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 "cds/archiveUtils.hpp"
27 #include "cds/classListWriter.hpp"
28 #include "cds/heapShared.hpp"
29 #include "cds/metaspaceShared.hpp"
30 #include "classfile/classFileParser.hpp"
31 #include "classfile/classFileStream.hpp"
32 #include "classfile/classLoader.hpp"
33 #include "classfile/classLoaderData.inline.hpp"
34 #include "classfile/javaClasses.hpp"
35 #include "classfile/moduleEntry.hpp"
36 #include "classfile/systemDictionary.hpp"
37 #include "classfile/systemDictionaryShared.hpp"
38 #include "classfile/verifier.hpp"
39 #include "classfile/vmClasses.hpp"
40 #include "classfile/vmSymbols.hpp"
41 #include "code/codeCache.hpp"
42 #include "code/dependencyContext.hpp"
43 #include "compiler/compilationPolicy.hpp"
44 #include "compiler/compileBroker.hpp"
45 #include "gc/shared/collectedHeap.inline.hpp"
46 #include "interpreter/bytecodeStream.hpp"
47 #include "interpreter/oopMapCache.hpp"
48 #include "interpreter/rewriter.hpp"
49 #include "jvm.h"
50 #include "jvmtifiles/jvmti.h"
51 #include "logging/log.hpp"
52 #include "logging/logMessage.hpp"
53 #include "logging/logStream.hpp"
54 #include "memory/allocation.inline.hpp"
55 #include "memory/iterator.inline.hpp"
56 #include "memory/metadataFactory.hpp"
57 #include "memory/metaspaceClosure.hpp"
58 #include "memory/oopFactory.hpp"
59 #include "memory/resourceArea.hpp"
60 #include "memory/universe.hpp"
61 #include "oops/fieldStreams.inline.hpp"
62 #include "oops/constantPool.hpp"
63 #include "oops/instanceClassLoaderKlass.hpp"
64 #include "oops/instanceKlass.inline.hpp"
65 #include "oops/instanceMirrorKlass.hpp"
66 #include "oops/instanceOop.hpp"
67 #include "oops/instanceStackChunkKlass.hpp"
68 #include "oops/klass.inline.hpp"
69 #include "oops/method.hpp"
70 #include "oops/oop.inline.hpp"
71 #include "oops/recordComponent.hpp"
72 #include "oops/symbol.hpp"
73 #include "oops/inlineKlass.hpp"
74 #include "prims/jvmtiExport.hpp"
75 #include "prims/jvmtiRedefineClasses.hpp"
76 #include "prims/jvmtiThreadState.hpp"
77 #include "prims/methodComparator.hpp"
78 #include "runtime/arguments.hpp"
79 #include "runtime/deoptimization.hpp"
80 #include "runtime/atomic.hpp"
81 #include "runtime/fieldDescriptor.inline.hpp"
82 #include "runtime/handles.inline.hpp"
83 #include "runtime/javaCalls.hpp"
84 #include "runtime/javaThread.inline.hpp"
85 #include "runtime/mutexLocker.hpp"
86 #include "runtime/orderAccess.hpp"
87 #include "runtime/os.inline.hpp"
88 #include "runtime/reflectionUtils.hpp"
89 #include "runtime/threads.hpp"
90 #include "services/classLoadingService.hpp"
91 #include "services/finalizerService.hpp"
92 #include "services/threadService.hpp"
93 #include "utilities/dtrace.hpp"
94 #include "utilities/events.hpp"
95 #include "utilities/macros.hpp"
96 #include "utilities/stringUtils.hpp"
97 #include "utilities/pair.hpp"
98 #ifdef COMPILER1
99 #include "c1/c1_Compiler.hpp"
100 #endif
101 #if INCLUDE_JFR
102 #include "jfr/jfrEvents.hpp"
103 #endif
104
105 #ifdef DTRACE_ENABLED
106
107
108 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
109 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
110 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
111 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
112 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
113 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
114 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
115 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
116 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
117 { \
118 char* data = nullptr; \
119 int len = 0; \
120 Symbol* clss_name = name(); \
121 if (clss_name != nullptr) { \
122 data = (char*)clss_name->bytes(); \
123 len = clss_name->utf8_length(); \
124 } \
125 HOTSPOT_CLASS_INITIALIZATION_##type( \
126 data, len, (void*)class_loader(), thread_type); \
127 }
128
129 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
130 { \
131 char* data = nullptr; \
132 int len = 0; \
133 Symbol* clss_name = name(); \
134 if (clss_name != nullptr) { \
135 data = (char*)clss_name->bytes(); \
136 len = clss_name->utf8_length(); \
137 } \
138 HOTSPOT_CLASS_INITIALIZATION_##type( \
139 data, len, (void*)class_loader(), thread_type, wait); \
140 }
141
142 #else // ndef DTRACE_ENABLED
143
144 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
145 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
146
147 #endif // ndef DTRACE_ENABLED
148
149 bool InstanceKlass::_finalization_enabled = true;
150
151 static inline bool is_class_loader(const Symbol* class_name,
152 const ClassFileParser& parser) {
153 assert(class_name != nullptr, "invariant");
154
155 if (class_name == vmSymbols::java_lang_ClassLoader()) {
156 return true;
157 }
158
159 if (vmClasses::ClassLoader_klass_loaded()) {
160 const Klass* const super_klass = parser.super_klass();
161 if (super_klass != nullptr) {
162 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
163 return true;
164 }
165 }
166 }
167 return false;
168 }
169
170 bool InstanceKlass::field_is_null_free_inline_type(int index) const {
171 return field(index).field_flags().is_null_free_inline_type();
172 }
173
174 static inline bool is_stack_chunk_class(const Symbol* class_name,
175 const ClassLoaderData* loader_data) {
176 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
177 loader_data->is_the_null_class_loader_data());
178 }
179
180 // private: called to verify that k is a static member of this nest.
181 // We know that k is an instance class in the same package and hence the
182 // same classloader.
183 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
184 assert(!is_hidden(), "unexpected hidden class");
185 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
186 if (log_is_enabled(Trace, class, nestmates)) {
187 ResourceMark rm(current);
188 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
189 k->external_name(), this->external_name());
190 }
191 return false;
192 }
193
194 if (log_is_enabled(Trace, class, nestmates)) {
195 ResourceMark rm(current);
196 log_trace(class, nestmates)("Checking nest membership of %s in %s",
197 k->external_name(), this->external_name());
198 }
199
200 // Check for the named class in _nest_members.
201 // We don't resolve, or load, any classes.
202 for (int i = 0; i < _nest_members->length(); i++) {
203 int cp_index = _nest_members->at(i);
204 Symbol* name = _constants->klass_name_at(cp_index);
205 if (name == k->name()) {
206 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
207 return true;
208 }
209 }
210 log_trace(class, nestmates)("- class is NOT a nest member!");
211 return false;
212 }
213
214 // Called to verify that k is a permitted subclass of this class
215 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
216 Thread* current = Thread::current();
217 assert(k != nullptr, "sanity check");
218 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
219 "unexpected empty _permitted_subclasses array");
220
221 if (log_is_enabled(Trace, class, sealed)) {
222 ResourceMark rm(current);
223 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
224 k->external_name(), this->external_name());
225 }
226
227 // Check that the class and its super are in the same module.
228 if (k->module() != this->module()) {
229 ResourceMark rm(current);
230 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
231 k->external_name(), this->external_name());
232 return false;
233 }
234
235 if (!k->is_public() && !is_same_class_package(k)) {
236 ResourceMark rm(current);
237 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
238 k->external_name(), this->external_name());
239 return false;
240 }
241
242 for (int i = 0; i < _permitted_subclasses->length(); i++) {
243 int cp_index = _permitted_subclasses->at(i);
244 Symbol* name = _constants->klass_name_at(cp_index);
245 if (name == k->name()) {
246 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
247 return true;
248 }
249 }
250 log_trace(class, sealed)("- class is NOT a permitted subclass!");
251 return false;
252 }
253
254 // Return nest-host class, resolving, validating and saving it if needed.
255 // In cases where this is called from a thread that cannot do classloading
256 // (such as a native JIT thread) then we simply return null, which in turn
257 // causes the access check to return false. Such code will retry the access
258 // from a more suitable environment later. Otherwise the _nest_host is always
259 // set once this method returns.
260 // Any errors from nest-host resolution must be preserved so they can be queried
261 // from higher-level access checking code, and reported as part of access checking
262 // exceptions.
263 // VirtualMachineErrors are propagated with a null return.
264 // Under any conditions where the _nest_host can be set to non-null the resulting
265 // value of it and, if applicable, the nest host resolution/validation error,
266 // are idempotent.
267 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
268 InstanceKlass* nest_host_k = _nest_host;
269 if (nest_host_k != nullptr) {
270 return nest_host_k;
271 }
272
273 ResourceMark rm(THREAD);
274
275 // need to resolve and save our nest-host class.
276 if (_nest_host_index != 0) { // we have a real nest_host
277 // Before trying to resolve check if we're in a suitable context
278 bool can_resolve = THREAD->can_call_java();
279 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
280 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
281 this->external_name());
282 return nullptr; // sentinel to say "try again from a different context"
283 }
284
285 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
286 this->external_name(),
287 _constants->klass_name_at(_nest_host_index)->as_C_string());
288
289 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
290 if (HAS_PENDING_EXCEPTION) {
291 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
292 return nullptr; // propagate VMEs
293 }
294 stringStream ss;
295 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
296 ss.print("Nest host resolution of %s with host %s failed: ",
297 this->external_name(), target_host_class);
298 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
299 const char* msg = ss.as_string(true /* on C-heap */);
300 constantPoolHandle cph(THREAD, constants());
301 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
302 CLEAR_PENDING_EXCEPTION;
303
304 log_trace(class, nestmates)("%s", msg);
305 } else {
306 // A valid nest-host is an instance class in the current package that lists this
307 // class as a nest member. If any of these conditions are not met the class is
308 // its own nest-host.
309 const char* error = nullptr;
310
311 // JVMS 5.4.4 indicates package check comes first
312 if (is_same_class_package(k)) {
313 // Now check actual membership. We can't be a member if our "host" is
314 // not an instance class.
315 if (k->is_instance_klass()) {
316 nest_host_k = InstanceKlass::cast(k);
317 bool is_member = nest_host_k->has_nest_member(THREAD, this);
318 if (is_member) {
319 _nest_host = nest_host_k; // save resolved nest-host value
320
321 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
322 this->external_name(), k->external_name());
323 return nest_host_k;
324 } else {
325 error = "current type is not listed as a nest member";
326 }
327 } else {
328 error = "host is not an instance class";
329 }
330 } else {
331 error = "types are in different packages";
332 }
333
334 // something went wrong, so record what and log it
335 {
336 stringStream ss;
337 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
338 this->external_name(),
339 this->class_loader_data()->loader_name_and_id(),
340 k->external_name(),
341 k->class_loader_data()->loader_name_and_id(),
342 error);
343 const char* msg = ss.as_string(true /* on C-heap */);
344 constantPoolHandle cph(THREAD, constants());
345 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
346 log_trace(class, nestmates)("%s", msg);
347 }
348 }
349 } else {
350 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
351 this->external_name());
352 }
353
354 // Either not in an explicit nest, or else an error occurred, so
355 // the nest-host is set to `this`. Any thread that sees this assignment
356 // will also see any setting of nest_host_error(), if applicable.
357 return (_nest_host = this);
358 }
359
360 // Dynamic nest member support: set this class's nest host to the given class.
361 // This occurs as part of the class definition, as soon as the instanceKlass
362 // has been created and doesn't require further resolution. The code:
363 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
364 // results in:
365 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
366 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
367 // We also know the "host" is a valid nest-host in the same package so we can
368 // assert some of those facts.
369 void InstanceKlass::set_nest_host(InstanceKlass* host) {
370 assert(is_hidden(), "must be a hidden class");
371 assert(host != nullptr, "null nest host specified");
372 assert(_nest_host == nullptr, "current class has resolved nest-host");
373 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
374 nest_host_error());
375 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
376 (host->_nest_host == host), "proposed host is not a valid nest-host");
377 // Can't assert this as package is not set yet:
378 // assert(is_same_class_package(host), "proposed host is in wrong package");
379
380 if (log_is_enabled(Trace, class, nestmates)) {
381 ResourceMark rm;
382 const char* msg = "";
383 // a hidden class does not expect a statically defined nest-host
384 if (_nest_host_index > 0) {
385 msg = "(the NestHost attribute in the current class is ignored)";
386 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
387 msg = "(the NestMembers attribute in the current class is ignored)";
388 }
389 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
390 this->external_name(),
391 host->external_name(),
392 msg);
393 }
394 // set dynamic nest host
395 _nest_host = host;
396 // Record dependency to keep nest host from being unloaded before this class.
397 ClassLoaderData* this_key = class_loader_data();
398 assert(this_key != nullptr, "sanity");
399 this_key->record_dependency(host);
400 }
401
402 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
403 // or we are k's nest_host - all of which is covered by comparing the two
404 // resolved_nest_hosts.
405 // Any exceptions (i.e. VMEs) are propagated.
406 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
407
408 assert(this != k, "this should be handled by higher-level code");
409
410 // Per JVMS 5.4.4 we first resolve and validate the current class, then
411 // the target class k.
412
413 InstanceKlass* cur_host = nest_host(CHECK_false);
414 if (cur_host == nullptr) {
415 return false;
416 }
417
418 Klass* k_nest_host = k->nest_host(CHECK_false);
419 if (k_nest_host == nullptr) {
420 return false;
421 }
422
423 bool access = (cur_host == k_nest_host);
424
425 ResourceMark rm(THREAD);
426 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
427 this->external_name(),
428 access ? "" : "NOT ",
429 k->external_name());
430 return access;
431 }
432
433 const char* InstanceKlass::nest_host_error() {
434 if (_nest_host_index == 0) {
435 return nullptr;
436 } else {
437 constantPoolHandle cph(Thread::current(), constants());
438 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
439 }
440 }
441
442 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
443 const int size = InstanceKlass::size(parser.vtable_size(),
444 parser.itable_size(),
445 nonstatic_oop_map_size(parser.total_oop_map_count()),
446 parser.is_interface(),
447 parser.has_inline_fields() ? parser.java_fields_count() : 0,
448 parser.is_inline_type());
449
450 const Symbol* const class_name = parser.class_name();
451 assert(class_name != nullptr, "invariant");
452 ClassLoaderData* loader_data = parser.loader_data();
453 assert(loader_data != nullptr, "invariant");
454
455 InstanceKlass* ik;
456
457 // Allocation
458 if (parser.is_instance_ref_klass()) {
459 // java.lang.ref.Reference
460 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
461 } else if (class_name == vmSymbols::java_lang_Class()) {
462 // mirror - java.lang.Class
463 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
464 } else if (is_stack_chunk_class(class_name, loader_data)) {
465 // stack chunk
466 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
467 } else if (is_class_loader(class_name, parser)) {
468 // class loader - java.lang.ClassLoader
469 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
470 } else if (parser.is_inline_type()) {
471 // inline type
472 ik = new (loader_data, size, THREAD) InlineKlass(parser);
473 } else {
474 // normal
475 ik = new (loader_data, size, THREAD) InstanceKlass(parser);
476 }
477
478 // Check for pending exception before adding to the loader data and incrementing
479 // class count. Can get OOM here.
480 if (HAS_PENDING_EXCEPTION) {
481 return nullptr;
482 }
483
484 #ifdef ASSERT
485 ik->bounds_check((address) ik->start_of_vtable(), false, size);
486 ik->bounds_check((address) ik->start_of_itable(), false, size);
487 ik->bounds_check((address) ik->end_of_itable(), true, size);
488 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
489 #endif //ASSERT
490 return ik;
491 }
492
493 #ifndef PRODUCT
494 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
495 const char* bad = nullptr;
496 address end = nullptr;
497 if (addr < (address)this) {
498 bad = "before";
499 } else if (addr == (address)this) {
500 if (edge_ok) return true;
501 bad = "just before";
502 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
503 if (edge_ok) return true;
504 bad = "just after";
505 } else if (addr > end) {
506 bad = "after";
507 } else {
508 return true;
509 }
510 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
511 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
512 Verbose = WizardMode = true; this->print(); //@@
513 return false;
514 }
515 #endif //PRODUCT
516
517 // copy method ordering from resource area to Metaspace
518 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
519 if (m != nullptr) {
520 // allocate a new array and copy contents (memcpy?)
521 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
522 for (int i = 0; i < m->length(); i++) {
523 _method_ordering->at_put(i, m->at(i));
524 }
525 } else {
526 _method_ordering = Universe::the_empty_int_array();
527 }
528 }
529
530 // create a new array of vtable_indices for default methods
531 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
532 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
533 assert(default_vtable_indices() == nullptr, "only create once");
534 set_default_vtable_indices(vtable_indices);
535 return vtable_indices;
536 }
537
538 static Monitor* create_init_monitor(const char* name) {
539 return new Monitor(Mutex::safepoint, name);
540 }
541
542 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
543 Klass(kind),
544 _nest_members(nullptr),
545 _nest_host(nullptr),
546 _permitted_subclasses(nullptr),
547 _record_components(nullptr),
548 _static_field_size(parser.static_field_size()),
549 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
550 _itable_len(parser.itable_size()),
551 _nest_host_index(0),
552 _init_state(allocated),
553 _reference_type(reference_type),
554 _init_monitor(create_init_monitor("InstanceKlassInitMonitor_lock")),
555 _init_thread(nullptr),
556 _inline_type_field_klasses(nullptr),
557 _preload_classes(nullptr),
558 _adr_inlineklass_fixed_block(nullptr)
559 {
560 set_vtable_length(parser.vtable_size());
561 set_access_flags(parser.access_flags());
562 if (parser.is_hidden()) set_is_hidden();
563 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
564 false));
565 if (parser.has_inline_fields()) {
566 set_has_inline_type_fields();
567 }
568
569 assert(nullptr == _methods, "underlying memory not zeroed?");
570 assert(is_instance_klass(), "is layout incorrect?");
571 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
572
573 if (has_inline_type_fields()) {
574 _inline_type_field_klasses = (const Klass**) adr_inline_type_field_klasses();
575 }
576 }
577
578 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
579 Array<Method*>* methods) {
580 if (methods != nullptr && methods != Universe::the_empty_method_array() &&
581 !methods->is_shared()) {
582 for (int i = 0; i < methods->length(); i++) {
583 Method* method = methods->at(i);
584 if (method == nullptr) continue; // maybe null if error processing
585 // Only want to delete methods that are not executing for RedefineClasses.
586 // The previous version will point to them so they're not totally dangling
587 assert (!method->on_stack(), "shouldn't be called with methods on stack");
588 MetadataFactory::free_metadata(loader_data, method);
589 }
590 MetadataFactory::free_array<Method*>(loader_data, methods);
591 }
592 }
593
594 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
595 const Klass* super_klass,
596 Array<InstanceKlass*>* local_interfaces,
597 Array<InstanceKlass*>* transitive_interfaces) {
598 // Only deallocate transitive interfaces if not empty, same as super class
599 // or same as local interfaces. See code in parseClassFile.
