1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/javaClasses.hpp"
32 #include "classfile/moduleEntry.hpp"
33 #include "classfile/systemDictionary.hpp"
34 #include "classfile/systemDictionaryShared.hpp"
35 #include "classfile/verifier.hpp"
36 #include "classfile/vmSymbols.hpp"
37 #include "code/dependencyContext.hpp"
38 #include "compiler/compileBroker.hpp"
39 #include "gc/shared/collectedHeap.inline.hpp"
40 #include "gc/shared/specialized_oop_closures.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "interpreter/rewriter.hpp"
43 #include "jvmtifiles/jvmti.h"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/heapInspection.hpp"
48 #include "memory/iterator.inline.hpp"
49 #include "memory/metadataFactory.hpp"
50 #include "memory/metaspaceClosure.hpp"
51 #include "memory/metaspaceShared.hpp"
52 #include "memory/oopFactory.hpp"
53 #include "memory/resourceArea.hpp"
54 #include "oops/fieldStreams.hpp"
55 #include "oops/instanceClassLoaderKlass.hpp"
56 #include "oops/instanceKlass.inline.hpp"
57 #include "oops/instanceMirrorKlass.hpp"
58 #include "oops/instanceOop.hpp"
59 #include "oops/klass.inline.hpp"
60 #include "oops/method.hpp"
61 #include "oops/oop.inline.hpp"
62 #include "oops/symbol.hpp"
63 #include "oops/valueKlass.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "prims/jvmtiRedefineClasses.hpp"
66 #include "prims/jvmtiThreadState.hpp"
67 #include "prims/methodComparator.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/fieldDescriptor.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/javaCalls.hpp"
72 #include "runtime/mutexLocker.hpp"
73 #include "runtime/orderAccess.inline.hpp"
74 #include "runtime/thread.inline.hpp"
75 #include "services/classLoadingService.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/dtrace.hpp"
78 #include "utilities/macros.hpp"
79 #include "utilities/stringUtils.hpp"
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83
84 #ifdef DTRACE_ENABLED
85
86
87 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
88 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
89 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
90 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
91 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
92 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
93 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
94 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
95 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
96 { \
97 char* data = NULL; \
98 int len = 0; \
99 Symbol* clss_name = name(); \
100 if (clss_name != NULL) { \
101 data = (char*)clss_name->bytes(); \
102 len = clss_name->utf8_length(); \
103 } \
104 HOTSPOT_CLASS_INITIALIZATION_##type( \
105 data, len, (void*)class_loader(), thread_type); \
106 }
107
108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
109 { \
110 char* data = NULL; \
111 int len = 0; \
112 Symbol* clss_name = name(); \
113 if (clss_name != NULL) { \
114 data = (char*)clss_name->bytes(); \
115 len = clss_name->utf8_length(); \
116 } \
117 HOTSPOT_CLASS_INITIALIZATION_##type( \
118 data, len, (void*)class_loader(), thread_type, wait); \
119 }
120
121 #else // ndef DTRACE_ENABLED
122
123 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
125
126 #endif // ndef DTRACE_ENABLED
127
128 static inline bool is_class_loader(const Symbol* class_name,
129 const ClassFileParser& parser) {
130 assert(class_name != NULL, "invariant");
131
132 if (class_name == vmSymbols::java_lang_ClassLoader()) {
133 return true;
134 }
135
136 if (SystemDictionary::ClassLoader_klass_loaded()) {
137 const Klass* const super_klass = parser.super_klass();
138 if (super_klass != NULL) {
139 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
140 return true;
141 }
142 }
143 }
144 return false;
145 }
146
147 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
148 const int size = InstanceKlass::size(parser.vtable_size(),
149 parser.itable_size(),
150 nonstatic_oop_map_size(parser.total_oop_map_count()),
151 parser.is_interface(),
152 parser.is_anonymous(),
153 should_store_fingerprint(parser.is_anonymous()),
154 parser.has_flattenable_fields() ? parser.java_fields_count() : 0,
155 parser.is_value_type());
156
157 const Symbol* const class_name = parser.class_name();
158 assert(class_name != NULL, "invariant");
159 ClassLoaderData* loader_data = parser.loader_data();
160 assert(loader_data != NULL, "invariant");
161
162 InstanceKlass* ik;
163
164 // Allocation
165 if (REF_NONE == parser.reference_type()) {
166 if (class_name == vmSymbols::java_lang_Class()) {
167 // mirror
168 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
169 } else if (is_class_loader(class_name, parser)) {
170 // class loader
171 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
172 } else if (parser.is_value_type()) {
173 // value type
174 ik = new (loader_data, size, THREAD) ValueKlass(parser);
175 } else {
176 // normal
177 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
178 }
179 } else {
180 // reference
181 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
182 }
183
184 // Check for pending exception before adding to the loader data and incrementing
185 // class count. Can get OOM here.
186 if (HAS_PENDING_EXCEPTION) {
187 return NULL;
188 }
189
190 assert(ik != NULL, "invariant");
191
192 const bool publicize = !parser.is_internal();
193 #ifdef ASSERT
194 assert(ik->size() == size, "");
195 ik->bounds_check((address) ik->start_of_vtable(), false, size);
196 ik->bounds_check((address) ik->start_of_itable(), false, size);
197 ik->bounds_check((address) ik->end_of_itable(), true, size);
198 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
199 #endif //ASSERT
200
201 // Add all classes to our internal class loader list here,
202 // including classes in the bootstrap (NULL) class loader.
203 loader_data->add_class(ik, publicize);
204 return ik;
205 }
206
207 #ifndef PRODUCT
208 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
209 const char* bad = NULL;
210 address end = NULL;
211 if (addr < (address)this) {
212 bad = "before";
213 } else if (addr == (address)this) {
214 if (edge_ok) return true;
215 bad = "just before";
216 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
217 if (edge_ok) return true;
218 bad = "just after";
219 } else if (addr > end) {
220 bad = "after";
221 } else {
222 return true;
223 }
224 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
225 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
226 Verbose = WizardMode = true; this->print(); //@@
227 return false;
228 }
229 #endif //PRODUCT
230
231 // copy method ordering from resource area to Metaspace
232 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
233 if (m != NULL) {
234 // allocate a new array and copy contents (memcpy?)
