1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/javaClasses.hpp"
32 #include "classfile/moduleEntry.hpp"
33 #include "classfile/systemDictionary.hpp"
34 #include "classfile/systemDictionaryShared.hpp"
35 #include "classfile/verifier.hpp"
36 #include "classfile/vmSymbols.hpp"
37 #include "code/dependencyContext.hpp"
38 #include "compiler/compileBroker.hpp"
39 #include "gc/shared/collectedHeap.inline.hpp"
40 #include "gc/shared/specialized_oop_closures.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "interpreter/rewriter.hpp"
43 #include "jvmtifiles/jvmti.h"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/heapInspection.hpp"
48 #include "memory/iterator.inline.hpp"
49 #include "memory/metadataFactory.hpp"
50 #include "memory/metaspaceClosure.hpp"
51 #include "memory/metaspaceShared.hpp"
52 #include "memory/oopFactory.hpp"
53 #include "memory/resourceArea.hpp"
54 #include "oops/fieldStreams.hpp"
55 #include "oops/instanceClassLoaderKlass.hpp"
56 #include "oops/instanceKlass.inline.hpp"
57 #include "oops/instanceMirrorKlass.hpp"
58 #include "oops/instanceOop.hpp"
59 #include "oops/klass.inline.hpp"
60 #include "oops/method.hpp"
61 #include "oops/oop.inline.hpp"
62 #include "oops/symbol.hpp"
63 #include "oops/valueKlass.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "prims/jvmtiRedefineClasses.hpp"
66 #include "prims/jvmtiThreadState.hpp"
67 #include "prims/methodComparator.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/fieldDescriptor.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/javaCalls.hpp"
72 #include "runtime/mutexLocker.hpp"
73 #include "runtime/orderAccess.inline.hpp"
74 #include "runtime/thread.inline.hpp"
75 #include "services/classLoadingService.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/dtrace.hpp"
78 #include "utilities/macros.hpp"
79 #include "utilities/stringUtils.hpp"
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83
84 #ifdef DTRACE_ENABLED
85
86
87 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
88 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
89 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
90 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
91 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
92 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
93 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
94 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
95 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
96 { \
97 char* data = NULL; \
98 int len = 0; \
99 Symbol* clss_name = name(); \
100 if (clss_name != NULL) { \
101 data = (char*)clss_name->bytes(); \
102 len = clss_name->utf8_length(); \
103 } \
104 HOTSPOT_CLASS_INITIALIZATION_##type( \
105 data, len, (void*)class_loader(), thread_type); \
106 }
107
108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
109 { \
110 char* data = NULL; \
111 int len = 0; \
112 Symbol* clss_name = name(); \
113 if (clss_name != NULL) { \
114 data = (char*)clss_name->bytes(); \
115 len = clss_name->utf8_length(); \
116 } \
117 HOTSPOT_CLASS_INITIALIZATION_##type( \
118 data, len, (void*)class_loader(), thread_type, wait); \
119 }
120
121 #else // ndef DTRACE_ENABLED
122
123 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
125
126 #endif // ndef DTRACE_ENABLED
127
128 volatile int InstanceKlass::_total_instanceKlass_count = 0;
129
130 static inline bool is_class_loader(const Symbol* class_name,
131 const ClassFileParser& parser) {
132 assert(class_name != NULL, "invariant");
133
134 if (class_name == vmSymbols::java_lang_ClassLoader()) {
135 return true;
136 }
137
138 if (SystemDictionary::ClassLoader_klass_loaded()) {
139 const Klass* const super_klass = parser.super_klass();
140 if (super_klass != NULL) {
141 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
142 return true;
143 }
144 }
145 }
146 return false;
147 }
148
149 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
150 const int size = InstanceKlass::size(parser.vtable_size(),
151 parser.itable_size(),
152 nonstatic_oop_map_size(parser.total_oop_map_count()),
153 parser.is_interface(),
154 parser.is_anonymous(),
155 should_store_fingerprint(parser.is_anonymous()),
156 parser.has_flattenable_fields() ? parser.java_fields_count() : 0,
157 parser.is_value_type());
158
159 const Symbol* const class_name = parser.class_name();
160 assert(class_name != NULL, "invariant");
161 ClassLoaderData* loader_data = parser.loader_data();
162 assert(loader_data != NULL, "invariant");
163
164 InstanceKlass* ik;
165
166 // Allocation
167 if (REF_NONE == parser.reference_type()) {
168 if (class_name == vmSymbols::java_lang_Class()) {
169 // mirror
170 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
171 } else if (is_class_loader(class_name, parser)) {
172 // class loader
173 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
174 } else if (parser.is_value_type()) {
175 // value type
176 ik = new (loader_data, size, THREAD) ValueKlass(parser);
177 } else {
178 // normal
179 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
180 }
181 } else {
182 // reference
183 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
184 }
185
186 // Check for pending exception before adding to the loader data and incrementing
187 // class count. Can get OOM here.
188 if (HAS_PENDING_EXCEPTION) {
189 return NULL;
190 }
191
192 assert(ik != NULL, "invariant");
193
194 const bool publicize = !parser.is_internal();
195 #ifdef ASSERT
196 assert(ik->size() == size, "");
197 ik->bounds_check((address) ik->start_of_vtable(), false, size);
198 ik->bounds_check((address) ik->start_of_itable(), false, size);
199 ik->bounds_check((address) ik->end_of_itable(), true, size);
200 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
201 #endif //ASSERT
202
203 // Add all classes to our internal class loader list here,
204 // including classes in the bootstrap (NULL) class loader.
205 loader_data->add_class(ik, publicize);
206 Atomic::inc(&_total_instanceKlass_count);
207
208 return ik;
209 }
210
211 #ifndef PRODUCT
212 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
213 const char* bad = NULL;
214 address end = NULL;
215 if (addr < (address)this) {
216 bad = "before";
217 } else if (addr == (address)this) {
218 if (edge_ok) return true;
219 bad = "just before";
220 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
221 if (edge_ok) return true;
222 bad = "just after";
223 } else if (addr > end) {
224 bad = "after";
225 } else {
226 return true;
227 }
228 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
229 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
230 Verbose = WizardMode = true; this->print(); //@@
231 return false;
232 }
233 #endif //PRODUCT
234
235 // copy method ordering from resource area to Metaspace
236 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
237 if (m != NULL) {
238 // allocate a new array and copy contents (memcpy?)
239 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
240 for (int i = 0; i < m->length(); i++) {
241 _method_ordering->at_put(i, m->at(i));
242 }
243 } else {
244 _method_ordering = Universe::the_empty_int_array();
245 }
246 }
247
248 // create a new array of vtable_indices for default methods
249 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
250 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
251 assert(default_vtable_indices() == NULL, "only create once");
252 set_default_vtable_indices(vtable_indices);
253 return vtable_indices;
254 }
255
256 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
257 _static_field_size(parser.static_field_size()),
258 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
259 _itable_len(parser.itable_size()),
260 _reference_type(parser.reference_type()),
261 _extra_flags(0),
262 _adr_valueklass_fixed_block(NULL) {
263 set_vtable_length(parser.vtable_size());
264 set_kind(kind);
265 set_access_flags(parser.access_flags());
266 set_is_anonymous(parser.is_anonymous());
267 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
268 false));
269 if (parser.has_flattenable_fields()) {
270 set_has_value_fields();
271 }
272 _java_fields_count = parser.java_fields_count();
273
274 assert(NULL == _methods, "underlying memory not zeroed?");
275 assert(is_instance_klass(), "is layout incorrect?");
276 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
277 }
278
279 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
280 Array<Method*>* methods) {
281 if (methods != NULL && methods != Universe::the_empty_method_array() &&
282 !methods->is_shared()) {
283 for (int i = 0; i < methods->length(); i++) {
284 Method* method = methods->at(i);
285 if (method == NULL) continue; // maybe null if error processing
286 // Only want to delete methods that are not executing for RedefineClasses.
287 // The previous version will point to them so they're not totally dangling
288 assert (!method->on_stack(), "shouldn't be called with methods on stack");
289 MetadataFactory::free_metadata(loader_data, method);
290 }
291 MetadataFactory::free_array<Method*>(loader_data, methods);
292 }
293 }
294
295 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
296 const Klass* super_klass,
297 Array<Klass*>* local_interfaces,
298 Array<Klass*>* transitive_interfaces) {
299 // Only deallocate transitive interfaces if not empty, same as super class
300 // or same as local interfaces. See code in parseClassFile.
301 Array<Klass*>* ti = transitive_interfaces;
302 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
303 // check that the interfaces don't come from super class
304 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
305 InstanceKlass::cast(super_klass)->transitive_interfaces();
306 if (ti != sti && ti != NULL && !ti->is_shared()) {
307 MetadataFactory::free_array<Klass*>(loader_data, ti);
308 }
309 }
310
311 // local interfaces can be empty
312 if (local_interfaces != Universe::the_empty_klass_array() &&
313 local_interfaces != NULL && !local_interfaces->is_shared()) {
314 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
315 }
316 }
317
318 // This function deallocates the metadata and C heap pointers that the
319 // InstanceKlass points to.
320 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
321
322 // Orphan the mirror first, CMS thinks it's still live.
323 if (java_mirror() != NULL) {
324 java_lang_Class::set_klass(java_mirror(), NULL);
325 }
326
327 // Also remove mirror from handles
328 loader_data->remove_handle(_java_mirror);
329
330 // Need to take this class off the class loader data list.
331 loader_data->remove_class(this);
332
333 // The array_klass for this class is created later, after error handling.
334 // For class redefinition, we keep the original class so this scratch class
335 // doesn't have an array class. Either way, assert that there is nothing
336 // to deallocate.
337 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
338
339 // Release C heap allocated data that this might point to, which includes
340 // reference counting symbol names.
341 release_C_heap_structures();
342
343 deallocate_methods(loader_data, methods());
344 set_methods(NULL);
345
346 if (method_ordering() != NULL &&
347 method_ordering() != Universe::the_empty_int_array() &&
348 !method_ordering()->is_shared()) {
349 MetadataFactory::free_array<int>(loader_data, method_ordering());
350 }
351 set_method_ordering(NULL);
352
353 // default methods can be empty
354 if (default_methods() != NULL &&
355 default_methods() != Universe::the_empty_method_array() &&
356 !default_methods()->is_shared()) {
357 MetadataFactory::free_array<Method*>(loader_data, default_methods());
358 }
359 // Do NOT deallocate the default methods, they are owned by superinterfaces.
360 set_default_methods(NULL);
361
362 // default methods vtable indices can be empty
363 if (default_vtable_indices() != NULL &&
364 !default_vtable_indices()->is_shared()) {
365 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
366 }
367 set_default_vtable_indices(NULL);
368
369
370 // This array is in Klass, but remove it with the InstanceKlass since
371 // this place would be the only caller and it can share memory with transitive
372 // interfaces.
373 if (secondary_supers() != NULL &&
374 secondary_supers() != Universe::the_empty_klass_array() &&
375 secondary_supers() != transitive_interfaces() &&
376 !secondary_supers()->is_shared()) {
377 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
378 }
379 set_secondary_supers(NULL);
380
381 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
382 set_transitive_interfaces(NULL);
383 set_local_interfaces(NULL);
384
385 if (fields() != NULL && !fields()->is_shared()) {
386 MetadataFactory::free_array<jushort>(loader_data, fields());
387 }
388 set_fields(NULL, 0);
389
390 // If a method from a redefined class is using this constant pool, don't
391 // delete it, yet. The new class's previous version will point to this.
392 if (constants() != NULL) {
393 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
394 if (!constants()->is_shared()) {
395 MetadataFactory::free_metadata(loader_data, constants());
396 }
397 // Delete any cached resolution errors for the constant pool
398 SystemDictionary::delete_resolution_error(constants());
399
400 set_constants(NULL);
401 }
402
403 if (inner_classes() != NULL &&
404 inner_classes() != Universe::the_empty_short_array() &&
405 !inner_classes()->is_shared()) {
406 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
407 }
408 set_inner_classes(NULL);
409
410 // We should deallocate the Annotations instance if it's not in shared spaces.
411 if (annotations() != NULL && !annotations()->is_shared()) {
412 MetadataFactory::free_metadata(loader_data, annotations());
413 }
414 set_annotations(NULL);
415 }
416
417 bool InstanceKlass::should_be_initialized() const {
418 return !is_initialized();
419 }
420
421 klassItable InstanceKlass::itable() const {
422 return klassItable(const_cast<InstanceKlass*>(this));
423 }
424
425 void InstanceKlass::eager_initialize(Thread *thread) {
426 if (!EagerInitialization) return;
427
428 if (this->is_not_initialized()) {
429 // abort if the the class has a class initializer
430 if (this->class_initializer() != NULL) return;
431
432 // abort if it is java.lang.Object (initialization is handled in genesis)
433 Klass* super_klass = super();
434 if (super_klass == NULL) return;
435
436 // abort if the super class should be initialized
437 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
438
439 // call body to expose the this pointer
440 eager_initialize_impl();
441 }
442 }
443
444 // JVMTI spec thinks there are signers and protection domain in the
445 // instanceKlass. These accessors pretend these fields are there.
446 // The hprof specification also thinks these fields are in InstanceKlass.
447 oop InstanceKlass::protection_domain() const {
448 // return the protection_domain from the mirror
449 return java_lang_Class::protection_domain(java_mirror());
450 }
451
452 // To remove these from requires an incompatible change and CCC request.
453 objArrayOop InstanceKlass::signers() const {
454 // return the signers from the mirror
455 return java_lang_Class::signers(java_mirror());
456 }
457
458 oop InstanceKlass::init_lock() const {
459 // return the init lock from the mirror
460 oop lock = java_lang_Class::init_lock(java_mirror());
461 // Prevent reordering with any access of initialization state
462 OrderAccess::loadload();
463 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
464 "only fully initialized state can have a null lock");
465 return lock;
466 }
467
468 // Set the initialization lock to null so the object can be GC'ed. Any racing
469 // threads to get this lock will see a null lock and will not lock.
470 // That's okay because they all check for initialized state after getting
471 // the lock and return.
472 void InstanceKlass::fence_and_clear_init_lock() {
473 // make sure previous stores are all done, notably the init_state.
474 OrderAccess::storestore();
475 java_lang_Class::set_init_lock(java_mirror(), NULL);
476 assert(!is_not_initialized(), "class must be initialized now");
477 }
478
479 void InstanceKlass::eager_initialize_impl() {
480 EXCEPTION_MARK;
481 HandleMark hm(THREAD);
482 Handle h_init_lock(THREAD, init_lock());
483 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
484
485 // abort if someone beat us to the initialization
486 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
487
488 ClassState old_state = init_state();
489 link_class_impl(true, THREAD);
490 if (HAS_PENDING_EXCEPTION) {
491 CLEAR_PENDING_EXCEPTION;
492 // Abort if linking the class throws an exception.
493
494 // Use a test to avoid redundantly resetting the state if there's
495 // no change. Set_init_state() asserts that state changes make
496 // progress, whereas here we might just be spinning in place.
