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 String dimsStr = "[[[[[[[[[[[[[[[[";
187 if (dims < 1 || dims > 16) {
188 throw new IllegalArgumentException("cannot create array class for dimension > 16");
189 }
190 String cn = dimsStr.substring(0, dims) + "Q" + valueClass().getName() + ";";
191 return MinimalValueTypes_1_0.loadValueTypeClass(boxLookup.lookupClass(), cn);
192 }
193
194 public String toString() {
195 return "ValueType boxClass=" + boxClass() + " valueClass=" + valueClass();
196 }
197
198 String mhName(String opName) {
199 return sourceClass().getName() + "_" + opName;
200 }
201
202 public MethodHandle defaultValueConstant() {
203 ValueHandleKey key = ValueHandleKind.DEFAULT.key();
204 MethodHandle result = handleMap.get(key);
205 if (result == null) {
206 result = MethodHandleBuilder.loadCode(boxLookup, mhName("default"), MethodType.methodType(valueClass()),
207 C -> {
208 C.vdefault(valueClass()).vreturn();
209 });
210 handleMap.put(key, result);
211 }
212 return result;
213 }
214
215 public MethodHandle substitutabilityTest() {
216 ValueHandleKey key = ValueHandleKind.EQ.key();
217 MethodHandle result = handleMap.get(key);
218 if (result == null) {
219 result = MethodHandleBuilder.loadCode(valueLookup, mhName("subTest"), MethodType.methodType(boolean.class, valueClass(), valueClass()),
220 C -> {
221 for (Field f : valueFields()) {
222 String fDesc = BytecodeDescriptor.unparse(f.getType());
223 C.vload(0).vgetfield(valueClass(), f.getName(), fDesc);
224 C.vload(1).vgetfield(valueClass(), f.getName(), fDesc);
225 if (f.getType().isPrimitive()) {
226 C.ifcmp(fDesc, CondKind.NE, "fail");
227 } else {
228 C.invokestatic(Objects.class, "equals", "(Ljava/lang/Object;Ljava/lang/Object;)Z", false);
229 C.const_(0).ifcmp(TypeTag.I, CondKind.EQ, "fail");
230 }
231 }
232 C.const_(1);
233 C.ireturn();
234 C.label("fail");
235 C.const_(0);
236 C.ireturn();
237 });
238 handleMap.put(key, result);
239 }
240 return result;
241 }
242
243 public MethodHandle substitutabilityHashCode() {
244 ValueHandleKey key = ValueHandleKind.HASH.key();
245 MethodHandle result = handleMap.get(key);
246 if (result == null) {
247 result = MethodHandleBuilder.loadCode(valueLookup, mhName("subHash"), MethodType.methodType(int.class, valueClass()),
248 C -> {
249 C.withLocal("res", "I");
250 C.const_(1).store("res");
251 for (Field f : valueFields()) {
252 String desc = BytecodeDescriptor.unparse(f.getType());
253 C.vload(0).vgetfield(valueClass(), f.getName(), desc);
254 if (f.getType().isPrimitive()) {
255 C.invokestatic(Wrapper.asWrapperType(f.getType()), "hashCode", "(" + desc + ")I", false);
256 } else {
257 C.invokestatic(Objects.class, "hashCode", "(Ljava/lang/Object;)I", false);
258 }
259 C.load("res").const_(31).imul();
260 C.iadd().store("res");
261 }
262 C.load("res").ireturn();
263 });
264 handleMap.put(key, result);
265 }
266 return result;
267 }
268
269 //Todo: when 'vwithfield' is ready, this handle could be greatly simplified
270 public MethodHandle findWither(Lookup lookup, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
