1 /*
2 * Copyright (c) 1997, 2023, 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/vmClasses.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.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,
50 Klass* k, Symbol* name, bool null_free,
51 TRAPS) {
52 assert(ObjArrayKlass::header_size() <= InstanceKlass::header_size(),
53 "array klasses must be same size as InstanceKlass");
54
55 int size = ArrayKlass::static_size(ObjArrayKlass::header_size());
56
57 return new (loader_data, size, THREAD) ObjArrayKlass(n, k, name, null_free);
58 }
59
60 ObjArrayKlass* ObjArrayKlass::allocate_objArray_klass(ClassLoaderData* loader_data,
61 int n, Klass* element_klass,
62 bool null_free, TRAPS) {
63 assert(!null_free || (n == 1 && element_klass->is_inline_klass()), "null-free unsupported");
64
65 // Eagerly allocate the direct array supertype.
66 Klass* super_klass = nullptr;
67 if (!Universe::is_bootstrapping() || vmClasses::Object_klass_loaded()) {
68 Klass* element_super = element_klass->super();
69 if (element_super != nullptr) {
70 // The element type has a direct super. E.g., String[] has direct super of Object[].
71 if (null_free) {
72 super_klass = element_klass->array_klass_or_null();
73 } else {
74 super_klass = element_super->array_klass_or_null();
75 }
76 bool supers_exist = super_klass != nullptr;
77 // Also, see if the element has secondary supertypes.
78 // We need an array type for each.
79 const Array<Klass*>* element_supers = element_klass->secondary_supers();
80 for( int i = element_supers->length()-1; i >= 0; i-- ) {
81 Klass* elem_super = element_supers->at(i);
82 if (elem_super->array_klass_or_null() == nullptr) {
83 supers_exist = false;
84 break;
85 }
86 }
87 if (null_free) {
88 if (element_klass->array_klass_or_null() == nullptr) {
89 supers_exist = false;
90 }
91 }
92 if (!supers_exist) {
93 // Oops. Not allocated yet. Back out, allocate it, and retry.
94 Klass* ek = nullptr;
95 {
96 MutexUnlocker mu(MultiArray_lock);
97 if (null_free) {
98 element_klass->array_klass(CHECK_NULL);
99 } else {
100 element_super->array_klass(CHECK_NULL);
101 }
102 for( int i = element_supers->length()-1; i >= 0; i-- ) {
103 Klass* elem_super = element_supers->at(i);
104 elem_super->array_klass(CHECK_NULL);
105 }
106 // Now retry from the beginning
107 if (null_free) {
108 ek = InlineKlass::cast(element_klass)->value_array_klass(CHECK_NULL);
109 } else {
110 ek = element_klass->array_klass(n, CHECK_NULL);
111 }
112 } // re-lock
113 return ObjArrayKlass::cast(ek);
114 }
115 } else {
116 // The element type is already Object. Object[] has direct super of Object.
117 super_klass = vmClasses::Object_klass();
118 }
119 }
120
121 // Create type name for klass.
122 Symbol* name = ArrayKlass::create_element_klass_array_name(element_klass, CHECK_NULL);
123
124 // Initialize instance variables
125 ObjArrayKlass* oak = ObjArrayKlass::allocate(loader_data, n, element_klass, name, null_free, CHECK_NULL);
126
127 ModuleEntry* module = oak->module();
128 assert(module != nullptr, "No module entry for array");
129
130 // Call complete_create_array_klass after all instance variables has been initialized.
131 ArrayKlass::complete_create_array_klass(oak, super_klass, module, CHECK_NULL);
132
133 // Add all classes to our internal class loader list here,
134 // including classes in the bootstrap (null) class loader.
135 // Do this step after creating the mirror so that if the
136 // mirror creation fails, loaded_classes_do() doesn't find
137 // an array class without a mirror.