600 Array<InstanceKlass*>* ti = transitive_interfaces;
601 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
602 // check that the interfaces don't come from super class
603 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
604 InstanceKlass::cast(super_klass)->transitive_interfaces();
605 if (ti != sti && ti != nullptr && !ti->is_shared()) {
606 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
607 }
608 }
609
610 // local interfaces can be empty
611 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
612 local_interfaces != nullptr && !local_interfaces->is_shared()) {
613 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
614 }
615 }
616
617 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
618 Array<RecordComponent*>* record_components) {
619 if (record_components != nullptr && !record_components->is_shared()) {
620 for (int i = 0; i < record_components->length(); i++) {
621 RecordComponent* record_component = record_components->at(i);
622 MetadataFactory::free_metadata(loader_data, record_component);
623 }
624 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
625 }
626 }
627
628 // This function deallocates the metadata and C heap pointers that the
629 // InstanceKlass points to.
630 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
631 // Orphan the mirror first, CMS thinks it's still live.
632 if (java_mirror() != nullptr) {
633 java_lang_Class::set_klass(java_mirror(), nullptr);
634 }
635
636 // Also remove mirror from handles
637 loader_data->remove_handle(_java_mirror);
638
639 // Need to take this class off the class loader data list.
640 loader_data->remove_class(this);
641
642 // The array_klass for this class is created later, after error handling.
643 // For class redefinition, we keep the original class so this scratch class
644 // doesn't have an array class. Either way, assert that there is nothing
645 // to deallocate.
646 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
647
648 // Release C heap allocated data that this points to, which includes
649 // reference counting symbol names.
650 // Can't release the constant pool or MethodData C heap data here because the constant
651 // pool can be deallocated separately from the InstanceKlass for default methods and
652 // redefine classes. MethodData can also be released separately.
653 release_C_heap_structures(/* release_sub_metadata */ false);
654
655 deallocate_methods(loader_data, methods());
656 set_methods(nullptr);
657
658 deallocate_record_components(loader_data, record_components());
659 set_record_components(nullptr);
660
661 if (method_ordering() != nullptr &&
662 method_ordering() != Universe::the_empty_int_array() &&
663 !method_ordering()->is_shared()) {
664 MetadataFactory::free_array<int>(loader_data, method_ordering());
665 }
666 set_method_ordering(nullptr);
667
668 // default methods can be empty
669 if (default_methods() != nullptr &&
670 default_methods() != Universe::the_empty_method_array() &&
671 !default_methods()->is_shared()) {
672 MetadataFactory::free_array<Method*>(loader_data, default_methods());
673 }
674 // Do NOT deallocate the default methods, they are owned by superinterfaces.
675 set_default_methods(nullptr);
676
677 // default methods vtable indices can be empty
678 if (default_vtable_indices() != nullptr &&
679 !default_vtable_indices()->is_shared()) {
680 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
681 }
682 set_default_vtable_indices(nullptr);
683
684
685 // This array is in Klass, but remove it with the InstanceKlass since
686 // this place would be the only caller and it can share memory with transitive
687 // interfaces.
688 if (secondary_supers() != nullptr &&
689 secondary_supers() != Universe::the_empty_klass_array() &&
690 // see comments in compute_secondary_supers about the following cast
691 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
692 !secondary_supers()->is_shared()) {
693 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
694 }
695 set_secondary_supers(nullptr);
696
697 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
698 set_transitive_interfaces(nullptr);
699 set_local_interfaces(nullptr);
700
701 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
702 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
703 }
704 set_fieldinfo_stream(nullptr);
705
706 if (fields_status() != nullptr && !fields_status()->is_shared()) {
707 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
708 }
709 set_fields_status(nullptr);
710
711 // If a method from a redefined class is using this constant pool, don't
712 // delete it, yet. The new class's previous version will point to this.
713 if (constants() != nullptr) {
714 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
715 if (!constants()->is_shared()) {
716 MetadataFactory::free_metadata(loader_data, constants());
717 }
718 // Delete any cached resolution errors for the constant pool
719 SystemDictionary::delete_resolution_error(constants());
720
721 set_constants(nullptr);
722 }
723
724 if (inner_classes() != nullptr &&
725 inner_classes() != Universe::the_empty_short_array() &&
726 !inner_classes()->is_shared()) {
727 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
728 }
729 set_inner_classes(nullptr);
730
731 if (nest_members() != nullptr &&
732 nest_members() != Universe::the_empty_short_array() &&
733 !nest_members()->is_shared()) {
734 MetadataFactory::free_array<jushort>(loader_data, nest_members());
735 }
736 set_nest_members(nullptr);
737
738 if (permitted_subclasses() != nullptr &&
739 permitted_subclasses() != Universe::the_empty_short_array() &&
740 !permitted_subclasses()->is_shared()) {
741 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
742 }
743 set_permitted_subclasses(nullptr);
744
745 if (preload_classes() != nullptr &&
746 preload_classes() != Universe::the_empty_short_array() &&
747 !preload_classes()->is_shared()) {
748 MetadataFactory::free_array<jushort>(loader_data, preload_classes());
749 }
750
751 // We should deallocate the Annotations instance if it's not in shared spaces.
752 if (annotations() != nullptr && !annotations()->is_shared()) {
753 MetadataFactory::free_metadata(loader_data, annotations());
754 }
755 set_annotations(nullptr);
756
757 SystemDictionaryShared::handle_class_unloading(this);
758
759 #if INCLUDE_CDS_JAVA_HEAP
760 if (DumpSharedSpaces) {
761 HeapShared::remove_scratch_objects(this);
762 }
763 #endif
764 }
765
766 bool InstanceKlass::is_record() const {
767 return _record_components != nullptr &&
768 is_final() &&
769 java_super() == vmClasses::Record_klass();
770 }
771
772 bool InstanceKlass::is_sealed() const {
773 return _permitted_subclasses != nullptr &&
774 _permitted_subclasses != Universe::the_empty_short_array();
775 }
776
777 bool InstanceKlass::should_be_initialized() const {
778 return !is_initialized();
779 }
780
781 klassItable InstanceKlass::itable() const {
782 return klassItable(const_cast<InstanceKlass*>(this));
783 }
784
785 // JVMTI spec thinks there are signers and protection domain in the
786 // instanceKlass. These accessors pretend these fields are there.
787 // The hprof specification also thinks these fields are in InstanceKlass.
788 oop InstanceKlass::protection_domain() const {
789 // return the protection_domain from the mirror
790 return java_lang_Class::protection_domain(java_mirror());
791 }
792
793 objArrayOop InstanceKlass::signers() const {
794 // return the signers from the mirror
795 return java_lang_Class::signers(java_mirror());
796 }
797
798 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
799 // process. The step comments refers to the procedure described in that section.
800 // Note: implementation moved to static method to expose the this pointer.
801 void InstanceKlass::initialize(TRAPS) {
802 if (this->should_be_initialized()) {
803 initialize_impl(CHECK);
804 // Note: at this point the class may be initialized
805 // OR it may be in the state of being initialized
806 // in case of recursive initialization!
807 } else {
808 assert(is_initialized(), "sanity check");
809 }
810 }
811
812
813 bool InstanceKlass::verify_code(TRAPS) {
814 // 1) Verify the bytecodes
815 return Verifier::verify(this, should_verify_class(), THREAD);
816 }
817
818 void InstanceKlass::link_class(TRAPS) {
819 assert(is_loaded(), "must be loaded");
820 if (!is_linked()) {
821 link_class_impl(CHECK);
822 }
823 }
824
825 void InstanceKlass::check_link_state_and_wait(JavaThread* current) {
826 MonitorLocker ml(current, _init_monitor);
827
828 // Another thread is linking this class, wait.
829 while (is_being_linked() && !is_init_thread(current)) {
830 ml.wait();
831 }
832
833 // This thread is recursively linking this class, continue
834 if (is_being_linked() && is_init_thread(current)) {
835 return;
836 }
837
838 // If this class wasn't linked already, set state to being_linked
839 if (!is_linked()) {
840 set_init_state(being_linked);
841 set_init_thread(current);
842 }
843 }
844
845 // Called to verify that a class can link during initialization, without
846 // throwing a VerifyError.
847 bool InstanceKlass::link_class_or_fail(TRAPS) {
848 assert(is_loaded(), "must be loaded");
849 if (!is_linked()) {
850 link_class_impl(CHECK_false);
851 }
852 return is_linked();
853 }
854
855 bool InstanceKlass::link_class_impl(TRAPS) {
856 if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) {
857 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
858 // the class has failed verification. Throwing the NoClassDefFoundError here is just
859 // a convenient way to stop repeat attempts to verify the same (bad) class.
860 //
861 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
862 // if we are executing Java code. This is not a problem for CDS dumping phase since
863 // it doesn't execute any Java code.
864 ResourceMark rm(THREAD);
865 Exceptions::fthrow(THREAD_AND_LOCATION,
866 vmSymbols::java_lang_NoClassDefFoundError(),
867 "Class %s, or one of its supertypes, failed class initialization",
868 external_name());
869 return false;
870 }
871 // return if already verified
872 if (is_linked()) {
873 return true;
874 }
875
876 // Timing
877 // timer handles recursion
878 JavaThread* jt = THREAD;
879
880 // link super class before linking this class
881 Klass* super_klass = super();
882 if (super_klass != nullptr) {
883 if (super_klass->is_interface()) { // check if super class is an interface
884 ResourceMark rm(THREAD);
885 Exceptions::fthrow(
886 THREAD_AND_LOCATION,
887 vmSymbols::java_lang_IncompatibleClassChangeError(),
888 "class %s has interface %s as super class",
889 external_name(),
890 super_klass->external_name()
891 );
892 return false;
893 }
894
895 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
896 ik_super->link_class_impl(CHECK_false);
897 }
898
899 // link all interfaces implemented by this class before linking this class
900 Array<InstanceKlass*>* interfaces = local_interfaces();
901 int num_interfaces = interfaces->length();
902 for (int index = 0; index < num_interfaces; index++) {
903 InstanceKlass* interk = interfaces->at(index);
904 interk->link_class_impl(CHECK_false);
905 }
906
907
908 // If a class declares a method that uses an inline class as an argument
909 // type or return inline type, this inline class must be loaded during the
910 // linking of this class because size and properties of the inline class
911 // must be known in order to be able to perform inline type optimizations.
912 // The implementation below is an approximation of this rule, the code
913 // iterates over all methods of the current class (including overridden
914 // methods), not only the methods declared by this class. This
915 // approximation makes the code simpler, and doesn't change the semantic
916 // because classes declaring methods overridden by the current class are
917 // linked (and have performed their own pre-loading) before the linking
918 // of the current class.
919
920
921 // Note:
922 // Inline class types are loaded during
923 // the loading phase (see ClassFileParser::post_process_parsed_stream()).
924 // Inline class types used as element types for array creation
925 // are not pre-loaded. Their loading is triggered by either anewarray
926 // or multianewarray bytecodes.
927
928 // Could it be possible to do the following processing only if the
929 // class uses inline types?
930 if (EnableValhalla) {
931 ResourceMark rm(THREAD);
932 if (EnablePrimitiveClasses) {
933 for (int i = 0; i < methods()->length(); i++) {
934 Method* m = methods()->at(i);
935 for (SignatureStream ss(m->signature()); !ss.is_done(); ss.next()) {
936 if (ss.is_reference()) {
937 if (ss.is_array()) {
938 continue;
939 }
940 if (ss.type() == T_PRIMITIVE_OBJECT) {
941 Symbol* symb = ss.as_symbol();
942 if (symb == name()) continue;
943 oop loader = class_loader();
944 oop protection_domain = this->protection_domain();
945 Klass* klass = SystemDictionary::resolve_or_fail(symb,
946 Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
947 CHECK_false);
948 if (klass == nullptr) {
949 THROW_(vmSymbols::java_lang_LinkageError(), false);
950 }
951 if (!klass->is_inline_klass()) {
952 Exceptions::fthrow(
953 THREAD_AND_LOCATION,
954 vmSymbols::java_lang_IncompatibleClassChangeError(),
955 "class %s is not an inline type",
956 klass->external_name());
957 }
958 }
959 }
960 }
961 }
962 }
963 // Aggressively preloading all classes from the Preload attribute
964 if (preload_classes() != nullptr) {
965 for (int i = 0; i < preload_classes()->length(); i++) {
966 if (constants()->tag_at(preload_classes()->at(i)).is_klass()) continue;
967 Symbol* class_name = constants()->klass_at_noresolve(preload_classes()->at(i));
968 if (class_name == name()) continue;
969 oop loader = class_loader();
970 oop protection_domain = this->protection_domain();
971 Klass* klass = SystemDictionary::resolve_or_null(class_name,
972 Handle(THREAD, loader), Handle(THREAD, protection_domain), THREAD);
973 if (HAS_PENDING_EXCEPTION) {
974 CLEAR_PENDING_EXCEPTION;
975 }
976 if (klass != nullptr) {
977 log_info(class, preload)("Preloading class %s during linking of class %s because of its Preload attribute", class_name->as_C_string(), name()->as_C_string());
978 } else {
979 log_warning(class, preload)("Preloading of class %s during linking of class %s (Preload attribute) failed", class_name->as_C_string(), name()->as_C_string());
980 }
981 }
982 }
983 }
984
985 // in case the class is linked in the process of linking its superclasses
986 if (is_linked()) {
987 return true;
988 }
989
990 // trace only the link time for this klass that includes
991 // the verification time
992 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
993 ClassLoader::perf_class_link_selftime(),
994 ClassLoader::perf_classes_linked(),
995 jt->get_thread_stat()->perf_recursion_counts_addr(),
996 jt->get_thread_stat()->perf_timers_addr(),
997 PerfClassTraceTime::CLASS_LINK);
998
999 // verification & rewriting
1000 {
1001 LockLinkState init_lock(this, jt);
1002
1003 // rewritten will have been set if loader constraint error found
1004 // on an earlier link attempt
1005 // don't verify or rewrite if already rewritten
1006 //
1007
1008 if (!is_linked()) {
1009 if (!is_rewritten()) {
1010 if (is_shared()) {
1011 assert(!verified_at_dump_time(), "must be");
1012 }
1013 {
1014 bool verify_ok = verify_code(THREAD);
1015 if (!verify_ok) {
1016 return false;
1017 }
1018 }
1019
1020 // Just in case a side-effect of verify linked this class already
1021 // (which can sometimes happen since the verifier loads classes
1022 // using custom class loaders, which are free to initialize things)
1023 if (is_linked()) {
1024 return true;
1025 }
1026
1027 // also sets rewritten
1028 rewrite_class(CHECK_false);
1029 } else if (is_shared()) {
1030 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
1031 }
1032
1033 // relocate jsrs and link methods after they are all rewritten
1034 link_methods(CHECK_false);
1035
1036 // Initialize the vtable and interface table after
1037 // methods have been rewritten since rewrite may
1038 // fabricate new Method*s.
1039 // also does loader constraint checking
1040 //
1041 // initialize_vtable and initialize_itable need to be rerun
1042 // for a shared class if
1043 // 1) the class is loaded by custom class loader or
1044 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
1045 // 3) the class was not verified during dump time
1046 bool need_init_table = true;
1047 if (is_shared() && verified_at_dump_time() &&
1048 SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
1049 need_init_table = false;
1050 }
1051 if (need_init_table) {
1052 vtable().initialize_vtable_and_check_constraints(CHECK_false);
1053 itable().initialize_itable_and_check_constraints(CHECK_false);
1054 }
1055 #ifdef ASSERT
1056 vtable().verify(tty, true);
1057 // In case itable verification is ever added.
1058 // itable().verify(tty, true);
1059 #endif
1060 set_initialization_state_and_notify(linked, THREAD);
1061 if (JvmtiExport::should_post_class_prepare()) {
1062 JvmtiExport::post_class_prepare(THREAD, this);
1063 }
1064 }
1065 }
1066 return true;
1067 }
1068
1069 // Rewrite the byte codes of all of the methods of a class.
1070 // The rewriter must be called exactly once. Rewriting must happen after
1071 // verification but before the first method of the class is executed.
1072 void InstanceKlass::rewrite_class(TRAPS) {
1073 assert(is_loaded(), "must be loaded");
1074 if (is_rewritten()) {
1075 assert(is_shared(), "rewriting an unshared class?");
1076 return;
1077 }
1078 Rewriter::rewrite(this, CHECK);
1079 set_rewritten();
1080 }
1081
1082 // Now relocate and link method entry points after class is rewritten.
1083 // This is outside is_rewritten flag. In case of an exception, it can be
1084 // executed more than once.
1085 void InstanceKlass::link_methods(TRAPS) {
1086 int len = methods()->length();
1087 for (int i = len-1; i >= 0; i--) {
1088 methodHandle m(THREAD, methods()->at(i));
1089
1090 // Set up method entry points for compiler and interpreter .
1091 m->link_method(m, CHECK);
1092 }
1093 }
1094
1095 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1096 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1097 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1098 for (int i = 0; i < local_interfaces()->length(); ++i) {
1099 InstanceKlass* ik = local_interfaces()->at(i);
1100
1101 // Initialization is depth first search ie. we start with top of the inheritance tree
1102 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1103 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1104 if (ik->has_nonstatic_concrete_methods()) {
1105 ik->initialize_super_interfaces(CHECK);
1106 }
1107
1108 // Only initialize() interfaces that "declare" concrete methods.
1109 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1110 ik->initialize(CHECK);
1111 }
1112 }
1113 }
1114
1115 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
1116 static InitializationErrorTable* _initialization_error_table;
1117
1118 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
1119 // Create the same exception with a message indicating the thread name,
1120 // and the StackTraceElements.
1121 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
1122 ResourceMark rm(current);
1123 if (init_error.is_null()) {
1124 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name());
1125
1126 // We failed to create the new exception, most likely due to either out-of-memory or
1127 // a stackoverflow error. If the original exception was either of those then we save
1128 // the shared, pre-allocated, stackless, instance of that exception.
1129 if (exception->klass() == vmClasses::StackOverflowError_klass()) {
1130 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name());
1131 init_error = Handle(current, Universe::class_init_stack_overflow_error());
1132 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) {
1133 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name());
1134 init_error = Handle(current, Universe::class_init_out_of_memory_error());
1135 } else {
1136 return;
1137 }
1138 }
1139
1140 MutexLocker ml(current, ClassInitError_lock);
1141 OopHandle elem = OopHandle(Universe::vm_global(), init_error());
1142 bool created;
1143 if (_initialization_error_table == nullptr) {
1144 _initialization_error_table = new (mtClass) InitializationErrorTable();
1145 }
1146 _initialization_error_table->put_if_absent(this, elem, &created);
1147 assert(created, "Initialization is single threaded");
1148 log_trace(class, init)("Initialization error added for class %s", external_name());
1149 }
1150
1151 oop InstanceKlass::get_initialization_error(JavaThread* current) {
1152 MutexLocker ml(current, ClassInitError_lock);
1153 if (_initialization_error_table == nullptr) {
1154 return nullptr;
1155 }
1156 OopHandle* h = _initialization_error_table->get(this);
1157 return (h != nullptr) ? h->resolve() : nullptr;
1158 }
1159
1160 // Need to remove entries for unloaded classes.