235 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
236 for (int i = 0; i < m->length(); i++) {
237 _method_ordering->at_put(i, m->at(i));
238 }
239 } else {
240 _method_ordering = Universe::the_empty_int_array();
241 }
242 }
243
244 // create a new array of vtable_indices for default methods
245 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
246 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
247 assert(default_vtable_indices() == NULL, "only create once");
248 set_default_vtable_indices(vtable_indices);
249 return vtable_indices;
250 }
251
252 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
253 _static_field_size(parser.static_field_size()),
254 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
255 _itable_len(parser.itable_size()),
256 _reference_type(parser.reference_type()),
257 _extra_flags(0),
258 _adr_valueklass_fixed_block(NULL) {
259 set_vtable_length(parser.vtable_size());
260 set_kind(kind);
261 set_access_flags(parser.access_flags());
262 set_is_anonymous(parser.is_anonymous());
263 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
264 false));
265 if (parser.has_flattenable_fields()) {
266 set_has_value_fields();
267 }
268 _java_fields_count = parser.java_fields_count();
269
270 assert(NULL == _methods, "underlying memory not zeroed?");
271 assert(is_instance_klass(), "is layout incorrect?");
272 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
273 }
274
275 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
276 Array<Method*>* methods) {
277 if (methods != NULL && methods != Universe::the_empty_method_array() &&
278 !methods->is_shared()) {
279 for (int i = 0; i < methods->length(); i++) {
280 Method* method = methods->at(i);
281 if (method == NULL) continue; // maybe null if error processing
282 // Only want to delete methods that are not executing for RedefineClasses.
283 // The previous version will point to them so they're not totally dangling
284 assert (!method->on_stack(), "shouldn't be called with methods on stack");
285 MetadataFactory::free_metadata(loader_data, method);
286 }
287 MetadataFactory::free_array<Method*>(loader_data, methods);
288 }
289 }
290
291 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
292 const Klass* super_klass,
293 Array<Klass*>* local_interfaces,
294 Array<Klass*>* transitive_interfaces) {
295 // Only deallocate transitive interfaces if not empty, same as super class
296 // or same as local interfaces. See code in parseClassFile.
297 Array<Klass*>* ti = transitive_interfaces;
298 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
299 // check that the interfaces don't come from super class
300 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
301 InstanceKlass::cast(super_klass)->transitive_interfaces();
302 if (ti != sti && ti != NULL && !ti->is_shared()) {
303 MetadataFactory::free_array<Klass*>(loader_data, ti);
304 }
305 }
306
307 // local interfaces can be empty
308 if (local_interfaces != Universe::the_empty_klass_array() &&
309 local_interfaces != NULL && !local_interfaces->is_shared()) {
310 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
311 }
312 }
313
314 // This function deallocates the metadata and C heap pointers that the
315 // InstanceKlass points to.
316 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
317
318 // Orphan the mirror first, CMS thinks it's still live.
319 if (java_mirror() != NULL) {
320 java_lang_Class::set_klass(java_mirror(), NULL);
321 }
322
323 // Also remove mirror from handles
324 loader_data->remove_handle(_java_mirror);
325
326 // Need to take this class off the class loader data list.
327 loader_data->remove_class(this);
328
329 // The array_klass for this class is created later, after error handling.
330 // For class redefinition, we keep the original class so this scratch class
331 // doesn't have an array class. Either way, assert that there is nothing
332 // to deallocate.
333 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
334
335 // Release C heap allocated data that this might point to, which includes
336 // reference counting symbol names.
337 release_C_heap_structures();
338
339 deallocate_methods(loader_data, methods());
340 set_methods(NULL);
341
342 if (method_ordering() != NULL &&
343 method_ordering() != Universe::the_empty_int_array() &&
344 !method_ordering()->is_shared()) {
345 MetadataFactory::free_array<int>(loader_data, method_ordering());
346 }
347 set_method_ordering(NULL);
348
349 // default methods can be empty
350 if (default_methods() != NULL &&
351 default_methods() != Universe::the_empty_method_array() &&
352 !default_methods()->is_shared()) {
353 MetadataFactory::free_array<Method*>(loader_data, default_methods());
354 }
355 // Do NOT deallocate the default methods, they are owned by superinterfaces.
356 set_default_methods(NULL);
357
358 // default methods vtable indices can be empty
359 if (default_vtable_indices() != NULL &&
360 !default_vtable_indices()->is_shared()) {
361 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
362 }
363 set_default_vtable_indices(NULL);
364
365
366 // This array is in Klass, but remove it with the InstanceKlass since
367 // this place would be the only caller and it can share memory with transitive
368 // interfaces.
369 if (secondary_supers() != NULL &&
370 secondary_supers() != Universe::the_empty_klass_array() &&
371 secondary_supers() != transitive_interfaces() &&
372 !secondary_supers()->is_shared()) {
373 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
374 }
375 set_secondary_supers(NULL);
376
377 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
378 set_transitive_interfaces(NULL);
379 set_local_interfaces(NULL);
380
381 if (fields() != NULL && !fields()->is_shared()) {
382 MetadataFactory::free_array<jushort>(loader_data, fields());
383 }
384 set_fields(NULL, 0);
385
386 // If a method from a redefined class is using this constant pool, don't
387 // delete it, yet. The new class's previous version will point to this.
388 if (constants() != NULL) {
389 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
390 if (!constants()->is_shared()) {
391 MetadataFactory::free_metadata(loader_data, constants());
392 }
393 // Delete any cached resolution errors for the constant pool
394 SystemDictionary::delete_resolution_error(constants());
395
396 set_constants(NULL);
397 }
398
399 if (inner_classes() != NULL &&
400 inner_classes() != Universe::the_empty_short_array() &&
401 !inner_classes()->is_shared()) {
402 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
403 }
404 set_inner_classes(NULL);
405
406 if (value_types() != NULL && !value_types()->is_shared()) {
407 MetadataFactory::free_array<ValueTypes>(loader_data, value_types());
408 }
409 set_value_types(NULL);
410
411 // We should deallocate the Annotations instance if it's not in shared spaces.
412 if (annotations() != NULL && !annotations()->is_shared()) {
413 MetadataFactory::free_metadata(loader_data, annotations());
414 }
415 set_annotations(NULL);
416 }
417
418 bool InstanceKlass::should_be_initialized() const {
419 return !is_initialized();
420 }
421
422 klassItable InstanceKlass::itable() const {
423 return klassItable(const_cast<InstanceKlass*>(this));
424 }
425
426 void InstanceKlass::eager_initialize(Thread *thread) {
427 if (!EagerInitialization) return;
428
429 if (this->is_not_initialized()) {
430 // abort if the the class has a class initializer
431 if (this->class_initializer() != NULL) return;
432
433 // abort if it is java.lang.Object (initialization is handled in genesis)
434 Klass* super_klass = super();
435 if (super_klass == NULL) return;
436
437 // abort if the super class should be initialized
438 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
439
440 // call body to expose the this pointer
441 eager_initialize_impl();
442 }
443 }
444
445 // JVMTI spec thinks there are signers and protection domain in the
446 // instanceKlass. These accessors pretend these fields are there.