497 if (old_state != _init_state)
498 set_init_state(old_state);
499 } else {
500 // linking successfull, mark class as initialized
501 set_init_state(fully_initialized);
502 fence_and_clear_init_lock();
503 // trace
504 if (log_is_enabled(Info, class, init)) {
505 ResourceMark rm(THREAD);
506 log_info(class, init)("[Initialized %s without side effects]", external_name());
507 }
508 }
509 }
510
511
512 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
513 // process. The step comments refers to the procedure described in that section.
514 // Note: implementation moved to static method to expose the this pointer.
515 void InstanceKlass::initialize(TRAPS) {
516 if (this->should_be_initialized()) {
517 initialize_impl(CHECK);
518 // Note: at this point the class may be initialized
519 // OR it may be in the state of being initialized
520 // in case of recursive initialization!
521 } else {
522 assert(is_initialized(), "sanity check");
523 }
524 }
525
526
527 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
528 // 1) Verify the bytecodes
529 Verifier::Mode mode =
530 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
531 return Verifier::verify(this, mode, should_verify_class(), THREAD);
532 }
533
534
535 // Used exclusively by the shared spaces dump mechanism to prevent
536 // classes mapped into the shared regions in new VMs from appearing linked.
537
538 void InstanceKlass::unlink_class() {
539 assert(is_linked(), "must be linked");
540 _init_state = loaded;
541 }
542
543 void InstanceKlass::link_class(TRAPS) {
544 assert(is_loaded(), "must be loaded");
545 if (!is_linked()) {
546 link_class_impl(true, CHECK);
547 }
548 }
549
550 // Called to verify that a class can link during initialization, without
551 // throwing a VerifyError.
552 bool InstanceKlass::link_class_or_fail(TRAPS) {
553 assert(is_loaded(), "must be loaded");
554 if (!is_linked()) {
555 link_class_impl(false, CHECK_false);
556 }
557 return is_linked();
558 }
559
560 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
561 if (DumpSharedSpaces && is_in_error_state()) {
562 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
563 // the class has failed verification. Throwing the NoClassDefFoundError here is just
564 // a convenient way to stop repeat attempts to verify the same (bad) class.
565 //
566 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
567 // if we are executing Java code. This is not a problem for CDS dumping phase since
568 // it doesn't execute any Java code.
569 ResourceMark rm(THREAD);
570 Exceptions::fthrow(THREAD_AND_LOCATION,
571 vmSymbols::java_lang_NoClassDefFoundError(),
572 "Class %s, or one of its supertypes, failed class initialization",
573 external_name());
574 return false;
575 }
576 // return if already verified
577 if (is_linked()) {
578 return true;
579 }
580
581 // Timing
582 // timer handles recursion
583 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
584 JavaThread* jt = (JavaThread*)THREAD;
585
586 // link super class before linking this class
587 Klass* super_klass = super();
588 if (super_klass != NULL) {
589 if (super_klass->is_interface()) { // check if super class is an interface
590 ResourceMark rm(THREAD);
591 Exceptions::fthrow(
592 THREAD_AND_LOCATION,
593 vmSymbols::java_lang_IncompatibleClassChangeError(),
594 "class %s has interface %s as super class",
595 external_name(),
596 super_klass->external_name()
597 );
598 return false;
599 }
600
601 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
602 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
603 }
604
605 // link all interfaces implemented by this class before linking this class
606 Array<Klass*>* interfaces = local_interfaces();
607 int num_interfaces = interfaces->length();
608 for (int index = 0; index < num_interfaces; index++) {
609 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
610 interk->link_class_impl(throw_verifyerror, CHECK_false);
611 }
612
613 // If a value type is referenced by a class (either as a field type or a
614 // method argument or return type) this value type must be loaded during
615 // the linking of this class because size and properties of the value type
616 // must be known in order to be able to perform value type optimizations
617
618 // Note: circular dependencies between value types are not handled yet
619
620 // Note: one case is not handled yet: arrays of value types => FixMe
621
622 // Note: the current implementation is not optimized because the search for
623 // value types is performed on all classes. It would be more efficient to
624 // detect value types during verification and 'tag' the classes for which
625 // value type loading is required. However, this optimization won't be
626 // applicable to classes that are not verified
627
628 // First step: fields
629 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
630 ResourceMark rm(THREAD);
631 if (fs.field_descriptor().access_flags().is_flattenable()) {
632 Symbol* signature = fs.field_descriptor().signature();
633 // Get current loader and protection domain first.
634 oop loader = class_loader();
635 oop prot_domain = protection_domain();
636 Klass* klass = SystemDictionary::resolve_or_fail(signature,
637 Handle(THREAD, loader), Handle(THREAD, prot_domain), true,
638 THREAD);
639 if (klass == NULL) {
640 THROW_(vmSymbols::java_lang_LinkageError(), false);
641 }
642 }
643 }
644
645 // Second step: methods arguments and return types
646 // for (int i = 0; i < this_k->constants()->length(); i++) {
647 // if (this_k->constants()->tag_at(i).is_method()) {
648 // Symbol* signature = this_k->constants()->signature_ref_at(i);
649 // ResourceMark rm(THREAD);
650 // for (SignatureStream ss(signature); !ss.is_done(); ss.next()) {
651 // if (ss.type() == T_VALUETYPE) {
652 // Symbol* sig = ss.as_symbol(THREAD);
653 // // Get current loader and protection domain first.
654 // oop loader = this_k->class_loader();
655 // oop protection_domain = this_k->protection_domain();
656 //
657 // bool ok = SystemDictionary::resolve_or_fail(sig,
658 // Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
659 // THREAD);
660 // if (!ok) {
661 // THROW_(vmSymbols::java_lang_LinkageError(), false);
662 // }
663 // }
664 // }
665 // }
666 // }
667
668 // in case the class is linked in the process of linking its superclasses
669 if (is_linked()) {
670 return true;
671 }
672
673 // trace only the link time for this klass that includes
674 // the verification time
675 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
676 ClassLoader::perf_class_link_selftime(),
677 ClassLoader::perf_classes_linked(),
678 jt->get_thread_stat()->perf_recursion_counts_addr(),
679 jt->get_thread_stat()->perf_timers_addr(),
680 PerfClassTraceTime::CLASS_LINK);
681
682 // verification & rewriting
683 {
684 HandleMark hm(THREAD);
685 Handle h_init_lock(THREAD, init_lock());
686 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
687 // rewritten will have been set if loader constraint error found
688 // on an earlier link attempt
689 // don't verify or rewrite if already rewritten
690 //
691
692 if (!is_linked()) {
693 if (!is_rewritten()) {
694 {
695 bool verify_ok = verify_code(throw_verifyerror, THREAD);
696 if (!verify_ok) {
697 return false;
698 }
699 }
700
701 // Just in case a side-effect of verify linked this class already
702 // (which can sometimes happen since the verifier loads classes
703 // using custom class loaders, which are free to initialize things)
704 if (is_linked()) {
705 return true;
706 }
707
708 // also sets rewritten
709 rewrite_class(CHECK_false);
710 } else if (is_shared()) {
711 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
712 }
713
714 // relocate jsrs and link methods after they are all rewritten
715 link_methods(CHECK_false);
716
717 // Initialize the vtable and interface table after
718 // methods have been rewritten since rewrite may
719 // fabricate new Method*s.
720 // also does loader constraint checking
721 //
722 // initialize_vtable and initialize_itable need to be rerun for
723 // a shared class if the class is not loaded by the NULL classloader.
724 ClassLoaderData * loader_data = class_loader_data();
725 if (!(is_shared() &&
726 loader_data->is_the_null_class_loader_data())) {
727 ResourceMark rm(THREAD);
728 vtable().initialize_vtable(true, CHECK_false);
729 itable().initialize_itable(true, CHECK_false);
730 }
731 #ifdef ASSERT
732 else {
733 vtable().verify(tty, true);
734 // In case itable verification is ever added.
735 // itable().verify(tty, true);
736 }
737 #endif
738
739 set_init_state(linked);
740 if (JvmtiExport::should_post_class_prepare()) {
741 Thread *thread = THREAD;
742 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
743 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
744 }
745 }
746 }
747 return true;
748 }
749
750
751 // Rewrite the byte codes of all of the methods of a class.
752 // The rewriter must be called exactly once. Rewriting must happen after
753 // verification but before the first method of the class is executed.
754 void InstanceKlass::rewrite_class(TRAPS) {
755 assert(is_loaded(), "must be loaded");
756 if (is_rewritten()) {
757 assert(is_shared(), "rewriting an unshared class?");
758 return;
759 }
760 Rewriter::rewrite(this, CHECK);
761 set_rewritten();
762 }
763
764 // Now relocate and link method entry points after class is rewritten.
765 // This is outside is_rewritten flag. In case of an exception, it can be
766 // executed more than once.
767 void InstanceKlass::link_methods(TRAPS) {
768 int len = methods()->length();
769 for (int i = len-1; i >= 0; i--) {
770 methodHandle m(THREAD, methods()->at(i));
771
772 // Set up method entry points for compiler and interpreter .
773 m->link_method(m, CHECK);
774 }
775 }
776
777 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
778 void InstanceKlass::initialize_super_interfaces(TRAPS) {
779 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
780 for (int i = 0; i < local_interfaces()->length(); ++i) {
781 Klass* iface = local_interfaces()->at(i);
782 InstanceKlass* ik = InstanceKlass::cast(iface);
783
784 // Initialization is depth first search ie. we start with top of the inheritance tree
785 // has_nonstatic_concrete_methods drives searching superinterfaces since it
786 // means has_nonstatic_concrete_methods in its superinterface hierarchy
787 if (ik->has_nonstatic_concrete_methods()) {
788 ik->initialize_super_interfaces(CHECK);
789 }
790
791 // Only initialize() interfaces that "declare" concrete methods.
792 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
793 ik->initialize(CHECK);
794 }
795 }
796 }
797
798 void InstanceKlass::initialize_impl(TRAPS) {
799 HandleMark hm(THREAD);
800
801 // Make sure klass is linked (verified) before initialization
802 // A class could already be verified, since it has been reflected upon.
803 link_class(CHECK);
804
805 DTRACE_CLASSINIT_PROBE(required, -1);
806
807 bool wait = false;
808
809 // refer to the JVM book page 47 for description of steps
810 // Step 1
811 {
812 Handle h_init_lock(THREAD, init_lock());
813 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
814
815 Thread *self = THREAD; // it's passed the current thread
816
817 // Step 2
818 // If we were to use wait() instead of waitInterruptibly() then
819 // we might end up throwing IE from link/symbol resolution sites
820 // that aren't expected to throw. This would wreak havoc. See 6320309.
821 while(is_being_initialized() && !is_reentrant_initialization(self)) {
822 wait = true;
823 ol.waitUninterruptibly(CHECK);
824 }
825
826 // Step 3
827 if (is_being_initialized() && is_reentrant_initialization(self)) {
828 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
829 return;
830 }
831
832 // Step 4
833 if (is_initialized()) {
834 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
835 return;
836 }
837
838 // Step 5
839 if (is_in_error_state()) {
840 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
841 ResourceMark rm(THREAD);
842 const char* desc = "Could not initialize class ";
843 const char* className = external_name();
844 size_t msglen = strlen(desc) + strlen(className) + 1;
845 char* message = NEW_RESOURCE_ARRAY(char, msglen);
846 if (NULL == message) {
847 // Out of memory: can't create detailed error message
848 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
849 } else {
850 jio_snprintf(message, msglen, "%s%s", desc, className);
851 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
852 }
853 }
854
855 // Step 6
856 set_init_state(being_initialized);
857 set_init_thread(self);
858 }
859
860 // Step 7
861 // Next, if C is a class rather than an interface, initialize it's super class and super
862 // interfaces.
863 if (!is_interface()) {
864 Klass* super_klass = super();
865 if (super_klass != NULL && super_klass->should_be_initialized()) {
866 super_klass->initialize(THREAD);
867 }
868 // If C implements any interface that declares a non-static, concrete method,
869 // the initialization of C triggers initialization of its super interfaces.
870 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
871 // having a superinterface that declares, non-static, concrete methods
872 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
873 initialize_super_interfaces(THREAD);
874 }
875
876 // If any exceptions, complete abruptly, throwing the same exception as above.
877 if (HAS_PENDING_EXCEPTION) {
878 Handle e(THREAD, PENDING_EXCEPTION);
879 CLEAR_PENDING_EXCEPTION;
880 {
881 EXCEPTION_MARK;
882 // Locks object, set state, and notify all waiting threads
883 set_initialization_state_and_notify(initialization_error, THREAD);
884 CLEAR_PENDING_EXCEPTION;
885 }
886 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
887 THROW_OOP(e());
888 }
889 }
890
891
892 // Look for aot compiled methods for this klass, including class initializer.
893 AOTLoader::load_for_klass(this, THREAD);
894
895 // Step 8
896 {
897 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
898 JavaThread* jt = (JavaThread*)THREAD;
899 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
900 // Timer includes any side effects of class initialization (resolution,
901 // etc), but not recursive entry into call_class_initializer().
902 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
903 ClassLoader::perf_class_init_selftime(),
904 ClassLoader::perf_classes_inited(),
905 jt->get_thread_stat()->perf_recursion_counts_addr(),
906 jt->get_thread_stat()->perf_timers_addr(),
907 PerfClassTraceTime::CLASS_CLINIT);
908 call_class_initializer(THREAD);
909 }
910
911 // Step 9
912 if (!HAS_PENDING_EXCEPTION) {
913 set_initialization_state_and_notify(fully_initialized, CHECK);
914 {
915 debug_only(vtable().verify(tty, true);)
916 }
917 }
918 else {
919 // Step 10 and 11
920 Handle e(THREAD, PENDING_EXCEPTION);
921 CLEAR_PENDING_EXCEPTION;
922 // JVMTI has already reported the pending exception
923 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
924 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
925 {
926 EXCEPTION_MARK;
927 set_initialization_state_and_notify(initialization_error, THREAD);
928 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
929 // JVMTI has already reported the pending exception
930 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
931 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
932 }
933 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
934 if (e->is_a(SystemDictionary::Error_klass())) {
935 THROW_OOP(e());
936 } else {
937 JavaCallArguments args(e);
938 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
939 vmSymbols::throwable_void_signature(),
940 &args);
941 }
942 }
943 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
944 }
945
946
947 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
948 Handle h_init_lock(THREAD, init_lock());
949 if (h_init_lock() != NULL) {
950 ObjectLocker ol(h_init_lock, THREAD);
951 set_init_state(state);
952 fence_and_clear_init_lock();
953 ol.notify_all(CHECK);
954 } else {
955 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
956 set_init_state(state);
957 }
958 }
959
960 // The embedded _implementor field can only record one implementor.
961 // When there are more than one implementors, the _implementor field
962 // is set to the interface Klass* itself. Following are the possible
963 // values for the _implementor field:
964 // NULL - no implementor
965 // implementor Klass* - one implementor
966 // self - more than one implementor
967 //
968 // The _implementor field only exists for interfaces.