1161 void InstanceKlass::clean_initialization_error_table() {
1162 struct InitErrorTableCleaner {
1163 bool do_entry(const InstanceKlass* ik, OopHandle h) {
1164 if (!ik->is_loader_alive()) {
1165 h.release(Universe::vm_global());
1166 return true;
1167 } else {
1168 return false;
1169 }
1170 }
1171 };
1172
1173 assert_locked_or_safepoint(ClassInitError_lock);
1174 InitErrorTableCleaner cleaner;
1175 if (_initialization_error_table != nullptr) {
1176 _initialization_error_table->unlink(&cleaner);
1177 }
1178 }
1179
1180 void InstanceKlass::initialize_impl(TRAPS) {
1181 HandleMark hm(THREAD);
1182
1183 // Make sure klass is linked (verified) before initialization
1184 // A class could already be verified, since it has been reflected upon.
1185 link_class(CHECK);
1186
1187 DTRACE_CLASSINIT_PROBE(required, -1);
1188
1189 bool wait = false;
1190 bool throw_error = false;
1191
1192 JavaThread* jt = THREAD;
1193
1194 // refer to the JVM book page 47 for description of steps
1195 // Step 1
1196 {
1197 MonitorLocker ml(THREAD, _init_monitor);
1198
1199 // Step 2
1200 while (is_being_initialized() && !is_init_thread(jt)) {
1201 wait = true;
1202 jt->set_class_to_be_initialized(this);
1203 ml.wait();
1204 jt->set_class_to_be_initialized(nullptr);
1205 }
1206
1207 // Step 3
1208 if (is_being_initialized() && is_init_thread(jt)) {
1209 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1210 return;
1211 }
1212
1213 // Step 4
1214 if (is_initialized()) {
1215 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1216 return;
1217 }
1218
1219 // Step 5
1220 if (is_in_error_state()) {
1221 throw_error = true;
1222 } else {
1223
1224 // Step 6
1225 set_init_state(being_initialized);
1226 set_init_thread(jt);
1227 }
1228 }
1229
1230 // Throw error outside lock
1231 if (throw_error) {
1232 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1233 ResourceMark rm(THREAD);
1234 Handle cause(THREAD, get_initialization_error(THREAD));
1235
1236 stringStream ss;
1237 ss.print("Could not initialize class %s", external_name());
1238 if (cause.is_null()) {
1239 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
1240 } else {
1241 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
1242 ss.as_string(), cause);
1243 }
1244 }
1245
1246 // Pre-allocating an instance of the default value
1247 if (is_inline_klass()) {
1248 InlineKlass* vk = InlineKlass::cast(this);
1249 oop val = vk->allocate_instance(THREAD);
1250 if (HAS_PENDING_EXCEPTION) {
1251 Handle e(THREAD, PENDING_EXCEPTION);
1252 CLEAR_PENDING_EXCEPTION;
1253 {
1254 EXCEPTION_MARK;
1255 add_initialization_error(THREAD, e);
1256 // Locks object, set state, and notify all waiting threads
1257 set_initialization_state_and_notify(initialization_error, THREAD);
1258 CLEAR_PENDING_EXCEPTION;
1259 }
1260 THROW_OOP(e());
1261 }
1262 vk->set_default_value(val);
1263 }
1264
1265 // Step 7
1266 // Next, if C is a class rather than an interface, initialize it's super class and super
1267 // interfaces.
1268 if (!is_interface()) {
1269 Klass* super_klass = super();
1270 if (super_klass != nullptr && super_klass->should_be_initialized()) {
1271 super_klass->initialize(THREAD);
1272 }
1273 // If C implements any interface that declares a non-static, concrete method,
1274 // the initialization of C triggers initialization of its super interfaces.
1275 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1276 // having a superinterface that declares, non-static, concrete methods
1277 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1278 initialize_super_interfaces(THREAD);
1279 }
1280
1281 // If any exceptions, complete abruptly, throwing the same exception as above.
1282 if (HAS_PENDING_EXCEPTION) {
1283 Handle e(THREAD, PENDING_EXCEPTION);
1284 CLEAR_PENDING_EXCEPTION;
1285 {
1286 EXCEPTION_MARK;
1287 add_initialization_error(THREAD, e);
1288 // Locks object, set state, and notify all waiting threads
1289 set_initialization_state_and_notify(initialization_error, THREAD);
1290 CLEAR_PENDING_EXCEPTION;
1291 }
1292 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1293 THROW_OOP(e());
1294 }
1295 }
1296
1297 // Step 8
1298 // Initialize classes of inline fields
1299 if (EnablePrimitiveClasses) {
1300 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1301 if (fs.is_null_free_inline_type()) {
1302 Klass* klass = get_inline_type_field_klass_or_null(fs.index());
1303 if (fs.access_flags().is_static() && klass == nullptr) {
1304 klass = SystemDictionary::resolve_or_fail(field_signature(fs.index())->fundamental_name(THREAD),
1305 Handle(THREAD, class_loader()),
1306 Handle(THREAD, protection_domain()),
1307 true, THREAD);
1308 set_inline_type_field_klass(fs.index(), klass);
1309 }
1310
1311 if (!HAS_PENDING_EXCEPTION) {
1312 assert(klass != nullptr, "Must be");
1313 InstanceKlass::cast(klass)->initialize(THREAD);
1314 if (fs.access_flags().is_static()) {
1315 if (java_mirror()->obj_field(fs.offset()) == nullptr) {
1316 java_mirror()->obj_field_put(fs.offset(), InlineKlass::cast(klass)->default_value());
1317 }
1318 }
1319 }
1320
1321 if (HAS_PENDING_EXCEPTION) {
1322 Handle e(THREAD, PENDING_EXCEPTION);
1323 CLEAR_PENDING_EXCEPTION;
1324 {
1325 EXCEPTION_MARK;
1326 add_initialization_error(THREAD, e);
1327 // Locks object, set state, and notify all waiting threads
1328 set_initialization_state_and_notify(initialization_error, THREAD);
1329 CLEAR_PENDING_EXCEPTION;
1330 }
1331 THROW_OOP(e());
1332 }
1333 }
1334 }
1335 }
1336
1337
1338 // Step 9
1339 {
1340 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1341 if (class_initializer() != nullptr) {
1342 // Timer includes any side effects of class initialization (resolution,
1343 // etc), but not recursive entry into call_class_initializer().
1344 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1345 ClassLoader::perf_class_init_selftime(),
1346 ClassLoader::perf_classes_inited(),
1347 jt->get_thread_stat()->perf_recursion_counts_addr(),
1348 jt->get_thread_stat()->perf_timers_addr(),
1349 PerfClassTraceTime::CLASS_CLINIT);
1350 call_class_initializer(THREAD);
1351 } else {
1352 // The elapsed time is so small it's not worth counting.
1353 if (UsePerfData) {
1354 ClassLoader::perf_classes_inited()->inc();
1355 }
1356 call_class_initializer(THREAD);
1357 }
1358 }
1359
1360 // Step 10
1361 if (!HAS_PENDING_EXCEPTION) {
1362 set_initialization_state_and_notify(fully_initialized, THREAD);
1363 debug_only(vtable().verify(tty, true);)
1364 }
1365 else {
1366 // Step 11 and 12
1367 Handle e(THREAD, PENDING_EXCEPTION);
1368 CLEAR_PENDING_EXCEPTION;
1369 // JVMTI has already reported the pending exception
1370 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1371 JvmtiExport::clear_detected_exception(jt);
1372 {
1373 EXCEPTION_MARK;
1374 add_initialization_error(THREAD, e);
1375 set_initialization_state_and_notify(initialization_error, THREAD);
1376 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1377 // JVMTI has already reported the pending exception
1378 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1379 JvmtiExport::clear_detected_exception(jt);
1380 }
1381 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1382 if (e->is_a(vmClasses::Error_klass())) {
1383 THROW_OOP(e());
1384 } else {
1385 JavaCallArguments args(e);
1386 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1387 vmSymbols::throwable_void_signature(),
1388 &args);
1389 }
1390 }
1391 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1392 }
1393
1394
1395 void InstanceKlass::set_initialization_state_and_notify(ClassState state, JavaThread* current) {
1396 MonitorLocker ml(current, _init_monitor);
1397
1398 if (state == linked && UseVtableBasedCHA && Universe::is_fully_initialized()) {
1399 DeoptimizationScope deopt_scope;
1400 {
1401 // Now mark all code that assumes the class is not linked.
1402 // Set state under the Compile_lock also.
1403 MutexLocker ml(current, Compile_lock);
1404
1405 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1406 set_init_state(state);
1407
1408 CodeCache::mark_dependents_on(&deopt_scope, this);
1409 }
1410 // Perform the deopt handshake outside Compile_lock.
1411 deopt_scope.deoptimize_marked();
1412 } else {
1413 set_init_thread(nullptr); // reset _init_thread before changing _init_state
1414 set_init_state(state);
1415 }
1416 ml.notify_all();
1417 }
1418
1419 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
1420 // is grabbed, to ensure that the compiler is not using the class hierarchy.
1421 void InstanceKlass::add_to_hierarchy(JavaThread* current) {
1422 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
1423
1424 // In case we are not using CHA based vtables we need to make sure the loaded
1425 // deopt is completed before anyone links this class.
1426 // Linking is done with _init_monitor held, by loading and deopting with it
1427 // held we make sure the deopt is completed before linking.
1428 if (!UseVtableBasedCHA) {
1429 init_monitor()->lock();
1430 }
1431
1432 DeoptimizationScope deopt_scope;
1433 {
1434 MutexLocker ml(current, Compile_lock);
1435
1436 set_init_state(InstanceKlass::loaded);
1437 // make sure init_state store is already done.
1438 // The compiler reads the hierarchy outside of the Compile_lock.
1439 // Access ordering is used to add to hierarchy.
1440
1441 // Link into hierarchy.
1442 append_to_sibling_list(); // add to superklass/sibling list
1443 process_interfaces(); // handle all "implements" declarations
1444
1445 // Now mark all code that depended on old class hierarchy.
1446 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1447 if (Universe::is_fully_initialized()) {
1448 CodeCache::mark_dependents_on(&deopt_scope, this);
1449 }
1450 }
1451 // Perform the deopt handshake outside Compile_lock.
1452 deopt_scope.deoptimize_marked();
1453
1454 if (!UseVtableBasedCHA) {
1455 init_monitor()->unlock();
1456 }
1457 }
1458
1459 InstanceKlass* InstanceKlass::implementor() const {
1460 InstanceKlass* volatile* ik = adr_implementor();
1461 if (ik == nullptr) {
1462 return nullptr;
1463 } else {
1464 // This load races with inserts, and therefore needs acquire.
1465 InstanceKlass* ikls = Atomic::load_acquire(ik);
1466 if (ikls != nullptr && !ikls->is_loader_alive()) {
1467 return nullptr; // don't return unloaded class
1468 } else {
1469 return ikls;
1470 }
1471 }
1472 }
1473
1474
1475 void InstanceKlass::set_implementor(InstanceKlass* ik) {
1476 assert_locked_or_safepoint(Compile_lock);
1477 assert(is_interface(), "not interface");
1478 InstanceKlass* volatile* addr = adr_implementor();
1479 assert(addr != nullptr, "null addr");
1480 if (addr != nullptr) {
1481 Atomic::release_store(addr, ik);
1482 }
1483 }
1484
1485 int InstanceKlass::nof_implementors() const {
1486 InstanceKlass* ik = implementor();
1487 if (ik == nullptr) {
1488 return 0;
1489 } else if (ik != this) {
1490 return 1;
1491 } else {
1492 return 2;
1493 }
1494 }
1495
1496 // The embedded _implementor field can only record one implementor.
1497 // When there are more than one implementors, the _implementor field
1498 // is set to the interface Klass* itself. Following are the possible
1499 // values for the _implementor field:
1500 // null - no implementor
1501 // implementor Klass* - one implementor
1502 // self - more than one implementor
1503 //
1504 // The _implementor field only exists for interfaces.
1505 void InstanceKlass::add_implementor(InstanceKlass* ik) {
1506 if (Universe::is_fully_initialized()) {
1507 assert_lock_strong(Compile_lock);
1508 }
1509 assert(is_interface(), "not interface");
1510 // Filter out my subinterfaces.
1511 // (Note: Interfaces are never on the subklass list.)
1512 if (ik->is_interface()) return;
1513
1514 // Filter out subclasses whose supers already implement me.
1515 // (Note: CHA must walk subclasses of direct implementors
1516 // in order to locate indirect implementors.)
1517 InstanceKlass* super_ik = ik->java_super();
1518 if (super_ik != nullptr && super_ik->implements_interface(this))
1519 // We only need to check one immediate superclass, since the
1520 // implements_interface query looks at transitive_interfaces.
1521 // Any supers of the super have the same (or fewer) transitive_interfaces.
1522 return;
1523
1524 InstanceKlass* iklass = implementor();
1525 if (iklass == nullptr) {
1526 set_implementor(ik);
1527 } else if (iklass != this && iklass != ik) {
1528 // There is already an implementor. Use itself as an indicator of
1529 // more than one implementors.
1530 set_implementor(this);
1531 }
1532
1533 // The implementor also implements the transitive_interfaces
1534 for (int index = 0; index < local_interfaces()->length(); index++) {
1535 local_interfaces()->at(index)->add_implementor(ik);
1536 }
1537 }
1538
1539 void InstanceKlass::init_implementor() {
1540 if (is_interface()) {
1541 set_implementor(nullptr);
1542 }
1543 }
1544
1545
1546 void InstanceKlass::process_interfaces() {
1547 // link this class into the implementors list of every interface it implements
1548 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1549 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1550 InstanceKlass* interf = local_interfaces()->at(i);
1551 assert(interf->is_interface(), "expected interface");
1552 interf->add_implementor(this);
1553 }
1554 }
1555
1556 bool InstanceKlass::can_be_primary_super_slow() const {
1557 if (is_interface())
1558 return false;
1559 else
1560 return Klass::can_be_primary_super_slow();
1561 }
1562
1563 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1564 Array<InstanceKlass*>* transitive_interfaces) {
1565 // The secondaries are the implemented interfaces.
1566 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1567 int num_secondaries = num_extra_slots + interfaces->length();
1568 if (num_secondaries == 0) {
1569 // Must share this for correct bootstrapping!
1570 set_secondary_supers(Universe::the_empty_klass_array());
1571 return nullptr;
1572 } else if (num_extra_slots == 0) {
1573 // The secondary super list is exactly the same as the transitive interfaces, so
1574 // let's use it instead of making a copy.
1575 // Redefine classes has to be careful not to delete this!
1576 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1577 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1578 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1579 return nullptr;
1580 } else {
1581 // Copy transitive interfaces to a temporary growable array to be constructed
1582 // into the secondary super list with extra slots.
1583 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1584 for (int i = 0; i < interfaces->length(); i++) {
1585 secondaries->push(interfaces->at(i));
1586 }
1587 return secondaries;
1588 }
1589 }
1590
1591 bool InstanceKlass::implements_interface(Klass* k) const {
1592 if (this == k) return true;
1593 assert(k->is_interface(), "should be an interface class");
1594 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1595 if (transitive_interfaces()->at(i) == k) {
1596 return true;
1597 }
1598 }
1599 return false;
1600 }
1601
1602 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1603 // Verify direct super interface
1604 if (this == k) return true;
1605 assert(k->is_interface(), "should be an interface class");
1606 for (int i = 0; i < local_interfaces()->length(); i++) {
1607 if (local_interfaces()->at(i) == k) {
1608 return true;
1609 }
1610 }
1611 return false;
1612 }
1613
1614 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1615 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1616 size_t size = objArrayOopDesc::object_size(length);
1617 Klass* ak = array_klass(n, CHECK_NULL);
1618 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1619 /* do_zero */ true, CHECK_NULL);
1620 return o;
1621 }
1622
1623 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1624 if (TraceFinalizerRegistration) {
1625 tty->print("Registered ");
1626 i->print_value_on(tty);
1627 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
1628 }
1629 instanceHandle h_i(THREAD, i);
1630 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1631 JavaValue result(T_VOID);
1632 JavaCallArguments args(h_i);
1633 methodHandle mh(THREAD, Universe::finalizer_register_method());
1634 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1635 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
1636 return h_i();
1637 }
1638
1639 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1640 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1641 size_t size = size_helper(); // Query before forming handle.
1642
1643 instanceOop i;
1644
1645 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1646 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1647 i = register_finalizer(i, CHECK_NULL);
1648 }
1649 return i;
1650 }
1651
1652 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
1653 Klass* k = java_lang_Class::as_Klass(java_class);
1654 if (k == nullptr) {
1655 ResourceMark rm(THREAD);
1656 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
1657 }
1658 InstanceKlass* ik = cast(k);
1659 ik->check_valid_for_instantiation(false, CHECK_NULL);
1660 ik->initialize(CHECK_NULL);
1661 return ik->allocate_instance(THREAD);
1662 }
1663
1664 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1665 return instanceHandle(THREAD, allocate_instance(THREAD));
1666 }
1667
1668 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1669 if (is_interface() || is_abstract()) {
1670 ResourceMark rm(THREAD);
1671 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1672 : vmSymbols::java_lang_InstantiationException(), external_name());
1673 }
1674 if (this == vmClasses::Class_klass()) {
1675 ResourceMark rm(THREAD);
1676 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1677 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1678 }
1679 }
1680
1681 Klass* InstanceKlass::array_klass(int n, TRAPS) {
1682 // Need load-acquire for lock-free read
1683 if (array_klasses_acquire() == nullptr) {
1684 ResourceMark rm(THREAD);
1685 JavaThread *jt = THREAD;
1686 {
1687 // Atomic creation of array_klasses
1688 MutexLocker ma(THREAD, MultiArray_lock);
1689
1690 // Check if update has already taken place
1691 if (array_klasses() == nullptr) {
1692 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this,
1693 false, false, CHECK_NULL);
1694 // use 'release' to pair with lock-free load
1695 release_set_array_klasses(k);
1696 }
1697 }
1698 }
1699 // array_klasses() will always be set at this point
1700 ArrayKlass* ak = array_klasses();
1701 return ak->array_klass(n, THREAD);
1702 }
1703
1704 Klass* InstanceKlass::array_klass_or_null(int n) {
1705 // Need load-acquire for lock-free read
1706 ArrayKlass* ak = array_klasses_acquire();
1707 if (ak == nullptr) {
1708 return nullptr;
1709 } else {
1710 return ak->array_klass_or_null(n);
1711 }
1712 }
1713
1714 Klass* InstanceKlass::array_klass(TRAPS) {
1715 return array_klass(1, THREAD);
1716 }
1717
1718 Klass* InstanceKlass::array_klass_or_null() {
1719 return array_klass_or_null(1);
1720 }
1721
1722 static int call_class_initializer_counter = 0; // for debugging
1723
1724 Method* InstanceKlass::class_initializer() const {
1725 Method* clinit = find_method(
1726 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1727 if (clinit != nullptr && clinit->is_class_initializer()) {
1728 return clinit;
1729 }
1730 return nullptr;
1731 }
1732
1733 void InstanceKlass::call_class_initializer(TRAPS) {
1734 if (ReplayCompiles &&
1735 (ReplaySuppressInitializers == 1 ||
1736 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
1737 // Hide the existence of the initializer for the purpose of replaying the compile
1738 return;
1739 }
1740
1741 #if INCLUDE_CDS
1742 // This is needed to ensure the consistency of the archived heap objects.
