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 static inline bool is_class_loader(const Symbol* class_name,
129 const ClassFileParser& parser) {
130 assert(class_name != NULL, "invariant");
131
132 if (class_name == vmSymbols::java_lang_ClassLoader()) {
133 return true;
134 }
135
136 if (SystemDictionary::ClassLoader_klass_loaded()) {
137 const Klass* const super_klass = parser.super_klass();
138 if (super_klass != NULL) {
139 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
140 return true;
141 }
142 }
143 }
144 return false;
145 }
146
147 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
148 const int size = InstanceKlass::size(parser.vtable_size(),
149 parser.itable_size(),
150 nonstatic_oop_map_size(parser.total_oop_map_count()),
151 parser.is_interface(),
152 parser.is_anonymous(),
153 should_store_fingerprint(parser.is_anonymous()),
154 parser.has_flattenable_fields() ? parser.java_fields_count() : 0,
155 parser.is_value_type());
156
157 const Symbol* const class_name = parser.class_name();
158 assert(class_name != NULL, "invariant");
159 ClassLoaderData* loader_data = parser.loader_data();
160 assert(loader_data != NULL, "invariant");
161
162 InstanceKlass* ik;
163
164 // Allocation
165 if (REF_NONE == parser.reference_type()) {
166 if (class_name == vmSymbols::java_lang_Class()) {
167 // mirror
168 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
169 } else if (is_class_loader(class_name, parser)) {
170 // class loader
171 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
172 } else if (parser.is_value_type()) {
173 // value type
174 ik = new (loader_data, size, THREAD) ValueKlass(parser);
175 } else {
176 // normal
177 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
178 }
179 } else {
180 // reference
181 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
182 }
183
184 // Check for pending exception before adding to the loader data and incrementing
185 // class count. Can get OOM here.
186 if (HAS_PENDING_EXCEPTION) {
187 return NULL;
188 }
189
190 assert(ik != NULL, "invariant");
191
192 const bool publicize = !parser.is_internal();
193 #ifdef ASSERT
194 assert(ik->size() == size, "");
195 ik->bounds_check((address) ik->start_of_vtable(), false, size);
196 ik->bounds_check((address) ik->start_of_itable(), false, size);
197 ik->bounds_check((address) ik->end_of_itable(), true, size);
198 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
199 #endif //ASSERT
200
201 // Add all classes to our internal class loader list here,
202 // including classes in the bootstrap (NULL) class loader.
203 loader_data->add_class(ik, publicize);
204 return ik;
205 }
206
207 #ifndef PRODUCT
208 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
209 const char* bad = NULL;
210 address end = NULL;
211 if (addr < (address)this) {
212 bad = "before";
213 } else if (addr == (address)this) {
214 if (edge_ok) return true;
215 bad = "just before";
216 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
217 if (edge_ok) return true;
218 bad = "just after";
219 } else if (addr > end) {
220 bad = "after";
221 } else {
222 return true;
223 }
224 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
225 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
226 Verbose = WizardMode = true; this->print(); //@@
227 return false;
228 }
229 #endif //PRODUCT
230
231 // copy method ordering from resource area to Metaspace
232 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
233 if (m != NULL) {
234 // allocate a new array and copy contents (memcpy?)
235 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
236 for (int i = 0; i < m->length(); i++) {
237 _method_ordering->at_put(i, m->at(i));
238 }
239 } else {
240 _method_ordering = Universe::the_empty_int_array();
241 }
242 }
243
244 // create a new array of vtable_indices for default methods
245 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
246 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
247 assert(default_vtable_indices() == NULL, "only create once");
248 set_default_vtable_indices(vtable_indices);
249 return vtable_indices;
250 }
251
252 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
253 _static_field_size(parser.static_field_size()),
254 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
255 _itable_len(parser.itable_size()),
256 _reference_type(parser.reference_type()),
257 _extra_flags(0),
258 _adr_valueklass_fixed_block(NULL) {
259 set_vtable_length(parser.vtable_size());
260 set_kind(kind);
261 set_access_flags(parser.access_flags());
262 set_is_anonymous(parser.is_anonymous());
263 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
264 false));
265 if (parser.has_flattenable_fields()) {
266 set_has_value_fields();
267 }
268 _java_fields_count = parser.java_fields_count();
269
270 assert(NULL == _methods, "underlying memory not zeroed?");
271 assert(is_instance_klass(), "is layout incorrect?");
272 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
273 }
274
275 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
276 Array<Method*>* methods) {
277 if (methods != NULL && methods != Universe::the_empty_method_array() &&
278 !methods->is_shared()) {
279 for (int i = 0; i < methods->length(); i++) {
280 Method* method = methods->at(i);
281 if (method == NULL) continue; // maybe null if error processing
282 // Only want to delete methods that are not executing for RedefineClasses.
283 // The previous version will point to them so they're not totally dangling
284 assert (!method->on_stack(), "shouldn't be called with methods on stack");
285 MetadataFactory::free_metadata(loader_data, method);
286 }
287 MetadataFactory::free_array<Method*>(loader_data, methods);
288 }
289 }
290
291 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
292 const Klass* super_klass,
293 Array<Klass*>* local_interfaces,
294 Array<Klass*>* transitive_interfaces) {
295 // Only deallocate transitive interfaces if not empty, same as super class
296 // or same as local interfaces. See code in parseClassFile.
297 Array<Klass*>* ti = transitive_interfaces;
298 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
299 // check that the interfaces don't come from super class
300 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
301 InstanceKlass::cast(super_klass)->transitive_interfaces();
302 if (ti != sti && ti != NULL && !ti->is_shared()) {
303 MetadataFactory::free_array<Klass*>(loader_data, ti);
304 }
305 }
306
307 // local interfaces can be empty
308 if (local_interfaces != Universe::the_empty_klass_array() &&
309 local_interfaces != NULL && !local_interfaces->is_shared()) {
310 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
311 }
312 }
313
314 // This function deallocates the metadata and C heap pointers that the
315 // InstanceKlass points to.
316 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
317
318 // Orphan the mirror first, CMS thinks it's still live.
319 if (java_mirror() != NULL) {
320 java_lang_Class::set_klass(java_mirror(), NULL);
321 }
322
323 // Also remove mirror from handles
324 loader_data->remove_handle(_java_mirror);
325
326 // Need to take this class off the class loader data list.
327 loader_data->remove_class(this);
328
329 // The array_klass for this class is created later, after error handling.
330 // For class redefinition, we keep the original class so this scratch class
331 // doesn't have an array class. Either way, assert that there is nothing
332 // to deallocate.
333 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
334
335 // Release C heap allocated data that this might point to, which includes
336 // reference counting symbol names.
337 release_C_heap_structures();
338
339 deallocate_methods(loader_data, methods());
340 set_methods(NULL);
341
342 if (method_ordering() != NULL &&
343 method_ordering() != Universe::the_empty_int_array() &&
344 !method_ordering()->is_shared()) {
345 MetadataFactory::free_array<int>(loader_data, method_ordering());
346 }
347 set_method_ordering(NULL);
348
349 // default methods can be empty
350 if (default_methods() != NULL &&
351 default_methods() != Universe::the_empty_method_array() &&
352 !default_methods()->is_shared()) {
353 MetadataFactory::free_array<Method*>(loader_data, default_methods());
354 }
355 // Do NOT deallocate the default methods, they are owned by superinterfaces.
356 set_default_methods(NULL);
357
358 // default methods vtable indices can be empty
359 if (default_vtable_indices() != NULL &&
360 !default_vtable_indices()->is_shared()) {
361 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
362 }
363 set_default_vtable_indices(NULL);
364
365
366 // This array is in Klass, but remove it with the InstanceKlass since
367 // this place would be the only caller and it can share memory with transitive
368 // interfaces.
369 if (secondary_supers() != NULL &&
370 secondary_supers() != Universe::the_empty_klass_array() &&
371 secondary_supers() != transitive_interfaces() &&
372 !secondary_supers()->is_shared()) {
373 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
374 }
375 set_secondary_supers(NULL);
376
377 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
378 set_transitive_interfaces(NULL);
379 set_local_interfaces(NULL);
380
381 if (fields() != NULL && !fields()->is_shared()) {
382 MetadataFactory::free_array<jushort>(loader_data, fields());
383 }
384 set_fields(NULL, 0);
385
386 // If a method from a redefined class is using this constant pool, don't
387 // delete it, yet. The new class's previous version will point to this.
388 if (constants() != NULL) {
389 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
390 if (!constants()->is_shared()) {
391 MetadataFactory::free_metadata(loader_data, constants());
392 }
393 // Delete any cached resolution errors for the constant pool
394 SystemDictionary::delete_resolution_error(constants());
395
396 set_constants(NULL);
397 }
398
399 if (inner_classes() != NULL &&
400 inner_classes() != Universe::the_empty_short_array() &&
401 !inner_classes()->is_shared()) {
402 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
403 }
404 set_inner_classes(NULL);
405
406 if (value_types() != NULL && !value_types()->is_shared()) {
407 MetadataFactory::free_array<ValueTypes>(loader_data, value_types());
408 }
409 set_value_types(NULL);
410
411 // We should deallocate the Annotations instance if it's not in shared spaces.
412 if (annotations() != NULL && !annotations()->is_shared()) {
413 MetadataFactory::free_metadata(loader_data, annotations());
414 }
415 set_annotations(NULL);
416 }
417
418 bool InstanceKlass::should_be_initialized() const {
419 return !is_initialized();
420 }
421
422 klassItable InstanceKlass::itable() const {
423 return klassItable(const_cast<InstanceKlass*>(this));
424 }
425
426 void InstanceKlass::eager_initialize(Thread *thread) {
427 if (!EagerInitialization) return;
428
429 if (this->is_not_initialized()) {
430 // abort if the the class has a class initializer
431 if (this->class_initializer() != NULL) return;
432
433 // abort if it is java.lang.Object (initialization is handled in genesis)
434 Klass* super_klass = super();
435 if (super_klass == NULL) return;
436
437 // abort if the super class should be initialized
438 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
439
440 // call body to expose the this pointer
441 eager_initialize_impl();
442 }
443 }
444
445 // JVMTI spec thinks there are signers and protection domain in the
446 // instanceKlass. These accessors pretend these fields are there.
447 // The hprof specification also thinks these fields are in InstanceKlass.
448 oop InstanceKlass::protection_domain() const {
449 // return the protection_domain from the mirror
450 return java_lang_Class::protection_domain(java_mirror());
451 }
452
453 // To remove these from requires an incompatible change and CCC request.
454 objArrayOop InstanceKlass::signers() const {
455 // return the signers from the mirror
456 return java_lang_Class::signers(java_mirror());
457 }
458
459 oop InstanceKlass::init_lock() const {
460 // return the init lock from the mirror
461 oop lock = java_lang_Class::init_lock(java_mirror());
462 // Prevent reordering with any access of initialization state
463 OrderAccess::loadload();
464 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
465 "only fully initialized state can have a null lock");
466 return lock;
467 }
468
469 // Set the initialization lock to null so the object can be GC'ed. Any racing
470 // threads to get this lock will see a null lock and will not lock.
471 // That's okay because they all check for initialized state after getting
472 // the lock and return.
473 void InstanceKlass::fence_and_clear_init_lock() {
474 // make sure previous stores are all done, notably the init_state.
475 OrderAccess::storestore();
476 java_lang_Class::set_init_lock(java_mirror(), NULL);
477 assert(!is_not_initialized(), "class must be initialized now");
478 }
479
480 void InstanceKlass::eager_initialize_impl() {
481 EXCEPTION_MARK;
482 HandleMark hm(THREAD);
483 Handle h_init_lock(THREAD, init_lock());
484 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
485
486 // abort if someone beat us to the initialization
487 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
488
489 ClassState old_state = init_state();
490 link_class_impl(true, THREAD);
491 if (HAS_PENDING_EXCEPTION) {
492 CLEAR_PENDING_EXCEPTION;
493 // Abort if linking the class throws an exception.
494
495 // Use a test to avoid redundantly resetting the state if there's
496 // no change. Set_init_state() asserts that state changes make
497 // progress, whereas here we might just be spinning in place.
498 if (old_state != _init_state)
499 set_init_state(old_state);
500 } else {
501 // linking successfull, mark class as initialized
502 set_init_state(fully_initialized);
503 fence_and_clear_init_lock();
504 // trace
505 if (log_is_enabled(Info, class, init)) {
506 ResourceMark rm(THREAD);
507 log_info(class, init)("[Initialized %s without side effects]", external_name());
508 }
509 }
510 }
511
512
513 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
514 // process. The step comments refers to the procedure described in that section.
515 // Note: implementation moved to static method to expose the this pointer.
516 void InstanceKlass::initialize(TRAPS) {
517 if (this->should_be_initialized()) {
518 initialize_impl(CHECK);
519 // Note: at this point the class may be initialized
520 // OR it may be in the state of being initialized
521 // in case of recursive initialization!
522 } else {
523 assert(is_initialized(), "sanity check");
524 }
525 }
526
527
528 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
529 // 1) Verify the bytecodes
530 Verifier::Mode mode =
531 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
532 return Verifier::verify(this, mode, should_verify_class(), THREAD);
533 }
534
535
536 // Used exclusively by the shared spaces dump mechanism to prevent
537 // classes mapped into the shared regions in new VMs from appearing linked.
538
539 void InstanceKlass::unlink_class() {
540 assert(is_linked(), "must be linked");
541 _init_state = loaded;
542 }
543
544 void InstanceKlass::link_class(TRAPS) {
545 assert(is_loaded(), "must be loaded");
546 if (!is_linked()) {
547 link_class_impl(true, CHECK);
548 }
549 }
550
551 // Called to verify that a class can link during initialization, without
552 // throwing a VerifyError.
553 bool InstanceKlass::link_class_or_fail(TRAPS) {
554 assert(is_loaded(), "must be loaded");
555 if (!is_linked()) {
556 link_class_impl(false, CHECK_false);
557 }
558 return is_linked();
559 }
560
561 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
562 if (DumpSharedSpaces && is_in_error_state()) {
563 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
564 // the class has failed verification. Throwing the NoClassDefFoundError here is just
565 // a convenient way to stop repeat attempts to verify the same (bad) class.
566 //
567 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
568 // if we are executing Java code. This is not a problem for CDS dumping phase since
569 // it doesn't execute any Java code.
