1 /*
2 * Copyright (c) 1997, 2019, 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 */
24
25 #include "precompiled.hpp"
26 #include "classfile/moduleEntry.hpp"
27 #include "classfile/packageEntry.hpp"
28 #include "classfile/symbolTable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmSymbols.hpp"
31 #include "gc/shared/collectedHeap.inline.hpp"
32 #include "memory/iterator.inline.hpp"
33 #include "memory/metadataFactory.hpp"
34 #include "memory/metaspaceClosure.hpp"
35 #include "memory/oopFactory.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "memory/universe.hpp"
38 #include "oops/arrayKlass.inline.hpp"
39 #include "oops/instanceKlass.hpp"
40 #include "oops/klass.inline.hpp"
41 #include "oops/objArrayKlass.inline.hpp"
42 #include "oops/objArrayOop.inline.hpp"
43 #include "oops/oop.inline.hpp"
44 #include "oops/symbol.hpp"
45 #include "runtime/handles.inline.hpp"
46 #include "runtime/mutexLocker.hpp"
47 #include "utilities/macros.hpp"
48
49 ObjArrayKlass* ObjArrayKlass::allocate(ClassLoaderData* loader_data, int n, Klass* k, Symbol* name, TRAPS) {
50 assert(ObjArrayKlass::header_size() <= InstanceKlass::header_size(),
51 "array klasses must be same size as InstanceKlass");
52
53 int size = ArrayKlass::static_size(ObjArrayKlass::header_size());
54
55 return new (loader_data, size, THREAD) ObjArrayKlass(n, k, name);
56 }
57
58 Klass* ObjArrayKlass::allocate_objArray_klass(ArrayStorageProperties storage_props,
59 int n, Klass* element_klass, TRAPS) {
60 // Eagerly allocate the direct array supertype.
61 Klass* super_klass = NULL;
62 if (!Universe::is_bootstrapping() || SystemDictionary::Object_klass_loaded()) {
63 Klass* element_super = element_klass->super();
64 if (element_super != NULL) {
65 // The element type has a direct super. E.g., String[] has direct super of Object[].
66 super_klass = element_super->array_klass_or_null(ArrayStorageProperties::empty);
67 bool supers_exist = super_klass != NULL;
68 // Also, see if the element has secondary supertypes.
69 // We need an array type for each.
70 const Array<Klass*>* element_supers = element_klass->secondary_supers();
71 for( int i = element_supers->length()-1; i >= 0; i-- ) {
72 Klass* elem_super = element_supers->at(i);
73 if (elem_super->array_klass_or_null(ArrayStorageProperties::empty) == NULL) {
74 supers_exist = false;
75 break;
76 }
77 }
78 if (!supers_exist) {
79 // Oops. Not allocated yet. Back out, allocate it, and retry.
80 Klass* ek = NULL;
81 {
82 MutexUnlocker mu(MultiArray_lock);
83 super_klass = element_super->array_klass(CHECK_0);
84 for( int i = element_supers->length()-1; i >= 0; i-- ) {
85 Klass* elem_super = element_supers->at(i);
86 elem_super->array_klass(CHECK_0);
87 }
88 // Now retry from the beginning
89 ek = element_klass->array_klass(storage_props, n, CHECK_0);
90 } // re-lock
91 return ek;
92 }
93 } else {
94 // The element type is already Object. Object[] has direct super of Object.
95 super_klass = SystemDictionary::Object_klass();
96 }
97 }
98
99 // Create type name for klass.
100 Symbol* name = ArrayKlass::create_element_klass_array_name(storage_props.is_null_free(), element_klass, CHECK_NULL);
101
102 // Initialize instance variables
103 ClassLoaderData* loader_data = element_klass->class_loader_data();
104 ObjArrayKlass* oak = ObjArrayKlass::allocate(loader_data, n, element_klass, name, CHECK_0);
105
106 // Add all classes to our internal class loader list here,
107 // including classes in the bootstrap (NULL) class loader.
108 // GC walks these as strong roots.
109 loader_data->add_class(oak);
110
111 ModuleEntry* module = oak->module();
112 assert(module != NULL, "No module entry for array");
113
114 // Call complete_create_array_klass after all instance variables has been initialized.
115 ArrayKlass::complete_create_array_klass(oak, super_klass, module, CHECK_0);
116
117 return oak;
118 }
119
120 ObjArrayKlass::ObjArrayKlass(int n, Klass* element_klass, Symbol* name) : ArrayKlass(name, ID) {
121 this->set_dimension(n);
122 this->set_element_klass(element_klass);
123 // decrement refcount because object arrays are not explicitly freed. The
124 // InstanceKlass array_name() keeps the name counted while the klass is
125 // loaded.