1743 if (has_archived_enum_objs()) {
1744 assert(is_shared(), "must be");
1745 bool initialized = HeapShared::initialize_enum_klass(this, CHECK);
1746 if (initialized) {
1747 return;
1748 }
1749 }
1750 #endif
1751
1752 methodHandle h_method(THREAD, class_initializer());
1753 assert(!is_initialized(), "we cannot initialize twice");
1754 LogTarget(Info, class, init) lt;
1755 if (lt.is_enabled()) {
1756 ResourceMark rm(THREAD);
1757 LogStream ls(lt);
1758 ls.print("%d Initializing ", call_class_initializer_counter++);
1759 name()->print_value_on(&ls);
1760 ls.print_cr("%s (" PTR_FORMAT ")", h_method() == nullptr ? "(no method)" : "", p2i(this));
1761 }
1762 if (h_method() != nullptr) {
1763 JavaCallArguments args; // No arguments
1764 JavaValue result(T_VOID);
1765 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1766 }
1767 }
1768
1769
1770 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1771 InterpreterOopMap* entry_for) {
1772 // Lazily create the _oop_map_cache at first request
1773 // Lock-free access requires load_acquire.
1774 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1775 if (oop_map_cache == nullptr) {
1776 MutexLocker x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1777 // Check if _oop_map_cache was allocated while we were waiting for this lock
1778 if ((oop_map_cache = _oop_map_cache) == nullptr) {
1779 oop_map_cache = new OopMapCache();
1780 // Ensure _oop_map_cache is stable, since it is examined without a lock
1781 Atomic::release_store(&_oop_map_cache, oop_map_cache);
1782 }
1783 }
1784 // _oop_map_cache is constant after init; lookup below does its own locking.
1785 oop_map_cache->lookup(method, bci, entry_for);
1786 }
1787
1788
1789 FieldInfo InstanceKlass::field(int index) const {
1790 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1791 if (fs.index() == index) {
1792 return fs.to_FieldInfo();
1793 }
1794 }
1795 fatal("Field not found");
1796 return FieldInfo();
1797 }
1798
1799 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1800 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1801 Symbol* f_name = fs.name();
1802 Symbol* f_sig = fs.signature();
1803 if (f_name == name && f_sig == sig) {
1804 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1805 return true;
1806 }
1807 }
1808 return false;
1809 }
1810
1811
1812 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1813 const int n = local_interfaces()->length();
1814 for (int i = 0; i < n; i++) {
1815 Klass* intf1 = local_interfaces()->at(i);
1816 assert(intf1->is_interface(), "just checking type");
1817 // search for field in current interface
1818 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1819 assert(fd->is_static(), "interface field must be static");
1820 return intf1;
1821 }
1822 // search for field in direct superinterfaces
1823 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1824 if (intf2 != nullptr) return intf2;
1825 }
1826 // otherwise field lookup fails
1827 return nullptr;
1828 }
1829
1830
1831 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1832 // search order according to newest JVM spec (5.4.3.2, p.167).
1833 // 1) search for field in current klass
1834 if (find_local_field(name, sig, fd)) {
1835 return const_cast<InstanceKlass*>(this);
1836 }
1837 // 2) search for field recursively in direct superinterfaces
1838 { Klass* intf = find_interface_field(name, sig, fd);
1839 if (intf != nullptr) return intf;
1840 }
1841 // 3) apply field lookup recursively if superclass exists
1842 { Klass* supr = super();
1843 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1844 }
1845 // 4) otherwise field lookup fails
1846 return nullptr;
1847 }
1848
1849
1850 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1851 // search order according to newest JVM spec (5.4.3.2, p.167).
1852 // 1) search for field in current klass
1853 if (find_local_field(name, sig, fd)) {
1854 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1855 }
1856 // 2) search for field recursively in direct superinterfaces
1857 if (is_static) {
1858 Klass* intf = find_interface_field(name, sig, fd);
1859 if (intf != nullptr) return intf;
1860 }
1861 // 3) apply field lookup recursively if superclass exists
1862 { Klass* supr = super();
1863 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1864 }
1865 // 4) otherwise field lookup fails
1866 return nullptr;
1867 }
1868
1869 bool InstanceKlass::contains_field_offset(int offset) {
1870 if (this->is_inline_klass()) {
1871 InlineKlass* vk = InlineKlass::cast(this);
1872 return offset >= vk->first_field_offset() && offset < (vk->first_field_offset() + vk->get_exact_size_in_bytes());
1873 } else {
1874 fieldDescriptor fd;
1875 return find_field_from_offset(offset, false, &fd);
1876 }
1877 }
1878
1879 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1880 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1881 if (fs.offset() == offset) {
1882 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1883 if (fd->is_static() == is_static) return true;
1884 }
1885 }
1886 return false;
1887 }
1888
1889
1890 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1891 Klass* klass = const_cast<InstanceKlass*>(this);
1892 while (klass != nullptr) {
1893 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1894 return true;
1895 }
1896 klass = klass->super();
1897 }
1898 return false;
1899 }
1900
1901
1902 void InstanceKlass::methods_do(void f(Method* method)) {
1903 // Methods aren't stable until they are loaded. This can be read outside
1904 // a lock through the ClassLoaderData for profiling
1905 // Redefined scratch classes are on the list and need to be cleaned
1906 if (!is_loaded() && !is_scratch_class()) {
1907 return;
1908 }
1909
1910 int len = methods()->length();
1911 for (int index = 0; index < len; index++) {
1912 Method* m = methods()->at(index);
1913 assert(m->is_method(), "must be method");
1914 f(m);
1915 }
1916 }
1917
1918
1919 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1920 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1921 if (fs.access_flags().is_static()) {
1922 fieldDescriptor& fd = fs.field_descriptor();
1923 cl->do_field(&fd);
1924 }
1925 }
1926 }
1927
1928
1929 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1930 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1931 if (fs.access_flags().is_static()) {
1932 fieldDescriptor& fd = fs.field_descriptor();
1933 f(&fd, mirror, CHECK);
1934 }
1935 }
1936 }
1937
1938 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1939 InstanceKlass* super = superklass();
1940 if (super != nullptr) {
1941 super->do_nonstatic_fields(cl);
1942 }
1943 fieldDescriptor fd;
1944 int length = java_fields_count();
1945 for (int i = 0; i < length; i += 1) {
1946 fd.reinitialize(this, i);
1947 if (!fd.is_static()) {
1948 cl->do_field(&fd);
1949 }
1950 }
1951 }
1952
1953 // first in Pair is offset, second is index.
1954 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
1955 return a->first - b->first;
1956 }
1957
1958 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
1959 InstanceKlass* super = superklass();
1960 if (super != nullptr) {
1961 super->print_nonstatic_fields(cl);
1962 }
1963 ResourceMark rm;
1964 fieldDescriptor fd;
1965 // In DebugInfo nonstatic fields are sorted by offset.
1966 GrowableArray<Pair<int,int> > fields_sorted;
1967 int i = 0;
1968 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
1969 if (!fs.access_flags().is_static()) {
1970 fd = fs.field_descriptor();
1971 Pair<int,int> f(fs.offset(), fs.index());
1972 fields_sorted.push(f);
1973 i++;
1974 }
1975 }
1976 if (i > 0) {
1977 int length = i;
1978 assert(length == fields_sorted.length(), "duh");
1979 // _sort_Fn is defined in growableArray.hpp.
1980 fields_sorted.sort(compare_fields_by_offset);
1981 for (int i = 0; i < length; i++) {
1982 fd.reinitialize(this, fields_sorted.at(i).second);
1983 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
1984 cl->do_field(&fd);
1985 }
1986 }
1987 }
1988
1989 #ifdef ASSERT
1990 static int linear_search(const Array<Method*>* methods,
1991 const Symbol* name,
1992 const Symbol* signature) {
1993 const int len = methods->length();
1994 for (int index = 0; index < len; index++) {
1995 const Method* const m = methods->at(index);
1996 assert(m->is_method(), "must be method");
1997 if (m->signature() == signature && m->name() == name) {
1998 return index;
1999 }
2000 }
2001 return -1;
2002 }
2003 #endif
2004
2005 bool InstanceKlass::_disable_method_binary_search = false;
2006
2007 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
2008 int len = methods->length();
2009 int l = 0;
2010 int h = len - 1;
2011 while (l <= h) {
2012 Method* m = methods->at(l);
2013 if (m->name() == name) {
2014 return l;
2015 }
2016 l++;
2017 }
2018 return -1;
2019 }
2020
2021 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
2022 if (_disable_method_binary_search) {
2023 assert(DynamicDumpSharedSpaces, "must be");
2024 // At the final stage of dynamic dumping, the methods array may not be sorted
2025 // by ascending addresses of their names, so we can't use binary search anymore.
2026 // However, methods with the same name are still laid out consecutively inside the
2027 // methods array, so let's look for the first one that matches.
2028 return linear_search(methods, name);
2029 }
2030
2031 int len = methods->length();
2032 int l = 0;
2033 int h = len - 1;
2034
2035 // methods are sorted by ascending addresses of their names, so do binary search
2036 while (l <= h) {
2037 int mid = (l + h) >> 1;
2038 Method* m = methods->at(mid);
2039 assert(m->is_method(), "must be method");
2040 int res = m->name()->fast_compare(name);
2041 if (res == 0) {
2042 return mid;
2043 } else if (res < 0) {
2044 l = mid + 1;
2045 } else {
2046 h = mid - 1;
2047 }
2048 }
2049 return -1;
2050 }
2051
2052 // find_method looks up the name/signature in the local methods array
2053 Method* InstanceKlass::find_method(const Symbol* name,
2054 const Symbol* signature) const {
2055 return find_method_impl(name, signature,
2056 OverpassLookupMode::find,
2057 StaticLookupMode::find,
2058 PrivateLookupMode::find);
2059 }
2060
2061 Method* InstanceKlass::find_method_impl(const Symbol* name,
2062 const Symbol* signature,
2063 OverpassLookupMode overpass_mode,
2064 StaticLookupMode static_mode,
2065 PrivateLookupMode private_mode) const {
2066 return InstanceKlass::find_method_impl(methods(),
2067 name,
2068 signature,
2069 overpass_mode,
2070 static_mode,
2071 private_mode);
2072 }
2073
2074 // find_instance_method looks up the name/signature in the local methods array
2075 // and skips over static methods
2076 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
2077 const Symbol* name,
2078 const Symbol* signature,
2079 PrivateLookupMode private_mode) {
2080 Method* const meth = InstanceKlass::find_method_impl(methods,
2081 name,
2082 signature,
2083 OverpassLookupMode::find,
2084 StaticLookupMode::skip,
2085 private_mode);
2086 assert(((meth == nullptr) || !meth->is_static()),
2087 "find_instance_method should have skipped statics");
2088 return meth;
2089 }
2090
2091 // find_instance_method looks up the name/signature in the local methods array
2092 // and skips over static methods
2093 Method* InstanceKlass::find_instance_method(const Symbol* name,
2094 const Symbol* signature,
2095 PrivateLookupMode private_mode) const {
2096 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
2097 }
2098
2099 // Find looks up the name/signature in the local methods array
2100 // and filters on the overpass, static and private flags
2101 // This returns the first one found
2102 // note that the local methods array can have up to one overpass, one static
2103 // and one instance (private or not) with the same name/signature
2104 Method* InstanceKlass::find_local_method(const Symbol* name,
2105 const Symbol* signature,
2106 OverpassLookupMode overpass_mode,
2107 StaticLookupMode static_mode,
2108 PrivateLookupMode private_mode) const {
2109 return InstanceKlass::find_method_impl(methods(),
2110 name,
2111 signature,
2112 overpass_mode,
2113 static_mode,
2114 private_mode);
2115 }
2116
2117 // Find looks up the name/signature in the local methods array
2118 // and filters on the overpass, static and private flags
2119 // This returns the first one found
2120 // note that the local methods array can have up to one overpass, one static
2121 // and one instance (private or not) with the same name/signature
2122 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
2123 const Symbol* name,
2124 const Symbol* signature,
2125 OverpassLookupMode overpass_mode,
2126 StaticLookupMode static_mode,
2127 PrivateLookupMode private_mode) {
2128 return InstanceKlass::find_method_impl(methods,
2129 name,
2130 signature,
2131 overpass_mode,
2132 static_mode,
2133 private_mode);
2134 }
2135
2136 Method* InstanceKlass::find_method(const Array<Method*>* methods,
2137 const Symbol* name,
2138 const Symbol* signature) {
2139 return InstanceKlass::find_method_impl(methods,
2140 name,
2141 signature,
2142 OverpassLookupMode::find,
2143 StaticLookupMode::find,
2144 PrivateLookupMode::find);
2145 }
2146
2147 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
2148 const Symbol* name,
2149 const Symbol* signature,
2150 OverpassLookupMode overpass_mode,
2151 StaticLookupMode static_mode,
2152 PrivateLookupMode private_mode) {
2153 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
2154 return hit >= 0 ? methods->at(hit): nullptr;
2155 }
2156
2157 // true if method matches signature and conforms to skipping_X conditions.
2158 static bool method_matches(const Method* m,
2159 const Symbol* signature,
2160 bool skipping_overpass,
2161 bool skipping_static,
2162 bool skipping_private) {
2163 return ((m->signature() == signature) &&
2164 (!skipping_overpass || !m->is_overpass()) &&
2165 (!skipping_static || !m->is_static()) &&
2166 (!skipping_private || !m->is_private()));
2167 }
2168
2169 // Used directly for default_methods to find the index into the
2170 // default_vtable_indices, and indirectly by find_method
2171 // find_method_index looks in the local methods array to return the index
2172 // of the matching name/signature. If, overpass methods are being ignored,
2173 // the search continues to find a potential non-overpass match. This capability
2174 // is important during method resolution to prefer a static method, for example,
2175 // over an overpass method.
2176 // There is the possibility in any _method's array to have the same name/signature
2177 // for a static method, an overpass method and a local instance method
2178 // To correctly catch a given method, the search criteria may need
2179 // to explicitly skip the other two. For local instance methods, it
2180 // is often necessary to skip private methods
2181 int InstanceKlass::find_method_index(const Array<Method*>* methods,
2182 const Symbol* name,
2183 const Symbol* signature,
2184 OverpassLookupMode overpass_mode,
2185 StaticLookupMode static_mode,
2186 PrivateLookupMode private_mode) {
2187 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
2188 const bool skipping_static = (static_mode == StaticLookupMode::skip);
2189 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
2190 const int hit = quick_search(methods, name);
2191 if (hit != -1) {
2192 const Method* const m = methods->at(hit);
2193
2194 // Do linear search to find matching signature. First, quick check
2195 // for common case, ignoring overpasses if requested.
2196 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2197 return hit;
2198 }
2199
2200 // search downwards through overloaded methods
2201 int i;
2202 for (i = hit - 1; i >= 0; --i) {
2203 const Method* const m = methods->at(i);
2204 assert(m->is_method(), "must be method");
2205 if (m->name() != name) {
2206 break;
2207 }
2208 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2209 return i;
2210 }
2211 }
2212 // search upwards
2213 for (i = hit + 1; i < methods->length(); ++i) {
2214 const Method* const m = methods->at(i);
2215 assert(m->is_method(), "must be method");
2216 if (m->name() != name) {
2217 break;
2218 }
2219 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
2220 return i;
2221 }
2222 }
2223 // not found
2224 #ifdef ASSERT
2225 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
2226 linear_search(methods, name, signature);
2227 assert(-1 == index, "binary search should have found entry %d", index);
2228 #endif
2229 }
2230 return -1;
2231 }
2232
2233 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
2234 return find_method_by_name(methods(), name, end);
2235 }
2236
2237 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
2238 const Symbol* name,
2239 int* end_ptr) {
2240 assert(end_ptr != nullptr, "just checking");
2241 int start = quick_search(methods, name);
2242 int end = start + 1;
2243 if (start != -1) {
2244 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
2245 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
2246 *end_ptr = end;
2247 return start;
2248 }
2249 return -1;
2250 }
2251
2252 // uncached_lookup_method searches both the local class methods array and all
2253 // superclasses methods arrays, skipping any overpass methods in superclasses,
2254 // and possibly skipping private methods.
2255 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
2256 const Symbol* signature,
2257 OverpassLookupMode overpass_mode,
2258 PrivateLookupMode private_mode) const {
2259 OverpassLookupMode overpass_local_mode = overpass_mode;
2260 const Klass* klass = this;
2261 while (klass != nullptr) {
2262 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
2263 signature,
2264 overpass_local_mode,
2265 StaticLookupMode::find,
2266 private_mode);
2267 if (method != nullptr) {
2268 return method;
2269 }
2270 if (name == vmSymbols::object_initializer_name() ||
2271 name == vmSymbols::inline_factory_name()) {
2272 break; // <init> and <vnew> is never inherited
2273 }
2274 klass = klass->super();
2275 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
2276 }
2277 return nullptr;
2278 }
2279
2280 #ifdef ASSERT
2281 // search through class hierarchy and return true if this class or
2282 // one of the superclasses was redefined
2283 bool InstanceKlass::has_redefined_this_or_super() const {
2284 const Klass* klass = this;
2285 while (klass != nullptr) {
2286 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2287 return true;
2288 }
2289 klass = klass->super();
2290 }
2291 return false;
2292 }
2293 #endif
2294
2295 // lookup a method in the default methods list then in all transitive interfaces
2296 // Do NOT return private or static methods
2297 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2298 Symbol* signature) const {
2299 Method* m = nullptr;
2300 if (default_methods() != nullptr) {
2301 m = find_method(default_methods(), name, signature);
2302 }
2303 // Look up interfaces
2304 if (m == nullptr) {
2305 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2306 }
2307 return m;
2308 }
2309
2310 // lookup a method in all the interfaces that this class implements
2311 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2312 // They should only be found in the initial InterfaceMethodRef
2313 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2314 Symbol* signature,
2315 DefaultsLookupMode defaults_mode) const {
2316 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2317 int num_ifs = all_ifs->length();
2318 InstanceKlass *ik = nullptr;
2319 for (int i = 0; i < num_ifs; i++) {
2320 ik = all_ifs->at(i);
2321 Method* m = ik->lookup_method(name, signature);
2322 if (m != nullptr && m->is_public() && !m->is_static() &&
2323 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2324 return m;
2325 }
2326 }
2327 return nullptr;
2328 }
2329
2330 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
2331 :_st(st), _verbose(verbose) {
2332 ResourceMark rm;
2333 _st->print("%-18s ", "KlassAddr");
2334 _st->print("%-4s ", "Size");
2335 _st->print("%-20s ", "State");
2336 _st->print("%-7s ", "Flags");
2337 _st->print("%-5s ", "ClassName");
2338 _st->cr();
2339 }
2340
2341 void PrintClassClosure::do_klass(Klass* k) {
2342 ResourceMark rm;
2343 // klass pointer
2344 _st->print(PTR_FORMAT " ", p2i(k));
2345 // klass size
2346 _st->print("%4d ", k->size());
2347 // initialization state
2348 if (k->is_instance_klass()) {
2349 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
2350 } else {
2351 _st->print("%-20s ","");
2352 }
2353 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
2354 char buf[10];
2355 int i = 0;
2356 if (k->has_finalizer()) buf[i++] = 'F';
2357 if (k->is_instance_klass()) {
2358 InstanceKlass* ik = InstanceKlass::cast(k);
2359 if (ik->has_final_method()) buf[i++] = 'f';
2360 if (ik->is_rewritten()) buf[i++] = 'W';
2361 if (ik->is_contended()) buf[i++] = 'C';
2362 if (ik->has_been_redefined()) buf[i++] = 'R';
2363 if (ik->is_shared()) buf[i++] = 'S';
2364 }
2365 buf[i++] = '\0';
2366 _st->print("%-7s ", buf);
2367 // klass name
2368 _st->print("%-5s ", k->external_name());
2369 // end
2370 _st->cr();
2371 if (_verbose) {
2372 k->print_on(_st);
2373 }
2374 }
2375
2376 /* jni_id_for for jfieldIds only */
2377 JNIid* InstanceKlass::jni_id_for(int offset) {
2378 MutexLocker ml(JfieldIdCreation_lock);
2379 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
2380 if (probe == nullptr) {
2381 // Allocate new static field identifier
2382 probe = new JNIid(this, offset, jni_ids());
2383 set_jni_ids(probe);
2384 }
2385 return probe;
2386 }
2387
2388 u2 InstanceKlass::enclosing_method_data(int offset) const {
2389 const Array<jushort>* const inner_class_list = inner_classes();
2390 if (inner_class_list == nullptr) {
2391 return 0;
2392 }
2393 const int length = inner_class_list->length();
2394 if (length % inner_class_next_offset == 0) {
2395 return 0;
2396 }
2397 const int index = length - enclosing_method_attribute_size;
2398 assert(offset < enclosing_method_attribute_size, "invalid offset");
2399 return inner_class_list->at(index + offset);
2400 }
2401
2402 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2403 u2 method_index) {
2404 Array<jushort>* inner_class_list = inner_classes();
2405 assert (inner_class_list != nullptr, "_inner_classes list is not set up");
2406 int length = inner_class_list->length();
2407 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2408 int index = length - enclosing_method_attribute_size;
2409 inner_class_list->at_put(
2410 index + enclosing_method_class_index_offset, class_index);
2411 inner_class_list->at_put(
2412 index + enclosing_method_method_index_offset, method_index);
2413 }
2414 }
2415
2416 // Lookup or create a jmethodID.
