1 /*
2 * Copyright (c) 1997, 2018, 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 "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/javaClasses.hpp"
32 #include "classfile/moduleEntry.hpp"
33 #include "classfile/systemDictionary.hpp"
34 #include "classfile/systemDictionaryShared.hpp"
35 #include "classfile/verifier.hpp"
36 #include "classfile/vmSymbols.hpp"
37 #include "code/dependencyContext.hpp"
38 #include "compiler/compileBroker.hpp"
39 #include "gc/shared/collectedHeap.inline.hpp"
40 #include "gc/shared/specialized_oop_closures.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "interpreter/rewriter.hpp"
43 #include "jvmtifiles/jvmti.h"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/heapInspection.hpp"
48 #include "memory/iterator.inline.hpp"
49 #include "memory/metadataFactory.hpp"
50 #include "memory/metaspaceClosure.hpp"
51 #include "memory/metaspaceShared.hpp"
52 #include "memory/oopFactory.hpp"
53 #include "memory/resourceArea.hpp"
54 #include "oops/fieldStreams.hpp"
55 #include "oops/instanceClassLoaderKlass.hpp"
56 #include "oops/instanceKlass.inline.hpp"
57 #include "oops/instanceMirrorKlass.hpp"
58 #include "oops/instanceOop.hpp"
59 #include "oops/klass.inline.hpp"
60 #include "oops/method.hpp"
61 #include "oops/oop.inline.hpp"
62 #include "oops/symbol.hpp"
63 #include "oops/valueKlass.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "prims/jvmtiRedefineClasses.hpp"
66 #include "prims/jvmtiThreadState.hpp"
67 #include "prims/methodComparator.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/fieldDescriptor.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/javaCalls.hpp"
72 #include "runtime/mutexLocker.hpp"
73 #include "runtime/orderAccess.inline.hpp"
74 #include "runtime/thread.inline.hpp"
75 #include "services/classLoadingService.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/dtrace.hpp"
78 #include "utilities/macros.hpp"
79 #include "utilities/stringUtils.hpp"
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83
84 #ifdef DTRACE_ENABLED
85
86
87 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
88 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
89 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
90 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
91 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
92 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
93 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
94 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
95 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
96 { \
97 char* data = NULL; \
98 int len = 0; \
99 Symbol* clss_name = name(); \
100 if (clss_name != NULL) { \
101 data = (char*)clss_name->bytes(); \
102 len = clss_name->utf8_length(); \
103 } \
104 HOTSPOT_CLASS_INITIALIZATION_##type( \
105 data, len, (void*)class_loader(), thread_type); \
106 }
107
108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
109 { \
110 char* data = NULL; \
111 int len = 0; \
112 Symbol* clss_name = name(); \
113 if (clss_name != NULL) { \
114 data = (char*)clss_name->bytes(); \
115 len = clss_name->utf8_length(); \
116 } \
117 HOTSPOT_CLASS_INITIALIZATION_##type( \
118 data, len, (void*)class_loader(), thread_type, wait); \
119 }
120
121 #else // ndef DTRACE_ENABLED
122
123 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
125
126 #endif // ndef DTRACE_ENABLED
127
128 volatile int InstanceKlass::_total_instanceKlass_count = 0;
129
130 static inline bool is_class_loader(const Symbol* class_name,
131 const ClassFileParser& parser) {
132 assert(class_name != NULL, "invariant");
133
134 if (class_name == vmSymbols::java_lang_ClassLoader()) {
135 return true;
136 }
137
138 if (SystemDictionary::ClassLoader_klass_loaded()) {
139 const Klass* const super_klass = parser.super_klass();
140 if (super_klass != NULL) {
141 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
142 return true;
143 }
144 }
145 }
146 return false;
147 }
148
149 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
150 const int size = InstanceKlass::size(parser.vtable_size(),
151 parser.itable_size(),
152 nonstatic_oop_map_size(parser.total_oop_map_count()),
153 parser.is_interface(),
154 parser.is_anonymous(),
155 should_store_fingerprint(parser.is_anonymous()),
156 parser.has_flattenable_fields() ? parser.java_fields_count() : 0,
157 parser.is_value_type());
158
159 const Symbol* const class_name = parser.class_name();
160 assert(class_name != NULL, "invariant");
161 ClassLoaderData* loader_data = parser.loader_data();
162 assert(loader_data != NULL, "invariant");
163
164 InstanceKlass* ik;
165
166 // Allocation
167 if (REF_NONE == parser.reference_type()) {
168 if (class_name == vmSymbols::java_lang_Class()) {
169 // mirror
170 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
171 } else if (is_class_loader(class_name, parser)) {
172 // class loader
173 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
174 } else if (parser.is_value_type()) {
175 // value type
176 ik = new (loader_data, size, THREAD) ValueKlass(parser);
177 } else {
178 // normal
179 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
180 }
181 } else {
182 // reference
183 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
184 }
185
186 // Check for pending exception before adding to the loader data and incrementing
187 // class count. Can get OOM here.
188 if (HAS_PENDING_EXCEPTION) {
189 return NULL;
190 }
191
192 assert(ik != NULL, "invariant");
193
194 const bool publicize = !parser.is_internal();
195 #ifdef ASSERT
196 assert(ik->size() == size, "");
197 ik->bounds_check((address) ik->start_of_vtable(), false, size);
198 ik->bounds_check((address) ik->start_of_itable(), false, size);
199 ik->bounds_check((address) ik->end_of_itable(), true, size);
200 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
201 #endif //ASSERT
202
203 // Add all classes to our internal class loader list here,
204 // including classes in the bootstrap (NULL) class loader.
205 loader_data->add_class(ik, publicize);
206 Atomic::inc(&_total_instanceKlass_count);
207
208 return ik;
209 }
210
211 #ifndef PRODUCT
212 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
213 const char* bad = NULL;
214 address end = NULL;
215 if (addr < (address)this) {
216 bad = "before";
217 } else if (addr == (address)this) {
218 if (edge_ok) return true;
219 bad = "just before";
220 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
221 if (edge_ok) return true;
222 bad = "just after";
223 } else if (addr > end) {
224 bad = "after";
225 } else {
226 return true;
227 }
228 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
229 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
230 Verbose = WizardMode = true; this->print(); //@@
231 return false;
232 }
233 #endif //PRODUCT
234
235 // copy method ordering from resource area to Metaspace
236 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
237 if (m != NULL) {
238 // allocate a new array and copy contents (memcpy?)
239 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
240 for (int i = 0; i < m->length(); i++) {
241 _method_ordering->at_put(i, m->at(i));
242 }
243 } else {
244 _method_ordering = Universe::the_empty_int_array();
245 }
246 }
247
248 // create a new array of vtable_indices for default methods
249 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
250 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
251 assert(default_vtable_indices() == NULL, "only create once");
252 set_default_vtable_indices(vtable_indices);
253 return vtable_indices;
254 }
255
256 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
257 _static_field_size(parser.static_field_size()),
258 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
259 _itable_len(parser.itable_size()),
260 _reference_type(parser.reference_type()),
261 _extra_flags(0),
262 _adr_valueklass_fixed_block(NULL) {
263 set_vtable_length(parser.vtable_size());
264 set_kind(kind);
265 set_access_flags(parser.access_flags());
266 set_is_anonymous(parser.is_anonymous());
267 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
268 false));
269 if (parser.has_flattenable_fields()) {
270 set_has_value_fields();
271 }
272 _java_fields_count = parser.java_fields_count();
273
274 assert(NULL == _methods, "underlying memory not zeroed?");
275 assert(is_instance_klass(), "is layout incorrect?");
276 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
277 }
278
279 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
280 Array<Method*>* methods) {
281 if (methods != NULL && methods != Universe::the_empty_method_array() &&
282 !methods->is_shared()) {
283 for (int i = 0; i < methods->length(); i++) {
284 Method* method = methods->at(i);
285 if (method == NULL) continue; // maybe null if error processing
286 // Only want to delete methods that are not executing for RedefineClasses.
287 // The previous version will point to them so they're not totally dangling
288 assert (!method->on_stack(), "shouldn't be called with methods on stack");
289 MetadataFactory::free_metadata(loader_data, method);
290 }
291 MetadataFactory::free_array<Method*>(loader_data, methods);
292 }
293 }
294
295 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
296 const Klass* super_klass,
297 Array<Klass*>* local_interfaces,
298 Array<Klass*>* transitive_interfaces) {
299 // Only deallocate transitive interfaces if not empty, same as super class
300 // or same as local interfaces. See code in parseClassFile.
301 Array<Klass*>* ti = transitive_interfaces;
302 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
303 // check that the interfaces don't come from super class
304 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
305 InstanceKlass::cast(super_klass)->transitive_interfaces();
306 if (ti != sti && ti != NULL && !ti->is_shared()) {
307 MetadataFactory::free_array<Klass*>(loader_data, ti);
308 }
309 }
310
311 // local interfaces can be empty
312 if (local_interfaces != Universe::the_empty_klass_array() &&
313 local_interfaces != NULL && !local_interfaces->is_shared()) {
314 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
315 }
316 }
317
318 // This function deallocates the metadata and C heap pointers that the
319 // InstanceKlass points to.
320 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
321
322 // Orphan the mirror first, CMS thinks it's still live.
323 if (java_mirror() != NULL) {
324 java_lang_Class::set_klass(java_mirror(), NULL);
325 }
326
327 // Also remove mirror from handles
328 loader_data->remove_handle(_java_mirror);
329
330 // Need to take this class off the class loader data list.
331 loader_data->remove_class(this);
332
333 // The array_klass for this class is created later, after error handling.
334 // For class redefinition, we keep the original class so this scratch class
335 // doesn't have an array class. Either way, assert that there is nothing
336 // to deallocate.
337 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
338
339 // Release C heap allocated data that this might point to, which includes
340 // reference counting symbol names.
341 release_C_heap_structures();
342
343 deallocate_methods(loader_data, methods());
344 set_methods(NULL);
345
346 if (method_ordering() != NULL &&
347 method_ordering() != Universe::the_empty_int_array() &&
348 !method_ordering()->is_shared()) {
349 MetadataFactory::free_array<int>(loader_data, method_ordering());
350 }
351 set_method_ordering(NULL);
352
353 // default methods can be empty
354 if (default_methods() != NULL &&
355 default_methods() != Universe::the_empty_method_array() &&
356 !default_methods()->is_shared()) {
357 MetadataFactory::free_array<Method*>(loader_data, default_methods());
358 }
359 // Do NOT deallocate the default methods, they are owned by superinterfaces.
360 set_default_methods(NULL);
361
362 // default methods vtable indices can be empty
363 if (default_vtable_indices() != NULL &&
364 !default_vtable_indices()->is_shared()) {
365 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
366 }
367 set_default_vtable_indices(NULL);
368
369
370 // This array is in Klass, but remove it with the InstanceKlass since
371 // this place would be the only caller and it can share memory with transitive
372 // interfaces.
373 if (secondary_supers() != NULL &&
374 secondary_supers() != Universe::the_empty_klass_array() &&
375 secondary_supers() != transitive_interfaces() &&
376 !secondary_supers()->is_shared()) {
377 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
378 }
379 set_secondary_supers(NULL);
380
381 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
382 set_transitive_interfaces(NULL);
383 set_local_interfaces(NULL);
384
385 if (fields() != NULL && !fields()->is_shared()) {
386 MetadataFactory::free_array<jushort>(loader_data, fields());
387 }
388 set_fields(NULL, 0);
389
390 // If a method from a redefined class is using this constant pool, don't
391 // delete it, yet. The new class's previous version will point to this.
392 if (constants() != NULL) {
393 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
394 if (!constants()->is_shared()) {
395 MetadataFactory::free_metadata(loader_data, constants());
396 }
397 // Delete any cached resolution errors for the constant pool
398 SystemDictionary::delete_resolution_error(constants());
399
400 set_constants(NULL);
401 }
402
403 if (inner_classes() != NULL &&
404 inner_classes() != Universe::the_empty_short_array() &&
405 !inner_classes()->is_shared()) {
406 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
407 }
408 set_inner_classes(NULL);
409
410 // We should deallocate the Annotations instance if it's not in shared spaces.
411 if (annotations() != NULL && !annotations()->is_shared()) {
412 MetadataFactory::free_metadata(loader_data, annotations());
413 }
414 set_annotations(NULL);
415 }
416
417 bool InstanceKlass::should_be_initialized() const {
418 return !is_initialized();
419 }
420
421 klassItable InstanceKlass::itable() const {
422 return klassItable(const_cast<InstanceKlass*>(this));
423 }
424
425 void InstanceKlass::eager_initialize(Thread *thread) {
426 if (!EagerInitialization) return;
427
428 if (this->is_not_initialized()) {
429 // abort if the the class has a class initializer
430 if (this->class_initializer() != NULL) return;
431
432 // abort if it is java.lang.Object (initialization is handled in genesis)
433 Klass* super_klass = super();
434 if (super_klass == NULL) return;
435
436 // abort if the super class should be initialized
437 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
438
439 // call body to expose the this pointer
440 eager_initialize_impl();
441 }
442 }
443
444 // JVMTI spec thinks there are signers and protection domain in the
445 // instanceKlass. These accessors pretend these fields are there.
446 // The hprof specification also thinks these fields are in InstanceKlass.
447 oop InstanceKlass::protection_domain() const {
448 // return the protection_domain from the mirror
449 return java_lang_Class::protection_domain(java_mirror());
450 }
451
452 // To remove these from requires an incompatible change and CCC request.
453 objArrayOop InstanceKlass::signers() const {
454 // return the signers from the mirror
455 return java_lang_Class::signers(java_mirror());
456 }
457
458 oop InstanceKlass::init_lock() const {
459 // return the init lock from the mirror
460 oop lock = java_lang_Class::init_lock(java_mirror());
461 // Prevent reordering with any access of initialization state
462 OrderAccess::loadload();
463 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
464 "only fully initialized state can have a null lock");
465 return lock;
466 }
467
468 // Set the initialization lock to null so the object can be GC'ed. Any racing
469 // threads to get this lock will see a null lock and will not lock.
470 // That's okay because they all check for initialized state after getting
471 // the lock and return.
472 void InstanceKlass::fence_and_clear_init_lock() {
473 // make sure previous stores are all done, notably the init_state.
474 OrderAccess::storestore();
475 java_lang_Class::set_init_lock(java_mirror(), NULL);
476 assert(!is_not_initialized(), "class must be initialized now");
477 }
478
479 void InstanceKlass::eager_initialize_impl() {
480 EXCEPTION_MARK;
481 HandleMark hm(THREAD);
482 Handle h_init_lock(THREAD, init_lock());
483 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
484
485 // abort if someone beat us to the initialization
486 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
487
488 ClassState old_state = init_state();
489 link_class_impl(true, THREAD);
490 if (HAS_PENDING_EXCEPTION) {
491 CLEAR_PENDING_EXCEPTION;
492 // Abort if linking the class throws an exception.
493
494 // Use a test to avoid redundantly resetting the state if there's
495 // no change. Set_init_state() asserts that state changes make
496 // progress, whereas here we might just be spinning in place.