126 name->decrement_refcount();
127
128 Klass* bk;
129 if (element_klass->is_objArray_klass()) {
130 bk = ObjArrayKlass::cast(element_klass)->bottom_klass();
131 } else if (element_klass->is_valueArray_klass()) {
132 bk = ValueArrayKlass::cast(element_klass)->element_klass();
133 } else {
134 bk = element_klass;
135 }
136 assert(bk != NULL && (bk->is_instance_klass()
137 || bk->is_typeArray_klass()), "invalid bottom klass");
138 this->set_bottom_klass(bk);
139 this->set_class_loader_data(bk->class_loader_data());
140
141 this->set_layout_helper(array_layout_helper(T_OBJECT));
142 assert(this->is_array_klass(), "sanity");
143 assert(this->is_objArray_klass(), "sanity");
144 }
145
146 int ObjArrayKlass::oop_size(oop obj) const {
147 assert(obj->is_objArray(), "must be object array");
148 return objArrayOop(obj)->object_size();
149 }
150
151 objArrayOop ObjArrayKlass::allocate(int length, TRAPS) {
152 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_0);
153 int size = objArrayOopDesc::object_size(length);
154 bool populate_null_free = storage_properties().is_null_free() && (dimension() == 1);
155 objArrayOop array = (objArrayOop)Universe::heap()->array_allocate(this, size, length,
156 /* do_zero */ true, THREAD);
157 if (populate_null_free) {
158 assert(element_klass()->is_value(), "Unexpected");
159 assert(!element_klass()->is_array_klass(), "ArrayKlass unexpected here");
160 element_klass()->initialize(CHECK_NULL);
161 // Populate default values...
162 objArrayHandle array_h(THREAD, array);
163 instanceOop value = (instanceOop) ValueKlass::cast(element_klass())->default_value();
164 for (int i = 0; i < length; i++) {
165 array_h->obj_at_put(i, value);
166 }
167 }
168 return array;
169 }
170
171 oop ObjArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) {
172 int length = *sizes;
173 if (rank == 1) { // last dim may be valueArray, check if we have any special storage requirements
174 if ((!element_klass()->is_array_klass()) && storage_properties().is_null_free()) {
175 return oopFactory::new_valueArray(element_klass(), length, CHECK_NULL);
176 } else {
177 return oopFactory::new_objArray(element_klass(), length, CHECK_NULL);
178 }
179 }
180 guarantee(rank > 1, "Rank below 1");
181 // Call to lower_dimension uses this pointer, so most be called before a
182 // possible GC
183 Klass* ld_klass = lower_dimension();
184 // If length < 0 allocate will throw an exception.
185 objArrayOop array = allocate(length, CHECK_NULL);
186 objArrayHandle h_array (THREAD, array);
187 if (length != 0) {
188 for (int index = 0; index < length; index++) {
189 ArrayKlass* ak = ArrayKlass::cast(ld_klass);
190 oop sub_array = ak->multi_allocate(rank-1, &sizes[1], CHECK_NULL);
191 h_array->obj_at_put(index, sub_array);
192 }
193 } else {
194 // Since this array dimension has zero length, nothing will be
195 // allocated, however the lower dimension values must be checked
196 // for illegal values.
197 for (int i = 0; i < rank - 1; ++i) {
198 sizes += 1;
199 if (*sizes < 0) {
200 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", *sizes));
201 }
202 }
203 }
204 return h_array();
205 }
206
207 ArrayStorageProperties ObjArrayKlass::storage_properties() {
208 return name()->is_Q_array_signature() ? ArrayStorageProperties::null_free : ArrayStorageProperties::empty;
209 }
210
211 // Either oop or narrowOop depending on UseCompressedOops.
212 void ObjArrayKlass::do_copy(arrayOop s, size_t src_offset,
213 arrayOop d, size_t dst_offset, int length, TRAPS) {
214 if (oopDesc::equals(s, d)) {
215 // since source and destination are equal we do not need conversion checks.