570 ResourceMark rm(THREAD);
571 Exceptions::fthrow(THREAD_AND_LOCATION,
572 vmSymbols::java_lang_NoClassDefFoundError(),
573 "Class %s, or one of its supertypes, failed class initialization",
574 external_name());
575 return false;
576 }
577 // return if already verified
578 if (is_linked()) {
579 return true;
580 }
581
582 // Timing
583 // timer handles recursion
584 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
585 JavaThread* jt = (JavaThread*)THREAD;
586
587 // link super class before linking this class
588 Klass* super_klass = super();
589 if (super_klass != NULL) {
590 if (super_klass->is_interface()) { // check if super class is an interface
591 ResourceMark rm(THREAD);
592 Exceptions::fthrow(
593 THREAD_AND_LOCATION,
594 vmSymbols::java_lang_IncompatibleClassChangeError(),
595 "class %s has interface %s as super class",
596 external_name(),
597 super_klass->external_name()
598 );
599 return false;
600 }
601
602 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
603 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
604 }
605
606 // link all interfaces implemented by this class before linking this class
607 Array<Klass*>* interfaces = local_interfaces();
608 int num_interfaces = interfaces->length();
609 for (int index = 0; index < num_interfaces; index++) {
610 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
611 interk->link_class_impl(throw_verifyerror, CHECK_false);
612 }
613
614 // If a value type is referenced by a class (either as a field type or a
615 // method argument or return type) this value type must be loaded during
616 // the linking of this class because size and properties of the value type
617 // must be known in order to be able to perform value type optimizations
618
619 // Note: circular dependencies between value types are not handled yet
620
621 // Note: one case is not handled yet: arrays of value types => FixMe
622
623 // Note: the current implementation is not optimized because the search for
624 // value types is performed on all classes. It would be more efficient to
625 // detect value types during verification and 'tag' the classes for which
626 // value type loading is required. However, this optimization won't be
627 // applicable to classes that are not verified
628
629 // First step: fields
630 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
631 ResourceMark rm(THREAD);
632 if (fs.field_descriptor().access_flags().is_flattenable()) {
633 Symbol* signature = fs.field_descriptor().signature();
634 ResourceMark rm;
635 Symbol* name = SymbolTable::lookup(signature->as_C_string() + 1,
636 signature->utf8_length() - 2, CHECK_false);
637 assert(this->is_declared_value_type(name), "Verifying consistency with ValueTypes attribute");
638 name->decrement_refcount();
639 name = NULL;
640 // Get current loader and protection domain first.
641 oop loader = class_loader();
642 oop prot_domain = protection_domain();
643 Klass* klass = SystemDictionary::resolve_or_fail(signature,
644 Handle(THREAD, loader), Handle(THREAD, prot_domain), true,
645 CHECK_false);
646 if (klass == NULL) {
647 THROW_(vmSymbols::java_lang_LinkageError(), false);
648 }
649 }
650 }
651
652 // Second step: methods arguments and return types
653 for (int i = 0; i < constants()->length(); i++) {
654 if (constants()->tag_at(i).is_method()) {
655 Symbol* signature = constants()->uncached_signature_ref_at(i);
656 ResourceMark rm(THREAD);
657 for (SignatureStream ss(signature); !ss.is_done(); ss.next()) {
658 Symbol* sig = ss.as_symbol(THREAD);
659 if (is_declared_value_type(sig)) {
660 // Get current loader and protection domain first.
661 oop loader = class_loader();
662 oop protection_domain = this->protection_domain();
663
664 bool ok = SystemDictionary::resolve_or_fail(sig,
665 Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
666 CHECK_false);
667 if (!ok) {
668 THROW_(vmSymbols::java_lang_LinkageError(), false);
669 }
670 }
671 }
672 }
673 }
674
675 // in case the class is linked in the process of linking its superclasses
676 if (is_linked()) {
677 return true;
678 }
679
680 // trace only the link time for this klass that includes
681 // the verification time
682 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
683 ClassLoader::perf_class_link_selftime(),
684 ClassLoader::perf_classes_linked(),
685 jt->get_thread_stat()->perf_recursion_counts_addr(),
686 jt->get_thread_stat()->perf_timers_addr(),
687 PerfClassTraceTime::CLASS_LINK);
688
689 // verification & rewriting
690 {
691 HandleMark hm(THREAD);
692 Handle h_init_lock(THREAD, init_lock());
693 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
694 // rewritten will have been set if loader constraint error found
695 // on an earlier link attempt
696 // don't verify or rewrite if already rewritten
697 //
698
699 if (!is_linked()) {
700 if (!is_rewritten()) {
701 {
702 bool verify_ok = verify_code(throw_verifyerror, THREAD);
703 if (!verify_ok) {
704 return false;
705 }
706 }
707
708 // Just in case a side-effect of verify linked this class already
709 // (which can sometimes happen since the verifier loads classes
710 // using custom class loaders, which are free to initialize things)
711 if (is_linked()) {
712 return true;
713 }
714
715 // also sets rewritten
716 rewrite_class(CHECK_false);
717 } else if (is_shared()) {
718 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
719 }
720
721 // relocate jsrs and link methods after they are all rewritten
722 link_methods(CHECK_false);
723
724 // Initialize the vtable and interface table after
725 // methods have been rewritten since rewrite may
726 // fabricate new Method*s.
727 // also does loader constraint checking
728 //
729 // initialize_vtable and initialize_itable need to be rerun for
730 // a shared class if the class is not loaded by the NULL classloader.
731 ClassLoaderData * loader_data = class_loader_data();
732 if (!(is_shared() &&
733 loader_data->is_the_null_class_loader_data())) {
734 ResourceMark rm(THREAD);
735 vtable().initialize_vtable(true, CHECK_false);
736 itable().initialize_itable(true, CHECK_false);
737 }
738 #ifdef ASSERT
739 else {
740 vtable().verify(tty, true);
741 // In case itable verification is ever added.
742 // itable().verify(tty, true);
743 }
744 #endif
745
746 set_init_state(linked);
747 if (JvmtiExport::should_post_class_prepare()) {
748 Thread *thread = THREAD;
749 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
750 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
751 }
752 }
753 }
754 return true;
755 }
756
757
758 // Rewrite the byte codes of all of the methods of a class.
759 // The rewriter must be called exactly once. Rewriting must happen after
760 // verification but before the first method of the class is executed.
761 void InstanceKlass::rewrite_class(TRAPS) {
762 assert(is_loaded(), "must be loaded");
763 if (is_rewritten()) {
764 assert(is_shared(), "rewriting an unshared class?");
765 return;
766 }
767 Rewriter::rewrite(this, CHECK);
768 set_rewritten();
769 }
770
771 // Now relocate and link method entry points after class is rewritten.
772 // This is outside is_rewritten flag. In case of an exception, it can be
773 // executed more than once.
774 void InstanceKlass::link_methods(TRAPS) {
775 int len = methods()->length();
776 for (int i = len-1; i >= 0; i--) {
777 methodHandle m(THREAD, methods()->at(i));
778
779 // Set up method entry points for compiler and interpreter .
780 m->link_method(m, CHECK);
781 }
782 }
783
784 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
785 void InstanceKlass::initialize_super_interfaces(TRAPS) {
786 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
787 for (int i = 0; i < local_interfaces()->length(); ++i) {
788 Klass* iface = local_interfaces()->at(i);
789 InstanceKlass* ik = InstanceKlass::cast(iface);
790
791 // Initialization is depth first search ie. we start with top of the inheritance tree
792 // has_nonstatic_concrete_methods drives searching superinterfaces since it
793 // means has_nonstatic_concrete_methods in its superinterface hierarchy
794 if (ik->has_nonstatic_concrete_methods()) {
795 ik->initialize_super_interfaces(CHECK);
796 }
797
798 // Only initialize() interfaces that "declare" concrete methods.
799 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
800 ik->initialize(CHECK);
801 }
802 }
803 }
804
805 void InstanceKlass::initialize_impl(TRAPS) {
806 HandleMark hm(THREAD);
807
808 // Make sure klass is linked (verified) before initialization
809 // A class could already be verified, since it has been reflected upon.
810 link_class(CHECK);
811
812 DTRACE_CLASSINIT_PROBE(required, -1);
813
814 bool wait = false;
815
816 // refer to the JVM book page 47 for description of steps
817 // Step 1
818 {
819 Handle h_init_lock(THREAD, init_lock());
820 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
821
822 Thread *self = THREAD; // it's passed the current thread
823
824 // Step 2
825 // If we were to use wait() instead of waitInterruptibly() then
826 // we might end up throwing IE from link/symbol resolution sites
827 // that aren't expected to throw. This would wreak havoc. See 6320309.
828 while(is_being_initialized() && !is_reentrant_initialization(self)) {
829 wait = true;
830 ol.waitUninterruptibly(CHECK);
831 }
832
833 // Step 3
834 if (is_being_initialized() && is_reentrant_initialization(self)) {
835 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
836 return;
837 }
838
839 // Step 4
840 if (is_initialized()) {
841 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
842 return;
843 }
844
845 // Step 5
846 if (is_in_error_state()) {
847 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
848 ResourceMark rm(THREAD);
849 const char* desc = "Could not initialize class ";
850 const char* className = external_name();
851 size_t msglen = strlen(desc) + strlen(className) + 1;
852 char* message = NEW_RESOURCE_ARRAY(char, msglen);
853 if (NULL == message) {
854 // Out of memory: can't create detailed error message
855 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
856 } else {
857 jio_snprintf(message, msglen, "%s%s", desc, className);
858 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
859 }
860 }
861
862 // Step 6
863 set_init_state(being_initialized);
864 set_init_thread(self);
865 }
866
867 // Step 7
868 // Next, if C is a class rather than an interface, initialize it's super class and super
869 // interfaces.
870 if (!is_interface()) {
871 Klass* super_klass = super();
872 if (super_klass != NULL && super_klass->should_be_initialized()) {
873 super_klass->initialize(THREAD);
874 }
875 // If C implements any interface that declares a non-static, concrete method,
876 // the initialization of C triggers initialization of its super interfaces.
877 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
878 // having a superinterface that declares, non-static, concrete methods
879 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
880 initialize_super_interfaces(THREAD);
881 }
882
883 // If any exceptions, complete abruptly, throwing the same exception as above.
884 if (HAS_PENDING_EXCEPTION) {
885 Handle e(THREAD, PENDING_EXCEPTION);
886 CLEAR_PENDING_EXCEPTION;
887 {
888 EXCEPTION_MARK;
889 // Locks object, set state, and notify all waiting threads
890 set_initialization_state_and_notify(initialization_error, THREAD);
891 CLEAR_PENDING_EXCEPTION;
892 }
893 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
894 THROW_OOP(e());
895 }
896 }
897
898 // Step 8
899 // Initialize classes of flattenable fields
900 {
901 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
902 if (fs.is_flattenable()) {
903 InstanceKlass* field_klass = InstanceKlass::cast(this->get_value_field_klass(fs.index()));
904 field_klass->initialize(CHECK);
905 }
906 }
907 }
908
909
910 // Look for aot compiled methods for this klass, including class initializer.
911 AOTLoader::load_for_klass(this, THREAD);
912
913 // Step 9
914 {
915 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
916 JavaThread* jt = (JavaThread*)THREAD;
917 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
918 // Timer includes any side effects of class initialization (resolution,
919 // etc), but not recursive entry into call_class_initializer().
920 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
921 ClassLoader::perf_class_init_selftime(),
922 ClassLoader::perf_classes_inited(),
923 jt->get_thread_stat()->perf_recursion_counts_addr(),
924 jt->get_thread_stat()->perf_timers_addr(),
925 PerfClassTraceTime::CLASS_CLINIT);
926 call_class_initializer(THREAD);
927 }
928
929 // Step 10
930 if (!HAS_PENDING_EXCEPTION) {
931 set_initialization_state_and_notify(fully_initialized, CHECK);
932 {
933 debug_only(vtable().verify(tty, true);)
934 }
935 }
936 else {
937 // Step 11 and 12
938 Handle e(THREAD, PENDING_EXCEPTION);
939 CLEAR_PENDING_EXCEPTION;
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 EXCEPTION_MARK;
945 set_initialization_state_and_notify(initialization_error, THREAD);
946 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
947 // JVMTI has already reported the pending exception
948 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
949 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
950 }
951 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
952 if (e->is_a(SystemDictionary::Error_klass())) {
953 THROW_OOP(e());
954 } else {
955 JavaCallArguments args(e);
956 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
957 vmSymbols::throwable_void_signature(),
958 &args);
959 }
960 }
961 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
962 }
963
964
965 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
966 Handle h_init_lock(THREAD, init_lock());
967 if (h_init_lock() != NULL) {
968 ObjectLocker ol(h_init_lock, THREAD);
969 set_init_state(state);
970 fence_and_clear_init_lock();
971 ol.notify_all(CHECK);
972 } else {
973 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
974 set_init_state(state);
975 }
976 }
977
978 // The embedded _implementor field can only record one implementor.
979 // When there are more than one implementors, the _implementor field
980 // is set to the interface Klass* itself. Following are the possible
981 // values for the _implementor field:
982 // NULL - no implementor
983 // implementor Klass* - one implementor
984 // self - more than one implementor
985 //
986 // The _implementor field only exists for interfaces.
987 void InstanceKlass::add_implementor(Klass* k) {
988 assert(Compile_lock->owned_by_self(), "");
989 assert(is_interface(), "not interface");
990 // Filter out my subinterfaces.
991 // (Note: Interfaces are never on the subklass list.)
992 if (InstanceKlass::cast(k)->is_interface()) return;
993
994 // Filter out subclasses whose supers already implement me.
995 // (Note: CHA must walk subclasses of direct implementors
996 // in order to locate indirect implementors.)
997 Klass* sk = k->super();
998 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
999 // We only need to check one immediate superclass, since the
1000 // implements_interface query looks at transitive_interfaces.
1001 // Any supers of the super have the same (or fewer) transitive_interfaces.
1002 return;
1003
1004 Klass* ik = implementor();
1005 if (ik == NULL) {
1006 set_implementor(k);
1007 } else if (ik != this) {
1008 // There is already an implementor. Use itself as an indicator of
1009 // more than one implementors.
1010 set_implementor(this);
1011 }
1012
1013 // The implementor also implements the transitive_interfaces
1014 for (int index = 0; index < local_interfaces()->length(); index++) {
1015 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1016 }
1017 }
1018
1019 void InstanceKlass::init_implementor() {
1020 if (is_interface()) {
1021 set_implementor(NULL);
1022 }
1023 }
1024
1025
1026 void InstanceKlass::process_interfaces(Thread *thread) {
1027 // link this class into the implementors list of every interface it implements
1028 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1029 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1030 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1031 assert(interf->is_interface(), "expected interface");
1032 interf->add_implementor(this);
1033 }
1034 }
1035
1036 bool InstanceKlass::can_be_primary_super_slow() const {
1037 if (is_interface())
1038 return false;
1039 else
1040 return Klass::can_be_primary_super_slow();
1041 }
1042
1043 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1044 // The secondaries are the implemented interfaces.
1045 Array<Klass*>* interfaces = transitive_interfaces();
1046 int num_secondaries = num_extra_slots + interfaces->length();
1047 if (num_secondaries == 0) {
1048 // Must share this for correct bootstrapping!
1049 set_secondary_supers(Universe::the_empty_klass_array());
1050 return NULL;
1051 } else if (num_extra_slots == 0) {
1052 // The secondary super list is exactly the same as the transitive interfaces.
1053 // Redefine classes has to be careful not to delete this!