497 if (old_state != _init_state)
498 set_init_state(old_state);
499 } else {
500 // linking successfull, mark class as initialized
501 set_init_state(fully_initialized);
502 fence_and_clear_init_lock();
503 // trace
504 if (log_is_enabled(Info, class, init)) {
505 ResourceMark rm(THREAD);
506 log_info(class, init)("[Initialized %s without side effects]", external_name());
507 }
508 }
509 }
510
511
512 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
513 // process. The step comments refers to the procedure described in that section.
514 // Note: implementation moved to static method to expose the this pointer.
515 void InstanceKlass::initialize(TRAPS) {
516 if (this->should_be_initialized()) {
517 initialize_impl(CHECK);
518 // Note: at this point the class may be initialized
519 // OR it may be in the state of being initialized
520 // in case of recursive initialization!
521 } else {
522 assert(is_initialized(), "sanity check");
523 }
524 }
525
526
527 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
528 // 1) Verify the bytecodes
529 Verifier::Mode mode =
530 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
531 return Verifier::verify(this, mode, should_verify_class(), THREAD);
532 }
533
534
535 // Used exclusively by the shared spaces dump mechanism to prevent
536 // classes mapped into the shared regions in new VMs from appearing linked.
537
538 void InstanceKlass::unlink_class() {
539 assert(is_linked(), "must be linked");
540 _init_state = loaded;
541 }
542
543 void InstanceKlass::link_class(TRAPS) {
544 assert(is_loaded(), "must be loaded");
545 if (!is_linked()) {
546 link_class_impl(true, CHECK);
547 }
548 }
549
550 // Called to verify that a class can link during initialization, without
551 // throwing a VerifyError.
552 bool InstanceKlass::link_class_or_fail(TRAPS) {
553 assert(is_loaded(), "must be loaded");
554 if (!is_linked()) {
555 link_class_impl(false, CHECK_false);
556 }
557 return is_linked();
558 }
559
560 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
561 if (DumpSharedSpaces && is_in_error_state()) {
562 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
563 // the class has failed verification. Throwing the NoClassDefFoundError here is just
564 // a convenient way to stop repeat attempts to verify the same (bad) class.
565 //
566 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
567 // if we are executing Java code. This is not a problem for CDS dumping phase since
568 // it doesn't execute any Java code.
569 ResourceMark rm(THREAD);
570 Exceptions::fthrow(THREAD_AND_LOCATION,
571 vmSymbols::java_lang_NoClassDefFoundError(),
572 "Class %s, or one of its supertypes, failed class initialization",
573 external_name());
574 return false;
575 }
576 // return if already verified
577 if (is_linked()) {
578 return true;
579 }
580
581 // Timing
582 // timer handles recursion
583 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
584 JavaThread* jt = (JavaThread*)THREAD;
585
586 // link super class before linking this class
587 Klass* super_klass = super();
588 if (super_klass != NULL) {
589 if (super_klass->is_interface()) { // check if super class is an interface
590 ResourceMark rm(THREAD);
591 Exceptions::fthrow(
592 THREAD_AND_LOCATION,
593 vmSymbols::java_lang_IncompatibleClassChangeError(),
594 "class %s has interface %s as super class",
595 external_name(),
596 super_klass->external_name()
597 );
598 return false;
599 }
600
601 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
602 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
603 }
604
605 // link all interfaces implemented by this class before linking this class
606 Array<Klass*>* interfaces = local_interfaces();
607 int num_interfaces = interfaces->length();
608 for (int index = 0; index < num_interfaces; index++) {
609 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
610 interk->link_class_impl(throw_verifyerror, CHECK_false);
611 }
612
613 // If a value type is referenced by a class (either as a field type or a
614 // method argument or return type) this value type must be loaded during
615 // the linking of this class because size and properties of the value type
616 // must be known in order to be able to perform value type optimizations
617
618 // Note: circular dependencies between value types are not handled yet
619
620 // Note: one case is not handled yet: arrays of value types => FixMe
621
622 // Note: the current implementation is not optimized because the search for
623 // value types is performed on all classes. It would be more efficient to
624 // detect value types during verification and 'tag' the classes for which
625 // value type loading is required. However, this optimization won't be
626 // applicable to classes that are not verified
627
628 // First step: fields
629 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
630 ResourceMark rm(THREAD);
631 if (fs.field_descriptor().access_flags().is_flattenable()) {
632 Symbol* signature = fs.field_descriptor().signature();
633 // Get current loader and protection domain first.
634 oop loader = class_loader();
635 oop prot_domain = protection_domain();
636 Klass* klass = SystemDictionary::resolve_or_fail(signature,
637 Handle(THREAD, loader), Handle(THREAD, prot_domain), true,
638 THREAD);
639 if (klass == NULL) {
640 THROW_(vmSymbols::java_lang_LinkageError(), false);
641 }
642 }
643 }
644
645 // Second step: methods arguments and return types
646 // for (int i = 0; i < this_k->constants()->length(); i++) {
647 // if (this_k->constants()->tag_at(i).is_method()) {
648 // Symbol* signature = this_k->constants()->signature_ref_at(i);
649 // ResourceMark rm(THREAD);
650 // for (SignatureStream ss(signature); !ss.is_done(); ss.next()) {
651 // if (ss.type() == T_VALUETYPE) {
652 // Symbol* sig = ss.as_symbol(THREAD);
653 // // Get current loader and protection domain first.
654 // oop loader = this_k->class_loader();
655 // oop protection_domain = this_k->protection_domain();
656 //
657 // bool ok = SystemDictionary::resolve_or_fail(sig,
658 // Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
659 // THREAD);
660 // if (!ok) {
661 // THROW_(vmSymbols::java_lang_LinkageError(), false);
662 // }
663 // }
664 // }
665 // }
666 // }
667
668 // in case the class is linked in the process of linking its superclasses
669 if (is_linked()) {
670 return true;
671 }
672
673 // trace only the link time for this klass that includes
674 // the verification time
675 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
676 ClassLoader::perf_class_link_selftime(),
677 ClassLoader::perf_classes_linked(),
678 jt->get_thread_stat()->perf_recursion_counts_addr(),
679 jt->get_thread_stat()->perf_timers_addr(),
680 PerfClassTraceTime::CLASS_LINK);
681
682 // verification & rewriting
683 {
684 HandleMark hm(THREAD);
685 Handle h_init_lock(THREAD, init_lock());
686 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
687 // rewritten will have been set if loader constraint error found
688 // on an earlier link attempt
689 // don't verify or rewrite if already rewritten
690 //
691
692 if (!is_linked()) {
693 if (!is_rewritten()) {
694 {
695 bool verify_ok = verify_code(throw_verifyerror, THREAD);
696 if (!verify_ok) {
697 return false;
698 }
699 }
700
701 // Just in case a side-effect of verify linked this class already
702 // (which can sometimes happen since the verifier loads classes
703 // using custom class loaders, which are free to initialize things)
704 if (is_linked()) {
705 return true;
706 }
707
708 // also sets rewritten
709 rewrite_class(CHECK_false);
710 } else if (is_shared()) {
711 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
712 }
713
714 // relocate jsrs and link methods after they are all rewritten
715 link_methods(CHECK_false);
716
717 // Initialize the vtable and interface table after
718 // methods have been rewritten since rewrite may
719 // fabricate new Method*s.
720 // also does loader constraint checking
721 //
722 // initialize_vtable and initialize_itable need to be rerun for
723 // a shared class if the class is not loaded by the NULL classloader.
724 ClassLoaderData * loader_data = class_loader_data();
725 if (!(is_shared() &&
726 loader_data->is_the_null_class_loader_data())) {
727 ResourceMark rm(THREAD);
728 vtable().initialize_vtable(true, CHECK_false);
729 itable().initialize_itable(true, CHECK_false);
730 }
731 #ifdef ASSERT
732 else {
733 vtable().verify(tty, true);
734 // In case itable verification is ever added.
735 // itable().verify(tty, true);
736 }
737 #endif
738
739 set_init_state(linked);
740 if (JvmtiExport::should_post_class_prepare()) {
741 Thread *thread = THREAD;
742 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
743 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
744 }
745 }
746 }
747 return true;
748 }
749
750
751 // Rewrite the byte codes of all of the methods of a class.
752 // The rewriter must be called exactly once. Rewriting must happen after
753 // verification but before the first method of the class is executed.
754 void InstanceKlass::rewrite_class(TRAPS) {
755 assert(is_loaded(), "must be loaded");
756 if (is_rewritten()) {
757 assert(is_shared(), "rewriting an unshared class?");
758 return;
759 }
760 Rewriter::rewrite(this, CHECK);
761 set_rewritten();
762 }
763
764 // Now relocate and link method entry points after class is rewritten.
765 // This is outside is_rewritten flag. In case of an exception, it can be
766 // executed more than once.
767 void InstanceKlass::link_methods(TRAPS) {
768 int len = methods()->length();
769 for (int i = len-1; i >= 0; i--) {
770 methodHandle m(THREAD, methods()->at(i));
771
772 // Set up method entry points for compiler and interpreter .
773 m->link_method(m, CHECK);
774 }
775 }
776
777 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
778 void InstanceKlass::initialize_super_interfaces(TRAPS) {
779 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
780 for (int i = 0; i < local_interfaces()->length(); ++i) {
781 Klass* iface = local_interfaces()->at(i);
782 InstanceKlass* ik = InstanceKlass::cast(iface);
783
784 // Initialization is depth first search ie. we start with top of the inheritance tree
785 // has_nonstatic_concrete_methods drives searching superinterfaces since it
786 // means has_nonstatic_concrete_methods in its superinterface hierarchy
787 if (ik->has_nonstatic_concrete_methods()) {
788 ik->initialize_super_interfaces(CHECK);
789 }
790
791 // Only initialize() interfaces that "declare" concrete methods.
792 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
793 ik->initialize(CHECK);
794 }
795 }
796 }
797
798 void InstanceKlass::initialize_impl(TRAPS) {
799 HandleMark hm(THREAD);
800
801 // Make sure klass is linked (verified) before initialization
802 // A class could already be verified, since it has been reflected upon.
803 link_class(CHECK);
804
805 DTRACE_CLASSINIT_PROBE(required, -1);
806
807 bool wait = false;
808
809 // refer to the JVM book page 47 for description of steps
810 // Step 1
811 {
812 Handle h_init_lock(THREAD, init_lock());
813 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
814
815 Thread *self = THREAD; // it's passed the current thread
816
817 // Step 2
818 // If we were to use wait() instead of waitInterruptibly() then
819 // we might end up throwing IE from link/symbol resolution sites
820 // that aren't expected to throw. This would wreak havoc. See 6320309.
821 while(is_being_initialized() && !is_reentrant_initialization(self)) {
822 wait = true;
823 ol.waitUninterruptibly(CHECK);
824 }
825
826 // Step 3
827 if (is_being_initialized() && is_reentrant_initialization(self)) {
828 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
829 return;
830 }
831
832 // Step 4
833 if (is_initialized()) {
834 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
835 return;
836 }
837
838 // Step 5
839 if (is_in_error_state()) {
840 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
841 ResourceMark rm(THREAD);
842 const char* desc = "Could not initialize class ";
843 const char* className = external_name();
844 size_t msglen = strlen(desc) + strlen(className) + 1;
845 char* message = NEW_RESOURCE_ARRAY(char, msglen);
846 if (NULL == message) {
847 // Out of memory: can't create detailed error message
848 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
849 } else {
850 jio_snprintf(message, msglen, "%s%s", desc, className);
851 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
852 }
853 }
854
855 // Step 6
856 set_init_state(being_initialized);
857 set_init_thread(self);
858 }
859
860 // Step 7
861 // Next, if C is a class rather than an interface, initialize it's super class and super
862 // interfaces.
863 if (!is_interface()) {
864 Klass* super_klass = super();
865 if (super_klass != NULL && super_klass->should_be_initialized()) {
866 super_klass->initialize(THREAD);
867 }
868 // If C implements any interface that declares a non-static, concrete method,
869 // the initialization of C triggers initialization of its super interfaces.
870 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
871 // having a superinterface that declares, non-static, concrete methods
872 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
873 initialize_super_interfaces(THREAD);
874 }
875
876 // If any exceptions, complete abruptly, throwing the same exception as above.
877 if (HAS_PENDING_EXCEPTION) {
878 Handle e(THREAD, PENDING_EXCEPTION);
879 CLEAR_PENDING_EXCEPTION;
880 {
881 EXCEPTION_MARK;
882 // Locks object, set state, and notify all waiting threads
883 set_initialization_state_and_notify(initialization_error, THREAD);
884 CLEAR_PENDING_EXCEPTION;
885 }
886 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
887 THROW_OOP(e());
888 }
889 }
890
891 // Step 8
892 // Initialize classes of flattenable fields
893 {
894 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
895 if (fs.is_flattenable()) {
896 InstanceKlass* field_klass = InstanceKlass::cast(this->get_value_field_klass(fs.index()));
897 field_klass->initialize(CHECK);
898 }
899 }
900 }
901
902
903 // Look for aot compiled methods for this klass, including class initializer.
904 AOTLoader::load_for_klass(this, THREAD);
905
906 // Step 9
907 {
908 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
909 JavaThread* jt = (JavaThread*)THREAD;
910 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
911 // Timer includes any side effects of class initialization (resolution,
912 // etc), but not recursive entry into call_class_initializer().
913 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
914 ClassLoader::perf_class_init_selftime(),
915 ClassLoader::perf_classes_inited(),
916 jt->get_thread_stat()->perf_recursion_counts_addr(),
917 jt->get_thread_stat()->perf_timers_addr(),
918 PerfClassTraceTime::CLASS_CLINIT);
919 call_class_initializer(THREAD);
920 }
921
922 // Step 10
923 if (!HAS_PENDING_EXCEPTION) {
924 set_initialization_state_and_notify(fully_initialized, CHECK);
925 {
926 debug_only(vtable().verify(tty, true);)
927 }
928 }
929 else {
930 // Step 11 and 12
931 Handle e(THREAD, PENDING_EXCEPTION);
932 CLEAR_PENDING_EXCEPTION;
933 // JVMTI has already reported the pending exception
934 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
935 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
936 {
937 EXCEPTION_MARK;
938 set_initialization_state_and_notify(initialization_error, THREAD);
939 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
940 // JVMTI has already reported the pending exception
941 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
942 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
943 }
944 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
945 if (e->is_a(SystemDictionary::Error_klass())) {
946 THROW_OOP(e());
947 } else {
948 JavaCallArguments args(e);
949 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
950 vmSymbols::throwable_void_signature(),
951 &args);
952 }
953 }
954 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
955 }
956
957
958 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
959 Handle h_init_lock(THREAD, init_lock());
960 if (h_init_lock() != NULL) {
961 ObjectLocker ol(h_init_lock, THREAD);
962 set_init_state(state);
963 fence_and_clear_init_lock();
964 ol.notify_all(CHECK);
965 } else {
966 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
967 set_init_state(state);
968 }
969 }
970
971 // The embedded _implementor field can only record one implementor.