969 void InstanceKlass::add_implementor(Klass* k) {
970 assert(Compile_lock->owned_by_self(), "");
971 assert(is_interface(), "not interface");
972 // Filter out my subinterfaces.
973 // (Note: Interfaces are never on the subklass list.)
974 if (InstanceKlass::cast(k)->is_interface()) return;
975
976 // Filter out subclasses whose supers already implement me.
977 // (Note: CHA must walk subclasses of direct implementors
978 // in order to locate indirect implementors.)
979 Klass* sk = k->super();
980 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
981 // We only need to check one immediate superclass, since the
982 // implements_interface query looks at transitive_interfaces.
983 // Any supers of the super have the same (or fewer) transitive_interfaces.
984 return;
985
986 Klass* ik = implementor();
987 if (ik == NULL) {
988 set_implementor(k);
989 } else if (ik != this) {
990 // There is already an implementor. Use itself as an indicator of
991 // more than one implementors.
992 set_implementor(this);
993 }
994
995 // The implementor also implements the transitive_interfaces
996 for (int index = 0; index < local_interfaces()->length(); index++) {
997 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
998 }
999 }
1000
1001 void InstanceKlass::init_implementor() {
1002 if (is_interface()) {
1003 set_implementor(NULL);
1004 }
1005 }
1006
1007
1008 void InstanceKlass::process_interfaces(Thread *thread) {
1009 // link this class into the implementors list of every interface it implements
1010 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1011 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1012 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1013 assert(interf->is_interface(), "expected interface");
1014 interf->add_implementor(this);
1015 }
1016 }
1017
1018 bool InstanceKlass::can_be_primary_super_slow() const {
1019 if (is_interface())
1020 return false;
1021 else
1022 return Klass::can_be_primary_super_slow();
1023 }
1024
1025 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1026 // The secondaries are the implemented interfaces.
1027 Array<Klass*>* interfaces = transitive_interfaces();
1028 int num_secondaries = num_extra_slots + interfaces->length();
1029 if (num_secondaries == 0) {
1030 // Must share this for correct bootstrapping!
1031 set_secondary_supers(Universe::the_empty_klass_array());
1032 return NULL;
1033 } else if (num_extra_slots == 0) {
1034 // The secondary super list is exactly the same as the transitive interfaces.
1035 // Redefine classes has to be careful not to delete this!
1036 set_secondary_supers(interfaces);
1037 return NULL;
1038 } else {
1039 // Copy transitive interfaces to a temporary growable array to be constructed
1040 // into the secondary super list with extra slots.
1041 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1042 for (int i = 0; i < interfaces->length(); i++) {
1043 secondaries->push(interfaces->at(i));
1044 }
1045 return secondaries;
1046 }
1047 }
1048
1049 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1050 if (k->is_interface()) {
1051 return implements_interface(k);
1052 } else {
1053 return Klass::compute_is_subtype_of(k);
1054 }
1055 }
1056
1057 bool InstanceKlass::implements_interface(Klass* k) const {
1058 if (this == k) return true;
1059 assert(k->is_interface(), "should be an interface class");
1060 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1061 if (transitive_interfaces()->at(i) == k) {
1062 return true;
1063 }
1064 }
1065 return false;
1066 }
1067
1068 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1069 // Verify direct super interface
1070 if (this == k) return true;
1071 assert(k->is_interface(), "should be an interface class");
1072 for (int i = 0; i < local_interfaces()->length(); i++) {
1073 if (local_interfaces()->at(i) == k) {
1074 return true;
1075 }
1076 }
1077 return false;
1078 }
1079
1080 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1081 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1082 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1083 report_java_out_of_memory("Requested array size exceeds VM limit");
1084 JvmtiExport::post_array_size_exhausted();
1085 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1086 }
1087 int size = objArrayOopDesc::object_size(length);
1088 Klass* ak = array_klass(n, CHECK_NULL);
1089 objArrayOop o =
1090 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1091 return o;
1092 }
1093
1094 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1095 if (TraceFinalizerRegistration) {
1096 tty->print("Registered ");
1097 i->print_value_on(tty);
1098 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1099 }
1100 instanceHandle h_i(THREAD, i);
1101 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1102 JavaValue result(T_VOID);
1103 JavaCallArguments args(h_i);
1104 methodHandle mh (THREAD, Universe::finalizer_register_method());
1105 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1106 return h_i();
1107 }
1108
1109 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1110 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1111 int size = size_helper(); // Query before forming handle.
1112
1113 instanceOop i;
1114
1115 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1116 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1117 i = register_finalizer(i, CHECK_NULL);
1118 }
1119 return i;
1120 }
1121
1122 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1123 if (is_interface() || is_abstract()) {
1124 ResourceMark rm(THREAD);
1125 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1126 : vmSymbols::java_lang_InstantiationException(), external_name());
1127 }
1128 if (this == SystemDictionary::Class_klass()) {
1129 ResourceMark rm(THREAD);
1130 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1131 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1132 }
1133 }
1134
1135 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1136 // Need load-acquire for lock-free read
1137 if (array_klasses_acquire() == NULL) {
1138 if (or_null) return NULL;
1139
1140 ResourceMark rm;
1141 JavaThread *jt = (JavaThread *)THREAD;
1142 {
1143 // Atomic creation of array_klasses
1144 MutexLocker mc(Compile_lock, THREAD); // for vtables
1145 MutexLocker ma(MultiArray_lock, THREAD);
1146
1147 // Check if update has already taken place
1148 if (array_klasses() == NULL) {
1149 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1150 // use 'release' to pair with lock-free load
1151 release_set_array_klasses(k);
1152 }
1153 }
1154 }
1155 // _this will always be set at this point
1156 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1157 if (or_null) {
1158 return oak->array_klass_or_null(n);
1159 }
1160 return oak->array_klass(n, THREAD);
1161 }
1162
1163 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1164 return array_klass_impl(or_null, 1, THREAD);
1165 }
1166
1167 static int call_class_initializer_counter = 0; // for debugging
1168
1169 Method* InstanceKlass::class_initializer() const {
1170 Method* clinit = find_method(
1171 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1172 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1173 return clinit;
1174 }
1175 return NULL;
1176 }
1177
1178 void InstanceKlass::call_class_initializer(TRAPS) {
1179 if (ReplayCompiles &&
1180 (ReplaySuppressInitializers == 1 ||
1181 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1182 // Hide the existence of the initializer for the purpose of replaying the compile
1183 return;
1184 }
1185
1186 methodHandle h_method(THREAD, class_initializer());
1187 assert(!is_initialized(), "we cannot initialize twice");
1188 LogTarget(Info, class, init) lt;
1189 if (lt.is_enabled()) {
1190 ResourceMark rm;
1191 LogStream ls(lt);
1192 ls.print("%d Initializing ", call_class_initializer_counter++);
1193 name()->print_value_on(&ls);
1194 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1195 }
1196 if (h_method() != NULL) {
1197 JavaCallArguments args; // No arguments
1198 JavaValue result(T_VOID);
1199 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1200 }
1201 }
1202
1203
1204 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1205 InterpreterOopMap* entry_for) {
1206 // Lazily create the _oop_map_cache at first request
1207 // Lock-free access requires load_acquire.
1208 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1209 if (oop_map_cache == NULL) {
1210 MutexLockerEx x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1211 // Check if _oop_map_cache was allocated while we were waiting for this lock
1212 if ((oop_map_cache = _oop_map_cache) == NULL) {
1213 oop_map_cache = new OopMapCache();
1214 // Ensure _oop_map_cache is stable, since it is examined without a lock
1215 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1216 }
1217 }
1218 // _oop_map_cache is constant after init; lookup below does its own locking.
1219 oop_map_cache->lookup(method, bci, entry_for);
1220 }
1221
1222
1223 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1224 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1225 Symbol* f_name = fs.name();
1226 Symbol* f_sig = fs.signature();
1227 if (f_name == name && f_sig == sig) {
1228 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1229 return true;
1230 }
1231 }
1232 return false;
1233 }
1234
1235
1236 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1237 const int n = local_interfaces()->length();
1238 for (int i = 0; i < n; i++) {
1239 Klass* intf1 = local_interfaces()->at(i);
1240 assert(intf1->is_interface(), "just checking type");
1241 // search for field in current interface
1242 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1243 assert(fd->is_static(), "interface field must be static");
1244 return intf1;
1245 }
1246 // search for field in direct superinterfaces
1247 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1248 if (intf2 != NULL) return intf2;
1249 }
1250 // otherwise field lookup fails
1251 return NULL;
1252 }
1253
1254
1255 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1256 // search order according to newest JVM spec (5.4.3.2, p.167).
1257 // 1) search for field in current klass
1258 if (find_local_field(name, sig, fd)) {
1259 return const_cast<InstanceKlass*>(this);
1260 }
1261 // 2) search for field recursively in direct superinterfaces
1262 { Klass* intf = find_interface_field(name, sig, fd);
1263 if (intf != NULL) return intf;
1264 }
1265 // 3) apply field lookup recursively if superclass exists
1266 { Klass* supr = super();
1267 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1268 }
1269 // 4) otherwise field lookup fails
1270 return NULL;
1271 }
1272
1273
1274 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1275 // search order according to newest JVM spec (5.4.3.2, p.167).
1276 // 1) search for field in current klass
1277 if (find_local_field(name, sig, fd)) {
1278 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1279 }
1280 // 2) search for field recursively in direct superinterfaces
1281 if (is_static) {
1282 Klass* intf = find_interface_field(name, sig, fd);
1283 if (intf != NULL) return intf;
1284 }
1285 // 3) apply field lookup recursively if superclass exists
1286 { Klass* supr = super();
1287 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1288 }
1289 // 4) otherwise field lookup fails
1290 return NULL;
1291 }
1292
1293
1294 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1295 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1296 if (fs.offset() == offset) {
1297 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1298 if (fd->is_static() == is_static) return true;
1299 }
1300 }
1301 return false;
1302 }
1303
1304
1305 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1306 Klass* klass = const_cast<InstanceKlass*>(this);
1307 while (klass != NULL) {
1308 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1309 return true;
1310 }
1311 klass = klass->super();
1312 }
1313 return false;
1314 }
1315
1316
1317 void InstanceKlass::methods_do(void f(Method* method)) {
1318 // Methods aren't stable until they are loaded. This can be read outside
1319 // a lock through the ClassLoaderData for profiling
1320 if (!is_loaded()) {
1321 return;
1322 }
1323
1324 int len = methods()->length();
1325 for (int index = 0; index < len; index++) {
1326 Method* m = methods()->at(index);
1327 assert(m->is_method(), "must be method");
1328 f(m);
1329 }
1330 }
1331
1332
1333 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1334 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1335 if (fs.access_flags().is_static()) {
1336 fieldDescriptor& fd = fs.field_descriptor();
1337 cl->do_field(&fd);
1338 }
1339 }
1340 }
1341
1342
1343 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1344 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1345 if (fs.access_flags().is_static()) {
1346 fieldDescriptor& fd = fs.field_descriptor();
1347 f(&fd, mirror, CHECK);
1348 }
1349 }
1350 }
1351
1352
1353 static int compare_fields_by_offset(int* a, int* b) {
1354 return a[0] - b[0];
1355 }
1356
1357 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1358 InstanceKlass* super = superklass();
1359 if (super != NULL) {
1360 super->do_nonstatic_fields(cl);
1361 }
1362 fieldDescriptor fd;
1363 int length = java_fields_count();
1364 // In DebugInfo nonstatic fields are sorted by offset.
1365 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1366 int j = 0;
1367 for (int i = 0; i < length; i += 1) {
1368 fd.reinitialize(this, i);
1369 if (!fd.is_static()) {
1370 fields_sorted[j + 0] = fd.offset();
1371 fields_sorted[j + 1] = i;
1372 j += 2;
1373 }
1374 }
1375 if (j > 0) {
1376 length = j;
1377 // _sort_Fn is defined in growableArray.hpp.
1378 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1379 for (int i = 0; i < length; i += 2) {
1380 fd.reinitialize(this, fields_sorted[i + 1]);
1381 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1382 cl->do_field(&fd);
1383 }
1384 }
1385 FREE_C_HEAP_ARRAY(int, fields_sorted);
1386 }
1387
1388
1389 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1390 if (array_klasses() != NULL)
1391 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1392 }
1393
1394 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1395 if (array_klasses() != NULL)
1396 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1397 }
1398
1399 #ifdef ASSERT
1400 static int linear_search(const Array<Method*>* methods,
1401 const Symbol* name,
1402 const Symbol* signature) {
1403 const int len = methods->length();
1404 for (int index = 0; index < len; index++) {
1405 const Method* const m = methods->at(index);
1406 assert(m->is_method(), "must be method");
1407 if (m->signature() == signature && m->name() == name) {
1408 return index;
1409 }
1410 }
1411 return -1;
1412 }
1413 #endif
1414
1415 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1416 int len = methods->length();
1417 // methods are sorted, so do binary search
1418 int l = 0;
1419 int h = len - 1;
1420 while (l <= h) {
1421 int mid = (l + h) >> 1;
1422 Method* m = methods->at(mid);
1423 assert(m->is_method(), "must be method");
1424 int res = m->name()->fast_compare(name);
1425 if (res == 0) {
1426 return mid;
1427 } else if (res < 0) {
1428 l = mid + 1;
1429 } else {
1430 h = mid - 1;
1431 }
1432 }
1433 return -1;
1434 }
1435
1436 // find_method looks up the name/signature in the local methods array
1437 Method* InstanceKlass::find_method(const Symbol* name,
1438 const Symbol* signature) const {
1439 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1440 }
1441
1442 Method* InstanceKlass::find_method_impl(const Symbol* name,
1443 const Symbol* signature,
1444 OverpassLookupMode overpass_mode,
1445 StaticLookupMode static_mode,
1446 PrivateLookupMode private_mode) const {
1447 return InstanceKlass::find_method_impl(methods(),
1448 name,
1449 signature,
1450 overpass_mode,
1451 static_mode,
1452 private_mode);
1453 }
1454
1455 // find_instance_method looks up the name/signature in the local methods array
1456 // and skips over static methods
1457 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1458 const Symbol* name,
1459 const Symbol* signature) {
1460 Method* const meth = InstanceKlass::find_method_impl(methods,
1461 name,
1462 signature,
1463 find_overpass,
1464 skip_static,
1465 find_private);
1466 assert(((meth == NULL) || !meth->is_static()),
1467 "find_instance_method should have skipped statics");
1468 return meth;
1469 }
1470
1471 // find_instance_method looks up the name/signature in the local methods array
1472 // and skips over static methods
1473 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1474 return InstanceKlass::find_instance_method(methods(), name, signature);
1475 }
1476
1477 // Find looks up the name/signature in the local methods array
1478 // and filters on the overpass, static and private flags
1479 // This returns the first one found
1480 // note that the local methods array can have up to one overpass, one static
1481 // and one instance (private or not) with the same name/signature
1482 Method* InstanceKlass::find_local_method(const Symbol* name,
1483 const Symbol* signature,
1484 OverpassLookupMode overpass_mode,
1485 StaticLookupMode static_mode,
1486 PrivateLookupMode private_mode) const {
1487 return InstanceKlass::find_method_impl(methods(),
1488 name,
1489 signature,
1490 overpass_mode,
1491 static_mode,
1492 private_mode);
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 Array<Method*>* methods,
1501 const Symbol* name,
1502 const Symbol* signature,
1503 OverpassLookupMode overpass_mode,
1504 StaticLookupMode static_mode,
1505 PrivateLookupMode private_mode) {
1506 return InstanceKlass::find_method_impl(methods,
1507 name,
1508 signature,
1509 overpass_mode,
1510 static_mode,
1511 private_mode);
1512 }
1513
1514 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1515 const Symbol* name,
1516 const Symbol* signature) {
1517 return InstanceKlass::find_method_impl(methods,
1518 name,
1519 signature,
1520 find_overpass,
1521 find_static,
1522 find_private);
1523 }
1524
1525 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1526 const Symbol* name,
1527 const Symbol* signature,
1528 OverpassLookupMode overpass_mode,
1529 StaticLookupMode static_mode,
1530 PrivateLookupMode private_mode) {
1531 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1532 return hit >= 0 ? methods->at(hit): NULL;
1533 }
1534
1535 // true if method matches signature and conforms to skipping_X conditions.