447 // The hprof specification also thinks these fields are in InstanceKlass.
448 oop InstanceKlass::protection_domain() const {
449 // return the protection_domain from the mirror
450 return java_lang_Class::protection_domain(java_mirror());
451 }
452
453 // To remove these from requires an incompatible change and CCC request.
454 objArrayOop InstanceKlass::signers() const {
455 // return the signers from the mirror
456 return java_lang_Class::signers(java_mirror());
457 }
458
459 oop InstanceKlass::init_lock() const {
460 // return the init lock from the mirror
461 oop lock = java_lang_Class::init_lock(java_mirror());
462 // Prevent reordering with any access of initialization state
463 OrderAccess::loadload();
464 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
465 "only fully initialized state can have a null lock");
466 return lock;
467 }
468
469 // Set the initialization lock to null so the object can be GC'ed. Any racing
470 // threads to get this lock will see a null lock and will not lock.
471 // That's okay because they all check for initialized state after getting
472 // the lock and return.
473 void InstanceKlass::fence_and_clear_init_lock() {
474 // make sure previous stores are all done, notably the init_state.
475 OrderAccess::storestore();
476 java_lang_Class::set_init_lock(java_mirror(), NULL);
477 assert(!is_not_initialized(), "class must be initialized now");
478 }
479
480 void InstanceKlass::eager_initialize_impl() {
481 EXCEPTION_MARK;
482 HandleMark hm(THREAD);
483 Handle h_init_lock(THREAD, init_lock());
484 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
485
486 // abort if someone beat us to the initialization
487 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
488
489 ClassState old_state = init_state();
490 link_class_impl(true, THREAD);
491 if (HAS_PENDING_EXCEPTION) {
492 CLEAR_PENDING_EXCEPTION;
493 // Abort if linking the class throws an exception.
494
495 // Use a test to avoid redundantly resetting the state if there's
496 // no change. Set_init_state() asserts that state changes make
497 // progress, whereas here we might just be spinning in place.
498 if (old_state != _init_state)
499 set_init_state(old_state);
500 } else {
501 // linking successfull, mark class as initialized
502 set_init_state(fully_initialized);
503 fence_and_clear_init_lock();
504 // trace
505 if (log_is_enabled(Info, class, init)) {
506 ResourceMark rm(THREAD);
507 log_info(class, init)("[Initialized %s without side effects]", external_name());
508 }
509 }
510 }
511
512
513 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
514 // process. The step comments refers to the procedure described in that section.
515 // Note: implementation moved to static method to expose the this pointer.
516 void InstanceKlass::initialize(TRAPS) {
517 if (this->should_be_initialized()) {
518 initialize_impl(CHECK);
519 // Note: at this point the class may be initialized
520 // OR it may be in the state of being initialized
521 // in case of recursive initialization!
522 } else {
523 assert(is_initialized(), "sanity check");
524 }
525 }
526
527
528 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
529 // 1) Verify the bytecodes
530 Verifier::Mode mode =
531 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
532 return Verifier::verify(this, mode, should_verify_class(), THREAD);
533 }
534
535
536 // Used exclusively by the shared spaces dump mechanism to prevent
537 // classes mapped into the shared regions in new VMs from appearing linked.
538
539 void InstanceKlass::unlink_class() {
540 assert(is_linked(), "must be linked");
541 _init_state = loaded;
542 }
543
544 void InstanceKlass::link_class(TRAPS) {
545 assert(is_loaded(), "must be loaded");
546 if (!is_linked()) {
547 link_class_impl(true, CHECK);
548 }
549 }
550
551 // Called to verify that a class can link during initialization, without
552 // throwing a VerifyError.
553 bool InstanceKlass::link_class_or_fail(TRAPS) {
554 assert(is_loaded(), "must be loaded");
555 if (!is_linked()) {
556 link_class_impl(false, CHECK_false);
557 }
558 return is_linked();
559 }
560
561 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
562 if (DumpSharedSpaces && is_in_error_state()) {
563 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
564 // the class has failed verification. Throwing the NoClassDefFoundError here is just
565 // a convenient way to stop repeat attempts to verify the same (bad) class.
566 //
567 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
568 // if we are executing Java code. This is not a problem for CDS dumping phase since
569 // it doesn't execute any Java code.
570 ResourceMark rm(THREAD);
571 Exceptions::fthrow(THREAD_AND_LOCATION,
572 vmSymbols::java_lang_NoClassDefFoundError(),
573 "Class %s, or one of its supertypes, failed class initialization",
574 external_name());
575 return false;
576 }
577 // return if already verified
578 if (is_linked()) {
579 return true;
580 }
581
582 // Timing
583 // timer handles recursion
584 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
585 JavaThread* jt = (JavaThread*)THREAD;
586
587 // link super class before linking this class
588 Klass* super_klass = super();
589 if (super_klass != NULL) {
590 if (super_klass->is_interface()) { // check if super class is an interface
591 ResourceMark rm(THREAD);
592 Exceptions::fthrow(
593 THREAD_AND_LOCATION,
594 vmSymbols::java_lang_IncompatibleClassChangeError(),
595 "class %s has interface %s as super class",
596 external_name(),
597 super_klass->external_name()
598 );
599 return false;
600 }
601
602 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
603 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
604 }
605
606 // link all interfaces implemented by this class before linking this class
607 Array<Klass*>* interfaces = local_interfaces();
608 int num_interfaces = interfaces->length();
609 for (int index = 0; index < num_interfaces; index++) {
610 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
611 interk->link_class_impl(throw_verifyerror, CHECK_false);
612 }
613
614
615 // If a class declares a method that uses a value class as an argument
616 // type or return value type, this value class must be loaded during the
617 // linking if this class because size and properties of the value class
618 // must be known in order to be able to perform value type optimizations.
619 // The implementation below is an approximation of this rule, the code
620 // iterates over all methods of the current class (including overridden
621 // methods), not only the methods declared by this class. This
622 // approximation makes the code simpler, and doesn't change the semantic
623 // because classes declaring methods overridden by the current class are
624 // linked (and have performed their own pre-loading) before the linking
625 // of the current class.
626 // This is also the moment where potential mismatch between the
627 // ValueTypes attribute and the kind of the class effectively loaded.