1054 set_secondary_supers(interfaces);
1055 return NULL;
1056 } else {
1057 // Copy transitive interfaces to a temporary growable array to be constructed
1058 // into the secondary super list with extra slots.
1059 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1060 for (int i = 0; i < interfaces->length(); i++) {
1061 secondaries->push(interfaces->at(i));
1062 }
1063 return secondaries;
1064 }
1065 }
1066
1067 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1068 if (k->is_interface()) {
1069 return implements_interface(k);
1070 } else {
1071 return Klass::compute_is_subtype_of(k);
1072 }
1073 }
1074
1075 bool InstanceKlass::implements_interface(Klass* k) const {
1076 if (this == k) return true;
1077 assert(k->is_interface(), "should be an interface class");
1078 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1079 if (transitive_interfaces()->at(i) == k) {
1080 return true;
1081 }
1082 }
1083 return false;
1084 }
1085
1086 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1087 // Verify direct super interface
1088 if (this == k) return true;
1089 assert(k->is_interface(), "should be an interface class");
1090 for (int i = 0; i < local_interfaces()->length(); i++) {
1091 if (local_interfaces()->at(i) == k) {
1092 return true;
1093 }
1094 }
1095 return false;
1096 }
1097
1098 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1099 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1100 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1101 report_java_out_of_memory("Requested array size exceeds VM limit");
1102 JvmtiExport::post_array_size_exhausted();
1103 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1104 }
1105 int size = objArrayOopDesc::object_size(length);
1106 Klass* ak = array_klass(n, CHECK_NULL);
1107 objArrayOop o =
1108 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1109 return o;
1110 }
1111
1112 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1113 if (TraceFinalizerRegistration) {
1114 tty->print("Registered ");
1115 i->print_value_on(tty);
1116 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1117 }
1118 instanceHandle h_i(THREAD, i);
1119 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1120 JavaValue result(T_VOID);
1121 JavaCallArguments args(h_i);
1122 methodHandle mh (THREAD, Universe::finalizer_register_method());
1123 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1124 return h_i();
1125 }
1126
1127 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1128 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1129 int size = size_helper(); // Query before forming handle.
1130
1131 instanceOop i;
1132
1133 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1134 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1135 i = register_finalizer(i, CHECK_NULL);
1136 }
1137 return i;
1138 }
1139
1140 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1141 if (is_interface() || is_abstract()) {
1142 ResourceMark rm(THREAD);
1143 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1144 : vmSymbols::java_lang_InstantiationException(), external_name());
1145 }
1146 if (this == SystemDictionary::Class_klass()) {
1147 ResourceMark rm(THREAD);
1148 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1149 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1150 }
1151 }
1152
1153 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1154 // Need load-acquire for lock-free read
1155 if (array_klasses_acquire() == NULL) {
1156 if (or_null) return NULL;
1157
1158 ResourceMark rm;
1159 JavaThread *jt = (JavaThread *)THREAD;
1160 {
1161 // Atomic creation of array_klasses
1162 MutexLocker mc(Compile_lock, THREAD); // for vtables
1163 MutexLocker ma(MultiArray_lock, THREAD);
1164
1165 // Check if update has already taken place
1166 if (array_klasses() == NULL) {
1167 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1168 // use 'release' to pair with lock-free load
1169 release_set_array_klasses(k);
1170 }
1171 }
1172 }
1173 // _this will always be set at this point
1174 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1175 if (or_null) {
1176 return oak->array_klass_or_null(n);
1177 }
1178 return oak->array_klass(n, THREAD);
1179 }
1180
1181 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1182 return array_klass_impl(or_null, 1, THREAD);
1183 }
1184
1185 static int call_class_initializer_counter = 0; // for debugging
1186
1187 Method* InstanceKlass::class_initializer() const {
1188 Method* clinit = find_method(
1189 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1190 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1191 return clinit;
1192 }
1193 return NULL;
1194 }
1195
1196 void InstanceKlass::call_class_initializer(TRAPS) {
1197 if (ReplayCompiles &&
1198 (ReplaySuppressInitializers == 1 ||
1199 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1200 // Hide the existence of the initializer for the purpose of replaying the compile
1201 return;
1202 }
1203
1204 methodHandle h_method(THREAD, class_initializer());
1205 assert(!is_initialized(), "we cannot initialize twice");
1206 LogTarget(Info, class, init) lt;
1207 if (lt.is_enabled()) {
1208 ResourceMark rm;
1209 LogStream ls(lt);
1210 ls.print("%d Initializing ", call_class_initializer_counter++);
1211 name()->print_value_on(&ls);
1212 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1213 }
1214 if (h_method() != NULL) {
1215 JavaCallArguments args; // No arguments
1216 JavaValue result(T_VOID);
1217 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1218 }
1219 }
1220
1221
1222 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1223 InterpreterOopMap* entry_for) {
1224 // Lazily create the _oop_map_cache at first request
1225 // Lock-free access requires load_acquire.
1226 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1227 if (oop_map_cache == NULL) {
1228 MutexLockerEx x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1229 // Check if _oop_map_cache was allocated while we were waiting for this lock
1230 if ((oop_map_cache = _oop_map_cache) == NULL) {
1231 oop_map_cache = new OopMapCache();
1232 // Ensure _oop_map_cache is stable, since it is examined without a lock
1233 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1234 }
1235 }
1236 // _oop_map_cache is constant after init; lookup below does its own locking.
1237 oop_map_cache->lookup(method, bci, entry_for);
1238 }
1239
1240
1241 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1242 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1243 Symbol* f_name = fs.name();
1244 Symbol* f_sig = fs.signature();
1245 if (f_name == name && f_sig == sig) {
1246 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1247 return true;
1248 }
1249 }
1250 return false;
1251 }
1252
1253
1254 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1255 const int n = local_interfaces()->length();
1256 for (int i = 0; i < n; i++) {
1257 Klass* intf1 = local_interfaces()->at(i);
1258 assert(intf1->is_interface(), "just checking type");
1259 // search for field in current interface
1260 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1261 assert(fd->is_static(), "interface field must be static");
1262 return intf1;
1263 }
1264 // search for field in direct superinterfaces
1265 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1266 if (intf2 != NULL) return intf2;
1267 }
1268 // otherwise field lookup fails
1269 return NULL;
1270 }
1271
1272
1273 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1274 // search order according to newest JVM spec (5.4.3.2, p.167).
1275 // 1) search for field in current klass
1276 if (find_local_field(name, sig, fd)) {
1277 return const_cast<InstanceKlass*>(this);
1278 }
1279 // 2) search for field recursively in direct superinterfaces
1280 { Klass* intf = find_interface_field(name, sig, fd);
1281 if (intf != NULL) return intf;
1282 }
1283 // 3) apply field lookup recursively if superclass exists
1284 { Klass* supr = super();
1285 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1286 }
1287 // 4) otherwise field lookup fails
1288 return NULL;
1289 }
1290
1291
1292 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1293 // search order according to newest JVM spec (5.4.3.2, p.167).
1294 // 1) search for field in current klass
1295 if (find_local_field(name, sig, fd)) {
1296 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1297 }
1298 // 2) search for field recursively in direct superinterfaces
1299 if (is_static) {
1300 Klass* intf = find_interface_field(name, sig, fd);
1301 if (intf != NULL) return intf;
1302 }
1303 // 3) apply field lookup recursively if superclass exists
1304 { Klass* supr = super();
1305 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1306 }
1307 // 4) otherwise field lookup fails
1308 return NULL;
1309 }
1310
1311
1312 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1313 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1314 if (fs.offset() == offset) {
1315 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1316 if (fd->is_static() == is_static) return true;
1317 }
1318 }
1319 return false;
1320 }
1321
1322
1323 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1324 Klass* klass = const_cast<InstanceKlass*>(this);
1325 while (klass != NULL) {
1326 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1327 return true;
1328 }
1329 klass = klass->super();
1330 }
1331 return false;
1332 }
1333
1334
1335 void InstanceKlass::methods_do(void f(Method* method)) {
1336 // Methods aren't stable until they are loaded. This can be read outside
1337 // a lock through the ClassLoaderData for profiling
1338 if (!is_loaded()) {
1339 return;
1340 }
1341
1342 int len = methods()->length();
1343 for (int index = 0; index < len; index++) {
1344 Method* m = methods()->at(index);
1345 assert(m->is_method(), "must be method");
1346 f(m);
1347 }
1348 }
1349
1350
1351 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1352 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1353 if (fs.access_flags().is_static()) {
1354 fieldDescriptor& fd = fs.field_descriptor();
1355 cl->do_field(&fd);
1356 }
1357 }
1358 }
1359
1360
1361 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1362 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1363 if (fs.access_flags().is_static()) {
1364 fieldDescriptor& fd = fs.field_descriptor();
1365 f(&fd, mirror, CHECK);
1366 }
1367 }
1368 }
1369
1370
1371 static int compare_fields_by_offset(int* a, int* b) {
1372 return a[0] - b[0];
1373 }
1374
1375 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1376 InstanceKlass* super = superklass();
1377 if (super != NULL) {
1378 super->do_nonstatic_fields(cl);
1379 }
1380 fieldDescriptor fd;
1381 int length = java_fields_count();
1382 // In DebugInfo nonstatic fields are sorted by offset.
1383 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1384 int j = 0;
1385 for (int i = 0; i < length; i += 1) {
1386 fd.reinitialize(this, i);
1387 if (!fd.is_static()) {
1388 fields_sorted[j + 0] = fd.offset();
1389 fields_sorted[j + 1] = i;
1390 j += 2;
1391 }
1392 }
1393 if (j > 0) {
1394 length = j;
1395 // _sort_Fn is defined in growableArray.hpp.
1396 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1397 for (int i = 0; i < length; i += 2) {
1398 fd.reinitialize(this, fields_sorted[i + 1]);
1399 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1400 cl->do_field(&fd);
1401 }
1402 }
1403 FREE_C_HEAP_ARRAY(int, fields_sorted);
1404 }
1405
1406
1407 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1408 if (array_klasses() != NULL)
1409 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1410 }
1411
1412 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1413 if (array_klasses() != NULL)
1414 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1415 }
1416
1417 #ifdef ASSERT
1418 static int linear_search(const Array<Method*>* methods,
1419 const Symbol* name,
1420 const Symbol* signature) {
1421 const int len = methods->length();
1422 for (int index = 0; index < len; index++) {
1423 const Method* const m = methods->at(index);
1424 assert(m->is_method(), "must be method");
1425 if (m->signature() == signature && m->name() == name) {
1426 return index;
1427 }
1428 }
1429 return -1;
1430 }
1431 #endif
1432
1433 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1434 int len = methods->length();
1435 // methods are sorted, so do binary search
1436 int l = 0;
1437 int h = len - 1;
1438 while (l <= h) {
1439 int mid = (l + h) >> 1;
1440 Method* m = methods->at(mid);
1441 assert(m->is_method(), "must be method");
1442 int res = m->name()->fast_compare(name);
1443 if (res == 0) {
1444 return mid;
1445 } else if (res < 0) {
1446 l = mid + 1;
1447 } else {
1448 h = mid - 1;
1449 }
1450 }
1451 return -1;
1452 }
1453
1454 // find_method looks up the name/signature in the local methods array
1455 Method* InstanceKlass::find_method(const Symbol* name,
1456 const Symbol* signature) const {
1457 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1458 }
1459
1460 Method* InstanceKlass::find_method_impl(const Symbol* name,
1461 const Symbol* signature,
1462 OverpassLookupMode overpass_mode,
1463 StaticLookupMode static_mode,
1464 PrivateLookupMode private_mode) const {
1465 return InstanceKlass::find_method_impl(methods(),
1466 name,
1467 signature,
1468 overpass_mode,
1469 static_mode,
1470 private_mode);
1471 }
1472
1473 // find_instance_method looks up the name/signature in the local methods array
1474 // and skips over static methods
1475 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1476 const Symbol* name,
1477 const Symbol* signature) {
1478 Method* const meth = InstanceKlass::find_method_impl(methods,
1479 name,
1480 signature,
1481 find_overpass,
1482 skip_static,
1483 find_private);
1484 assert(((meth == NULL) || !meth->is_static()),
1485 "find_instance_method should have skipped statics");
1486 return meth;
1487 }
1488
1489 // find_instance_method looks up the name/signature in the local methods array
1490 // and skips over static methods
1491 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1492 return InstanceKlass::find_instance_method(methods(), name, signature);
1493 }
1494
1495 // Find looks up the name/signature in the local methods array
1496 // and filters on the overpass, static and private flags
1497 // This returns the first one found
1498 // note that the local methods array can have up to one overpass, one static
1499 // and one instance (private or not) with the same name/signature
1500 Method* InstanceKlass::find_local_method(const Symbol* name,
1501 const Symbol* signature,
1502 OverpassLookupMode overpass_mode,
1503 StaticLookupMode static_mode,
1504 PrivateLookupMode private_mode) const {
1505 return InstanceKlass::find_method_impl(methods(),
1506 name,
1507 signature,
1508 overpass_mode,
1509 static_mode,
1510 private_mode);
1511 }
1512
1513 // Find looks up the name/signature in the local methods array
1514 // and filters on the overpass, static and private flags
1515 // This returns the first one found
1516 // note that the local methods array can have up to one overpass, one static
1517 // and one instance (private or not) with the same name/signature
1518 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1519 const Symbol* name,
1520 const Symbol* signature,
1521 OverpassLookupMode overpass_mode,
1522 StaticLookupMode static_mode,
1523 PrivateLookupMode private_mode) {
1524 return InstanceKlass::find_method_impl(methods,
1525 name,
1526 signature,
1527 overpass_mode,
1528 static_mode,
1529 private_mode);
1530 }
1531
1532 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1533 const Symbol* name,
1534 const Symbol* signature) {
1535 return InstanceKlass::find_method_impl(methods,
1536 name,
1537 signature,
1538 find_overpass,
1539 find_static,
1540 find_private);
1541 }
1542
1543 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1544 const Symbol* name,
1545 const Symbol* signature,
1546 OverpassLookupMode overpass_mode,
1547 StaticLookupMode static_mode,
1548 PrivateLookupMode private_mode) {
1549 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1550 return hit >= 0 ? methods->at(hit): NULL;
1551 }
1552
1553 // true if method matches signature and conforms to skipping_X conditions.
1554 static bool method_matches(const Method* m,
1555 const Symbol* signature,
1556 bool skipping_overpass,
1557 bool skipping_static,
1558 bool skipping_private) {
1559 return ((m->signature() == signature) &&
1560 (!skipping_overpass || !m->is_overpass()) &&
1561 (!skipping_static || !m->is_static()) &&
1562 (!skipping_private || !m->is_private()));
1563 }
1564
1565 // Used directly for default_methods to find the index into the
1566 // default_vtable_indices, and indirectly by find_method
1567 // find_method_index looks in the local methods array to return the index
1568 // of the matching name/signature. If, overpass methods are being ignored,
1569 // the search continues to find a potential non-overpass match. This capability
1570 // is important during method resolution to prefer a static method, for example,
1571 // over an overpass method.