2417 // This code is called by the VMThread and JavaThreads so the
2418 // locking has to be done very carefully to avoid deadlocks
2419 // and/or other cache consistency problems.
2420 //
2421 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2422 size_t idnum = (size_t)method_h->method_idnum();
2423 jmethodID* jmeths = methods_jmethod_ids_acquire();
2424 size_t length = 0;
2425 jmethodID id = nullptr;
2426
2427 // We use a double-check locking idiom here because this cache is
2428 // performance sensitive. In the normal system, this cache only
2429 // transitions from null to non-null which is safe because we use
2430 // release_set_methods_jmethod_ids() to advertise the new cache.
2431 // A partially constructed cache should never be seen by a racing
2432 // thread. We also use release_store() to save a new jmethodID
2433 // in the cache so a partially constructed jmethodID should never be
2434 // seen either. Cache reads of existing jmethodIDs proceed without a
2435 // lock, but cache writes of a new jmethodID requires uniqueness and
2436 // creation of the cache itself requires no leaks so a lock is
2437 // generally acquired in those two cases.
2438 //
2439 // If the RedefineClasses() API has been used, then this cache can
2440 // grow and we'll have transitions from non-null to bigger non-null.
2441 // Cache creation requires no leaks and we require safety between all
2442 // cache accesses and freeing of the old cache so a lock is generally
2443 // acquired when the RedefineClasses() API has been used.
2444
2445 if (jmeths != nullptr) {
2446 // the cache already exists
2447 if (!idnum_can_increment()) {
2448 // the cache can't grow so we can just get the current values
2449 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2450 } else {
2451 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2452 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2453 }
2454 }
2455 // implied else:
2456 // we need to allocate a cache so default length and id values are good
2457
2458 if (jmeths == nullptr || // no cache yet
2459 length <= idnum || // cache is too short
2460 id == nullptr) { // cache doesn't contain entry
2461
2462 // This function can be called by the VMThread or GC worker threads so we
2463 // have to do all things that might block on a safepoint before grabbing the lock.
2464 // Otherwise, we can deadlock with the VMThread or have a cache
2465 // consistency issue. These vars keep track of what we might have
2466 // to free after the lock is dropped.
2467 jmethodID to_dealloc_id = nullptr;
2468 jmethodID* to_dealloc_jmeths = nullptr;
2469
2470 // may not allocate new_jmeths or use it if we allocate it
2471 jmethodID* new_jmeths = nullptr;
2472 if (length <= idnum) {
2473 // allocate a new cache that might be used
2474 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
2475 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
2476 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
2477 // cache size is stored in element[0], other elements offset by one
2478 new_jmeths[0] = (jmethodID)size;
2479 }
2480
2481 // allocate a new jmethodID that might be used
2482 {
2483 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2484 jmethodID new_id = nullptr;
2485 if (method_h->is_old() && !method_h->is_obsolete()) {
2486 // The method passed in is old (but not obsolete), we need to use the current version
2487 Method* current_method = method_with_idnum((int)idnum);
2488 assert(current_method != nullptr, "old and but not obsolete, so should exist");
2489 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
2490 } else {
2491 // It is the current version of the method or an obsolete method,
2492 // use the version passed in
2493 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
2494 }
2495
2496 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2497 &to_dealloc_id, &to_dealloc_jmeths);
2498 }
2499
2500 // The lock has been dropped so we can free resources.
2501 // Free up either the old cache or the new cache if we allocated one.
2502 if (to_dealloc_jmeths != nullptr) {
2503 FreeHeap(to_dealloc_jmeths);
2504 }
2505 // free up the new ID since it wasn't needed
2506 if (to_dealloc_id != nullptr) {
2507 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2508 }
2509 }
2510 return id;
2511 }
2512
2513 // Figure out how many jmethodIDs haven't been allocated, and make
2514 // sure space for them is pre-allocated. This makes getting all
2515 // method ids much, much faster with classes with more than 8
2516 // methods, and has a *substantial* effect on performance with jvmti
2517 // code that loads all jmethodIDs for all classes.
2518 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2519 int new_jmeths = 0;
2520 int length = methods()->length();
2521 for (int index = start_offset; index < length; index++) {
2522 Method* m = methods()->at(index);
2523 jmethodID id = m->find_jmethod_id_or_null();
2524 if (id == nullptr) {
2525 new_jmeths++;
2526 }
2527 }
2528 if (new_jmeths != 0) {
2529 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2530 }
2531 }
2532
2533 // Common code to fetch the jmethodID from the cache or update the
2534 // cache with the new jmethodID. This function should never do anything
2535 // that causes the caller to go to a safepoint or we can deadlock with
2536 // the VMThread or have cache consistency issues.
2537 //
2538 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2539 size_t idnum, jmethodID new_id,
2540 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2541 jmethodID** to_dealloc_jmeths_p) {
2542 assert(new_id != nullptr, "sanity check");
2543 assert(to_dealloc_id_p != nullptr, "sanity check");
2544 assert(to_dealloc_jmeths_p != nullptr, "sanity check");
2545 assert(JmethodIdCreation_lock->owned_by_self(), "sanity check");
2546
2547 // reacquire the cache - we are locked, single threaded or at a safepoint
2548 jmethodID* jmeths = methods_jmethod_ids_acquire();
2549 jmethodID id = nullptr;
2550 size_t length = 0;
2551
2552 if (jmeths == nullptr || // no cache yet
2553 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2554 if (jmeths != nullptr) {
2555 // copy any existing entries from the old cache
2556 for (size_t index = 0; index < length; index++) {
2557 new_jmeths[index+1] = jmeths[index+1];
2558 }
2559 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2560 }
2561 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2562 } else {
2563 // fetch jmethodID (if any) from the existing cache
2564 id = jmeths[idnum+1];
2565 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2566 }
2567 if (id == nullptr) {
2568 // No matching jmethodID in the existing cache or we have a new
2569 // cache or we just grew the cache. This cache write is done here
2570 // by the first thread to win the foot race because a jmethodID
2571 // needs to be unique once it is generally available.
2572 id = new_id;
2573
2574 // The jmethodID cache can be read while unlocked so we have to
2575 // make sure the new jmethodID is complete before installing it
2576 // in the cache.
2577 Atomic::release_store(&jmeths[idnum+1], id);
2578 } else {
2579 *to_dealloc_id_p = new_id; // save new id for later delete
2580 }
2581 return id;
2582 }
2583
2584
2585 // Common code to get the jmethodID cache length and the jmethodID
2586 // value at index idnum if there is one.
2587 //
2588 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2589 size_t idnum, size_t *length_p, jmethodID* id_p) {
2590 assert(cache != nullptr, "sanity check");
2591 assert(length_p != nullptr, "sanity check");
2592 assert(id_p != nullptr, "sanity check");
2593
2594 // cache size is stored in element[0], other elements offset by one
2595 *length_p = (size_t)cache[0];
2596 if (*length_p <= idnum) { // cache is too short
2597 *id_p = nullptr;
2598 } else {
2599 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2600 }
2601 }
2602
2603
2604 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
2605 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2606 size_t idnum = (size_t)method->method_idnum();
2607 jmethodID* jmeths = methods_jmethod_ids_acquire();
2608 size_t length; // length assigned as debugging crumb
2609 jmethodID id = nullptr;
2610 if (jmeths != nullptr && // If there is a cache
2611 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2612 id = jmeths[idnum+1]; // Look up the id (may be null)
2613 }
2614 return id;
2615 }
2616
2617 inline DependencyContext InstanceKlass::dependencies() {
2618 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2619 return dep_context;
2620 }
2621
2622 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
2623 dependencies().mark_dependent_nmethods(deopt_scope, changes);
2624 }
2625
2626 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2627 dependencies().add_dependent_nmethod(nm);
2628 }
2629
2630 void InstanceKlass::clean_dependency_context() {
2631 dependencies().clean_unloading_dependents();
2632 }
2633
2634 #ifndef PRODUCT
2635 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2636 dependencies().print_dependent_nmethods(verbose);
2637 }
2638
2639 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2640 return dependencies().is_dependent_nmethod(nm);
2641 }
2642 #endif //PRODUCT
2643
2644 void InstanceKlass::clean_weak_instanceklass_links() {
2645 clean_implementors_list();
2646 clean_method_data();
2647 }
2648
2649 void InstanceKlass::clean_implementors_list() {
2650 assert(is_loader_alive(), "this klass should be live");
2651 if (is_interface()) {
2652 assert (ClassUnloading, "only called for ClassUnloading");
2653 for (;;) {
2654 // Use load_acquire due to competing with inserts
2655 InstanceKlass* impl = Atomic::load_acquire(adr_implementor());
2656 if (impl != nullptr && !impl->is_loader_alive()) {
2657 // null this field, might be an unloaded instance klass or null
2658 InstanceKlass* volatile* iklass = adr_implementor();
2659 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
2660 // Successfully unlinking implementor.
2661 if (log_is_enabled(Trace, class, unload)) {
2662 ResourceMark rm;
2663 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2664 }
2665 return;
2666 }
2667 } else {
2668 return;
2669 }
2670 }
2671 }
2672 }
2673
2674 void InstanceKlass::clean_method_data() {
2675 for (int m = 0; m < methods()->length(); m++) {
2676 MethodData* mdo = methods()->at(m)->method_data();
2677 if (mdo != nullptr) {
2678 MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? nullptr : mdo->extra_data_lock());
2679 mdo->clean_method_data(/*always_clean*/false);
2680 }
2681 }
2682 }
2683
2684 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2685 Klass::metaspace_pointers_do(it);
2686
2687 if (log_is_enabled(Trace, cds)) {
2688 ResourceMark rm;
2689 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2690 }
2691
2692 it->push(&_annotations);
2693 it->push((Klass**)&_array_klasses);
2694 if (!is_rewritten()) {
2695 it->push(&_constants, MetaspaceClosure::_writable);
2696 } else {
2697 it->push(&_constants);
2698 }
2699 it->push(&_inner_classes);
2700 #if INCLUDE_JVMTI
2701 it->push(&_previous_versions);
2702 #endif
2703 #if INCLUDE_CDS
2704 // For "old" classes with methods containing the jsr bytecode, the _methods array will
2705 // be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to
2706 // be writable. The length check on the _methods is necessary because classes which
2707 // don't have any methods share the Universe::_the_empty_method_array which is in the RO region.
2708 if (_methods != nullptr && _methods->length() > 0 &&
2709 !can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) {
2710 // To handle jsr bytecode, new Method* maybe stored into _methods
2711 it->push(&_methods, MetaspaceClosure::_writable);
2712 } else {
2713 #endif
2714 it->push(&_methods);
2715 #if INCLUDE_CDS
2716 }
2717 #endif
2718 it->push(&_default_methods);
2719 it->push(&_local_interfaces);
2720 it->push(&_transitive_interfaces);
2721 it->push(&_method_ordering);
2722 if (!is_rewritten()) {
2723 it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
2724 } else {
2725 it->push(&_default_vtable_indices);
2726 }
2727
2728 it->push(&_fieldinfo_stream);
2729 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
2730 it->push(&_fields_status, MetaspaceClosure::_writable);
2731
2732 if (itable_length() > 0) {
2733 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2734 int method_table_offset_in_words = ioe->offset()/wordSize;
2735 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
2736
2737 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
2738 / itableOffsetEntry::size();
2739
2740 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2741 if (ioe->interface_klass() != nullptr) {
2742 it->push(ioe->interface_klass_addr());
2743 itableMethodEntry* ime = ioe->first_method_entry(this);
2744 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2745 for (int index = 0; index < n; index ++) {
2746 it->push(ime[index].method_addr());
2747 }
2748 }
2749 }
2750 }
2751
2752 it->push(&_nest_members);
2753 it->push(&_permitted_subclasses);
2754 it->push(&_preload_classes);
2755 it->push(&_record_components);
2756
2757 if (has_inline_type_fields()) {
2758 for (int i = 0; i < java_fields_count(); i++) {
2759 it->push(&((Klass**)adr_inline_type_field_klasses())[i]);
2760 }
2761 }
2762 }
2763
2764 #if INCLUDE_CDS
2765 void InstanceKlass::remove_unshareable_info() {
2766
2767 if (is_linked()) {
2768 assert(can_be_verified_at_dumptime(), "must be");
2769 // Remember this so we can avoid walking the hierarchy at runtime.
2770 set_verified_at_dump_time();
2771 }
2772
2773 Klass::remove_unshareable_info();
2774
2775 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2776 // Classes are attempted to link during dumping and may fail,
2777 // but these classes are still in the dictionary and class list in CLD.
2778 // If the class has failed verification, there is nothing else to remove.
2779 return;
2780 }
2781
2782 // Reset to the 'allocated' state to prevent any premature accessing to
2783 // a shared class at runtime while the class is still being loaded and
2784 // restored. A class' init_state is set to 'loaded' at runtime when it's
2785 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
2786 _init_state = allocated;
2787
2788 { // Otherwise this needs to take out the Compile_lock.
2789 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2790 init_implementor();
2791 }
2792
2793 constants()->remove_unshareable_info();
2794
2795 for (int i = 0; i < methods()->length(); i++) {
2796 Method* m = methods()->at(i);
2797 m->remove_unshareable_info();
2798 }
2799
2800 // do array classes also.
2801 if (array_klasses() != nullptr) {
2802 array_klasses()->remove_unshareable_info();
2803 }
2804
2805 if (has_inline_type_fields()) {
2806 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
2807 if (fs.is_null_free_inline_type()) {
2808 reset_inline_type_field_klass(fs.index());
2809 }
2810 }
2811 }
2812
2813 // These are not allocated from metaspace. They are safe to set to nullptr.
2814 _source_debug_extension = nullptr;
2815 _dep_context = nullptr;
2816 _osr_nmethods_head = nullptr;
2817 #if INCLUDE_JVMTI
2818 _breakpoints = nullptr;
2819 _previous_versions = nullptr;
2820 _cached_class_file = nullptr;
2821 _jvmti_cached_class_field_map = nullptr;
2822 #endif
2823
2824 _init_thread = nullptr;
2825 _methods_jmethod_ids = nullptr;
2826 _jni_ids = nullptr;
2827 _oop_map_cache = nullptr;
2828 // clear _nest_host to ensure re-load at runtime
2829 _nest_host = nullptr;
2830 init_shared_package_entry();
2831 _dep_context_last_cleaned = 0;
2832 _init_monitor = nullptr;
2833
2834 remove_unshareable_flags();
2835 }
2836
2837 void InstanceKlass::remove_unshareable_flags() {
2838 // clear all the flags/stats that shouldn't be in the archived version
2839 assert(!is_scratch_class(), "must be");
2840 assert(!has_been_redefined(), "must be");
2841 #if INCLUDE_JVMTI
2842 set_is_being_redefined(false);
2843 #endif
2844 set_has_resolved_methods(false);
2845 }
2846
2847 void InstanceKlass::remove_java_mirror() {
2848 Klass::remove_java_mirror();
2849
2850 // do array classes also.
2851 if (array_klasses() != nullptr) {
2852 array_klasses()->remove_java_mirror();
2853 }
2854 }
2855
2856 void InstanceKlass::init_shared_package_entry() {
2857 #if !INCLUDE_CDS_JAVA_HEAP
2858 _package_entry = nullptr;
2859 #else
2860 if (!MetaspaceShared::use_full_module_graph()) {
2861 _package_entry = nullptr;
2862 } else if (DynamicDumpSharedSpaces) {
2863 if (!MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
2864 _package_entry = nullptr;
2865 }
2866 } else {
2867 if (is_shared_unregistered_class()) {
2868 _package_entry = nullptr;
2869 } else {
2870 _package_entry = PackageEntry::get_archived_entry(_package_entry);
2871 }
2872 }
2873 ArchivePtrMarker::mark_pointer((address**)&_package_entry);
2874 #endif
2875 }
2876
2877 void InstanceKlass::compute_has_loops_flag_for_methods() {
2878 Array<Method*>* methods = this->methods();
2879 for (int index = 0; index < methods->length(); ++index) {
2880 Method* m = methods->at(index);
2881 if (!m->is_overpass()) { // work around JDK-8305771
2882 m->compute_has_loops_flag();
2883 }
2884 }
2885 }
2886
2887 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2888 PackageEntry* pkg_entry, TRAPS) {
2889 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded
2890 // before the InstanceKlass is added to the SystemDictionary. Make
2891 // sure the current state is <loaded.
