1 /* 2 * Copyright (c) 2011, 2017, 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. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 package jdk.vm.ci.hotspot; 24 25 import static java.util.Objects.requireNonNull; 26 import static jdk.vm.ci.hotspot.CompilerToVM.compilerToVM; 27 import static jdk.vm.ci.hotspot.HotSpotConstantPool.isSignaturePolymorphicHolder; 28 import static jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.runtime; 29 import static jdk.vm.ci.hotspot.HotSpotModifiers.jvmClassModifiers; 30 import static jdk.vm.ci.hotspot.HotSpotVMConfig.config; 31 import static jdk.vm.ci.hotspot.UnsafeAccess.UNSAFE; 32 33 import java.lang.annotation.Annotation; 34 import java.lang.reflect.Array; 35 import java.lang.reflect.Constructor; 36 import java.lang.reflect.Method; 37 import java.lang.reflect.Modifier; 38 import java.nio.ByteOrder; 39 import java.util.HashMap; 40 41 import jdk.vm.ci.common.JVMCIError; 42 import jdk.vm.ci.meta.Assumptions.AssumptionResult; 43 import jdk.vm.ci.meta.Assumptions.ConcreteMethod; 44 import jdk.vm.ci.meta.Assumptions.ConcreteSubtype; 45 import jdk.vm.ci.meta.Assumptions.LeafType; 46 import jdk.vm.ci.meta.Assumptions.NoFinalizableSubclass; 47 import jdk.vm.ci.meta.Constant; 48 import jdk.vm.ci.meta.JavaConstant; 49 import jdk.vm.ci.meta.JavaKind; 50 import jdk.vm.ci.meta.JavaType; 51 import jdk.vm.ci.meta.ResolvedJavaField; 52 import jdk.vm.ci.meta.ResolvedJavaMethod; 53 import jdk.vm.ci.meta.ResolvedJavaType; 54 55 /** 56 * Implementation of {@link JavaType} for resolved non-primitive HotSpot classes. 57 */ 58 final class HotSpotResolvedObjectTypeImpl extends HotSpotResolvedJavaType implements HotSpotResolvedObjectType, MetaspaceWrapperObject { 59 60 private static final HotSpotResolvedJavaField[] NO_FIELDS = new HotSpotResolvedJavaField[0]; 61 private static final int METHOD_CACHE_ARRAY_CAPACITY = 8; 62 63 /** 64 * The Java class this type represents. 65 */ 66 private final Class<?> javaClass; 67 private HotSpotResolvedJavaMethodImpl[] methodCacheArray; 68 private HashMap<Long, HotSpotResolvedJavaMethodImpl> methodCacheHashMap; 69 private HotSpotResolvedJavaField[] instanceFields; 70 private HotSpotResolvedObjectTypeImpl[] interfaces; 71 private HotSpotConstantPool constantPool; 72 final HotSpotJVMCIMetaAccessContext context; 73 private HotSpotResolvedObjectType arrayOfType; 74 75 /** 76 * Gets the JVMCI mirror for a {@link Class} object. 77 * 78 * @return the {@link HotSpotResolvedJavaType} corresponding to {@code javaClass} 79 */ 80 static HotSpotResolvedObjectTypeImpl fromObjectClass(Class<?> javaClass) { 81 return (HotSpotResolvedObjectTypeImpl) runtime().fromClass(javaClass); 82 } 83 84 /** 85 * Gets the JVMCI mirror from a HotSpot type. Since {@link Class} is already a proxy for the 86 * underlying Klass*, it is used instead of the raw Klass*. 87 * 88 * Called from the VM. 89 * 90 * @param javaClass a {@link Class} object 91 * @return the {@link ResolvedJavaType} corresponding to {@code javaClass} 92 */ 93 @SuppressWarnings("unused") 94 private static HotSpotResolvedObjectTypeImpl fromMetaspace(Class<?> javaClass) { 95 return fromObjectClass(javaClass); 96 } 97 98 /** 99 * Creates the JVMCI mirror for a {@link Class} object. 100 * 101 * <p> 102 * <b>NOTE</b>: Creating an instance of this class does not install the mirror for the 103 * {@link Class} type. Use {@link #fromObjectClass(Class)} or {@link #fromMetaspace(Class)} 104 * instead. 105 * </p> 106 * 107 * @param javaClass the Class to create the mirror for 108 * @param context 109 */ 110 HotSpotResolvedObjectTypeImpl(Class<?> javaClass, HotSpotJVMCIMetaAccessContext context) { 111 super(getSignatureName(javaClass)); 112 this.javaClass = javaClass; 113 this.context = context; 114 assert getName().charAt(0) != '[' || isArray() : getName(); 115 } 116 117 /** 118 * Returns the name of this type as it would appear in a signature. 119 */ 120 private static String getSignatureName(Class<?