1 /*
2 * Copyright (c) 2018, 2025, 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 "cds/aotArtifactFinder.hpp"
26 #include "cds/aotClassInitializer.hpp"
27 #include "cds/aotClassLocation.hpp"
28 #include "cds/aotLogging.hpp"
29 #include "cds/aotReferenceObjSupport.hpp"
30 #include "cds/archiveBuilder.hpp"
31 #include "cds/archiveHeapLoader.hpp"
32 #include "cds/archiveHeapWriter.hpp"
33 #include "cds/archiveUtils.hpp"
34 #include "cds/cdsConfig.hpp"
35 #include "cds/cdsEnumKlass.hpp"
36 #include "cds/cdsHeapVerifier.hpp"
37 #include "cds/heapShared.hpp"
38 #include "cds/metaspaceShared.hpp"
39 #include "cds/regeneratedClasses.hpp"
40 #include "classfile/classLoaderData.hpp"
41 #include "classfile/javaClasses.inline.hpp"
42 #include "classfile/modules.hpp"
43 #include "classfile/stringTable.hpp"
44 #include "classfile/symbolTable.hpp"
45 #include "classfile/systemDictionary.hpp"
46 #include "classfile/systemDictionaryShared.hpp"
47 #include "classfile/vmClasses.hpp"
48 #include "classfile/vmSymbols.hpp"
49 #include "gc/shared/collectedHeap.hpp"
50 #include "gc/shared/gcLocker.hpp"
51 #include "gc/shared/gcVMOperations.hpp"
52 #include "logging/log.hpp"
53 #include "logging/logStream.hpp"
54 #include "memory/iterator.inline.hpp"
55 #include "memory/resourceArea.hpp"
56 #include "memory/universe.hpp"
57 #include "oops/compressedOops.inline.hpp"
58 #include "oops/fieldStreams.inline.hpp"
59 #include "oops/objArrayOop.inline.hpp"
60 #include "oops/oop.inline.hpp"
61 #include "oops/typeArrayOop.inline.hpp"
62 #include "prims/jvmtiExport.hpp"
63 #include "runtime/arguments.hpp"
64 #include "runtime/fieldDescriptor.inline.hpp"
65 #include "runtime/init.hpp"
66 #include "runtime/javaCalls.hpp"
67 #include "runtime/mutexLocker.hpp"
68 #include "runtime/safepointVerifiers.hpp"
69 #include "utilities/bitMap.inline.hpp"
70 #include "utilities/copy.hpp"
71 #if INCLUDE_G1GC
72 #include "gc/g1/g1CollectedHeap.hpp"
73 #endif
74
75 #if INCLUDE_CDS_JAVA_HEAP
76
77 struct ArchivableStaticFieldInfo {
78 const char* klass_name;
79 const char* field_name;
80 InstanceKlass* klass;
81 int offset;
82 BasicType type;
83
84 ArchivableStaticFieldInfo(const char* k, const char* f)
85 : klass_name(k), field_name(f), klass(nullptr), offset(0), type(T_ILLEGAL) {}
86
87 bool valid() {
88 return klass_name != nullptr;
89 }
90 };
91
92 DumpedInternedStrings *HeapShared::_dumped_interned_strings = nullptr;
93
94 size_t HeapShared::_alloc_count[HeapShared::ALLOC_STAT_SLOTS];
95 size_t HeapShared::_alloc_size[HeapShared::ALLOC_STAT_SLOTS];
96 size_t HeapShared::_total_obj_count;
97 size_t HeapShared::_total_obj_size;
98
99 #ifndef PRODUCT
100 #define ARCHIVE_TEST_FIELD_NAME "archivedObjects"
101 static Array<char>* _archived_ArchiveHeapTestClass = nullptr;
102 static const char* _test_class_name = nullptr;
103 static Klass* _test_class = nullptr;
104 static const ArchivedKlassSubGraphInfoRecord* _test_class_record = nullptr;
105 #endif
106
107
108 //
109 // If you add new entries to the following tables, you should know what you're doing!
110 //
111
112 static ArchivableStaticFieldInfo archive_subgraph_entry_fields[] = {
113 {"java/lang/Integer$IntegerCache", "archivedCache"},
114 {"java/lang/Long$LongCache", "archivedCache"},
115 {"java/lang/Byte$ByteCache", "archivedCache"},
116 {"java/lang/Short$ShortCache", "archivedCache"},
117 {"java/lang/Character$CharacterCache", "archivedCache"},
118 {"java/util/jar/Attributes$Name", "KNOWN_NAMES"},
119 {"sun/util/locale/BaseLocale", "constantBaseLocales"},
120 {"jdk/internal/module/ArchivedModuleGraph", "archivedModuleGraph"},
121 {"java/util/ImmutableCollections", "archivedObjects"},
122 {"java/lang/ModuleLayer", "EMPTY_LAYER"},
123 {"java/lang/module/Configuration", "EMPTY_CONFIGURATION"},
124 {"jdk/internal/math/FDBigInteger", "archivedCaches"},
125
126 #ifndef PRODUCT
127 {nullptr, nullptr}, // Extra slot for -XX:ArchiveHeapTestClass
128 #endif
129 {nullptr, nullptr},
130 };
131
132 // full module graph
133 static ArchivableStaticFieldInfo fmg_archive_subgraph_entry_fields[] = {
134 {"jdk/internal/loader/ArchivedClassLoaders", "archivedClassLoaders"},
135 {ARCHIVED_BOOT_LAYER_CLASS, ARCHIVED_BOOT_LAYER_FIELD},
136 {"java/lang/Module$ArchivedData", "archivedData"},
137 {nullptr, nullptr},
138 };
139
140 KlassSubGraphInfo* HeapShared::_dump_time_special_subgraph;
141 ArchivedKlassSubGraphInfoRecord* HeapShared::_run_time_special_subgraph;
142 GrowableArrayCHeap<oop, mtClassShared>* HeapShared::_pending_roots = nullptr;
143 GrowableArrayCHeap<OopHandle, mtClassShared>* HeapShared::_root_segments = nullptr;
144 int HeapShared::_root_segment_max_size_elems;
145 OopHandle HeapShared::_scratch_basic_type_mirrors[T_VOID+1];
146 MetaspaceObjToOopHandleTable* HeapShared::_scratch_objects_table = nullptr;
147
148 static bool is_subgraph_root_class_of(ArchivableStaticFieldInfo fields[], InstanceKlass* ik) {
149 for (int i = 0; fields[i].valid(); i++) {
150 if (fields[i].klass == ik) {
151 return true;
152 }
153 }
154 return false;
155 }
156
157 bool HeapShared::is_subgraph_root_class(InstanceKlass* ik) {
158 return is_subgraph_root_class_of(archive_subgraph_entry_fields, ik) ||
159 is_subgraph_root_class_of(fmg_archive_subgraph_entry_fields, ik);
160 }
161
162 unsigned HeapShared::oop_hash(oop const& p) {
163 // Do not call p->identity_hash() as that will update the
164 // object header.
165 return primitive_hash(cast_from_oop<intptr_t>(p));
166 }
167
168 static void reset_states(oop obj, TRAPS) {
169 Handle h_obj(THREAD, obj);
170 InstanceKlass* klass = InstanceKlass::cast(obj->klass());
171 TempNewSymbol method_name = SymbolTable::new_symbol("resetArchivedStates");
172 Symbol* method_sig = vmSymbols::void_method_signature();
173
174 while (klass != nullptr) {
175 Method* method = klass->find_method(method_name, method_sig);
176 if (method != nullptr) {
177 assert(method->is_private(), "must be");
178 if (log_is_enabled(Debug, aot)) {
179 ResourceMark rm(THREAD);
180 log_debug(aot)(" calling %s", method->name_and_sig_as_C_string());
181 }
182 JavaValue result(T_VOID);
183 JavaCalls::call_special(&result, h_obj, klass,
184 method_name, method_sig, CHECK);
185 }
186 klass = klass->java_super();
187 }
188 }
189
190 void HeapShared::reset_archived_object_states(TRAPS) {
191 assert(CDSConfig::is_dumping_heap(), "dump-time only");
192 log_debug(aot)("Resetting platform loader");
193 reset_states(SystemDictionary::java_platform_loader(), CHECK);
194 log_debug(aot)("Resetting system loader");
195 reset_states(SystemDictionary::java_system_loader(), CHECK);
196
197 // Clean up jdk.internal.loader.ClassLoaders::bootLoader(), which is not
198 // directly used for class loading, but rather is used by the core library
199 // to keep track of resources, etc, loaded by the null class loader.
200 //
201 // Note, this object is non-null, and is not the same as
202 // ClassLoaderData::the_null_class_loader_data()->class_loader(),
203 // which is null.
204 log_debug(aot)("Resetting boot loader");
205 JavaValue result(T_OBJECT);
206 JavaCalls::call_static(&result,
207 vmClasses::jdk_internal_loader_ClassLoaders_klass(),
208 vmSymbols::bootLoader_name(),
209 vmSymbols::void_BuiltinClassLoader_signature(),
210 CHECK);
211 Handle boot_loader(THREAD, result.get_oop());
212 reset_states(boot_loader(), CHECK);
213 }
214
215 HeapShared::ArchivedObjectCache* HeapShared::_archived_object_cache = nullptr;
216
217 bool HeapShared::has_been_archived(oop obj) {
218 assert(CDSConfig::is_dumping_heap(), "dump-time only");
219 return archived_object_cache()->get(obj) != nullptr;
220 }
221
222 int HeapShared::append_root(oop obj) {
223 assert(CDSConfig::is_dumping_heap(), "dump-time only");
224 if (obj != nullptr) {
225 assert(has_been_archived(obj), "must be");
226 }
227 // No GC should happen since we aren't scanning _pending_roots.
228 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
229
230 return _pending_roots->append(obj);
231 }
232
233 objArrayOop HeapShared::root_segment(int segment_idx) {
234 if (CDSConfig::is_dumping_heap()) {
235 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
236 } else {
237 assert(CDSConfig::is_using_archive(), "must be");
238 }
239
240 objArrayOop segment = (objArrayOop)_root_segments->at(segment_idx).resolve();
241 assert(segment != nullptr, "should have been initialized");
242 return segment;
243 }
244
245 void HeapShared::get_segment_indexes(int idx, int& seg_idx, int& int_idx) {
246 assert(_root_segment_max_size_elems > 0, "sanity");
247
248 // Try to avoid divisions for the common case.
249 if (idx < _root_segment_max_size_elems) {
250 seg_idx = 0;
251 int_idx = idx;
252 } else {
253 seg_idx = idx / _root_segment_max_size_elems;
254 int_idx = idx % _root_segment_max_size_elems;
255 }
256
257 assert(idx == seg_idx * _root_segment_max_size_elems + int_idx,
258 "sanity: %d index maps to %d segment and %d internal", idx, seg_idx, int_idx);
259 }
260
261 // Returns an objArray that contains all the roots of the archived objects
262 oop HeapShared::get_root(int index, bool clear) {
263 assert(index >= 0, "sanity");
264 assert(!CDSConfig::is_dumping_heap() && CDSConfig::is_using_archive(), "runtime only");
265 assert(!_root_segments->is_empty(), "must have loaded shared heap");
266 int seg_idx, int_idx;
267 get_segment_indexes(index, seg_idx, int_idx);
268 oop result = root_segment(seg_idx)->obj_at(int_idx);
269 if (clear) {
270 clear_root(index);
271 }
272 return result;
273 }
274
275 void HeapShared::clear_root(int index) {
276 assert(index >= 0, "sanity");
277 assert(CDSConfig::is_using_archive(), "must be");
278 if (ArchiveHeapLoader::is_in_use()) {
279 int seg_idx, int_idx;
280 get_segment_indexes(index, seg_idx, int_idx);
281 if (log_is_enabled(Debug, aot, heap)) {
282 oop old = root_segment(seg_idx)->obj_at(int_idx);
283 log_debug(aot, heap)("Clearing root %d: was " PTR_FORMAT, index, p2i(old));
284 }
285 root_segment(seg_idx)->obj_at_put(int_idx, nullptr);
286 }
287 }
288
289 bool HeapShared::archive_object(oop obj, oop referrer, KlassSubGraphInfo* subgraph_info) {
290 assert(CDSConfig::is_dumping_heap(), "dump-time only");
291
292 assert(!obj->is_stackChunk(), "do not archive stack chunks");
293 if (has_been_archived(obj)) {
294 return true;
295 }
296
297 if (ArchiveHeapWriter::is_too_large_to_archive(obj->size())) {
298 log_debug(aot, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: %zu",
299 p2i(obj), obj->size());
300 debug_trace();
301 return false;
302 } else {
303 count_allocation(obj->size());
304 ArchiveHeapWriter::add_source_obj(obj);
305 CachedOopInfo info = make_cached_oop_info(obj, referrer);
306 archived_object_cache()->put_when_absent(obj, info);
307 archived_object_cache()->maybe_grow();
308 mark_native_pointers(obj);
309
310 Klass* k = obj->klass();
311 if (k->is_instance_klass()) {
312 // Whenever we see a non-array Java object of type X, we mark X to be aot-initialized.