216 assert(length > 0, "sanity check");
217 ArrayAccess<>::oop_arraycopy(s, src_offset, d, dst_offset, length);
218 } else {
219 // We have to make sure all elements conform to the destination array
220 Klass* bound = ObjArrayKlass::cast(d->klass())->element_klass();
221 Klass* stype = ObjArrayKlass::cast(s->klass())->element_klass();
222 if (stype == bound || stype->is_subtype_of(bound)) {
223 // elements are guaranteed to be subtypes, so no check necessary
224 ArrayAccess<ARRAYCOPY_DISJOINT>::oop_arraycopy(s, src_offset, d, dst_offset, length);
225 } else {
226 // slow case: need individual subtype checks
227 // note: don't use obj_at_put below because it includes a redundant store check
228 if (!ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_CHECKCAST>::oop_arraycopy(s, src_offset, d, dst_offset, length)) {
229 ResourceMark rm(THREAD);
230 stringStream ss;
231 if (!bound->is_subtype_of(stype)) {
232 ss.print("arraycopy: type mismatch: can not copy %s[] into %s[]",
233 stype->external_name(), bound->external_name());
234 } else {
235 // oop_arraycopy should return the index in the source array that
236 // contains the problematic oop.
237 ss.print("arraycopy: element type mismatch: can not cast one of the elements"
238 " of %s[] to the type of the destination array, %s",
239 stype->external_name(), bound->external_name());
240 }
241 THROW_MSG(vmSymbols::java_lang_ArrayStoreException(), ss.as_string());
242 }
243 }
244 }
245 }
246
247 void ObjArrayKlass::copy_array(arrayOop s, int src_pos, arrayOop d,
248 int dst_pos, int length, TRAPS) {
249 assert(s->is_objArray(), "must be obj array");
250
251 if (EnableValhalla) {
252 if (d->is_valueArray()) {
253 ValueArrayKlass::cast(d->klass())->copy_array(s, src_pos, d, dst_pos, length, THREAD);
254 return;
255 }
256 }
257
258 if (!d->is_objArray()) {
259 ResourceMark rm(THREAD);
260 stringStream ss;
261 if (d->is_typeArray()) {
262 ss.print("arraycopy: type mismatch: can not copy object array[] into %s[]",
263 type2name_tab[ArrayKlass::cast(d->klass())->element_type()]);
264 } else {
265 ss.print("arraycopy: destination type %s is not an array", d->klass()->external_name());
266 }
267 THROW_MSG(vmSymbols::java_lang_ArrayStoreException(), ss.as_string());
268 }
269
270 // Check is all offsets and lengths are non negative
271 if (src_pos < 0 || dst_pos < 0 || length < 0) {
272 // Pass specific exception reason.
273 ResourceMark rm(THREAD);
274 stringStream ss;
275 if (src_pos < 0) {
276 ss.print("arraycopy: source index %d out of bounds for object array[%d]",
277 src_pos, s->length());
278 } else if (dst_pos < 0) {
279 ss.print("arraycopy: destination index %d out of bounds for object array[%d]",
280 dst_pos, d->length());
281 } else {
282 ss.print("arraycopy: length %d is negative", length);
283 }
284 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string());
285 }
286 // Check if the ranges are valid
287 if ((((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) ||
288 (((unsigned int) length + (unsigned int) dst_pos) > (unsigned int) d->length())) {
289 // Pass specific exception reason.
290 ResourceMark rm(THREAD);
291 stringStream ss;
292 if (((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) {
293 ss.print("arraycopy: last source index %u out of bounds for object array[%d]",
294 (unsigned int) length + (unsigned int) src_pos, s->length());
295 } else {
296 ss.print("arraycopy: last destination index %u out of bounds for object array[%d]",
297 (unsigned int) length + (unsigned int) dst_pos, d->length());
298 }
299 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string());
300 }
301
302 // Special case. Boundary cases must be checked first
303 // This allows the following call: copy_array(s, s.length(), d.length(), 0).
304 // This is correct, since the position is supposed to be an 'in between point', i.e., s.length(),
305 // points to the right of the last element.