1536 static bool method_matches(const Method* m,
1537 const Symbol* signature,
1538 bool skipping_overpass,
1539 bool skipping_static,
1540 bool skipping_private) {
1541 return ((m->signature() == signature) &&
1542 (!skipping_overpass || !m->is_overpass()) &&
1543 (!skipping_static || !m->is_static()) &&
1544 (!skipping_private || !m->is_private()));
1545 }
1546
1547 // Used directly for default_methods to find the index into the
1548 // default_vtable_indices, and indirectly by find_method
1549 // find_method_index looks in the local methods array to return the index
1550 // of the matching name/signature. If, overpass methods are being ignored,
1551 // the search continues to find a potential non-overpass match. This capability
1552 // is important during method resolution to prefer a static method, for example,
1553 // over an overpass method.
1554 // There is the possibility in any _method's array to have the same name/signature
1555 // for a static method, an overpass method and a local instance method
1556 // To correctly catch a given method, the search criteria may need
1557 // to explicitly skip the other two. For local instance methods, it
1558 // is often necessary to skip private methods
1559 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1560 const Symbol* name,
1561 const Symbol* signature,
1562 OverpassLookupMode overpass_mode,
1563 StaticLookupMode static_mode,
1564 PrivateLookupMode private_mode) {
1565 const bool skipping_overpass = (overpass_mode == skip_overpass);
1566 const bool skipping_static = (static_mode == skip_static);
1567 const bool skipping_private = (private_mode == skip_private);
1568 const int hit = binary_search(methods, name);
1569 if (hit != -1) {
1570 const Method* const m = methods->at(hit);
1571
1572 // Do linear search to find matching signature. First, quick check
1573 // for common case, ignoring overpasses if requested.
1574 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1575 return hit;
1576 }
1577
1578 // search downwards through overloaded methods
1579 int i;
1580 for (i = hit - 1; i >= 0; --i) {
1581 const Method* const m = methods->at(i);
1582 assert(m->is_method(), "must be method");
1583 if (m->name() != name) {
1584 break;
1585 }
1586 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1587 return i;
1588 }
1589 }
1590 // search upwards
1591 for (i = hit + 1; i < methods->length(); ++i) {
1592 const Method* const m = methods->at(i);
1593 assert(m->is_method(), "must be method");
1594 if (m->name() != name) {
1595 break;
1596 }
1597 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1598 return i;
1599 }
1600 }
1601 // not found
1602 #ifdef ASSERT
1603 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1604 linear_search(methods, name, signature);
1605 assert(-1 == index, "binary search should have found entry %d", index);
1606 #endif
1607 }
1608 return -1;
1609 }
1610
1611 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1612 return find_method_by_name(methods(), name, end);
1613 }
1614
1615 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1616 const Symbol* name,
1617 int* end_ptr) {
1618 assert(end_ptr != NULL, "just checking");
1619 int start = binary_search(methods, name);
1620 int end = start + 1;
1621 if (start != -1) {
1622 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1623 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1624 *end_ptr = end;
1625 return start;
1626 }
1627 return -1;
1628 }
1629
1630 // uncached_lookup_method searches both the local class methods array and all
1631 // superclasses methods arrays, skipping any overpass methods in superclasses.
1632 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1633 const Symbol* signature,
1634 OverpassLookupMode overpass_mode) const {
1635 OverpassLookupMode overpass_local_mode = overpass_mode;
1636 const Klass* klass = this;
1637 while (klass != NULL) {
1638 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1639 signature,
1640 overpass_local_mode,
1641 find_static,
1642 find_private);
1643 if (method != NULL) {
1644 return method;
1645 }
1646 klass = klass->super();
1647 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1648 }
1649 return NULL;
1650 }
1651
1652 #ifdef ASSERT
1653 // search through class hierarchy and return true if this class or
1654 // one of the superclasses was redefined
1655 bool InstanceKlass::has_redefined_this_or_super() const {
1656 const Klass* klass = this;
1657 while (klass != NULL) {
1658 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1659 return true;
1660 }
1661 klass = klass->super();
1662 }
1663 return false;
1664 }
1665 #endif
1666
1667 // lookup a method in the default methods list then in all transitive interfaces
1668 // Do NOT return private or static methods
1669 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1670 Symbol* signature) const {
1671 Method* m = NULL;
1672 if (default_methods() != NULL) {
1673 m = find_method(default_methods(), name, signature);
1674 }
1675 // Look up interfaces
1676 if (m == NULL) {
1677 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1678 }
1679 return m;
1680 }
1681
1682 // lookup a method in all the interfaces that this class implements
1683 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1684 // They should only be found in the initial InterfaceMethodRef
1685 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1686 Symbol* signature,
1687 DefaultsLookupMode defaults_mode) const {
1688 Array<Klass*>* all_ifs = transitive_interfaces();
1689 int num_ifs = all_ifs->length();
1690 InstanceKlass *ik = NULL;
1691 for (int i = 0; i < num_ifs; i++) {
1692 ik = InstanceKlass::cast(all_ifs->at(i));
1693 Method* m = ik->lookup_method(name, signature);
1694 if (m != NULL && m->is_public() && !m->is_static() &&
1695 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1696 return m;
1697 }
1698 }
1699 return NULL;
1700 }
1701
1702 /* jni_id_for_impl for jfieldIds only */
1703 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1704 MutexLocker ml(JfieldIdCreation_lock);
1705 // Retry lookup after we got the lock
1706 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1707 if (probe == NULL) {
1708 // Slow case, allocate new static field identifier
1709 probe = new JNIid(this, offset, jni_ids());
1710 set_jni_ids(probe);
1711 }
1712 return probe;
1713 }
1714
1715
1716 /* jni_id_for for jfieldIds only */
1717 JNIid* InstanceKlass::jni_id_for(int offset) {
1718 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1719 if (probe == NULL) {
1720 probe = jni_id_for_impl(offset);
1721 }
1722 return probe;
1723 }
1724
1725 u2 InstanceKlass::enclosing_method_data(int offset) const {
1726 const Array<jushort>* const inner_class_list = inner_classes();
1727 if (inner_class_list == NULL) {
1728 return 0;
1729 }
1730 const int length = inner_class_list->length();
1731 if (length % inner_class_next_offset == 0) {
1732 return 0;
1733 }
1734 const int index = length - enclosing_method_attribute_size;
1735 assert(offset < enclosing_method_attribute_size, "invalid offset");
1736 return inner_class_list->at(index + offset);
1737 }
1738
1739 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1740 u2 method_index) {
1741 Array<jushort>* inner_class_list = inner_classes();
1742 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1743 int length = inner_class_list->length();
1744 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1745 int index = length - enclosing_method_attribute_size;
1746 inner_class_list->at_put(
1747 index + enclosing_method_class_index_offset, class_index);
1748 inner_class_list->at_put(
1749 index + enclosing_method_method_index_offset, method_index);
1750 }
1751 }
1752
1753 // Lookup or create a jmethodID.
1754 // This code is called by the VMThread and JavaThreads so the
1755 // locking has to be done very carefully to avoid deadlocks
1756 // and/or other cache consistency problems.
1757 //
1758 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1759 size_t idnum = (size_t)method_h->method_idnum();
1760 jmethodID* jmeths = methods_jmethod_ids_acquire();
1761 size_t length = 0;
1762 jmethodID id = NULL;
1763
1764 // We use a double-check locking idiom here because this cache is
1765 // performance sensitive. In the normal system, this cache only
1766 // transitions from NULL to non-NULL which is safe because we use
1767 // release_set_methods_jmethod_ids() to advertise the new cache.
1768 // A partially constructed cache should never be seen by a racing
1769 // thread. We also use release_store() to save a new jmethodID
1770 // in the cache so a partially constructed jmethodID should never be
1771 // seen either. Cache reads of existing jmethodIDs proceed without a
1772 // lock, but cache writes of a new jmethodID requires uniqueness and
1773 // creation of the cache itself requires no leaks so a lock is
1774 // generally acquired in those two cases.
1775 //
1776 // If the RedefineClasses() API has been used, then this cache can
1777 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1778 // Cache creation requires no leaks and we require safety between all
1779 // cache accesses and freeing of the old cache so a lock is generally
1780 // acquired when the RedefineClasses() API has been used.
1781
1782 if (jmeths != NULL) {
1783 // the cache already exists
1784 if (!idnum_can_increment()) {
1785 // the cache can't grow so we can just get the current values
1786 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1787 } else {
1788 // cache can grow so we have to be more careful
1789 if (Threads::number_of_threads() == 0 ||
1790 SafepointSynchronize::is_at_safepoint()) {
1791 // we're single threaded or at a safepoint - no locking needed
1792 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1793 } else {
1794 MutexLocker ml(JmethodIdCreation_lock);
1795 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1796 }
1797 }
1798 }
1799 // implied else:
1800 // we need to allocate a cache so default length and id values are good
1801
1802 if (jmeths == NULL || // no cache yet
1803 length <= idnum || // cache is too short
1804 id == NULL) { // cache doesn't contain entry
1805
1806 // This function can be called by the VMThread so we have to do all
1807 // things that might block on a safepoint before grabbing the lock.
1808 // Otherwise, we can deadlock with the VMThread or have a cache
1809 // consistency issue. These vars keep track of what we might have
1810 // to free after the lock is dropped.
1811 jmethodID to_dealloc_id = NULL;
1812 jmethodID* to_dealloc_jmeths = NULL;
1813
1814 // may not allocate new_jmeths or use it if we allocate it
1815 jmethodID* new_jmeths = NULL;
1816 if (length <= idnum) {
1817 // allocate a new cache that might be used
1818 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1819 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1820 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1821 // cache size is stored in element[0], other elements offset by one
1822 new_jmeths[0] = (jmethodID)size;
1823 }
1824
1825 // allocate a new jmethodID that might be used
1826 jmethodID new_id = NULL;
1827 if (method_h->is_old() && !method_h->is_obsolete()) {
1828 // The method passed in is old (but not obsolete), we need to use the current version
1829 Method* current_method = method_with_idnum((int)idnum);
1830 assert(current_method != NULL, "old and but not obsolete, so should exist");
1831 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1832 } else {
1833 // It is the current version of the method or an obsolete method,
1834 // use the version passed in
1835 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1836 }
1837
1838 if (Threads::number_of_threads() == 0 ||
1839 SafepointSynchronize::is_at_safepoint()) {
1840 // we're single threaded or at a safepoint - no locking needed
1841 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1842 &to_dealloc_id, &to_dealloc_jmeths);
1843 } else {
1844 MutexLocker ml(JmethodIdCreation_lock);
1845 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1846 &to_dealloc_id, &to_dealloc_jmeths);
1847 }
1848
1849 // The lock has been dropped so we can free resources.
1850 // Free up either the old cache or the new cache if we allocated one.
1851 if (to_dealloc_jmeths != NULL) {
1852 FreeHeap(to_dealloc_jmeths);
1853 }
1854 // free up the new ID since it wasn't needed
1855 if (to_dealloc_id != NULL) {
1856 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1857 }
1858 }
1859 return id;
1860 }
1861
1862 // Figure out how many jmethodIDs haven't been allocated, and make
1863 // sure space for them is pre-allocated. This makes getting all
1864 // method ids much, much faster with classes with more than 8
1865 // methods, and has a *substantial* effect on performance with jvmti
1866 // code that loads all jmethodIDs for all classes.
1867 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1868 int new_jmeths = 0;
1869 int length = methods()->length();
1870 for (int index = start_offset; index < length; index++) {
1871 Method* m = methods()->at(index);
1872 jmethodID id = m->find_jmethod_id_or_null();
1873 if (id == NULL) {
1874 new_jmeths++;
1875 }
1876 }
1877 if (new_jmeths != 0) {
1878 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1879 }
1880 }
1881
1882 // Common code to fetch the jmethodID from the cache or update the
1883 // cache with the new jmethodID. This function should never do anything
1884 // that causes the caller to go to a safepoint or we can deadlock with
1885 // the VMThread or have cache consistency issues.
1886 //
1887 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1888 size_t idnum, jmethodID new_id,
1889 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1890 jmethodID** to_dealloc_jmeths_p) {
1891 assert(new_id != NULL, "sanity check");
1892 assert(to_dealloc_id_p != NULL, "sanity check");
1893 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1894 assert(Threads::number_of_threads() == 0 ||
1895 SafepointSynchronize::is_at_safepoint() ||
1896 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1897
1898 // reacquire the cache - we are locked, single threaded or at a safepoint
1899 jmethodID* jmeths = methods_jmethod_ids_acquire();
1900 jmethodID id = NULL;
1901 size_t length = 0;
1902
1903 if (jmeths == NULL || // no cache yet
1904 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1905 if (jmeths != NULL) {
1906 // copy any existing entries from the old cache
1907 for (size_t index = 0; index < length; index++) {
1908 new_jmeths[index+1] = jmeths[index+1];
1909 }
1910 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1911 }
1912 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1913 } else {
1914 // fetch jmethodID (if any) from the existing cache
1915 id = jmeths[idnum+1];
1916 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1917 }
1918 if (id == NULL) {
1919 // No matching jmethodID in the existing cache or we have a new
1920 // cache or we just grew the cache. This cache write is done here
1921 // by the first thread to win the foot race because a jmethodID
1922 // needs to be unique once it is generally available.
1923 id = new_id;
1924
1925 // The jmethodID cache can be read while unlocked so we have to
1926 // make sure the new jmethodID is complete before installing it
1927 // in the cache.