313 // This ensures that during the production run, whenever Java code sees a cached object
314 // of type X, we know that X is already initialized. (see TODO comment below ...)
315
316 if (InstanceKlass::cast(k)->is_enum_subclass()
317 // We can't rerun <clinit> of enum classes (see cdsEnumKlass.cpp) so
318 // we must store them as AOT-initialized.
319 || (subgraph_info == _dump_time_special_subgraph))
320 // TODO: we do this only for the special subgraph for now. Extending this to
321 // other subgraphs would require more refactoring of the core library (such as
322 // move some initialization logic into runtimeSetup()).
323 //
324 // For the other subgraphs, we have a weaker mechanism to ensure that
325 // all classes in a subgraph are initialized before the subgraph is programmatically
326 // returned from jdk.internal.misc.CDS::initializeFromArchive().
327 // See HeapShared::initialize_from_archived_subgraph().
328 {
329 AOTArtifactFinder::add_aot_inited_class(InstanceKlass::cast(k));
330 }
331
332 if (java_lang_Class::is_instance(obj)) {
333 Klass* mirror_k = java_lang_Class::as_Klass(obj);
334 if (mirror_k != nullptr) {
335 AOTArtifactFinder::add_cached_class(mirror_k);
336 }
337 } else if (java_lang_invoke_ResolvedMethodName::is_instance(obj)) {
338 Method* m = java_lang_invoke_ResolvedMethodName::vmtarget(obj);
339 if (m != nullptr) {
340 if (RegeneratedClasses::has_been_regenerated(m)) {
341 m = RegeneratedClasses::get_regenerated_object(m);
342 }
343 InstanceKlass* method_holder = m->method_holder();
344 AOTArtifactFinder::add_cached_class(method_holder);
345 }
346 }
347 }
348
349 if (log_is_enabled(Debug, aot, heap)) {
350 ResourceMark rm;
351 LogTarget(Debug, aot, heap) log;
352 LogStream out(log);
353 out.print("Archived heap object " PTR_FORMAT " : %s ",
354 p2i(obj), obj->klass()->external_name());
355 if (java_lang_Class::is_instance(obj)) {
356 Klass* k = java_lang_Class::as_Klass(obj);
357 if (k != nullptr) {
358 out.print("%s", k->external_name());
359 } else {
360 out.print("primitive");
361 }
362 }
363 out.cr();
364 }
365
366 return true;
367 }
368 }
369
370 class MetaspaceObjToOopHandleTable: public ResourceHashtable<MetaspaceObj*, OopHandle,
371 36137, // prime number
372 AnyObj::C_HEAP,
373 mtClassShared> {
374 public:
375 oop get_oop(MetaspaceObj* ptr) {
376 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
377 OopHandle* handle = get(ptr);
378 if (handle != nullptr) {
379 return handle->resolve();
380 } else {
381 return nullptr;
382 }
383 }
384 void set_oop(MetaspaceObj* ptr, oop o) {
385 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
386 OopHandle handle(Universe::vm_global(), o);
387 bool is_new = put(ptr, handle);
388 assert(is_new, "cannot set twice");
389 }
390 void remove_oop(MetaspaceObj* ptr) {
391 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
392 OopHandle* handle = get(ptr);
393 if (handle != nullptr) {
394 handle->release(Universe::vm_global());
395 remove(ptr);
396 }
397 }
398 };
399
400 void HeapShared::add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) {
401 if (SystemDictionaryShared::is_builtin_loader(src->pool_holder()->class_loader_data())) {
402 _scratch_objects_table->set_oop(src, dest);
403 }
404 }
405
406 objArrayOop HeapShared::scratch_resolved_references(ConstantPool* src) {
407 return (objArrayOop)_scratch_objects_table->get_oop(src);
408 }
409
410 void HeapShared::init_dumping() {
411 _scratch_objects_table = new (mtClass)MetaspaceObjToOopHandleTable();
412 _pending_roots = new GrowableArrayCHeap<oop, mtClassShared>(500);
413 }
414
415 void HeapShared::init_scratch_objects_for_basic_type_mirrors(TRAPS) {
416 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
417 BasicType bt = (BasicType)i;
418 if (!is_reference_type(bt)) {
419 oop m = java_lang_Class::create_basic_type_mirror(type2name(bt), bt, true, CHECK);
420 _scratch_basic_type_mirrors[i] = OopHandle(Universe::vm_global(), m);
421 }
422 }
423 }
424
425 // Given java_mirror that represents a (primitive or reference) type T,
426 // return the "scratch" version that represents the same type T.
427 // Note that if java_mirror will be returned if it's already a
428 // scratch mirror.
429 //
430 // See java_lang_Class::create_scratch_mirror() for more info.
431 oop HeapShared::scratch_java_mirror(oop java_mirror) {
432 assert(java_lang_Class::is_instance(java_mirror), "must be");
433
434 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
435 BasicType bt = (BasicType)i;
436 if (!is_reference_type(bt)) {
437 if (_scratch_basic_type_mirrors[i].resolve() == java_mirror) {
438 return java_mirror;
439 }
440 }
441 }
442
443 if (java_lang_Class::is_primitive(java_mirror)) {
444 return scratch_java_mirror(java_lang_Class::as_BasicType(java_mirror));
445 } else {
446 return scratch_java_mirror(java_lang_Class::as_Klass(java_mirror));
447 }
448 }
449
450 oop HeapShared::scratch_java_mirror(BasicType t) {
451 assert((uint)t < T_VOID+1, "range check");
452 assert(!is_reference_type(t), "sanity");
453 return _scratch_basic_type_mirrors[t].resolve();
454 }
455
456 oop HeapShared::scratch_java_mirror(Klass* k) {
457 return _scratch_objects_table->get_oop(k);
458 }
459
460 void HeapShared::set_scratch_java_mirror(Klass* k, oop mirror) {
461 _scratch_objects_table->set_oop(k, mirror);
462 }
463
464 void HeapShared::remove_scratch_objects(Klass* k) {
465 // Klass is being deallocated. Java mirror can still be alive, and it should not
466 // point to dead klass. We need to break the link from mirror to the Klass.
467 // See how InstanceKlass::deallocate_contents does it for normal mirrors.
468 oop mirror = _scratch_objects_table->get_oop(k);
469 if (mirror != nullptr) {
470 java_lang_Class::set_klass(mirror, nullptr);
471 }
472 _scratch_objects_table->remove_oop(k);
473 if (k->is_instance_klass()) {
474 _scratch_objects_table->remove(InstanceKlass::cast(k)->constants());
475 }
476 }
477
478 //TODO: we eventually want a more direct test for these kinds of things.
479 //For example the JVM could record some bit of context from the creation
480 //of the klass, such as who called the hidden class factory. Using
481 //string compares on names is fragile and will break as soon as somebody
482 //changes the names in the JDK code. See discussion in JDK-8342481 for
483 //related ideas about marking AOT-related classes.
484 bool HeapShared::is_lambda_form_klass(InstanceKlass* ik) {
485 return ik->is_hidden() &&
486 (ik->name()->starts_with("java/lang/invoke/LambdaForm$MH+") ||
487 ik->name()->starts_with("java/lang/invoke/LambdaForm$DMH+") ||
488 ik->name()->starts_with("java/lang/invoke/LambdaForm$BMH+") ||
489 ik->name()->starts_with("java/lang/invoke/LambdaForm$VH+"));
490 }
491
492 bool HeapShared::is_lambda_proxy_klass(InstanceKlass* ik) {
493 return ik->is_hidden() && (ik->name()->index_of_at(0, "$$Lambda+", 9) > 0);
494 }
495
496 bool HeapShared::is_string_concat_klass(InstanceKlass* ik) {
497 return ik->is_hidden() && ik->name()->starts_with("java/lang/String$$StringConcat");
498 }
499
500 bool HeapShared::is_archivable_hidden_klass(InstanceKlass* ik) {
501 return CDSConfig::is_dumping_method_handles() &&
502 (is_lambda_form_klass(ik) || is_lambda_proxy_klass(ik) || is_string_concat_klass(ik));
503 }
504
505
506 void HeapShared::copy_and_rescan_aot_inited_mirror(InstanceKlass* ik) {
507 ik->set_has_aot_initialized_mirror();
508 if (AOTClassInitializer::is_runtime_setup_required(ik)) {
509 ik->set_is_runtime_setup_required();
510 }
511
512 oop orig_mirror;
513 if (RegeneratedClasses::is_regenerated_object(ik)) {
514 InstanceKlass* orig_ik = RegeneratedClasses::get_original_object(ik);
515 precond(orig_ik->is_initialized());
516 orig_mirror = orig_ik->java_mirror();
517 } else {
518 precond(ik->is_initialized());
519 orig_mirror = ik->java_mirror();
520 }
521
522 oop m = scratch_java_mirror(ik);
523 int nfields = 0;
524 for (JavaFieldStream fs(ik); !fs.done(); fs.next()) {
525 if (fs.access_flags().is_static()) {
526 fieldDescriptor& fd = fs.field_descriptor();
527 int offset = fd.offset();
528 switch (fd.field_type()) {
529 case T_OBJECT:
530 case T_ARRAY:
531 {
532 oop field_obj = orig_mirror->obj_field(offset);
533 if (offset == java_lang_Class::reflection_data_offset()) {
534 // Class::reflectData use SoftReference, which cannot be archived. Set it
535 // to null and it will be recreated at runtime.
536 field_obj = nullptr;
537 }
538 m->obj_field_put(offset, field_obj);
539 if (field_obj != nullptr) {
540 bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, field_obj);
541 assert(success, "sanity");
542 }
543 }
544 break;
545 case T_BOOLEAN:
546 m->bool_field_put(offset, orig_mirror->bool_field(offset));
547 break;
548 case T_BYTE:
549 m->byte_field_put(offset, orig_mirror->byte_field(offset));
550 break;
551 case T_SHORT:
552 m->short_field_put(offset, orig_mirror->short_field(offset));
553 break;
554 case T_CHAR:
555 m->char_field_put(offset, orig_mirror->char_field(offset));
556 break;
557 case T_INT:
558 m->int_field_put(offset, orig_mirror->int_field(offset));
559 break;
560 case T_LONG:
561 m->long_field_put(offset, orig_mirror->long_field(offset));
562 break;
563 case T_FLOAT:
564 m->float_field_put(offset, orig_mirror->float_field(offset));
565 break;
566 case T_DOUBLE:
567 m->double_field_put(offset, orig_mirror->double_field(offset));
568 break;
569 default:
570 ShouldNotReachHere();
571 }
572 nfields ++;
573 }
574 }
575
576 oop class_data = java_lang_Class::class_data(orig_mirror);
577 java_lang_Class::set_class_data(m, class_data);
578 if (class_data != nullptr) {
579 bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, class_data);
580 assert(success, "sanity");
581 }
582
583 if (log_is_enabled(Debug, aot, init)) {
584 ResourceMark rm;
585 log_debug(aot, init)("copied %3d field(s) in aot-initialized mirror %s%s%s", nfields, ik->external_name(),
586 ik->is_hidden() ? " (hidden)" : "",
587 ik->is_enum_subclass() ? " (enum)" : "");
588 }
589 }
590
591 static void copy_java_mirror_hashcode(oop orig_mirror, oop scratch_m) {
592 // We need to retain the identity_hash, because it may have been used by some hashtables
593 // in the shared heap.