1572 // There is the possibility in any _method's array to have the same name/signature
1573 // for a static method, an overpass method and a local instance method
1574 // To correctly catch a given method, the search criteria may need
1575 // to explicitly skip the other two. For local instance methods, it
1576 // is often necessary to skip private methods
1577 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1578 const Symbol* name,
1579 const Symbol* signature,
1580 OverpassLookupMode overpass_mode,
1581 StaticLookupMode static_mode,
1582 PrivateLookupMode private_mode) {
1583 const bool skipping_overpass = (overpass_mode == skip_overpass);
1584 const bool skipping_static = (static_mode == skip_static);
1585 const bool skipping_private = (private_mode == skip_private);
1586 const int hit = binary_search(methods, name);
1587 if (hit != -1) {
1588 const Method* const m = methods->at(hit);
1589
1590 // Do linear search to find matching signature. First, quick check
1591 // for common case, ignoring overpasses if requested.
1592 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1593 return hit;
1594 }
1595
1596 // search downwards through overloaded methods
1597 int i;
1598 for (i = hit - 1; i >= 0; --i) {
1599 const Method* const m = methods->at(i);
1600 assert(m->is_method(), "must be method");
1601 if (m->name() != name) {
1602 break;
1603 }
1604 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1605 return i;
1606 }
1607 }
1608 // search upwards
1609 for (i = hit + 1; i < methods->length(); ++i) {
1610 const Method* const m = methods->at(i);
1611 assert(m->is_method(), "must be method");
1612 if (m->name() != name) {
1613 break;
1614 }
1615 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1616 return i;
1617 }
1618 }
1619 // not found
1620 #ifdef ASSERT
1621 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1622 linear_search(methods, name, signature);
1623 assert(-1 == index, "binary search should have found entry %d", index);
1624 #endif
1625 }
1626 return -1;
1627 }
1628
1629 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1630 return find_method_by_name(methods(), name, end);
1631 }
1632
1633 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1634 const Symbol* name,
1635 int* end_ptr) {
1636 assert(end_ptr != NULL, "just checking");
1637 int start = binary_search(methods, name);
1638 int end = start + 1;
1639 if (start != -1) {
1640 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1641 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1642 *end_ptr = end;
1643 return start;
1644 }
1645 return -1;
1646 }
1647
1648 // uncached_lookup_method searches both the local class methods array and all
1649 // superclasses methods arrays, skipping any overpass methods in superclasses.
1650 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1651 const Symbol* signature,
1652 OverpassLookupMode overpass_mode) const {
1653 OverpassLookupMode overpass_local_mode = overpass_mode;
1654 const Klass* klass = this;
1655 while (klass != NULL) {
1656 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1657 signature,
1658 overpass_local_mode,
1659 find_static,
1660 find_private);
1661 if (method != NULL) {
1662 return method;
1663 }
1664 klass = klass->super();
1665 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1666 }
1667 return NULL;
1668 }
1669
1670 #ifdef ASSERT
1671 // search through class hierarchy and return true if this class or
1672 // one of the superclasses was redefined
1673 bool InstanceKlass::has_redefined_this_or_super() const {
1674 const Klass* klass = this;
1675 while (klass != NULL) {
1676 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1677 return true;
1678 }
1679 klass = klass->super();
1680 }
1681 return false;
1682 }
1683 #endif
1684
1685 // lookup a method in the default methods list then in all transitive interfaces
1686 // Do NOT return private or static methods
1687 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1688 Symbol* signature) const {
1689 Method* m = NULL;
1690 if (default_methods() != NULL) {
1691 m = find_method(default_methods(), name, signature);
1692 }
1693 // Look up interfaces
1694 if (m == NULL) {
1695 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1696 }
1697 return m;
1698 }
1699
1700 // lookup a method in all the interfaces that this class implements
1701 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1702 // They should only be found in the initial InterfaceMethodRef
1703 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1704 Symbol* signature,
1705 DefaultsLookupMode defaults_mode) const {
1706 Array<Klass*>* all_ifs = transitive_interfaces();
1707 int num_ifs = all_ifs->length();
1708 InstanceKlass *ik = NULL;
1709 for (int i = 0; i < num_ifs; i++) {
1710 ik = InstanceKlass::cast(all_ifs->at(i));
1711 Method* m = ik->lookup_method(name, signature);
1712 if (m != NULL && m->is_public() && !m->is_static() &&
1713 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1714 return m;
1715 }
1716 }
1717 return NULL;
1718 }
1719
1720 /* jni_id_for_impl for jfieldIds only */
1721 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1722 MutexLocker ml(JfieldIdCreation_lock);
1723 // Retry lookup after we got the lock
1724 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1725 if (probe == NULL) {
1726 // Slow case, allocate new static field identifier
1727 probe = new JNIid(this, offset, jni_ids());
1728 set_jni_ids(probe);
1729 }
1730 return probe;
1731 }
1732
1733
1734 /* jni_id_for for jfieldIds only */
1735 JNIid* InstanceKlass::jni_id_for(int offset) {
1736 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1737 if (probe == NULL) {
1738 probe = jni_id_for_impl(offset);
1739 }
1740 return probe;
1741 }
1742
1743 u2 InstanceKlass::enclosing_method_data(int offset) const {
1744 const Array<jushort>* const inner_class_list = inner_classes();
1745 if (inner_class_list == NULL) {
1746 return 0;
1747 }
1748 const int length = inner_class_list->length();
1749 if (length % inner_class_next_offset == 0) {
1750 return 0;
1751 }
1752 const int index = length - enclosing_method_attribute_size;
1753 assert(offset < enclosing_method_attribute_size, "invalid offset");
1754 return inner_class_list->at(index + offset);
1755 }
1756
1757 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1758 u2 method_index) {
1759 Array<jushort>* inner_class_list = inner_classes();
1760 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1761 int length = inner_class_list->length();
1762 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1763 int index = length - enclosing_method_attribute_size;
1764 inner_class_list->at_put(
1765 index + enclosing_method_class_index_offset, class_index);
1766 inner_class_list->at_put(
1767 index + enclosing_method_method_index_offset, method_index);
1768 }
1769 }
1770
1771 // Lookup or create a jmethodID.
1772 // This code is called by the VMThread and JavaThreads so the
1773 // locking has to be done very carefully to avoid deadlocks
1774 // and/or other cache consistency problems.
1775 //
1776 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1777 size_t idnum = (size_t)method_h->method_idnum();
1778 jmethodID* jmeths = methods_jmethod_ids_acquire();
1779 size_t length = 0;
1780 jmethodID id = NULL;
1781
1782 // We use a double-check locking idiom here because this cache is
1783 // performance sensitive. In the normal system, this cache only
1784 // transitions from NULL to non-NULL which is safe because we use
1785 // release_set_methods_jmethod_ids() to advertise the new cache.
1786 // A partially constructed cache should never be seen by a racing
1787 // thread. We also use release_store() to save a new jmethodID
1788 // in the cache so a partially constructed jmethodID should never be
1789 // seen either. Cache reads of existing jmethodIDs proceed without a
1790 // lock, but cache writes of a new jmethodID requires uniqueness and
1791 // creation of the cache itself requires no leaks so a lock is
1792 // generally acquired in those two cases.
1793 //
1794 // If the RedefineClasses() API has been used, then this cache can
1795 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1796 // Cache creation requires no leaks and we require safety between all
1797 // cache accesses and freeing of the old cache so a lock is generally
1798 // acquired when the RedefineClasses() API has been used.
1799
1800 if (jmeths != NULL) {
1801 // the cache already exists
1802 if (!idnum_can_increment()) {
1803 // the cache can't grow so we can just get the current values
1804 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1805 } else {
1806 // cache can grow so we have to be more careful
1807 if (Threads::number_of_threads() == 0 ||
1808 SafepointSynchronize::is_at_safepoint()) {
1809 // we're single threaded or at a safepoint - no locking needed
1810 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1811 } else {
1812 MutexLocker ml(JmethodIdCreation_lock);
1813 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1814 }
1815 }
1816 }
1817 // implied else:
1818 // we need to allocate a cache so default length and id values are good
1819
1820 if (jmeths == NULL || // no cache yet
1821 length <= idnum || // cache is too short
1822 id == NULL) { // cache doesn't contain entry
1823
1824 // This function can be called by the VMThread so we have to do all
1825 // things that might block on a safepoint before grabbing the lock.
1826 // Otherwise, we can deadlock with the VMThread or have a cache
1827 // consistency issue. These vars keep track of what we might have
1828 // to free after the lock is dropped.
1829 jmethodID to_dealloc_id = NULL;
1830 jmethodID* to_dealloc_jmeths = NULL;
1831
1832 // may not allocate new_jmeths or use it if we allocate it
1833 jmethodID* new_jmeths = NULL;
1834 if (length <= idnum) {
1835 // allocate a new cache that might be used
1836 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1837 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1838 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1839 // cache size is stored in element[0], other elements offset by one
1840 new_jmeths[0] = (jmethodID)size;
1841 }
1842
1843 // allocate a new jmethodID that might be used
1844 jmethodID new_id = NULL;
1845 if (method_h->is_old() && !method_h->is_obsolete()) {
1846 // The method passed in is old (but not obsolete), we need to use the current version
1847 Method* current_method = method_with_idnum((int)idnum);
1848 assert(current_method != NULL, "old and but not obsolete, so should exist");
1849 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1850 } else {
1851 // It is the current version of the method or an obsolete method,
1852 // use the version passed in
1853 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1854 }
1855
1856 if (Threads::number_of_threads() == 0 ||
1857 SafepointSynchronize::is_at_safepoint()) {
1858 // we're single threaded or at a safepoint - no locking needed
1859 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1860 &to_dealloc_id, &to_dealloc_jmeths);
1861 } else {
1862 MutexLocker ml(JmethodIdCreation_lock);
1863 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1864 &to_dealloc_id, &to_dealloc_jmeths);
1865 }
1866
1867 // The lock has been dropped so we can free resources.
1868 // Free up either the old cache or the new cache if we allocated one.
1869 if (to_dealloc_jmeths != NULL) {
1870 FreeHeap(to_dealloc_jmeths);
1871 }
1872 // free up the new ID since it wasn't needed
1873 if (to_dealloc_id != NULL) {
1874 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1875 }
1876 }
1877 return id;
1878 }
1879
1880 // Figure out how many jmethodIDs haven't been allocated, and make
1881 // sure space for them is pre-allocated. This makes getting all
1882 // method ids much, much faster with classes with more than 8
1883 // methods, and has a *substantial* effect on performance with jvmti
1884 // code that loads all jmethodIDs for all classes.
1885 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1886 int new_jmeths = 0;
1887 int length = methods()->length();
1888 for (int index = start_offset; index < length; index++) {
1889 Method* m = methods()->at(index);
1890 jmethodID id = m->find_jmethod_id_or_null();
1891 if (id == NULL) {
1892 new_jmeths++;
1893 }
1894 }
1895 if (new_jmeths != 0) {
1896 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1897 }
1898 }
1899
1900 // Common code to fetch the jmethodID from the cache or update the
1901 // cache with the new jmethodID. This function should never do anything
1902 // that causes the caller to go to a safepoint or we can deadlock with
1903 // the VMThread or have cache consistency issues.
1904 //
1905 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1906 size_t idnum, jmethodID new_id,
1907 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1908 jmethodID** to_dealloc_jmeths_p) {
1909 assert(new_id != NULL, "sanity check");
1910 assert(to_dealloc_id_p != NULL, "sanity check");
1911 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1912 assert(Threads::number_of_threads() == 0 ||
1913 SafepointSynchronize::is_at_safepoint() ||
1914 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1915
1916 // reacquire the cache - we are locked, single threaded or at a safepoint
1917 jmethodID* jmeths = methods_jmethod_ids_acquire();
1918 jmethodID id = NULL;
1919 size_t length = 0;
1920
1921 if (jmeths == NULL || // no cache yet
1922 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1923 if (jmeths != NULL) {
1924 // copy any existing entries from the old cache
1925 for (size_t index = 0; index < length; index++) {
1926 new_jmeths[index+1] = jmeths[index+1];
1927 }
1928 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1929 }
1930 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1931 } else {
1932 // fetch jmethodID (if any) from the existing cache
1933 id = jmeths[idnum+1];
1934 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1935 }
1936 if (id == NULL) {
1937 // No matching jmethodID in the existing cache or we have a new
1938 // cache or we just grew the cache. This cache write is done here
1939 // by the first thread to win the foot race because a jmethodID
1940 // needs to be unique once it is generally available.
1941 id = new_id;
1942
1943 // The jmethodID cache can be read while unlocked so we have to
1944 // make sure the new jmethodID is complete before installing it
1945 // in the cache.
1946 OrderAccess::release_store(&jmeths[idnum+1], id);
1947 } else {
1948 *to_dealloc_id_p = new_id; // save new id for later delete
1949 }
1950 return id;
1951 }
1952
1953
1954 // Common code to get the jmethodID cache length and the jmethodID
1955 // value at index idnum if there is one.
1956 //
1957 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1958 size_t idnum, size_t *length_p, jmethodID* id_p) {
1959 assert(cache != NULL, "sanity check");
1960 assert(length_p != NULL, "sanity check");
1961 assert(id_p != NULL, "sanity check");
1962
1963 // cache size is stored in element[0], other elements offset by one
1964 *length_p = (size_t)cache[0];
1965 if (*length_p <= idnum) { // cache is too short
1966 *id_p = NULL;
1967 } else {
1968 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1969 }
1970 }
1971
1972
1973 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1974 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1975 size_t idnum = (size_t)method->method_idnum();
1976 jmethodID* jmeths = methods_jmethod_ids_acquire();
1977 size_t length; // length assigned as debugging crumb
1978 jmethodID id = NULL;
1979 if (jmeths != NULL && // If there is a cache
1980 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1981 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1982 }
1983 return id;
1984 }
1985
1986 inline DependencyContext InstanceKlass::dependencies() {
1987 DependencyContext dep_context(&_dep_context);
1988 return dep_context;
1989 }
1990
1991 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1992 return dependencies().mark_dependent_nmethods(changes);
1993 }
1994
1995 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1996 dependencies().add_dependent_nmethod(nm);
1997 }
1998
1999 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2000 dependencies().remove_dependent_nmethod(nm, delete_immediately);
2001 }
2002
2003 #ifndef PRODUCT
2004 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2005 dependencies().print_dependent_nmethods(verbose);
2006 }
2007
2008 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2009 return dependencies().is_dependent_nmethod(nm);
2010 }
2011 #endif //PRODUCT
2012
2013 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2014 clean_implementors_list(is_alive);
2015 clean_method_data(is_alive);
2016
2017 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2018 DependencyContext dep_context(&_dep_context);
2019 dep_context.expunge_stale_entries();
2020 }
2021
2022 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2023 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2024 if (is_interface()) {
2025 if (ClassUnloading) {
2026 Klass* impl = implementor();
2027 if (impl != NULL) {
2028 if (!impl->is_loader_alive(is_alive)) {
2029 // remove this guy
2030 Klass** klass = adr_implementor();
2031 assert(klass != NULL, "null klass");
2032 if (klass != NULL) {
2033 *klass = NULL;
2034 }
2035 }
2036 }
2037 }
2038 }
2039 }
2040
2041 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2042 for (int m = 0; m < methods()->length(); m++) {
2043 MethodData* mdo = methods()->at(m)->method_data();
2044 if (mdo != NULL) {
2045 mdo->clean_method_data(is_alive);
2046 }
2047 }
2048 }
2049
2050 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2051 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2052 ResourceMark rm;
2053 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2054 return false;
2055 }
2056
2057 Array<Klass*>* local_interfaces = this->local_interfaces();
2058 if (local_interfaces != NULL) {
2059 int length = local_interfaces->length();
2060 for (int i = 0; i < length; i++) {
2061 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2062 if (!intf->has_passed_fingerprint_check()) {
2063 ResourceMark rm;
2064 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2065 return false;
2066 }
2067 }
2068 }
2069
2070 return true;
2071 }
2072
2073 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) {
2074 #if INCLUDE_AOT
2075 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2076 if (CalculateClassFingerprint) {
2077 // (1) We are running AOT to generate a shared library.