2892 assert(!is_loaded(), "invalid init state");
2893 assert(!shared_loading_failed(), "Must not try to load failed class again");
2894 set_package(loader_data, pkg_entry, CHECK);
2895 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2896
2897 if (is_inline_klass()) {
2898 InlineKlass::cast(this)->initialize_calling_convention(CHECK);
2899 }
2900
2901 Array<Method*>* methods = this->methods();
2902 int num_methods = methods->length();
2903 for (int index = 0; index < num_methods; ++index) {
2904 methods->at(index)->restore_unshareable_info(CHECK);
2905 }
2906 #if INCLUDE_JVMTI
2907 if (JvmtiExport::has_redefined_a_class()) {
2908 // Reinitialize vtable because RedefineClasses may have changed some
2909 // entries in this vtable for super classes so the CDS vtable might
2910 // point to old or obsolete entries. RedefineClasses doesn't fix up
2911 // vtables in the shared system dictionary, only the main one.
2912 // It also redefines the itable too so fix that too.
2913 // First fix any default methods that point to a super class that may
2914 // have been redefined.
2915 bool trace_name_printed = false;
2916 adjust_default_methods(&trace_name_printed);
2917 vtable().initialize_vtable();
2918 itable().initialize_itable();
2919 }
2920 #endif
2921
2922 // restore constant pool resolved references
2923 constants()->restore_unshareable_info(CHECK);
2924
2925 if (array_klasses() != nullptr) {
2926 // To get a consistent list of classes we need MultiArray_lock to ensure
2927 // array classes aren't observed while they are being restored.
2928 MutexLocker ml(MultiArray_lock);
2929 // Array classes have null protection domain.
2930 // --> see ArrayKlass::complete_create_array_klass()
2931 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2932 }
2933
2934 // Initialize @ValueBased class annotation
2935 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation()) {
2936 set_is_value_based();
2937 }
2938
2939 // restore the monitor
2940 _init_monitor = create_init_monitor("InstanceKlassInitMonitorRestored_lock");
2941 }
2942
2943 // Check if a class or any of its supertypes has a version older than 50.
2944 // CDS will not perform verification of old classes during dump time because
2945 // without changing the old verifier, the verification constraint cannot be
2946 // retrieved during dump time.
2947 // Verification of archived old classes will be performed during run time.
2948 bool InstanceKlass::can_be_verified_at_dumptime() const {
2949 if (MetaspaceShared::is_in_shared_metaspace(this)) {
2950 // This is a class that was dumped into the base archive, so we know
2951 // it was verified at dump time.
2952 return true;
2953 }
2954 if (major_version() < 50 /*JAVA_6_VERSION*/) {
2955 return false;
2956 }
2957 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
2958 return false;
2959 }
2960 Array<InstanceKlass*>* interfaces = local_interfaces();
2961 int len = interfaces->length();
2962 for (int i = 0; i < len; i++) {
2963 if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
2964 return false;
2965 }
2966 }
2967 return true;
2968 }
2969
2970 bool InstanceKlass::methods_contain_jsr_bytecode() const {
2971 Thread* thread = Thread::current();
2972 for (int i = 0; i < _methods->length(); i++) {
2973 methodHandle m(thread, _methods->at(i));
2974 BytecodeStream bcs(m);
2975 while (!bcs.is_last_bytecode()) {
2976 Bytecodes::Code opcode = bcs.next();
2977 if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) {
2978 return true;
2979 }
2980 }
2981 }
2982 return false;
2983 }
2984 #endif // INCLUDE_CDS
2985
2986 #if INCLUDE_JVMTI
2987 static void clear_all_breakpoints(Method* m) {
2988 m->clear_all_breakpoints();
2989 }
2990 #endif
2991
2992 void InstanceKlass::unload_class(InstanceKlass* ik) {
2993 // Release dependencies.
2994 ik->dependencies().remove_all_dependents();
2995
2996 // notify the debugger
2997 if (JvmtiExport::should_post_class_unload()) {
2998 JvmtiExport::post_class_unload(ik);
2999 }
3000
3001 // notify ClassLoadingService of class unload
3002 ClassLoadingService::notify_class_unloaded(ik);
3003
3004 SystemDictionaryShared::handle_class_unloading(ik);
3005
3006 if (log_is_enabled(Info, class, unload)) {
3007 ResourceMark rm;
3008 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
3009 }
3010
3011 Events::log_class_unloading(Thread::current(), ik);
3012
3013 #if INCLUDE_JFR
3014 assert(ik != nullptr, "invariant");
3015 EventClassUnload event;
3016 event.set_unloadedClass(ik);
3017 event.set_definingClassLoader(ik->class_loader_data());
3018 event.commit();
3019 #endif
3020 }
3021
3022 static void method_release_C_heap_structures(Method* m) {
3023 m->release_C_heap_structures();
3024 }
3025
3026 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
3027 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
3028 // Clean up C heap
3029 Klass::release_C_heap_structures();
3030
3031 // Deallocate and call destructors for MDO mutexes
3032 if (release_sub_metadata) {
3033 methods_do(method_release_C_heap_structures);
3034 }
3035
3036 // Destroy the init_monitor
3037 delete _init_monitor;
3038
3039 // Deallocate oop map cache
3040 if (_oop_map_cache != nullptr) {
3041 delete _oop_map_cache;
3042 _oop_map_cache = nullptr;
3043 }
3044
3045 // Deallocate JNI identifiers for jfieldIDs
3046 JNIid::deallocate(jni_ids());
3047 set_jni_ids(nullptr);
3048
3049 jmethodID* jmeths = methods_jmethod_ids_acquire();
3050 if (jmeths != (jmethodID*)nullptr) {
3051 release_set_methods_jmethod_ids(nullptr);
3052 FreeHeap(jmeths);
3053 }
3054
3055 assert(_dep_context == nullptr,
3056 "dependencies should already be cleaned");
3057
3058 #if INCLUDE_JVMTI
3059 // Deallocate breakpoint records
3060 if (breakpoints() != 0x0) {
3061 methods_do(clear_all_breakpoints);
3062 assert(breakpoints() == 0x0, "should have cleared breakpoints");
3063 }
3064
3065 // deallocate the cached class file
3066 if (_cached_class_file != nullptr) {
3067 os::free(_cached_class_file);
3068 _cached_class_file = nullptr;
3069 }
3070 #endif
3071
3072 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
3073
3074 if (release_sub_metadata) {
3075 constants()->release_C_heap_structures();
3076 }
3077 }
3078
3079 // The constant pool is on stack if any of the methods are executing or
3080 // referenced by handles.
3081 bool InstanceKlass::on_stack() const {
3082 return _constants->on_stack();
3083 }
3084
3085 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); }
3086 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); }
3087 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); }
3088
3089 // minor and major version numbers of class file
3090 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); }
3091 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); }
3092 u2 InstanceKlass::major_version() const { return _constants->major_version(); }
3093 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); }
3094
3095 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3096 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) {
3097 if (ik->constants()->version() == version) {
3098 return ik;
3099 }
3100 }
3101 return nullptr;
3102 }
3103
3104 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
3105 if (array == nullptr) {
3106 _source_debug_extension = nullptr;
3107 } else {
3108 // Adding one to the attribute length in order to store a null terminator
3109 // character could cause an overflow because the attribute length is
3110 // already coded with an u4 in the classfile, but in practice, it's
3111 // unlikely to happen.
3112 assert((length+1) > length, "Overflow checking");
3113 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
3114 for (int i = 0; i < length; i++) {
3115 sde[i] = array[i];
3116 }
3117 sde[length] = '\0';
3118 _source_debug_extension = sde;
3119 }
3120 }
3121
3122 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); }
3123 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); }
3124 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); }
3125
3126 const char* InstanceKlass::signature_name() const {
3127 return signature_name_of_carrier(JVM_SIGNATURE_CLASS);
3128 }
3129
3130 const char* InstanceKlass::signature_name_of_carrier(char c) const {
3131 // Get the internal name as a c string
3132 const char* src = (const char*) (name()->as_C_string());
3133 const int src_length = (int)strlen(src);
3134
3135 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
3136
3137 // Add L or Q as type indicator
3138 int dest_index = 0;
3139 dest[dest_index++] = c;
3140
3141 // Add the actual class name
3142 for (int src_index = 0; src_index < src_length; ) {
3143 dest[dest_index++] = src[src_index++];
3144 }
3145
3146 if (is_hidden()) { // Replace the last '+' with a '.'.
3147 for (int index = (int)src_length; index > 0; index--) {
3148 if (dest[index] == '+') {
3149 dest[index] = JVM_SIGNATURE_DOT;
3150 break;
3151 }
3152 }
3153 }
3154
3155 // Add the semicolon and the null
3156 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
3157 dest[dest_index] = '\0';
3158 return dest;
3159 }
3160
3161 ModuleEntry* InstanceKlass::module() const {
3162 if (is_hidden() &&
3163 in_unnamed_package() &&
3164 class_loader_data()->has_class_mirror_holder()) {
3165 // For a non-strong hidden class defined to an unnamed package,
3166 // its (class held) CLD will not have an unnamed module created for it.
3167 // Two choices to find the correct ModuleEntry:
3168 // 1. If hidden class is within a nest, use nest host's module
3169 // 2. Find the unnamed module off from the class loader
3170 // For now option #2 is used since a nest host is not set until
3171 // after the instance class is created in jvm_lookup_define_class().
3172 if (class_loader_data()->is_boot_class_loader_data()) {
3173 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
3174 } else {
3175 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
3176 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
3177 return java_lang_Module::module_entry(module);
3178 }
3179 }
3180
3181 // Class is in a named package
3182 if (!in_unnamed_package()) {
3183 return _package_entry->module();
3184 }
3185
3186 // Class is in an unnamed package, return its loader's unnamed module
3187 return class_loader_data()->unnamed_module();
3188 }
3189
3190 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
3191
3192 // ensure java/ packages only loaded by boot or platform builtin loaders
3193 // not needed for shared class since CDS does not archive prohibited classes.
3194 if (!is_shared()) {
3195 check_prohibited_package(name(), loader_data, CHECK);
3196 }
3197
3198 if (is_shared() && _package_entry != nullptr) {
3199 if (MetaspaceShared::use_full_module_graph() && _package_entry == pkg_entry) {
3200 // we can use the saved package
3201 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
3202 return;
3203 } else {
3204 _package_entry = nullptr;
3205 }
3206 }
3207
3208 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
3209 // it returns, so we need to decrement it when the current function exits.
3210 TempNewSymbol from_class_name =
3211 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
3212
3213 Symbol* pkg_name;
3214 if (pkg_entry != nullptr) {
3215 pkg_name = pkg_entry->name();
3216 } else {
3217 pkg_name = from_class_name;
3218 }
3219
3220 if (pkg_name != nullptr && loader_data != nullptr) {
3221
3222 // Find in class loader's package entry table.
3223 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
3224
3225 // If the package name is not found in the loader's package
3226 // entry table, it is an indication that the package has not
3227 // been defined. Consider it defined within the unnamed module.
3228 if (_package_entry == nullptr) {
3229
3230 if (!ModuleEntryTable::javabase_defined()) {
3231 // Before java.base is defined during bootstrapping, define all packages in
3232 // the java.base module. If a non-java.base package is erroneously placed
3233 // in the java.base module it will be caught later when java.base
3234 // is defined by ModuleEntryTable::verify_javabase_packages check.
3235 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
3236 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
3237 } else {
3238 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
3239 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
3240 }
3241
3242 // A package should have been successfully created
3243 DEBUG_ONLY(ResourceMark rm(THREAD));
3244 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
3245 name()->as_C_string(), loader_data->loader_name_and_id());
3246 }
3247
3248 if (log_is_enabled(Debug, module)) {
3249 ResourceMark rm(THREAD);
3250 ModuleEntry* m = _package_entry->module();
3251 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
3252 external_name(),
3253 pkg_name->as_C_string(),
3254 loader_data->loader_name_and_id(),
3255 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
3256 }
3257 } else {
3258 ResourceMark rm(THREAD);
3259 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
3260 external_name(),
3261 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
3262 UNNAMED_MODULE);
3263 }
3264 }
3265
3266 // Function set_classpath_index ensures that for a non-null _package_entry
3267 // of the InstanceKlass, the entry is in the boot loader's package entry table.
3268 // It then sets the classpath_index in the package entry record.
3269 //
3270 // The classpath_index field is used to find the entry on the boot loader class
3271 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
3272 // in an unnamed module. It is also used to indicate (for all packages whose
3273 // classes are loaded by the boot loader) that at least one of the package's
3274 // classes has been loaded.
3275 void InstanceKlass::set_classpath_index(s2 path_index) {
3276 if (_package_entry != nullptr) {
3277 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
3278 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
3279 assert(path_index != -1, "Unexpected classpath_index");
3280 _package_entry->set_classpath_index(path_index);
3281 }
3282 }
3283
3284 // different versions of is_same_class_package
3285
3286 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
3287 oop classloader1 = this->class_loader();
3288 PackageEntry* classpkg1 = this->package();
3289 if (class2->is_objArray_klass()) {
3290 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
3291 }
3292
3293 oop classloader2;
3294 PackageEntry* classpkg2;
3295 if (class2->is_instance_klass()) {
3296 classloader2 = class2->class_loader();
3297 classpkg2 = class2->package();
3298 } else {
3299 assert(class2->is_typeArray_klass(), "should be type array");
3300 classloader2 = nullptr;
3301 classpkg2 = nullptr;
3302 }
3303
3304 // Same package is determined by comparing class loader
3305 // and package entries. Both must be the same. This rule
3306 // applies even to classes that are defined in the unnamed
3307 // package, they still must have the same class loader.
3308 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
3309 return true;
3310 }
3311
3312 return false;
3313 }
3314
3315 // return true if this class and other_class are in the same package. Classloader
3316 // and classname information is enough to determine a class's package
3317 bool InstanceKlass::is_same_class_package(oop other_class_loader,
3318 const Symbol* other_class_name) const {
3319 if (class_loader() != other_class_loader) {
3320 return false;
3321 }
3322 if (name()->fast_compare(other_class_name) == 0) {
3323 return true;
3324 }
3325
3326 {
3327 ResourceMark rm;
3328
3329 bool bad_class_name = false;
3330 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
3331 if (bad_class_name) {
3332 return false;
3333 }
3334 // Check that package_from_class_name() returns null, not "", if there is no package.
3335 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
3336
3337 const Symbol* const this_package_name =
3338 this->package() != nullptr ? this->package()->name() : nullptr;
3339
3340 if (this_package_name == nullptr || other_pkg == nullptr) {
3341 // One of the two doesn't have a package. Only return true if the other
3342 // one also doesn't have a package.
3343 return this_package_name == other_pkg;
3344 }
3345
3346 // Check if package is identical
3347 return this_package_name->fast_compare(other_pkg) == 0;
3348 }
3349 }
3350
3351 static bool is_prohibited_package_slow(Symbol* class_name) {
3352 // Caller has ResourceMark
3353 int length;
3354 jchar* unicode = class_name->as_unicode(length);
3355 return (length >= 5 &&
3356 unicode[0] == 'j' &&
3357 unicode[1] == 'a' &&
3358 unicode[2] == 'v' &&
3359 unicode[3] == 'a' &&
3360 unicode[4] == '/');
3361 }
3362
3363 // Only boot and platform class loaders can define classes in "java/" packages.
3364 void InstanceKlass::check_prohibited_package(Symbol* class_name,
3365 ClassLoaderData* loader_data,
3366 TRAPS) {
3367 if (!loader_data->is_boot_class_loader_data() &&
3368 !loader_data->is_platform_class_loader_data() &&
3369 class_name != nullptr && class_name->utf8_length() >= 5) {
3370 ResourceMark rm(THREAD);
3371 bool prohibited;
3372 const u1* base = class_name->base();
3373 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
3374 prohibited = is_prohibited_package_slow(class_name);
3375 } else {
3376 char* name = class_name->as_C_string();
3377 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
3378 }
3379 if (prohibited) {
3380 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3381 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
3382 char* name = pkg_name->as_C_string();
3383 const char* class_loader_name = loader_data->loader_name_and_id();
3384 StringUtils::replace_no_expand(name, "/", ".");
3385 const char* msg_text1 = "Class loader (instance of): ";
3386 const char* msg_text2 = " tried to load prohibited package name: ";
3387 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3388 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3389 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3390 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3391 }
3392 }
3393 return;
3394 }
3395
3396 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3397 constantPoolHandle i_cp(THREAD, constants());
3398 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3399 int ioff = iter.inner_class_info_index();
3400 if (ioff != 0) {
3401 // Check to see if the name matches the class we're looking for
3402 // before attempting to find the class.
3403 if (i_cp->klass_name_at_matches(this, ioff)) {
3404 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3405 if (this == inner_klass) {
3406 *ooff = iter.outer_class_info_index();
3407 *noff = iter.inner_name_index();
3408 return true;
3409 }
3410 }
3411 }
3412 }
3413 return false;
3414 }
3415
3416 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3417 InstanceKlass* outer_klass = nullptr;
3418 *inner_is_member = false;
3419 int ooff = 0, noff = 0;
3420 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3421 if (has_inner_classes_attr) {
3422 constantPoolHandle i_cp(THREAD, constants());
3423 if (ooff != 0) {
3424 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3425 if (!ok->is_instance_klass()) {
3426 // If the outer class is not an instance klass then it cannot have
3427 // declared any inner classes.
3428 ResourceMark rm(THREAD);
3429 Exceptions::fthrow(
3430 THREAD_AND_LOCATION,
3431 vmSymbols::java_lang_IncompatibleClassChangeError(),
3432 "%s and %s disagree on InnerClasses attribute",
3433 ok->external_name(),
3434 external_name());
3435 return nullptr;
3436 }
3437 outer_klass = InstanceKlass::cast(ok);
3438 *inner_is_member = true;
3439 }
3440 if (nullptr == outer_klass) {
3441 // It may be a local class; try for that.
3442 int encl_method_class_idx = enclosing_method_class_index();
3443 if (encl_method_class_idx != 0) {
3444 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3445 outer_klass = InstanceKlass::cast(ok);
3446 *inner_is_member = false;
3447 }
3448 }
3449 }
3450
3451 // If no inner class attribute found for this class.
3452 if (nullptr == outer_klass) return nullptr;
3453
3454 // Throws an exception if outer klass has not declared k as an inner klass
3455 // We need evidence that each klass knows about the other, or else
3456 // the system could allow a spoof of an inner class to gain access rights.
3457 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3458 return outer_klass;
3459 }
3460
3461 jint InstanceKlass::compute_modifier_flags() const {
3462 jint access = access_flags().as_int();
3463
3464 // But check if it happens to be member class.
3465 InnerClassesIterator iter(this);
3466 for (; !iter.done(); iter.next()) {
3467 int ioff = iter.inner_class_info_index();
3468 // Inner class attribute can be zero, skip it.
3469 // Strange but true: JVM spec. allows null inner class refs.
3470 if (ioff == 0) continue;
3471
3472 // only look at classes that are already loaded
3473 // since we are looking for the flags for our self.
3474 Symbol* inner_name = constants()->klass_name_at(ioff);
3475 if (name() == inner_name) {
3476 // This is really a member class.