1928 OrderAccess::release_store(&jmeths[idnum+1], id);
1929 } else {
1930 *to_dealloc_id_p = new_id; // save new id for later delete
1931 }
1932 return id;
1933 }
1934
1935
1936 // Common code to get the jmethodID cache length and the jmethodID
1937 // value at index idnum if there is one.
1938 //
1939 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1940 size_t idnum, size_t *length_p, jmethodID* id_p) {
1941 assert(cache != NULL, "sanity check");
1942 assert(length_p != NULL, "sanity check");
1943 assert(id_p != NULL, "sanity check");
1944
1945 // cache size is stored in element[0], other elements offset by one
1946 *length_p = (size_t)cache[0];
1947 if (*length_p <= idnum) { // cache is too short
1948 *id_p = NULL;
1949 } else {
1950 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1951 }
1952 }
1953
1954
1955 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1956 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1957 size_t idnum = (size_t)method->method_idnum();
1958 jmethodID* jmeths = methods_jmethod_ids_acquire();
1959 size_t length; // length assigned as debugging crumb
1960 jmethodID id = NULL;
1961 if (jmeths != NULL && // If there is a cache
1962 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1963 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1964 }
1965 return id;
1966 }
1967
1968 inline DependencyContext InstanceKlass::dependencies() {
1969 DependencyContext dep_context(&_dep_context);
1970 return dep_context;
1971 }
1972
1973 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1974 return dependencies().mark_dependent_nmethods(changes);
1975 }
1976
1977 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1978 dependencies().add_dependent_nmethod(nm);
1979 }
1980
1981 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1982 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1983 }
1984
1985 #ifndef PRODUCT
1986 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1987 dependencies().print_dependent_nmethods(verbose);
1988 }
1989
1990 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1991 return dependencies().is_dependent_nmethod(nm);
1992 }
1993 #endif //PRODUCT
1994
1995 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
1996 clean_implementors_list(is_alive);
1997 clean_method_data(is_alive);
1998
1999 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2000 DependencyContext dep_context(&_dep_context);
2001 dep_context.expunge_stale_entries();
2002 }
2003
2004 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2005 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2006 if (is_interface()) {
2007 if (ClassUnloading) {
2008 Klass* impl = implementor();
2009 if (impl != NULL) {
2010 if (!impl->is_loader_alive(is_alive)) {
2011 // remove this guy
2012 Klass** klass = adr_implementor();
2013 assert(klass != NULL, "null klass");
2014 if (klass != NULL) {
2015 *klass = NULL;
2016 }
2017 }
2018 }
2019 }
2020 }
2021 }
2022
2023 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2024 for (int m = 0; m < methods()->length(); m++) {
2025 MethodData* mdo = methods()->at(m)->method_data();
2026 if (mdo != NULL) {
2027 mdo->clean_method_data(is_alive);
2028 }
2029 }
2030 }
2031
2032 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2033 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2034 ResourceMark rm;
2035 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2036 return false;
2037 }
2038
2039 Array<Klass*>* local_interfaces = this->local_interfaces();
2040 if (local_interfaces != NULL) {
2041 int length = local_interfaces->length();
2042 for (int i = 0; i < length; i++) {
2043 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2044 if (!intf->has_passed_fingerprint_check()) {
2045 ResourceMark rm;
2046 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2047 return false;
2048 }
2049 }
2050 }
2051
2052 return true;
2053 }
2054
2055 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) {
2056 #if INCLUDE_AOT
2057 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2058 if (CalculateClassFingerprint) {
2059 // (1) We are running AOT to generate a shared library.
2060 return true;
2061 }
2062 if (DumpSharedSpaces) {
2063 // (2) We are running -Xshare:dump to create a shared archive
2064 return true;
2065 }
2066 if (UseAOT && is_anonymous) {
2067 // (3) We are using AOT code from a shared library and see an anonymous class
2068 return true;
2069 }
2070 #endif
2071
2072 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2073 // but do not store the 64-bit fingerprint to save space.
2074 return false;
2075 }
2076
2077 bool InstanceKlass::has_stored_fingerprint() const {
2078 #if INCLUDE_AOT
2079 return should_store_fingerprint() || is_shared();
2080 #else
2081 return false;
2082 #endif
2083 }
2084
2085 uint64_t InstanceKlass::get_stored_fingerprint() const {
2086 address adr = adr_fingerprint();
2087 if (adr != NULL) {
2088 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2089 }
2090 return 0;
2091 }
2092
2093 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2094 address adr = adr_fingerprint();
2095 if (adr != NULL) {
2096 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2097
2098 ResourceMark rm;
2099 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2100 }
2101 }
2102
2103 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2104 Klass::metaspace_pointers_do(it);
2105
2106 if (log_is_enabled(Trace, cds)) {
2107 ResourceMark rm;
2108 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2109 }
2110
2111 it->push(&_annotations);
2112 it->push((Klass**)&_array_klasses);
2113 it->push(&_constants);
2114 it->push(&_inner_classes);
2115 it->push(&_array_name);
2116 #if INCLUDE_JVMTI
2117 it->push(&_previous_versions);
2118 #endif
2119 it->push(&_methods);
2120 it->push(&_default_methods);
2121 it->push(&_local_interfaces);
2122 it->push(&_transitive_interfaces);
2123 it->push(&_method_ordering);
2124 it->push(&_default_vtable_indices);
2125 it->push(&_fields);
2126
2127 if (itable_length() > 0) {
2128 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2129 int method_table_offset_in_words = ioe->offset()/wordSize;
2130 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2131 / itableOffsetEntry::size();
2132
2133 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2134 if (ioe->interface_klass() != NULL) {
2135 it->push(ioe->interface_klass_addr());
2136 itableMethodEntry* ime = ioe->first_method_entry(this);
2137 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2138 for (int index = 0; index < n; index ++) {
2139 it->push(ime[index].method_addr());
2140 }
2141 }
2142 }
2143 }
2144 }
2145
2146 void InstanceKlass::remove_unshareable_info() {
2147 Klass::remove_unshareable_info();
2148
2149 if (is_in_error_state()) {
2150 // Classes are attempted to link during dumping and may fail,
2151 // but these classes are still in the dictionary and class list in CLD.
2152 // Check in_error state first because in_error is > linked state, so
2153 // is_linked() is true.
2154 // If there's a linking error, there is nothing else to remove.
2155 return;
2156 }
2157
2158 // Unlink the class
2159 if (is_linked()) {
2160 unlink_class();
2161 }
2162 init_implementor();
2163
2164 constants()->remove_unshareable_info();
2165
2166 for (int i = 0; i < methods()->length(); i++) {
2167 Method* m = methods()->at(i);
2168 m->remove_unshareable_info();
2169 }
2170
2171 // do array classes also.
2172 if (array_klasses() != NULL) {
2173 array_klasses()->remove_unshareable_info();
2174 }
2175
2176 // These are not allocated from metaspace, but they should should all be empty
2177 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2178 guarantee(_source_debug_extension == NULL, "must be");
2179 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2180 guarantee(_osr_nmethods_head == NULL, "must be");
2181
2182 #if INCLUDE_JVMTI
2183 guarantee(_breakpoints == NULL, "must be");
2184 guarantee(_previous_versions == NULL, "must be");
2185 #endif
2186
2187 _init_thread = NULL;
2188 _methods_jmethod_ids = NULL;
2189 _jni_ids = NULL;
2190 _oop_map_cache = NULL;
2191 }
2192
2193 void InstanceKlass::remove_java_mirror() {
2194 Klass::remove_java_mirror();
2195
2196 // do array classes also.
2197 if (array_klasses() != NULL) {
2198 array_klasses()->remove_java_mirror();
2199 }
2200 }
2201
2202 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2203 set_package(loader_data, CHECK);
2204 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2205
2206 Array<Method*>* methods = this->methods();
2207 int num_methods = methods->length();
2208 for (int index2 = 0; index2 < num_methods; ++index2) {
2209 methodHandle m(THREAD, methods->at(index2));
2210 m->restore_unshareable_info(CHECK);
2211 }
2212 if (JvmtiExport::has_redefined_a_class()) {
2213 // Reinitialize vtable because RedefineClasses may have changed some
2214 // entries in this vtable for super classes so the CDS vtable might
2215 // point to old or obsolete entries. RedefineClasses doesn't fix up
2216 // vtables in the shared system dictionary, only the main one.
2217 // It also redefines the itable too so fix that too.
2218 ResourceMark rm(THREAD);
2219 vtable().initialize_vtable(false, CHECK);
2220 itable().initialize_itable(false, CHECK);
2221 }
2222
2223 // restore constant pool resolved references
2224 constants()->restore_unshareable_info(CHECK);
2225
2226 if (array_klasses() != NULL) {
2227 // Array classes have null protection domain.
2228 // --> see ArrayKlass::complete_create_array_klass()
2229 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2230 }
2231 }
2232
2233 // returns true IFF is_in_error_state() has been changed as a result of this call.
2234 bool InstanceKlass::check_sharing_error_state() {
2235 assert(DumpSharedSpaces, "should only be called during dumping");
2236 bool old_state = is_in_error_state();
2237
2238 if (!is_in_error_state()) {
2239 bool bad = false;
2240 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2241 if (sup->is_in_error_state()) {
2242 bad = true;
2243 break;
2244 }
2245 }
2246 if (!bad) {
2247 Array<Klass*>* interfaces = transitive_interfaces();
2248 for (int i = 0; i < interfaces->length(); i++) {
2249 Klass* iface = interfaces->at(i);
2250 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2251 bad = true;
2252 break;
2253 }
2254 }
2255 }
2256
2257 if (bad) {
2258 set_in_error_state();
2259 }
2260 }
2261
2262 return (old_state != is_in_error_state());
2263 }
2264
2265 #if INCLUDE_JVMTI
2266 static void clear_all_breakpoints(Method* m) {
2267 m->clear_all_breakpoints();
2268 }
2269 #endif
2270
2271 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2272 // notify the debugger
2273 if (JvmtiExport::should_post_class_unload()) {
2274 JvmtiExport::post_class_unload(ik);
2275 }
2276
2277 // notify ClassLoadingService of class unload
2278 ClassLoadingService::notify_class_unloaded(ik);
2279 }
2280
2281 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2282 // Clean up C heap
2283 ik->release_C_heap_structures();
2284 ik->constants()->release_C_heap_structures();
2285 }
2286
2287 void InstanceKlass::release_C_heap_structures() {
2288 // Can't release the constant pool here because the constant pool can be
2289 // deallocated separately from the InstanceKlass for default methods and
2290 // redefine classes.
2291
2292 // Deallocate oop map cache
2293 if (_oop_map_cache != NULL) {
2294 delete _oop_map_cache;
2295 _oop_map_cache = NULL;
2296 }
2297
2298 // Deallocate JNI identifiers for jfieldIDs
2299 JNIid::deallocate(jni_ids());
2300 set_jni_ids(NULL);
2301
2302 jmethodID* jmeths = methods_jmethod_ids_acquire();
2303 if (jmeths != (jmethodID*)NULL) {
2304 release_set_methods_jmethod_ids(NULL);
2305 FreeHeap(jmeths);
2306 }
2307
2308 // Release dependencies.
2309 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2310 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2311 // context can contain live dependencies, since there's a race between nmethod &
2312 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2313 // dependencies aren't removed from the context associated with the class (see
2314 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2315 // live dependencies pointing to unloaded nmethods and causes a crash in
2316 // DC::remove_all_dependents() when it touches unloaded nmethod.
2317 dependencies().wipe();
2318
2319 #if INCLUDE_JVMTI
2320 // Deallocate breakpoint records
2321 if (breakpoints() != 0x0) {
2322 methods_do(clear_all_breakpoints);
2323 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2324 }
2325
2326 // deallocate the cached class file
2327 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2328 os::free(_cached_class_file);
2329 _cached_class_file = NULL;
2330 }
2331 #endif
2332
2333 // Decrement symbol reference counts associated with the unloaded class.
2334 if (_name != NULL) _name->decrement_refcount();
2335 // unreference array name derived from this class name (arrays of an unloaded
2336 // class can't be referenced anymore).
2337 if (_array_name != NULL) _array_name->decrement_refcount();
2338 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2339
2340 assert(_total_instanceKlass_count >= 1, "Sanity check");
2341 Atomic::dec(&_total_instanceKlass_count);
2342 }
2343
2344 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2345 if (array == NULL) {
2346 _source_debug_extension = NULL;
2347 } else {
2348 // Adding one to the attribute length in order to store a null terminator
2349 // character could cause an overflow because the attribute length is
2350 // already coded with an u4 in the classfile, but in practice, it's
2351 // unlikely to happen.
2352 assert((length+1) > length, "Overflow checking");
2353 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2354 for (int i = 0; i < length; i++) {
2355 sde[i] = array[i];
2356 }
2357 sde[length] = '\0';
2358 _source_debug_extension = sde;
2359 }
2360 }
2361
2362 address InstanceKlass::static_field_addr(int offset) {
2363 assert(offset >= InstanceMirrorKlass::offset_of_static_fields(), "has already been adjusted");
2364 return (address)(offset + cast_from_oop<intptr_t>(java_mirror()));
2365 }
2366
2367
2368 const char* InstanceKlass::signature_name() const {
2369 int hash_len = 0;
2370 char hash_buf[40];
2371
2372 // If this is an anonymous class, append a hash to make the name unique
2373 if (is_anonymous()) {
2374 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2375 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2376 hash_len = (int)strlen(hash_buf);
2377 }
2378
2379 // Get the internal name as a c string
2380 const char* src = (const char*) (name()->as_C_string());
2381 const int src_length = (int)strlen(src);
2382
2383 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2384
2385 // Add L as type indicator
2386 int dest_index = 0;
2387 dest[dest_index++] = 'L';
2388
2389 // Add the actual class name
2390 for (int src_index = 0; src_index < src_length; ) {
2391 dest[dest_index++] = src[src_index++];
2392 }
2393
2394 // If we have a hash, append it
2395 for (int hash_index = 0; hash_index < hash_len; ) {
2396 dest[dest_index++] = hash_buf[hash_index++];
2397 }
2398
2399 // Add the semicolon and the NULL
2400 dest[dest_index++] = ';';
2401 dest[dest_index] = '\0';
2402 return dest;
2403 }
2404
2405 // Used to obtain the package name from a fully qualified class name.
2406 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2407 if (name == NULL) {
2408 return NULL;
2409 } else {
2410 if (name->utf8_length() <= 0) {
2411 return NULL;
2412 }
2413 ResourceMark rm;
2414 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2415 if (package_name == NULL) {
2416 return NULL;
2417 }
2418 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2419 return pkg_name;
2420 }
2421 }
2422
2423 ModuleEntry* InstanceKlass::module() const {
2424 if (!in_unnamed_package()) {
2425 return _package_entry->module();
2426 }
2427 const Klass* host = host_klass();
2428 if (host == NULL) {
2429 return class_loader_data()->unnamed_module();
2430 }
2431 return host->class_loader_data()->unnamed_module();
2432 }
2433
2434 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2435
2436 // ensure java/ packages only loaded by boot or platform builtin loaders
2437 Handle class_loader(THREAD, loader_data->class_loader());
2438 check_prohibited_package(name(), class_loader, CHECK);
2439
2440 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2441
2442 if (pkg_name != NULL && loader_data != NULL) {
2443
2444 // Find in class loader's package entry table.