2078 return true;
2079 }
2080 if (DumpSharedSpaces) {
2081 // (2) We are running -Xshare:dump to create a shared archive
2082 return true;
2083 }
2084 if (UseAOT && is_anonymous) {
2085 // (3) We are using AOT code from a shared library and see an anonymous class
2086 return true;
2087 }
2088 #endif
2089
2090 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2091 // but do not store the 64-bit fingerprint to save space.
2092 return false;
2093 }
2094
2095 bool InstanceKlass::has_stored_fingerprint() const {
2096 #if INCLUDE_AOT
2097 return should_store_fingerprint() || is_shared();
2098 #else
2099 return false;
2100 #endif
2101 }
2102
2103 uint64_t InstanceKlass::get_stored_fingerprint() const {
2104 address adr = adr_fingerprint();
2105 if (adr != NULL) {
2106 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2107 }
2108 return 0;
2109 }
2110
2111 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2112 address adr = adr_fingerprint();
2113 if (adr != NULL) {
2114 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2115
2116 ResourceMark rm;
2117 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2118 }
2119 }
2120
2121 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2122 Klass::metaspace_pointers_do(it);
2123
2124 if (log_is_enabled(Trace, cds)) {
2125 ResourceMark rm;
2126 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2127 }
2128
2129 it->push(&_annotations);
2130 it->push((Klass**)&_array_klasses);
2131 it->push(&_constants);
2132 it->push(&_inner_classes);
2133 it->push(&_array_name);
2134 #if INCLUDE_JVMTI
2135 it->push(&_previous_versions);
2136 #endif
2137 it->push(&_methods);
2138 it->push(&_default_methods);
2139 it->push(&_local_interfaces);
2140 it->push(&_transitive_interfaces);
2141 it->push(&_method_ordering);
2142 it->push(&_default_vtable_indices);
2143 it->push(&_fields);
2144
2145 if (itable_length() > 0) {
2146 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2147 int method_table_offset_in_words = ioe->offset()/wordSize;
2148 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2149 / itableOffsetEntry::size();
2150
2151 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2152 if (ioe->interface_klass() != NULL) {
2153 it->push(ioe->interface_klass_addr());
2154 itableMethodEntry* ime = ioe->first_method_entry(this);
2155 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2156 for (int index = 0; index < n; index ++) {
2157 it->push(ime[index].method_addr());
2158 }
2159 }
2160 }
2161 }
2162 }
2163
2164 void InstanceKlass::remove_unshareable_info() {
2165 Klass::remove_unshareable_info();
2166
2167 if (is_in_error_state()) {
2168 // Classes are attempted to link during dumping and may fail,
2169 // but these classes are still in the dictionary and class list in CLD.
2170 // Check in_error state first because in_error is > linked state, so
2171 // is_linked() is true.
2172 // If there's a linking error, there is nothing else to remove.
2173 return;
2174 }
2175
2176 // Unlink the class
2177 if (is_linked()) {
2178 unlink_class();
2179 }
2180 init_implementor();
2181
2182 constants()->remove_unshareable_info();
2183
2184 for (int i = 0; i < methods()->length(); i++) {
2185 Method* m = methods()->at(i);
2186 m->remove_unshareable_info();
2187 }
2188
2189 // do array classes also.
2190 if (array_klasses() != NULL) {
2191 array_klasses()->remove_unshareable_info();
2192 }
2193
2194 // These are not allocated from metaspace, but they should should all be empty
2195 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2196 guarantee(_source_debug_extension == NULL, "must be");
2197 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2198 guarantee(_osr_nmethods_head == NULL, "must be");
2199
2200 #if INCLUDE_JVMTI
2201 guarantee(_breakpoints == NULL, "must be");
2202 guarantee(_previous_versions == NULL, "must be");
2203 #endif
2204
2205 _init_thread = NULL;
2206 _methods_jmethod_ids = NULL;
2207 _jni_ids = NULL;
2208 _oop_map_cache = NULL;
2209 }
2210
2211 void InstanceKlass::remove_java_mirror() {
2212 Klass::remove_java_mirror();
2213
2214 // do array classes also.
2215 if (array_klasses() != NULL) {
2216 array_klasses()->remove_java_mirror();
2217 }
2218 }
2219
2220 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2221 set_package(loader_data, CHECK);
2222 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2223
2224 Array<Method*>* methods = this->methods();
2225 int num_methods = methods->length();
2226 for (int index2 = 0; index2 < num_methods; ++index2) {
2227 methodHandle m(THREAD, methods->at(index2));
2228 m->restore_unshareable_info(CHECK);
2229 }
2230 if (JvmtiExport::has_redefined_a_class()) {
2231 // Reinitialize vtable because RedefineClasses may have changed some
2232 // entries in this vtable for super classes so the CDS vtable might
2233 // point to old or obsolete entries. RedefineClasses doesn't fix up
2234 // vtables in the shared system dictionary, only the main one.
2235 // It also redefines the itable too so fix that too.
2236 ResourceMark rm(THREAD);
2237 vtable().initialize_vtable(false, CHECK);
2238 itable().initialize_itable(false, CHECK);
2239 }
2240
2241 // restore constant pool resolved references
2242 constants()->restore_unshareable_info(CHECK);
2243
2244 if (array_klasses() != NULL) {
2245 // Array classes have null protection domain.
2246 // --> see ArrayKlass::complete_create_array_klass()
2247 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2248 }
2249 }
2250
2251 // returns true IFF is_in_error_state() has been changed as a result of this call.
2252 bool InstanceKlass::check_sharing_error_state() {
2253 assert(DumpSharedSpaces, "should only be called during dumping");
2254 bool old_state = is_in_error_state();
2255
2256 if (!is_in_error_state()) {
2257 bool bad = false;
2258 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2259 if (sup->is_in_error_state()) {
2260 bad = true;
2261 break;
2262 }
2263 }
2264 if (!bad) {
2265 Array<Klass*>* interfaces = transitive_interfaces();
2266 for (int i = 0; i < interfaces->length(); i++) {
2267 Klass* iface = interfaces->at(i);
2268 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2269 bad = true;
2270 break;
2271 }
2272 }
2273 }
2274
2275 if (bad) {
2276 set_in_error_state();
2277 }
2278 }
2279
2280 return (old_state != is_in_error_state());
2281 }
2282
2283 #if INCLUDE_JVMTI
2284 static void clear_all_breakpoints(Method* m) {
2285 m->clear_all_breakpoints();
2286 }
2287 #endif
2288
2289 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2290 // notify the debugger
2291 if (JvmtiExport::should_post_class_unload()) {
2292 JvmtiExport::post_class_unload(ik);
2293 }
2294
2295 // notify ClassLoadingService of class unload
2296 ClassLoadingService::notify_class_unloaded(ik);
2297 }
2298
2299 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2300 // Clean up C heap
2301 ik->release_C_heap_structures();
2302 ik->constants()->release_C_heap_structures();
2303 }
2304
2305 void InstanceKlass::release_C_heap_structures() {
2306 // Can't release the constant pool here because the constant pool can be
2307 // deallocated separately from the InstanceKlass for default methods and
2308 // redefine classes.
2309
2310 // Deallocate oop map cache
2311 if (_oop_map_cache != NULL) {
2312 delete _oop_map_cache;
2313 _oop_map_cache = NULL;
2314 }
2315
2316 // Deallocate JNI identifiers for jfieldIDs
2317 JNIid::deallocate(jni_ids());
2318 set_jni_ids(NULL);
2319
2320 jmethodID* jmeths = methods_jmethod_ids_acquire();
2321 if (jmeths != (jmethodID*)NULL) {
2322 release_set_methods_jmethod_ids(NULL);
2323 FreeHeap(jmeths);
2324 }
2325
2326 // Release dependencies.
2327 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2328 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2329 // context can contain live dependencies, since there's a race between nmethod &
2330 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2331 // dependencies aren't removed from the context associated with the class (see
2332 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2333 // live dependencies pointing to unloaded nmethods and causes a crash in
2334 // DC::remove_all_dependents() when it touches unloaded nmethod.
2335 dependencies().wipe();
2336
2337 #if INCLUDE_JVMTI
2338 // Deallocate breakpoint records
2339 if (breakpoints() != 0x0) {
2340 methods_do(clear_all_breakpoints);
2341 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2342 }
2343
2344 // deallocate the cached class file
2345 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2346 os::free(_cached_class_file);
2347 _cached_class_file = NULL;
2348 }
2349 #endif
2350
2351 // Decrement symbol reference counts associated with the unloaded class.
2352 if (_name != NULL) _name->decrement_refcount();
2353 // unreference array name derived from this class name (arrays of an unloaded
2354 // class can't be referenced anymore).
2355 if (_array_name != NULL) _array_name->decrement_refcount();
2356 if (_value_types != NULL) {
2357 for (int i = 0; i < _value_types->length(); i++) {
2358 Symbol* s = _value_types->at(i)._class_name;
2359 if (s != NULL) {
2360 s->decrement_refcount();
2361 }
2362 }
2363 }
2364 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2365 }
2366
2367 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2368 if (array == NULL) {
2369 _source_debug_extension = NULL;
2370 } else {
2371 // Adding one to the attribute length in order to store a null terminator
2372 // character could cause an overflow because the attribute length is
2373 // already coded with an u4 in the classfile, but in practice, it's
2374 // unlikely to happen.
2375 assert((length+1) > length, "Overflow checking");
2376 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2377 for (int i = 0; i < length; i++) {
2378 sde[i] = array[i];
2379 }
2380 sde[length] = '\0';
2381 _source_debug_extension = sde;
2382 }
2383 }
2384
2385 address InstanceKlass::static_field_addr(int offset) {
2386 assert(offset >= InstanceMirrorKlass::offset_of_static_fields(), "has already been adjusted");
2387 return (address)(offset + cast_from_oop<intptr_t>(java_mirror()));
2388 }
2389
2390
2391 const char* InstanceKlass::signature_name() const {
2392 int hash_len = 0;
2393 char hash_buf[40];
2394
2395 // If this is an anonymous class, append a hash to make the name unique
2396 if (is_anonymous()) {
2397 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2398 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2399 hash_len = (int)strlen(hash_buf);
2400 }
2401
2402 // Get the internal name as a c string
2403 const char* src = (const char*) (name()->as_C_string());
2404 const int src_length = (int)strlen(src);
2405
2406 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2407
2408 // Add L as type indicator
2409 int dest_index = 0;
2410 dest[dest_index++] = 'L';
2411
2412 // Add the actual class name
2413 for (int src_index = 0; src_index < src_length; ) {
2414 dest[dest_index++] = src[src_index++];
2415 }
2416
2417 // If we have a hash, append it
2418 for (int hash_index = 0; hash_index < hash_len; ) {
2419 dest[dest_index++] = hash_buf[hash_index++];
2420 }
2421
2422 // Add the semicolon and the NULL
2423 dest[dest_index++] = ';';
2424 dest[dest_index] = '\0';
2425 return dest;
2426 }
2427
2428 // Used to obtain the package name from a fully qualified class name.
2429 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2430 if (name == NULL) {
2431 return NULL;
2432 } else {
2433 if (name->utf8_length() <= 0) {
2434 return NULL;
2435 }
2436 ResourceMark rm;
2437 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2438 if (package_name == NULL) {
2439 return NULL;
2440 }
2441 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2442 return pkg_name;
2443 }
2444 }
2445
2446 ModuleEntry* InstanceKlass::module() const {
2447 if (!in_unnamed_package()) {
2448 return _package_entry->module();
2449 }
2450 const Klass* host = host_klass();
2451 if (host == NULL) {
2452 return class_loader_data()->unnamed_module();
2453 }
2454 return host->class_loader_data()->unnamed_module();
2455 }
2456
2457 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2458
2459 // ensure java/ packages only loaded by boot or platform builtin loaders
2460 Handle class_loader(THREAD, loader_data->class_loader());
2461 check_prohibited_package(name(), class_loader, CHECK);
2462
2463 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2464
2465 if (pkg_name != NULL && loader_data != NULL) {
2466
2467 // Find in class loader's package entry table.
2468 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2469
2470 // If the package name is not found in the loader's package
2471 // entry table, it is an indication that the package has not
2472 // been defined. Consider it defined within the unnamed module.
2473 if (_package_entry == NULL) {
2474 ResourceMark rm;
2475
2476 if (!ModuleEntryTable::javabase_defined()) {
2477 // Before java.base is defined during bootstrapping, define all packages in
2478 // the java.base module. If a non-java.base package is erroneously placed
2479 // in the java.base module it will be caught later when java.base
2480 // is defined by ModuleEntryTable::verify_javabase_packages check.
2481 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2482 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2483 } else {
2484 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2485 _package_entry = loader_data->packages()->lookup(pkg_name,
2486 loader_data->unnamed_module());
2487 }
2488
2489 // A package should have been successfully created
2490 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2491 name()->as_C_string(), loader_data->loader_name());
2492 }
2493
2494 if (log_is_enabled(Debug, module)) {
2495 ResourceMark rm;
2496 ModuleEntry* m = _package_entry->module();
2497 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2498 external_name(),
2499 pkg_name->as_C_string(),
2500 loader_data->loader_name(),
2501 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2502 }
2503 } else {
2504 ResourceMark rm;
2505 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2506 external_name(),
2507 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2508 UNNAMED_MODULE);
2509 }
2510 }
2511
2512
2513 // different versions of is_same_class_package
2514
2515 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2516 oop classloader1 = this->class_loader();
2517 PackageEntry* classpkg1 = this->package();
2518 if (class2->is_objArray_klass()) {
2519 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2520 }
2521
2522 oop classloader2;
2523 PackageEntry* classpkg2;
2524 if (class2->is_instance_klass()) {
2525 classloader2 = class2->class_loader();
2526 classpkg2 = class2->package();
2527 } else {
2528 assert(class2->is_typeArray_klass(), "should be type array");
2529 classloader2 = NULL;
2530 classpkg2 = NULL;
2531 }
2532
2533 // Same package is determined by comparing class loader
2534 // and package entries. Both must be the same. This rule
2535 // applies even to classes that are defined in the unnamed
2536 // package, they still must have the same class loader.