> javaClass) { 121 if (javaClass.isArray()) { 122 return javaClass.getName().replace('.', '/'); 123 } 124 return "L" + javaClass.getName().replace('.', '/') + ";"; 125 } 126 127 /** 128 * Gets the metaspace Klass for this type. 129 */ 130 long getMetaspaceKlass() { 131 if (HotSpotJVMCIRuntime.getHostWordKind() == JavaKind.Long) { 132 return UNSAFE.getLong(javaClass, config().klassOffset); 133 } 134 return UNSAFE.getInt(javaClass, config().klassOffset) & 0xFFFFFFFFL; 135 } 136 137 @Override 138 public long getMetaspacePointer() { 139 return getMetaspaceKlass(); 140 } 141 142 /** 143 * The Klass* for this object is kept alive by the direct reference to {@link #javaClass} so no 144 * extra work is required. 145 */ 146 @Override 147 public boolean isRegistered() { 148 return true; 149 } 150 151 @Override 152 public int getModifiers() { 153 if (isArray()) { 154 return (getElementalType().getModifiers() & (Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED)) | Modifier.FINAL | Modifier.ABSTRACT; 155 } else { 156 return getAccessFlags() & jvmClassModifiers(); 157 } 158 } 159 160 public int getAccessFlags() { 161 HotSpotVMConfig config = config(); 162 return UNSAFE.getInt(getMetaspaceKlass() + config.klassAccessFlagsOffset); 163 } 164 165 @Override 166 public HotSpotResolvedObjectType getArrayClass() { 167 if (arrayOfType == null) { 168 arrayOfType = fromObjectClass(Array.newInstance(mirror(), 0).getClass()); 169 } 170 return arrayOfType; 171 } 172 173 @Override 174 public ResolvedJavaType getComponentType() { 175 Class<?> javaComponentType = mirror().getComponentType(); 176 return javaComponentType == null ? null : runtime().fromClass(javaComponentType); 177 } 178 179 @Override 180 public AssumptionResult<ResolvedJavaType> findLeafConcreteSubtype() { 181 if (isLeaf()) { 182 // No assumptions are required. 183 return new AssumptionResult<>(this); 184 } 185 HotSpotVMConfig config = config(); 186 if (isArray()) { 187 ResolvedJavaType elementalType = getElementalType(); 188 AssumptionResult<ResolvedJavaType> elementType = elementalType.findLeafConcreteSubtype(); 189 if (elementType != null && elementType.getResult().equals(elementalType)) { 190 /* 191 * If the elementType is leaf then the array is leaf under the same assumptions but 192 * only if the element type is exactly the leaf type. The element type can be 193 * abstract even if there is only one implementor of the abstract type. 194 */ 195 AssumptionResult<ResolvedJavaType> result = new AssumptionResult<>(this); 196 result.add(elementType); 197 return result; 198 } 199 return null; 200 } else if (isInterface()) { 201 HotSpotResolvedObjectTypeImpl implementor = getSingleImplementor(); 202 /* 203 * If the implementor field contains itself that indicates that the interface has more 204 * than one implementors (see: InstanceKlass::add_implementor). 205 */ 206 if (implementor == null || implementor.equals(this)) { 207 return null; 208 } 209 210 assert !implementor.isInterface(); 211 if (implementor.isAbstract() || !implementor.isLeafClass()) { 212 AssumptionResult<ResolvedJavaType> leafConcreteSubtype = implementor.findLeafConcreteSubtype(); 213 if (leafConcreteSubtype != null) { 214 assert !leafConcreteSubtype.getResult().equals(implementor); 215 AssumptionResult<ResolvedJavaType> newResult = new AssumptionResult<>(leafConcreteSubtype.getResult(), new ConcreteSubtype(this, implementor)); 216 // Accumulate leaf assumptions and return the combined result. 