594 assert(!UseCompactObjectHeaders || scratch_m->mark().is_not_hashed_expanded(), "scratch mirror must have not-hashed-expanded state");
595 if (!orig_mirror->fast_no_hash_check()) {
596 intptr_t orig_mark = orig_mirror->mark().value();
597 intptr_t src_hash = orig_mirror->identity_hash();
598 if (UseCompactObjectHeaders) {
599 // We leave the cases not_hashed/not_hashed_expanded as they are.
600 assert(orig_mirror->mark().is_hashed_not_expanded() || orig_mirror->mark().is_hashed_expanded(), "must be hashed");
601 Klass* orig_klass = orig_mirror->klass();
602 narrowKlass nk = CompressedKlassPointers::encode(orig_klass);
603 markWord mark = markWord::prototype().set_narrow_klass(nk);
604 mark = mark.copy_hashctrl_from(orig_mirror->mark());
605 if (mark.is_hashed_not_expanded()) {
606 scratch_m->initialize_hash_if_necessary(orig_mirror, orig_klass, mark);
607 } else {
608 assert(mark.is_hashed_expanded(), "must be hashed & moved");
609 int offset = orig_klass->hash_offset_in_bytes(orig_mirror, mark);
610 assert(offset >= 8, "hash offset must not be in header");
611 scratch_m->int_field_put(offset, (jint) src_hash);
612 scratch_m->set_mark(mark);
613 }
614 assert(scratch_m->mark().is_hashed_expanded(), "must be hashed & moved");
615 assert(scratch_m->mark().is_not_hashed_expanded() || scratch_m->mark().is_hashed_expanded(), "must be not hashed and expanded");
616 } else {
617 scratch_m->set_mark(markWord::prototype().copy_set_hash(src_hash));
618 DEBUG_ONLY(intptr_t archived_hash = scratch_m->identity_hash());
619 assert(src_hash == archived_hash, "Different hash codes: original " INTPTR_FORMAT ", archived " INTPTR_FORMAT, src_hash, archived_hash);
620 }
621 assert(scratch_m->mark().is_unlocked(), "sanity");
622 }
623 }
624
625 static objArrayOop get_archived_resolved_references(InstanceKlass* src_ik) {
626 if (SystemDictionaryShared::is_builtin_loader(src_ik->class_loader_data())) {
627 objArrayOop rr = src_ik->constants()->resolved_references_or_null();
628 if (rr != nullptr && !ArchiveHeapWriter::is_too_large_to_archive(rr)) {
629 return HeapShared::scratch_resolved_references(src_ik->constants());
630 }
631 }
632 return nullptr;
633 }
634
635 void HeapShared::archive_strings() {
636 oop shared_strings_array = StringTable::init_shared_strings_array();
637 bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, shared_strings_array);
638 assert(success, "shared strings array must not point to arrays or strings that are too large to archive");
639 StringTable::set_shared_strings_array_index(append_root(shared_strings_array));
640 }
641
642 int HeapShared::archive_exception_instance(oop exception) {
643 bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, exception);
644 assert(success, "sanity");
645 return append_root(exception);
646 }
647
648 void HeapShared::mark_native_pointers(oop orig_obj) {
649 if (java_lang_Class::is_instance(orig_obj)) {
650 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::klass_offset());
651 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::array_klass_offset());
652 } else if (java_lang_invoke_ResolvedMethodName::is_instance(orig_obj)) {
653 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_invoke_ResolvedMethodName::vmtarget_offset());
654 }
655 }
656
657 void HeapShared::get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers) {
658 CachedOopInfo* info = archived_object_cache()->get(src_obj);
659 assert(info != nullptr, "must be");
660 has_oop_pointers = info->has_oop_pointers();
661 has_native_pointers = info->has_native_pointers();
662 }
663
664 void HeapShared::set_has_native_pointers(oop src_obj) {
665 CachedOopInfo* info = archived_object_cache()->get(src_obj);
666 assert(info != nullptr, "must be");
667 info->set_has_native_pointers();
668 }
669
670 // Between start_scanning_for_oops() and end_scanning_for_oops(), we discover all Java heap objects that
671 // should be stored in the AOT cache. The scanning is coordinated by AOTArtifactFinder.
672 void HeapShared::start_scanning_for_oops() {
673 {
674 NoSafepointVerifier nsv;
675
676 // The special subgraph doesn't belong to any class. We use Object_klass() here just
677 // for convenience.
678 _dump_time_special_subgraph = init_subgraph_info(vmClasses::Object_klass(), false);
679
680 // Cache for recording where the archived objects are copied to
681 create_archived_object_cache();
682
683 if (UseCompressedOops || UseG1GC) {
684 aot_log_info(aot)("Heap range = [" PTR_FORMAT " - " PTR_FORMAT "]",
685 UseCompressedOops ? p2i(CompressedOops::begin()) :
686 p2i((address)G1CollectedHeap::heap()->reserved().start()),
687 UseCompressedOops ? p2i(CompressedOops::end()) :
688 p2i((address)G1CollectedHeap::heap()->reserved().end()));
689 }
690
691 archive_subgraphs();
692 }
693
694 init_seen_objects_table();
695 Universe::archive_exception_instances();
696 }
697
698 void HeapShared::end_scanning_for_oops() {
699 archive_strings();
700 delete_seen_objects_table();
701 }
702
703 void HeapShared::write_heap(ArchiveHeapInfo *heap_info) {
704 {
705 NoSafepointVerifier nsv;
706 CDSHeapVerifier::verify();
707 check_special_subgraph_classes();
708 }
709
710 StringTable::write_shared_table();
711 ArchiveHeapWriter::write(_pending_roots, heap_info);
712
713 ArchiveBuilder::OtherROAllocMark mark;
714 write_subgraph_info_table();
715 }
716
717 void HeapShared::scan_java_mirror(oop orig_mirror) {
718 oop m = scratch_java_mirror(orig_mirror);
719 if (m != nullptr) { // nullptr if for custom class loader
720 copy_java_mirror_hashcode(orig_mirror, m);
721 bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, m);
722 assert(success, "sanity");
723 }
724 }
725
726 void HeapShared::scan_java_class(Klass* orig_k) {
727 scan_java_mirror(orig_k->java_mirror());
728
729 if (orig_k->is_instance_klass()) {
730 InstanceKlass* orig_ik = InstanceKlass::cast(orig_k);
731 orig_ik->constants()->prepare_resolved_references_for_archiving();
732 objArrayOop rr = get_archived_resolved_references(orig_ik);
733 if (rr != nullptr) {
734 bool success = HeapShared::archive_reachable_objects_from(1, _dump_time_special_subgraph, rr);
735 assert(success, "must be");
736 }
737 }
738 }
739
740 void HeapShared::archive_subgraphs() {
741 assert(CDSConfig::is_dumping_heap(), "must be");
742
743 archive_object_subgraphs(archive_subgraph_entry_fields,
744 false /* is_full_module_graph */);
745
746 if (CDSConfig::is_dumping_full_module_graph()) {
747 archive_object_subgraphs(fmg_archive_subgraph_entry_fields,
748 true /* is_full_module_graph */);
749 Modules::verify_archived_modules();
750 }
751 }
752
753 //
754 // Subgraph archiving support
755 //
756 HeapShared::DumpTimeKlassSubGraphInfoTable* HeapShared::_dump_time_subgraph_info_table = nullptr;
757 HeapShared::RunTimeKlassSubGraphInfoTable HeapShared::_run_time_subgraph_info_table;
758
759 // Get the subgraph_info for Klass k. A new subgraph_info is created if
760 // there is no existing one for k. The subgraph_info records the "buffered"
761 // address of the class.
762 KlassSubGraphInfo* HeapShared::init_subgraph_info(Klass* k, bool is_full_module_graph) {
763 assert(CDSConfig::is_dumping_heap(), "dump time only");
764 bool created;
765 KlassSubGraphInfo* info =
766 _dump_time_subgraph_info_table->put_if_absent(k, KlassSubGraphInfo(k, is_full_module_graph),
767 &created);
768 assert(created, "must not initialize twice");
769 return info;
770 }
771
772 KlassSubGraphInfo* HeapShared::get_subgraph_info(Klass* k) {
773 assert(CDSConfig::is_dumping_heap(), "dump time only");
774 KlassSubGraphInfo* info = _dump_time_subgraph_info_table->get(k);
775 assert(info != nullptr, "must have been initialized");
776 return info;
777 }
778
779 // Add an entry field to the current KlassSubGraphInfo.
780 void KlassSubGraphInfo::add_subgraph_entry_field(int static_field_offset, oop v) {
781 assert(CDSConfig::is_dumping_heap(), "dump time only");
782 if (_subgraph_entry_fields == nullptr) {
783 _subgraph_entry_fields =
784 new (mtClass) GrowableArray<int>(10, mtClass);
785 }
786 _subgraph_entry_fields->append(static_field_offset);
787 _subgraph_entry_fields->append(HeapShared::append_root(v));
788 }
789
790 // Add the Klass* for an object in the current KlassSubGraphInfo's subgraphs.
791 // Only objects of boot classes can be included in sub-graph.
792 void KlassSubGraphInfo::add_subgraph_object_klass(Klass* orig_k) {
793 assert(CDSConfig::is_dumping_heap(), "dump time only");
794
795 if (_subgraph_object_klasses == nullptr) {
796 _subgraph_object_klasses =
797 new (mtClass) GrowableArray<Klass*>(50, mtClass);
798 }
799
800 if (_k == orig_k) {
801 // Don't add the Klass containing the sub-graph to it's own klass
802 // initialization list.
803 return;
804 }
805
806 if (orig_k->is_instance_klass()) {
807 #ifdef ASSERT
808 InstanceKlass* ik = InstanceKlass::cast(orig_k);
809 if (CDSConfig::is_dumping_method_handles()) {
810 // -XX:AOTInitTestClass must be used carefully in regression tests to
811 // include only classes that are safe to aot-initialize.
812 assert(ik->class_loader() == nullptr ||
813 HeapShared::is_lambda_proxy_klass(ik) ||
814 AOTClassInitializer::has_test_class(),
815 "we can archive only instances of boot classes or lambda proxy classes");
816 } else {
817 assert(ik->class_loader() == nullptr, "must be boot class");
818 }
819 #endif
820 // vmClasses::xxx_klass() are not updated, need to check
821 // the original Klass*
822 if (orig_k == vmClasses::String_klass() ||
823 orig_k == vmClasses::Object_klass()) {
824 // Initialized early during VM initialization. No need to be added
825 // to the sub-graph object class list.
826 return;
827 }
828 check_allowed_klass(InstanceKlass::cast(orig_k));
829 } else if (orig_k->is_objArray_klass()) {
830 Klass* abk = ObjArrayKlass::cast(orig_k)->bottom_klass();
831 if (abk->is_instance_klass()) {
832 assert(InstanceKlass::cast(abk)->defined_by_boot_loader(),
833 "must be boot class");
834 check_allowed_klass(InstanceKlass::cast(ObjArrayKlass::cast(orig_k)->bottom_klass()));
835 }
836 if (orig_k == Universe::objectArrayKlass()) {
837 // Initialized early during Universe::genesis. No need to be added
838 // to the list.
839 return;
840 }
841 } else {
842 assert(orig_k->is_typeArray_klass(), "must be");
843 // Primitive type arrays are created early during Universe::genesis.
844 return;
845 }
846
847 if (log_is_enabled(Debug, aot, heap)) {
848 if (!_subgraph_object_klasses->contains(orig_k)) {
849 ResourceMark rm;
850 log_debug(aot, heap)("Adding klass %s", orig_k->external_name());
851 }
852 }
853
854 _subgraph_object_klasses->append_if_missing(orig_k);
855 _has_non_early_klasses |= is_non_early_klass(orig_k);
856 }
857
858 void KlassSubGraphInfo::check_allowed_klass(InstanceKlass* ik) {
859 #ifndef PRODUCT
860 if (AOTClassInitializer::has_test_class()) {
861 // The tests can cache arbitrary types of objects.