2537 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2538 return true;
2539 }
2540
2541 return false;
2542 }
2543
2544 // return true if this class and other_class are in the same package. Classloader
2545 // and classname information is enough to determine a class's package
2546 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2547 const Symbol* other_class_name) const {
2548 if (class_loader() != other_class_loader) {
2549 return false;
2550 }
2551 if (name()->fast_compare(other_class_name) == 0) {
2552 return true;
2553 }
2554
2555 {
2556 ResourceMark rm;
2557
2558 bool bad_class_name = false;
2559 const char* other_pkg =
2560 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2561 if (bad_class_name) {
2562 return false;
2563 }
2564 // Check that package_from_name() returns NULL, not "", if there is no package.
2565 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2566
2567 const Symbol* const this_package_name =
2568 this->package() != NULL ? this->package()->name() : NULL;
2569
2570 if (this_package_name == NULL || other_pkg == NULL) {
2571 // One of the two doesn't have a package. Only return true if the other
2572 // one also doesn't have a package.
2573 return (const char*)this_package_name == other_pkg;
2574 }
2575
2576 // Check if package is identical
2577 return this_package_name->equals(other_pkg);
2578 }
2579 }
2580
2581 // Returns true iff super_method can be overridden by a method in targetclassname
2582 // See JLS 3rd edition 8.4.6.1
2583 // Assumes name-signature match
2584 // "this" is InstanceKlass of super_method which must exist
2585 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2586 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2587 // Private methods can not be overridden
2588 if (super_method->is_private()) {
2589 return false;
2590 }
2591 // If super method is accessible, then override
2592 if ((super_method->is_protected()) ||
2593 (super_method->is_public())) {
2594 return true;
2595 }
2596 // Package-private methods are not inherited outside of package
2597 assert(super_method->is_package_private(), "must be package private");
2598 return(is_same_class_package(targetclassloader(), targetclassname));
2599 }
2600
2601 // Only boot and platform class loaders can define classes in "java/" packages.
2602 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2603 Handle class_loader,
2604 TRAPS) {
2605 if (!class_loader.is_null() &&
2606 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2607 class_name != NULL) {
2608 ResourceMark rm(THREAD);
2609 char* name = class_name->as_C_string();
2610 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2611 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2612 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2613 name = pkg_name->as_C_string();
2614 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2615 StringUtils::replace_no_expand(name, "/", ".");
2616 const char* msg_text1 = "Class loader (instance of): ";
2617 const char* msg_text2 = " tried to load prohibited package name: ";
2618 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2619 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2620 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2621 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2622 }
2623 }
2624 return;
2625 }
2626
2627 // tell if two classes have the same enclosing class (at package level)
2628 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2629 if (class2 == this) return true;
2630 if (!class2->is_instance_klass()) return false;
2631
2632 // must be in same package before we try anything else
2633 if (!is_same_class_package(class2))
2634 return false;
2635
2636 // As long as there is an outer_this.getEnclosingClass,
2637 // shift the search outward.
2638 const InstanceKlass* outer_this = this;
2639 for (;;) {
2640 // As we walk along, look for equalities between outer_this and class2.
2641 // Eventually, the walks will terminate as outer_this stops
2642 // at the top-level class around the original class.
2643 bool ignore_inner_is_member;
2644 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2645 CHECK_false);
2646 if (next == NULL) break;
2647 if (next == class2) return true;
2648 outer_this = InstanceKlass::cast(next);
2649 }
2650
2651 // Now do the same for class2.
2652 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2653 for (;;) {
2654 bool ignore_inner_is_member;
2655 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2656 CHECK_false);
2657 if (next == NULL) break;
2658 // Might as well check the new outer against all available values.
2659 if (next == this) return true;
2660 if (next == outer_this) return true;
2661 outer2 = InstanceKlass::cast(next);
2662 }
2663
2664 // If by this point we have not found an equality between the
2665 // two classes, we know they are in separate package members.
2666 return false;
2667 }
2668
2669 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2670 constantPoolHandle i_cp(THREAD, constants());
2671 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2672 int ioff = iter.inner_class_info_index();
2673 if (ioff != 0) {
2674 // Check to see if the name matches the class we're looking for
2675 // before attempting to find the class.
2676 if (i_cp->klass_name_at_matches(this, ioff)) {
2677 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2678 if (this == inner_klass) {
2679 *ooff = iter.outer_class_info_index();
2680 *noff = iter.inner_name_index();
2681 return true;
2682 }
2683 }
2684 }
2685 }
2686 return false;
2687 }
2688
2689 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2690 InstanceKlass* outer_klass = NULL;
2691 *inner_is_member = false;
2692 int ooff = 0, noff = 0;
2693 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2694 if (has_inner_classes_attr) {
2695 constantPoolHandle i_cp(THREAD, constants());
2696 if (ooff != 0) {
2697 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2698 outer_klass = InstanceKlass::cast(ok);
2699 *inner_is_member = true;
2700 }
2701 if (NULL == outer_klass) {
2702 // It may be anonymous; try for that.
2703 int encl_method_class_idx = enclosing_method_class_index();
2704 if (encl_method_class_idx != 0) {
2705 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2706 outer_klass = InstanceKlass::cast(ok);
2707 *inner_is_member = false;
2708 }
2709 }
2710 }
2711
2712 // If no inner class attribute found for this class.
2713 if (NULL == outer_klass) return NULL;
2714
2715 // Throws an exception if outer klass has not declared k as an inner klass
2716 // We need evidence that each klass knows about the other, or else
2717 // the system could allow a spoof of an inner class to gain access rights.
2718 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2719 return outer_klass;
2720 }
2721
2722 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2723 jint access = access_flags().as_int();
2724
2725 // But check if it happens to be member class.
2726 InnerClassesIterator iter(this);
2727 for (; !iter.done(); iter.next()) {
2728 int ioff = iter.inner_class_info_index();
2729 // Inner class attribute can be zero, skip it.
2730 // Strange but true: JVM spec. allows null inner class refs.
2731 if (ioff == 0) continue;
2732
2733 // only look at classes that are already loaded
2734 // since we are looking for the flags for our self.
2735 Symbol* inner_name = constants()->klass_name_at(ioff);
2736 if (name() == inner_name) {
2737 // This is really a member class.
2738 access = iter.inner_access_flags();
2739 break;
2740 }
2741 }
2742 // Remember to strip ACC_SUPER bit
2743 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2744 }
2745
2746 jint InstanceKlass::jvmti_class_status() const {
2747 jint result = 0;
2748
2749 if (is_linked()) {
2750 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2751 }
2752
2753 if (is_initialized()) {
2754 assert(is_linked(), "Class status is not consistent");
2755 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2756 }
2757 if (is_in_error_state()) {
2758 result |= JVMTI_CLASS_STATUS_ERROR;
2759 }
2760 return result;
2761 }
2762
2763 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2764 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2765 int method_table_offset_in_words = ioe->offset()/wordSize;
2766 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2767 / itableOffsetEntry::size();
2768
2769 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2770 // If the interface isn't implemented by the receiver class,
2771 // the VM should throw IncompatibleClassChangeError.
2772 if (cnt >= nof_interfaces) {
2773 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2774 }
2775
2776 Klass* ik = ioe->interface_klass();
2777 if (ik == holder) break;
2778 }
2779
2780 itableMethodEntry* ime = ioe->first_method_entry(this);
2781 Method* m = ime[index].method();
2782 if (m == NULL) {
2783 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2784 }
2785 return m;
2786 }
2787
2788
2789 #if INCLUDE_JVMTI
2790 // update default_methods for redefineclasses for methods that are
2791 // not yet in the vtable due to concurrent subclass define and superinterface
2792 // redefinition
2793 // Note: those in the vtable, should have been updated via adjust_method_entries
2794 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2795 // search the default_methods for uses of either obsolete or EMCP methods
2796 if (default_methods() != NULL) {
2797 for (int index = 0; index < default_methods()->length(); index ++) {
2798 Method* old_method = default_methods()->at(index);
2799 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2800 continue; // skip uninteresting entries
2801 }
2802 assert(!old_method->is_deleted(), "default methods may not be deleted");
2803
2804 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2805
2806 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2807 assert(old_method != new_method, "sanity check");
2808
2809 default_methods()->at_put(index, new_method);
2810 if (log_is_enabled(Info, redefine, class, update)) {
2811 ResourceMark rm;
2812 if (!(*trace_name_printed)) {
2813 log_info(redefine, class, update)
2814 ("adjust: klassname=%s default methods from name=%s",
2815 external_name(), old_method->method_holder()->external_name());
2816 *trace_name_printed = true;
2817 }
2818 log_debug(redefine, class, update, vtables)
2819 ("default method update: %s(%s) ",
2820 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2821 }
2822 }
2823 }
2824 }
2825 #endif // INCLUDE_JVMTI
2826
2827 // On-stack replacement stuff
2828 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2829 // only one compilation can be active
2830 {
2831 // This is a short non-blocking critical region, so the no safepoint check is ok.
2832 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2833 assert(n->is_osr_method(), "wrong kind of nmethod");
2834 n->set_osr_link(osr_nmethods_head());
2835 set_osr_nmethods_head(n);
2836 // Raise the highest osr level if necessary
2837 if (TieredCompilation) {
2838 Method* m = n->method();
2839 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2840 }
2841 }
2842
2843 // Get rid of the osr methods for the same bci that have lower levels.
2844 if (TieredCompilation) {
2845 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2846 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2847 if (inv != NULL && inv->is_in_use()) {
2848 inv->make_not_entrant();
2849 }
2850 }
2851 }
2852 }
2853
2854 // Remove osr nmethod from the list. Return true if found and removed.
2855 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2856 // This is a short non-blocking critical region, so the no safepoint check is ok.
2857 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2858 assert(n->is_osr_method(), "wrong kind of nmethod");
2859 nmethod* last = NULL;
2860 nmethod* cur = osr_nmethods_head();
2861 int max_level = CompLevel_none; // Find the max comp level excluding n
2862 Method* m = n->method();
2863 // Search for match
2864 bool found = false;
2865 while(cur != NULL && cur != n) {
2866 if (TieredCompilation && m == cur->method()) {
2867 // Find max level before n
2868 max_level = MAX2(max_level, cur->comp_level());
2869 }
2870 last = cur;
2871 cur = cur->osr_link();
2872 }
2873 nmethod* next = NULL;
2874 if (cur == n) {
2875 found = true;
2876 next = cur->osr_link();
2877 if (last == NULL) {
2878 // Remove first element
2879 set_osr_nmethods_head(next);
2880 } else {
2881 last->set_osr_link(next);
2882 }
2883 }
2884 n->set_osr_link(NULL);
2885 if (TieredCompilation) {
2886 cur = next;
2887 while (cur != NULL) {
2888 // Find max level after n
2889 if (m == cur->method()) {
2890 max_level = MAX2(max_level, cur->comp_level());
2891 }
2892 cur = cur->osr_link();
2893 }
2894 m->set_highest_osr_comp_level(max_level);
2895 }
2896 return found;
2897 }
2898
2899 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2900 // This is a short non-blocking critical region, so the no safepoint check is ok.
2901 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2902 nmethod* osr = osr_nmethods_head();
2903 int found = 0;
2904 while (osr != NULL) {
2905 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2906 if (osr->method() == m) {
2907 osr->mark_for_deoptimization();
2908 found++;
2909 }
2910 osr = osr->osr_link();
2911 }
2912 return found;
2913 }
2914
2915 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2916 // This is a short non-blocking critical region, so the no safepoint check is ok.
2917 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2918 nmethod* osr = osr_nmethods_head();
2919 nmethod* best = NULL;
2920 while (osr != NULL) {
2921 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2922 // There can be a time when a c1 osr method exists but we are waiting
2923 // for a c2 version. When c2 completes its osr nmethod we will trash
2924 // the c1 version and only be able to find the c2 version. However
2925 // while we overflow in the c1 code at back branches we don't want to
2926 // try and switch to the same code as we are already running
2927
2928 if (osr->method() == m &&
2929 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2930 if (match_level) {
2931 if (osr->comp_level() == comp_level) {
2932 // Found a match - return it.
2933 return osr;
2934 }
2935 } else {
2936 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2937 if (osr->comp_level() == CompLevel_highest_tier) {
2938 // Found the best possible - return it.