217 newResult.add(leafConcreteSubtype); 218 return newResult; 219 } 220 return null; 221 } 222 return concreteSubtype(implementor); 223 } else { 224 HotSpotResolvedObjectTypeImpl type = this; 225 while (type.isAbstract()) { 226 HotSpotResolvedObjectTypeImpl subklass = type.getSubklass(); 227 if (subklass == null || UNSAFE.getAddress(subklass.getMetaspaceKlass() + config.nextSiblingOffset) != 0) { 228 return null; 229 } 230 type = subklass; 231 } 232 if (type.isAbstract() || type.isInterface() || !type.isLeafClass()) { 233 return null; 234 } 235 if (this.isAbstract()) { 236 return concreteSubtype(type); 237 } else { 238 assert this.equals(type); 239 return new AssumptionResult<>(type, new LeafType(type)); 240 } 241 } 242 } 243 244 private AssumptionResult<ResolvedJavaType> concreteSubtype(HotSpotResolvedObjectTypeImpl type) { 245 if (type.isLeaf()) { 246 return new AssumptionResult<>(type, new ConcreteSubtype(this, type)); 247 } else { 248 return new AssumptionResult<>(type, new LeafType(type), new ConcreteSubtype(this, type)); 249 } 250 } 251 252 /** 253 * Returns if type {@code type} is a leaf class. This is the case if the 254 * {@code Klass::_subklass} field of the underlying class is zero. 255 * 256 * @return true if the type is a leaf class 257 */ 258 private boolean isLeafClass() { 259 return UNSAFE.getLong(this.getMetaspaceKlass() + config().subklassOffset) == 0; 260 } 261 262 /** 263 * Returns the {@code Klass::_subklass} field of the underlying metaspace klass for the given 264 * type {@code type}. 265 * 266 * @return value of the subklass field as metaspace klass pointer 267 */ 268 private HotSpotResolvedObjectTypeImpl getSubklass() { 269 return compilerToVM().getResolvedJavaType(this, config().subklassOffset, false); 270 } 271 272 @Override 273 public HotSpotResolvedObjectTypeImpl getSuperclass() { 274 Class<?> javaSuperclass = mirror().getSuperclass(); 275 return javaSuperclass == null ? null : fromObjectClass(javaSuperclass); 276 } 277 278 @Override 279 public HotSpotResolvedObjectTypeImpl[] getInterfaces() { 280 if (interfaces == null) { 281 Class<?>[] javaInterfaces = mirror().getInterfaces(); 282 HotSpotResolvedObjectTypeImpl[] result = new HotSpotResolvedObjectTypeImpl[javaInterfaces.length]; 283 for (int i = 0; i < javaInterfaces.length; i++) { 284 result[i] = fromObjectClass(javaInterfaces[i]); 285 } 286 interfaces = result; 287 } 288 return interfaces; 289 } 290 291 @Override 292 public HotSpotResolvedObjectTypeImpl getSingleImplementor() { 293 if (!isInterface()) { 294 throw new JVMCIError("Cannot call getSingleImplementor() on a non-interface type: %s", this); 295 } 296 return compilerToVM().getImplementor(this); 297 } 298 299 public HotSpotResolvedObjectTypeImpl getSupertype() { 300 if (isArray()) { 301 ResolvedJavaType componentType = getComponentType(); 302 if (mirror() == Object[].class || componentType.isPrimitive()) { 303 return fromObjectClass(Object.class); 304 } 305 return (HotSpotResolvedObjectTypeImpl) ((HotSpotResolvedObjectTypeImpl) componentType).getSupertype().getArrayClass(); 306 } 307 if (isInterface()) { 308 return fromObjectClass(Object.class); 309 } 310 return getSuperclass(); 311 } 312 313 @Override 314 public HotSpotResolvedObjectType findLeastCommonAncestor(ResolvedJavaType otherType) { 315 if (otherType.isPrimitive()) { 316 return null; 317 } else { 318 HotSpotResolvedObjectTypeImpl t1 = this; 319 HotSpotResolvedObjectTypeImpl t2 = (HotSpotResolvedObjectTypeImpl) otherType; 320 while (true) { 321 if (t1.isAssignableFrom(t2)) { 322 return t1; 323 } 324 if (t2.isAssignableFrom(t1)) { 325 return t2; 326 } 327 t1 = t1.getSupertype(); 328 t2 = t2.getSupertype(); 329 } 330 } 331 } 332 333 @Override 334 public AssumptionResult<Boolean> hasFinalizableSubclass() { 335 assert !isArray(); 336 if (!compilerToVM().hasFinalizableSubclass(this)) { 337 return new AssumptionResult<>(false, new NoFinalizableSubclass(this)); 338 } 339 return new AssumptionResult<>(true); 340 } 341 342 @Override 343 public boolean hasFinalizer() { 344 return (getAccessFlags() & config().jvmAccHasFinalizer) != 0; 345 } 346 347 @Override 348 public boolean isPrimitive() { 349 return false; 350 } 351 352 @Override 353 public boolean isArray() { 354 return mirror().isArray(); 355 } 356 357 @Override 358 public boolean isInitialized() { 359 return isArray() ? true : getInitState() == config().instanceKlassStateFullyInitialized; 360 } 361 362 @Override 363 public boolean isLinked() { 364 return isArray() ? true : getInitState() >= config().instanceKlassStateLinked; 365 } 366 367 /** 368 * Returns the value of the state field {@code InstanceKlass::_init_state} of the metaspace 369 * klass. 