972 // When there are more than one implementors, the _implementor field
973 // is set to the interface Klass* itself. Following are the possible
974 // values for the _implementor field:
975 // NULL - no implementor
976 // implementor Klass* - one implementor
977 // self - more than one implementor
978 //
979 // The _implementor field only exists for interfaces.
980 void InstanceKlass::add_implementor(Klass* k) {
981 assert(Compile_lock->owned_by_self(), "");
982 assert(is_interface(), "not interface");
983 // Filter out my subinterfaces.
984 // (Note: Interfaces are never on the subklass list.)
985 if (InstanceKlass::cast(k)->is_interface()) return;
986
987 // Filter out subclasses whose supers already implement me.
988 // (Note: CHA must walk subclasses of direct implementors
989 // in order to locate indirect implementors.)
990 Klass* sk = k->super();
991 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
992 // We only need to check one immediate superclass, since the
993 // implements_interface query looks at transitive_interfaces.
994 // Any supers of the super have the same (or fewer) transitive_interfaces.
995 return;
996
997 Klass* ik = implementor();
998 if (ik == NULL) {
999 set_implementor(k);
1000 } else if (ik != this) {
1001 // There is already an implementor. Use itself as an indicator of
1002 // more than one implementors.
1003 set_implementor(this);
1004 }
1005
1006 // The implementor also implements the transitive_interfaces
1007 for (int index = 0; index < local_interfaces()->length(); index++) {
1008 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1009 }
1010 }
1011
1012 void InstanceKlass::init_implementor() {
1013 if (is_interface()) {
1014 set_implementor(NULL);
1015 }
1016 }
1017
1018
1019 void InstanceKlass::process_interfaces(Thread *thread) {
1020 // link this class into the implementors list of every interface it implements
1021 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1022 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1023 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1024 assert(interf->is_interface(), "expected interface");
1025 interf->add_implementor(this);
1026 }
1027 }
1028
1029 bool InstanceKlass::can_be_primary_super_slow() const {
1030 if (is_interface())
1031 return false;
1032 else
1033 return Klass::can_be_primary_super_slow();
1034 }
1035
1036 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1037 // The secondaries are the implemented interfaces.
1038 Array<Klass*>* interfaces = transitive_interfaces();
1039 int num_secondaries = num_extra_slots + interfaces->length();
1040 if (num_secondaries == 0) {
1041 // Must share this for correct bootstrapping!
1042 set_secondary_supers(Universe::the_empty_klass_array());
1043 return NULL;
1044 } else if (num_extra_slots == 0) {
1045 // The secondary super list is exactly the same as the transitive interfaces.
1046 // Redefine classes has to be careful not to delete this!
1047 set_secondary_supers(interfaces);
1048 return NULL;
1049 } else {
1050 // Copy transitive interfaces to a temporary growable array to be constructed
1051 // into the secondary super list with extra slots.
1052 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1053 for (int i = 0; i < interfaces->length(); i++) {
1054 secondaries->push(interfaces->at(i));
1055 }
1056 return secondaries;
1057 }
1058 }
1059
1060 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1061 if (k->is_interface()) {
1062 return implements_interface(k);
1063 } else {
1064 return Klass::compute_is_subtype_of(k);
1065 }
1066 }
1067
1068 bool InstanceKlass::implements_interface(Klass* k) const {
1069 if (this == k) return true;
1070 assert(k->is_interface(), "should be an interface class");
1071 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1072 if (transitive_interfaces()->at(i) == k) {
1073 return true;
1074 }
1075 }
1076 return false;
1077 }
1078
1079 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1080 // Verify direct super interface
1081 if (this == k) return true;
1082 assert(k->is_interface(), "should be an interface class");
1083 for (int i = 0; i < local_interfaces()->length(); i++) {
1084 if (local_interfaces()->at(i) == k) {
1085 return true;
1086 }
1087 }
1088 return false;
1089 }
1090
1091 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1092 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1093 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1094 report_java_out_of_memory("Requested array size exceeds VM limit");
1095 JvmtiExport::post_array_size_exhausted();
1096 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1097 }
1098 int size = objArrayOopDesc::object_size(length);
1099 Klass* ak = array_klass(n, CHECK_NULL);
1100 objArrayOop o =
1101 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1102 return o;
1103 }
1104
1105 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1106 if (TraceFinalizerRegistration) {
1107 tty->print("Registered ");
1108 i->print_value_on(tty);
1109 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1110 }
1111 instanceHandle h_i(THREAD, i);
1112 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1113 JavaValue result(T_VOID);
1114 JavaCallArguments args(h_i);
1115 methodHandle mh (THREAD, Universe::finalizer_register_method());
1116 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1117 return h_i();
1118 }
1119
1120 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1121 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1122 int size = size_helper(); // Query before forming handle.
1123
1124 instanceOop i;
1125
1126 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1127 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1128 i = register_finalizer(i, CHECK_NULL);
1129 }
1130 return i;
1131 }
1132
1133 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1134 if (is_interface() || is_abstract()) {
1135 ResourceMark rm(THREAD);
1136 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1137 : vmSymbols::java_lang_InstantiationException(), external_name());
1138 }
1139 if (this == SystemDictionary::Class_klass()) {
1140 ResourceMark rm(THREAD);
1141 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1142 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1143 }
1144 }
1145
1146 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1147 // Need load-acquire for lock-free read
1148 if (array_klasses_acquire() == NULL) {
1149 if (or_null) return NULL;
1150
1151 ResourceMark rm;
1152 JavaThread *jt = (JavaThread *)THREAD;
1153 {
1154 // Atomic creation of array_klasses
1155 MutexLocker mc(Compile_lock, THREAD); // for vtables
1156 MutexLocker ma(MultiArray_lock, THREAD);
1157
1158 // Check if update has already taken place
1159 if (array_klasses() == NULL) {
1160 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1161 // use 'release' to pair with lock-free load
1162 release_set_array_klasses(k);
1163 }
1164 }
1165 }
1166 // _this will always be set at this point
1167 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1168 if (or_null) {
1169 return oak->array_klass_or_null(n);
1170 }
1171 return oak->array_klass(n, THREAD);
1172 }
1173
1174 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1175 return array_klass_impl(or_null, 1, THREAD);
1176 }
1177
1178 static int call_class_initializer_counter = 0; // for debugging
1179
1180 Method* InstanceKlass::class_initializer() const {
1181 Method* clinit = find_method(
1182 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1183 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1184 return clinit;
1185 }
1186 return NULL;
1187 }
1188
1189 void InstanceKlass::call_class_initializer(TRAPS) {
1190 if (ReplayCompiles &&
1191 (ReplaySuppressInitializers == 1 ||
1192 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1193 // Hide the existence of the initializer for the purpose of replaying the compile
1194 return;
1195 }
1196
1197 methodHandle h_method(THREAD, class_initializer());
1198 assert(!is_initialized(), "we cannot initialize twice");
1199 LogTarget(Info, class, init) lt;
1200 if (lt.is_enabled()) {
1201 ResourceMark rm;
1202 LogStream ls(lt);
1203 ls.print("%d Initializing ", call_class_initializer_counter++);
1204 name()->print_value_on(&ls);
1205 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1206 }
1207 if (h_method() != NULL) {
1208 JavaCallArguments args; // No arguments
1209 JavaValue result(T_VOID);
1210 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1211 }
1212 }
1213
1214
1215 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1216 InterpreterOopMap* entry_for) {
1217 // Lazily create the _oop_map_cache at first request
1218 // Lock-free access requires load_acquire.
1219 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1220 if (oop_map_cache == NULL) {
1221 MutexLockerEx x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1222 // Check if _oop_map_cache was allocated while we were waiting for this lock
1223 if ((oop_map_cache = _oop_map_cache) == NULL) {
1224 oop_map_cache = new OopMapCache();
1225 // Ensure _oop_map_cache is stable, since it is examined without a lock
1226 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1227 }
1228 }
1229 // _oop_map_cache is constant after init; lookup below does its own locking.
1230 oop_map_cache->lookup(method, bci, entry_for);
1231 }
1232
1233
1234 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1235 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1236 Symbol* f_name = fs.name();
1237 Symbol* f_sig = fs.signature();
1238 if (f_name == name && f_sig == sig) {
1239 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1240 return true;
1241 }
1242 }
1243 return false;
1244 }
1245
1246
1247 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1248 const int n = local_interfaces()->length();
1249 for (int i = 0; i < n; i++) {
1250 Klass* intf1 = local_interfaces()->at(i);
1251 assert(intf1->is_interface(), "just checking type");
1252 // search for field in current interface
1253 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1254 assert(fd->is_static(), "interface field must be static");
1255 return intf1;
1256 }
1257 // search for field in direct superinterfaces
1258 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1259 if (intf2 != NULL) return intf2;
1260 }
1261 // otherwise field lookup fails
1262 return NULL;
1263 }
1264
1265
1266 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1267 // search order according to newest JVM spec (5.4.3.2, p.167).
1268 // 1) search for field in current klass
1269 if (find_local_field(name, sig, fd)) {
1270 return const_cast<InstanceKlass*>(this);
1271 }
1272 // 2) search for field recursively in direct superinterfaces
1273 { Klass* intf = find_interface_field(name, sig, fd);
1274 if (intf != NULL) return intf;
1275 }
1276 // 3) apply field lookup recursively if superclass exists
1277 { Klass* supr = super();
1278 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1279 }
1280 // 4) otherwise field lookup fails
1281 return NULL;
1282 }
1283
1284
1285 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1286 // search order according to newest JVM spec (5.4.3.2, p.167).
1287 // 1) search for field in current klass
1288 if (find_local_field(name, sig, fd)) {
1289 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1290 }
1291 // 2) search for field recursively in direct superinterfaces
1292 if (is_static) {
1293 Klass* intf = find_interface_field(name, sig, fd);
1294 if (intf != NULL) return intf;
1295 }
1296 // 3) apply field lookup recursively if superclass exists
1297 { Klass* supr = super();
1298 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1299 }
1300 // 4) otherwise field lookup fails
1301 return NULL;
1302 }
1303
1304
1305 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1306 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1307 if (fs.offset() == offset) {
1308 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1309 if (fd->is_static() == is_static) return true;
1310 }
1311 }
1312 return false;
1313 }
1314
1315
1316 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1317 Klass* klass = const_cast<InstanceKlass*>(this);
1318 while (klass != NULL) {
1319 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1320 return true;
1321 }
1322 klass = klass->super();
1323 }
1324 return false;
1325 }
1326
1327
1328 void InstanceKlass::methods_do(void f(Method* method)) {
1329 // Methods aren't stable until they are loaded. This can be read outside
1330 // a lock through the ClassLoaderData for profiling
1331 if (!is_loaded()) {
1332 return;
1333 }
1334
1335 int len = methods()->length();
1336 for (int index = 0; index < len; index++) {
1337 Method* m = methods()->at(index);
1338 assert(m->is_method(), "must be method");
1339 f(m);
1340 }
1341 }
1342
1343
1344 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1345 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1346 if (fs.access_flags().is_static()) {
1347 fieldDescriptor& fd = fs.field_descriptor();
1348 cl->do_field(&fd);
1349 }
1350 }
1351 }
1352
1353
1354 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1355 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1356 if (fs.access_flags().is_static()) {
1357 fieldDescriptor& fd = fs.field_descriptor();
1358 f(&fd, mirror, CHECK);
1359 }
1360 }
1361 }
1362
1363
1364 static int compare_fields_by_offset(int* a, int* b) {
1365 return a[0] - b[0];
1366 }
1367
1368 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1369 InstanceKlass* super = superklass();
1370 if (super != NULL) {
1371 super->do_nonstatic_fields(cl);
1372 }
1373 fieldDescriptor fd;
1374 int length = java_fields_count();
1375 // In DebugInfo nonstatic fields are sorted by offset.
1376 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1377 int j = 0;
1378 for (int i = 0; i < length; i += 1) {
1379 fd.reinitialize(this, i);
1380 if (!fd.is_static()) {
1381 fields_sorted[j + 0] = fd.offset();
1382 fields_sorted[j + 1] = i;
1383 j += 2;
1384 }
1385 }
1386 if (j > 0) {
1387 length = j;
1388 // _sort_Fn is defined in growableArray.hpp.
1389 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1390 for (int i = 0; i < length; i += 2) {
1391 fd.reinitialize(this, fields_sorted[i + 1]);
1392 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1393 cl->do_field(&fd);
1394 }
1395 }
1396 FREE_C_HEAP_ARRAY(int, fields_sorted);
1397 }
1398
1399
1400 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1401 if (array_klasses() != NULL)
1402 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1403 }
1404
1405 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1406 if (array_klasses() != NULL)
1407 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1408 }
1409
1410 #ifdef ASSERT
1411 static int linear_search(const Array<Method*>* methods,
1412 const Symbol* name,
1413 const Symbol* signature) {
1414 const int len = methods->length();
1415 for (int index = 0; index < len; index++) {
1416 const Method* const m = methods->at(index);
1417 assert(m->is_method(), "must be method");
1418 if (m->signature() == signature && m->name() == name) {
1419 return index;
1420 }
1421 }
1422 return -1;
1423 }
1424 #endif
1425
1426 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1427 int len = methods->length();
1428 // methods are sorted, so do binary search
1429 int l = 0;
1430 int h = len - 1;
1431 while (l <= h) {
1432 int mid = (l + h) >> 1;
1433 Method* m = methods->at(mid);
1434 assert(m->is_method(), "must be method");
1435 int res = m->name()->fast_compare(name);
1436 if (res == 0) {
1437 return mid;
1438 } else if (res < 0) {
1439 l = mid + 1;
1440 } else {
1441 h = mid - 1;
1442 }
1443 }
1444 return -1;
1445 }
1446
1447 // find_method looks up the name/signature in the local methods array
1448 Method* InstanceKlass::find_method(const Symbol* name,
1449 const Symbol* signature) const {
1450 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1451 }
1452
1453 Method* InstanceKlass::find_method_impl(const Symbol* name,
1454 const Symbol* signature,
1455 OverpassLookupMode overpass_mode,
1456 StaticLookupMode static_mode,
1457 PrivateLookupMode private_mode) const {
1458 return InstanceKlass::find_method_impl(methods(),
1459 name,
1460 signature,
1461 overpass_mode,
1462 static_mode,
1463 private_mode);
1464 }
1465
1466 // find_instance_method looks up the name/signature in the local methods array
1467 // and skips over static methods
1468 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1469 const Symbol* name,
1470 const Symbol* signature) {
1471 Method* const meth = InstanceKlass::find_method_impl(methods,
1472 name,
1473 signature,
1474 find_overpass,
1475 skip_static,
1476 find_private);
1477 assert(((meth == NULL) || !meth->is_static()),
1478 "find_instance_method should have skipped statics");
1479 return meth;
1480 }
1481
1482 // find_instance_method looks up the name/signature in the local methods array
1483 // and skips over static methods
1484 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1485 return InstanceKlass::find_instance_method(methods(), name, signature);
1486 }
1487
1488 // Find looks up the name/signature in the local methods array
1489 // and filters on the overpass, static and private flags
1490 // This returns the first one found
1491 // note that the local methods array can have up to one overpass, one static
1492 // and one instance (private or not) with the same name/signature
1493 Method* InstanceKlass::find_local_method(const Symbol* name,
1494 const Symbol* signature,
1495 OverpassLookupMode overpass_mode,
1496 StaticLookupMode static_mode,
1497 PrivateLookupMode private_mode) const {
1498 return InstanceKlass::find_method_impl(methods(),
1499 name,
1500 signature,
1501 overpass_mode,
1502 static_mode,
1503 private_mode);
1504 }
1505
1506 // Find looks up the name/signature in the local methods array
1507 // and filters on the overpass, static and private flags
1508 // This returns the first one found
1509 // note that the local methods array can have up to one overpass, one static
1510 // and one instance (private or not) with the same name/signature
1511 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1512 const Symbol* name,
1513 const Symbol* signature,
1514 OverpassLookupMode overpass_mode,
1515 StaticLookupMode static_mode,
1516 PrivateLookupMode private_mode) {
1517 return InstanceKlass::find_method_impl(methods,
1518 name,
1519 signature,
1520 overpass_mode,
1521 static_mode,
1522 private_mode);
1523 }
1524
1525 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1526 const Symbol* name,
1527 const Symbol* signature) {
1528 return InstanceKlass::find_method_impl(methods,
1529 name,
1530 signature,
1531 find_overpass,
1532 find_static,
1533 find_private);
1534 }
1535
1536 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1537 const Symbol* name,
1538 const Symbol* signature,
1539 OverpassLookupMode overpass_mode,
1540 StaticLookupMode static_mode,
1541 PrivateLookupMode private_mode) {
1542 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1543 return hit >= 0 ? methods->at(hit): NULL;
1544 }
1545
1546 // true if method matches signature and conforms to skipping_X conditions.