306 if (length==0) {
307 return;
308 }
309 if (EnableValhalla && ArrayKlass::cast(d->klass())->element_klass()->is_value()) {
310 assert(d->is_objArray(), "Expected objArray");
311 ValueKlass* d_elem_vklass = ValueKlass::cast(ArrayKlass::cast(d->klass())->element_klass());
312 objArrayOop da = objArrayOop(d);
313 objArrayOop sa = objArrayOop(s);
314 int src_end = src_pos + length;
315 bool null_free = ArrayKlass::cast(s->klass())->storage_properties().is_null_free() ||
316 ArrayKlass::cast(d->klass())->storage_properties().is_null_free();
317 while (src_pos < src_end) {
318 oop se = sa->obj_at(src_pos);
319 if (null_free && se == NULL) {
320 THROW(vmSymbols::java_lang_NullPointerException());
321 }
322 // Check exact type per element
323 if (se != NULL && se->klass() != d_elem_vklass) {
324 THROW(vmSymbols::java_lang_ArrayStoreException());
325 }
326 da->obj_at_put(dst_pos, se); // TODO: review with ValueArrayKlass::copy_array and Access API
327 dst_pos++;
328 src_pos++;
329 }
330 } else if (UseCompressedOops) {
331 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(src_pos);
332 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(dst_pos);
333 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(s, src_offset, NULL) ==
334 objArrayOop(s)->obj_at_addr_raw<narrowOop>(src_pos), "sanity");
335 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(d, dst_offset, NULL) ==
336 objArrayOop(d)->obj_at_addr_raw<narrowOop>(dst_pos), "sanity");
337 do_copy(s, src_offset, d, dst_offset, length, CHECK);
338 } else {
339 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(src_pos);
340 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(dst_pos);
341 assert(arrayOopDesc::obj_offset_to_raw<oop>(s, src_offset, NULL) ==
342 objArrayOop(s)->obj_at_addr_raw<oop>(src_pos), "sanity");
343 assert(arrayOopDesc::obj_offset_to_raw<oop>(d, dst_offset, NULL) ==
344 objArrayOop(d)->obj_at_addr_raw<oop>(dst_pos), "sanity");
345 do_copy(s, src_offset, d, dst_offset, length, CHECK);
346 }
347 }
348
349
350 Klass* ObjArrayKlass::array_klass_impl(ArrayStorageProperties storage_props, bool or_null, int n, TRAPS) {
351 assert(!storage_props.is_flattened() || n > 1, "Cannot flatten");
352 assert(dimension() <= n, "check order of chain");
353 int dim = dimension();
354 if (dim == n) return this;
355
356 // lock-free read needs acquire semantics
357 if (higher_dimension_acquire() == NULL) {
358 if (or_null) return NULL;
359
360 ResourceMark rm;
361 {
362 // Ensure atomic creation of higher dimensions
363 MutexLocker mu(MultiArray_lock, THREAD);
364
365 // Check if another thread beat us
366 if (higher_dimension() == NULL) {
367
368 // Create multi-dim klass object and link them together
369 Klass* k = ObjArrayKlass::allocate_objArray_klass(storage_props, dim + 1, this, CHECK_NULL);
370 ObjArrayKlass* ak = ObjArrayKlass::cast(k);
371 ak->set_lower_dimension(this);
372 // use 'release' to pair with lock-free load
373 release_set_higher_dimension(ak);
374 assert(ak->is_objArray_klass(), "incorrect initialization of ObjArrayKlass");
375 }
376 }
377 } else {
378 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
379 }
380
381 ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension());
382 if (or_null) {
383 return ak->array_klass_or_null(storage_props, n);
384 }
385 return ak->array_klass(storage_props, n, THREAD);
386 }
387
388 Klass* ObjArrayKlass::array_klass_impl(ArrayStorageProperties storage_props, bool or_null, TRAPS) {
389 return array_klass_impl(storage_props, or_null, dimension() + 1, THREAD);
390 }
391
392 bool ObjArrayKlass::can_be_primary_super_slow() const {
393 if (!bottom_klass()->can_be_primary_super())
394 // array of interfaces
395 return false;
396 else
397 return Klass::can_be_primary_super_slow();
398 }
399
400 GrowableArray<Klass*>* ObjArrayKlass::compute_secondary_supers(int num_extra_slots,
401 Array<InstanceKlass*>* transitive_interfaces) {
402 assert(transitive_interfaces == NULL, "sanity");
403 // interfaces = { cloneable_klass, serializable_klass, elemSuper[], ... };
404 const Array<Klass*>* elem_supers = element_klass()->secondary_supers();
405 int num_elem_supers = elem_supers == NULL ? 0 : elem_supers->length();
406 int num_secondaries = num_extra_slots + 2 + num_elem_supers;
407 if (num_secondaries == 2) {
408 // Must share this for correct bootstrapping!