370 * 371 * @return state field value of this type 372 */ 373 private int getInitState() { 374 assert !isArray() : "_init_state only exists in InstanceKlass"; 375 return UNSAFE.getByte(getMetaspaceKlass() + config().instanceKlassInitStateOffset) & 0xFF; 376 } 377 378 @Override 379 public void initialize() { 380 if (!isInitialized()) { 381 UNSAFE.ensureClassInitialized(mirror()); 382 assert isInitialized(); 383 } 384 } 385 386 @Override 387 public boolean isInstance(JavaConstant obj) { 388 if (obj.getJavaKind() == JavaKind.Object && !obj.isNull()) { 389 return mirror().isInstance(((HotSpotObjectConstantImpl) obj).object()); 390 } 391 return false; 392 } 393 394 @Override 395 public boolean isInstanceClass() { 396 return !isArray() && !isInterface(); 397 } 398 399 @Override 400 public boolean isInterface() { 401 return mirror().isInterface(); 402 } 403 404 @Override 405 public boolean isAssignableFrom(ResolvedJavaType other) { 406 assert other != null; 407 if (other instanceof HotSpotResolvedObjectTypeImpl) { 408 HotSpotResolvedObjectTypeImpl otherType = (HotSpotResolvedObjectTypeImpl) other; 409 return mirror().isAssignableFrom(otherType.mirror()); 410 } 411 return false; 412 } 413 414 @Override 415 public boolean isJavaLangObject() { 416 return javaClass.equals(Object.class); 417 } 418 419 @Override 420 public JavaKind getJavaKind() { 421 return JavaKind.Object; 422 } 423 424 @Override 425 public ResolvedJavaMethod resolveMethod(ResolvedJavaMethod method, ResolvedJavaType callerType) { 426 assert !callerType.isArray(); 427 if (isInterface()) { 428 // Methods can only be resolved against concrete types 429 return null; 430 } 431 if (method.isConcrete() && method.getDeclaringClass().equals(this) && method.isPublic() && !isSignaturePolymorphicHolder(method.getDeclaringClass())) { 432 return method; 433 } 434 if (!method.getDeclaringClass().isAssignableFrom(this)) { 435 return null; 436 } 437 HotSpotResolvedJavaMethodImpl hotSpotMethod = (HotSpotResolvedJavaMethodImpl) method; 438 HotSpotResolvedObjectTypeImpl hotSpotCallerType = (HotSpotResolvedObjectTypeImpl) callerType; 439 return compilerToVM().resolveMethod(this, hotSpotMethod, hotSpotCallerType); 440 } 441 442 public HotSpotConstantPool getConstantPool() { 443 if (constantPool == null || !isArray() && UNSAFE.getAddress(getMetaspaceKlass() + config().instanceKlassConstantsOffset) != constantPool.getMetaspaceConstantPool()) { 444 /* 445 * If the pointer to the ConstantPool has changed since this was last read refresh the 446 * HotSpotConstantPool wrapper object. This ensures that uses of the constant pool are 447 * operating on the latest one and that HotSpotResolvedJavaMethodImpls will be able to 448 * use the shared copy instead of creating their own instance. 449 */ 450 constantPool = compilerToVM().getConstantPool(this); 451 } 452 return constantPool; 453 } 454 455 /** 456 * Gets the instance size of this type. If an instance of this type cannot be fast path 457 * allocated, then the returned value is negative (its absolute value gives the size). Must not 458 * be called if this is an array or interface type. 459 */ 460 public int instanceSize() { 461 assert !isArray(); 462 assert !isInterface(); 463 464 HotSpotVMConfig config = config(); 465 final int layoutHelper = layoutHelper(); 466 assert layoutHelper > config.klassLayoutHelperNeutralValue : "must be instance"; 467 468 // See: Klass::layout_helper_size_in_bytes 469 int size = layoutHelper & ~config.klassLayoutHelperInstanceSlowPathBit; 470 471 // See: Klass::layout_helper_needs_slow_path 472 boolean needsSlowPath = (layoutHelper & config.klassLayoutHelperInstanceSlowPathBit) != 0; 473 474 return needsSlowPath ? -size : size; 475 } 476 477 public int layoutHelper() { 478 HotSpotVMConfig config = config(); 479 return UNSAFE.getInt(getMetaspaceKlass() + config.klassLayoutHelperOffset); 480 } 481 482 @Override 483 public long getFingerprint() { 484 return compilerToVM().getFingerprint(getMetaspaceKlass()); 485 } 486 487 synchronized HotSpotResolvedJavaMethod createMethod(long metaspaceMethod) { 488 // Maintain cache as array. 