClass();
175 }
176
177 public Class<?> valueClass() {
178 return valueLookup.lookupClass();
179 }
180
181 public Class<?> arrayValueClass() {
182 return arrayValueClass(1);
183 }
184
185 public Class<?> arrayValueClass(int dims) {
186 try {
187 String dimsStr = "[[[[[[[[[[[[[[[[";
188 if (dims < 1 || dims > 16) {
189 throw new IllegalArgumentException("cannot create array class for dimension > 16");
190 }
191 return Class.forName(dimsStr.substring(0, dims) + "Q" + valueClass().getName() + ";", false, boxLookup.lookupClass().getClassLoader());
192 } catch (ClassNotFoundException ex) {
193 throw new IllegalStateException(ex);
194 }
195 }
196
197 public String toString() {
198 return "ValueType boxClass=" + boxClass() + " valueClass=" + valueClass();
199 }
200
201 String mhName(String opName) {
202 return sourceClass().getName() + "_" + opName;
203 }
204
205 public MethodHandle defaultValueConstant() {
206 ValueHandleKey key = ValueHandleKind.DEFAULT.key();
207 MethodHandle result = handleMap.get(key);
208 if (result == null) {
209 result = MethodHandleBuilder.loadCode(boxLookup, mhName("default"), MethodType.methodType(valueClass()),
210 C -> {
211 C.vdefault(valueClass()).vreturn();
212 });
213 handleMap.put(key, result);
214 }
215 return result;
216 }
217
218 public MethodHandle substitutabilityTest() {
219 ValueHandleKey key = ValueHandleKind.EQ.key();
220 MethodHandle result = handleMap.get(key);
221 if (result == null) {
222 result = MethodHandleBuilder.loadCode(valueLookup, mhName("subTest"), MethodType.methodType(boolean.class, valueClass(), valueClass()),
223 C -> {
224 for (Field f : valueFields()) {
225 String fDesc = BytecodeDescriptor.unparse(f.getType());
226 C.vload(0).vgetfield(valueClass(), f.getName(), fDesc);
227 C.vload(1).vgetfield(valueClass(), f.getName(), fDesc);
228 if (f.getType().isPrimitive()) {
229 C.ifcmp(fDesc, CondKind.NE, "fail");
230 } else {
231 C.invokestatic(Objects.class, "equals", "(Ljava/lang/Object;Ljava/lang/Object;)Z", false);
232 C.const_(0).ifcmp(TypeTag.I, CondKind.EQ, "fail");
233 }
234 }
235 C.const_(1);
236 C.ireturn();
237 C.label("fail");
238 C.const_(0);
239 C.ireturn();
240 });
241 handleMap.put(key, result);
242 }
243 return result;
244 }
245
246 public MethodHandle substitutabilityHashCode() {
247 ValueHandleKey key = ValueHandleKind.HASH.key();
248 MethodHandle result = handleMap.get(key);
249 if (result == null) {
250 result = MethodHandleBuilder.loadCode(valueLookup, mhName("subHash"), MethodType.methodType(int.class, valueClass()),
251 C -> {
252 C.withLocal("res", "I");
253 C.const_(1).store("res");
254 for (Field f : valueFields()) {
255 String desc = BytecodeDescriptor.unparse(f.getType());
256 C.vload(0).vgetfield(valueClass(), f.getName(), desc);
257 if (f.getType().isPrimitive()) {
258 C.invokestatic(Wrapper.asWrapperType(f.getType()), "hashCode", "(" + desc + ")I", false);
259 } else {
260 C.invokestatic(Objects.class, "hashCode", "(Ljava/lang/Object;)I", false);
261 }
262 C.load("res").const_(31).imul();
263 C.iadd().store("res");
264 }
265 C.load("res").ireturn();
266 });
267 handleMap.put(key, result);
268 }
269 return result;
270 }
271
272 // ()__Value
273 public MethodHandle findConstructor(Lookup lookup, MethodType type) throws NoSuchMethodException, IllegalAccessException {
274 return MethodHandles.filterReturnValue(lookup.findConstructor(boxClass(), type), unbox());
275 }
276
277 // (__Value, T)__Value
278 public MethodHandle findWither(Lookup lookup, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
279 ValueHandleKey key = ValueHandleKind.WITHER.key(List.of(name, type));
280 MethodHandle result = handleMap.get(key);
281 if (result == null) {
282 String fieldType = BytecodeDescriptor.unparse(type);
283
284 result = MethodHandleBuilder.loadCode(valueLookup, mhName("wither$" + name), MethodType.methodType(valueClass(), valueClass(), type),
285 C -> C.vload(0).load(1).vwithfield(valueClass(), name, fieldType).vreturn());
286 handleMap.put(key, result);
287 }
288
289 // Allow access if the lookup class is the VCC or DVT and the lookup
290 // has private access
291 Class<?> lc = lookup.lookupClass();
292 if (lookup.hasPrivateAccess() && (valueClass() == lc || boxClass() == lc)) {
293 return result;
294 }
295 throw new IllegalAccessException(String.format("Class %s does not have vwithfield access to field %s.%s",