271 ValueHandleKey key = ValueHandleKind.WITHER.key(List.of(name, type));
272 MethodHandle result = handleMap.get(key);
273 if (result == null) {
274 MethodHandle mh = boxLookup.findGetter(boxClass(), name, type);
275 Field field = MethodHandles.reflectAs(Field.class, mh);
276 Class<?> erasedType = type.isPrimitive() ?
277 type : Object.class;
278 Method unsafeMethod = Stream.of(UNSAFE.getClass().getDeclaredMethods())
279 .filter(m -> m.getName().startsWith("put") &&
280 Arrays.asList(m.getParameterTypes()).equals(Arrays.asList(Object.class, long.class, erasedType)))
281 .findFirst().get();
282 long fieldOffset = UNSAFE.objectFieldOffset(field);
283 result = MethodHandleBuilder.loadCode(boxLookup, mhName("wither$" + name), MethodType.methodType(valueClass(), MethodHandle.class, valueClass(), type),
284 C -> {
285 C.withLocal("boxedVal", BytecodeDescriptor.unparse(boxClass()))
286 .load(1)
287 .vbox(boxClass())
288 .store("boxedVal")
289 .load(0)
290 .load("boxedVal")
291 .const_(fieldOffset)
292 .load(2);
293 MethodType unsafeMT = MethodType.methodType(unsafeMethod.getReturnType(), unsafeMethod.getParameterTypes());
294 C.invokevirtual(MethodHandle.class, "invokeExact", BytecodeDescriptor.unparse(unsafeMT), false)
295 .load("boxedVal")
296 .vunbox(valueClass())
297 .vreturn();
298 }).bindTo(MethodHandles.lookup().unreflect(unsafeMethod).bindTo(UNSAFE));
299 handleMap.put(key, result);
300 }
301 //force access-check
302 lookup.findGetter(boxClass(), name, type);
303 return result;
304 }
305
306 public MethodHandle unbox() {
307 ValueHandleKey key = ValueHandleKind.UNBOX.key();
308 MethodHandle result = handleMap.get(key);
309 if (result == null) {
310 result = MethodHandleBuilder.loadCode(boxLookup, mhName("unbox"), MethodType.methodType(valueClass(), boxClass()),
311 C -> {
312 C.load(0).vunbox(valueClass()).vreturn();
313 });
314 handleMap.put(key, result);
315 }
316 return result;
317 }
318
319 public MethodHandle box() {
320 ValueHandleKey key = ValueHandleKind.BOX.key();
321 MethodHandle result = handleMap.get(key);
322 if (result == null) {
323 result = MethodHandleBuilder.loadCode(boxLookup, mhName("box"), MethodType.methodType(boxClass(), valueClass()),
324 C -> {
325 C.vload(0).vbox(boxClass()).areturn();
326 });
327 handleMap.put(key, result);
328 }
329 return result;
330 }
331
332 public MethodHandle newArray() {
333 Class<?> arrayValueClass = arrayValueClass();
334 ValueHandleKey key = ValueHandleKind.NEWARRAY.key();
335 MethodHandle result = handleMap.get(key);
336 if (result == null) {
337 result = MethodHandleBuilder.loadCode(boxLookup, mhName("newArray"), MethodType.methodType(arrayValueClass, int.class),
338 C -> {
339 C.load(0).anewarray(valueClass()).areturn();
340 });
341 handleMap.put(key, result);
342 }
343 return result;
344 }
345
346 public MethodHandle arrayGetter() {
347 Class<?> arrayValueClass = arrayValueClass();
348 ValueHandleKey key = ValueHandleKind.VALOAD.key();
349 MethodHandle result = handleMap.get(key);
350 if (result == null) {
351 result = MethodHandleBuilder.loadCode(boxLookup, mhName("arrayGet"), MethodType.methodType(valueClass(), arrayValueClass, int.class),
352 C -> {
353 C.load(0).load(1).vaload().vreturn();
354 });
355 handleMap.put(key, result);
356 }
357 return result;
358 }
359
360 public MethodHandle arraySetter() {
361 Class<?> arrayValueClass = arrayValueClass();
362 ValueHandleKey key = ValueHandleKind.VASTORE.key();
363 MethodHandle result = handleMap.get(key);
364 if (result == null) {
365 result = MethodHandleBuilder.loadCode(boxLookup, mhName("arraySet"), MethodType.methodType(void.class, arrayValueClass, int.class, valueClass()),
366 C -> {
367 C.load(0).load(1).load(2).vastore().return_();
368 });
369 handleMap.put(key, result);
370 }
371 return result;
372 }
373
374 public MethodHandle newMultiArray(int dims) {
375 Class<?> arrayValueClass = arrayValueClass(dims);
376 ValueHandleKey key = ValueHandleKind.MULTINEWARRAY.key(dims);
377 MethodHandle result = handleMap.get(key);
378 Class<?>[] params = new Class<?>[dims];
379 Arrays.fill(params, int.class);
380 if (result == null) {
381 result = MethodHandleBuilder.loadCode(boxLookup, mhName("newMultiArray"), MethodType.methodType(arrayValueClass, params),
382 C -> {
383 for (int i = 0 ; i < dims ; i++) {
384 C.load(i);
385 }
386 C.multianewarray(arrayValueClass, (byte)dims).areturn();
387 });
388 handleMap.put(key, result);
389 }
390 return result;
391 }
392
393 public MethodHandle identity() {
394 ValueHandleKey key = ValueHandleKind.IDENTITY.key();
395 MethodHandle result = handleMap.get(key);
396 if (result == null) {
397 result = MethodHandleBuilder.loadCode(boxLookup, mhName("identity"), MethodType.methodType(valueClass(), valueClass()),
398 C -> C.vload(0).vreturn());
399 handleMap.put(key, result);
400 }
401 return result;
402 }
403
404 public MethodHandle findGetter(Lookup lookup, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
405 ValueHandleKey key = ValueHandleKind.GETTER.key(List.of(name, type));
406 MethodHandle result = handleMap.get(key);
407 if (result == null) {
408 String fieldType = BytecodeDescriptor.unparse(type);
409 result = MethodHandleBuilder.loadCode(boxLookup, mhName("getter$" + name), MethodType.methodType(type, valueClass()),
410 C -> C.vload(0).vgetfield(valueClass(), name, fieldType).return_(fieldType));
411 handleMap.put(key, result);
412 }
413 //force access-check
414 lookup.findGetter(boxClass(), name, type);
415 return result;
416 }
417
418 private Field[] valueFields() {
419 int valFieldMask = Modifier.FINAL;
420 return Stream.of(sourceClass().getDeclaredFields())
421 .filter(f -> (f.getModifiers() & (valFieldMask | Modifier.STATIC)) == valFieldMask)
422 .toArray(Field[]::new);
423 }
424
425 }