489 if (methodCacheArray == null) { 490 methodCacheArray = new HotSpotResolvedJavaMethodImpl[METHOD_CACHE_ARRAY_CAPACITY]; 491 } 492 493 int i = 0; 494 for (; i < methodCacheArray.length; ++i) { 495 HotSpotResolvedJavaMethodImpl curMethod = methodCacheArray[i]; 496 if (curMethod == null) { 497 HotSpotResolvedJavaMethodImpl newMethod = new HotSpotResolvedJavaMethodImpl(this, metaspaceMethod); 498 methodCacheArray[i] = newMethod; 499 context.add(newMethod); 500 return newMethod; 501 } else if (curMethod.getMetaspacePointer() == metaspaceMethod) { 502 return curMethod; 503 } 504 } 505 506 // Fall-back to hash table. 507 if (methodCacheHashMap == null) { 508 methodCacheHashMap = new HashMap<>(); 509 } 510 511 HotSpotResolvedJavaMethodImpl lookupResult = methodCacheHashMap.get(metaspaceMethod); 512 if (lookupResult == null) { 513 HotSpotResolvedJavaMethodImpl newMethod = new HotSpotResolvedJavaMethodImpl(this, metaspaceMethod); 514 methodCacheHashMap.put(metaspaceMethod, newMethod); 515 context.add(lookupResult); 516 return newMethod; 517 } else { 518 return lookupResult; 519 } 520 } 521 522 public int getVtableLength() { 523 HotSpotVMConfig config = config(); 524 if (isInterface() || isArray()) { 525 /* Everything has the core vtable of java.lang.Object */ 526 return config.baseVtableLength(); 527 } 528 int result = UNSAFE.getInt(getMetaspaceKlass() + config.klassVtableLengthOffset) / (config.vtableEntrySize / config.heapWordSize); 529 assert result >= config.baseVtableLength() : UNSAFE.getInt(getMetaspaceKlass() + config.klassVtableLengthOffset) + " " + config.vtableEntrySize; 530 return result; 531 } 532 533 synchronized HotSpotResolvedJavaField createField(JavaType type, long offset, int rawFlags, int index) { 534 return new HotSpotResolvedJavaFieldImpl(this, type, offset, rawFlags, index); 535 } 536 537 @Override 538 public AssumptionResult<ResolvedJavaMethod> findUniqueConcreteMethod(ResolvedJavaMethod method) { 539 HotSpotResolvedJavaMethod hmethod = (HotSpotResolvedJavaMethod) method; 540 HotSpotResolvedObjectType declaredHolder = hmethod.getDeclaringClass(); 541 /* 542 * Sometimes the receiver type in the graph hasn't stabilized to a subtype of declared 543 * holder, usually because of phis, so make sure that the type is related to the declared 544 * type before using it for lookup. Unlinked types should also be ignored because we can't 545 * resolve the proper method to invoke. Generally unlinked types in invokes should result in 546 * a deopt instead since they can't really be used if they aren't linked yet. 547 */ 548 if (!declaredHolder.isAssignableFrom(this) || this.isArray() || this.equals(declaredHolder) || !isLinked() || isInterface()) { 549 ResolvedJavaMethod result = hmethod.uniqueConcreteMethod(declaredHolder); 550 if (result != null) { 551 return new AssumptionResult<>(result, new ConcreteMethod(method, declaredHolder, result)); 552 } 553 return null; 554 } 555 /* 556 * The holder may be a subtype of the declaredHolder so make sure to resolve the method to 557 * the correct method for the subtype. 558 */ 559 HotSpotResolvedJavaMethod resolvedMethod = (HotSpotResolvedJavaMethod) resolveMethod(hmethod, this); 560 if (resolvedMethod == null) { 561 // The type isn't known to implement the method. 562 return null; 563 } 564 565 ResolvedJavaMethod result = resolvedMethod.uniqueConcreteMethod(this); 566 if (result != null) { 567 return new AssumptionResult<>(result, new ConcreteMethod(method, this, result)); 568 } 569 return null; 570 } 571 572 FieldInfo createFieldInfo(int index) { 573 return new FieldInfo(index); 574 } 575 576 /** 577 * This class represents the field information for one field contained in the fields array of an 578 * {@code InstanceKlass}. The implementation is similar to the native {@code FieldInfo} class. 