296 lc.getName(), boxClass().getName(), name));
297 }
298
299 public MethodHandle unbox() {
300 ValueHandleKey key = ValueHandleKind.UNBOX.key();
301 MethodHandle result = handleMap.get(key);
302 if (result == null) {
303 result = MethodHandleBuilder.loadCode(boxLookup, mhName("unbox"), MethodType.methodType(valueClass(), boxClass()),
304 C -> {
305 C.load(0).vunbox(valueClass()).vreturn();
306 });
307 handleMap.put(key, result);
308 }
309 return result;
310 }
311
312 public MethodHandle box() {
313 ValueHandleKey key = ValueHandleKind.BOX.key();
314 MethodHandle result = handleMap.get(key);
315 if (result == null) {
316 result = MethodHandleBuilder.loadCode(boxLookup, mhName("box"), MethodType.methodType(boxClass(), valueClass()),
317 C -> {
318 C.vload(0).vbox(boxClass()).areturn();
319 });
320 handleMap.put(key, result);
321 }
322 return result;
323 }
324
325 public MethodHandle newArray() {
326 Class<?> arrayValueClass = arrayValueClass();
327 ValueHandleKey key = ValueHandleKind.NEWARRAY.key();
328 MethodHandle result = handleMap.get(key);
329 if (result == null) {
330 result = MethodHandleBuilder.loadCode(boxLookup, mhName("newArray"), MethodType.methodType(arrayValueClass, int.class),
331 C -> {
332 C.load(0).anewarray(valueClass()).areturn();
333 });
334 handleMap.put(key, result);
335 }
336 return result;
337 }
338
339 public MethodHandle arrayGetter() {
340 Class<?> arrayValueClass = arrayValueClass();
341 ValueHandleKey key = ValueHandleKind.VALOAD.key();
342 MethodHandle result = handleMap.get(key);
343 if (result == null) {
344 result = MethodHandleBuilder.loadCode(boxLookup, mhName("arrayGet"), MethodType.methodType(valueClass(), arrayValueClass, int.class),
345 C -> {
346 C.load(0).load(1).vaload().vreturn();
347 });
348 handleMap.put(key, result);
349 }
350 return result;
351 }
352
353 public MethodHandle arraySetter() {
354 Class<?> arrayValueClass = arrayValueClass();
355 ValueHandleKey key = ValueHandleKind.VASTORE.key();
356 MethodHandle result = handleMap.get(key);
357 if (result == null) {
358 result = MethodHandleBuilder.loadCode(boxLookup, mhName("arraySet"), MethodType.methodType(void.class, arrayValueClass, int.class, valueClass()),
359 C -> {
360 C.load(0).load(1).load(2).vastore().return_();
361 });
362 handleMap.put(key, result);
363 }
364 return result;
365 }
366
367 public MethodHandle newMultiArray(int dims) {
368 Class<?> arrayValueClass = arrayValueClass(dims);
369 ValueHandleKey key = ValueHandleKind.MULTINEWARRAY.key(dims);
370 MethodHandle result = handleMap.get(key);
371 Class<?>[] params = new Class<?>[dims];
372 Arrays.fill(params, int.class);
373 if (result == null) {
374 result = MethodHandleBuilder.loadCode(boxLookup, mhName("newMultiArray"), MethodType.methodType(arrayValueClass, params),
375 C -> {
376 for (int i = 0 ; i < dims ; i++) {
377 C.load(i);
378 }
379 C.multianewarray(arrayValueClass, (byte)dims).areturn();
380 });
381 handleMap.put(key, result);
382 }
383 return result;
384 }
385
386 public MethodHandle identity() {
387 ValueHandleKey key = ValueHandleKind.IDENTITY.key();
388 MethodHandle result = handleMap.get(key);
389 if (result == null) {
390 result = MethodHandleBuilder.loadCode(boxLookup, mhName("identity"), MethodType.methodType(valueClass(), valueClass()),
391 C -> C.vload(0).vreturn());
392 handleMap.put(key, result);
393 }
394 return result;
395 }
396
397 public MethodHandle findGetter(Lookup lookup, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
398 ValueHandleKey key = ValueHandleKind.GETTER.key(List.of(name, type));
399 MethodHandle result = handleMap.get(key);
400 if (result == null) {
401 String fieldType = BytecodeDescriptor.unparse(type);
402 result = MethodHandleBuilder.loadCode(boxLookup, mhName("getter$" + name), MethodType.methodType(type, valueClass()),
403 C -> C.vload(0).vgetfield(valueClass(), name, fieldType).return_(fieldType));
404 handleMap.put(key, result);
405 }
406 //force access-check
407 lookup.findGetter(boxClass(), name, type);
408 return result;
409 }
410
411 private Field[] valueFields() {
412 int valFieldMask = Modifier.FINAL;
413 return Stream.of(sourceClass().getDeclaredFields())
414 .filter(f -> (f.getModifiers() & (valFieldMask | Modifier.STATIC)) == valFieldMask)
415 .toArray(Field[]::new);
416 }
417
418 }