862 return;
863 }
864 #endif
865
866 if (ik->module()->name() == vmSymbols::java_base()) {
867 assert(ik->package() != nullptr, "classes in java.base cannot be in unnamed package");
868 return;
869 }
870
871 const char* lambda_msg = "";
872 if (CDSConfig::is_dumping_method_handles()) {
873 lambda_msg = ", or a lambda proxy class";
874 if (HeapShared::is_lambda_proxy_klass(ik) &&
875 (ik->class_loader() == nullptr ||
876 ik->class_loader() == SystemDictionary::java_platform_loader() ||
877 ik->class_loader() == SystemDictionary::java_system_loader())) {
878 return;
879 }
880 }
881
882 #ifndef PRODUCT
883 if (!ik->module()->is_named() && ik->package() == nullptr && ArchiveHeapTestClass != nullptr) {
884 // This class is loaded by ArchiveHeapTestClass
885 return;
886 }
887 const char* testcls_msg = ", or a test class in an unnamed package of an unnamed module";
888 #else
889 const char* testcls_msg = "";
890 #endif
891
892 ResourceMark rm;
893 log_error(aot, heap)("Class %s not allowed in archive heap. Must be in java.base%s%s",
894 ik->external_name(), lambda_msg, testcls_msg);
895 MetaspaceShared::unrecoverable_writing_error();
896 }
897
898 bool KlassSubGraphInfo::is_non_early_klass(Klass* k) {
899 if (k->is_objArray_klass()) {
900 k = ObjArrayKlass::cast(k)->bottom_klass();
901 }
902 if (k->is_instance_klass()) {
903 if (!SystemDictionaryShared::is_early_klass(InstanceKlass::cast(k))) {
904 ResourceMark rm;
905 log_info(aot, heap)("non-early: %s", k->external_name());
906 return true;
907 } else {
908 return false;
909 }
910 } else {
911 return false;
912 }
913 }
914
915 // Initialize an archived subgraph_info_record from the given KlassSubGraphInfo.
916 void ArchivedKlassSubGraphInfoRecord::init(KlassSubGraphInfo* info) {
917 _k = ArchiveBuilder::get_buffered_klass(info->klass());
918 _entry_field_records = nullptr;
919 _subgraph_object_klasses = nullptr;
920 _is_full_module_graph = info->is_full_module_graph();
921
922 if (_is_full_module_graph) {
923 // Consider all classes referenced by the full module graph as early -- we will be
924 // allocating objects of these classes during JVMTI early phase, so they cannot
925 // be processed by (non-early) JVMTI ClassFileLoadHook
926 _has_non_early_klasses = false;
927 } else {
928 _has_non_early_klasses = info->has_non_early_klasses();
929 }
930
931 if (_has_non_early_klasses) {
932 ResourceMark rm;
933 log_info(aot, heap)(
934 "Subgraph of klass %s has non-early klasses and cannot be used when JVMTI ClassFileLoadHook is enabled",
935 _k->external_name());
936 }
937
938 // populate the entry fields
939 GrowableArray<int>* entry_fields = info->subgraph_entry_fields();
940 if (entry_fields != nullptr) {
941 int num_entry_fields = entry_fields->length();
942 assert(num_entry_fields % 2 == 0, "sanity");
943 _entry_field_records =
944 ArchiveBuilder::new_ro_array<int>(num_entry_fields);
945 for (int i = 0 ; i < num_entry_fields; i++) {
946 _entry_field_records->at_put(i, entry_fields->at(i));
947 }
948 }
949
950 // <recorded_klasses> has the Klasses of all the objects that are referenced by this subgraph.
951 // Copy those that need to be explicitly initialized into <_subgraph_object_klasses>.
952 GrowableArray<Klass*>* recorded_klasses = info->subgraph_object_klasses();
953 if (recorded_klasses != nullptr) {
954 // AOT-inited classes are automatically marked as "initialized" during bootstrap. When
955 // programmatically loading a subgraph, we only need to explicitly initialize the classes
956 // that are not aot-inited.
957 int num_to_copy = 0;
958 for (int i = 0; i < recorded_klasses->length(); i++) {
959 Klass* subgraph_k = ArchiveBuilder::get_buffered_klass(recorded_klasses->at(i));
960 if (!subgraph_k->has_aot_initialized_mirror()) {
961 num_to_copy ++;
962 }
963 }
964
965 _subgraph_object_klasses = ArchiveBuilder::new_ro_array<Klass*>(num_to_copy);
966 bool is_special = (_k == ArchiveBuilder::get_buffered_klass(vmClasses::Object_klass()));
967 for (int i = 0, n = 0; i < recorded_klasses->length(); i++) {
968 Klass* subgraph_k = ArchiveBuilder::get_buffered_klass(recorded_klasses->at(i));
969 if (subgraph_k->has_aot_initialized_mirror()) {
970 continue;
971 }
972 if (log_is_enabled(Info, aot, heap)) {
973 ResourceMark rm;
974 const char* owner_name = is_special ? "<special>" : _k->external_name();
975 if (subgraph_k->is_instance_klass()) {
976 InstanceKlass* src_ik = InstanceKlass::cast(ArchiveBuilder::current()->get_source_addr(subgraph_k));
977 }
978 log_info(aot, heap)(
979 "Archived object klass %s (%2d) => %s",
980 owner_name, n, subgraph_k->external_name());
981 }
982 _subgraph_object_klasses->at_put(n, subgraph_k);
983 ArchivePtrMarker::mark_pointer(_subgraph_object_klasses->adr_at(n));
984 n++;
985 }
986 }
987
988 ArchivePtrMarker::mark_pointer(&_k);
989 ArchivePtrMarker::mark_pointer(&_entry_field_records);
990 ArchivePtrMarker::mark_pointer(&_subgraph_object_klasses);
991 }
992
993 class HeapShared::CopyKlassSubGraphInfoToArchive : StackObj {
994 CompactHashtableWriter* _writer;
995 public:
996 CopyKlassSubGraphInfoToArchive(CompactHashtableWriter* writer) : _writer(writer) {}
997
998 bool do_entry(Klass* klass, KlassSubGraphInfo& info) {
999 if (info.subgraph_object_klasses() != nullptr || info.subgraph_entry_fields() != nullptr) {
1000 ArchivedKlassSubGraphInfoRecord* record = HeapShared::archive_subgraph_info(&info);
1001 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(klass);
1002 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary((address)buffered_k);
1003 u4 delta = ArchiveBuilder::current()->any_to_offset_u4(record);
1004 _writer->add(hash, delta);
1005 }
1006 return true; // keep on iterating
1007 }
1008 };
1009
1010 ArchivedKlassSubGraphInfoRecord* HeapShared::archive_subgraph_info(KlassSubGraphInfo* info) {
1011 ArchivedKlassSubGraphInfoRecord* record =
1012 (ArchivedKlassSubGraphInfoRecord*)ArchiveBuilder::ro_region_alloc(sizeof(ArchivedKlassSubGraphInfoRecord));
1013 record->init(info);
1014 if (info == _dump_time_special_subgraph) {
1015 _run_time_special_subgraph = record;
1016 }
1017 return record;
1018 }
1019
1020 // Build the records of archived subgraph infos, which include:
1021 // - Entry points to all subgraphs from the containing class mirror. The entry
1022 // points are static fields in the mirror. For each entry point, the field
1023 // offset, and value are recorded in the sub-graph
1024 // info. The value is stored back to the corresponding field at runtime.
1025 // - A list of klasses that need to be loaded/initialized before archived
1026 // java object sub-graph can be accessed at runtime.
1027 void HeapShared::write_subgraph_info_table() {
1028 // Allocate the contents of the hashtable(s) inside the RO region of the CDS archive.
1029 DumpTimeKlassSubGraphInfoTable* d_table = _dump_time_subgraph_info_table;
1030 CompactHashtableStats stats;
1031
1032 _run_time_subgraph_info_table.reset();
1033
1034 CompactHashtableWriter writer(d_table->_count, &stats);
1035 CopyKlassSubGraphInfoToArchive copy(&writer);
1036 d_table->iterate(©);
1037 writer.dump(&_run_time_subgraph_info_table, "subgraphs");
1038
1039 #ifndef PRODUCT
1040 if (ArchiveHeapTestClass != nullptr) {
1041 size_t len = strlen(ArchiveHeapTestClass) + 1;
1042 Array<char>* array = ArchiveBuilder::new_ro_array<char>((int)len);
1043 strncpy(array->adr_at(0), ArchiveHeapTestClass, len);
1044 _archived_ArchiveHeapTestClass = array;
1045 }
1046 #endif
1047 if (log_is_enabled(Info, aot, heap)) {
1048 print_stats();
1049 }
1050 }
1051
1052 void HeapShared::add_root_segment(objArrayOop segment_oop) {
1053 assert(segment_oop != nullptr, "must be");
1054 assert(ArchiveHeapLoader::is_in_use(), "must be");
1055 if (_root_segments == nullptr) {
1056 _root_segments = new GrowableArrayCHeap<OopHandle, mtClassShared>(10);
1057 }
1058 _root_segments->push(OopHandle(Universe::vm_global(), segment_oop));
1059 }
1060
1061 void HeapShared::init_root_segment_sizes(int max_size_elems) {
1062 _root_segment_max_size_elems = max_size_elems;
1063 }
1064
1065 void HeapShared::serialize_tables(SerializeClosure* soc) {
1066
1067 #ifndef PRODUCT
1068 soc->do_ptr(&_archived_ArchiveHeapTestClass);
1069 if (soc->reading() && _archived_ArchiveHeapTestClass != nullptr) {
1070 _test_class_name = _archived_ArchiveHeapTestClass->adr_at(0);
1071 setup_test_class(_test_class_name);
1072 }
1073 #endif
1074
1075 _run_time_subgraph_info_table.serialize_header(soc);
1076 soc->do_ptr(&_run_time_special_subgraph);
1077 }
1078
1079 static void verify_the_heap(Klass* k, const char* which) {
1080 if (VerifyArchivedFields > 0) {
1081 ResourceMark rm;
1082 log_info(aot, heap)("Verify heap %s initializing static field(s) in %s",
1083 which, k->external_name());
1084
1085 VM_Verify verify_op;
1086 VMThread::execute(&verify_op);
1087
1088 if (VerifyArchivedFields > 1 && is_init_completed()) {
1089 // At this time, the oop->klass() of some archived objects in the heap may not
1090 // have been loaded into the system dictionary yet. Nevertheless, oop->klass() should
1091 // have enough information (object size, oop maps, etc) so that a GC can be safely
1092 // performed.
1093 //
1094 // -XX:VerifyArchivedFields=2 force a GC to happen in such an early stage
1095 // to check for GC safety.
1096 log_info(aot, heap)("Trigger GC %s initializing static field(s) in %s",
1097 which, k->external_name());
1098 FlagSetting fs1(VerifyBeforeGC, true);
1099 FlagSetting fs2(VerifyDuringGC, true);
1100 FlagSetting fs3(VerifyAfterGC, true);
1101 Universe::heap()->collect(GCCause::_java_lang_system_gc);
1102 }
1103 }
1104 }
1105
1106 // Before GC can execute, we must ensure that all oops reachable from HeapShared::roots()
1107 // have a valid klass. I.e., oopDesc::klass() must have already been resolved.
1108 //
1109 // Note: if a ArchivedKlassSubGraphInfoRecord contains non-early classes, and JVMTI
1110 // ClassFileLoadHook is enabled, it's possible for this class to be dynamically replaced. In
1111 // this case, we will not load the ArchivedKlassSubGraphInfoRecord and will clear its roots.