409 set_secondary_supers(Universe::the_array_interfaces_array());
410 return NULL;
411 } else {
412 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(num_elem_supers+2);
413 secondaries->push(SystemDictionary::Cloneable_klass());
414 secondaries->push(SystemDictionary::Serializable_klass());
415 for (int i = 0; i < num_elem_supers; i++) {
416 Klass* elem_super = elem_supers->at(i);
417 Klass* array_super = elem_super->array_klass_or_null(ArrayStorageProperties::empty);
418 assert(array_super != NULL, "must already have been created");
419 secondaries->push(array_super);
420 }
421 return secondaries;
422 }
423 }
424
425 void ObjArrayKlass::initialize(TRAPS) {
426 bottom_klass()->initialize(THREAD); // dispatches to either InstanceKlass or TypeArrayKlass
427 }
428
429 void ObjArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) {
430 ArrayKlass::metaspace_pointers_do(it);
431 it->push(&_element_klass);
432 it->push(&_bottom_klass);
433 }
434
435 // JVM support
436
437 jint ObjArrayKlass::compute_modifier_flags(TRAPS) const {
438 // The modifier for an objectArray is the same as its element
439 if (element_klass() == NULL) {
440 assert(Universe::is_bootstrapping(), "partial objArray only at startup");
441 return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
442 }
443 // Return the flags of the bottom element type.
444 jint element_flags = bottom_klass()->compute_modifier_flags(CHECK_0);
445
446 return (element_flags & (JVM_ACC_PUBLIC | JVM_ACC_PRIVATE | JVM_ACC_PROTECTED))
447 | (JVM_ACC_ABSTRACT | JVM_ACC_FINAL);
448 }
449
450 ModuleEntry* ObjArrayKlass::module() const {
451 assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass");
452 // The array is defined in the module of its bottom class
453 return bottom_klass()->module();
454 }
455
456 PackageEntry* ObjArrayKlass::package() const {
457 assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass");
458 return bottom_klass()->package();
459 }
460
461 // Printing
462
463 void ObjArrayKlass::print_on(outputStream* st) const {
464 #ifndef PRODUCT
465 Klass::print_on(st);
466 st->print(" - element klass: ");
467 element_klass()->print_value_on(st);
468 st->cr();
469 #endif //PRODUCT
470 }
471
472 void ObjArrayKlass::print_value_on(outputStream* st) const {
473 assert(is_klass(), "must be klass");
474
475 element_klass()->print_value_on(st);
476 st->print("[]");
477 }
478
479 #ifndef PRODUCT
480
481 void ObjArrayKlass::oop_print_on(oop obj, outputStream* st) {
482 ArrayKlass::oop_print_on(obj, st);
483 assert(obj->is_objArray(), "must be objArray");
484 objArrayOop oa = objArrayOop(obj);
485 int print_len = MIN2((intx) oa->length(), MaxElementPrintSize);
486 for(int index = 0; index < print_len; index++) {
487 st->print(" - %3d : ", index);
488 if (oa->obj_at(index) != NULL) {
489 oa->obj_at(index)->print_value_on(st);
490 st->cr();
491 } else {
492 st->print_cr("NULL");
493 }
494 }
495 int remaining = oa->length() - print_len;
496 if (remaining > 0) {
497 st->print_cr(" - <%d more elements, increase MaxElementPrintSize to print>", remaining);
498 }
499 }
500
501 #endif //PRODUCT
502
503 void ObjArrayKlass::oop_print_value_on(oop obj, outputStream* st) {
504 assert(obj->is_objArray(), "must be objArray");
505 st->print("a ");
506 element_klass()->print_value_on(st);
507 int len = objArrayOop(obj)->length();
508 st->print("[%d] ", len);
509 if (obj != NULL) {
510 obj->print_address_on(st);
511 } else {
512 st->print_cr("NULL");
513 }
514 }
515
516 const char* ObjArrayKlass::internal_name() const {
517 return external_name();
518 }
519
520
521 // Verification
522
523 void ObjArrayKlass::verify_on(outputStream* st) {
524 ArrayKlass::verify_on(st);
525 guarantee(element_klass()->is_klass(), "should be klass");
526 guarantee(bottom_klass()->is_klass(), "should be klass");
527 Klass* bk = bottom_klass();
528 guarantee(bk->is_instance_klass() || bk->is_typeArray_klass() || bk->is_valueArray_klass(),
529 "invalid bottom klass");
530 }
531
532 void ObjArrayKlass::oop_verify_on(oop obj, outputStream* st) {
533 ArrayKlass::oop_verify_on(obj, st);
534 guarantee(obj->is_objArray(), "must be objArray");
535 objArrayOop oa = objArrayOop(obj);
536 for(int index = 0; index < oa->length(); index++) {
537 guarantee(oopDesc::is_oop_or_null(oa->obj_at(index)), "should be oop");
538 }
539 }