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