1112 void HeapShared::resolve_classes(JavaThread* current) {
1113 assert(CDSConfig::is_using_archive(), "runtime only!");
1114 if (!ArchiveHeapLoader::is_in_use()) {
1115 return; // nothing to do
1116 }
1117 resolve_classes_for_subgraphs(current, archive_subgraph_entry_fields);
1118 resolve_classes_for_subgraphs(current, fmg_archive_subgraph_entry_fields);
1119 }
1120
1121 void HeapShared::resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]) {
1122 for (int i = 0; fields[i].valid(); i++) {
1123 ArchivableStaticFieldInfo* info = &fields[i];
1124 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
1125 InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name);
1126 assert(k != nullptr && k->defined_by_boot_loader(), "sanity");
1127 resolve_classes_for_subgraph_of(current, k);
1128 }
1129 }
1130
1131 void HeapShared::resolve_classes_for_subgraph_of(JavaThread* current, Klass* k) {
1132 JavaThread* THREAD = current;
1133 ExceptionMark em(THREAD);
1134 const ArchivedKlassSubGraphInfoRecord* record =
1135 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD);
1136 if (HAS_PENDING_EXCEPTION) {
1137 CLEAR_PENDING_EXCEPTION;
1138 }
1139 if (record == nullptr) {
1140 clear_archived_roots_of(k);
1141 }
1142 }
1143
1144 void HeapShared::initialize_java_lang_invoke(TRAPS) {
1145 if (CDSConfig::is_using_aot_linked_classes() || CDSConfig::is_dumping_method_handles()) {
1146 resolve_or_init("java/lang/invoke/Invokers$Holder", true, CHECK);
1147 resolve_or_init("java/lang/invoke/MethodHandle", true, CHECK);
1148 resolve_or_init("java/lang/invoke/MethodHandleNatives", true, CHECK);
1149 resolve_or_init("java/lang/invoke/DirectMethodHandle$Holder", true, CHECK);
1150 resolve_or_init("java/lang/invoke/DelegatingMethodHandle$Holder", true, CHECK);
1151 resolve_or_init("java/lang/invoke/LambdaForm$Holder", true, CHECK);
1152 resolve_or_init("java/lang/invoke/BoundMethodHandle$Species_L", true, CHECK);
1153 }
1154 }
1155
1156 // Initialize the InstanceKlasses of objects that are reachable from the following roots:
1157 // - interned strings
1158 // - Klass::java_mirror() -- including aot-initialized mirrors such as those of Enum klasses.
1159 // - ConstantPool::resolved_references()
1160 // - Universe::<xxx>_exception_instance()
1161 //
1162 // For example, if this enum class is initialized at AOT cache assembly time:
1163 //
1164 // enum Fruit {
1165 // APPLE, ORANGE, BANANA;
1166 // static final Set<Fruit> HAVE_SEEDS = new HashSet<>(Arrays.asList(APPLE, ORANGE));
1167 // }
1168 //
1169 // the aot-initialized mirror of Fruit has a static field that references HashSet, which
1170 // should be initialized before any Java code can access the Fruit class. Note that
1171 // HashSet itself doesn't necessary need to be an aot-initialized class.
1172 void HeapShared::init_classes_for_special_subgraph(Handle class_loader, TRAPS) {
1173 if (!ArchiveHeapLoader::is_in_use()) {
1174 return;
1175 }
1176
1177 assert( _run_time_special_subgraph != nullptr, "must be");
1178 Array<Klass*>* klasses = _run_time_special_subgraph->subgraph_object_klasses();
1179 if (klasses != nullptr) {
1180 for (int pass = 0; pass < 2; pass ++) {
1181 for (int i = 0; i < klasses->length(); i++) {
1182 Klass* k = klasses->at(i);
1183 if (k->class_loader_data() == nullptr) {
1184 // This class is not yet loaded. We will initialize it in a later phase.
1185 // For example, we have loaded only AOTLinkedClassCategory::BOOT1 classes
1186 // but k is part of AOTLinkedClassCategory::BOOT2.
1187 continue;
1188 }
1189 if (k->class_loader() == class_loader()) {
1190 if (pass == 0) {
1191 if (k->is_instance_klass()) {
1192 InstanceKlass::cast(k)->link_class(CHECK);
1193 }
1194 } else {
1195 resolve_or_init(k, /*do_init*/true, CHECK);
1196 }
1197 }
1198 }
1199 }
1200 }
1201 }
1202
1203 void HeapShared::initialize_from_archived_subgraph(JavaThread* current, Klass* k) {
1204 JavaThread* THREAD = current;
1205 if (!ArchiveHeapLoader::is_in_use()) {
1206 return; // nothing to do
1207 }
1208
1209 if (k->name()->equals("jdk/internal/module/ArchivedModuleGraph") &&
1210 !CDSConfig::is_using_optimized_module_handling() &&
1211 // archive was created with --module-path
1212 AOTClassLocationConfig::runtime()->num_module_paths() > 0) {
1213 // ArchivedModuleGraph was created with a --module-path that's different than the runtime --module-path.
1214 // Thus, it might contain references to modules that do not exist at runtime. We cannot use it.
1215 log_info(aot, heap)("Skip initializing ArchivedModuleGraph subgraph: is_using_optimized_module_handling=%s num_module_paths=%d",
1216 BOOL_TO_STR(CDSConfig::is_using_optimized_module_handling()),
1217 AOTClassLocationConfig::runtime()->num_module_paths());
1218 return;
1219 }
1220
1221 ExceptionMark em(THREAD);
1222 const ArchivedKlassSubGraphInfoRecord* record =
1223 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD);
1224
1225 if (HAS_PENDING_EXCEPTION) {
1226 CLEAR_PENDING_EXCEPTION;
1227 // None of the field value will be set if there was an exception when initializing the classes.
1228 // The java code will not see any of the archived objects in the
1229 // subgraphs referenced from k in this case.
1230 return;
1231 }
1232
1233 if (record != nullptr) {
1234 init_archived_fields_for(k, record);
1235 }
1236 }
1237
1238 const ArchivedKlassSubGraphInfoRecord*
1239 HeapShared::resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS) {
1240 assert(!CDSConfig::is_dumping_heap(), "Should not be called when dumping heap");
1241
1242 if (!k->is_shared()) {
1243 return nullptr;
1244 }
1245 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k);
1246 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
1247
1248 #ifndef PRODUCT
1249 if (_test_class_name != nullptr && k->name()->equals(_test_class_name) && record != nullptr) {
1250 _test_class = k;
1251 _test_class_record = record;
1252 }
1253 #endif
1254
1255 // Initialize from archived data. Currently this is done only
1256 // during VM initialization time. No lock is needed.
1257 if (record == nullptr) {
1258 if (log_is_enabled(Info, aot, heap)) {
1259 ResourceMark rm(THREAD);
1260 log_info(aot, heap)("subgraph %s is not recorded",
1261 k->external_name());
1262 }
1263 return nullptr;
1264 } else {
1265 if (record->is_full_module_graph() && !CDSConfig::is_using_full_module_graph()) {
1266 if (log_is_enabled(Info, aot, heap)) {
1267 ResourceMark rm(THREAD);
1268 log_info(aot, heap)("subgraph %s cannot be used because full module graph is disabled",
1269 k->external_name());
1270 }
1271 return nullptr;
1272 }
1273
1274 if (record->has_non_early_klasses() && JvmtiExport::should_post_class_file_load_hook()) {
1275 if (log_is_enabled(Info, aot, heap)) {
1276 ResourceMark rm(THREAD);
1277 log_info(aot, heap)("subgraph %s cannot be used because JVMTI ClassFileLoadHook is enabled",
1278 k->external_name());
1279 }
1280 return nullptr;
1281 }
1282
1283 if (log_is_enabled(Info, aot, heap)) {
1284 ResourceMark rm;
1285 log_info(aot, heap)("%s subgraph %s ", do_init ? "init" : "resolve", k->external_name());
1286 }
1287
1288 resolve_or_init(k, do_init, CHECK_NULL);
1289
1290 // Load/link/initialize the klasses of the objects in the subgraph.
1291 // nullptr class loader is used.
1292 Array<Klass*>* klasses = record->subgraph_object_klasses();
1293 if (klasses != nullptr) {
1294 for (int i = 0; i < klasses->length(); i++) {
1295 Klass* klass = klasses->at(i);
1296 if (!klass->is_shared()) {
1297 return nullptr;
1298 }
1299 resolve_or_init(klass, do_init, CHECK_NULL);
1300 }
1301 }
1302 }
1303
1304 return record;
1305 }
1306
1307 void HeapShared::resolve_or_init(const char* klass_name, bool do_init, TRAPS) {
1308 TempNewSymbol klass_name_sym = SymbolTable::new_symbol(klass_name);
1309 InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name_sym);
1310 if (k == nullptr) {
1311 return;
1312 }
1313 assert(k->defined_by_boot_loader(), "sanity");
1314 resolve_or_init(k, false, CHECK);
1315 if (do_init) {
1316 resolve_or_init(k, true, CHECK);
1317 }
1318 }
1319
1320 void HeapShared::resolve_or_init(Klass* k, bool do_init, TRAPS) {
1321 if (!do_init) {
1322 if (k->class_loader_data() == nullptr) {
1323 Klass* resolved_k = SystemDictionary::resolve_or_null(k->name(), CHECK);
1324 assert(resolved_k == k, "classes used by archived heap must not be replaced by JVMTI ClassFileLoadHook");
1325 }
1326 } else {
1327 assert(k->class_loader_data() != nullptr, "must have been resolved by HeapShared::resolve_classes");
1328 if (k->is_instance_klass()) {
1329 InstanceKlass* ik = InstanceKlass::cast(k);
1330 ik->initialize(CHECK);
1331 } else if (k->is_objArray_klass()) {
1332 ObjArrayKlass* oak = ObjArrayKlass::cast(k);
1333 oak->initialize(CHECK);
1334 }
1335 }
1336 }
1337
1338 void HeapShared::init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record) {
1339 verify_the_heap(k, "before");
1340
1341 // Load the subgraph entry fields from the record and store them back to
1342 // the corresponding fields within the mirror.
1343 oop m = k->java_mirror();
1344 Array<int>* entry_field_records = record->entry_field_records();
1345 if (entry_field_records != nullptr) {
1346 int efr_len = entry_field_records->length();
1347 assert(efr_len % 2 == 0, "sanity");
1348 for (int i = 0; i < efr_len; i += 2) {
1349 int field_offset = entry_field_records->at(i);
1350 int root_index = entry_field_records->at(i+1);
1351 oop v = get_root(root_index, /*clear=*/true);
1352 if (k->has_aot_initialized_mirror()) {
1353 assert(v == m->obj_field(field_offset), "must be aot-initialized");
1354 } else {
1355 m->obj_field_put(field_offset, v);
1356 }
1357 log_debug(aot, heap)(" " PTR_FORMAT " init field @ %2d = " PTR_FORMAT, p2i(k), field_offset, p2i(v));
1358 }
1359
1360 // Done. Java code can see the archived sub-graphs referenced from k's
1361 // mirror after this point.
1362 if (log_is_enabled(Info, aot, heap)) {
1363 ResourceMark rm;
1364 log_info(aot, heap)("initialize_from_archived_subgraph %s " PTR_FORMAT "%s%s",
1365 k->external_name(), p2i(k), JvmtiExport::is_early_phase() ? " (early)" : "",
1366 k->has_aot_initialized_mirror() ? " (aot-inited)" : "");
1367 }
1368 }
1369
1370 verify_the_heap(k, "after ");
1371 }
1372
1373 void HeapShared::clear_archived_roots_of(Klass* k) {
1374 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k);
1375 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
1376 if (record != nullptr) {
1377 Array<int>* entry_field_records = record->entry_field_records();
1378 if (entry_field_records != nullptr) {
1379 int efr_len = entry_field_records->length();
1380 assert(efr_len % 2 == 0, "sanity");
1381 for (int i = 0; i < efr_len; i += 2) {
1382 int root_index = entry_field_records->at(i+1);
1383 clear_root(root_index);
1384 }
1385 }
1386 }
1387 }
1388
1389 // Push all oop fields (or oop array elemenets in case of an objArray) in
1390 // _referencing_obj onto the _stack.
1391 class HeapShared::OopFieldPusher: public BasicOopIterateClosure {
1392 PendingOopStack* _stack;
1393 GrowableArray<oop> _found_oop_fields;
1394 int _level;
1395 bool _record_klasses_only;
1396 KlassSubGraphInfo* _subgraph_info;
1397 oop _referencing_obj;
1398 bool _is_java_lang_ref;
1399 public:
1400 OopFieldPusher(PendingOopStack* stack,
1401 int level,
1402 bool record_klasses_only,
1403 KlassSubGraphInfo* subgraph_info,
1404 oop orig) :
1405 _stack(stack),
1406 _found_oop_fields(),
1407 _level(level),
1408 _record_klasses_only(record_klasses_only),
1409 _subgraph_info(subgraph_info),
1410 _referencing_obj(orig) {
1411 _is_java_lang_ref = AOTReferenceObjSupport::check_if_ref_obj(orig);
1412 }
1413 void do_oop(narrowOop *p) { OopFieldPusher::do_oop_work(p); }
1414 void do_oop( oop *p) { OopFieldPusher::do_oop_work(p); }
1415
1416 ~OopFieldPusher() {
1417 while (_found_oop_fields.length() > 0) {
1418 // This produces the exact same traversal order as the previous version
1419 // of OopFieldPusher that recurses on the C stack -- a depth-first search,
1420 // walking the oop fields in _referencing_obj by ascending field offsets.