579 */ 580 class FieldInfo { 581 /** 582 * Native pointer into the array of Java shorts. 583 */ 584 private final long metaspaceData; 585 586 /** 587 * Creates a field info for the field in the fields array at index {@code index}. 588 * 589 * @param index index to the fields array 590 */ 591 FieldInfo(int index) { 592 HotSpotVMConfig config = config(); 593 // Get Klass::_fields 594 final long metaspaceFields = UNSAFE.getAddress(getMetaspaceKlass() + config.instanceKlassFieldsOffset); 595 assert config.fieldInfoFieldSlots == 6 : "revisit the field parsing code"; 596 int offset = config.fieldInfoFieldSlots * Short.BYTES * index; 597 metaspaceData = metaspaceFields + config.arrayU2DataOffset + offset; 598 } 599 600 private int getAccessFlags() { 601 return readFieldSlot(config().fieldInfoAccessFlagsOffset); 602 } 603 604 private int getNameIndex() { 605 return readFieldSlot(config().fieldInfoNameIndexOffset); 606 } 607 608 private int getSignatureIndex() { 609 return readFieldSlot(config().fieldInfoSignatureIndexOffset); 610 } 611 612 public int getOffset() { 613 HotSpotVMConfig config = config(); 614 final int lowPacked = readFieldSlot(config.fieldInfoLowPackedOffset); 615 final int highPacked = readFieldSlot(config.fieldInfoHighPackedOffset); 616 final int offset = ((highPacked << Short.SIZE) | lowPacked) >> config.fieldInfoTagSize; 617 return offset; 618 } 619 620 /** 621 * Helper method to read an entry (slot) from the field array. Currently field info is laid 622 * on top an array of Java shorts. 623 */ 624 private int readFieldSlot(int index) { 625 int offset = Short.BYTES * index; 626 return UNSAFE.getChar(metaspaceData + offset); 627 } 628 629 /** 630 * Returns the name of this field as a {@link String}. If the field is an internal field the 631 * name index is pointing into the vmSymbols table. 632 */ 633 public String getName() { 634 final int nameIndex = getNameIndex(); 635 return isInternal() ? config().symbolAt(nameIndex) : getConstantPool().lookupUtf8(nameIndex); 636 } 637 638 /** 639 * Returns the signature of this field as {@link String}. If the field is an internal field 640 * the signature index is pointing into the vmSymbols table. 641 */ 642 public String getSignature() { 643 final int signatureIndex = getSignatureIndex(); 644 return isInternal() ? config().symbolAt(signatureIndex) : getConstantPool().lookupUtf8(signatureIndex); 645 } 646 647 public JavaType getType() { 648 String signature = getSignature(); 649 return runtime().lookupType(signature, HotSpotResolvedObjectTypeImpl.this, false); 650 } 651 652 private boolean isInternal() { 653 return (getAccessFlags() & config().jvmAccFieldInternal) != 0; 654 } 655 656 public boolean isStatic() { 657 return Modifier.isStatic(getAccessFlags()); 658 } 659 660 public boolean hasGenericSignature() { 661 return (getAccessFlags() & config().jvmAccFieldHasGenericSignature) != 0; 662 } 663 } 664 665 @Override 666 public ResolvedJavaField[] getInstanceFields(boolean includeSuperclasses) { 667 if (instanceFields == null) { 668 if (isArray() || isInterface()) { 669 instanceFields = NO_FIELDS; 670 } else { 671 HotSpotResolvedJavaField[] prepend = NO_FIELDS; 672 if (getSuperclass() != null) { 673 prepend = (HotSpotResolvedJavaField[]) getSuperclass().getInstanceFields(true); 674 } 675 instanceFields = getFields(false, prepend); 676 } 677 } 678 if (!includeSuperclasses && getSuperclass() != null) { 679 int superClassFieldCount = getSuperclass().getInstanceFields(true).length; 680 if (superClassFieldCount == instanceFields.length) { 681 // This class does not have any instance fields of its own. 682 return NO_FIELDS; 683 } else if (superClassFieldCount != 0) { 684 HotSpotResolvedJavaField[] result = new HotSpotResolvedJavaField[instanceFields.length - superClassFieldCount]; 685 System.arraycopy(instanceFields, superClassFieldCount, result, 0, result.length); 686 return result; 687 } else { 688 // The super classes of this class do not have any instance fields. 