628
629
630 // Note:
631 // Value class types used for flattenable fields are loaded during
632 // the loading phase (see layout ClassFileParser::layout_fields()).
633 // Value class types used as element types for array creation
634 // are not pre-loaded. Their loading is triggered by either anewarray
635 // or multianewarray bytecodes.
636
637 {
638 ResourceMark rm(THREAD);
639 for (int i = 0; i < methods()->length(); i++) {
640 Method* m = methods()->at(i);
641 for (SignatureStream ss(m->signature()); !ss.is_done(); ss.next()) {
642 Symbol* sig = ss.as_symbol(THREAD);
643 if (is_declared_value_type(sig)) {
644 // Get current loader and protection domain first.
645 oop loader = class_loader();
646 oop protection_domain = this->protection_domain();
647
648 Klass* klass = SystemDictionary::resolve_or_fail(sig,
649 Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
650 CHECK_false);
651 if (klass == NULL) {
652 THROW_(vmSymbols::java_lang_LinkageError(), false);
653 }
654 if (!klass->is_value()) {
655 THROW_(vmSymbols::java_lang_IncompatibleClassChangeError(), false);
656 }
657 }
658 }
659 }
660 }
661
662 // in case the class is linked in the process of linking its superclasses
663 if (is_linked()) {
664 return true;
665 }
666
667 // trace only the link time for this klass that includes
668 // the verification time
669 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
670 ClassLoader::perf_class_link_selftime(),
671 ClassLoader::perf_classes_linked(),
672 jt->get_thread_stat()->perf_recursion_counts_addr(),
673 jt->get_thread_stat()->perf_timers_addr(),
674 PerfClassTraceTime::CLASS_LINK);
675
676 // verification & rewriting
677 {
678 HandleMark hm(THREAD);
679 Handle h_init_lock(THREAD, init_lock());
680 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
681 // rewritten will have been set if loader constraint error found
682 // on an earlier link attempt
683 // don't verify or rewrite if already rewritten
684 //
685
686 if (!is_linked()) {
687 if (!is_rewritten()) {
688 {
689 bool verify_ok = verify_code(throw_verifyerror, THREAD);
690 if (!verify_ok) {
691 return false;
692 }
693 }
694
695 // Just in case a side-effect of verify linked this class already
696 // (which can sometimes happen since the verifier loads classes
697 // using custom class loaders, which are free to initialize things)
698 if (is_linked()) {
699 return true;
700 }
701
702 // also sets rewritten
703 rewrite_class(CHECK_false);
704 } else if (is_shared()) {
705 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
706 }
707
708 // relocate jsrs and link methods after they are all rewritten
709 link_methods(CHECK_false);
710
711 // Initialize the vtable and interface table after
712 // methods have been rewritten since rewrite may
713 // fabricate new Method*s.
714 // also does loader constraint checking
715 //
716 // initialize_vtable and initialize_itable need to be rerun for
717 // a shared class if the class is not loaded by the NULL classloader.
718 ClassLoaderData * loader_data = class_loader_data();
719 if (!(is_shared() &&
720 loader_data->is_the_null_class_loader_data())) {
721 ResourceMark rm(THREAD);
722 vtable().initialize_vtable(true, CHECK_false);
723 itable().initialize_itable(true, CHECK_false);
724 }
725 #ifdef ASSERT
726 else {
727 vtable().verify(tty, true);
728 // In case itable verification is ever added.
729 // itable().verify(tty, true);
730 }
731 #endif
732
733 set_init_state(linked);
734 if (JvmtiExport::should_post_class_prepare()) {
735 Thread *thread = THREAD;
736 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
737 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
738 }
739 }
740 }
741 return true;
742 }
743
744
745 // Rewrite the byte codes of all of the methods of a class.
746 // The rewriter must be called exactly once. Rewriting must happen after
747 // verification but before the first method of the class is executed.
748 void InstanceKlass::rewrite_class(TRAPS) {
749 assert(is_loaded(), "must be loaded");
750 if (is_rewritten()) {
751 assert(is_shared(), "rewriting an unshared class?");
752 return;
753 }
754 Rewriter::rewrite(this, CHECK);
755 set_rewritten();
756 }
757
758 // Now relocate and link method entry points after class is rewritten.
759 // This is outside is_rewritten flag. In case of an exception, it can be
760 // executed more than once.
761 void InstanceKlass::link_methods(TRAPS) {
762 int len = methods()->length();
763 for (int i = len-1; i >= 0; i--) {
764 methodHandle m(THREAD, methods()->at(i));
765
766 // Set up method entry points for compiler and interpreter .
767 m->link_method(m, CHECK);
768 }
769 }
770
771 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
772 void InstanceKlass::initialize_super_interfaces(TRAPS) {
773 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
774 for (int i = 0; i < local_interfaces()->length(); ++i) {
775 Klass* iface = local_interfaces()->at(i);
776 InstanceKlass* ik = InstanceKlass::cast(iface);
777
778 // Initialization is depth first search ie. we start with top of the inheritance tree
779 // has_nonstatic_concrete_methods drives searching superinterfaces since it
780 // means has_nonstatic_concrete_methods in its superinterface hierarchy
781 if (ik->has_nonstatic_concrete_methods()) {
782 ik->initialize_super_interfaces(CHECK);
783 }
784
785 // Only initialize() interfaces that "declare" concrete methods.
786 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
787 ik->initialize(CHECK);
788 }
789 }
790 }
791
792 void InstanceKlass::initialize_impl(TRAPS) {
793 HandleMark hm(THREAD);
794
795 // Make sure klass is linked (verified) before initialization
796 // A class could already be verified, since it has been reflected upon.
797 link_class(CHECK);
798
799 DTRACE_CLASSINIT_PROBE(required, -1);
800
801 bool wait = false;
802
803 // refer to the JVM book page 47 for description of steps
804 // Step 1
805 {
806 Handle h_init_lock(THREAD, init_lock());
807 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
808
809 Thread *self = THREAD; // it's passed the current thread
810
811 // Step 2
812 // If we were to use wait() instead of waitInterruptibly() then
813 // we might end up throwing IE from link/symbol resolution sites
814 // that aren't expected to throw. This would wreak havoc. See 6320309.