138 loader_data->add_class(oak);
139
140 return oak;
141 }
142
143 ObjArrayKlass::ObjArrayKlass(int n, Klass* element_klass, Symbol* name, bool null_free) : ArrayKlass(name, Kind) {
144 set_dimension(n);
145 set_element_klass(element_klass);
146
147 Klass* bk;
148 if (element_klass->is_objArray_klass()) {
149 bk = ObjArrayKlass::cast(element_klass)->bottom_klass();
150 } else if (element_klass->is_flatArray_klass()) {
151 bk = FlatArrayKlass::cast(element_klass)->element_klass();
152 } else {
153 bk = element_klass;
154 }
155 assert(bk != nullptr && (bk->is_instance_klass() || bk->is_typeArray_klass()), "invalid bottom klass");
156 set_bottom_klass(bk);
157 set_class_loader_data(bk->class_loader_data());
158
159 int lh = array_layout_helper(T_OBJECT);
160 if (null_free) {
161 assert(n == 1, "Bytecode does not support null-free multi-dim");
162 lh = layout_helper_set_null_free(lh);
163 #ifdef _LP64
164 set_prototype_header(markWord::null_free_array_prototype());
165 assert(prototype_header().is_null_free_array(), "sanity");
166 #else
167 set_prototype_header(markWord::inline_type_prototype());
168 #endif
169 }
170 set_layout_helper(lh);
171 assert(is_array_klass(), "sanity");
172 assert(is_objArray_klass(), "sanity");
173 }
174
175 size_t ObjArrayKlass::oop_size(oop obj) const {
176 assert(obj->is_objArray(), "must be object array");
177 return objArrayOop(obj)->object_size();
178 }
179
180 objArrayOop ObjArrayKlass::allocate(int length, TRAPS) {
181 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
182 size_t size = objArrayOopDesc::object_size(length);
183 bool populate_null_free = is_null_free_array_klass();
184 objArrayOop array = (objArrayOop)Universe::heap()->array_allocate(this, size, length,
185 /* do_zero */ true, CHECK_NULL);
186 objArrayHandle array_h(THREAD, array);
187 if (populate_null_free) {
188 assert(dimension() == 1, "Can only populate the final dimension");
189 assert(element_klass()->is_inline_klass(), "Unexpected");
190 assert(!element_klass()->is_array_klass(), "ArrayKlass unexpected here");
191 assert(!InlineKlass::cast(element_klass())->flat_array(), "Expected flatArrayOop allocation");
192 element_klass()->initialize(CHECK_NULL);
193 // Populate default values...
194 instanceOop value = (instanceOop) InlineKlass::cast(element_klass())->default_value();
195 for (int i = 0; i < length; i++) {
196 array_h->obj_at_put(i, value);
197 }
198 }
199 return array_h();
200 }
201
202 oop ObjArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) {
203 int length = *sizes;
204 ArrayKlass* ld_klass = lower_dimension();
205 // If length < 0 allocate will throw an exception.
206 objArrayOop array = allocate(length, CHECK_NULL);
207 objArrayHandle h_array (THREAD, array);
208 if (rank > 1) {
209 if (length != 0) {
210 for (int index = 0; index < length; index++) {
211 oop sub_array = ld_klass->multi_allocate(rank-1, &sizes[1], CHECK_NULL);
212 h_array->obj_at_put(index, sub_array);
213 }
214 } else {
215 // Since this array dimension has zero length, nothing will be
216 // allocated, however the lower dimension values must be checked
217 // for illegal values.
218 for (int i = 0; i < rank - 1; ++i) {
219 sizes += 1;
220 if (*sizes < 0) {
221 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", *sizes));
222 }
223 }
224 }
225 }
226 return h_array();
227 }
228
229 // Either oop or narrowOop depending on UseCompressedOops.
230 void ObjArrayKlass::do_copy(arrayOop s, size_t src_offset,
231 arrayOop d, size_t dst_offset, int length, TRAPS) {
232 if (s == d) {
233 // since source and destination are equal we do not need conversion checks.
234 assert(length > 0, "sanity check");
235 ArrayAccess<>::oop_arraycopy(s, src_offset, d, dst_offset, length);
236 } else {
237 // We have to make sure all elements conform to the destination array
238 Klass* bound = ObjArrayKlass::cast(d->klass())->element_klass();
239 Klass* stype = ObjArrayKlass::cast(s->klass())->element_klass();
240 // Perform null check if dst is null-free but src has no such guarantee
241 bool null_check = ((!s->klass()->is_null_free_array_klass()) &&
242 d->klass()->is_null_free_array_klass());
243 if (stype == bound || stype->is_subtype_of(bound)) {
244 if (null_check) {
245 ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_NOTNULL>::oop_arraycopy(s, src_offset, d, dst_offset, length);
246 } else {
247 ArrayAccess<ARRAYCOPY_DISJOINT>::oop_arraycopy(s, src_offset, d, dst_offset, length);
248 }
249 } else {
250 if (null_check) {
251 ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_CHECKCAST | ARRAYCOPY_NOTNULL>::oop_arraycopy(s, src_offset, d, dst_offset, length);
252 } else {
253 ArrayAccess<ARRAYCOPY_DISJOINT | ARRAYCOPY_CHECKCAST>::oop_arraycopy(s, src_offset, d, dst_offset, length);
254 }
255 }
256 }
257 }
258
259 void ObjArrayKlass::copy_array(arrayOop s, int src_pos, arrayOop d,
260 int dst_pos, int length, TRAPS) {
261 assert(s->is_objArray(), "must be obj array");
262
263 if (UseFlatArray) {
264 if (d->is_flatArray()) {
265 FlatArrayKlass::cast(d->klass())->copy_array(s, src_pos, d, dst_pos, length, THREAD);
266 return;
267 }
268 }
269
270 if (!d->is_objArray()) {
271 ResourceMark rm(THREAD);
272 stringStream ss;
273 if (d->is_typeArray()) {
274 ss.print("arraycopy: type mismatch: can not copy object array[] into %s[]",
275 type2name_tab[ArrayKlass::cast(d->klass())->element_type()]);
276 } else {
277 ss.print("arraycopy: destination type %s is not an array", d->klass()->external_name());
278 }
279 THROW_MSG(vmSymbols::java_lang_ArrayStoreException(), ss.as_string());
280 }
281
282 // Check is all offsets and lengths are non negative
283 if (src_pos < 0 || dst_pos < 0 || length < 0) {
284 // Pass specific exception reason.