3477 access = iter.inner_access_flags();
3478 break;
3479 }
3480 }
3481 return (access & JVM_ACC_WRITTEN_FLAGS);
3482 }
3483
3484 jint InstanceKlass::jvmti_class_status() const {
3485 jint result = 0;
3486
3487 if (is_linked()) {
3488 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3489 }
3490
3491 if (is_initialized()) {
3492 assert(is_linked(), "Class status is not consistent");
3493 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3494 }
3495 if (is_in_error_state()) {
3496 result |= JVMTI_CLASS_STATUS_ERROR;
3497 }
3498 return result;
3499 }
3500
3501 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
3502 bool implements_interface; // initialized by method_at_itable_or_null
3503 Method* m = method_at_itable_or_null(holder, index,
3504 implements_interface); // out parameter
3505 if (m != nullptr) {
3506 assert(implements_interface, "sanity");
3507 return m;
3508 } else if (implements_interface) {
3509 // Throw AbstractMethodError since corresponding itable slot is empty.
3510 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3511 } else {
3512 // If the interface isn't implemented by the receiver class,
3513 // the VM should throw IncompatibleClassChangeError.
3514 ResourceMark rm(THREAD);
3515 stringStream ss;
3516 bool same_module = (module() == holder->module());
3517 ss.print("Receiver class %s does not implement "
3518 "the interface %s defining the method to be called "
3519 "(%s%s%s)",
3520 external_name(), holder->external_name(),
3521 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3522 (same_module) ? "" : "; ",
3523 (same_module) ? "" : holder->class_in_module_of_loader());
3524 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3525 }
3526 }
3527
3528 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
3529 klassItable itable(this);
3530 for (int i = 0; i < itable.size_offset_table(); i++) {
3531 itableOffsetEntry* offset_entry = itable.offset_entry(i);
3532 if (offset_entry->interface_klass() == holder) {
3533 implements_interface = true;
3534 itableMethodEntry* ime = offset_entry->first_method_entry(this);
3535 Method* m = ime[index].method();
3536 return m;
3537 }
3538 }
3539 implements_interface = false;
3540 return nullptr; // offset entry not found
3541 }
3542
3543 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
3544 assert(is_linked(), "required");
3545 assert(intf_method->method_holder()->is_interface(), "not an interface method");
3546 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
3547
3548 int vtable_index = Method::invalid_vtable_index;
3549 Symbol* name = intf_method->name();
3550 Symbol* signature = intf_method->signature();
3551
3552 // First check in default method array
3553 if (!intf_method->is_abstract() && default_methods() != nullptr) {
3554 int index = find_method_index(default_methods(),
3555 name, signature,
3556 Klass::OverpassLookupMode::find,
3557 Klass::StaticLookupMode::find,
3558 Klass::PrivateLookupMode::find);
3559 if (index >= 0) {
3560 vtable_index = default_vtable_indices()->at(index);
3561 }
3562 }
3563 if (vtable_index == Method::invalid_vtable_index) {
3564 // get vtable_index for miranda methods
3565 klassVtable vt = vtable();
3566 vtable_index = vt.index_of_miranda(name, signature);
3567 }
3568 return vtable_index;
3569 }
3570
3571 #if INCLUDE_JVMTI
3572 // update default_methods for redefineclasses for methods that are
3573 // not yet in the vtable due to concurrent subclass define and superinterface
3574 // redefinition
3575 // Note: those in the vtable, should have been updated via adjust_method_entries
3576 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3577 // search the default_methods for uses of either obsolete or EMCP methods
3578 if (default_methods() != nullptr) {
3579 for (int index = 0; index < default_methods()->length(); index ++) {
3580 Method* old_method = default_methods()->at(index);
3581 if (old_method == nullptr || !old_method->is_old()) {
3582 continue; // skip uninteresting entries
3583 }
3584 assert(!old_method->is_deleted(), "default methods may not be deleted");
3585 Method* new_method = old_method->get_new_method();
3586 default_methods()->at_put(index, new_method);
3587
3588 if (log_is_enabled(Info, redefine, class, update)) {
3589 ResourceMark rm;
3590 if (!(*trace_name_printed)) {
3591 log_info(redefine, class, update)
3592 ("adjust: klassname=%s default methods from name=%s",
3593 external_name(), old_method->method_holder()->external_name());
3594 *trace_name_printed = true;
3595 }
3596 log_debug(redefine, class, update, vtables)
3597 ("default method update: %s(%s) ",
3598 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3599 }
3600 }
3601 }
3602 }
3603 #endif // INCLUDE_JVMTI
3604
3605 // On-stack replacement stuff
3606 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3607 assert_lock_strong(CompiledMethod_lock);
3608 #ifndef PRODUCT
3609 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3610 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3611 "redundant OSR recompilation detected. memory leak in CodeCache!");
3612 #endif
3613 // only one compilation can be active
3614 assert(n->is_osr_method(), "wrong kind of nmethod");
3615 n->set_osr_link(osr_nmethods_head());
3616 set_osr_nmethods_head(n);
3617 // Raise the highest osr level if necessary
3618 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
3619
3620 // Get rid of the osr methods for the same bci that have lower levels.
3621 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3622 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3623 if (inv != nullptr && inv->is_in_use()) {
3624 inv->make_not_entrant();
3625 }
3626 }
3627 }
3628
3629 // Remove osr nmethod from the list. Return true if found and removed.
3630 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3631 // This is a short non-blocking critical region, so the no safepoint check is ok.
3632 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock
3633 , Mutex::_no_safepoint_check_flag);
3634 assert(n->is_osr_method(), "wrong kind of nmethod");
3635 nmethod* last = nullptr;
3636 nmethod* cur = osr_nmethods_head();
3637 int max_level = CompLevel_none; // Find the max comp level excluding n
3638 Method* m = n->method();
3639 // Search for match
3640 bool found = false;
3641 while(cur != nullptr && cur != n) {
3642 if (m == cur->method()) {
3643 // Find max level before n
3644 max_level = MAX2(max_level, cur->comp_level());
3645 }
3646 last = cur;
3647 cur = cur->osr_link();
3648 }
3649 nmethod* next = nullptr;
3650 if (cur == n) {
3651 found = true;
3652 next = cur->osr_link();
3653 if (last == nullptr) {
3654 // Remove first element
3655 set_osr_nmethods_head(next);
3656 } else {
3657 last->set_osr_link(next);
3658 }
3659 }
3660 n->set_osr_link(nullptr);
3661 cur = next;
3662 while (cur != nullptr) {
3663 // Find max level after n
3664 if (m == cur->method()) {
3665 max_level = MAX2(max_level, cur->comp_level());
3666 }
3667 cur = cur->osr_link();
3668 }
3669 m->set_highest_osr_comp_level(max_level);
3670 return found;
3671 }
3672
3673 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
3674 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock,
3675 Mutex::_no_safepoint_check_flag);
3676 nmethod* osr = osr_nmethods_head();
3677 int found = 0;
3678 while (osr != nullptr) {
3679 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3680 if (osr->method() == m) {
3681 deopt_scope->mark(osr);
3682 found++;
3683 }
3684 osr = osr->osr_link();
3685 }
3686 return found;
3687 }
3688
3689 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3690 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock,
3691 Mutex::_no_safepoint_check_flag);
3692 nmethod* osr = osr_nmethods_head();
3693 nmethod* best = nullptr;
3694 while (osr != nullptr) {
3695 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3696 // There can be a time when a c1 osr method exists but we are waiting
3697 // for a c2 version. When c2 completes its osr nmethod we will trash
3698 // the c1 version and only be able to find the c2 version. However
3699 // while we overflow in the c1 code at back branches we don't want to
3700 // try and switch to the same code as we are already running
3701
3702 if (osr->method() == m &&
3703 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3704 if (match_level) {
3705 if (osr->comp_level() == comp_level) {
3706 // Found a match - return it.
3707 return osr;
3708 }
3709 } else {
3710 if (best == nullptr || (osr->comp_level() > best->comp_level())) {
3711 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
3712 // Found the best possible - return it.
3713 return osr;
3714 }
3715 best = osr;
3716 }
3717 }
3718 }
3719 osr = osr->osr_link();
3720 }
3721
3722 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
3723 if (best != nullptr && best->comp_level() >= comp_level) {
3724 return best;
3725 }
3726 return nullptr;
3727 }
3728
3729 // -----------------------------------------------------------------------------------------------------
3730 // Printing
3731
3732 #define BULLET " - "
3733
3734 static const char* state_names[] = {
3735 "allocated", "loaded", "being_linked", "linked", "being_initialized", "fully_initialized", "initialization_error"
3736 };
3737
3738 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
3739 ResourceMark rm;
3740 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
3741 for (int i = 0; i < len; i++) forward_refs[i] = 0;
3742 for (int i = 0; i < len; i++) {
3743 intptr_t e = start[i];
3744 st->print("%d : " INTPTR_FORMAT, i, e);
3745 if (forward_refs[i] != 0) {
3746 int from = forward_refs[i];
3747 int off = (int) start[from];
3748 st->print(" (offset %d <= [%d])", off, from);
3749 }
3750 if (MetaspaceObj::is_valid((Metadata*)e)) {
3751 st->print(" ");
3752 ((Metadata*)e)->print_value_on(st);
3753 } else if (self != nullptr && e > 0 && e < 0x10000) {
3754 address location = self + e;
3755 int index = (int)((intptr_t*)location - start);
3756 st->print(" (offset %d => [%d])", (int)e, index);
3757 if (index >= 0 && index < len)
3758 forward_refs[index] = i;
3759 }
3760 st->cr();
3761 }
3762 }
3763
3764 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3765 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st);
3766 }
3767
3768 template<typename T>
3769 static void print_array_on(outputStream* st, Array<T>* array) {
3770 if (array == nullptr) { st->print_cr("nullptr"); return; }
3771 array->print_value_on(st); st->cr();
3772 if (Verbose || WizardMode) {
3773 for (int i = 0; i < array->length(); i++) {
3774 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
3775 }
3776 }
3777 }
3778
3779 static void print_array_on(outputStream* st, Array<int>* array) {
3780 if (array == nullptr) { st->print_cr("nullptr"); return; }
3781 array->print_value_on(st); st->cr();
3782 if (Verbose || WizardMode) {
3783 for (int i = 0; i < array->length(); i++) {
3784 st->print("%d : %d", i, array->at(i)); st->cr();
3785 }
3786 }
3787 }
3788
3789 const char* InstanceKlass::init_state_name() const {
3790 return state_names[init_state()];
3791 }
3792
3793 void InstanceKlass::print_on(outputStream* st) const {
3794 assert(is_klass(), "must be klass");
3795 Klass::print_on(st);
3796
3797 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3798 st->print(BULLET"klass size: %d", size()); st->cr();
3799 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3800 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
3801 st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
3802 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3803 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3804 st->print(BULLET"sub: ");
3805 Klass* sub = subklass();
3806 int n;
3807 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
3808 if (n < MaxSubklassPrintSize) {
3809 sub->print_value_on(st);
3810 st->print(" ");
3811 }
3812 }
3813 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3814 st->cr();
3815
3816 if (is_interface()) {
3817 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3818 if (nof_implementors() == 1) {
3819 st->print_cr(BULLET"implementor: ");
3820 st->print(" ");
3821 implementor()->print_value_on(st);
3822 st->cr();
3823 }
3824 }
3825
3826 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3827 st->print(BULLET"methods: "); print_array_on(st, methods());
3828 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3829 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3830 if (default_vtable_indices() != nullptr) {
3831 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3832 }
3833 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3834 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3835 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3836 if (class_loader_data() != nullptr) {
3837 st->print(BULLET"class loader data: ");
3838 class_loader_data()->print_value_on(st);
3839 st->cr();
3840 }
3841 if (source_file_name() != nullptr) {
3842 st->print(BULLET"source file: ");
3843 source_file_name()->print_value_on(st);
3844 st->cr();
3845 }
3846 if (source_debug_extension() != nullptr) {
3847 st->print(BULLET"source debug extension: ");
3848 st->print("%s", source_debug_extension());
3849 st->cr();
3850 }
3851 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3852 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3853 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3854 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3855 {
3856 bool have_pv = false;
3857 // previous versions are linked together through the InstanceKlass
3858 for (InstanceKlass* pv_node = previous_versions();
3859 pv_node != nullptr;
3860 pv_node = pv_node->previous_versions()) {
3861 if (!have_pv)
3862 st->print(BULLET"previous version: ");
3863 have_pv = true;
3864 pv_node->constants()->print_value_on(st);
3865 }
3866 if (have_pv) st->cr();
3867 }
3868
3869 if (generic_signature() != nullptr) {
3870 st->print(BULLET"generic signature: ");
3871 generic_signature()->print_value_on(st);
3872 st->cr();
3873 }
3874 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3875 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3876 if (record_components() != nullptr) {
3877 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr();
3878 }
3879 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3880 st->print(BULLET"preload classes: "); preload_classes()->print_value_on(st); st->cr();
3881 if (java_mirror() != nullptr) {
3882 st->print(BULLET"java mirror: ");
3883 java_mirror()->print_value_on(st);
3884 st->cr();
3885 } else {
3886 st->print_cr(BULLET"java mirror: null");
3887 }
3888 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3889 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3890 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3891 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st);
3892 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3893 FieldPrinter print_static_field(st);
3894 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3895 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3896 FieldPrinter print_nonstatic_field(st);
3897 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3898 ik->print_nonstatic_fields(&print_nonstatic_field);
3899
3900 st->print(BULLET"non-static oop maps: ");
3901 OopMapBlock* map = start_of_nonstatic_oop_maps();
3902 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3903 while (map < end_map) {
3904 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3905 map++;
3906 }
3907 st->cr();
3908 }
3909
3910 void InstanceKlass::print_value_on(outputStream* st) const {
3911 assert(is_klass(), "must be klass");
3912 if (Verbose || WizardMode) access_flags().print_on(st);
3913 name()->print_value_on(st);
3914 }
3915
3916 void FieldPrinter::do_field(fieldDescriptor* fd) {
3917 _st->print(BULLET);
3918 if (_obj == nullptr) {
3919 fd->print_on(_st);
3920 _st->cr();
3921 } else {
3922 fd->print_on_for(_st, _obj);
3923 _st->cr();
3924 }
3925 }
3926
3927
3928 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3929 Klass::oop_print_on(obj, st);
3930
3931 if (this == vmClasses::String_klass()) {
3932 typeArrayOop value = java_lang_String::value(obj);
3933 juint length = java_lang_String::length(obj);
3934 if (value != nullptr &&
3935 value->is_typeArray() &&
3936 length <= (juint) value->length()) {
3937 st->print(BULLET"string: ");
3938 java_lang_String::print(obj, st);
3939 st->cr();
3940 }
3941 }
3942
3943 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
3944 FieldPrinter print_field(st, obj);
3945 print_nonstatic_fields(&print_field);
3946
3947 if (this == vmClasses::Class_klass()) {
3948 st->print(BULLET"signature: ");
3949 java_lang_Class::print_signature(obj, st);
3950 st->cr();
3951 Klass* real_klass = java_lang_Class::as_Klass(obj);
3952 if (real_klass != nullptr && real_klass->is_instance_klass()) {
3953 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
3954 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3955 }
3956 } else if (this == vmClasses::MethodType_klass()) {
3957 st->print(BULLET"signature: ");
3958 java_lang_invoke_MethodType::print_signature(obj, st);
3959 st->cr();
3960 }
3961 }
3962
3963 #ifndef PRODUCT
3964
3965 bool InstanceKlass::verify_itable_index(int i) {
3966 int method_count = klassItable::method_count_for_interface(this);
3967 assert(i >= 0 && i < method_count, "index out of bounds");
3968 return true;
3969 }
3970
3971 #endif //PRODUCT
3972
3973 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3974 st->print("a ");
3975 name()->print_value_on(st);
3976 obj->print_address_on(st);
3977 if (this == vmClasses::String_klass()
3978 && java_lang_String::value(obj) != nullptr) {
3979 ResourceMark rm;
3980 int len = java_lang_String::length(obj);
3981 int plen = (len < 24 ? len : 12);
3982 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3983 st->print(" = \"%s\"", str);
3984 if (len > plen)
3985 st->print("...[%d]", len);
3986 } else if (this == vmClasses::Class_klass()) {
3987 Klass* k = java_lang_Class::as_Klass(obj);
3988 st->print(" = ");
3989 if (k != nullptr) {
3990 k->print_value_on(st);
3991 } else {
3992 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3993 st->print("%s", tname ? tname : "type?");
3994 }
3995 } else if (this == vmClasses::MethodType_klass()) {
3996 st->print(" = ");
3997 java_lang_invoke_MethodType::print_signature(obj, st);
3998 } else if (java_lang_boxing_object::is_instance(obj)) {
3999 st->print(" = ");
4000 java_lang_boxing_object::print(obj, st);
4001 } else if (this == vmClasses::LambdaForm_klass()) {
4002 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
4003 if (vmentry != nullptr) {
4004 st->print(" => ");
4005 vmentry->print_value_on(st);
4006 }
4007 } else if (this == vmClasses::MemberName_klass()) {
4008 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
4009 if (vmtarget != nullptr) {
4010 st->print(" = ");
4011 vmtarget->print_value_on(st);
4012 } else {
4013 oop clazz = java_lang_invoke_MemberName::clazz(obj);
4014 oop name = java_lang_invoke_MemberName::name(obj);
4015 if (clazz != nullptr) {
4016 clazz->print_value_on(st);
4017 } else {
4018 st->print("null");
4019 }
4020 st->print(".");
4021 if (name != nullptr) {
4022 name->print_value_on(st);
4023 } else {
4024 st->print("null");
4025 }
4026 }
4027 }
4028 }
4029
4030 const char* InstanceKlass::internal_name() const {
4031 return external_name();
4032 }
4033
4034 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
4035 const ModuleEntry* module_entry,
4036 const ClassFileStream* cfs) const {
4037
4038 if (ClassListWriter::is_enabled()) {
4039 ClassListWriter::write(this, cfs);
4040 }
4041
4042 print_class_load_helper(loader_data, module_entry, cfs);
4043 print_class_load_cause_logging();
4044 }
4045
4046 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data,
4047 const ModuleEntry* module_entry,
4048 const ClassFileStream* cfs) const {
4049
4050 if (!log_is_enabled(Info, class, load)) {
4051 return;
4052 }
4053
4054 ResourceMark rm;
4055 LogMessage(class, load) msg;
4056 stringStream info_stream;
4057
4058 // Name and class hierarchy info
4059 info_stream.print("%s", external_name());
4060
4061 // Source
4062 if (cfs != nullptr) {
4063 if (cfs->source() != nullptr) {
4064 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
4065 if (module_name != nullptr) {
4066 // When the boot loader created the stream, it didn't know the module name
4067 // yet. Let's format it now.