2445 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2446
2447 // If the package name is not found in the loader's package
2448 // entry table, it is an indication that the package has not
2449 // been defined. Consider it defined within the unnamed module.
2450 if (_package_entry == NULL) {
2451 ResourceMark rm;
2452
2453 if (!ModuleEntryTable::javabase_defined()) {
2454 // Before java.base is defined during bootstrapping, define all packages in
2455 // the java.base module. If a non-java.base package is erroneously placed
2456 // in the java.base module it will be caught later when java.base
2457 // is defined by ModuleEntryTable::verify_javabase_packages check.
2458 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2459 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2460 } else {
2461 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2462 _package_entry = loader_data->packages()->lookup(pkg_name,
2463 loader_data->unnamed_module());
2464 }
2465
2466 // A package should have been successfully created
2467 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2468 name()->as_C_string(), loader_data->loader_name());
2469 }
2470
2471 if (log_is_enabled(Debug, module)) {
2472 ResourceMark rm;
2473 ModuleEntry* m = _package_entry->module();
2474 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2475 external_name(),
2476 pkg_name->as_C_string(),
2477 loader_data->loader_name(),
2478 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2479 }
2480 } else {
2481 ResourceMark rm;
2482 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2483 external_name(),
2484 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2485 UNNAMED_MODULE);
2486 }
2487 }
2488
2489
2490 // different versions of is_same_class_package
2491
2492 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2493 oop classloader1 = this->class_loader();
2494 PackageEntry* classpkg1 = this->package();
2495 if (class2->is_objArray_klass()) {
2496 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2497 }
2498
2499 oop classloader2;
2500 PackageEntry* classpkg2;
2501 if (class2->is_instance_klass()) {
2502 classloader2 = class2->class_loader();
2503 classpkg2 = class2->package();
2504 } else {
2505 assert(class2->is_typeArray_klass(), "should be type array");
2506 classloader2 = NULL;
2507 classpkg2 = NULL;
2508 }
2509
2510 // Same package is determined by comparing class loader
2511 // and package entries. Both must be the same. This rule
2512 // applies even to classes that are defined in the unnamed
2513 // package, they still must have the same class loader.
2514 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2515 return true;
2516 }
2517
2518 return false;
2519 }
2520
2521 // return true if this class and other_class are in the same package. Classloader
2522 // and classname information is enough to determine a class's package
2523 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2524 const Symbol* other_class_name) const {
2525 if (class_loader() != other_class_loader) {
2526 return false;
2527 }
2528 if (name()->fast_compare(other_class_name) == 0) {
2529 return true;
2530 }
2531
2532 {
2533 ResourceMark rm;
2534
2535 bool bad_class_name = false;
2536 const char* other_pkg =
2537 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2538 if (bad_class_name) {
2539 return false;
2540 }
2541 // Check that package_from_name() returns NULL, not "", if there is no package.
2542 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2543
2544 const Symbol* const this_package_name =
2545 this->package() != NULL ? this->package()->name() : NULL;
2546
2547 if (this_package_name == NULL || other_pkg == NULL) {
2548 // One of the two doesn't have a package. Only return true if the other
2549 // one also doesn't have a package.
2550 return (const char*)this_package_name == other_pkg;
2551 }
2552
2553 // Check if package is identical
2554 return this_package_name->equals(other_pkg);
2555 }
2556 }
2557
2558 // Returns true iff super_method can be overridden by a method in targetclassname
2559 // See JLS 3rd edition 8.4.6.1
2560 // Assumes name-signature match
2561 // "this" is InstanceKlass of super_method which must exist
2562 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2563 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2564 // Private methods can not be overridden
2565 if (super_method->is_private()) {
2566 return false;
2567 }
2568 // If super method is accessible, then override
2569 if ((super_method->is_protected()) ||
2570 (super_method->is_public())) {
2571 return true;
2572 }
2573 // Package-private methods are not inherited outside of package
2574 assert(super_method->is_package_private(), "must be package private");
2575 return(is_same_class_package(targetclassloader(), targetclassname));
2576 }
2577
2578 // Only boot and platform class loaders can define classes in "java/" packages.
2579 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2580 Handle class_loader,
2581 TRAPS) {
2582 if (!class_loader.is_null() &&
2583 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2584 class_name != NULL) {
2585 ResourceMark rm(THREAD);
2586 char* name = class_name->as_C_string();
2587 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2588 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2589 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2590 name = pkg_name->as_C_string();
2591 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2592 StringUtils::replace_no_expand(name, "/", ".");
2593 const char* msg_text1 = "Class loader (instance of): ";
2594 const char* msg_text2 = " tried to load prohibited package name: ";
2595 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2596 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2597 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2598 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2599 }
2600 }
2601 return;
2602 }
2603
2604 // tell if two classes have the same enclosing class (at package level)
2605 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2606 if (class2 == this) return true;
2607 if (!class2->is_instance_klass()) return false;
2608
2609 // must be in same package before we try anything else
2610 if (!is_same_class_package(class2))
2611 return false;
2612
2613 // As long as there is an outer_this.getEnclosingClass,
2614 // shift the search outward.
2615 const InstanceKlass* outer_this = this;
2616 for (;;) {
2617 // As we walk along, look for equalities between outer_this and class2.
2618 // Eventually, the walks will terminate as outer_this stops
2619 // at the top-level class around the original class.
2620 bool ignore_inner_is_member;
2621 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2622 CHECK_false);
2623 if (next == NULL) break;
2624 if (next == class2) return true;
2625 outer_this = InstanceKlass::cast(next);
2626 }
2627
2628 // Now do the same for class2.
2629 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2630 for (;;) {
2631 bool ignore_inner_is_member;
2632 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2633 CHECK_false);
2634 if (next == NULL) break;
2635 // Might as well check the new outer against all available values.
2636 if (next == this) return true;
2637 if (next == outer_this) return true;
2638 outer2 = InstanceKlass::cast(next);
2639 }
2640
2641 // If by this point we have not found an equality between the
2642 // two classes, we know they are in separate package members.
2643 return false;
2644 }
2645
2646 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2647 constantPoolHandle i_cp(THREAD, constants());
2648 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2649 int ioff = iter.inner_class_info_index();
2650 if (ioff != 0) {
2651 // Check to see if the name matches the class we're looking for
2652 // before attempting to find the class.
2653 if (i_cp->klass_name_at_matches(this, ioff)) {
2654 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2655 if (this == inner_klass) {
2656 *ooff = iter.outer_class_info_index();
2657 *noff = iter.inner_name_index();
2658 return true;
2659 }
2660 }
2661 }
2662 }
2663 return false;
2664 }
2665
2666 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2667 InstanceKlass* outer_klass = NULL;
2668 *inner_is_member = false;
2669 int ooff = 0, noff = 0;
2670 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2671 if (has_inner_classes_attr) {
2672 constantPoolHandle i_cp(THREAD, constants());
2673 if (ooff != 0) {
2674 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2675 outer_klass = InstanceKlass::cast(ok);
2676 *inner_is_member = true;
2677 }
2678 if (NULL == outer_klass) {
2679 // It may be anonymous; try for that.
2680 int encl_method_class_idx = enclosing_method_class_index();
2681 if (encl_method_class_idx != 0) {
2682 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2683 outer_klass = InstanceKlass::cast(ok);
2684 *inner_is_member = false;
2685 }
2686 }
2687 }
2688
2689 // If no inner class attribute found for this class.
2690 if (NULL == outer_klass) return NULL;
2691
2692 // Throws an exception if outer klass has not declared k as an inner klass
2693 // We need evidence that each klass knows about the other, or else
2694 // the system could allow a spoof of an inner class to gain access rights.
2695 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2696 return outer_klass;
2697 }
2698
2699 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2700 jint access = access_flags().as_int();
2701
2702 // But check if it happens to be member class.
2703 InnerClassesIterator iter(this);
2704 for (; !iter.done(); iter.next()) {
2705 int ioff = iter.inner_class_info_index();
2706 // Inner class attribute can be zero, skip it.
2707 // Strange but true: JVM spec. allows null inner class refs.
2708 if (ioff == 0) continue;
2709
2710 // only look at classes that are already loaded
2711 // since we are looking for the flags for our self.
2712 Symbol* inner_name = constants()->klass_name_at(ioff);
2713 if (name() == inner_name) {
2714 // This is really a member class.
2715 access = iter.inner_access_flags();
2716 break;
2717 }
2718 }
2719 // Remember to strip ACC_SUPER bit
2720 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2721 }
2722
2723 jint InstanceKlass::jvmti_class_status() const {
2724 jint result = 0;
2725
2726 if (is_linked()) {
2727 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2728 }
2729
2730 if (is_initialized()) {
2731 assert(is_linked(), "Class status is not consistent");
2732 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2733 }
2734 if (is_in_error_state()) {
2735 result |= JVMTI_CLASS_STATUS_ERROR;
2736 }
2737 return result;
2738 }
2739
2740 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2741 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2742 int method_table_offset_in_words = ioe->offset()/wordSize;
2743 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2744 / itableOffsetEntry::size();
2745
2746 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2747 // If the interface isn't implemented by the receiver class,
2748 // the VM should throw IncompatibleClassChangeError.
2749 if (cnt >= nof_interfaces) {
2750 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2751 }
2752
2753 Klass* ik = ioe->interface_klass();
2754 if (ik == holder) break;
2755 }
2756
2757 itableMethodEntry* ime = ioe->first_method_entry(this);
2758 Method* m = ime[index].method();
2759 if (m == NULL) {
2760 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2761 }
2762 return m;
2763 }
2764
2765
2766 #if INCLUDE_JVMTI
2767 // update default_methods for redefineclasses for methods that are
2768 // not yet in the vtable due to concurrent subclass define and superinterface
2769 // redefinition
2770 // Note: those in the vtable, should have been updated via adjust_method_entries
2771 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2772 // search the default_methods for uses of either obsolete or EMCP methods
2773 if (default_methods() != NULL) {
2774 for (int index = 0; index < default_methods()->length(); index ++) {
2775 Method* old_method = default_methods()->at(index);
2776 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2777 continue; // skip uninteresting entries
2778 }
2779 assert(!old_method->is_deleted(), "default methods may not be deleted");
2780
2781 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2782
2783 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2784 assert(old_method != new_method, "sanity check");
2785
2786 default_methods()->at_put(index, new_method);
2787 if (log_is_enabled(Info, redefine, class, update)) {
2788 ResourceMark rm;
2789 if (!(*trace_name_printed)) {
2790 log_info(redefine, class, update)
2791 ("adjust: klassname=%s default methods from name=%s",
2792 external_name(), old_method->method_holder()->external_name());
2793 *trace_name_printed = true;
2794 }
2795 log_debug(redefine, class, update, vtables)
2796 ("default method update: %s(%s) ",
2797 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2798 }
2799 }
2800 }
2801 }
2802 #endif // INCLUDE_JVMTI
2803
2804 // On-stack replacement stuff
2805 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2806 // only one compilation can be active
2807 {
2808 // This is a short non-blocking critical region, so the no safepoint check is ok.
2809 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2810 assert(n->is_osr_method(), "wrong kind of nmethod");
2811 n->set_osr_link(osr_nmethods_head());
2812 set_osr_nmethods_head(n);
2813 // Raise the highest osr level if necessary
2814 if (TieredCompilation) {
2815 Method* m = n->method();
2816 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2817 }
2818 }
2819
2820 // Get rid of the osr methods for the same bci that have lower levels.
2821 if (TieredCompilation) {
2822 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2823 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2824 if (inv != NULL && inv->is_in_use()) {
2825 inv->make_not_entrant();
2826 }
2827 }
2828 }
2829 }
2830
2831 // Remove osr nmethod from the list. Return true if found and removed.
2832 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2833 // This is a short non-blocking critical region, so the no safepoint check is ok.
2834 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2835 assert(n->is_osr_method(), "wrong kind of nmethod");
2836 nmethod* last = NULL;
2837 nmethod* cur = osr_nmethods_head();
2838 int max_level = CompLevel_none; // Find the max comp level excluding n
2839 Method* m = n->method();
2840 // Search for match
2841 bool found = false;
2842 while(cur != NULL && cur != n) {
2843 if (TieredCompilation && m == cur->method()) {
2844 // Find max level before n
2845 max_level = MAX2(max_level, cur->comp_level());
2846 }
2847 last = cur;
2848 cur = cur->osr_link();
2849 }
2850 nmethod* next = NULL;
2851 if (cur == n) {
2852 found = true;
2853 next = cur->osr_link();
2854 if (last == NULL) {
2855 // Remove first element
2856 set_osr_nmethods_head(next);
2857 } else {
2858 last->set_osr_link(next);
2859 }
2860 }
2861 n->set_osr_link(NULL);
2862 if (TieredCompilation) {
2863 cur = next;
2864 while (cur != NULL) {
2865 // Find max level after n
2866 if (m == cur->method()) {
2867 max_level = MAX2(max_level, cur->comp_level());
2868 }
2869 cur = cur->osr_link();
2870 }
2871 m->set_highest_osr_comp_level(max_level);
2872 }
2873 return found;
2874 }
2875
2876 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2877 // This is a short non-blocking critical region, so the no safepoint check is ok.
2878 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2879 nmethod* osr = osr_nmethods_head();
2880 int found = 0;
2881 while (osr != NULL) {
2882 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2883 if (osr->method() == m) {
2884 osr->mark_for_deoptimization();
2885 found++;
2886 }
2887 osr = osr->osr_link();
2888 }
2889 return found;
2890 }
2891
2892 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2893 // This is a short non-blocking critical region, so the no safepoint check is ok.
2894 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2895 nmethod* osr = osr_nmethods_head();
2896 nmethod* best = NULL;
2897 while (osr != NULL) {
2898 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2899 // There can be a time when a c1 osr method exists but we are waiting
2900 // for a c2 version. When c2 completes its osr nmethod we will trash
2901 // the c1 version and only be able to find the c2 version. However
2902 // while we overflow in the c1 code at back branches we don't want to
2903 // try and switch to the same code as we are already running
2904
2905 if (osr->method() == m &&
2906 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2907 if (match_level) {
2908 if (osr->comp_level() == comp_level) {
2909 // Found a match - return it.
2910 return osr;
2911 }
2912 } else {
2913 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2914 if (osr->comp_level() == CompLevel_highest_tier) {
2915 // Found the best possible - return it.