285 ResourceMark rm(THREAD);
286 stringStream ss;
287 if (src_pos < 0) {
288 ss.print("arraycopy: source index %d out of bounds for object array[%d]",
289 src_pos, s->length());
290 } else if (dst_pos < 0) {
291 ss.print("arraycopy: destination index %d out of bounds for object array[%d]",
292 dst_pos, d->length());
293 } else {
294 ss.print("arraycopy: length %d is negative", length);
295 }
296 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string());
297 }
298 // Check if the ranges are valid
299 if ((((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) ||
300 (((unsigned int) length + (unsigned int) dst_pos) > (unsigned int) d->length())) {
301 // Pass specific exception reason.
302 ResourceMark rm(THREAD);
303 stringStream ss;
304 if (((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length()) {
305 ss.print("arraycopy: last source index %u out of bounds for object array[%d]",
306 (unsigned int) length + (unsigned int) src_pos, s->length());
307 } else {
308 ss.print("arraycopy: last destination index %u out of bounds for object array[%d]",
309 (unsigned int) length + (unsigned int) dst_pos, d->length());
310 }
311 THROW_MSG(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), ss.as_string());
312 }
313
314 // Special case. Boundary cases must be checked first
315 // This allows the following call: copy_array(s, s.length(), d.length(), 0).
316 // This is correct, since the position is supposed to be an 'in between point', i.e., s.length(),
317 // points to the right of the last element.
318 if (length==0) {
319 return;
320 }
321 if (UseCompressedOops) {
322 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(src_pos);
323 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<narrowOop>(dst_pos);
324 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(s, src_offset, nullptr) ==
325 objArrayOop(s)->obj_at_addr<narrowOop>(src_pos), "sanity");
326 assert(arrayOopDesc::obj_offset_to_raw<narrowOop>(d, dst_offset, nullptr) ==
327 objArrayOop(d)->obj_at_addr<narrowOop>(dst_pos), "sanity");
328 do_copy(s, src_offset, d, dst_offset, length, CHECK);
329 } else {
330 size_t src_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(src_pos);
331 size_t dst_offset = (size_t) objArrayOopDesc::obj_at_offset<oop>(dst_pos);
332 assert(arrayOopDesc::obj_offset_to_raw<oop>(s, src_offset, nullptr) ==
333 objArrayOop(s)->obj_at_addr<oop>(src_pos), "sanity");
334 assert(arrayOopDesc::obj_offset_to_raw<oop>(d, dst_offset, nullptr) ==
335 objArrayOop(d)->obj_at_addr<oop>(dst_pos), "sanity");
336 do_copy(s, src_offset, d, dst_offset, length, CHECK);
337 }
338 }
339
340 bool ObjArrayKlass::can_be_primary_super_slow() const {
341 if (!bottom_klass()->can_be_primary_super())
342 // array of interfaces
343 return false;
344 else
345 return Klass::can_be_primary_super_slow();
346 }
347
348 GrowableArray<Klass*>* ObjArrayKlass::compute_secondary_supers(int num_extra_slots,
349 Array<InstanceKlass*>* transitive_interfaces) {
350 assert(transitive_interfaces == nullptr, "sanity");
351 // interfaces = { cloneable_klass, serializable_klass, elemSuper[], ... };
352 const Array<Klass*>* elem_supers = element_klass()->secondary_supers();
353 int num_elem_supers = elem_supers == nullptr ? 0 : elem_supers->length();
354 int num_secondaries = num_extra_slots + 2 + num_elem_supers;
355 if (num_secondaries == 2) {
356 // Must share this for correct bootstrapping!