1547 static bool method_matches(const Method* m,
1548 const Symbol* signature,
1549 bool skipping_overpass,
1550 bool skipping_static,
1551 bool skipping_private) {
1552 return ((m->signature() == signature) &&
1553 (!skipping_overpass || !m->is_overpass()) &&
1554 (!skipping_static || !m->is_static()) &&
1555 (!skipping_private || !m->is_private()));
1556 }
1557
1558 // Used directly for default_methods to find the index into the
1559 // default_vtable_indices, and indirectly by find_method
1560 // find_method_index looks in the local methods array to return the index
1561 // of the matching name/signature. If, overpass methods are being ignored,
1562 // the search continues to find a potential non-overpass match. This capability
1563 // is important during method resolution to prefer a static method, for example,
1564 // over an overpass method.
1565 // There is the possibility in any _method's array to have the same name/signature
1566 // for a static method, an overpass method and a local instance method
1567 // To correctly catch a given method, the search criteria may need
1568 // to explicitly skip the other two. For local instance methods, it
1569 // is often necessary to skip private methods
1570 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1571 const Symbol* name,
1572 const Symbol* signature,
1573 OverpassLookupMode overpass_mode,
1574 StaticLookupMode static_mode,
1575 PrivateLookupMode private_mode) {
1576 const bool skipping_overpass = (overpass_mode == skip_overpass);
1577 const bool skipping_static = (static_mode == skip_static);
1578 const bool skipping_private = (private_mode == skip_private);
1579 const int hit = binary_search(methods, name);
1580 if (hit != -1) {
1581 const Method* const m = methods->at(hit);
1582
1583 // Do linear search to find matching signature. First, quick check
1584 // for common case, ignoring overpasses if requested.
1585 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1586 return hit;
1587 }
1588
1589 // search downwards through overloaded methods
1590 int i;
1591 for (i = hit - 1; i >= 0; --i) {
1592 const Method* const m = methods->at(i);
1593 assert(m->is_method(), "must be method");
1594 if (m->name() != name) {
1595 break;
1596 }
1597 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1598 return i;
1599 }
1600 }
1601 // search upwards
1602 for (i = hit + 1; i < methods->length(); ++i) {
1603 const Method* const m = methods->at(i);
1604 assert(m->is_method(), "must be method");
1605 if (m->name() != name) {
1606 break;
1607 }
1608 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1609 return i;
1610 }
1611 }
1612 // not found
1613 #ifdef ASSERT
1614 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1615 linear_search(methods, name, signature);
1616 assert(-1 == index, "binary search should have found entry %d", index);
1617 #endif
1618 }
1619 return -1;
1620 }
1621
1622 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1623 return find_method_by_name(methods(), name, end);
1624 }
1625
1626 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1627 const Symbol* name,
1628 int* end_ptr) {
1629 assert(end_ptr != NULL, "just checking");
1630 int start = binary_search(methods, name);
1631 int end = start + 1;
1632 if (start != -1) {
1633 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1634 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1635 *end_ptr = end;
1636 return start;
1637 }
1638 return -1;
1639 }
1640
1641 // uncached_lookup_method searches both the local class methods array and all
1642 // superclasses methods arrays, skipping any overpass methods in superclasses.
1643 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1644 const Symbol* signature,
1645 OverpassLookupMode overpass_mode) const {
1646 OverpassLookupMode overpass_local_mode = overpass_mode;
1647 const Klass* klass = this;
1648 while (klass != NULL) {
1649 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1650 signature,
1651 overpass_local_mode,
1652 find_static,
1653 find_private);
1654 if (method != NULL) {
1655 return method;
1656 }
1657 klass = klass->super();
1658 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1659 }
1660 return NULL;
1661 }
1662
1663 #ifdef ASSERT
1664 // search through class hierarchy and return true if this class or
1665 // one of the superclasses was redefined
1666 bool InstanceKlass::has_redefined_this_or_super() const {
1667 const Klass* klass = this;
1668 while (klass != NULL) {
1669 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1670 return true;
1671 }
1672 klass = klass->super();
1673 }
1674 return false;
1675 }
1676 #endif
1677
1678 // lookup a method in the default methods list then in all transitive interfaces
1679 // Do NOT return private or static methods
1680 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1681 Symbol* signature) const {
1682 Method* m = NULL;
1683 if (default_methods() != NULL) {
1684 m = find_method(default_methods(), name, signature);
1685 }
1686 // Look up interfaces
1687 if (m == NULL) {
1688 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1689 }
1690 return m;
1691 }
1692
1693 // lookup a method in all the interfaces that this class implements
1694 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1695 // They should only be found in the initial InterfaceMethodRef
1696 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1697 Symbol* signature,
1698 DefaultsLookupMode defaults_mode) const {
1699 Array<Klass*>* all_ifs = transitive_interfaces();
1700 int num_ifs = all_ifs->length();
1701 InstanceKlass *ik = NULL;
1702 for (int i = 0; i < num_ifs; i++) {
1703 ik = InstanceKlass::cast(all_ifs->at(i));
1704 Method* m = ik->lookup_method(name, signature);
1705 if (m != NULL && m->is_public() && !m->is_static() &&
1706 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1707 return m;
1708 }
1709 }
1710 return NULL;
1711 }
1712
1713 /* jni_id_for_impl for jfieldIds only */
1714 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1715 MutexLocker ml(JfieldIdCreation_lock);
1716 // Retry lookup after we got the lock
1717 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1718 if (probe == NULL) {
1719 // Slow case, allocate new static field identifier
1720 probe = new JNIid(this, offset, jni_ids());
1721 set_jni_ids(probe);
1722 }
1723 return probe;
1724 }
1725
1726
1727 /* jni_id_for for jfieldIds only */
1728 JNIid* InstanceKlass::jni_id_for(int offset) {
1729 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1730 if (probe == NULL) {
1731 probe = jni_id_for_impl(offset);
1732 }
1733 return probe;
1734 }
1735
1736 u2 InstanceKlass::enclosing_method_data(int offset) const {
1737 const Array<jushort>* const inner_class_list = inner_classes();
1738 if (inner_class_list == NULL) {
1739 return 0;
1740 }
1741 const int length = inner_class_list->length();
1742 if (length % inner_class_next_offset == 0) {
1743 return 0;
1744 }
1745 const int index = length - enclosing_method_attribute_size;
1746 assert(offset < enclosing_method_attribute_size, "invalid offset");
1747 return inner_class_list->at(index + offset);
1748 }
1749
1750 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1751 u2 method_index) {
1752 Array<jushort>* inner_class_list = inner_classes();
1753 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1754 int length = inner_class_list->length();
1755 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1756 int index = length - enclosing_method_attribute_size;
1757 inner_class_list->at_put(
1758 index + enclosing_method_class_index_offset, class_index);
1759 inner_class_list->at_put(
1760 index + enclosing_method_method_index_offset, method_index);
1761 }
1762 }
1763
1764 // Lookup or create a jmethodID.
1765 // This code is called by the VMThread and JavaThreads so the
1766 // locking has to be done very carefully to avoid deadlocks
1767 // and/or other cache consistency problems.
1768 //
1769 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1770 size_t idnum = (size_t)method_h->method_idnum();
1771 jmethodID* jmeths = methods_jmethod_ids_acquire();
1772 size_t length = 0;
1773 jmethodID id = NULL;
1774
1775 // We use a double-check locking idiom here because this cache is
1776 // performance sensitive. In the normal system, this cache only
1777 // transitions from NULL to non-NULL which is safe because we use
1778 // release_set_methods_jmethod_ids() to advertise the new cache.
1779 // A partially constructed cache should never be seen by a racing
1780 // thread. We also use release_store() to save a new jmethodID
1781 // in the cache so a partially constructed jmethodID should never be
1782 // seen either. Cache reads of existing jmethodIDs proceed without a
1783 // lock, but cache writes of a new jmethodID requires uniqueness and
1784 // creation of the cache itself requires no leaks so a lock is
1785 // generally acquired in those two cases.
1786 //
1787 // If the RedefineClasses() API has been used, then this cache can
1788 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1789 // Cache creation requires no leaks and we require safety between all
1790 // cache accesses and freeing of the old cache so a lock is generally
1791 // acquired when the RedefineClasses() API has been used.
1792
1793 if (jmeths != NULL) {
1794 // the cache already exists
1795 if (!idnum_can_increment()) {
1796 // the cache can't grow so we can just get the current values
1797 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1798 } else {
1799 // cache can grow so we have to be more careful
1800 if (Threads::number_of_threads() == 0 ||
1801 SafepointSynchronize::is_at_safepoint()) {
1802 // we're single threaded or at a safepoint - no locking needed
1803 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1804 } else {
1805 MutexLocker ml(JmethodIdCreation_lock);
1806 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1807 }
1808 }
1809 }
1810 // implied else:
1811 // we need to allocate a cache so default length and id values are good
1812
1813 if (jmeths == NULL || // no cache yet
1814 length <= idnum || // cache is too short
1815 id == NULL) { // cache doesn't contain entry
1816
1817 // This function can be called by the VMThread so we have to do all
1818 // things that might block on a safepoint before grabbing the lock.
1819 // Otherwise, we can deadlock with the VMThread or have a cache
1820 // consistency issue. These vars keep track of what we might have
1821 // to free after the lock is dropped.
1822 jmethodID to_dealloc_id = NULL;
1823 jmethodID* to_dealloc_jmeths = NULL;
1824
1825 // may not allocate new_jmeths or use it if we allocate it
1826 jmethodID* new_jmeths = NULL;
1827 if (length <= idnum) {
1828 // allocate a new cache that might be used
1829 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1830 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1831 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1832 // cache size is stored in element[0], other elements offset by one
1833 new_jmeths[0] = (jmethodID)size;
1834 }
1835
1836 // allocate a new jmethodID that might be used
1837 jmethodID new_id = NULL;
1838 if (method_h->is_old() && !method_h->is_obsolete()) {
1839 // The method passed in is old (but not obsolete), we need to use the current version
1840 Method* current_method = method_with_idnum((int)idnum);
1841 assert(current_method != NULL, "old and but not obsolete, so should exist");
1842 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1843 } else {
1844 // It is the current version of the method or an obsolete method,
1845 // use the version passed in
1846 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1847 }
1848
1849 if (Threads::number_of_threads() == 0 ||
1850 SafepointSynchronize::is_at_safepoint()) {
1851 // we're single threaded or at a safepoint - no locking needed
1852 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1853 &to_dealloc_id, &to_dealloc_jmeths);
1854 } else {
1855 MutexLocker ml(JmethodIdCreation_lock);
1856 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1857 &to_dealloc_id, &to_dealloc_jmeths);
1858 }
1859
1860 // The lock has been dropped so we can free resources.
1861 // Free up either the old cache or the new cache if we allocated one.
1862 if (to_dealloc_jmeths != NULL) {
1863 FreeHeap(to_dealloc_jmeths);
1864 }
1865 // free up the new ID since it wasn't needed
1866 if (to_dealloc_id != NULL) {
1867 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1868 }
1869 }
1870 return id;
1871 }
1872
1873 // Figure out how many jmethodIDs haven't been allocated, and make
1874 // sure space for them is pre-allocated. This makes getting all
1875 // method ids much, much faster with classes with more than 8
1876 // methods, and has a *substantial* effect on performance with jvmti
1877 // code that loads all jmethodIDs for all classes.
1878 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1879 int new_jmeths = 0;
1880 int length = methods()->length();
1881 for (int index = start_offset; index < length; index++) {
1882 Method* m = methods()->at(index);
1883 jmethodID id = m->find_jmethod_id_or_null();
1884 if (id == NULL) {
1885 new_jmeths++;
1886 }
1887 }
1888 if (new_jmeths != 0) {
1889 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1890 }
1891 }
1892
1893 // Common code to fetch the jmethodID from the cache or update the
1894 // cache with the new jmethodID. This function should never do anything
1895 // that causes the caller to go to a safepoint or we can deadlock with
1896 // the VMThread or have cache consistency issues.
1897 //
1898 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1899 size_t idnum, jmethodID new_id,
1900 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1901 jmethodID** to_dealloc_jmeths_p) {
1902 assert(new_id != NULL, "sanity check");
1903 assert(to_dealloc_id_p != NULL, "sanity check");
1904 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1905 assert(Threads::number_of_threads() == 0 ||
1906 SafepointSynchronize::is_at_safepoint() ||
1907 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1908
1909 // reacquire the cache - we are locked, single threaded or at a safepoint
1910 jmethodID* jmeths = methods_jmethod_ids_acquire();
1911 jmethodID id = NULL;
1912 size_t length = 0;
1913
1914 if (jmeths == NULL || // no cache yet
1915 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1916 if (jmeths != NULL) {
1917 // copy any existing entries from the old cache
1918 for (size_t index = 0; index < length; index++) {
1919 new_jmeths[index+1] = jmeths[index+1];
1920 }
1921 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1922 }
1923 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1924 } else {
1925 // fetch jmethodID (if any) from the existing cache
1926 id = jmeths[idnum+1];
1927 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1928 }
1929 if (id == NULL) {
1930 // No matching jmethodID in the existing cache or we have a new
1931 // cache or we just grew the cache. This cache write is done here
1932 // by the first thread to win the foot race because a jmethodID
1933 // needs to be unique once it is generally available.