2916 return osr;
2917 }
2918 best = osr;
2919 }
2920 }
2921 }
2922 osr = osr->osr_link();
2923 }
2924 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2925 return best;
2926 }
2927 return NULL;
2928 }
2929
2930 // -----------------------------------------------------------------------------------------------------
2931 // Printing
2932
2933 #ifndef PRODUCT
2934
2935 #define BULLET " - "
2936
2937 static const char* state_names[] = {
2938 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2939 };
2940
2941 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
2942 ResourceMark rm;
2943 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
2944 for (int i = 0; i < len; i++) forward_refs[i] = 0;
2945 for (int i = 0; i < len; i++) {
2946 intptr_t e = start[i];
2947 st->print("%d : " INTPTR_FORMAT, i, e);
2948 if (forward_refs[i] != 0) {
2949 int from = forward_refs[i];
2950 int off = (int) start[from];
2951 st->print(" (offset %d <= [%d])", off, from);
2952 }
2953 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2954 st->print(" ");
2955 ((Metadata*)e)->print_value_on(st);
2956 } else if (self != NULL && e > 0 && e < 0x10000) {
2957 address location = self + e;
2958 int index = (int)((intptr_t*)location - start);
2959 st->print(" (offset %d => [%d])", (int)e, index);
2960 if (index >= 0 && index < len)
2961 forward_refs[index] = i;
2962 }
2963 st->cr();
2964 }
2965 }
2966
2967 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2968 return print_vtable(NULL, reinterpret_cast<intptr_t*>(start), len, st);
2969 }
2970
2971 template<typename T>
2972 static void print_array_on(outputStream* st, Array<T>* array) {
2973 if (array == NULL) { st->print_cr("NULL"); return; }
2974 array->print_value_on(st); st->cr();
2975 if (Verbose || WizardMode) {
2976 for (int i = 0; i < array->length(); i++) {
2977 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
2978 }
2979 }
2980 }
2981
2982 static void print_array_on(outputStream* st, Array<int>* array) {
2983 if (array == NULL) { st->print_cr("NULL"); return; }
2984 array->print_value_on(st); st->cr();
2985 if (Verbose || WizardMode) {
2986 for (int i = 0; i < array->length(); i++) {
2987 st->print("%d : %d", i, array->at(i)); st->cr();
2988 }
2989 }
2990 }
2991
2992 void InstanceKlass::print_on(outputStream* st) const {
2993 assert(is_klass(), "must be klass");
2994 Klass::print_on(st);
2995
2996 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2997 st->print(BULLET"klass size: %d", size()); st->cr();
2998 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2999 st->print(BULLET"misc flags: 0x%x", _misc_flags); st->cr();
3000 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3001 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3002 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3003 st->print(BULLET"sub: ");
3004 Klass* sub = subklass();
3005 int n;
3006 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3007 if (n < MaxSubklassPrintSize) {
3008 sub->print_value_on(st);
3009 st->print(" ");
3010 }
3011 }
3012 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3013 st->cr();
3014
3015 if (is_interface()) {
3016 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3017 if (nof_implementors() == 1) {
3018 st->print_cr(BULLET"implementor: ");
3019 st->print(" ");
3020 implementor()->print_value_on(st);
3021 st->cr();
3022 }
3023 }
3024
3025 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3026 st->print(BULLET"methods: "); print_array_on(st, methods());
3027 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3028 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3029 if (default_vtable_indices() != NULL) {
3030 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3031 }
3032 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3033 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3034 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3035 if (class_loader_data() != NULL) {
3036 st->print(BULLET"class loader data: ");
3037 class_loader_data()->print_value_on(st);
3038 st->cr();
3039 }
3040 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3041 if (source_file_name() != NULL) {
3042 st->print(BULLET"source file: ");
3043 source_file_name()->print_value_on(st);
3044 st->cr();
3045 }
3046 if (source_debug_extension() != NULL) {
3047 st->print(BULLET"source debug extension: ");
3048 st->print("%s", source_debug_extension());
3049 st->cr();
3050 }
3051 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3052 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3053 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3054 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3055 {
3056 bool have_pv = false;
3057 // previous versions are linked together through the InstanceKlass
3058 for (InstanceKlass* pv_node = previous_versions();
3059 pv_node != NULL;
3060 pv_node = pv_node->previous_versions()) {
3061 if (!have_pv)
3062 st->print(BULLET"previous version: ");
3063 have_pv = true;
3064 pv_node->constants()->print_value_on(st);
3065 }
3066 if (have_pv) st->cr();
3067 }
3068
3069 if (generic_signature() != NULL) {
3070 st->print(BULLET"generic signature: ");
3071 generic_signature()->print_value_on(st);
3072 st->cr();
3073 }
3074 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3075 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3076 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3077 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3078 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3079 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(NULL, start_of_itable(), itable_length(), st);
3080 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3081 FieldPrinter print_static_field(st);
3082 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3083 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3084 FieldPrinter print_nonstatic_field(st);
3085 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3086 ik->do_nonstatic_fields(&print_nonstatic_field);
3087
3088 st->print(BULLET"non-static oop maps: ");
3089 OopMapBlock* map = start_of_nonstatic_oop_maps();
3090 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3091 while (map < end_map) {
3092 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3093 map++;
3094 }
3095 st->cr();
3096 }
3097
3098 #endif //PRODUCT
3099
3100 void InstanceKlass::print_value_on(outputStream* st) const {
3101 assert(is_klass(), "must be klass");
3102 if (Verbose || WizardMode) access_flags().print_on(st);
3103 name()->print_value_on(st);
3104 }
3105
3106 #ifndef PRODUCT
3107
3108 void FieldPrinter::do_field(fieldDescriptor* fd) {
3109 _st->print(BULLET);
3110 if (_obj == NULL) {
3111 fd->print_on(_st);
3112 _st->cr();
3113 } else {
3114 fd->print_on_for(_st, _obj);
3115 _st->cr();
3116 }
3117 }
3118
3119
3120 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3121 Klass::oop_print_on(obj, st);
3122
3123 if (this == SystemDictionary::String_klass()) {
3124 typeArrayOop value = java_lang_String::value(obj);
3125 juint length = java_lang_String::length(obj);
3126 if (value != NULL &&
3127 value->is_typeArray() &&
3128 length <= (juint) value->length()) {
3129 st->print(BULLET"string: ");
3130 java_lang_String::print(obj, st);
3131 st->cr();
3132 if (!WizardMode) return; // that is enough
3133 }
3134 }
3135
3136 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3137 FieldPrinter print_field(st, obj);
3138 do_nonstatic_fields(&print_field);
3139
3140 if (this == SystemDictionary::Class_klass()) {
3141 st->print(BULLET"signature: ");
3142 java_lang_Class::print_signature(obj, st);
3143 st->cr();
3144 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3145 st->print(BULLET"fake entry for mirror: ");
3146 mirrored_klass->print_value_on_maybe_null(st);
3147 st->cr();
3148 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3149 st->print(BULLET"fake entry for array: ");
3150 array_klass->print_value_on_maybe_null(st);
3151 st->cr();
3152 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3153 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3154 Klass* real_klass = java_lang_Class::as_Klass(obj);
3155 if (real_klass != NULL && real_klass->is_instance_klass()) {
3156 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3157 }
3158 } else if (this == SystemDictionary::MethodType_klass()) {
3159 st->print(BULLET"signature: ");
3160 java_lang_invoke_MethodType::print_signature(obj, st);
3161 st->cr();
3162 }
3163 }
3164
3165 #endif //PRODUCT
3166
3167 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3168 st->print("a ");
3169 name()->print_value_on(st);
3170 obj->print_address_on(st);
3171 if (this == SystemDictionary::String_klass()
3172 && java_lang_String::value(obj) != NULL) {
3173 ResourceMark rm;
3174 int len = java_lang_String::length(obj);
3175 int plen = (len < 24 ? len : 12);
3176 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3177 st->print(" = \"%s\"", str);
3178 if (len > plen)
3179 st->print("...[%d]", len);
3180 } else if (this == SystemDictionary::Class_klass()) {
3181 Klass* k = java_lang_Class::as_Klass(obj);
3182 st->print(" = ");
3183 if (k != NULL) {
3184 k->print_value_on(st);
3185 } else {
3186 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3187 st->print("%s", tname ? tname : "type?");
3188 }
3189 } else if (this == SystemDictionary::MethodType_klass()) {
3190 st->print(" = ");
3191 java_lang_invoke_MethodType::print_signature(obj, st);
3192 } else if (java_lang_boxing_object::is_instance(obj)) {
3193 st->print(" = ");
3194 java_lang_boxing_object::print(obj, st);
3195 } else if (this == SystemDictionary::LambdaForm_klass()) {
3196 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3197 if (vmentry != NULL) {
3198 st->print(" => ");
3199 vmentry->print_value_on(st);
3200 }
3201 } else if (this == SystemDictionary::MemberName_klass()) {
3202 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3203 if (vmtarget != NULL) {
3204 st->print(" = ");
3205 vmtarget->print_value_on(st);
3206 } else {
3207 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3208 st->print(".");
3209 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3210 }
3211 }
3212 }
3213
3214 const char* InstanceKlass::internal_name() const {
3215 return external_name();
3216 }
3217
3218 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3219 const char* module_name,
3220 const ClassFileStream* cfs) const {
3221 if (!log_is_enabled(Info, class, load)) {
3222 return;
3223 }
3224
3225 ResourceMark rm;
3226 LogMessage(class, load) msg;
3227 stringStream info_stream;
3228
3229 // Name and class hierarchy info
3230 info_stream.print("%s", external_name());
3231
3232 // Source
3233 if (cfs != NULL) {
3234 if (cfs->source() != NULL) {
3235 if (module_name != NULL) {
3236 if (ClassLoader::is_modules_image(cfs->source())) {
3237 info_stream.print(" source: jrt:/%s", module_name);
3238 } else {
3239 info_stream.print(" source: %s", cfs->source());
3240 }
3241 } else {
3242 info_stream.print(" source: %s", cfs->source());
3243 }
3244 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3245 Thread* THREAD = Thread::current();
3246 Klass* caller =
3247 THREAD->is_Java_thread()
3248 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3249 : NULL;
3250 // caller can be NULL, for example, during a JVMTI VM_Init hook
3251 if (caller != NULL) {
3252 info_stream.print(" source: instance of %s", caller->external_name());
3253 } else {
3254 // source is unknown
3255 }
3256 } else {
3257 oop class_loader = loader_data->class_loader();
3258 info_stream.print(" source: %s", class_loader->klass()->external_name());
3259 }
3260 } else {
3261 info_stream.print(" source: shared objects file");
3262 }
3263
3264 msg.info("%s", info_stream.as_string());
3265
3266 if (log_is_enabled(Debug, class, load)) {
3267 stringStream debug_stream;
3268
3269 // Class hierarchy info
3270 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3271 p2i(this), p2i(superklass()));
3272
3273 // Interfaces
3274 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3275 debug_stream.print(" interfaces:");
3276 int length = local_interfaces()->length();
3277 for (int i = 0; i < length; i++) {
3278 debug_stream.print(" " INTPTR_FORMAT,
3279 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3280 }
3281 }
3282
3283 // Class loader
3284 debug_stream.print(" loader: [");
3285 loader_data->print_value_on(&debug_stream);
3286 debug_stream.print("]");
3287
3288 // Classfile checksum
3289 if (cfs) {
3290 debug_stream.print(" bytes: %d checksum: %08x",
3291 cfs->length(),
3292 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3293 cfs->length()));
3294 }
3295
3296 msg.debug("%s", debug_stream.as_string());
3297 }
3298 }
3299
3300 #if INCLUDE_SERVICES
3301 // Size Statistics
3302 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3303 Klass::collect_statistics(sz);
3304
3305 sz->_inst_size = wordSize * size_helper();
3306 sz->_vtab_bytes = wordSize * vtable_length();
3307 sz->_itab_bytes = wordSize * itable_length();
3308 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3309
3310 int n = 0;
3311 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3312 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3313 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3314 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3315 n += (sz->_fields_bytes = sz->count_array(fields()));
3316 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3317 sz->_ro_bytes += n;
3318
3319 const ConstantPool* cp = constants();
3320 if (cp) {
3321 cp->collect_statistics(sz);
3322 }
3323
3324 const Annotations* anno = annotations();
3325 if (anno) {
3326 anno->collect_statistics(sz);
3327 }
3328
3329 const Array<Method*>* methods_array = methods();
3330 if (methods()) {
3331 for (int i = 0; i < methods_array->length(); i++) {
3332 Method* method = methods_array->at(i);
3333 if (method) {
3334 sz->_method_count ++;
3335 method->collect_statistics(sz);
3336 }
3337 }
3338 }
3339 }
3340 #endif // INCLUDE_SERVICES
3341
3342 // Verification
3343
3344 class VerifyFieldClosure: public OopClosure {
3345 protected:
3346 template <class T> void do_oop_work(T* p) {
3347 oop obj = oopDesc::load_decode_heap_oop(p);
3348 if (!oopDesc::is_oop_or_null(obj)) {
3349 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3350 Universe::print_on(tty);
3351 guarantee(false, "boom");
3352 }
3353 }
3354 public:
3355 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3356 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3357 };
3358
3359 void InstanceKlass::verify_on(outputStream* st) {
3360 #ifndef PRODUCT
3361 // Avoid redundant verifies, this really should be in product.