357 set_secondary_supers(Universe::the_array_interfaces_array());
358 return nullptr;
359 } else {
360 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(num_elem_supers+2);
361 secondaries->push(vmClasses::Cloneable_klass());
362 secondaries->push(vmClasses::Serializable_klass());
363 for (int i = 0; i < num_elem_supers; i++) {
364 Klass* elem_super = elem_supers->at(i);
365 Klass* array_super = elem_super->array_klass_or_null();
366 assert(array_super != nullptr, "must already have been created");
367 secondaries->push(array_super);
368 }
369 return secondaries;
370 }
371 }
372
373 void ObjArrayKlass::initialize(TRAPS) {
374 bottom_klass()->initialize(THREAD); // dispatches to either InstanceKlass or TypeArrayKlass
375 }
376
377 void ObjArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) {
378 ArrayKlass::metaspace_pointers_do(it);
379 it->push(&_element_klass);
380 it->push(&_bottom_klass);
381 }
382
383 jint ObjArrayKlass::compute_modifier_flags() const {
384 // The modifier for an objectArray is the same as its element
385 // With the addition of ACC_IDENTITY
386 if (element_klass() == nullptr) {
387 assert(Universe::is_bootstrapping(), "partial objArray only at startup");
388 return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
389 }
390 // Return the flags of the bottom element type.
391 jint element_flags = bottom_klass()->compute_modifier_flags();
392
393 int identity_flag = (Arguments::enable_preview()) ? JVM_ACC_IDENTITY : 0;
394
395 return (element_flags & (JVM_ACC_PUBLIC | JVM_ACC_PRIVATE | JVM_ACC_PROTECTED))
396 | (identity_flag | JVM_ACC_ABSTRACT | JVM_ACC_FINAL);
397 }
398
399 ModuleEntry* ObjArrayKlass::module() const {
400 assert(bottom_klass() != nullptr, "ObjArrayKlass returned unexpected null bottom_klass");
401 // The array is defined in the module of its bottom class
402 return bottom_klass()->module();
403 }
404
405 PackageEntry* ObjArrayKlass::package() const {
406 assert(bottom_klass() != nullptr, "ObjArrayKlass returned unexpected null bottom_klass");
407 return bottom_klass()->package();
408 }
409
410 // Printing
411
412 void ObjArrayKlass::print_on(outputStream* st) const {
413 #ifndef PRODUCT
414 Klass::print_on(st);
415 st->print(" - element klass: ");
416 element_klass()->print_value_on(st);
417 st->cr();
418 #endif //PRODUCT
419 }
420
421 void ObjArrayKlass::print_value_on(outputStream* st) const {
422 assert(is_klass(), "must be klass");
423
424 element_klass()->print_value_on(st);
425 st->print("[]");
426 }
427
428 #ifndef PRODUCT
429
430 void ObjArrayKlass::oop_print_on(oop obj, outputStream* st) {
431 ArrayKlass::oop_print_on(obj, st);
432 assert(obj->is_objArray(), "must be objArray");
433 objArrayOop oa = objArrayOop(obj);
434 int print_len = MIN2(oa->length(), MaxElementPrintSize);
435 for(int index = 0; index < print_len; index++) {
436 st->print(" - %3d : ", index);
437 if (oa->obj_at(index) != nullptr) {
438 oa->obj_at(index)->print_value_on(st);
439 st->cr();
440 } else {
441 st->print_cr("null");
442 }
443 }
444 int remaining = oa->length() - print_len;
445 if (remaining > 0) {
446 st->print_cr(" - <%d more elements, increase MaxElementPrintSize to print>", remaining);
447 }
448 }
449
450 #endif //PRODUCT
451
452 void ObjArrayKlass::oop_print_value_on(oop obj, outputStream* st) {
453 assert(obj->is_objArray(), "must be objArray");
454 st->print("a ");
455 element_klass()->print_value_on(st);
456 int len = objArrayOop(obj)->length();
457 st->print("[%d] ", len);
458 if (obj != nullptr) {
459 obj->print_address_on(st);
460 } else {
461 st->print_cr("null");
462 }
463 }
464
465 const char* ObjArrayKlass::internal_name() const {
466 return external_name();
467 }
468
469
470 // Verification
471
472 void ObjArrayKlass::verify_on(outputStream* st) {
473 ArrayKlass::verify_on(st);
474 guarantee(element_klass()->is_klass(), "should be klass");
475 guarantee(bottom_klass()->is_klass(), "should be klass");
476 Klass* bk = bottom_klass();
477 guarantee(bk->is_instance_klass() || bk->is_typeArray_klass() || bk->is_flatArray_klass(),
478 "invalid bottom klass");
479 }
480
481 void ObjArrayKlass::oop_verify_on(oop obj, outputStream* st) {
482 ArrayKlass::oop_verify_on(obj, st);
483 guarantee(obj->is_objArray(), "must be objArray");
484 guarantee(obj->is_null_free_array() || (!is_null_free_array_klass()), "null-free klass but not object");
485 objArrayOop oa = objArrayOop(obj);
486 for(int index = 0; index < oa->length(); index++) {
487 guarantee(oopDesc::is_oop_or_null(oa->obj_at(index)), "should be oop");
488 }
489 }