2939 return osr;
2940 }
2941 best = osr;
2942 }
2943 }
2944 }
2945 osr = osr->osr_link();
2946 }
2947 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2948 return best;
2949 }
2950 return NULL;
2951 }
2952
2953 // -----------------------------------------------------------------------------------------------------
2954 // Printing
2955
2956 #ifndef PRODUCT
2957
2958 #define BULLET " - "
2959
2960 static const char* state_names[] = {
2961 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2962 };
2963
2964 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
2965 ResourceMark rm;
2966 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
2967 for (int i = 0; i < len; i++) forward_refs[i] = 0;
2968 for (int i = 0; i < len; i++) {
2969 intptr_t e = start[i];
2970 st->print("%d : " INTPTR_FORMAT, i, e);
2971 if (forward_refs[i] != 0) {
2972 int from = forward_refs[i];
2973 int off = (int) start[from];
2974 st->print(" (offset %d <= [%d])", off, from);
2975 }
2976 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2977 st->print(" ");
2978 ((Metadata*)e)->print_value_on(st);
2979 } else if (self != NULL && e > 0 && e < 0x10000) {
2980 address location = self + e;
2981 int index = (int)((intptr_t*)location - start);
2982 st->print(" (offset %d => [%d])", (int)e, index);
2983 if (index >= 0 && index < len)
2984 forward_refs[index] = i;
2985 }
2986 st->cr();
2987 }
2988 }
2989
2990 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2991 return print_vtable(NULL, reinterpret_cast<intptr_t*>(start), len, st);
2992 }
2993
2994 template<typename T>
2995 static void print_array_on(outputStream* st, Array<T>* array) {
2996 if (array == NULL) { st->print_cr("NULL"); return; }
2997 array->print_value_on(st); st->cr();
2998 if (Verbose || WizardMode) {
2999 for (int i = 0; i < array->length(); i++) {
3000 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
3001 }
3002 }
3003 }
3004
3005 static void print_array_on(outputStream* st, Array<int>* array) {
3006 if (array == NULL) { st->print_cr("NULL"); return; }
3007 array->print_value_on(st); st->cr();
3008 if (Verbose || WizardMode) {
3009 for (int i = 0; i < array->length(); i++) {
3010 st->print("%d : %d", i, array->at(i)); st->cr();
3011 }
3012 }
3013 }
3014
3015 void InstanceKlass::print_on(outputStream* st) const {
3016 assert(is_klass(), "must be klass");
3017 Klass::print_on(st);
3018
3019 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3020 st->print(BULLET"klass size: %d", size()); st->cr();
3021 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3022 st->print(BULLET"misc flags: 0x%x", _misc_flags); st->cr();
3023 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3024 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3025 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3026 st->print(BULLET"sub: ");
3027 Klass* sub = subklass();
3028 int n;
3029 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3030 if (n < MaxSubklassPrintSize) {
3031 sub->print_value_on(st);
3032 st->print(" ");
3033 }
3034 }
3035 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3036 st->cr();
3037
3038 if (is_interface()) {
3039 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3040 if (nof_implementors() == 1) {
3041 st->print_cr(BULLET"implementor: ");
3042 st->print(" ");
3043 implementor()->print_value_on(st);
3044 st->cr();
3045 }
3046 }
3047
3048 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3049 st->print(BULLET"methods: "); print_array_on(st, methods());
3050 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3051 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3052 if (default_vtable_indices() != NULL) {
3053 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3054 }
3055 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3056 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3057 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3058 if (class_loader_data() != NULL) {
3059 st->print(BULLET"class loader data: ");
3060 class_loader_data()->print_value_on(st);
3061 st->cr();
3062 }
3063 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3064 if (source_file_name() != NULL) {
3065 st->print(BULLET"source file: ");
3066 source_file_name()->print_value_on(st);
3067 st->cr();
3068 }
3069 if (source_debug_extension() != NULL) {
3070 st->print(BULLET"source debug extension: ");
3071 st->print("%s", source_debug_extension());
3072 st->cr();
3073 }
3074 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3075 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3076 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3077 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3078 {
3079 bool have_pv = false;
3080 // previous versions are linked together through the InstanceKlass
3081 for (InstanceKlass* pv_node = previous_versions();
3082 pv_node != NULL;
3083 pv_node = pv_node->previous_versions()) {
3084 if (!have_pv)
3085 st->print(BULLET"previous version: ");
3086 have_pv = true;
3087 pv_node->constants()->print_value_on(st);
3088 }
3089 if (have_pv) st->cr();
3090 }
3091
3092 if (generic_signature() != NULL) {
3093 st->print(BULLET"generic signature: ");
3094 generic_signature()->print_value_on(st);
3095 st->cr();
3096 }
3097 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3098 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3099 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3100 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3101 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3102 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(NULL, start_of_itable(), itable_length(), st);
3103 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3104 FieldPrinter print_static_field(st);
3105 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3106 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3107 FieldPrinter print_nonstatic_field(st);
3108 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3109 ik->do_nonstatic_fields(&print_nonstatic_field);
3110
3111 st->print(BULLET"non-static oop maps: ");
3112 OopMapBlock* map = start_of_nonstatic_oop_maps();
3113 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3114 while (map < end_map) {
3115 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3116 map++;
3117 }
3118 st->cr();
3119 }
3120
3121 #endif //PRODUCT
3122
3123 void InstanceKlass::print_value_on(outputStream* st) const {
3124 assert(is_klass(), "must be klass");
3125 if (Verbose || WizardMode) access_flags().print_on(st);
3126 name()->print_value_on(st);
3127 }
3128
3129 #ifndef PRODUCT
3130
3131 void FieldPrinter::do_field(fieldDescriptor* fd) {
3132 _st->print(BULLET);
3133 if (_obj == NULL) {
3134 fd->print_on(_st);
3135 _st->cr();
3136 } else {
3137 fd->print_on_for(_st, _obj);
3138 _st->cr();
3139 }
3140 }
3141
3142
3143 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3144 Klass::oop_print_on(obj, st);
3145
3146 if (this == SystemDictionary::String_klass()) {
3147 typeArrayOop value = java_lang_String::value(obj);
3148 juint length = java_lang_String::length(obj);
3149 if (value != NULL &&
3150 value->is_typeArray() &&
3151 length <= (juint) value->length()) {
3152 st->print(BULLET"string: ");
3153 java_lang_String::print(obj, st);
3154 st->cr();
3155 if (!WizardMode) return; // that is enough
3156 }
3157 }
3158
3159 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3160 FieldPrinter print_field(st, obj);
3161 do_nonstatic_fields(&print_field);
3162
3163 if (this == SystemDictionary::Class_klass()) {
3164 st->print(BULLET"signature: ");
3165 java_lang_Class::print_signature(obj, st);
3166 st->cr();
3167 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3168 st->print(BULLET"fake entry for mirror: ");
3169 mirrored_klass->print_value_on_maybe_null(st);
3170 st->cr();
3171 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3172 st->print(BULLET"fake entry for array: ");
3173 array_klass->print_value_on_maybe_null(st);
3174 st->cr();
3175 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3176 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3177 Klass* real_klass = java_lang_Class::as_Klass(obj);
3178 if (real_klass != NULL && real_klass->is_instance_klass()) {
3179 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3180 }
3181 } else if (this == SystemDictionary::MethodType_klass()) {
3182 st->print(BULLET"signature: ");
3183 java_lang_invoke_MethodType::print_signature(obj, st);
3184 st->cr();
3185 }
3186 }
3187
3188 #endif //PRODUCT
3189
3190 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3191 st->print("a ");
3192 name()->print_value_on(st);
3193 obj->print_address_on(st);
3194 if (this == SystemDictionary::String_klass()
3195 && java_lang_String::value(obj) != NULL) {
3196 ResourceMark rm;
3197 int len = java_lang_String::length(obj);
3198 int plen = (len < 24 ? len : 12);
3199 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3200 st->print(" = \"%s\"", str);
3201 if (len > plen)
3202 st->print("...[%d]", len);
3203 } else if (this == SystemDictionary::Class_klass()) {
3204 Klass* k = java_lang_Class::as_Klass(obj);
3205 st->print(" = ");
3206 if (k != NULL) {
3207 k->print_value_on(st);
3208 } else {
3209 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3210 st->print("%s", tname ? tname : "type?");
3211 }
3212 } else if (this == SystemDictionary::MethodType_klass()) {
3213 st->print(" = ");
3214 java_lang_invoke_MethodType::print_signature(obj, st);
3215 } else if (java_lang_boxing_object::is_instance(obj)) {
3216 st->print(" = ");
3217 java_lang_boxing_object::print(obj, st);
3218 } else if (this == SystemDictionary::LambdaForm_klass()) {
3219 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3220 if (vmentry != NULL) {
3221 st->print(" => ");
3222 vmentry->print_value_on(st);
3223 }
3224 } else if (this == SystemDictionary::MemberName_klass()) {
3225 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3226 if (vmtarget != NULL) {
3227 st->print(" = ");
3228 vmtarget->print_value_on(st);
3229 } else {
3230 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3231 st->print(".");
3232 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3233 }
3234 }
3235 }
3236
3237 const char* InstanceKlass::internal_name() const {
3238 return external_name();
3239 }
3240
3241 bool InstanceKlass::is_declared_value_type(int index) {
3242 assert(constants()->is_within_bounds(index) &&
3243 constants()->tag_at(index).is_klass_or_reference(), "Invalid index");
3244 if (value_types() == NULL) return false; // No ValueType attribute in this class file
3245 return InstanceKlass::is_declared_value_type(value_types(), index);
3246 }
3247
3248 bool InstanceKlass::is_declared_value_type(Array<ValueTypes>* value_types, int index) {
3249 assert(value_types != NULL, "Sanity check");
3250 for(int i = 0; i < value_types->length(); i++) {
3251 if (value_types->at(i)._class_info_index == index) {
3252 return true;
3253 }
3254 }
3255 return false;
3256 }
3257
3258 bool InstanceKlass::is_declared_value_type(Symbol* symbol) {
3259 if (value_types() == NULL) return false; // No ValueType attribute in this class file
3260 return InstanceKlass::is_declared_value_type(constants(), value_types(), symbol);
3261 }
3262
3263 bool InstanceKlass::is_declared_value_type(ConstantPool* constants, Array<ValueTypes>* value_types, Symbol* symbol) {
3264 assert(symbol != NULL, "Sanity check");
3265 assert(value_types != NULL, "Sanity check");
3266 for(int i = 0; i < value_types->length(); i++) {
3267 if (value_types->at(i)._class_name == symbol) {
3268 return true;
3269 }
3270 }
3271 // symbol not found, class name symbol might not have been
3272 // updated yet
3273 for(int i = 0; i < value_types->length(); i++) {
3274 if (constants->klass_at_noresolve((int)value_types->at(i)._class_info_index) == symbol) {
3275 value_types->adr_at(i)->_class_name = symbol;
3276 symbol->increment_refcount();
3277 return true;
3278 }
3279 }
3280 return false;
3281 }
3282
3283 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3284 const char* module_name,
3285 const ClassFileStream* cfs) const {
3286 if (!log_is_enabled(Info, class, load)) {
3287 return;
3288 }
3289
3290 ResourceMark rm;
3291 LogMessage(class, load) msg;
3292 stringStream info_stream;
3293
3294 // Name and class hierarchy info
3295 info_stream.print("%s", external_name());
3296
3297 // Source
3298 if (cfs != NULL) {
3299 if (cfs->source() != NULL) {
3300 if (module_name != NULL) {
3301 if (ClassLoader::is_modules_image(cfs->source())) {
3302 info_stream.print(" source: jrt:/%s", module_name);
3303 } else {
3304 info_stream.print(" source: %s", cfs->source());
3305 }
3306 } else {
3307 info_stream.print(" source: %s", cfs->source());
3308 }
3309 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3310 Thread* THREAD = Thread::current();
3311 Klass* caller =
3312 THREAD->is_Java_thread()
3313 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3314 : NULL;
3315 // caller can be NULL, for example, during a JVMTI VM_Init hook
3316 if (caller != NULL) {
3317 info_stream.print(" source: instance of %s", caller->external_name());
3318 } else {
3319 // source is unknown
3320 }
3321 } else {
3322 oop class_loader = loader_data->class_loader();
3323 info_stream.print(" source: %s", class_loader->klass()->external_name());
3324 }
3325 } else {
3326 info_stream.print(" source: shared objects file");
3327 }
3328
3329 msg.info("%s", info_stream.as_string());
3330
3331 if (log_is_enabled(Debug, class, load)) {
3332 stringStream debug_stream;
3333
3334 // Class hierarchy info
3335 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3336 p2i(this), p2i(superklass()));
3337
3338 // Interfaces
3339 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3340 debug_stream.print(" interfaces:");
3341 int length = local_interfaces()->length();
3342 for (int i = 0; i < length; i++) {
3343 debug_stream.print(" " INTPTR_FORMAT,
3344 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3345 }
3346 }
3347
3348 // Class loader
3349 debug_stream.print(" loader: [");
3350 loader_data->print_value_on(&debug_stream);
3351 debug_stream.print("]");
3352
3353 // Classfile checksum
3354 if (cfs) {
3355 debug_stream.print(" bytes: %d checksum: %08x",
3356 cfs->length(),
3357 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3358 cfs->length()));
3359 }
3360
3361 msg.debug("%s", debug_stream.as_string());
3362 }
3363 }
3364
3365 #if INCLUDE_SERVICES
3366 // Size Statistics
3367 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3368 Klass::collect_statistics(sz);
3369
3370 sz->_inst_size = wordSize * size_helper();
3371 sz->_vtab_bytes = wordSize * vtable_length();
3372 sz->_itab_bytes = wordSize * itable_length();
3373 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3374
3375 int n = 0;
3376 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3377 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3378 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3379 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3380 n += (sz->_fields_bytes = sz->count_array(fields()));
3381 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3382 sz->_ro_bytes += n;
3383
3384 const ConstantPool* cp = constants();
3385 if (cp) {
3386 cp->collect_statistics(sz);
3387 }
3388
3389 const Annotations* anno = annotations();
3390 if (anno) {
3391 anno->collect_statistics(sz);
3392 }
3393
3394 const Array<Method*>* methods_array = methods();
3395 if (methods()) {
3396 for (int i = 0; i < methods_array->length(); i++) {
3397 Method* method = methods_array->at(i);
3398 if (method) {
3399 sz->_method_count ++;
3400 method->collect_statistics(sz);
3401 }
3402 }
3403 }
3404 }
3405 #endif // INCLUDE_SERVICES
3406
3407 // Verification
3408
3409 class VerifyFieldClosure: public OopClosure {
3410 protected:
3411 template <class T> void do_oop_work(T* p) {
3412 oop obj = oopDesc::load_decode_heap_oop(p);
3413 if (!oopDesc::is_oop_or_null(obj)) {
3414 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3415 Universe::print_on(tty);
3416 guarantee(false, "boom");
3417 }
3418 }
3419 public:
3420 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3421 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3422 };
3423
3424 void InstanceKlass::verify_on(outputStream* st) {
3425 #ifndef PRODUCT
3426 // Avoid redundant verifies, this really should be in product.