1934 id = new_id;
1935
1936 // The jmethodID cache can be read while unlocked so we have to
1937 // make sure the new jmethodID is complete before installing it
1938 // in the cache.
1939 OrderAccess::release_store(&jmeths[idnum+1], id);
1940 } else {
1941 *to_dealloc_id_p = new_id; // save new id for later delete
1942 }
1943 return id;
1944 }
1945
1946
1947 // Common code to get the jmethodID cache length and the jmethodID
1948 // value at index idnum if there is one.
1949 //
1950 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1951 size_t idnum, size_t *length_p, jmethodID* id_p) {
1952 assert(cache != NULL, "sanity check");
1953 assert(length_p != NULL, "sanity check");
1954 assert(id_p != NULL, "sanity check");
1955
1956 // cache size is stored in element[0], other elements offset by one
1957 *length_p = (size_t)cache[0];
1958 if (*length_p <= idnum) { // cache is too short
1959 *id_p = NULL;
1960 } else {
1961 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1962 }
1963 }
1964
1965
1966 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1967 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1968 size_t idnum = (size_t)method->method_idnum();
1969 jmethodID* jmeths = methods_jmethod_ids_acquire();
1970 size_t length; // length assigned as debugging crumb
1971 jmethodID id = NULL;
1972 if (jmeths != NULL && // If there is a cache
1973 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1974 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1975 }
1976 return id;
1977 }
1978
1979 inline DependencyContext InstanceKlass::dependencies() {
1980 DependencyContext dep_context(&_dep_context);
1981 return dep_context;
1982 }
1983
1984 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1985 return dependencies().mark_dependent_nmethods(changes);
1986 }
1987
1988 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1989 dependencies().add_dependent_nmethod(nm);
1990 }
1991
1992 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1993 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1994 }
1995
1996 #ifndef PRODUCT
1997 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1998 dependencies().print_dependent_nmethods(verbose);
1999 }
2000
2001 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2002 return dependencies().is_dependent_nmethod(nm);
2003 }
2004 #endif //PRODUCT
2005
2006 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2007 clean_implementors_list(is_alive);
2008 clean_method_data(is_alive);
2009
2010 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2011 DependencyContext dep_context(&_dep_context);
2012 dep_context.expunge_stale_entries();
2013 }
2014
2015 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2016 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2017 if (is_interface()) {
2018 if (ClassUnloading) {
2019 Klass* impl = implementor();
2020 if (impl != NULL) {
2021 if (!impl->is_loader_alive(is_alive)) {
2022 // remove this guy
2023 Klass** klass = adr_implementor();
2024 assert(klass != NULL, "null klass");
2025 if (klass != NULL) {
2026 *klass = NULL;
2027 }
2028 }
2029 }
2030 }
2031 }
2032 }
2033
2034 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2035 for (int m = 0; m < methods()->length(); m++) {
2036 MethodData* mdo = methods()->at(m)->method_data();
2037 if (mdo != NULL) {
2038 mdo->clean_method_data(is_alive);
2039 }
2040 }
2041 }
2042
2043 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2044 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2045 ResourceMark rm;
2046 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2047 return false;
2048 }
2049
2050 Array<Klass*>* local_interfaces = this->local_interfaces();
2051 if (local_interfaces != NULL) {
2052 int length = local_interfaces->length();
2053 for (int i = 0; i < length; i++) {
2054 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2055 if (!intf->has_passed_fingerprint_check()) {
2056 ResourceMark rm;
2057 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2058 return false;
2059 }
2060 }
2061 }
2062
2063 return true;
2064 }
2065
2066 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) {
2067 #if INCLUDE_AOT
2068 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2069 if (CalculateClassFingerprint) {
2070 // (1) We are running AOT to generate a shared library.
2071 return true;
2072 }
2073 if (DumpSharedSpaces) {
2074 // (2) We are running -Xshare:dump to create a shared archive
2075 return true;
2076 }
2077 if (UseAOT && is_anonymous) {
2078 // (3) We are using AOT code from a shared library and see an anonymous class
2079 return true;
2080 }
2081 #endif
2082
2083 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2084 // but do not store the 64-bit fingerprint to save space.
2085 return false;
2086 }
2087
2088 bool InstanceKlass::has_stored_fingerprint() const {
2089 #if INCLUDE_AOT
2090 return should_store_fingerprint() || is_shared();
2091 #else
2092 return false;
2093 #endif
2094 }
2095
2096 uint64_t InstanceKlass::get_stored_fingerprint() const {
2097 address adr = adr_fingerprint();
2098 if (adr != NULL) {
2099 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2100 }
2101 return 0;
2102 }
2103
2104 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2105 address adr = adr_fingerprint();
2106 if (adr != NULL) {
2107 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2108
2109 ResourceMark rm;
2110 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2111 }
2112 }
2113
2114 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2115 Klass::metaspace_pointers_do(it);
2116
2117 if (log_is_enabled(Trace, cds)) {
2118 ResourceMark rm;
2119 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2120 }
2121
2122 it->push(&_annotations);
2123 it->push((Klass**)&_array_klasses);
2124 it->push(&_constants);
2125 it->push(&_inner_classes);
2126 it->push(&_array_name);
2127 #if INCLUDE_JVMTI
2128 it->push(&_previous_versions);
2129 #endif
2130 it->push(&_methods);
2131 it->push(&_default_methods);
2132 it->push(&_local_interfaces);
2133 it->push(&_transitive_interfaces);
2134 it->push(&_method_ordering);
2135 it->push(&_default_vtable_indices);
2136 it->push(&_fields);
2137
2138 if (itable_length() > 0) {
2139 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2140 int method_table_offset_in_words = ioe->offset()/wordSize;
2141 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2142 / itableOffsetEntry::size();
2143
2144 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2145 if (ioe->interface_klass() != NULL) {
2146 it->push(ioe->interface_klass_addr());
2147 itableMethodEntry* ime = ioe->first_method_entry(this);
2148 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2149 for (int index = 0; index < n; index ++) {
2150 it->push(ime[index].method_addr());
2151 }
2152 }
2153 }
2154 }
2155 }
2156
2157 void InstanceKlass::remove_unshareable_info() {
2158 Klass::remove_unshareable_info();
2159
2160 if (is_in_error_state()) {
2161 // Classes are attempted to link during dumping and may fail,
2162 // but these classes are still in the dictionary and class list in CLD.
2163 // Check in_error state first because in_error is > linked state, so
2164 // is_linked() is true.
2165 // If there's a linking error, there is nothing else to remove.
2166 return;
2167 }
2168
2169 // Unlink the class
2170 if (is_linked()) {
2171 unlink_class();
2172 }
2173 init_implementor();
2174
2175 constants()->remove_unshareable_info();
2176
2177 for (int i = 0; i < methods()->length(); i++) {
2178 Method* m = methods()->at(i);
2179 m->remove_unshareable_info();
2180 }
2181
2182 // do array classes also.
2183 if (array_klasses() != NULL) {
2184 array_klasses()->remove_unshareable_info();
2185 }
2186
2187 // These are not allocated from metaspace, but they should should all be empty
2188 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2189 guarantee(_source_debug_extension == NULL, "must be");
2190 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2191 guarantee(_osr_nmethods_head == NULL, "must be");
2192
2193 #if INCLUDE_JVMTI
2194 guarantee(_breakpoints == NULL, "must be");
2195 guarantee(_previous_versions == NULL, "must be");
2196 #endif
2197
2198 _init_thread = NULL;
2199 _methods_jmethod_ids = NULL;
2200 _jni_ids = NULL;
2201 _oop_map_cache = NULL;
2202 }
2203
2204 void InstanceKlass::remove_java_mirror() {
2205 Klass::remove_java_mirror();
2206
2207 // do array classes also.
2208 if (array_klasses() != NULL) {
2209 array_klasses()->remove_java_mirror();
2210 }
2211 }
2212
2213 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2214 set_package(loader_data, CHECK);
2215 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2216
2217 Array<Method*>* methods = this->methods();
2218 int num_methods = methods->length();
2219 for (int index2 = 0; index2 < num_methods; ++index2) {
2220 methodHandle m(THREAD, methods->at(index2));
2221 m->restore_unshareable_info(CHECK);
2222 }
2223 if (JvmtiExport::has_redefined_a_class()) {
2224 // Reinitialize vtable because RedefineClasses may have changed some
2225 // entries in this vtable for super classes so the CDS vtable might
2226 // point to old or obsolete entries. RedefineClasses doesn't fix up
2227 // vtables in the shared system dictionary, only the main one.
2228 // It also redefines the itable too so fix that too.
2229 ResourceMark rm(THREAD);
2230 vtable().initialize_vtable(false, CHECK);
2231 itable().initialize_itable(false, CHECK);
2232 }
2233
2234 // restore constant pool resolved references
2235 constants()->restore_unshareable_info(CHECK);
2236
2237 if (array_klasses() != NULL) {
2238 // Array classes have null protection domain.
2239 // --> see ArrayKlass::complete_create_array_klass()
2240 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2241 }
2242 }
2243
2244 // returns true IFF is_in_error_state() has been changed as a result of this call.
2245 bool InstanceKlass::check_sharing_error_state() {
2246 assert(DumpSharedSpaces, "should only be called during dumping");
2247 bool old_state = is_in_error_state();
2248
2249 if (!is_in_error_state()) {
2250 bool bad = false;
2251 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2252 if (sup->is_in_error_state()) {
2253 bad = true;
2254 break;
2255 }
2256 }
2257 if (!bad) {
2258 Array<Klass*>* interfaces = transitive_interfaces();
2259 for (int i = 0; i < interfaces->length(); i++) {
2260 Klass* iface = interfaces->at(i);
2261 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2262 bad = true;
2263 break;
2264 }
2265 }
2266 }
2267
2268 if (bad) {
2269 set_in_error_state();
2270 }
2271 }
2272
2273 return (old_state != is_in_error_state());
2274 }
2275
2276 #if INCLUDE_JVMTI
2277 static void clear_all_breakpoints(Method* m) {
2278 m->clear_all_breakpoints();
2279 }
2280 #endif
2281
2282 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2283 // notify the debugger
2284 if (JvmtiExport::should_post_class_unload()) {
2285 JvmtiExport::post_class_unload(ik);
2286 }
2287
2288 // notify ClassLoadingService of class unload
2289 ClassLoadingService::notify_class_unloaded(ik);
2290 }
2291
2292 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2293 // Clean up C heap
2294 ik->release_C_heap_structures();
2295 ik->constants()->release_C_heap_structures();
2296 }
2297
2298 void InstanceKlass::release_C_heap_structures() {
2299 // Can't release the constant pool here because the constant pool can be
2300 // deallocated separately from the InstanceKlass for default methods and
2301 // redefine classes.
2302
2303 // Deallocate oop map cache
2304 if (_oop_map_cache != NULL) {
2305 delete _oop_map_cache;
2306 _oop_map_cache = NULL;
2307 }
2308
2309 // Deallocate JNI identifiers for jfieldIDs
2310 JNIid::deallocate(jni_ids());
2311 set_jni_ids(NULL);
2312
2313 jmethodID* jmeths = methods_jmethod_ids_acquire();
2314 if (jmeths != (jmethodID*)NULL) {
2315 release_set_methods_jmethod_ids(NULL);
2316 FreeHeap(jmeths);
2317 }
2318
2319 // Release dependencies.
2320 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2321 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2322 // context can contain live dependencies, since there's a race between nmethod &
2323 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2324 // dependencies aren't removed from the context associated with the class (see
2325 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2326 // live dependencies pointing to unloaded nmethods and causes a crash in
2327 // DC::remove_all_dependents() when it touches unloaded nmethod.
2328 dependencies().wipe();
2329
2330 #if INCLUDE_JVMTI
2331 // Deallocate breakpoint records
2332 if (breakpoints() != 0x0) {
2333 methods_do(clear_all_breakpoints);
2334 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2335 }
2336
2337 // deallocate the cached class file
2338 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2339 os::free(_cached_class_file);
2340 _cached_class_file = NULL;
2341 }
2342 #endif
2343
2344 // Decrement symbol reference counts associated with the unloaded class.
2345 if (_name != NULL) _name->decrement_refcount();
2346 // unreference array name derived from this class name (arrays of an unloaded
2347 // class can't be referenced anymore).
2348 if (_array_name != NULL) _array_name->decrement_refcount();
2349 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2350
2351 assert(_total_instanceKlass_count >= 1, "Sanity check");
2352 Atomic::dec(&_total_instanceKlass_count);
2353 }
2354
2355 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2356 if (array == NULL) {
2357 _source_debug_extension = NULL;
2358 } else {
2359 // Adding one to the attribute length in order to store a null terminator
2360 // character could cause an overflow because the attribute length is
2361 // already coded with an u4 in the classfile, but in practice, it's
2362 // unlikely to happen.
2363 assert((length+1) > length, "Overflow checking");
2364 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2365 for (int i = 0; i < length; i++) {
2366 sde[i] = array[i];
2367 }
2368 sde[length] = '\0';
2369 _source_debug_extension = sde;
2370 }
2371 }
2372
2373 address InstanceKlass::static_field_addr(int offset) {
2374 assert(offset >= InstanceMirrorKlass::offset_of_static_fields(), "has already been adjusted");
2375 return (address)(offset + cast_from_oop<intptr_t>(java_mirror()));
2376 }
2377
2378
2379 const char* InstanceKlass::signature_name() const {
2380 int hash_len = 0;
2381 char hash_buf[40];
2382
2383 // If this is an anonymous class, append a hash to make the name unique
2384 if (is_anonymous()) {
2385 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2386 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2387 hash_len = (int)strlen(hash_buf);
2388 }
2389
2390 // Get the internal name as a c string
2391 const char* src = (const char*) (name()->as_C_string());
2392 const int src_length = (int)strlen(src);
2393
2394 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2395
2396 // Add L as type indicator
2397 int dest_index = 0;
2398 dest[dest_index++] = 'L';
2399
2400 // Add the actual class name
2401 for (int src_index = 0; src_index < src_length; ) {
2402 dest[dest_index++] = src[src_index++];
2403 }
2404
2405 // If we have a hash, append it
2406 for (int hash_index = 0; hash_index < hash_len; ) {
2407 dest[dest_index++] = hash_buf[hash_index++];
2408 }
2409
2410 // Add the semicolon and the NULL
2411 dest[dest_index++] = ';';
2412 dest[dest_index] = '\0';
2413 return dest;
2414 }
2415
2416 // Used to obtain the package name from a fully qualified class name.