1421 oop obj = _found_oop_fields.pop();
1422 _stack->push(PendingOop(obj, _referencing_obj, _level + 1));
1423 }
1424 }
1425
1426 protected:
1427 template <class T> void do_oop_work(T *p) {
1428 int field_offset = pointer_delta_as_int((char*)p, cast_from_oop<char*>(_referencing_obj));
1429 oop obj = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(_referencing_obj, field_offset);
1430 if (!CompressedOops::is_null(obj)) {
1431 if (_is_java_lang_ref && AOTReferenceObjSupport::skip_field(field_offset)) {
1432 // Do not follow these fields. They will be cleared to null.
1433 return;
1434 }
1435
1436 if (!_record_klasses_only && log_is_enabled(Debug, aot, heap)) {
1437 ResourceMark rm;
1438 log_debug(aot, heap)("(%d) %s[%d] ==> " PTR_FORMAT " size %zu %s", _level,
1439 _referencing_obj->klass()->external_name(), field_offset,
1440 p2i(obj), obj->size() * HeapWordSize, obj->klass()->external_name());
1441 if (log_is_enabled(Trace, aot, heap)) {
1442 LogTarget(Trace, aot, heap) log;
1443 LogStream out(log);
1444 obj->print_on(&out);
1445 }
1446 }
1447
1448 _found_oop_fields.push(obj);
1449 }
1450 }
1451
1452 public:
1453 oop referencing_obj() { return _referencing_obj; }
1454 KlassSubGraphInfo* subgraph_info() { return _subgraph_info; }
1455 };
1456
1457 // Checks if an oop has any non-null oop fields
1458 class PointsToOopsChecker : public BasicOopIterateClosure {
1459 bool _result;
1460
1461 template <class T> void check(T *p) {
1462 _result |= (HeapAccess<>::oop_load(p) != nullptr);
1463 }
1464
1465 public:
1466 PointsToOopsChecker() : _result(false) {}
1467 void do_oop(narrowOop *p) { check(p); }
1468 void do_oop( oop *p) { check(p); }
1469 bool result() { return _result; }
1470 };
1471
1472 HeapShared::CachedOopInfo HeapShared::make_cached_oop_info(oop obj, oop referrer) {
1473 PointsToOopsChecker points_to_oops_checker;
1474 obj->oop_iterate(&points_to_oops_checker);
1475 return CachedOopInfo(referrer, points_to_oops_checker.result());
1476 }
1477
1478 void HeapShared::init_box_classes(TRAPS) {
1479 if (ArchiveHeapLoader::is_in_use()) {
1480 vmClasses::Boolean_klass()->initialize(CHECK);
1481 vmClasses::Character_klass()->initialize(CHECK);
1482 vmClasses::Float_klass()->initialize(CHECK);
1483 vmClasses::Double_klass()->initialize(CHECK);
1484 vmClasses::Byte_klass()->initialize(CHECK);
1485 vmClasses::Short_klass()->initialize(CHECK);
1486 vmClasses::Integer_klass()->initialize(CHECK);
1487 vmClasses::Long_klass()->initialize(CHECK);
1488 vmClasses::Void_klass()->initialize(CHECK);
1489 }
1490 }
1491
1492 // (1) If orig_obj has not been archived yet, archive it.
1493 // (2) If orig_obj has not been seen yet (since start_recording_subgraph() was called),
1494 // trace all objects that are reachable from it, and make sure these objects are archived.
1495 // (3) Record the klasses of all objects that are reachable from orig_obj (including those that
1496 // were already archived when this function is called)
1497 bool HeapShared::archive_reachable_objects_from(int level,
1498 KlassSubGraphInfo* subgraph_info,
1499 oop orig_obj) {
1500 assert(orig_obj != nullptr, "must be");
1501 PendingOopStack stack;
1502 stack.push(PendingOop(orig_obj, nullptr, level));
1503
1504 while (stack.length() > 0) {
1505 PendingOop po = stack.pop();
1506 _object_being_archived = po;
1507 bool status = walk_one_object(&stack, po.level(), subgraph_info, po.obj(), po.referrer());
1508 _object_being_archived = PendingOop();
1509
1510 if (!status) {
1511 // Don't archive a subgraph root that's too big. For archives static fields, that's OK
1512 // as the Java code will take care of initializing this field dynamically.
1513 assert(level == 1, "VM should have exited with unarchivable objects for _level > 1");
1514 return false;
1515 }
1516 }
1517
1518 return true;
1519 }
1520
1521 bool HeapShared::walk_one_object(PendingOopStack* stack, int level, KlassSubGraphInfo* subgraph_info,
1522 oop orig_obj, oop referrer) {
1523 assert(orig_obj != nullptr, "must be");
1524 if (!JavaClasses::is_supported_for_archiving(orig_obj)) {
1525 // This object has injected fields that cannot be supported easily, so we disallow them for now.
1526 // If you get an error here, you probably made a change in the JDK library that has added
1527 // these objects that are referenced (directly or indirectly) by static fields.
1528 ResourceMark rm;
1529 log_error(aot, heap)("Cannot archive object " PTR_FORMAT " of class %s", p2i(orig_obj), orig_obj->klass()->external_name());
1530 debug_trace();
1531 MetaspaceShared::unrecoverable_writing_error();
1532 }
1533
1534 if (log_is_enabled(Debug, aot, heap) && java_lang_Class::is_instance(orig_obj)) {
1535 ResourceMark rm;
1536 LogTarget(Debug, aot, heap) log;
1537 LogStream out(log);
1538 out.print("Found java mirror " PTR_FORMAT " ", p2i(orig_obj));
1539 Klass* k = java_lang_Class::as_Klass(orig_obj);
1540 if (k != nullptr) {
1541 out.print("%s", k->external_name());
1542 } else {
1543 out.print("primitive");
1544 }
1545 out.print_cr("; scratch mirror = " PTR_FORMAT,
1546 p2i(scratch_java_mirror(orig_obj)));
1547 }
1548
1549 if (java_lang_Class::is_instance(orig_obj)) {
1550 Klass* k = java_lang_Class::as_Klass(orig_obj);
1551 if (RegeneratedClasses::has_been_regenerated(k)) {
1552 orig_obj = RegeneratedClasses::get_regenerated_object(k)->java_mirror();
1553 }
1554 }
1555
1556 if (CDSConfig::is_initing_classes_at_dump_time()) {
1557 if (java_lang_Class::is_instance(orig_obj)) {
1558 orig_obj = scratch_java_mirror(orig_obj);
1559 assert(orig_obj != nullptr, "must be archived");
1560 }
1561 } else if (java_lang_Class::is_instance(orig_obj) && subgraph_info != _dump_time_special_subgraph) {
1562 // Without CDSConfig::is_initing_classes_at_dump_time(), we only allow archived objects to
1563 // point to the mirrors of (1) j.l.Object, (2) primitive classes, and (3) box classes. These are initialized
1564 // very early by HeapShared::init_box_classes().
1565 if (orig_obj == vmClasses::Object_klass()->java_mirror()
1566 || java_lang_Class::is_primitive(orig_obj)
1567 || orig_obj == vmClasses::Boolean_klass()->java_mirror()
1568 || orig_obj == vmClasses::Character_klass()->java_mirror()
1569 || orig_obj == vmClasses::Float_klass()->java_mirror()
1570 || orig_obj == vmClasses::Double_klass()->java_mirror()
1571 || orig_obj == vmClasses::Byte_klass()->java_mirror()
1572 || orig_obj == vmClasses::Short_klass()->java_mirror()
1573 || orig_obj == vmClasses::Integer_klass()->java_mirror()
1574 || orig_obj == vmClasses::Long_klass()->java_mirror()
1575 || orig_obj == vmClasses::Void_klass()->java_mirror()) {
1576 orig_obj = scratch_java_mirror(orig_obj);
1577 assert(orig_obj != nullptr, "must be archived");
1578 } else {
1579 // If you get an error here, you probably made a change in the JDK library that has added a Class
1580 // object that is referenced (directly or indirectly) by an ArchivableStaticFieldInfo
1581 // defined at the top of this file.
1582 log_error(aot, heap)("(%d) Unknown java.lang.Class object is in the archived sub-graph", level);
1583 debug_trace();
1584 MetaspaceShared::unrecoverable_writing_error();
1585 }
1586 }
1587
1588 if (has_been_seen_during_subgraph_recording(orig_obj)) {
1589 // orig_obj has already been archived and traced. Nothing more to do.
1590 return true;
1591 } else {
1592 set_has_been_seen_during_subgraph_recording(orig_obj);
1593 }
1594
1595 bool already_archived = has_been_archived(orig_obj);
1596 bool record_klasses_only = already_archived;
1597 if (!already_archived) {
1598 ++_num_new_archived_objs;
1599 if (!archive_object(orig_obj, referrer, subgraph_info)) {
1600 // Skip archiving the sub-graph referenced from the current entry field.
1601 ResourceMark rm;
1602 log_error(aot, heap)(
1603 "Cannot archive the sub-graph referenced from %s object ("
1604 PTR_FORMAT ") size %zu, skipped.",
1605 orig_obj->klass()->external_name(), p2i(orig_obj), orig_obj->size() * HeapWordSize);
1606 if (level == 1) {
1607 // Don't archive a subgraph root that's too big. For archives static fields, that's OK
1608 // as the Java code will take care of initializing this field dynamically.
1609 return false;
1610 } else {
1611 // We don't know how to handle an object that has been archived, but some of its reachable
1612 // objects cannot be archived. Bail out for now. We might need to fix this in the future if
1613 // we have a real use case.
1614 MetaspaceShared::unrecoverable_writing_error();
1615 }
1616 }
1617 }
1618
1619 Klass *orig_k = orig_obj->klass();
1620 subgraph_info->add_subgraph_object_klass(orig_k);
1621
1622 {
1623 // Find all the oops that are referenced by orig_obj, push them onto the stack
1624 // so we can work on them next.
1625 ResourceMark rm;
1626 OopFieldPusher pusher(stack, level, record_klasses_only, subgraph_info, orig_obj);
1627 orig_obj->oop_iterate(&pusher);
1628 }
1629
1630 if (CDSConfig::is_initing_classes_at_dump_time()) {
1631 // The enum klasses are archived with aot-initialized mirror.
1632 // See AOTClassInitializer::can_archive_initialized_mirror().
1633 } else {
1634 if (CDSEnumKlass::is_enum_obj(orig_obj)) {
1635 CDSEnumKlass::handle_enum_obj(level + 1, subgraph_info, orig_obj);
1636 }
1637 }
1638
1639 return true;
1640 }
1641
1642 //
1643 // Start from the given static field in a java mirror and archive the
1644 // complete sub-graph of java heap objects that are reached directly
1645 // or indirectly from the starting object by following references.
1646 // Sub-graph archiving restrictions (current):
1647 //
1648 // - All classes of objects in the archived sub-graph (including the
1649 // entry class) must be boot class only.
1650 // - No java.lang.Class instance (java mirror) can be included inside
1651 // an archived sub-graph. Mirror can only be the sub-graph entry object.
1652 //
1653 // The Java heap object sub-graph archiving process (see OopFieldPusher):
1654 //
1655 // 1) Java object sub-graph archiving starts from a given static field
1656 // within a Class instance (java mirror). If the static field is a
1657 // reference field and points to a non-null java object, proceed to
1658 // the next step.
1659 //
1660 // 2) Archives the referenced java object. If an archived copy of the
1661 // current object already exists, updates the pointer in the archived
1662 // copy of the referencing object to point to the current archived object.
1663 // Otherwise, proceed to the next step.