3427 if (_verify_count == Universe::verify_count()) return;
3428 _verify_count = Universe::verify_count();
3429 #endif
3430
3431 // Verify Klass
3432 Klass::verify_on(st);
3433
3434 // Verify that klass is present in ClassLoaderData
3435 guarantee(class_loader_data()->contains_klass(this),
3436 "this class isn't found in class loader data");
3437
3438 // Verify vtables
3439 if (is_linked()) {
3440 // $$$ This used to be done only for m/s collections. Doing it
3441 // always seemed a valid generalization. (DLD -- 6/00)
3442 vtable().verify(st);
3443 }
3444
3445 // Verify first subklass
3446 if (subklass() != NULL) {
3447 guarantee(subklass()->is_klass(), "should be klass");
3448 }
3449
3450 // Verify siblings
3451 Klass* super = this->super();
3452 Klass* sib = next_sibling();
3453 if (sib != NULL) {
3454 if (sib == this) {
3455 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3456 }
3457
3458 guarantee(sib->is_klass(), "should be klass");
3459 guarantee(sib->super() == super, "siblings should have same superklass");
3460 }
3461
3462 // Verify implementor fields
3463 Klass* im = implementor();
3464 if (im != NULL) {
3465 guarantee(is_interface(), "only interfaces should have implementor set");
3466 guarantee(im->is_klass(), "should be klass");
3467 guarantee(!im->is_interface() || im == this,
3468 "implementors cannot be interfaces");
3469 }
3470
3471 // Verify local interfaces
3472 if (local_interfaces()) {
3473 Array<Klass*>* local_interfaces = this->local_interfaces();
3474 for (int j = 0; j < local_interfaces->length(); j++) {
3475 Klass* e = local_interfaces->at(j);
3476 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3477 }
3478 }
3479
3480 // Verify transitive interfaces
3481 if (transitive_interfaces() != NULL) {
3482 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3483 for (int j = 0; j < transitive_interfaces->length(); j++) {
3484 Klass* e = transitive_interfaces->at(j);
3485 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3486 }
3487 }
3488
3489 // Verify methods
3490 if (methods() != NULL) {
3491 Array<Method*>* methods = this->methods();
3492 for (int j = 0; j < methods->length(); j++) {
3493 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3494 }
3495 for (int j = 0; j < methods->length() - 1; j++) {
3496 Method* m1 = methods->at(j);
3497 Method* m2 = methods->at(j + 1);
3498 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3499 }
3500 }
3501
3502 // Verify method ordering
3503 if (method_ordering() != NULL) {
3504 Array<int>* method_ordering = this->method_ordering();
3505 int length = method_ordering->length();
3506 if (JvmtiExport::can_maintain_original_method_order() ||
3507 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3508 guarantee(length == methods()->length(), "invalid method ordering length");
3509 jlong sum = 0;
3510 for (int j = 0; j < length; j++) {
3511 int original_index = method_ordering->at(j);
3512 guarantee(original_index >= 0, "invalid method ordering index");
3513 guarantee(original_index < length, "invalid method ordering index");
3514 sum += original_index;
3515 }
3516 // Verify sum of indices 0,1,...,length-1
3517 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3518 } else {
3519 guarantee(length == 0, "invalid method ordering length");
3520 }
3521 }
3522
3523 // Verify default methods
3524 if (default_methods() != NULL) {
3525 Array<Method*>* methods = this->default_methods();
3526 for (int j = 0; j < methods->length(); j++) {
3527 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3528 }
3529 for (int j = 0; j < methods->length() - 1; j++) {
3530 Method* m1 = methods->at(j);
3531 Method* m2 = methods->at(j + 1);
3532 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3533 }
3534 }
3535
3536 // Verify JNI static field identifiers
3537 if (jni_ids() != NULL) {
3538 jni_ids()->verify(this);
3539 }
3540
3541 // Verify other fields
3542 if (array_klasses() != NULL) {
3543 guarantee(array_klasses()->is_klass(), "should be klass");
3544 }
3545 if (constants() != NULL) {
3546 guarantee(constants()->is_constantPool(), "should be constant pool");
3547 }
3548 const Klass* host = host_klass();
3549 if (host != NULL) {
3550 guarantee(host->is_klass(), "should be klass");
3551 }
3552 }
3553
3554 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3555 Klass::oop_verify_on(obj, st);
3556 VerifyFieldClosure blk;
3557 obj->oop_iterate_no_header(&blk);
3558 }
3559
3560
3561 // JNIid class for jfieldIDs only
3562 // Note to reviewers:
3563 // These JNI functions are just moved over to column 1 and not changed
3564 // in the compressed oops workspace.
3565 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3566 _holder = holder;
3567 _offset = offset;
3568 _next = next;
3569 debug_only(_is_static_field_id = false;)
3570 }
3571
3572
3573 JNIid* JNIid::find(int offset) {
3574 JNIid* current = this;
3575 while (current != NULL) {
3576 if (current->offset() == offset) return current;
3577 current = current->next();
3578 }
3579 return NULL;
3580 }
3581
3582 void JNIid::deallocate(JNIid* current) {
3583 while (current != NULL) {
3584 JNIid* next = current->next();
3585 delete current;
3586 current = next;
3587 }
3588 }
3589
3590
3591 void JNIid::verify(Klass* holder) {
3592 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3593 int end_field_offset;
3594 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3595
3596 JNIid* current = this;
3597 while (current != NULL) {
3598 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3599 #ifdef ASSERT
3600 int o = current->offset();
3601 if (current->is_static_field_id()) {
3602 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3603 }
3604 #endif
3605 current = current->next();
3606 }
3607 }
3608
3609 oop InstanceKlass::klass_holder_phantom() {
3610 oop* addr;
3611 if (is_anonymous()) {
3612 addr = _java_mirror.ptr_raw();
3613 } else {
3614 addr = &class_loader_data()->_class_loader;
3615 }
3616 return RootAccess<IN_CONCURRENT_ROOT | ON_PHANTOM_OOP_REF>::oop_load(addr);
3617 }
3618
3619 #ifdef ASSERT
3620 void InstanceKlass::set_init_state(ClassState state) {
3621 bool good_state = is_shared() ? (_init_state <= state)
3622 : (_init_state < state);
3623 assert(good_state || state == allocated, "illegal state transition");
3624 _init_state = (u1)state;
3625 }
3626 #endif
3627
3628 #if INCLUDE_JVMTI
3629
3630 // RedefineClasses() support for previous versions
3631
3632 // Globally, there is at least one previous version of a class to walk
3633 // during class unloading, which is saved because old methods in the class
3634 // are still running. Otherwise the previous version list is cleaned up.
3635 bool InstanceKlass::_has_previous_versions = false;
3636
3637 // Returns true if there are previous versions of a class for class
3638 // unloading only. Also resets the flag to false. purge_previous_version
3639 // will set the flag to true if there are any left, i.e., if there's any
3640 // work to do for next time. This is to avoid the expensive code cache
3641 // walk in CLDG::do_unloading().
3642 bool InstanceKlass::has_previous_versions_and_reset() {
3643 bool ret = _has_previous_versions;
3644 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3645 ret ? "true" : "false");
3646 _has_previous_versions = false;
3647 return ret;
3648 }
3649
3650 // Purge previous versions before adding new previous versions of the class and
3651 // during class unloading.
3652 void InstanceKlass::purge_previous_version_list() {
3653 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3654 assert(has_been_redefined(), "Should only be called for main class");
3655
3656 // Quick exit.
3657 if (previous_versions() == NULL) {
3658 return;
3659 }
3660
3661 // This klass has previous versions so see what we can cleanup
3662 // while it is safe to do so.
3663
3664 int deleted_count = 0; // leave debugging breadcrumbs
3665 int live_count = 0;
3666 ClassLoaderData* loader_data = class_loader_data();
3667 assert(loader_data != NULL, "should never be null");
3668
3669 ResourceMark rm;
3670 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3671
3672 // previous versions are linked together through the InstanceKlass
3673 InstanceKlass* pv_node = previous_versions();
3674 InstanceKlass* last = this;
3675 int version = 0;
3676
3677 // check the previous versions list
3678 for (; pv_node != NULL; ) {
3679
3680 ConstantPool* pvcp = pv_node->constants();
3681 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3682
3683 if (!pvcp->on_stack()) {
3684 // If the constant pool isn't on stack, none of the methods
3685 // are executing. Unlink this previous_version.
3686 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3687 // so will be deallocated during the next phase of class unloading.
3688 log_trace(redefine, class, iklass, purge)
3689 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3690 // For debugging purposes.
3691 pv_node->set_is_scratch_class();
3692 // Unlink from previous version list.
3693 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3694 InstanceKlass* next = pv_node->previous_versions();
3695 pv_node->link_previous_versions(NULL); // point next to NULL
3696 last->link_previous_versions(next);
3697 // Add to the deallocate list after unlinking
3698 loader_data->add_to_deallocate_list(pv_node);
3699 pv_node = next;
3700 deleted_count++;
3701 version++;
3702 continue;
3703 } else {
3704 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3705 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3706 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3707 live_count++;
3708 // found a previous version for next time we do class unloading
3709 _has_previous_versions = true;
3710 }
3711
3712 // At least one method is live in this previous version.
3713 // Reset dead EMCP methods not to get breakpoints.
3714 // All methods are deallocated when all of the methods for this class are no
3715 // longer running.
3716 Array<Method*>* method_refs = pv_node->methods();
3717 if (method_refs != NULL) {
3718 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3719 for (int j = 0; j < method_refs->length(); j++) {
3720 Method* method = method_refs->at(j);
3721
3722 if (!method->on_stack()) {
3723 // no breakpoints for non-running methods
3724 if (method->is_running_emcp()) {
3725 method->set_running_emcp(false);
3726 }
3727 } else {
3728 assert (method->is_obsolete() || method->is_running_emcp(),
3729 "emcp method cannot run after emcp bit is cleared");
3730 log_trace(redefine, class, iklass, purge)
3731 ("purge: %s(%s): prev method @%d in version @%d is alive",
3732 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3733 }
3734 }
3735 }
3736 // next previous version
3737 last = pv_node;
3738 pv_node = pv_node->previous_versions();
3739 version++;
3740 }
3741 log_trace(redefine, class, iklass, purge)
3742 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3743 }
3744
3745 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3746 int emcp_method_count) {
3747 int obsolete_method_count = old_methods->length() - emcp_method_count;
3748
3749 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3750 _previous_versions != NULL) {
3751 // We have a mix of obsolete and EMCP methods so we have to
3752 // clear out any matching EMCP method entries the hard way.
3753 int local_count = 0;
3754 for (int i = 0; i < old_methods->length(); i++) {
3755 Method* old_method = old_methods->at(i);
3756 if (old_method->is_obsolete()) {
3757 // only obsolete methods are interesting
3758 Symbol* m_name = old_method->name();
3759 Symbol* m_signature = old_method->signature();
3760
3761 // previous versions are linked together through the InstanceKlass
3762 int j = 0;
3763 for (InstanceKlass* prev_version = _previous_versions;
3764 prev_version != NULL;
3765 prev_version = prev_version->previous_versions(), j++) {
3766
3767 Array<Method*>* method_refs = prev_version->methods();
3768 for (int k = 0; k < method_refs->length(); k++) {
3769 Method* method = method_refs->at(k);
3770
3771 if (!method->is_obsolete() &&
3772 method->name() == m_name &&
3773 method->signature() == m_signature) {
3774 // The current RedefineClasses() call has made all EMCP
3775 // versions of this method obsolete so mark it as obsolete
3776 log_trace(redefine, class, iklass, add)
3777 ("%s(%s): flush obsolete method @%d in version @%d",
3778 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3779
3780 method->set_is_obsolete();
3781 break;
3782 }
3783 }
3784
3785 // The previous loop may not find a matching EMCP method, but
3786 // that doesn't mean that we can optimize and not go any
3787 // further back in the PreviousVersion generations. The EMCP
3788 // method for this generation could have already been made obsolete,
3789 // but there still may be an older EMCP method that has not
3790 // been made obsolete.
3791 }
3792
3793 if (++local_count >= obsolete_method_count) {
3794 // no more obsolete methods so bail out now
3795 break;
3796 }
3797 }
3798 }
3799 }
3800 }
3801
3802 // Save the scratch_class as the previous version if any of the methods are running.
3803 // The previous_versions are used to set breakpoints in EMCP methods and they are
3804 // also used to clean MethodData links to redefined methods that are no longer running.
3805 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3806 int emcp_method_count) {
3807 assert(Thread::current()->is_VM_thread(),
3808 "only VMThread can add previous versions");
3809
3810 ResourceMark rm;
3811 log_trace(redefine, class, iklass, add)
3812 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3813
3814 // Clean out old previous versions for this class
3815 purge_previous_version_list();
3816
3817 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3818 // a previous redefinition may be made obsolete by this redefinition.
3819 Array<Method*>* old_methods = scratch_class->methods();
3820 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3821
3822 // If the constant pool for this previous version of the class
3823 // is not marked as being on the stack, then none of the methods
3824 // in this previous version of the class are on the stack so
3825 // we don't need to add this as a previous version.
3826 ConstantPool* cp_ref = scratch_class->constants();
3827 if (!cp_ref->on_stack()) {
3828 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3829 // For debugging purposes.
3830 scratch_class->set_is_scratch_class();
3831 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3832 return;
3833 }
3834
3835 if (emcp_method_count != 0) {
3836 // At least one method is still running, check for EMCP methods
3837 for (int i = 0; i < old_methods->length(); i++) {
3838 Method* old_method = old_methods->at(i);
3839 if (!old_method->is_obsolete() && old_method->on_stack()) {
3840 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3841 // we can add breakpoints for it.
3842
3843 // We set the method->on_stack bit during safepoints for class redefinition
3844 // and use this bit to set the is_running_emcp bit.
3845 // After the safepoint, the on_stack bit is cleared and the running emcp
3846 // method may exit. If so, we would set a breakpoint in a method that
3847 // is never reached, but this won't be noticeable to the programmer.
3848 old_method->set_running_emcp(true);
3849 log_trace(redefine, class, iklass, add)
3850 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3851 } else if (!old_method->is_obsolete()) {
3852 log_trace(redefine, class, iklass, add)
3853 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3854 }
3855 }
3856 }
3857
3858 // Add previous version if any methods are still running.
3859 // Set has_previous_version flag for processing during class unloading.
3860 _has_previous_versions = true;
3861 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3862 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3863 scratch_class->link_previous_versions(previous_versions());
3864 link_previous_versions(scratch_class);
3865 } // end add_previous_version()
3866
3867 #endif // INCLUDE_JVMTI
3868
3869 Method* InstanceKlass::method_with_idnum(int idnum) {
3870 Method* m = NULL;
3871 if (idnum < methods()->length()) {
3872 m = methods()->at(idnum);
3873 }
3874 if (m == NULL || m->method_idnum() != idnum) {
3875 for (int index = 0; index < methods()->length(); ++index) {
3876 m = methods()->at(index);
3877 if (m->method_idnum() == idnum) {
3878 return m;
3879 }
3880 }
3881 // None found, return null for the caller to handle.
3882 return NULL;
3883 }
3884 return m;
3885 }
3886
3887
3888 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3889 if (idnum >= methods()->length()) {
3890 return NULL;
3891 }
3892 Method* m = methods()->at(idnum);
3893 if (m != NULL && m->orig_method_idnum() == idnum) {
3894 return m;
3895 }
3896 // Obsolete method idnum does not match the original idnum
3897 for (int index = 0; index < methods()->length(); ++index) {
3898 m = methods()->at(index);
3899 if (m->orig_method_idnum() == idnum) {
3900 return m;
3901 }
3902 }
3903 // None found, return null for the caller to handle.
3904 return NULL;
3905 }
3906
3907
3908 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3909 InstanceKlass* holder = get_klass_version(version);
3910 if (holder == NULL) {
3911 return NULL; // The version of klass is gone, no method is found
3912 }
3913 Method* method = holder->method_with_orig_idnum(idnum);
3914 return method;
3915 }
3916
3917 #if INCLUDE_JVMTI
3918 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3919 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3920 // Ignore the archived class stream data
3921 return NULL;
3922 } else {
3923 return _cached_class_file;
3924 }
3925 }
3926
3927 jint InstanceKlass::get_cached_class_file_len() {
3928 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3929 }
3930
3931 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3932 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3933 }
3934
3935 #if INCLUDE_CDS
3936 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3937 if (DumpSharedSpaces) {
3938 return _cached_class_file;
3939 } else {
3940 assert(this->is_shared(), "class should be shared");
3941 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3942 return _cached_class_file;
3943 } else {
3944 return NULL;
3945 }
3946 }
3947 }
3948 #endif
3949 #endif
3950
3951 #define THROW_DVT_ERROR(s) \
3952 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), \
3953 "ValueCapableClass class '%s' %s", external_name(),(s)); \
3954 return