689 } 690 } 691 return instanceFields; 692 } 693 694 @Override 695 public ResolvedJavaField[] getStaticFields() { 696 if (isArray()) { 697 return new HotSpotResolvedJavaField[0]; 698 } else { 699 return getFields(true, NO_FIELDS); 700 } 701 } 702 703 /** 704 * Gets the instance or static fields of this class. 705 * 706 * @param retrieveStaticFields specifies whether to return instance or static fields 707 * @param prepend an array to be prepended to the returned result 708 */ 709 private HotSpotResolvedJavaField[] getFields(boolean retrieveStaticFields, HotSpotResolvedJavaField[] prepend) { 710 HotSpotVMConfig config = config(); 711 final long metaspaceFields = UNSAFE.getAddress(getMetaspaceKlass() + config.instanceKlassFieldsOffset); 712 int metaspaceFieldsLength = UNSAFE.getInt(metaspaceFields + config.arrayU1LengthOffset); 713 int resultCount = 0; 714 int index = 0; 715 for (int i = 0; i < metaspaceFieldsLength; i += config.fieldInfoFieldSlots, index++) { 716 FieldInfo field = new FieldInfo(index); 717 if (field.hasGenericSignature()) { 718 metaspaceFieldsLength--; 719 } 720 721 if (field.isStatic() == retrieveStaticFields) { 722 resultCount++; 723 } 724 } 725 726 if (resultCount == 0) { 727 return prepend; 728 } 729 730 int prependLength = prepend.length; 731 resultCount += prependLength; 732 733 HotSpotResolvedJavaField[] result = new HotSpotResolvedJavaField[resultCount]; 734 if (prependLength != 0) { 735 System.arraycopy(prepend, 0, result, 0, prependLength); 736 } 737 738 int resultIndex = prependLength; 739 for (int i = 0; i < index; ++i) { 740 FieldInfo field = new FieldInfo(i); 741 if (field.isStatic() == retrieveStaticFields) { 742 int offset = field.getOffset(); 743 HotSpotResolvedJavaField resolvedJavaField = createField(field.getType(), offset, field.getAccessFlags(), i); 744 745 // Make sure the result is sorted by offset. 746 int j; 747 for (j = resultIndex - 1; j >= prependLength && result[j].offset() > offset; j--) { 748 result[j + 1] = result[j]; 749 } 750 result[j + 1] = resolvedJavaField; 751 resultIndex++; 752 } 753 } 754 755 return result; 756 } 757 758 @Override 759 public Class<?> mirror() { 760 return javaClass; 761 } 762 763 @Override 764 public String getSourceFileName() { 765 HotSpotVMConfig config = config(); 766 final int sourceFileNameIndex = UNSAFE.getChar(getMetaspaceKlass() + config.instanceKlassSourceFileNameIndexOffset); 767 if (sourceFileNameIndex == 0) { 768 return null; 769 } 770 return getConstantPool().lookupUtf8(sourceFileNameIndex); 771 } 772 773 @Override 774 public Annotation[] getAnnotations() { 775 return mirror().getAnnotations(); 776 } 777 778 @Override 779 public Annotation[] getDeclaredAnnotations() { 780 return mirror().getDeclaredAnnotations(); 781 } 782 783 @Override 784 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) { 785 return mirror().getAnnotation(annotationClass); 786 } 787 788 /** 789 * Performs a fast-path check that this type is resolved in the context of a given accessing 790 * class. A negative result does not mean this type is not resolved with respect to 791 * {@code accessingClass}. That can only be determined by 792 * {@linkplain HotSpotJVMCIRuntime#lookupType(String, HotSpotResolvedObjectType, boolean) 793 * re-resolving} the type. 794 */ 795 public boolean isDefinitelyResolvedWithRespectTo(ResolvedJavaType accessingClass) { 796 assert accessingClass != null; 797 ResolvedJavaType elementType = getElementalType(); 798 if (elementType.isPrimitive()) { 799 // Primitive type resolution is context free. 800 return true; 801 } 802 if (elementType.getName().startsWith("Ljava/")) { 803 // Classes in a java.