815 while(is_being_initialized() && !is_reentrant_initialization(self)) {
816 wait = true;
817 ol.waitUninterruptibly(CHECK);
818 }
819
820 // Step 3
821 if (is_being_initialized() && is_reentrant_initialization(self)) {
822 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
823 return;
824 }
825
826 // Step 4
827 if (is_initialized()) {
828 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
829 return;
830 }
831
832 // Step 5
833 if (is_in_error_state()) {
834 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
835 ResourceMark rm(THREAD);
836 const char* desc = "Could not initialize class ";
837 const char* className = external_name();
838 size_t msglen = strlen(desc) + strlen(className) + 1;
839 char* message = NEW_RESOURCE_ARRAY(char, msglen);
840 if (NULL == message) {
841 // Out of memory: can't create detailed error message
842 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
843 } else {
844 jio_snprintf(message, msglen, "%s%s", desc, className);
845 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
846 }
847 }
848
849 // Step 6
850 set_init_state(being_initialized);
851 set_init_thread(self);
852 }
853
854 // Step 7
855 // Next, if C is a class rather than an interface, initialize it's super class and super
856 // interfaces.
857 if (!is_interface()) {
858 Klass* super_klass = super();
859 if (super_klass != NULL && super_klass->should_be_initialized()) {
860 super_klass->initialize(THREAD);
861 }
862 // If C implements any interface that declares a non-static, concrete method,
863 // the initialization of C triggers initialization of its super interfaces.
864 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
865 // having a superinterface that declares, non-static, concrete methods
866 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
867 initialize_super_interfaces(THREAD);
868 }
869
870 // If any exceptions, complete abruptly, throwing the same exception as above.
871 if (HAS_PENDING_EXCEPTION) {
872 Handle e(THREAD, PENDING_EXCEPTION);
873 CLEAR_PENDING_EXCEPTION;
874 {
875 EXCEPTION_MARK;
876 // Locks object, set state, and notify all waiting threads
877 set_initialization_state_and_notify(initialization_error, THREAD);
878 CLEAR_PENDING_EXCEPTION;
879 }
880 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
881 THROW_OOP(e());
882 }
883 }
884
885 // Step 8
886 // Initialize classes of flattenable fields
887 {
888 for (AllFieldStream fs(this); !fs.done(); fs.next()) {
889 if (fs.is_flattenable()) {
890 InstanceKlass* field_klass = InstanceKlass::cast(this->get_value_field_klass(fs.index()));
891 field_klass->initialize(CHECK);
892 }
893 }
894 }
895
896
897 // Look for aot compiled methods for this klass, including class initializer.
898 AOTLoader::load_for_klass(this, THREAD);
899
900 // Step 9
901 {
902 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
903 JavaThread* jt = (JavaThread*)THREAD;
904 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
905 // Timer includes any side effects of class initialization (resolution,
906 // etc), but not recursive entry into call_class_initializer().
907 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
908 ClassLoader::perf_class_init_selftime(),
909 ClassLoader::perf_classes_inited(),
910 jt->get_thread_stat()->perf_recursion_counts_addr(),
911 jt->get_thread_stat()->perf_timers_addr(),
912 PerfClassTraceTime::CLASS_CLINIT);
913 call_class_initializer(THREAD);
914 }
915
916 // Step 10
917 if (!HAS_PENDING_EXCEPTION) {
918 set_initialization_state_and_notify(fully_initialized, CHECK);
919 {
920 debug_only(vtable().verify(tty, true);)
921 }
922 }
923 else {
924 // Step 11 and 12
925 Handle e(THREAD, PENDING_EXCEPTION);
926 CLEAR_PENDING_EXCEPTION;
927 // JVMTI has already reported the pending exception
928 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
929 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
930 {
931 EXCEPTION_MARK;
932 set_initialization_state_and_notify(initialization_error, THREAD);
933 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
934 // JVMTI has already reported the pending exception
935 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
936 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
937 }
938 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
939 if (e->is_a(SystemDictionary::Error_klass())) {
940 THROW_OOP(e());
941 } else {
942 JavaCallArguments args(e);
943 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
944 vmSymbols::throwable_void_signature(),
945 &args);
946 }
947 }
948 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
949 }
950
951
952 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
953 Handle h_init_lock(THREAD, init_lock());
954 if (h_init_lock() != NULL) {
955 ObjectLocker ol(h_init_lock, THREAD);
956 set_init_state(state);
957 fence_and_clear_init_lock();
958 ol.notify_all(CHECK);
959 } else {
960 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
961 set_init_state(state);
962 }
963 }
964
965 // The embedded _implementor field can only record one implementor.
966 // When there are more than one implementors, the _implementor field
967 // is set to the interface Klass* itself. Following are the possible
968 // values for the _implementor field:
969 // NULL - no implementor
970 // implementor Klass* - one implementor
971 // self - more than one implementor
972 //
973 // The _implementor field only exists for interfaces.
974 void InstanceKlass::add_implementor(Klass* k) {
975 assert(Compile_lock->owned_by_self(), "");
976 assert(is_interface(), "not interface");
977 // Filter out my subinterfaces.
978 // (Note: Interfaces are never on the subklass list.)
979 if (InstanceKlass::cast(k)->is_interface()) return;
980
981 // Filter out subclasses whose supers already implement me.
982 // (Note: CHA must walk subclasses of direct implementors
983 // in order to locate indirect implementors.)
984 Klass* sk = k->super();
985 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
986 // We only need to check one immediate superclass, since the
987 // implements_interface query looks at transitive_interfaces.
988 // Any supers of the super have the same (or fewer) transitive_interfaces.
989 return;
990
991 Klass* ik = implementor();
992 if (ik == NULL) {
993 set_implementor(k);
994 } else if (ik != this) {
995 // There is already an implementor. Use itself as an indicator of
996 // more than one implementors.
997 set_implementor(this);
998 }
999
1000 // The implementor also implements the transitive_interfaces
1001 for (int index = 0; index < local_interfaces()->length(); index++) {
1002 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1003 }
1004 }
1005
1006 void InstanceKlass::init_implementor() {
1007 if (is_interface()) {
1008 set_implementor(NULL);
1009 }
1010 }
1011
1012
1013 void InstanceKlass::process_interfaces(Thread *thread) {
1014 // link this class into the implementors list of every interface it implements
1015 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1016 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1017 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1018 assert(interf->is_interface(), "expected interface");
1019 interf->add_implementor(this);
1020 }
1021 }
1022
1023 bool InstanceKlass::can_be_primary_super_slow() const {
1024 if (is_interface())
1025 return false;
1026 else
1027 return Klass::can_be_primary_super_slow();
1028 }
1029
1030 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1031 // The secondaries are the implemented interfaces.
1032 Array<Klass*>* interfaces = transitive_interfaces();
1033 int num_secondaries = num_extra_slots + interfaces->length();
1034 if (num_secondaries == 0) {
1035 // Must share this for correct bootstrapping!