2417 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2418 if (name == NULL) {
2419 return NULL;
2420 } else {
2421 if (name->utf8_length() <= 0) {
2422 return NULL;
2423 }
2424 ResourceMark rm;
2425 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2426 if (package_name == NULL) {
2427 return NULL;
2428 }
2429 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2430 return pkg_name;
2431 }
2432 }
2433
2434 ModuleEntry* InstanceKlass::module() const {
2435 if (!in_unnamed_package()) {
2436 return _package_entry->module();
2437 }
2438 const Klass* host = host_klass();
2439 if (host == NULL) {
2440 return class_loader_data()->unnamed_module();
2441 }
2442 return host->class_loader_data()->unnamed_module();
2443 }
2444
2445 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2446
2447 // ensure java/ packages only loaded by boot or platform builtin loaders
2448 Handle class_loader(THREAD, loader_data->class_loader());
2449 check_prohibited_package(name(), class_loader, CHECK);
2450
2451 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2452
2453 if (pkg_name != NULL && loader_data != NULL) {
2454
2455 // Find in class loader's package entry table.
2456 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2457
2458 // If the package name is not found in the loader's package
2459 // entry table, it is an indication that the package has not
2460 // been defined. Consider it defined within the unnamed module.
2461 if (_package_entry == NULL) {
2462 ResourceMark rm;
2463
2464 if (!ModuleEntryTable::javabase_defined()) {
2465 // Before java.base is defined during bootstrapping, define all packages in
2466 // the java.base module. If a non-java.base package is erroneously placed
2467 // in the java.base module it will be caught later when java.base
2468 // is defined by ModuleEntryTable::verify_javabase_packages check.
2469 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2470 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2471 } else {
2472 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2473 _package_entry = loader_data->packages()->lookup(pkg_name,
2474 loader_data->unnamed_module());
2475 }
2476
2477 // A package should have been successfully created
2478 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2479 name()->as_C_string(), loader_data->loader_name());
2480 }
2481
2482 if (log_is_enabled(Debug, module)) {
2483 ResourceMark rm;
2484 ModuleEntry* m = _package_entry->module();
2485 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2486 external_name(),
2487 pkg_name->as_C_string(),
2488 loader_data->loader_name(),
2489 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2490 }
2491 } else {
2492 ResourceMark rm;
2493 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2494 external_name(),
2495 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2496 UNNAMED_MODULE);
2497 }
2498 }
2499
2500
2501 // different versions of is_same_class_package
2502
2503 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2504 oop classloader1 = this->class_loader();
2505 PackageEntry* classpkg1 = this->package();
2506 if (class2->is_objArray_klass()) {
2507 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2508 }
2509
2510 oop classloader2;
2511 PackageEntry* classpkg2;
2512 if (class2->is_instance_klass()) {
2513 classloader2 = class2->class_loader();
2514 classpkg2 = class2->package();
2515 } else {
2516 assert(class2->is_typeArray_klass(), "should be type array");
2517 classloader2 = NULL;
2518 classpkg2 = NULL;
2519 }
2520
2521 // Same package is determined by comparing class loader
2522 // and package entries. Both must be the same. This rule
2523 // applies even to classes that are defined in the unnamed
2524 // package, they still must have the same class loader.
2525 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2526 return true;
2527 }
2528
2529 return false;
2530 }
2531
2532 // return true if this class and other_class are in the same package. Classloader
2533 // and classname information is enough to determine a class's package
2534 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2535 const Symbol* other_class_name) const {
2536 if (class_loader() != other_class_loader) {
2537 return false;
2538 }
2539 if (name()->fast_compare(other_class_name) == 0) {
2540 return true;
2541 }
2542
2543 {
2544 ResourceMark rm;
2545
2546 bool bad_class_name = false;
2547 const char* other_pkg =
2548 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2549 if (bad_class_name) {
2550 return false;
2551 }
2552 // Check that package_from_name() returns NULL, not "", if there is no package.
2553 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2554
2555 const Symbol* const this_package_name =
2556 this->package() != NULL ? this->package()->name() : NULL;
2557
2558 if (this_package_name == NULL || other_pkg == NULL) {
2559 // One of the two doesn't have a package. Only return true if the other
2560 // one also doesn't have a package.
2561 return (const char*)this_package_name == other_pkg;
2562 }
2563
2564 // Check if package is identical
2565 return this_package_name->equals(other_pkg);
2566 }
2567 }
2568
2569 // Returns true iff super_method can be overridden by a method in targetclassname
2570 // See JLS 3rd edition 8.4.6.1
2571 // Assumes name-signature match
2572 // "this" is InstanceKlass of super_method which must exist
2573 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2574 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2575 // Private methods can not be overridden
2576 if (super_method->is_private()) {
2577 return false;
2578 }
2579 // If super method is accessible, then override
2580 if ((super_method->is_protected()) ||
2581 (super_method->is_public())) {
2582 return true;
2583 }
2584 // Package-private methods are not inherited outside of package
2585 assert(super_method->is_package_private(), "must be package private");
2586 return(is_same_class_package(targetclassloader(), targetclassname));
2587 }
2588
2589 // Only boot and platform class loaders can define classes in "java/" packages.
2590 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2591 Handle class_loader,
2592 TRAPS) {
2593 if (!class_loader.is_null() &&
2594 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2595 class_name != NULL) {
2596 ResourceMark rm(THREAD);
2597 char* name = class_name->as_C_string();
2598 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2599 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2600 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2601 name = pkg_name->as_C_string();
2602 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2603 StringUtils::replace_no_expand(name, "/", ".");
2604 const char* msg_text1 = "Class loader (instance of): ";
2605 const char* msg_text2 = " tried to load prohibited package name: ";
2606 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2607 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2608 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2609 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2610 }
2611 }
2612 return;
2613 }
2614
2615 // tell if two classes have the same enclosing class (at package level)
2616 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2617 if (class2 == this) return true;
2618 if (!class2->is_instance_klass()) return false;
2619
2620 // must be in same package before we try anything else
2621 if (!is_same_class_package(class2))
2622 return false;
2623
2624 // As long as there is an outer_this.getEnclosingClass,
2625 // shift the search outward.
2626 const InstanceKlass* outer_this = this;
2627 for (;;) {
2628 // As we walk along, look for equalities between outer_this and class2.
2629 // Eventually, the walks will terminate as outer_this stops
2630 // at the top-level class around the original class.
2631 bool ignore_inner_is_member;
2632 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2633 CHECK_false);
2634 if (next == NULL) break;
2635 if (next == class2) return true;
2636 outer_this = InstanceKlass::cast(next);
2637 }
2638
2639 // Now do the same for class2.
2640 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2641 for (;;) {
2642 bool ignore_inner_is_member;
2643 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2644 CHECK_false);
2645 if (next == NULL) break;
2646 // Might as well check the new outer against all available values.
2647 if (next == this) return true;
2648 if (next == outer_this) return true;
2649 outer2 = InstanceKlass::cast(next);
2650 }
2651
2652 // If by this point we have not found an equality between the
2653 // two classes, we know they are in separate package members.
2654 return false;
2655 }
2656
2657 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2658 constantPoolHandle i_cp(THREAD, constants());
2659 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2660 int ioff = iter.inner_class_info_index();
2661 if (ioff != 0) {
2662 // Check to see if the name matches the class we're looking for
2663 // before attempting to find the class.
2664 if (i_cp->klass_name_at_matches(this, ioff)) {
2665 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2666 if (this == inner_klass) {
2667 *ooff = iter.outer_class_info_index();
2668 *noff = iter.inner_name_index();
2669 return true;
2670 }
2671 }
2672 }
2673 }
2674 return false;
2675 }
2676
2677 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2678 InstanceKlass* outer_klass = NULL;
2679 *inner_is_member = false;
2680 int ooff = 0, noff = 0;
2681 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2682 if (has_inner_classes_attr) {
2683 constantPoolHandle i_cp(THREAD, constants());
2684 if (ooff != 0) {
2685 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2686 outer_klass = InstanceKlass::cast(ok);
2687 *inner_is_member = true;
2688 }
2689 if (NULL == outer_klass) {
2690 // It may be anonymous; try for that.
2691 int encl_method_class_idx = enclosing_method_class_index();
2692 if (encl_method_class_idx != 0) {
2693 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2694 outer_klass = InstanceKlass::cast(ok);
2695 *inner_is_member = false;
2696 }
2697 }
2698 }
2699
2700 // If no inner class attribute found for this class.
2701 if (NULL == outer_klass) return NULL;
2702
2703 // Throws an exception if outer klass has not declared k as an inner klass
2704 // We need evidence that each klass knows about the other, or else
2705 // the system could allow a spoof of an inner class to gain access rights.
2706 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2707 return outer_klass;
2708 }
2709
2710 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2711 jint access = access_flags().as_int();
2712
2713 // But check if it happens to be member class.
2714 InnerClassesIterator iter(this);
2715 for (; !iter.done(); iter.next()) {
2716 int ioff = iter.inner_class_info_index();
2717 // Inner class attribute can be zero, skip it.
2718 // Strange but true: JVM spec. allows null inner class refs.
2719 if (ioff == 0) continue;
2720
2721 // only look at classes that are already loaded
2722 // since we are looking for the flags for our self.
2723 Symbol* inner_name = constants()->klass_name_at(ioff);
2724 if (name() == inner_name) {
2725 // This is really a member class.
2726 access = iter.inner_access_flags();
2727 break;
2728 }
2729 }
2730 // Remember to strip ACC_SUPER bit
2731 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2732 }
2733
2734 jint InstanceKlass::jvmti_class_status() const {
2735 jint result = 0;
2736
2737 if (is_linked()) {
2738 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2739 }
2740
2741 if (is_initialized()) {
2742 assert(is_linked(), "Class status is not consistent");
2743 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2744 }
2745 if (is_in_error_state()) {
2746 result |= JVMTI_CLASS_STATUS_ERROR;
2747 }
2748 return result;
2749 }
2750
2751 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2752 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2753 int method_table_offset_in_words = ioe->offset()/wordSize;
2754 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2755 / itableOffsetEntry::size();
2756
2757 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2758 // If the interface isn't implemented by the receiver class,
2759 // the VM should throw IncompatibleClassChangeError.
2760 if (cnt >= nof_interfaces) {
2761 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2762 }
2763
2764 Klass* ik = ioe->interface_klass();
2765 if (ik == holder) break;
2766 }
2767
2768 itableMethodEntry* ime = ioe->first_method_entry(this);
2769 Method* m = ime[index].method();
2770 if (m == NULL) {
2771 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2772 }
2773 return m;
2774 }
2775
2776
2777 #if INCLUDE_JVMTI
2778 // update default_methods for redefineclasses for methods that are
2779 // not yet in the vtable due to concurrent subclass define and superinterface
2780 // redefinition
2781 // Note: those in the vtable, should have been updated via adjust_method_entries
2782 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2783 // search the default_methods for uses of either obsolete or EMCP methods
2784 if (default_methods() != NULL) {
2785 for (int index = 0; index < default_methods()->length(); index ++) {
2786 Method* old_method = default_methods()->at(index);
2787 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2788 continue; // skip uninteresting entries
2789 }
2790 assert(!old_method->is_deleted(), "default methods may not be deleted");
2791
2792 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2793
2794 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2795 assert(old_method != new_method, "sanity check");
2796
2797 default_methods()->at_put(index, new_method);
2798 if (log_is_enabled(Info, redefine, class, update)) {
2799 ResourceMark rm;
2800 if (!(*trace_name_printed)) {
2801 log_info(redefine, class, update)
2802 ("adjust: klassname=%s default methods from name=%s",
2803 external_name(), old_method->method_holder()->external_name());
2804 *trace_name_printed = true;
2805 }
2806 log_debug(redefine, class, update, vtables)
2807 ("default method update: %s(%s) ",
2808 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2809 }
2810 }
2811 }
2812 }
2813 #endif // INCLUDE_JVMTI
2814
2815 // On-stack replacement stuff
2816 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2817 // only one compilation can be active
2818 {
2819 // This is a short non-blocking critical region, so the no safepoint check is ok.
2820 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2821 assert(n->is_osr_method(), "wrong kind of nmethod");
2822 n->set_osr_link(osr_nmethods_head());
2823 set_osr_nmethods_head(n);
2824 // Raise the highest osr level if necessary
2825 if (TieredCompilation) {
2826 Method* m = n->method();
2827 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2828 }
2829 }
2830
2831 // Get rid of the osr methods for the same bci that have lower levels.
2832 if (TieredCompilation) {
2833 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2834 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2835 if (inv != NULL && inv->is_in_use()) {
2836 inv->make_not_entrant();
2837 }
2838 }
2839 }
2840 }
2841
2842 // Remove osr nmethod from the list. Return true if found and removed.
2843 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2844 // This is a short non-blocking critical region, so the no safepoint check is ok.
2845 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2846 assert(n->is_osr_method(), "wrong kind of nmethod");
2847 nmethod* last = NULL;
2848 nmethod* cur = osr_nmethods_head();
2849 int max_level = CompLevel_none; // Find the max comp level excluding n
2850 Method* m = n->method();
2851 // Search for match
2852 bool found = false;
2853 while(cur != NULL && cur != n) {
2854 if (TieredCompilation && m == cur->method()) {
2855 // Find max level before n
2856 max_level = MAX2(max_level, cur->comp_level());
2857 }
2858 last = cur;
2859 cur = cur->osr_link();
2860 }
2861 nmethod* next = NULL;
2862 if (cur == n) {
2863 found = true;
2864 next = cur->osr_link();
2865 if (last == NULL) {
2866 // Remove first element
2867 set_osr_nmethods_head(next);
2868 } else {
2869 last->set_osr_link(next);
2870 }
2871 }
2872 n->set_osr_link(NULL);
2873 if (TieredCompilation) {
2874 cur = next;
2875 while (cur != NULL) {
2876 // Find max level after n
2877 if (m == cur->method()) {
2878 max_level = MAX2(max_level, cur->comp_level());
2879 }
2880 cur = cur->osr_link();
2881 }
2882 m->set_highest_osr_comp_level(max_level);
2883 }
2884 return found;
2885 }
2886
2887 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2888 // This is a short non-blocking critical region, so the no safepoint check is ok.
2889 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2890 nmethod* osr = osr_nmethods_head();
2891 int found = 0;
2892 while (osr != NULL) {
2893 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2894 if (osr->method() == m) {
2895 osr->mark_for_deoptimization();
2896 found++;
2897 }
2898 osr = osr->osr_link();
2899 }
2900 return found;
2901 }
2902
2903 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2904 // This is a short non-blocking critical region, so the no safepoint check is ok.
2905 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2906 nmethod* osr = osr_nmethods_head();
2907 nmethod* best = NULL;
2908 while (osr != NULL) {
2909 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2910 // There can be a time when a c1 osr method exists but we are waiting
2911 // for a c2 version. When c2 completes its osr nmethod we will trash
2912 // the c1 version and only be able to find the c2 version. However
2913 // while we overflow in the c1 code at back branches we don't want to
2914 // try and switch to the same code as we are already running
2915
2916 if (osr->method() == m &&
2917 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2918 if (match_level) {
2919 if (osr->comp_level() == comp_level) {
2920 // Found a match - return it.
2921 return osr;
2922 }
2923 } else {
2924 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2925 if (osr->comp_level() == CompLevel_highest_tier) {
2926 // Found the best possible - return it.
