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