1036 set_secondary_supers(Universe::the_empty_klass_array());
1037 return NULL;
1038 } else if (num_extra_slots == 0) {
1039 // The secondary super list is exactly the same as the transitive interfaces.
1040 // Redefine classes has to be careful not to delete this!
1041 set_secondary_supers(interfaces);
1042 return NULL;
1043 } else {
1044 // Copy transitive interfaces to a temporary growable array to be constructed
1045 // into the secondary super list with extra slots.
1046 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1047 for (int i = 0; i < interfaces->length(); i++) {
1048 secondaries->push(interfaces->at(i));
1049 }
1050 return secondaries;
1051 }
1052 }
1053
1054 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1055 if (k->is_interface()) {
1056 return implements_interface(k);
1057 } else {
1058 return Klass::compute_is_subtype_of(k);
1059 }
1060 }
1061
1062 bool InstanceKlass::implements_interface(Klass* k) const {
1063 if (this == k) return true;
1064 assert(k->is_interface(), "should be an interface class");
1065 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1066 if (transitive_interfaces()->at(i) == k) {
1067 return true;
1068 }
1069 }
1070 return false;
1071 }
1072
1073 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1074 // Verify direct super interface
1075 if (this == k) return true;
1076 assert(k->is_interface(), "should be an interface class");
1077 for (int i = 0; i < local_interfaces()->length(); i++) {
1078 if (local_interfaces()->at(i) == k) {
1079 return true;
1080 }
1081 }
1082 return false;
1083 }
1084
1085 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1086 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1087 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1088 report_java_out_of_memory("Requested array size exceeds VM limit");
1089 JvmtiExport::post_array_size_exhausted();
1090 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1091 }
1092 int size = objArrayOopDesc::object_size(length);
1093 Klass* ak = array_klass(n, CHECK_NULL);
1094 objArrayOop o =
1095 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1096 return o;
1097 }
1098
1099 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1100 if (TraceFinalizerRegistration) {
1101 tty->print("Registered ");
1102 i->print_value_on(tty);
1103 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1104 }
1105 instanceHandle h_i(THREAD, i);
1106 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1107 JavaValue result(T_VOID);
1108 JavaCallArguments args(h_i);
1109 methodHandle mh (THREAD, Universe::finalizer_register_method());
1110 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1111 return h_i();
1112 }
1113
1114 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1115 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1116 int size = size_helper(); // Query before forming handle.
1117
1118 instanceOop i;
1119
1120 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1121 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1122 i = register_finalizer(i, CHECK_NULL);
1123 }
1124 return i;
1125 }
1126
1127 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1128 if (is_interface() || is_abstract()) {
1129 ResourceMark rm(THREAD);
1130 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1131 : vmSymbols::java_lang_InstantiationException(), external_name());
1132 }
1133 if (this == SystemDictionary::Class_klass()) {
1134 ResourceMark rm(THREAD);
1135 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1136 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1137 }
1138 }
1139
1140 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1141 // Need load-acquire for lock-free read
1142 if (array_klasses_acquire() == NULL) {
1143 if (or_null) return NULL;
1144
1145 ResourceMark rm;
1146 JavaThread *jt = (JavaThread *)THREAD;
1147 {
1148 // Atomic creation of array_klasses
1149 MutexLocker mc(Compile_lock, THREAD); // for vtables
1150 MutexLocker ma(MultiArray_lock, THREAD);
1151
1152 // Check if update has already taken place
1153 if (array_klasses() == NULL) {
1154 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1155 // use 'release' to pair with lock-free load
1156 release_set_array_klasses(k);
1157 }
1158 }
1159 }
1160 // _this will always be set at this point
1161 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1162 if (or_null) {
1163 return oak->array_klass_or_null(n);
1164 }
1165 return oak->array_klass(n, THREAD);
1166 }
1167
1168 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1169 return array_klass_impl(or_null, 1, THREAD);
1170 }
1171
1172 static int call_class_initializer_counter = 0; // for debugging
1173
1174 Method* InstanceKlass::class_initializer() const {
1175 Method* clinit = find_method(
1176 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1177 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1178 return clinit;
1179 }
1180 return NULL;
1181 }
1182
1183 void InstanceKlass::call_class_initializer(TRAPS) {
1184 if (ReplayCompiles &&
1185 (ReplaySuppressInitializers == 1 ||
1186 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1187 // Hide the existence of the initializer for the purpose of replaying the compile
1188 return;
1189 }
1190
1191 methodHandle h_method(THREAD, class_initializer());
1192 assert(!is_initialized(), "we cannot initialize twice");
1193 LogTarget(Info, class, init) lt;
1194 if (lt.is_enabled()) {
1195 ResourceMark rm;
1196 LogStream ls(lt);
1197 ls.print("%d Initializing ", call_class_initializer_counter++);
1198 name()->print_value_on(&ls);
1199 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1200 }
1201 if (h_method() != NULL) {
1202 JavaCallArguments args; // No arguments
1203 JavaValue result(T_VOID);
1204 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1205 }
1206 }
1207
1208
1209 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1210 InterpreterOopMap* entry_for) {
1211 // Lazily create the _oop_map_cache at first request
1212 // Lock-free access requires load_acquire.
1213 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1214 if (oop_map_cache == NULL) {
1215 MutexLockerEx x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1216 // Check if _oop_map_cache was allocated while we were waiting for this lock
1217 if ((oop_map_cache = _oop_map_cache) == NULL) {
1218 oop_map_cache = new OopMapCache();
1219 // Ensure _oop_map_cache is stable, since it is examined without a lock
1220 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1221 }
1222 }
1223 // _oop_map_cache is constant after init; lookup below does its own locking.
1224 oop_map_cache->lookup(method, bci, entry_for);
1225 }
1226
1227
1228 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1229 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1230 Symbol* f_name = fs.name();
1231 Symbol* f_sig = fs.signature();
1232 if (f_name == name && f_sig == sig) {
1233 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1234 return true;
1235 }
1236 }
1237 return false;
1238 }
1239
1240
1241 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1242 const int n = local_interfaces()->length();
1243 for (int i = 0; i < n; i++) {
1244 Klass* intf1 = local_interfaces()->at(i);
1245 assert(intf1->is_interface(), "just checking type");
1246 // search for field in current interface
1247 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1248 assert(fd->is_static(), "interface field must be static");
1249 return intf1;
1250 }
1251 // search for field in direct superinterfaces
1252 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1253 if (intf2 != NULL) return intf2;
1254 }
1255 // otherwise field lookup fails
1256 return NULL;
1257 }
1258
1259
1260 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1261 // search order according to newest JVM spec (5.4.3.2, p.167).