3362 if (_verify_count == Universe::verify_count()) return;
3363 _verify_count = Universe::verify_count();
3364 #endif
3365
3366 // Verify Klass
3367 Klass::verify_on(st);
3368
3369 // Verify that klass is present in ClassLoaderData
3370 guarantee(class_loader_data()->contains_klass(this),
3371 "this class isn't found in class loader data");
3372
3373 // Verify vtables
3374 if (is_linked()) {
3375 // $$$ This used to be done only for m/s collections. Doing it
3376 // always seemed a valid generalization. (DLD -- 6/00)
3377 vtable().verify(st);
3378 }
3379
3380 // Verify first subklass
3381 if (subklass() != NULL) {
3382 guarantee(subklass()->is_klass(), "should be klass");
3383 }
3384
3385 // Verify siblings
3386 Klass* super = this->super();
3387 Klass* sib = next_sibling();
3388 if (sib != NULL) {
3389 if (sib == this) {
3390 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3391 }
3392
3393 guarantee(sib->is_klass(), "should be klass");
3394 guarantee(sib->super() == super, "siblings should have same superklass");
3395 }
3396
3397 // Verify implementor fields
3398 Klass* im = implementor();
3399 if (im != NULL) {
3400 guarantee(is_interface(), "only interfaces should have implementor set");
3401 guarantee(im->is_klass(), "should be klass");
3402 guarantee(!im->is_interface() || im == this,
3403 "implementors cannot be interfaces");
3404 }
3405
3406 // Verify local interfaces
3407 if (local_interfaces()) {
3408 Array<Klass*>* local_interfaces = this->local_interfaces();
3409 for (int j = 0; j < local_interfaces->length(); j++) {
3410 Klass* e = local_interfaces->at(j);
3411 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3412 }
3413 }
3414
3415 // Verify transitive interfaces
3416 if (transitive_interfaces() != NULL) {
3417 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3418 for (int j = 0; j < transitive_interfaces->length(); j++) {
3419 Klass* e = transitive_interfaces->at(j);
3420 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3421 }
3422 }
3423
3424 // Verify methods
3425 if (methods() != NULL) {
3426 Array<Method*>* methods = this->methods();
3427 for (int j = 0; j < methods->length(); j++) {
3428 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3429 }
3430 for (int j = 0; j < methods->length() - 1; j++) {
3431 Method* m1 = methods->at(j);
3432 Method* m2 = methods->at(j + 1);
3433 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3434 }
3435 }
3436
3437 // Verify method ordering
3438 if (method_ordering() != NULL) {
3439 Array<int>* method_ordering = this->method_ordering();
3440 int length = method_ordering->length();
3441 if (JvmtiExport::can_maintain_original_method_order() ||
3442 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3443 guarantee(length == methods()->length(), "invalid method ordering length");
3444 jlong sum = 0;
3445 for (int j = 0; j < length; j++) {
3446 int original_index = method_ordering->at(j);
3447 guarantee(original_index >= 0, "invalid method ordering index");
3448 guarantee(original_index < length, "invalid method ordering index");
3449 sum += original_index;
3450 }
3451 // Verify sum of indices 0,1,...,length-1
3452 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3453 } else {
3454 guarantee(length == 0, "invalid method ordering length");
3455 }
3456 }
3457
3458 // Verify default methods
3459 if (default_methods() != NULL) {
3460 Array<Method*>* methods = this->default_methods();
3461 for (int j = 0; j < methods->length(); j++) {
3462 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3463 }
3464 for (int j = 0; j < methods->length() - 1; j++) {
3465 Method* m1 = methods->at(j);
3466 Method* m2 = methods->at(j + 1);
3467 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3468 }
3469 }
3470
3471 // Verify JNI static field identifiers
3472 if (jni_ids() != NULL) {
3473 jni_ids()->verify(this);
3474 }
3475
3476 // Verify other fields
3477 if (array_klasses() != NULL) {
3478 guarantee(array_klasses()->is_klass(), "should be klass");
3479 }
3480 if (constants() != NULL) {
3481 guarantee(constants()->is_constantPool(), "should be constant pool");
3482 }
3483 const Klass* host = host_klass();
3484 if (host != NULL) {
3485 guarantee(host->is_klass(), "should be klass");
3486 }
3487 }
3488
3489 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3490 Klass::oop_verify_on(obj, st);
3491 VerifyFieldClosure blk;
3492 obj->oop_iterate_no_header(&blk);
3493 }
3494
3495
3496 // JNIid class for jfieldIDs only
3497 // Note to reviewers:
3498 // These JNI functions are just moved over to column 1 and not changed
3499 // in the compressed oops workspace.
3500 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3501 _holder = holder;
3502 _offset = offset;
3503 _next = next;
3504 debug_only(_is_static_field_id = false;)
3505 }
3506
3507
3508 JNIid* JNIid::find(int offset) {
3509 JNIid* current = this;
3510 while (current != NULL) {
3511 if (current->offset() == offset) return current;
3512 current = current->next();
3513 }
3514 return NULL;
3515 }
3516
3517 void JNIid::deallocate(JNIid* current) {
3518 while (current != NULL) {
3519 JNIid* next = current->next();
3520 delete current;
3521 current = next;
3522 }
3523 }
3524
3525
3526 void JNIid::verify(Klass* holder) {
3527 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3528 int end_field_offset;
3529 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3530
3531 JNIid* current = this;
3532 while (current != NULL) {
3533 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3534 #ifdef ASSERT
3535 int o = current->offset();
3536 if (current->is_static_field_id()) {
3537 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3538 }
3539 #endif
3540 current = current->next();
3541 }
3542 }
3543
3544 oop InstanceKlass::klass_holder_phantom() {
3545 oop* addr;
3546 if (is_anonymous()) {
3547 addr = _java_mirror.ptr_raw();
3548 } else {
3549 addr = &class_loader_data()->_class_loader;
3550 }
3551 return RootAccess<IN_CONCURRENT_ROOT | ON_PHANTOM_OOP_REF>::oop_load(addr);
3552 }
3553
3554 #ifdef ASSERT
3555 void InstanceKlass::set_init_state(ClassState state) {
3556 bool good_state = is_shared() ? (_init_state <= state)
3557 : (_init_state < state);
3558 assert(good_state || state == allocated, "illegal state transition");
3559 _init_state = (u1)state;
3560 }
3561 #endif
3562
3563 #if INCLUDE_JVMTI
3564
3565 // RedefineClasses() support for previous versions
3566
3567 // Globally, there is at least one previous version of a class to walk
3568 // during class unloading, which is saved because old methods in the class
3569 // are still running. Otherwise the previous version list is cleaned up.
3570 bool InstanceKlass::_has_previous_versions = false;
3571
3572 // Returns true if there are previous versions of a class for class
3573 // unloading only. Also resets the flag to false. purge_previous_version
3574 // will set the flag to true if there are any left, i.e., if there's any
3575 // work to do for next time. This is to avoid the expensive code cache
3576 // walk in CLDG::do_unloading().
3577 bool InstanceKlass::has_previous_versions_and_reset() {
3578 bool ret = _has_previous_versions;
3579 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3580 ret ? "true" : "false");
3581 _has_previous_versions = false;
3582 return ret;
3583 }
3584
3585 // Purge previous versions before adding new previous versions of the class and
3586 // during class unloading.
3587 void InstanceKlass::purge_previous_version_list() {
3588 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3589 assert(has_been_redefined(), "Should only be called for main class");
3590
3591 // Quick exit.
3592 if (previous_versions() == NULL) {
3593 return;
3594 }
3595
3596 // This klass has previous versions so see what we can cleanup
3597 // while it is safe to do so.
3598
3599 int deleted_count = 0; // leave debugging breadcrumbs
3600 int live_count = 0;
3601 ClassLoaderData* loader_data = class_loader_data();
3602 assert(loader_data != NULL, "should never be null");
3603
3604 ResourceMark rm;
3605 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3606
3607 // previous versions are linked together through the InstanceKlass
3608 InstanceKlass* pv_node = previous_versions();
3609 InstanceKlass* last = this;
3610 int version = 0;
3611
3612 // check the previous versions list
3613 for (; pv_node != NULL; ) {
3614
3615 ConstantPool* pvcp = pv_node->constants();
3616 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3617
3618 if (!pvcp->on_stack()) {
3619 // If the constant pool isn't on stack, none of the methods
3620 // are executing. Unlink this previous_version.
3621 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3622 // so will be deallocated during the next phase of class unloading.
3623 log_trace(redefine, class, iklass, purge)
3624 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3625 // For debugging purposes.
3626 pv_node->set_is_scratch_class();
3627 // Unlink from previous version list.
3628 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3629 InstanceKlass* next = pv_node->previous_versions();
3630 pv_node->link_previous_versions(NULL); // point next to NULL
3631 last->link_previous_versions(next);
3632 // Add to the deallocate list after unlinking
3633 loader_data->add_to_deallocate_list(pv_node);
3634 pv_node = next;
3635 deleted_count++;
3636 version++;
3637 continue;
3638 } else {
3639 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3640 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3641 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3642 live_count++;
3643 // found a previous version for next time we do class unloading
3644 _has_previous_versions = true;
3645 }
3646
3647 // At least one method is live in this previous version.
3648 // Reset dead EMCP methods not to get breakpoints.
3649 // All methods are deallocated when all of the methods for this class are no
3650 // longer running.
3651 Array<Method*>* method_refs = pv_node->methods();
3652 if (method_refs != NULL) {
3653 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3654 for (int j = 0; j < method_refs->length(); j++) {
3655 Method* method = method_refs->at(j);
3656
3657 if (!method->on_stack()) {
3658 // no breakpoints for non-running methods
3659 if (method->is_running_emcp()) {
3660 method->set_running_emcp(false);
3661 }
3662 } else {
3663 assert (method->is_obsolete() || method->is_running_emcp(),
3664 "emcp method cannot run after emcp bit is cleared");
3665 log_trace(redefine, class, iklass, purge)
3666 ("purge: %s(%s): prev method @%d in version @%d is alive",
3667 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3668 }
3669 }
3670 }
3671 // next previous version
3672 last = pv_node;
3673 pv_node = pv_node->previous_versions();
3674 version++;
3675 }
3676 log_trace(redefine, class, iklass, purge)
3677 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3678 }
3679
3680 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3681 int emcp_method_count) {
3682 int obsolete_method_count = old_methods->length() - emcp_method_count;
3683
3684 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3685 _previous_versions != NULL) {
3686 // We have a mix of obsolete and EMCP methods so we have to
3687 // clear out any matching EMCP method entries the hard way.
3688 int local_count = 0;
3689 for (int i = 0; i < old_methods->length(); i++) {
3690 Method* old_method = old_methods->at(i);
3691 if (old_method->is_obsolete()) {
3692 // only obsolete methods are interesting
3693 Symbol* m_name = old_method->name();
3694 Symbol* m_signature = old_method->signature();
3695
3696 // previous versions are linked together through the InstanceKlass
3697 int j = 0;
3698 for (InstanceKlass* prev_version = _previous_versions;
3699 prev_version != NULL;
3700 prev_version = prev_version->previous_versions(), j++) {
3701
3702 Array<Method*>* method_refs = prev_version->methods();
3703 for (int k = 0; k < method_refs->length(); k++) {
3704 Method* method = method_refs->at(k);
3705
3706 if (!method->is_obsolete() &&
3707 method->name() == m_name &&
3708 method->signature() == m_signature) {
3709 // The current RedefineClasses() call has made all EMCP
3710 // versions of this method obsolete so mark it as obsolete
3711 log_trace(redefine, class, iklass, add)
3712 ("%s(%s): flush obsolete method @%d in version @%d",
3713 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3714
3715 method->set_is_obsolete();
3716 break;
3717 }
3718 }
3719
3720 // The previous loop may not find a matching EMCP method, but
3721 // that doesn't mean that we can optimize and not go any
3722 // further back in the PreviousVersion generations. The EMCP
3723 // method for this generation could have already been made obsolete,
3724 // but there still may be an older EMCP method that has not
3725 // been made obsolete.
3726 }
3727
3728 if (++local_count >= obsolete_method_count) {
3729 // no more obsolete methods so bail out now
3730 break;
3731 }
3732 }
3733 }
3734 }
3735 }
3736
3737 // Save the scratch_class as the previous version if any of the methods are running.
3738 // The previous_versions are used to set breakpoints in EMCP methods and they are
3739 // also used to clean MethodData links to redefined methods that are no longer running.
3740 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3741 int emcp_method_count) {
3742 assert(Thread::current()->is_VM_thread(),
3743 "only VMThread can add previous versions");
3744
3745 ResourceMark rm;
3746 log_trace(redefine, class, iklass, add)
3747 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3748
3749 // Clean out old previous versions for this class
3750 purge_previous_version_list();
3751
3752 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3753 // a previous redefinition may be made obsolete by this redefinition.
3754 Array<Method*>* old_methods = scratch_class->methods();
3755 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3756
3757 // If the constant pool for this previous version of the class
3758 // is not marked as being on the stack, then none of the methods
3759 // in this previous version of the class are on the stack so
3760 // we don't need to add this as a previous version.
3761 ConstantPool* cp_ref = scratch_class->constants();
3762 if (!cp_ref->on_stack()) {
3763 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3764 // For debugging purposes.
3765 scratch_class->set_is_scratch_class();
3766 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3767 return;
3768 }
3769
3770 if (emcp_method_count != 0) {
3771 // At least one method is still running, check for EMCP methods
3772 for (int i = 0; i < old_methods->length(); i++) {
3773 Method* old_method = old_methods->at(i);
3774 if (!old_method->is_obsolete() && old_method->on_stack()) {
3775 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3776 // we can add breakpoints for it.
3777
3778 // We set the method->on_stack bit during safepoints for class redefinition
3779 // and use this bit to set the is_running_emcp bit.
3780 // After the safepoint, the on_stack bit is cleared and the running emcp
3781 // method may exit. If so, we would set a breakpoint in a method that
3782 // is never reached, but this won't be noticeable to the programmer.
3783 old_method->set_running_emcp(true);
3784 log_trace(redefine, class, iklass, add)
3785 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3786 } else if (!old_method->is_obsolete()) {
3787 log_trace(redefine, class, iklass, add)
3788 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3789 }
3790 }
3791 }
3792
3793 // Add previous version if any methods are still running.
3794 // Set has_previous_version flag for processing during class unloading.
3795 _has_previous_versions = true;
3796 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3797 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3798 scratch_class->link_previous_versions(previous_versions());
3799 link_previous_versions(scratch_class);
3800 } // end add_previous_version()
3801
3802 #endif // INCLUDE_JVMTI
3803
3804 Method* InstanceKlass::method_with_idnum(int idnum) {
3805 Method* m = NULL;
3806 if (idnum < methods()->length()) {
3807 m = methods()->at(idnum);
3808 }
3809 if (m == NULL || m->method_idnum() != idnum) {
3810 for (int index = 0; index < methods()->length(); ++index) {
3811 m = methods()->at(index);
3812 if (m->method_idnum() == idnum) {
3813 return m;
3814 }
3815 }
3816 // None found, return null for the caller to handle.
3817 return NULL;
3818 }
3819 return m;
3820 }
3821
3822
3823 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3824 if (idnum >= methods()->length()) {
3825 return NULL;
3826 }
3827 Method* m = methods()->at(idnum);
3828 if (m != NULL && m->orig_method_idnum() == idnum) {
3829 return m;
3830 }
3831 // Obsolete method idnum does not match the original idnum
3832 for (int index = 0; index < methods()->length(); ++index) {
3833 m = methods()->at(index);
3834 if (m->orig_method_idnum() == idnum) {
3835 return m;
3836 }
3837 }
3838 // None found, return null for the caller to handle.
3839 return NULL;
3840 }
3841
3842
3843 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3844 InstanceKlass* holder = get_klass_version(version);
3845 if (holder == NULL) {
3846 return NULL; // The version of klass is gone, no method is found
3847 }
3848 Method* method = holder->method_with_orig_idnum(idnum);
3849 return method;
3850 }
3851
3852 #if INCLUDE_JVMTI
3853 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3854 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3855 // Ignore the archived class stream data
3856 return NULL;
3857 } else {
3858 return _cached_class_file;
3859 }
3860 }
3861
3862 jint InstanceKlass::get_cached_class_file_len() {
3863 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3864 }
3865
3866 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3867 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3868 }
3869
3870 #if INCLUDE_CDS
3871 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3872 if (DumpSharedSpaces) {
3873 return _cached_class_file;
3874 } else {
3875 assert(this->is_shared(), "class should be shared");
3876 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3877 return _cached_class_file;
3878 } else {
3879 return NULL;
3880 }
3881 }
3882 }
3883 #endif
3884 #endif
3885
3886 #define THROW_DVT_ERROR(s) \
3887 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), \
3888 "ValueCapableClass class '%s' %s", external_name(),(s)); \
3889 return