* package can only be defined by the 804 // boot class loader. This is enforced by ClassLoader.preDefineClass() 805 assert mirror().getClassLoader() == null; 806 return true; 807 } 808 ClassLoader thisCl = mirror().getClassLoader(); 809 ClassLoader accessingClassCl = ((HotSpotResolvedObjectTypeImpl) accessingClass).mirror().getClassLoader(); 810 return thisCl == accessingClassCl; 811 } 812 813 @Override 814 public ResolvedJavaType resolve(ResolvedJavaType accessingClass) { 815 if (isDefinitelyResolvedWithRespectTo(requireNonNull(accessingClass))) { 816 return this; 817 } 818 HotSpotResolvedObjectTypeImpl accessingType = (HotSpotResolvedObjectTypeImpl) accessingClass; 819 return (ResolvedJavaType) runtime().lookupType(getName(), accessingType, true); 820 } 821 822 /** 823 * Gets the metaspace Klass boxed in a {@link JavaConstant}. 824 */ 825 public Constant klass() { 826 return HotSpotMetaspaceConstantImpl.forMetaspaceObject(this, false); 827 } 828 829 public boolean isPrimaryType() { 830 return config().secondarySuperCacheOffset != superCheckOffset(); 831 } 832 833 public int superCheckOffset() { 834 HotSpotVMConfig config = config(); 835 return UNSAFE.getInt(getMetaspaceKlass() + config.superCheckOffsetOffset); 836 } 837 838 public long prototypeMarkWord() { 839 HotSpotVMConfig config = config(); 840 if (isArray()) { 841 return config.arrayPrototypeMarkWord(); 842 } else { 843 return UNSAFE.getAddress(getMetaspaceKlass() + config.prototypeMarkWordOffset); 844 } 845 } 846 847 @Override 848 public ResolvedJavaField findInstanceFieldWithOffset(long offset, JavaKind expectedEntryKind) { 849 ResolvedJavaField[] declaredFields = getInstanceFields(true); 850 for (ResolvedJavaField field : declaredFields) { 851 HotSpotResolvedJavaField resolvedField = (HotSpotResolvedJavaField) field; 852 long resolvedFieldOffset = resolvedField.offset(); 853 // @formatter:off 854 if (ByteOrder.nativeOrder() == ByteOrder.BIG_ENDIAN && 855 expectedEntryKind.isPrimitive() && 856 !expectedEntryKind.equals(JavaKind.Void) && 857 resolvedField.getJavaKind().isPrimitive()) { 858 resolvedFieldOffset += 859 resolvedField.getJavaKind().getByteCount() - 860 Math.min(resolvedField.getJavaKind().getByteCount(), 4 + expectedEntryKind.getByteCount()); 861 } 862 if (resolvedFieldOffset == offset) { 863 return field; 864 } 865 // @formatter:on 866 } 867 return null; 868 } 869 870 @Override 871 public boolean isLocal() { 872 return mirror().isLocalClass(); 873 } 874 875 @Override 876 public boolean isMember() { 877 return mirror().isMemberClass(); 878 } 879 880 @Override 881 public HotSpotResolvedObjectTypeImpl getEnclosingType() { 882 final Class<?> encl = mirror().getEnclosingClass(); 883 return encl == null ? null : fromObjectClass(encl); 884 } 885 886 @Override 887 public ResolvedJavaMethod[] getDeclaredConstructors() { 888 Constructor<?>[] constructors = mirror().getDeclaredConstructors(); 889 ResolvedJavaMethod[] result = new ResolvedJavaMethod[constructors.length]; 890 for (int i = 0; i < constructors.length; i++) { 891 result[i] = runtime().getHostJVMCIBackend().getMetaAccess().lookupJavaMethod(constructors[i]); 892 assert result[i].isConstructor(); 893 } 894 return result; 895 } 896 897 @Override 898 public ResolvedJavaMethod[] getDeclaredMethods() { 899 Method[] methods = mirror().getDeclaredMethods(); 900 ResolvedJavaMethod[] result = new ResolvedJavaMethod[methods.length]; 901 for (int i = 0; i < methods.length; i++) { 902 result[i] = runtime().getHostJVMCIBackend().getMetaAccess().lookupJavaMethod(methods[i]); 903 assert !result[i].isConstructor(); 904 } 905 return result; 906 } 907 908 public ResolvedJavaMethod getClassInitializer() { 909 return compilerToVM().getClassInitializer(this); 910 } 911 912 @Override 913 public String toString() { 914 return "HotSpotType<" + getName() + ", resolved>"; 915 } 916 917 @Override 918 public boolean isCloneableWithAllocation() { 919 return (getAccessFlags() & config().jvmAccIsCloneableFast) != 0; 920 } 921 }