1664 //
1665 // 3) Follows all references within the current java object and recursively
1666 // archive the sub-graph of objects starting from each reference.
1667 //
1668 // 4) Updates the pointer in the archived copy of referencing object to
1669 // point to the current archived object.
1670 //
1671 // 5) The Klass of the current java object is added to the list of Klasses
1672 // for loading and initializing before any object in the archived graph can
1673 // be accessed at runtime.
1674 //
1675 void HeapShared::archive_reachable_objects_from_static_field(InstanceKlass *k,
1676 const char* klass_name,
1677 int field_offset,
1678 const char* field_name) {
1679 assert(CDSConfig::is_dumping_heap(), "dump time only");
1680 assert(k->defined_by_boot_loader(), "must be boot class");
1681
1682 oop m = k->java_mirror();
1683
1684 KlassSubGraphInfo* subgraph_info = get_subgraph_info(k);
1685 oop f = m->obj_field(field_offset);
1686
1687 log_debug(aot, heap)("Start archiving from: %s::%s (" PTR_FORMAT ")", klass_name, field_name, p2i(f));
1688
1689 if (!CompressedOops::is_null(f)) {
1690 if (log_is_enabled(Trace, aot, heap)) {
1691 LogTarget(Trace, aot, heap) log;
1692 LogStream out(log);
1693 f->print_on(&out);
1694 }
1695
1696 bool success = archive_reachable_objects_from(1, subgraph_info, f);
1697 if (!success) {
1698 log_error(aot, heap)("Archiving failed %s::%s (some reachable objects cannot be archived)",
1699 klass_name, field_name);
1700 } else {
1701 // Note: the field value is not preserved in the archived mirror.
1702 // Record the field as a new subGraph entry point. The recorded
1703 // information is restored from the archive at runtime.
1704 subgraph_info->add_subgraph_entry_field(field_offset, f);
1705 log_info(aot, heap)("Archived field %s::%s => " PTR_FORMAT, klass_name, field_name, p2i(f));
1706 }
1707 } else {
1708 // The field contains null, we still need to record the entry point,
1709 // so it can be restored at runtime.
1710 subgraph_info->add_subgraph_entry_field(field_offset, nullptr);
1711 }
1712 }
1713
1714 #ifndef PRODUCT
1715 class VerifySharedOopClosure: public BasicOopIterateClosure {
1716 public:
1717 void do_oop(narrowOop *p) { VerifySharedOopClosure::do_oop_work(p); }
1718 void do_oop( oop *p) { VerifySharedOopClosure::do_oop_work(p); }
1719
1720 protected:
1721 template <class T> void do_oop_work(T *p) {
1722 oop obj = RawAccess<>::oop_load(p);
1723 if (!CompressedOops::is_null(obj)) {
1724 HeapShared::verify_reachable_objects_from(obj);
1725 }
1726 }
1727 };
1728
1729 void HeapShared::verify_subgraph_from_static_field(InstanceKlass* k, int field_offset) {
1730 assert(CDSConfig::is_dumping_heap(), "dump time only");
1731 assert(k->defined_by_boot_loader(), "must be boot class");
1732
1733 oop m = k->java_mirror();
1734 oop f = m->obj_field(field_offset);
1735 if (!CompressedOops::is_null(f)) {
1736 verify_subgraph_from(f);
1737 }
1738 }
1739
1740 void HeapShared::verify_subgraph_from(oop orig_obj) {
1741 if (!has_been_archived(orig_obj)) {
1742 // It's OK for the root of a subgraph to be not archived. See comments in
1743 // archive_reachable_objects_from().
1744 return;
1745 }
1746
1747 // Verify that all objects reachable from orig_obj are archived.
1748 init_seen_objects_table();
1749 verify_reachable_objects_from(orig_obj);
1750 delete_seen_objects_table();
1751 }
1752
1753 void HeapShared::verify_reachable_objects_from(oop obj) {
1754 _num_total_verifications ++;
1755 if (java_lang_Class::is_instance(obj)) {
1756 obj = scratch_java_mirror(obj);
1757 assert(obj != nullptr, "must be");
1758 }
1759 if (!has_been_seen_during_subgraph_recording(obj)) {
1760 set_has_been_seen_during_subgraph_recording(obj);
1761 assert(has_been_archived(obj), "must be");
1762 VerifySharedOopClosure walker;
1763 obj->oop_iterate(&walker);
1764 }
1765 }
1766 #endif
1767
1768 void HeapShared::check_special_subgraph_classes() {
1769 if (CDSConfig::is_initing_classes_at_dump_time()) {
1770 // We can have aot-initialized classes (such as Enums) that can reference objects
1771 // of arbitrary types. Currently, we trust the JEP 483 implementation to only
1772 // aot-initialize classes that are "safe".
1773 //
1774 // TODO: we need an automatic tool that checks the safety of aot-initialized
1775 // classes (when we extend the set of aot-initialized classes beyond JEP 483)
1776 return;
1777 } else {
1778 // In this case, the special subgraph should contain a few specific types
1779 GrowableArray<Klass*>* klasses = _dump_time_special_subgraph->subgraph_object_klasses();
1780 int num = klasses->length();
1781 for (int i = 0; i < num; i++) {
1782 Klass* subgraph_k = klasses->at(i);
1783 Symbol* name = subgraph_k->name();
1784 if (subgraph_k->is_instance_klass() &&
1785 name != vmSymbols::java_lang_Class() &&
1786 name != vmSymbols::java_lang_String() &&
1787 name != vmSymbols::java_lang_ArithmeticException() &&
1788 name != vmSymbols::java_lang_ArrayIndexOutOfBoundsException() &&
1789 name != vmSymbols::java_lang_ArrayStoreException() &&
1790 name != vmSymbols::java_lang_ClassCastException() &&
1791 name != vmSymbols::java_lang_InternalError() &&
1792 name != vmSymbols::java_lang_NullPointerException()) {
1793 ResourceMark rm;
1794 fatal("special subgraph cannot have objects of type %s", subgraph_k->external_name());
1795 }
1796 }
1797 }
1798 }
1799
1800 HeapShared::SeenObjectsTable* HeapShared::_seen_objects_table = nullptr;
1801 HeapShared::PendingOop HeapShared::_object_being_archived;
1802 int HeapShared::_num_new_walked_objs;
1803 int HeapShared::_num_new_archived_objs;
1804 int HeapShared::_num_old_recorded_klasses;
1805
1806 int HeapShared::_num_total_subgraph_recordings = 0;
1807 int HeapShared::_num_total_walked_objs = 0;
1808 int HeapShared::_num_total_archived_objs = 0;
1809 int HeapShared::_num_total_recorded_klasses = 0;
1810 int HeapShared::_num_total_verifications = 0;
1811
1812 bool HeapShared::has_been_seen_during_subgraph_recording(oop obj) {
1813 return _seen_objects_table->get(obj) != nullptr;
1814 }
1815
1816 void HeapShared::set_has_been_seen_during_subgraph_recording(oop obj) {
1817 assert(!has_been_seen_during_subgraph_recording(obj), "sanity");
1818 _seen_objects_table->put_when_absent(obj, true);
1819 _seen_objects_table->maybe_grow();
1820 ++ _num_new_walked_objs;
1821 }
1822
1823 void HeapShared::start_recording_subgraph(InstanceKlass *k, const char* class_name, bool is_full_module_graph) {
1824 log_info(aot, heap)("Start recording subgraph(s) for archived fields in %s", class_name);
1825 init_subgraph_info(k, is_full_module_graph);
1826 init_seen_objects_table();
1827 _num_new_walked_objs = 0;
1828 _num_new_archived_objs = 0;
1829 _num_old_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses();
1830 }
1831
1832 void HeapShared::done_recording_subgraph(InstanceKlass *k, const char* class_name) {
1833 int num_new_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses() -
1834 _num_old_recorded_klasses;
1835 log_info(aot, heap)("Done recording subgraph(s) for archived fields in %s: "
1836 "walked %d objs, archived %d new objs, recorded %d classes",
1837 class_name, _num_new_walked_objs, _num_new_archived_objs,
1838 num_new_recorded_klasses);
1839
1840 delete_seen_objects_table();
1841
1842 _num_total_subgraph_recordings ++;
1843 _num_total_walked_objs += _num_new_walked_objs;
1844 _num_total_archived_objs += _num_new_archived_objs;
1845 _num_total_recorded_klasses += num_new_recorded_klasses;
1846 }
1847
1848 class ArchivableStaticFieldFinder: public FieldClosure {
1849 InstanceKlass* _ik;
1850 Symbol* _field_name;
1851 bool _found;
1852 int _offset;
1853 public:
1854 ArchivableStaticFieldFinder(InstanceKlass* ik, Symbol* field_name) :
1855 _ik(ik), _field_name(field_name), _found(false), _offset(-1) {}
1856
1857 virtual void do_field(fieldDescriptor* fd) {
1858 if (fd->name() == _field_name) {
1859 assert(!_found, "fields can never be overloaded");
1860 if (is_reference_type(fd->field_type())) {
1861 _found = true;
1862 _offset = fd->offset();
1863 }
1864 }
1865 }
1866 bool found() { return _found; }
1867 int offset() { return _offset; }
1868 };
1869
1870 void HeapShared::init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[],
1871 TRAPS) {
1872 for (int i = 0; fields[i].valid(); i++) {
1873 ArchivableStaticFieldInfo* info = &fields[i];
1874 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
1875 TempNewSymbol field_name = SymbolTable::new_symbol(info->field_name);
1876 ResourceMark rm; // for stringStream::as_string() etc.
1877
1878 #ifndef PRODUCT
1879 bool is_test_class = (ArchiveHeapTestClass != nullptr) && (strcmp(info->klass_name, ArchiveHeapTestClass) == 0);
1880 const char* test_class_name = ArchiveHeapTestClass;
1881 #else
1882 bool is_test_class = false;
1883 const char* test_class_name = ""; // avoid C++ printf checks warnings.
1884 #endif
1885
1886 if (is_test_class) {
1887 log_warning(aot)("Loading ArchiveHeapTestClass %s ...", test_class_name);
1888 }
1889
1890 Klass* k = SystemDictionary::resolve_or_fail(klass_name, true, THREAD);
1891 if (HAS_PENDING_EXCEPTION) {
1892 CLEAR_PENDING_EXCEPTION;
1893 stringStream st;
1894 st.print("Fail to initialize archive heap: %s cannot be loaded by the boot loader", info->klass_name);
1895 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1896 }
1897
1898 if (!k->is_instance_klass()) {
1899 stringStream st;
1900 st.print("Fail to initialize archive heap: %s is not an instance class", info->klass_name);
1901 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1902 }
1903
1904 InstanceKlass* ik = InstanceKlass::cast(k);
1905 assert(InstanceKlass::cast(ik)->defined_by_boot_loader(),
1906 "Only support boot classes");
1907
1908 if (is_test_class) {
1909 if (ik->module()->is_named()) {
1910 // We don't want ArchiveHeapTestClass to be abused to easily load/initialize arbitrary
1911 // core-lib classes. You need to at least append to the bootclasspath.
1912 stringStream st;
1913 st.print("ArchiveHeapTestClass %s is not in unnamed module", test_class_name);
1914 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1915 }
1916
1917 if (ik->package() != nullptr) {
1918 // This restriction makes HeapShared::is_a_test_class_in_unnamed_module() easy.
1919 stringStream st;
1920 st.print("ArchiveHeapTestClass %s is not in unnamed package", test_class_name);
1921 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1922 }
1923 } else {
1924 if (ik->module()->name() != vmSymbols::java_base()) {
1925 // We don't want to deal with cases when a module is unavailable at runtime.
1926 // FUTURE -- load from archived heap only when module graph has not changed
1927 // between dump and runtime.