1262 // 1) search for field in current klass
1263 if (find_local_field(name, sig, fd)) {
1264 return const_cast<InstanceKlass*>(this);
1265 }
1266 // 2) search for field recursively in direct superinterfaces
1267 { Klass* intf = find_interface_field(name, sig, fd);
1268 if (intf != NULL) return intf;
1269 }
1270 // 3) apply field lookup recursively if superclass exists
1271 { Klass* supr = super();
1272 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1273 }
1274 // 4) otherwise field lookup fails
1275 return NULL;
1276 }
1277
1278
1279 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1280 // search order according to newest JVM spec (5.4.3.2, p.167).
1281 // 1) search for field in current klass
1282 if (find_local_field(name, sig, fd)) {
1283 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1284 }
1285 // 2) search for field recursively in direct superinterfaces
1286 if (is_static) {
1287 Klass* intf = find_interface_field(name, sig, fd);
1288 if (intf != NULL) return intf;
1289 }
1290 // 3) apply field lookup recursively if superclass exists
1291 { Klass* supr = super();
1292 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1293 }
1294 // 4) otherwise field lookup fails
1295 return NULL;
1296 }
1297
1298
1299 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1300 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1301 if (fs.offset() == offset) {
1302 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1303 if (fd->is_static() == is_static) return true;
1304 }
1305 }
1306 return false;
1307 }
1308
1309
1310 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1311 Klass* klass = const_cast<InstanceKlass*>(this);
1312 while (klass != NULL) {
1313 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1314 return true;
1315 }
1316 klass = klass->super();
1317 }
1318 return false;
1319 }
1320
1321
1322 void InstanceKlass::methods_do(void f(Method* method)) {
1323 // Methods aren't stable until they are loaded. This can be read outside
1324 // a lock through the ClassLoaderData for profiling
1325 if (!is_loaded()) {
1326 return;
1327 }
1328
1329 int len = methods()->length();
1330 for (int index = 0; index < len; index++) {
1331 Method* m = methods()->at(index);
1332 assert(m->is_method(), "must be method");
1333 f(m);
1334 }
1335 }
1336
1337
1338 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1339 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1340 if (fs.access_flags().is_static()) {
1341 fieldDescriptor& fd = fs.field_descriptor();
1342 cl->do_field(&fd);
1343 }
1344 }
1345 }
1346
1347
1348 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1349 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1350 if (fs.access_flags().is_static()) {
1351 fieldDescriptor& fd = fs.field_descriptor();
1352 f(&fd, mirror, CHECK);
1353 }
1354 }
1355 }
1356
1357
1358 static int compare_fields_by_offset(int* a, int* b) {
1359 return a[0] - b[0];
1360 }
1361
1362 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1363 InstanceKlass* super = superklass();
1364 if (super != NULL) {
1365 super->do_nonstatic_fields(cl);
1366 }
1367 fieldDescriptor fd;
1368 int length = java_fields_count();
1369 // In DebugInfo nonstatic fields are sorted by offset.
1370 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1371 int j = 0;
1372 for (int i = 0; i < length; i += 1) {
1373 fd.reinitialize(this, i);
1374 if (!fd.is_static()) {
1375 fields_sorted[j + 0] = fd.offset();
1376 fields_sorted[j + 1] = i;
1377 j += 2;
1378 }
1379 }
1380 if (j > 0) {
1381 length = j;
1382 // _sort_Fn is defined in growableArray.hpp.
1383 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1384 for (int i = 0; i < length; i += 2) {
1385 fd.reinitialize(this, fields_sorted[i + 1]);
1386 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1387 cl->do_field(&fd);
1388 }
1389 }
1390 FREE_C_HEAP_ARRAY(int, fields_sorted);
1391 }
1392
1393
1394 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1395 if (array_klasses() != NULL)
1396 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1397 }
1398
1399 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1400 if (array_klasses() != NULL)
1401 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1402 }
1403
1404 #ifdef ASSERT
1405 static int linear_search(const Array<Method*>* methods,
1406 const Symbol* name,
1407 const Symbol* signature) {
1408 const int len = methods->length();
1409 for (int index = 0; index < len; index++) {
1410 const Method* const m = methods->at(index);
1411 assert(m->is_method(), "must be method");
1412 if (m->signature() == signature && m->name() == name) {
1413 return index;
1414 }
1415 }
1416 return -1;
1417 }
1418 #endif
1419
1420 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1421 int len = methods->length();
1422 // methods are sorted, so do binary search
1423 int l = 0;
1424 int h = len - 1;
1425 while (l <= h) {
1426 int mid = (l + h) >> 1;
1427 Method* m = methods->at(mid);
1428 assert(m->is_method(), "must be method");
1429 int res = m->name()->fast_compare(name);
1430 if (res == 0) {
1431 return mid;
1432 } else if (res < 0) {
1433 l = mid + 1;
1434 } else {
1435 h = mid - 1;
1436 }
1437 }
1438 return -1;
1439 }
1440
1441 // find_method looks up the name/signature in the local methods array
1442 Method* InstanceKlass::find_method(const Symbol* name,
1443 const Symbol* signature) const {
1444 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1445 }
1446
1447 Method* InstanceKlass::find_method_impl(const Symbol* name,
1448 const Symbol* signature,
1449 OverpassLookupMode overpass_mode,
1450 StaticLookupMode static_mode,
1451 PrivateLookupMode private_mode) const {
1452 return InstanceKlass::find_method_impl(methods(),
1453 name,
1454 signature,
1455 overpass_mode,
1456 static_mode,
1457 private_mode);
1458 }
1459
1460 // find_instance_method looks up the name/signature in the local methods array
1461 // and skips over static methods
1462 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1463 const Symbol* name,
1464 const Symbol* signature) {
1465 Method* const meth = InstanceKlass::find_method_impl(methods,
1466 name,
1467 signature,
1468 find_overpass,
1469 skip_static,
1470 find_private);
1471 assert(((meth == NULL) || !meth->is_static()),
1472 "find_instance_method should have skipped statics");
1473 return meth;
1474 }
1475
1476 // find_instance_method looks up the name/signature in the local methods array
1477 // and skips over static methods
1478 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1479 return InstanceKlass::find_instance_method(methods(), name, signature);
1480 }
1481
1482 // Find looks up the name/signature in the local methods array
1483 // and filters on the overpass, static and private flags
1484 // This returns the first one found
1485 // note that the local methods array can have up to one overpass, one static
1486 // and one instance (private or not) with the same name/signature
1487 Method* InstanceKlass::find_local_method(const Symbol* name,
1488 const Symbol* signature,
1489 OverpassLookupMode overpass_mode,
1490 StaticLookupMode static_mode,
1491 PrivateLookupMode private_mode) const {
1492 return InstanceKlass::find_method_impl(methods(),
1493 name,
1494 signature,
1495 overpass_mode,
1496 static_mode,
1497 private_mode);
1498 }
1499
1500 // Find looks up the name/signature in the local methods array
1501 // and filters on the overpass, static and private flags
1502 // This returns the first one found
1503 // note that the local methods array can have up to one overpass, one static
1504 // and one instance (private or not) with the same name/signature
1505 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1506 const Symbol* name,
1507 const Symbol* signature,
1508 OverpassLookupMode overpass_mode,
1509 StaticLookupMode static_mode,
1510 PrivateLookupMode private_mode) {
1511 return InstanceKlass::find_method_impl(methods,
1512 name,
1513 signature,
1514 overpass_mode,
1515 static_mode,
1516 private_mode);
1517 }
1518
1519 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1520 const Symbol* name,
1521 const Symbol* signature) {
1522 return InstanceKlass::find_method_impl(methods,
1523 name,
1524 signature,
1525 find_overpass,
1526 find_static,
1527 find_private);
1528 }
1529
1530 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1531 const Symbol* name,
1532 const Symbol* signature,
1533 OverpassLookupMode overpass_mode,
1534 StaticLookupMode static_mode,
1535 PrivateLookupMode private_mode) {
1536 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1537 return hit >= 0 ? methods->at(hit): NULL;
1538 }
1539
1540 // true if method matches signature and conforms to skipping_X conditions.