2927 return osr;
2928 }
2929 best = osr;
2930 }
2931 }
2932 }
2933 osr = osr->osr_link();
2934 }
2935 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2936 return best;
2937 }
2938 return NULL;
2939 }
2940
2941 // -----------------------------------------------------------------------------------------------------
2942 // Printing
2943
2944 #ifndef PRODUCT
2945
2946 #define BULLET " - "
2947
2948 static const char* state_names[] = {
2949 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2950 };
2951
2952 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
2953 ResourceMark rm;
2954 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
2955 for (int i = 0; i < len; i++) forward_refs[i] = 0;
2956 for (int i = 0; i < len; i++) {
2957 intptr_t e = start[i];
2958 st->print("%d : " INTPTR_FORMAT, i, e);
2959 if (forward_refs[i] != 0) {
2960 int from = forward_refs[i];
2961 int off = (int) start[from];
2962 st->print(" (offset %d <= [%d])", off, from);
2963 }
2964 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2965 st->print(" ");
2966 ((Metadata*)e)->print_value_on(st);
2967 } else if (self != NULL && e > 0 && e < 0x10000) {
2968 address location = self + e;
2969 int index = (int)((intptr_t*)location - start);
2970 st->print(" (offset %d => [%d])", (int)e, index);
2971 if (index >= 0 && index < len)
2972 forward_refs[index] = i;
2973 }
2974 st->cr();
2975 }
2976 }
2977
2978 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2979 return print_vtable(NULL, reinterpret_cast<intptr_t*>(start), len, st);
2980 }
2981
2982 template<typename T>
2983 static void print_array_on(outputStream* st, Array<T>* array) {
2984 if (array == NULL) { st->print_cr("NULL"); return; }
2985 array->print_value_on(st); st->cr();
2986 if (Verbose || WizardMode) {
2987 for (int i = 0; i < array->length(); i++) {
2988 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
2989 }
2990 }
2991 }
2992
2993 static void print_array_on(outputStream* st, Array<int>* array) {
2994 if (array == NULL) { st->print_cr("NULL"); return; }
2995 array->print_value_on(st); st->cr();
2996 if (Verbose || WizardMode) {
2997 for (int i = 0; i < array->length(); i++) {
2998 st->print("%d : %d", i, array->at(i)); st->cr();
2999 }
3000 }
3001 }
3002
3003 void InstanceKlass::print_on(outputStream* st) const {
3004 assert(is_klass(), "must be klass");
3005 Klass::print_on(st);
3006
3007 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3008 st->print(BULLET"klass size: %d", size()); st->cr();
3009 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3010 st->print(BULLET"misc flags: 0x%x", _misc_flags); st->cr();
3011 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3012 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3013 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3014 st->print(BULLET"sub: ");
3015 Klass* sub = subklass();
3016 int n;
3017 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3018 if (n < MaxSubklassPrintSize) {
3019 sub->print_value_on(st);
3020 st->print(" ");
3021 }
3022 }
3023 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3024 st->cr();
3025
3026 if (is_interface()) {
3027 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3028 if (nof_implementors() == 1) {
3029 st->print_cr(BULLET"implementor: ");
3030 st->print(" ");
3031 implementor()->print_value_on(st);
3032 st->cr();
3033 }
3034 }
3035
3036 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3037 st->print(BULLET"methods: "); print_array_on(st, methods());
3038 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3039 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3040 if (default_vtable_indices() != NULL) {
3041 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3042 }
3043 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3044 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3045 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3046 if (class_loader_data() != NULL) {
3047 st->print(BULLET"class loader data: ");
3048 class_loader_data()->print_value_on(st);
3049 st->cr();
3050 }
3051 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3052 if (source_file_name() != NULL) {
3053 st->print(BULLET"source file: ");
3054 source_file_name()->print_value_on(st);
3055 st->cr();
3056 }
3057 if (source_debug_extension() != NULL) {
3058 st->print(BULLET"source debug extension: ");
3059 st->print("%s", source_debug_extension());
3060 st->cr();
3061 }
3062 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3063 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3064 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3065 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3066 {
3067 bool have_pv = false;
3068 // previous versions are linked together through the InstanceKlass
3069 for (InstanceKlass* pv_node = previous_versions();
3070 pv_node != NULL;
3071 pv_node = pv_node->previous_versions()) {
3072 if (!have_pv)
3073 st->print(BULLET"previous version: ");
3074 have_pv = true;
3075 pv_node->constants()->print_value_on(st);
3076 }
3077 if (have_pv) st->cr();
3078 }
3079
3080 if (generic_signature() != NULL) {
3081 st->print(BULLET"generic signature: ");
3082 generic_signature()->print_value_on(st);
3083 st->cr();
3084 }
3085 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3086 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3087 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3088 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3089 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3090 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(NULL, start_of_itable(), itable_length(), st);
3091 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3092 FieldPrinter print_static_field(st);
3093 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3094 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3095 FieldPrinter print_nonstatic_field(st);
3096 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3097 ik->do_nonstatic_fields(&print_nonstatic_field);
3098
3099 st->print(BULLET"non-static oop maps: ");
3100 OopMapBlock* map = start_of_nonstatic_oop_maps();
3101 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3102 while (map < end_map) {
3103 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3104 map++;
3105 }
3106 st->cr();
3107 }
3108
3109 #endif //PRODUCT
3110
3111 void InstanceKlass::print_value_on(outputStream* st) const {
3112 assert(is_klass(), "must be klass");
3113 if (Verbose || WizardMode) access_flags().print_on(st);
3114 name()->print_value_on(st);
3115 }
3116
3117 #ifndef PRODUCT
3118
3119 void FieldPrinter::do_field(fieldDescriptor* fd) {
3120 _st->print(BULLET);
3121 if (_obj == NULL) {
3122 fd->print_on(_st);
3123 _st->cr();
3124 } else {
3125 fd->print_on_for(_st, _obj);
3126 _st->cr();
3127 }
3128 }
3129
3130
3131 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3132 Klass::oop_print_on(obj, st);
3133
3134 if (this == SystemDictionary::String_klass()) {
3135 typeArrayOop value = java_lang_String::value(obj);
3136 juint length = java_lang_String::length(obj);
3137 if (value != NULL &&
3138 value->is_typeArray() &&
3139 length <= (juint) value->length()) {
3140 st->print(BULLET"string: ");
3141 java_lang_String::print(obj, st);
3142 st->cr();
3143 if (!WizardMode) return; // that is enough
3144 }
3145 }
3146
3147 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3148 FieldPrinter print_field(st, obj);
3149 do_nonstatic_fields(&print_field);
3150
3151 if (this == SystemDictionary::Class_klass()) {
3152 st->print(BULLET"signature: ");
3153 java_lang_Class::print_signature(obj, st);
3154 st->cr();
3155 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3156 st->print(BULLET"fake entry for mirror: ");
3157 mirrored_klass->print_value_on_maybe_null(st);
3158 st->cr();
3159 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3160 st->print(BULLET"fake entry for array: ");
3161 array_klass->print_value_on_maybe_null(st);
3162 st->cr();
3163 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3164 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3165 Klass* real_klass = java_lang_Class::as_Klass(obj);
3166 if (real_klass != NULL && real_klass->is_instance_klass()) {
3167 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3168 }
3169 } else if (this == SystemDictionary::MethodType_klass()) {
3170 st->print(BULLET"signature: ");
3171 java_lang_invoke_MethodType::print_signature(obj, st);
3172 st->cr();
3173 }
3174 }
3175
3176 #endif //PRODUCT
3177
3178 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3179 st->print("a ");
3180 name()->print_value_on(st);
3181 obj->print_address_on(st);
3182 if (this == SystemDictionary::String_klass()
3183 && java_lang_String::value(obj) != NULL) {
3184 ResourceMark rm;
3185 int len = java_lang_String::length(obj);
3186 int plen = (len < 24 ? len : 12);
3187 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3188 st->print(" = \"%s\"", str);
3189 if (len > plen)
3190 st->print("...[%d]", len);
3191 } else if (this == SystemDictionary::Class_klass()) {
3192 Klass* k = java_lang_Class::as_Klass(obj);
3193 st->print(" = ");
3194 if (k != NULL) {
3195 k->print_value_on(st);
3196 } else {
3197 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3198 st->print("%s", tname ? tname : "type?");
3199 }
3200 } else if (this == SystemDictionary::MethodType_klass()) {
3201 st->print(" = ");
3202 java_lang_invoke_MethodType::print_signature(obj, st);
3203 } else if (java_lang_boxing_object::is_instance(obj)) {
3204 st->print(" = ");
3205 java_lang_boxing_object::print(obj, st);
3206 } else if (this == SystemDictionary::LambdaForm_klass()) {
3207 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3208 if (vmentry != NULL) {
3209 st->print(" => ");
3210 vmentry->print_value_on(st);
3211 }
3212 } else if (this == SystemDictionary::MemberName_klass()) {
3213 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3214 if (vmtarget != NULL) {
3215 st->print(" = ");
3216 vmtarget->print_value_on(st);
3217 } else {
3218 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3219 st->print(".");
3220 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3221 }
3222 }
3223 }
3224
3225 const char* InstanceKlass::internal_name() const {
3226 return external_name();
3227 }
3228
3229 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3230 const char* module_name,
3231 const ClassFileStream* cfs) const {
3232 if (!log_is_enabled(Info, class, load)) {
3233 return;
3234 }
3235
3236 ResourceMark rm;
3237 LogMessage(class, load) msg;
3238 stringStream info_stream;
3239
3240 // Name and class hierarchy info
3241 info_stream.print("%s", external_name());
3242
3243 // Source
3244 if (cfs != NULL) {
3245 if (cfs->source() != NULL) {
3246 if (module_name != NULL) {
3247 if (ClassLoader::is_modules_image(cfs->source())) {
3248 info_stream.print(" source: jrt:/%s", module_name);
3249 } else {
3250 info_stream.print(" source: %s", cfs->source());
3251 }
3252 } else {
3253 info_stream.print(" source: %s", cfs->source());
3254 }
3255 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3256 Thread* THREAD = Thread::current();
3257 Klass* caller =
3258 THREAD->is_Java_thread()
3259 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3260 : NULL;
3261 // caller can be NULL, for example, during a JVMTI VM_Init hook
3262 if (caller != NULL) {
3263 info_stream.print(" source: instance of %s", caller->external_name());
3264 } else {
3265 // source is unknown
3266 }
3267 } else {
3268 oop class_loader = loader_data->class_loader();
3269 info_stream.print(" source: %s", class_loader->klass()->external_name());
3270 }
3271 } else {
3272 info_stream.print(" source: shared objects file");
3273 }
3274
3275 msg.info("%s", info_stream.as_string());
3276
3277 if (log_is_enabled(Debug, class, load)) {
3278 stringStream debug_stream;
3279
3280 // Class hierarchy info
3281 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3282 p2i(this), p2i(superklass()));
3283
3284 // Interfaces
3285 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3286 debug_stream.print(" interfaces:");
3287 int length = local_interfaces()->length();
3288 for (int i = 0; i < length; i++) {
3289 debug_stream.print(" " INTPTR_FORMAT,
3290 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3291 }
3292 }
3293
3294 // Class loader
3295 debug_stream.print(" loader: [");
3296 loader_data->print_value_on(&debug_stream);
3297 debug_stream.print("]");
3298
3299 // Classfile checksum
3300 if (cfs) {
3301 debug_stream.print(" bytes: %d checksum: %08x",
3302 cfs->length(),
3303 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3304 cfs->length()));
3305 }
3306
3307 msg.debug("%s", debug_stream.as_string());
3308 }
3309 }
3310
3311 #if INCLUDE_SERVICES
3312 // Size Statistics
3313 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3314 Klass::collect_statistics(sz);
3315
3316 sz->_inst_size = wordSize * size_helper();
3317 sz->_vtab_bytes = wordSize * vtable_length();
3318 sz->_itab_bytes = wordSize * itable_length();
3319 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3320
3321 int n = 0;
3322 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3323 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3324 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3325 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3326 n += (sz->_fields_bytes = sz->count_array(fields()));
3327 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3328 sz->_ro_bytes += n;
3329
3330 const ConstantPool* cp = constants();
3331 if (cp) {
3332 cp->collect_statistics(sz);
3333 }
3334
3335 const Annotations* anno = annotations();
3336 if (anno) {
3337 anno->collect_statistics(sz);
3338 }
3339
3340 const Array<Method*>* methods_array = methods();
3341 if (methods()) {
3342 for (int i = 0; i < methods_array->length(); i++) {
3343 Method* method = methods_array->at(i);
3344 if (method) {
3345 sz->_method_count ++;
3346 method->collect_statistics(sz);
3347 }
3348 }
3349 }
3350 }
3351 #endif // INCLUDE_SERVICES
3352
3353 // Verification
3354
3355 class VerifyFieldClosure: public OopClosure {
3356 protected:
3357 template <class T> void do_oop_work(T* p) {
3358 oop obj = oopDesc::load_decode_heap_oop(p);
3359 if (!oopDesc::is_oop_or_null(obj)) {
3360 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3361 Universe::print_on(tty);
3362 guarantee(false, "boom");
3363 }
3364 }
3365 public:
3366 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3367 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3368 };
3369
3370 void InstanceKlass::verify_on(outputStream* st) {
3371 #ifndef PRODUCT
3372 // Avoid redundant verifies, this really should be in product.