1928 stringStream st;
1929 st.print("%s is not in java.base module", info->klass_name);
1930 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1931 }
1932 }
1933
1934 if (is_test_class) {
1935 log_warning(aot)("Initializing ArchiveHeapTestClass %s ...", test_class_name);
1936 }
1937 ik->initialize(CHECK);
1938
1939 ArchivableStaticFieldFinder finder(ik, field_name);
1940 ik->do_local_static_fields(&finder);
1941 if (!finder.found()) {
1942 stringStream st;
1943 st.print("Unable to find the static T_OBJECT field %s::%s", info->klass_name, info->field_name);
1944 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1945 }
1946
1947 info->klass = ik;
1948 info->offset = finder.offset();
1949 }
1950 }
1951
1952 void HeapShared::init_subgraph_entry_fields(TRAPS) {
1953 assert(CDSConfig::is_dumping_heap(), "must be");
1954 _dump_time_subgraph_info_table = new (mtClass)DumpTimeKlassSubGraphInfoTable();
1955 init_subgraph_entry_fields(archive_subgraph_entry_fields, CHECK);
1956 if (CDSConfig::is_dumping_full_module_graph()) {
1957 init_subgraph_entry_fields(fmg_archive_subgraph_entry_fields, CHECK);
1958 }
1959 }
1960
1961 #ifndef PRODUCT
1962 void HeapShared::setup_test_class(const char* test_class_name) {
1963 ArchivableStaticFieldInfo* p = archive_subgraph_entry_fields;
1964 int num_slots = sizeof(archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo);
1965 assert(p[num_slots - 2].klass_name == nullptr, "must have empty slot that's patched below");
1966 assert(p[num_slots - 1].klass_name == nullptr, "must have empty slot that marks the end of the list");
1967
1968 if (test_class_name != nullptr) {
1969 p[num_slots - 2].klass_name = test_class_name;
1970 p[num_slots - 2].field_name = ARCHIVE_TEST_FIELD_NAME;
1971 }
1972 }
1973
1974 // See if ik is one of the test classes that are pulled in by -XX:ArchiveHeapTestClass
1975 // during runtime. This may be called before the module system is initialized so
1976 // we cannot rely on InstanceKlass::module(), etc.
1977 bool HeapShared::is_a_test_class_in_unnamed_module(Klass* ik) {
1978 if (_test_class != nullptr) {
1979 if (ik == _test_class) {
1980 return true;
1981 }
1982 Array<Klass*>* klasses = _test_class_record->subgraph_object_klasses();
1983 if (klasses == nullptr) {
1984 return false;
1985 }
1986
1987 for (int i = 0; i < klasses->length(); i++) {
1988 Klass* k = klasses->at(i);
1989 if (k == ik) {
1990 Symbol* name;
1991 if (k->is_instance_klass()) {
1992 name = InstanceKlass::cast(k)->name();
1993 } else if (k->is_objArray_klass()) {
1994 Klass* bk = ObjArrayKlass::cast(k)->bottom_klass();
1995 if (!bk->is_instance_klass()) {
1996 return false;
1997 }
1998 name = bk->name();
1999 } else {
2000 return false;
2001 }
2002
2003 // See KlassSubGraphInfo::check_allowed_klass() - we only allow test classes
2004 // to be:
2005 // (A) java.base classes (which must not be in the unnamed module)
2006 // (B) test classes which must be in the unnamed package of the unnamed module.
2007 // So if we see a '/' character in the class name, it must be in (A);
2008 // otherwise it must be in (B).
2009 if (name->index_of_at(0, "/", 1) >= 0) {
2010 return false; // (A)
2011 }
2012
2013 return true; // (B)
2014 }
2015 }
2016 }
2017
2018 return false;
2019 }
2020
2021 void HeapShared::initialize_test_class_from_archive(JavaThread* current) {
2022 Klass* k = _test_class;
2023 if (k != nullptr && ArchiveHeapLoader::is_in_use()) {
2024 JavaThread* THREAD = current;
2025 ExceptionMark em(THREAD);
2026 const ArchivedKlassSubGraphInfoRecord* record =
2027 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD);
2028
2029 // The _test_class is in the unnamed module, so it can't call CDS.initializeFromArchive()
2030 // from its <clinit> method. So we set up its "archivedObjects" field first, before
2031 // calling its <clinit>. This is not strictly clean, but it's a convenient way to write unit
2032 // test cases (see test/hotspot/jtreg/runtime/cds/appcds/cacheObject/ArchiveHeapTestClass.java).
2033 if (record != nullptr) {
2034 init_archived_fields_for(k, record);
2035 }
2036 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD);
2037 }
2038 }
2039 #endif
2040
2041 void HeapShared::init_for_dumping(TRAPS) {
2042 if (CDSConfig::is_dumping_heap()) {
2043 setup_test_class(ArchiveHeapTestClass);
2044 _dumped_interned_strings = new (mtClass)DumpedInternedStrings(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
2045 init_subgraph_entry_fields(CHECK);
2046 }
2047 }
2048
2049 void HeapShared::archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
2050 bool is_full_module_graph) {
2051 _num_total_subgraph_recordings = 0;
2052 _num_total_walked_objs = 0;
2053 _num_total_archived_objs = 0;
2054 _num_total_recorded_klasses = 0;
2055 _num_total_verifications = 0;
2056
2057 // For each class X that has one or more archived fields:
2058 // [1] Dump the subgraph of each archived field
2059 // [2] Create a list of all the class of the objects that can be reached
2060 // by any of these static fields.
2061 // At runtime, these classes are initialized before X's archived fields
2062 // are restored by HeapShared::initialize_from_archived_subgraph().
2063 for (int i = 0; fields[i].valid(); ) {
2064 ArchivableStaticFieldInfo* info = &fields[i];
2065 const char* klass_name = info->klass_name;
2066 start_recording_subgraph(info->klass, klass_name, is_full_module_graph);
2067
2068 // If you have specified consecutive fields of the same klass in
2069 // fields[], these will be archived in the same
2070 // {start_recording_subgraph ... done_recording_subgraph} pass to
2071 // save time.
2072 for (; fields[i].valid(); i++) {
2073 ArchivableStaticFieldInfo* f = &fields[i];
2074 if (f->klass_name != klass_name) {
2075 break;
2076 }
2077
2078 archive_reachable_objects_from_static_field(f->klass, f->klass_name,
2079 f->offset, f->field_name);
2080 }
2081 done_recording_subgraph(info->klass, klass_name);
2082 }
2083
2084 log_info(aot, heap)("Archived subgraph records = %d",
2085 _num_total_subgraph_recordings);
2086 log_info(aot, heap)(" Walked %d objects", _num_total_walked_objs);
2087 log_info(aot, heap)(" Archived %d objects", _num_total_archived_objs);
2088 log_info(aot, heap)(" Recorded %d klasses", _num_total_recorded_klasses);
2089
2090 #ifndef PRODUCT
2091 for (int i = 0; fields[i].valid(); i++) {
2092 ArchivableStaticFieldInfo* f = &fields[i];
2093 verify_subgraph_from_static_field(f->klass, f->offset);
2094 }
2095 log_info(aot, heap)(" Verified %d references", _num_total_verifications);
2096 #endif
2097 }
2098
2099 // Keep track of the contents of the archived interned string table. This table
2100 // is used only by CDSHeapVerifier.
2101 void HeapShared::add_to_dumped_interned_strings(oop string) {
2102 assert_at_safepoint(); // DumpedInternedStrings uses raw oops
2103 assert(!ArchiveHeapWriter::is_string_too_large_to_archive(string), "must be");
2104 bool created;
2105 _dumped_interned_strings->put_if_absent(string, true, &created);
2106 if (created) {
2107 // Prevent string deduplication from changing the value field to
2108 // something not in the archive.
2109 java_lang_String::set_deduplication_forbidden(string);
2110 _dumped_interned_strings->maybe_grow();
2111 }
2112 }
2113
2114 bool HeapShared::is_dumped_interned_string(oop o) {
2115 return _dumped_interned_strings->get(o) != nullptr;
2116 }
2117
2118 void HeapShared::debug_trace() {
2119 ResourceMark rm;
2120 oop referrer = _object_being_archived.referrer();
2121 if (referrer != nullptr) {
2122 LogStream ls(Log(aot, heap)::error());
2123 ls.print_cr("Reference trace");
2124 CDSHeapVerifier::trace_to_root(&ls, referrer);
2125 }
2126 }
2127
2128 #ifndef PRODUCT
2129 // At dump-time, find the location of all the non-null oop pointers in an archived heap
2130 // region. This way we can quickly relocate all the pointers without using
2131 // BasicOopIterateClosure at runtime.
2132 class FindEmbeddedNonNullPointers: public BasicOopIterateClosure {
2133 void* _start;
2134 BitMap *_oopmap;
2135 int _num_total_oops;
2136 int _num_null_oops;
2137 public:
2138 FindEmbeddedNonNullPointers(void* start, BitMap* oopmap)
2139 : _start(start), _oopmap(oopmap), _num_total_oops(0), _num_null_oops(0) {}
2140
2141 virtual void do_oop(narrowOop* p) {
2142 assert(UseCompressedOops, "sanity");
2143 _num_total_oops ++;
2144 narrowOop v = *p;
2145 if (!CompressedOops::is_null(v)) {
2146 size_t idx = p - (narrowOop*)_start;
2147 _oopmap->set_bit(idx);
2148 } else {
2149 _num_null_oops ++;
2150 }
2151 }
2152 virtual void do_oop(oop* p) {
2153 assert(!UseCompressedOops, "sanity");
2154 _num_total_oops ++;
2155 if ((*p) != nullptr) {
2156 size_t idx = p - (oop*)_start;
2157 _oopmap->set_bit(idx);
2158 } else {
2159 _num_null_oops ++;
2160 }
2161 }
2162 int num_total_oops() const { return _num_total_oops; }
2163 int num_null_oops() const { return _num_null_oops; }
2164 };
2165 #endif
2166
2167 void HeapShared::count_allocation(size_t size) {
2168 _total_obj_count ++;
2169 _total_obj_size += size;
2170 for (int i = 0; i < ALLOC_STAT_SLOTS; i++) {
2171 if (size <= (size_t(1) << i)) {
2172 _alloc_count[i] ++;
2173 _alloc_size[i] += size;
2174 return;
2175 }
2176 }
2177 }
2178
2179 static double avg_size(size_t size, size_t count) {
2180 double avg = 0;
2181 if (count > 0) {
2182 avg = double(size * HeapWordSize) / double(count);
2183 }
2184 return avg;
2185 }
2186
2187 void HeapShared::print_stats() {
2188 size_t huge_count = _total_obj_count;
2189 size_t huge_size = _total_obj_size;
2190
2191 for (int i = 0; i < ALLOC_STAT_SLOTS; i++) {
2192 size_t byte_size_limit = (size_t(1) << i) * HeapWordSize;
2193 size_t count = _alloc_count[i];
2194 size_t size = _alloc_size[i];
2195 log_info(aot, heap)("%8zu objects are <= %-6zu"
2196 " bytes (total %8zu bytes, avg %8.1f bytes)",
2197 count, byte_size_limit, size * HeapWordSize, avg_size(size, count));
2198 huge_count -= count;
2199 huge_size -= size;
2200 }
2201
2202 log_info(aot, heap)("%8zu huge objects (total %8zu bytes"
2203 ", avg %8.1f bytes)",
2204 huge_count, huge_size * HeapWordSize,
2205 avg_size(huge_size, huge_count));
2206 log_info(aot, heap)("%8zu total objects (total %8zu bytes"
2207 ", avg %8.1f bytes)",
2208 _total_obj_count, _total_obj_size * HeapWordSize,
2209 avg_size(_total_obj_size, _total_obj_count));
2210 }
2211
2212 bool HeapShared::is_archived_boot_layer_available(JavaThread* current) {
2213 TempNewSymbol klass_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_CLASS);
2214 InstanceKlass* k = SystemDictionary::find_instance_klass(current, klass_name, Handle());
2215 if (k == nullptr) {
2216 return false;
2217 } else {
2218 TempNewSymbol field_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_FIELD);
2219 TempNewSymbol field_signature = SymbolTable::new_symbol("Ljdk/internal/module/ArchivedBootLayer;");
2220 fieldDescriptor fd;
2221 if (k->find_field(field_name, field_signature, true, &fd) != nullptr) {
2222 oop m = k->java_mirror();
2223 oop f = m->obj_field(fd.offset());
2224 if (CompressedOops::is_null(f)) {
2225 return false;
2226 }
2227 } else {
2228 return false;
2229 }
2230 }
2231 return true;
2232 }
2233
2234 #endif // INCLUDE_CDS_JAVA_HEAP