4068 if (cfs->from_boot_loader_modules_image()) {
4069 info_stream.print(" source: jrt:/%s", module_name);
4070 } else {
4071 info_stream.print(" source: %s", cfs->source());
4072 }
4073 } else {
4074 info_stream.print(" source: %s", cfs->source());
4075 }
4076 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
4077 Thread* current = Thread::current();
4078 Klass* caller = current->is_Java_thread() ?
4079 JavaThread::cast(current)->security_get_caller_class(1):
4080 nullptr;
4081 // caller can be null, for example, during a JVMTI VM_Init hook
4082 if (caller != nullptr) {
4083 info_stream.print(" source: instance of %s", caller->external_name());
4084 } else {
4085 // source is unknown
4086 }
4087 } else {
4088 oop class_loader = loader_data->class_loader();
4089 info_stream.print(" source: %s", class_loader->klass()->external_name());
4090 }
4091 } else {
4092 assert(this->is_shared(), "must be");
4093 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
4094 info_stream.print(" source: shared objects file (top)");
4095 } else {
4096 info_stream.print(" source: shared objects file");
4097 }
4098 }
4099
4100 msg.info("%s", info_stream.as_string());
4101
4102 if (log_is_enabled(Debug, class, load)) {
4103 stringStream debug_stream;
4104
4105 // Class hierarchy info
4106 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
4107 p2i(this), p2i(superklass()));
4108
4109 // Interfaces
4110 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
4111 debug_stream.print(" interfaces:");
4112 int length = local_interfaces()->length();
4113 for (int i = 0; i < length; i++) {
4114 debug_stream.print(" " PTR_FORMAT,
4115 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
4116 }
4117 }
4118
4119 // Class loader
4120 debug_stream.print(" loader: [");
4121 loader_data->print_value_on(&debug_stream);
4122 debug_stream.print("]");
4123
4124 // Classfile checksum
4125 if (cfs) {
4126 debug_stream.print(" bytes: %d checksum: %08x",
4127 cfs->length(),
4128 ClassLoader::crc32(0, (const char*)cfs->buffer(),
4129 cfs->length()));
4130 }
4131
4132 msg.debug("%s", debug_stream.as_string());
4133 }
4134 }
4135
4136 void InstanceKlass::print_class_load_cause_logging() const {
4137 bool log_cause_native = log_is_enabled(Info, class, load, cause, native);
4138 if (log_cause_native || log_is_enabled(Info, class, load, cause)) {
4139 JavaThread* current = JavaThread::current();
4140 ResourceMark rm(current);
4141 const char* name = external_name();
4142
4143 if (LogClassLoadingCauseFor == nullptr ||
4144 (strcmp("*", LogClassLoadingCauseFor) != 0 &&
4145 strstr(name, LogClassLoadingCauseFor) == nullptr)) {
4146 return;
4147 }
4148
4149 // Log Java stack first
4150 {
4151 LogMessage(class, load, cause) msg;
4152 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4153
4154 info_stream.print_cr("Java stack when loading %s:", name);
4155 current->print_stack_on(&info_stream);
4156 }
4157
4158 // Log native stack second
4159 if (log_cause_native) {
4160 // Log to string first so that lines can be indented
4161 stringStream stack_stream;
4162 char buf[O_BUFLEN];
4163 address lastpc = nullptr;
4164 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) {
4165 // We have printed the native stack in platform-specific code,
4166 // so nothing else to do in this case.
4167 } else {
4168 frame f = os::current_frame();
4169 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */,
4170 -1 /* max stack_stream */, buf, O_BUFLEN);
4171 }
4172
4173 LogMessage(class, load, cause, native) msg;
4174 NonInterleavingLogStream info_stream{LogLevelType::Info, msg};
4175 info_stream.print_cr("Native stack when loading %s:", name);
4176
4177 // Print each native stack line to the log
4178 int size = (int) stack_stream.size();
4179 char* stack = stack_stream.as_string();
4180 char* stack_end = stack + size;
4181 char* line_start = stack;
4182 for (char* p = stack; p < stack_end; p++) {
4183 if (*p == '\n') {
4184 *p = '\0';
4185 info_stream.print_cr("\t%s", line_start);
4186 line_start = p + 1;
4187 }
4188 }
4189 if (line_start < stack_end) {
4190 info_stream.print_cr("\t%s", line_start);
4191 }
4192 }
4193 }
4194 }
4195
4196 // Verification
4197
4198 class VerifyFieldClosure: public BasicOopIterateClosure {
4199 protected:
4200 template <class T> void do_oop_work(T* p) {
4201 oop obj = RawAccess<>::oop_load(p);
4202 if (!oopDesc::is_oop_or_null(obj)) {
4203 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
4204 Universe::print_on(tty);
4205 guarantee(false, "boom");
4206 }
4207 }
4208 public:
4209 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
4210 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
4211 };
4212
4213 void InstanceKlass::verify_on(outputStream* st) {
4214 #ifndef PRODUCT
4215 // Avoid redundant verifies, this really should be in product.
4216 if (_verify_count == Universe::verify_count()) return;
4217 _verify_count = Universe::verify_count();
4218 #endif
4219
4220 // Verify Klass
4221 Klass::verify_on(st);
4222
4223 // Verify that klass is present in ClassLoaderData
4224 guarantee(class_loader_data()->contains_klass(this),
4225 "this class isn't found in class loader data");
4226
4227 // Verify vtables
4228 if (is_linked()) {
4229 // $$$ This used to be done only for m/s collections. Doing it
4230 // always seemed a valid generalization. (DLD -- 6/00)
4231 vtable().verify(st);
4232 }
4233
4234 // Verify first subklass
4235 if (subklass() != nullptr) {
4236 guarantee(subklass()->is_klass(), "should be klass");
4237 }
4238
4239 // Verify siblings
4240 Klass* super = this->super();
4241 Klass* sib = next_sibling();
4242 if (sib != nullptr) {
4243 if (sib == this) {
4244 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
4245 }
4246
4247 guarantee(sib->is_klass(), "should be klass");
4248 guarantee(sib->super() == super, "siblings should have same superklass");
4249 }
4250
4251 // Verify local interfaces
4252 if (local_interfaces()) {
4253 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
4254 for (int j = 0; j < local_interfaces->length(); j++) {
4255 InstanceKlass* e = local_interfaces->at(j);
4256 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
4257 }
4258 }
4259
4260 // Verify transitive interfaces
4261 if (transitive_interfaces() != nullptr) {
4262 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
4263 for (int j = 0; j < transitive_interfaces->length(); j++) {
4264 InstanceKlass* e = transitive_interfaces->at(j);
4265 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
4266 }
4267 }
4268
4269 // Verify methods
4270 if (methods() != nullptr) {
4271 Array<Method*>* methods = this->methods();
4272 for (int j = 0; j < methods->length(); j++) {
4273 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4274 }
4275 for (int j = 0; j < methods->length() - 1; j++) {
4276 Method* m1 = methods->at(j);
4277 Method* m2 = methods->at(j + 1);
4278 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4279 }
4280 }
4281
4282 // Verify method ordering
4283 if (method_ordering() != nullptr) {
4284 Array<int>* method_ordering = this->method_ordering();
4285 int length = method_ordering->length();
4286 if (JvmtiExport::can_maintain_original_method_order() ||
4287 ((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) {
4288 guarantee(length == methods()->length(), "invalid method ordering length");
4289 jlong sum = 0;
4290 for (int j = 0; j < length; j++) {
4291 int original_index = method_ordering->at(j);
4292 guarantee(original_index >= 0, "invalid method ordering index");
4293 guarantee(original_index < length, "invalid method ordering index");
4294 sum += original_index;
4295 }
4296 // Verify sum of indices 0,1,...,length-1
4297 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
4298 } else {
4299 guarantee(length == 0, "invalid method ordering length");
4300 }
4301 }
4302
4303 // Verify default methods
4304 if (default_methods() != nullptr) {
4305 Array<Method*>* methods = this->default_methods();
4306 for (int j = 0; j < methods->length(); j++) {
4307 guarantee(methods->at(j)->is_method(), "non-method in methods array");
4308 }
4309 for (int j = 0; j < methods->length() - 1; j++) {
4310 Method* m1 = methods->at(j);
4311 Method* m2 = methods->at(j + 1);
4312 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
4313 }
4314 }
4315
4316 // Verify JNI static field identifiers
4317 if (jni_ids() != nullptr) {
4318 jni_ids()->verify(this);
4319 }
4320
4321 // Verify other fields
4322 if (constants() != nullptr) {
4323 guarantee(constants()->is_constantPool(), "should be constant pool");
4324 }
4325 }
4326
4327 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
4328 Klass::oop_verify_on(obj, st);
4329 VerifyFieldClosure blk;
4330 obj->oop_iterate(&blk);
4331 }
4332
4333
4334 // JNIid class for jfieldIDs only
4335 // Note to reviewers:
4336 // These JNI functions are just moved over to column 1 and not changed
4337 // in the compressed oops workspace.
4338 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
4339 _holder = holder;
4340 _offset = offset;
4341 _next = next;
4342 debug_only(_is_static_field_id = false;)
4343 }
4344
4345
4346 JNIid* JNIid::find(int offset) {
4347 JNIid* current = this;
4348 while (current != nullptr) {
4349 if (current->offset() == offset) return current;
4350 current = current->next();
4351 }
4352 return nullptr;
4353 }
4354
4355 void JNIid::deallocate(JNIid* current) {
4356 while (current != nullptr) {
4357 JNIid* next = current->next();
4358 delete current;
4359 current = next;
4360 }
4361 }
4362
4363
4364 void JNIid::verify(Klass* holder) {
4365 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
4366 int end_field_offset;
4367 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
4368
4369 JNIid* current = this;
4370 while (current != nullptr) {
4371 guarantee(current->holder() == holder, "Invalid klass in JNIid");
4372 #ifdef ASSERT
4373 int o = current->offset();
4374 if (current->is_static_field_id()) {
4375 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
4376 }
4377 #endif
4378 current = current->next();
4379 }
4380 }
4381
4382 void InstanceKlass::set_init_state(ClassState state) {
4383 if (state > loaded) {
4384 assert_lock_strong(_init_monitor);
4385 }
4386 #ifdef ASSERT
4387 bool good_state = is_shared() ? (_init_state <= state)
4388 : (_init_state < state);
4389 bool link_failed = _init_state == being_linked && state == loaded;
4390 assert(good_state || state == allocated || link_failed, "illegal state transition");
4391 #endif
4392 assert(_init_thread == nullptr, "should be cleared before state change");
4393 Atomic::store(&_init_state, state);
4394 }
4395
4396 #if INCLUDE_JVMTI
4397
4398 // RedefineClasses() support for previous versions
4399
4400 // Globally, there is at least one previous version of a class to walk
4401 // during class unloading, which is saved because old methods in the class
4402 // are still running. Otherwise the previous version list is cleaned up.
4403 bool InstanceKlass::_should_clean_previous_versions = false;
4404
4405 // Returns true if there are previous versions of a class for class
4406 // unloading only. Also resets the flag to false. purge_previous_version
4407 // will set the flag to true if there are any left, i.e., if there's any
4408 // work to do for next time. This is to avoid the expensive code cache
4409 // walk in CLDG::clean_deallocate_lists().
4410 bool InstanceKlass::should_clean_previous_versions_and_reset() {
4411 bool ret = _should_clean_previous_versions;
4412 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
4413 ret ? "true" : "false");
4414 _should_clean_previous_versions = false;
4415 return ret;
4416 }
4417
4418 // Purge previous versions before adding new previous versions of the class and
4419 // during class unloading.
4420 void InstanceKlass::purge_previous_version_list() {
4421 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
4422 assert(has_been_redefined(), "Should only be called for main class");
4423
4424 // Quick exit.
4425 if (previous_versions() == nullptr) {
4426 return;
4427 }
4428
4429 // This klass has previous versions so see what we can cleanup
4430 // while it is safe to do so.
4431
4432 int deleted_count = 0; // leave debugging breadcrumbs
4433 int live_count = 0;
4434 ClassLoaderData* loader_data = class_loader_data();
4435 assert(loader_data != nullptr, "should never be null");
4436
4437 ResourceMark rm;
4438 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
4439
4440 // previous versions are linked together through the InstanceKlass
4441 InstanceKlass* pv_node = previous_versions();
4442 InstanceKlass* last = this;
4443 int version = 0;
4444
4445 // check the previous versions list
4446 for (; pv_node != nullptr; ) {
4447
4448 ConstantPool* pvcp = pv_node->constants();
4449 assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
4450
4451 if (!pvcp->on_stack()) {
4452 // If the constant pool isn't on stack, none of the methods
4453 // are executing. Unlink this previous_version.
4454 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
4455 // so will be deallocated during the next phase of class unloading.
4456 log_trace(redefine, class, iklass, purge)
4457 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
4458 // Unlink from previous version list.
4459 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
4460 InstanceKlass* next = pv_node->previous_versions();
4461 pv_node->link_previous_versions(nullptr); // point next to null
4462 last->link_previous_versions(next);
4463 // Delete this node directly. Nothing is referring to it and we don't
4464 // want it to increase the counter for metadata to delete in CLDG.
4465 MetadataFactory::free_metadata(loader_data, pv_node);
4466 pv_node = next;
4467 deleted_count++;
4468 version++;
4469 continue;
4470 } else {
4471 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
4472 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
4473 live_count++;
4474 if (pvcp->is_shared()) {
4475 // Shared previous versions can never be removed so no cleaning is needed.
4476 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
4477 } else {
4478 // Previous version alive, set that clean is needed for next time.
4479 _should_clean_previous_versions = true;
4480 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
4481 }
4482 }
4483
4484 // next previous version
4485 last = pv_node;
4486 pv_node = pv_node->previous_versions();
4487 version++;
4488 }
4489 log_trace(redefine, class, iklass, purge)
4490 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4491 }
4492
4493 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4494 int emcp_method_count) {
4495 int obsolete_method_count = old_methods->length() - emcp_method_count;
4496
4497 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4498 _previous_versions != nullptr) {
4499 // We have a mix of obsolete and EMCP methods so we have to
4500 // clear out any matching EMCP method entries the hard way.
4501 int local_count = 0;
4502 for (int i = 0; i < old_methods->length(); i++) {
4503 Method* old_method = old_methods->at(i);
4504 if (old_method->is_obsolete()) {
4505 // only obsolete methods are interesting
4506 Symbol* m_name = old_method->name();
4507 Symbol* m_signature = old_method->signature();
4508
4509 // previous versions are linked together through the InstanceKlass
4510 int j = 0;
4511 for (InstanceKlass* prev_version = _previous_versions;
4512 prev_version != nullptr;
4513 prev_version = prev_version->previous_versions(), j++) {
4514
4515 Array<Method*>* method_refs = prev_version->methods();
4516 for (int k = 0; k < method_refs->length(); k++) {
4517 Method* method = method_refs->at(k);
4518
4519 if (!method->is_obsolete() &&
4520 method->name() == m_name &&
4521 method->signature() == m_signature) {
4522 // The current RedefineClasses() call has made all EMCP
4523 // versions of this method obsolete so mark it as obsolete
4524 log_trace(redefine, class, iklass, add)
4525 ("%s(%s): flush obsolete method @%d in version @%d",
4526 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4527
4528 method->set_is_obsolete();
4529 break;
4530 }
4531 }
4532
4533 // The previous loop may not find a matching EMCP method, but
4534 // that doesn't mean that we can optimize and not go any
4535 // further back in the PreviousVersion generations. The EMCP
4536 // method for this generation could have already been made obsolete,
4537 // but there still may be an older EMCP method that has not
4538 // been made obsolete.
4539 }
4540
4541 if (++local_count >= obsolete_method_count) {
4542 // no more obsolete methods so bail out now
4543 break;
4544 }
4545 }
4546 }
4547 }
4548 }
4549
4550 // Save the scratch_class as the previous version if any of the methods are running.
4551 // The previous_versions are used to set breakpoints in EMCP methods and they are
4552 // also used to clean MethodData links to redefined methods that are no longer running.
4553 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4554 int emcp_method_count) {
4555 assert(Thread::current()->is_VM_thread(),
4556 "only VMThread can add previous versions");
4557
4558 ResourceMark rm;
4559 log_trace(redefine, class, iklass, add)
4560 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4561
4562 // Clean out old previous versions for this class
4563 purge_previous_version_list();
4564
4565 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4566 // a previous redefinition may be made obsolete by this redefinition.
4567 Array<Method*>* old_methods = scratch_class->methods();
4568 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4569
4570 // If the constant pool for this previous version of the class
4571 // is not marked as being on the stack, then none of the methods
4572 // in this previous version of the class are on the stack so
4573 // we don't need to add this as a previous version.
4574 ConstantPool* cp_ref = scratch_class->constants();
4575 if (!cp_ref->on_stack()) {
4576 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4577 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4578 return;
4579 }
4580
4581 // Add previous version if any methods are still running or if this is
4582 // a shared class which should never be removed.
4583 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
4584 scratch_class->link_previous_versions(previous_versions());
4585 link_previous_versions(scratch_class);
4586 if (cp_ref->is_shared()) {
4587 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
4588 } else {
4589 // We only set clean_previous_versions flag for processing during class
4590 // unloading for non-shared classes.
4591 _should_clean_previous_versions = true;
4592 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4593 }
4594 } // end add_previous_version()
4595
4596 #endif // INCLUDE_JVMTI
4597
4598 Method* InstanceKlass::method_with_idnum(int idnum) {
4599 Method* m = nullptr;
4600 if (idnum < methods()->length()) {
4601 m = methods()->at(idnum);
4602 }
4603 if (m == nullptr || m->method_idnum() != idnum) {
4604 for (int index = 0; index < methods()->length(); ++index) {
4605 m = methods()->at(index);
4606 if (m->method_idnum() == idnum) {
4607 return m;
4608 }
4609 }
4610 // None found, return null for the caller to handle.
4611 return nullptr;
4612 }
4613 return m;
4614 }
4615
4616
4617 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4618 if (idnum >= methods()->length()) {
4619 return nullptr;
4620 }
4621 Method* m = methods()->at(idnum);
4622 if (m != nullptr && m->orig_method_idnum() == idnum) {
4623 return m;
4624 }
4625 // Obsolete method idnum does not match the original idnum
4626 for (int index = 0; index < methods()->length(); ++index) {
4627 m = methods()->at(index);
4628 if (m->orig_method_idnum() == idnum) {
4629 return m;
4630 }
4631 }
4632 // None found, return null for the caller to handle.
4633 return nullptr;
4634 }
4635
4636
4637 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4638 InstanceKlass* holder = get_klass_version(version);
4639 if (holder == nullptr) {
4640 return nullptr; // The version of klass is gone, no method is found
4641 }
4642 Method* method = holder->method_with_orig_idnum(idnum);
4643 return method;
4644 }
4645
4646 #if INCLUDE_JVMTI
4647 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4648 return _cached_class_file;
4649 }
4650
4651 jint InstanceKlass::get_cached_class_file_len() {
4652 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4653 }
4654
4655 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4656 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4657 }
4658 #endif
4659
4660 // Make a step iterating over the class hierarchy under the root class.
4661 // Skips subclasses if requested.
4662 void ClassHierarchyIterator::next() {
4663 assert(_current != nullptr, "required");
4664 if (_visit_subclasses && _current->subklass() != nullptr) {
4665 _current = _current->subklass();
4666 return; // visit next subclass
4667 }
4668 _visit_subclasses = true; // reset
4669 while (_current->next_sibling() == nullptr && _current != _root) {
4670 _current = _current->superklass(); // backtrack; no more sibling subclasses left
4671 }
4672 if (_current == _root) {
4673 // Iteration is over (back at root after backtracking). Invalidate the iterator.
4674 _current = nullptr;
4675 return;
4676 }
4677 _current = _current->next_sibling();
4678 return; // visit next sibling subclass
4679 }
4680