3373 if (_verify_count == Universe::verify_count()) return;
3374 _verify_count = Universe::verify_count();
3375 #endif
3376
3377 // Verify Klass
3378 Klass::verify_on(st);
3379
3380 // Verify that klass is present in ClassLoaderData
3381 guarantee(class_loader_data()->contains_klass(this),
3382 "this class isn't found in class loader data");
3383
3384 // Verify vtables
3385 if (is_linked()) {
3386 // $$$ This used to be done only for m/s collections. Doing it
3387 // always seemed a valid generalization. (DLD -- 6/00)
3388 vtable().verify(st);
3389 }
3390
3391 // Verify first subklass
3392 if (subklass() != NULL) {
3393 guarantee(subklass()->is_klass(), "should be klass");
3394 }
3395
3396 // Verify siblings
3397 Klass* super = this->super();
3398 Klass* sib = next_sibling();
3399 if (sib != NULL) {
3400 if (sib == this) {
3401 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3402 }
3403
3404 guarantee(sib->is_klass(), "should be klass");
3405 guarantee(sib->super() == super, "siblings should have same superklass");
3406 }
3407
3408 // Verify implementor fields
3409 Klass* im = implementor();
3410 if (im != NULL) {
3411 guarantee(is_interface(), "only interfaces should have implementor set");
3412 guarantee(im->is_klass(), "should be klass");
3413 guarantee(!im->is_interface() || im == this,
3414 "implementors cannot be interfaces");
3415 }
3416
3417 // Verify local interfaces
3418 if (local_interfaces()) {
3419 Array<Klass*>* local_interfaces = this->local_interfaces();
3420 for (int j = 0; j < local_interfaces->length(); j++) {
3421 Klass* e = local_interfaces->at(j);
3422 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3423 }
3424 }
3425
3426 // Verify transitive interfaces
3427 if (transitive_interfaces() != NULL) {
3428 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3429 for (int j = 0; j < transitive_interfaces->length(); j++) {
3430 Klass* e = transitive_interfaces->at(j);
3431 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3432 }
3433 }
3434
3435 // Verify methods
3436 if (methods() != NULL) {
3437 Array<Method*>* methods = this->methods();
3438 for (int j = 0; j < methods->length(); j++) {
3439 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3440 }
3441 for (int j = 0; j < methods->length() - 1; j++) {
3442 Method* m1 = methods->at(j);
3443 Method* m2 = methods->at(j + 1);
3444 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3445 }
3446 }
3447
3448 // Verify method ordering
3449 if (method_ordering() != NULL) {
3450 Array<int>* method_ordering = this->method_ordering();
3451 int length = method_ordering->length();
3452 if (JvmtiExport::can_maintain_original_method_order() ||
3453 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3454 guarantee(length == methods()->length(), "invalid method ordering length");
3455 jlong sum = 0;
3456 for (int j = 0; j < length; j++) {
3457 int original_index = method_ordering->at(j);
3458 guarantee(original_index >= 0, "invalid method ordering index");
3459 guarantee(original_index < length, "invalid method ordering index");
3460 sum += original_index;
3461 }
3462 // Verify sum of indices 0,1,...,length-1
3463 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3464 } else {
3465 guarantee(length == 0, "invalid method ordering length");
3466 }
3467 }
3468
3469 // Verify default methods
3470 if (default_methods() != NULL) {
3471 Array<Method*>* methods = this->default_methods();
3472 for (int j = 0; j < methods->length(); j++) {
3473 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3474 }
3475 for (int j = 0; j < methods->length() - 1; j++) {
3476 Method* m1 = methods->at(j);
3477 Method* m2 = methods->at(j + 1);
3478 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3479 }
3480 }
3481
3482 // Verify JNI static field identifiers
3483 if (jni_ids() != NULL) {
3484 jni_ids()->verify(this);
3485 }
3486
3487 // Verify other fields
3488 if (array_klasses() != NULL) {
3489 guarantee(array_klasses()->is_klass(), "should be klass");
3490 }
3491 if (constants() != NULL) {
3492 guarantee(constants()->is_constantPool(), "should be constant pool");
3493 }
3494 const Klass* host = host_klass();
3495 if (host != NULL) {
3496 guarantee(host->is_klass(), "should be klass");
3497 }
3498 }
3499
3500 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3501 Klass::oop_verify_on(obj, st);
3502 VerifyFieldClosure blk;
3503 obj->oop_iterate_no_header(&blk);
3504 }
3505
3506
3507 // JNIid class for jfieldIDs only
3508 // Note to reviewers:
3509 // These JNI functions are just moved over to column 1 and not changed
3510 // in the compressed oops workspace.
3511 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3512 _holder = holder;
3513 _offset = offset;
3514 _next = next;
3515 debug_only(_is_static_field_id = false;)
3516 }
3517
3518
3519 JNIid* JNIid::find(int offset) {
3520 JNIid* current = this;
3521 while (current != NULL) {
3522 if (current->offset() == offset) return current;
3523 current = current->next();
3524 }
3525 return NULL;
3526 }
3527
3528 void JNIid::deallocate(JNIid* current) {
3529 while (current != NULL) {
3530 JNIid* next = current->next();
3531 delete current;
3532 current = next;
3533 }
3534 }
3535
3536
3537 void JNIid::verify(Klass* holder) {
3538 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3539 int end_field_offset;
3540 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3541
3542 JNIid* current = this;
3543 while (current != NULL) {
3544 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3545 #ifdef ASSERT
3546 int o = current->offset();
3547 if (current->is_static_field_id()) {
3548 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3549 }
3550 #endif
3551 current = current->next();
3552 }
3553 }
3554
3555 oop InstanceKlass::klass_holder_phantom() {
3556 oop* addr;
3557 if (is_anonymous()) {
3558 addr = _java_mirror.ptr_raw();
3559 } else {
3560 addr = &class_loader_data()->_class_loader;
3561 }
3562 return RootAccess<IN_CONCURRENT_ROOT | ON_PHANTOM_OOP_REF>::oop_load(addr);
3563 }
3564
3565 #ifdef ASSERT
3566 void InstanceKlass::set_init_state(ClassState state) {
3567 bool good_state = is_shared() ? (_init_state <= state)
3568 : (_init_state < state);
3569 assert(good_state || state == allocated, "illegal state transition");
3570 _init_state = (u1)state;
3571 }
3572 #endif
3573
3574 #if INCLUDE_JVMTI
3575
3576 // RedefineClasses() support for previous versions
3577
3578 // Globally, there is at least one previous version of a class to walk
3579 // during class unloading, which is saved because old methods in the class
3580 // are still running. Otherwise the previous version list is cleaned up.
3581 bool InstanceKlass::_has_previous_versions = false;
3582
3583 // Returns true if there are previous versions of a class for class
3584 // unloading only. Also resets the flag to false. purge_previous_version
3585 // will set the flag to true if there are any left, i.e., if there's any
3586 // work to do for next time. This is to avoid the expensive code cache
3587 // walk in CLDG::do_unloading().
3588 bool InstanceKlass::has_previous_versions_and_reset() {
3589 bool ret = _has_previous_versions;
3590 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3591 ret ? "true" : "false");
3592 _has_previous_versions = false;
3593 return ret;
3594 }
3595
3596 // Purge previous versions before adding new previous versions of the class and
3597 // during class unloading.
3598 void InstanceKlass::purge_previous_version_list() {
3599 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3600 assert(has_been_redefined(), "Should only be called for main class");
3601
3602 // Quick exit.
3603 if (previous_versions() == NULL) {
3604 return;
3605 }
3606
3607 // This klass has previous versions so see what we can cleanup
3608 // while it is safe to do so.
3609
3610 int deleted_count = 0; // leave debugging breadcrumbs
3611 int live_count = 0;
3612 ClassLoaderData* loader_data = class_loader_data();
3613 assert(loader_data != NULL, "should never be null");
3614
3615 ResourceMark rm;
3616 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3617
3618 // previous versions are linked together through the InstanceKlass
3619 InstanceKlass* pv_node = previous_versions();
3620 InstanceKlass* last = this;
3621 int version = 0;
3622
3623 // check the previous versions list
3624 for (; pv_node != NULL; ) {
3625
3626 ConstantPool* pvcp = pv_node->constants();
3627 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3628
3629 if (!pvcp->on_stack()) {
3630 // If the constant pool isn't on stack, none of the methods
3631 // are executing. Unlink this previous_version.
3632 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3633 // so will be deallocated during the next phase of class unloading.
3634 log_trace(redefine, class, iklass, purge)
3635 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3636 // For debugging purposes.
3637 pv_node->set_is_scratch_class();
3638 // Unlink from previous version list.
3639 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3640 InstanceKlass* next = pv_node->previous_versions();
3641 pv_node->link_previous_versions(NULL); // point next to NULL
3642 last->link_previous_versions(next);
3643 // Add to the deallocate list after unlinking
3644 loader_data->add_to_deallocate_list(pv_node);
3645 pv_node = next;
3646 deleted_count++;
3647 version++;
3648 continue;
3649 } else {
3650 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3651 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3652 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3653 live_count++;
3654 // found a previous version for next time we do class unloading
3655 _has_previous_versions = true;
3656 }
3657
3658 // At least one method is live in this previous version.
3659 // Reset dead EMCP methods not to get breakpoints.
3660 // All methods are deallocated when all of the methods for this class are no
3661 // longer running.
3662 Array<Method*>* method_refs = pv_node->methods();
3663 if (method_refs != NULL) {
3664 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3665 for (int j = 0; j < method_refs->length(); j++) {
3666 Method* method = method_refs->at(j);
3667
3668 if (!method->on_stack()) {
3669 // no breakpoints for non-running methods
3670 if (method->is_running_emcp()) {
3671 method->set_running_emcp(false);
3672 }
3673 } else {
3674 assert (method->is_obsolete() || method->is_running_emcp(),
3675 "emcp method cannot run after emcp bit is cleared");
3676 log_trace(redefine, class, iklass, purge)
3677 ("purge: %s(%s): prev method @%d in version @%d is alive",
3678 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3679 }
3680 }
3681 }
3682 // next previous version
3683 last = pv_node;
3684 pv_node = pv_node->previous_versions();
3685 version++;
3686 }
3687 log_trace(redefine, class, iklass, purge)
3688 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3689 }
3690
3691 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3692 int emcp_method_count) {
3693 int obsolete_method_count = old_methods->length() - emcp_method_count;
3694
3695 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3696 _previous_versions != NULL) {
3697 // We have a mix of obsolete and EMCP methods so we have to
3698 // clear out any matching EMCP method entries the hard way.
3699 int local_count = 0;
3700 for (int i = 0; i < old_methods->length(); i++) {
3701 Method* old_method = old_methods->at(i);
3702 if (old_method->is_obsolete()) {
3703 // only obsolete methods are interesting
3704 Symbol* m_name = old_method->name();
3705 Symbol* m_signature = old_method->signature();
3706
3707 // previous versions are linked together through the InstanceKlass
3708 int j = 0;
3709 for (InstanceKlass* prev_version = _previous_versions;
3710 prev_version != NULL;
3711 prev_version = prev_version->previous_versions(), j++) {
3712
3713 Array<Method*>* method_refs = prev_version->methods();
3714 for (int k = 0; k < method_refs->length(); k++) {
3715 Method* method = method_refs->at(k);
3716
3717 if (!method->is_obsolete() &&
3718 method->name() == m_name &&
3719 method->signature() == m_signature) {
3720 // The current RedefineClasses() call has made all EMCP
3721 // versions of this method obsolete so mark it as obsolete
3722 log_trace(redefine, class, iklass, add)
3723 ("%s(%s): flush obsolete method @%d in version @%d",
3724 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3725
3726 method->set_is_obsolete();
3727 break;
3728 }
3729 }
3730
3731 // The previous loop may not find a matching EMCP method, but
3732 // that doesn't mean that we can optimize and not go any
3733 // further back in the PreviousVersion generations. The EMCP
3734 // method for this generation could have already been made obsolete,
3735 // but there still may be an older EMCP method that has not
3736 // been made obsolete.
3737 }
3738
3739 if (++local_count >= obsolete_method_count) {
3740 // no more obsolete methods so bail out now
3741 break;
3742 }
3743 }
3744 }
3745 }
3746 }
3747
3748 // Save the scratch_class as the previous version if any of the methods are running.
3749 // The previous_versions are used to set breakpoints in EMCP methods and they are
3750 // also used to clean MethodData links to redefined methods that are no longer running.
3751 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3752 int emcp_method_count) {
3753 assert(Thread::current()->is_VM_thread(),
3754 "only VMThread can add previous versions");
3755
3756 ResourceMark rm;
3757 log_trace(redefine, class, iklass, add)
3758 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3759
3760 // Clean out old previous versions for this class
3761 purge_previous_version_list();
3762
3763 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3764 // a previous redefinition may be made obsolete by this redefinition.
3765 Array<Method*>* old_methods = scratch_class->methods();
3766 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3767
3768 // If the constant pool for this previous version of the class
3769 // is not marked as being on the stack, then none of the methods
3770 // in this previous version of the class are on the stack so
3771 // we don't need to add this as a previous version.
3772 ConstantPool* cp_ref = scratch_class->constants();
3773 if (!cp_ref->on_stack()) {
3774 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3775 // For debugging purposes.
3776 scratch_class->set_is_scratch_class();
3777 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3778 return;
3779 }
3780
3781 if (emcp_method_count != 0) {
3782 // At least one method is still running, check for EMCP methods
3783 for (int i = 0; i < old_methods->length(); i++) {
3784 Method* old_method = old_methods->at(i);
3785 if (!old_method->is_obsolete() && old_method->on_stack()) {
3786 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3787 // we can add breakpoints for it.
3788
3789 // We set the method->on_stack bit during safepoints for class redefinition
3790 // and use this bit to set the is_running_emcp bit.
3791 // After the safepoint, the on_stack bit is cleared and the running emcp
3792 // method may exit. If so, we would set a breakpoint in a method that
3793 // is never reached, but this won't be noticeable to the programmer.
3794 old_method->set_running_emcp(true);
3795 log_trace(redefine, class, iklass, add)
3796 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3797 } else if (!old_method->is_obsolete()) {
3798 log_trace(redefine, class, iklass, add)
3799 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3800 }
3801 }
3802 }
3803
3804 // Add previous version if any methods are still running.
3805 // Set has_previous_version flag for processing during class unloading.
3806 _has_previous_versions = true;
3807 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3808 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3809 scratch_class->link_previous_versions(previous_versions());
3810 link_previous_versions(scratch_class);
3811 } // end add_previous_version()
3812
3813 #endif // INCLUDE_JVMTI
3814
3815 Method* InstanceKlass::method_with_idnum(int idnum) {
3816 Method* m = NULL;
3817 if (idnum < methods()->length()) {
3818 m = methods()->at(idnum);
3819 }
3820 if (m == NULL || m->method_idnum() != idnum) {
3821 for (int index = 0; index < methods()->length(); ++index) {
3822 m = methods()->at(index);
3823 if (m->method_idnum() == idnum) {
3824 return m;
3825 }
3826 }
3827 // None found, return null for the caller to handle.
3828 return NULL;
3829 }
3830 return m;
3831 }
3832
3833
3834 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3835 if (idnum >= methods()->length()) {
3836 return NULL;
3837 }
3838 Method* m = methods()->at(idnum);
3839 if (m != NULL && m->orig_method_idnum() == idnum) {
3840 return m;
3841 }
3842 // Obsolete method idnum does not match the original idnum
3843 for (int index = 0; index < methods()->length(); ++index) {
3844 m = methods()->at(index);
3845 if (m->orig_method_idnum() == idnum) {
3846 return m;
3847 }
3848 }
3849 // None found, return null for the caller to handle.
3850 return NULL;
3851 }
3852
3853
3854 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3855 InstanceKlass* holder = get_klass_version(version);
3856 if (holder == NULL) {
3857 return NULL; // The version of klass is gone, no method is found
3858 }
3859 Method* method = holder->method_with_orig_idnum(idnum);
3860 return method;
3861 }
3862
3863 #if INCLUDE_JVMTI
3864 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3865 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3866 // Ignore the archived class stream data
3867 return NULL;
3868 } else {
3869 return _cached_class_file;
3870 }
3871 }
3872
3873 jint InstanceKlass::get_cached_class_file_len() {
3874 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3875 }
3876
3877 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3878 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3879 }
3880
3881 #if INCLUDE_CDS
3882 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3883 if (DumpSharedSpaces) {
3884 return _cached_class_file;
3885 } else {
3886 assert(this->is_shared(), "class should be shared");
3887 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3888 return _cached_class_file;
3889 } else {
3890 return NULL;
3891 }
3892 }
3893 }
3894 #endif
3895 #endif
3896
3897 #define THROW_DVT_ERROR(s) \
3898 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), \
3899 "ValueCapableClass class '%s' %s", external_name(),(s)); \
3900 return