1541 static bool method_matches(const Method* m,
1542 const Symbol* signature,
1543 bool skipping_overpass,
1544 bool skipping_static,
1545 bool skipping_private) {
1546 return ((m->signature() == signature) &&
1547 (!skipping_overpass || !m->is_overpass()) &&
1548 (!skipping_static || !m->is_static()) &&
1549 (!skipping_private || !m->is_private()));
1550 }
1551
1552 // Used directly for default_methods to find the index into the
1553 // default_vtable_indices, and indirectly by find_method
1554 // find_method_index looks in the local methods array to return the index
1555 // of the matching name/signature. If, overpass methods are being ignored,
1556 // the search continues to find a potential non-overpass match. This capability
1557 // is important during method resolution to prefer a static method, for example,
1558 // over an overpass method.
1559 // There is the possibility in any _method's array to have the same name/signature
1560 // for a static method, an overpass method and a local instance method
1561 // To correctly catch a given method, the search criteria may need
1562 // to explicitly skip the other two. For local instance methods, it
1563 // is often necessary to skip private methods
1564 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1565 const Symbol* name,
1566 const Symbol* signature,
1567 OverpassLookupMode overpass_mode,
1568 StaticLookupMode static_mode,
1569 PrivateLookupMode private_mode) {
1570 const bool skipping_overpass = (overpass_mode == skip_overpass);
1571 const bool skipping_static = (static_mode == skip_static);
1572 const bool skipping_private = (private_mode == skip_private);
1573 const int hit = binary_search(methods, name);
1574 if (hit != -1) {
1575 const Method* const m = methods->at(hit);
1576
1577 // Do linear search to find matching signature. First, quick check
1578 // for common case, ignoring overpasses if requested.
1579 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1580 return hit;
1581 }
1582
1583 // search downwards through overloaded methods
1584 int i;
1585 for (i = hit - 1; i >= 0; --i) {
1586 const Method* const m = methods->at(i);
1587 assert(m->is_method(), "must be method");
1588 if (m->name() != name) {
1589 break;
1590 }
1591 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1592 return i;
1593 }
1594 }
1595 // search upwards
1596 for (i = hit + 1; i < methods->length(); ++i) {
1597 const Method* const m = methods->at(i);
1598 assert(m->is_method(), "must be method");
1599 if (m->name() != name) {
1600 break;
1601 }
1602 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1603 return i;
1604 }
1605 }
1606 // not found
1607 #ifdef ASSERT
1608 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1609 linear_search(methods, name, signature);
1610 assert(-1 == index, "binary search should have found entry %d", index);
1611 #endif
1612 }
1613 return -1;
1614 }
1615
1616 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1617 return find_method_by_name(methods(), name, end);
1618 }
1619
1620 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1621 const Symbol* name,
1622 int* end_ptr) {
1623 assert(end_ptr != NULL, "just checking");
1624 int start = binary_search(methods, name);
1625 int end = start + 1;
1626 if (start != -1) {
1627 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1628 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1629 *end_ptr = end;
1630 return start;
1631 }
1632 return -1;
1633 }
1634
1635 // uncached_lookup_method searches both the local class methods array and all
1636 // superclasses methods arrays, skipping any overpass methods in superclasses.
1637 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1638 const Symbol* signature,
1639 OverpassLookupMode overpass_mode) const {
1640 OverpassLookupMode overpass_local_mode = overpass_mode;
1641 const Klass* klass = this;
1642 while (klass != NULL) {
1643 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1644 signature,
1645 overpass_local_mode,
1646 find_static,
1647 find_private);
1648 if (method != NULL) {
1649 return method;
1650 }
1651 klass = klass->super();
1652 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1653 }
1654 return NULL;
1655 }
1656
1657 #ifdef ASSERT
1658 // search through class hierarchy and return true if this class or
1659 // one of the superclasses was redefined
1660 bool InstanceKlass::has_redefined_this_or_super() const {
1661 const Klass* klass = this;
1662 while (klass != NULL) {
1663 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1664 return true;
1665 }
1666 klass = klass->super();
1667 }
1668 return false;
1669 }
1670 #endif
1671
1672 // lookup a method in the default methods list then in all transitive interfaces
1673 // Do NOT return private or static methods
1674 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1675 Symbol* signature) const {
1676 Method* m = NULL;
1677 if (default_methods() != NULL) {
1678 m = find_method(default_methods(), name, signature);
1679 }
1680 // Look up interfaces
1681 if (m == NULL) {
1682 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1683 }
1684 return m;
1685 }
1686
1687 // lookup a method in all the interfaces that this class implements
1688 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1689 // They should only be found in the initial InterfaceMethodRef
1690 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1691 Symbol* signature,
1692 DefaultsLookupMode defaults_mode) const {
1693 Array<Klass*>* all_ifs = transitive_interfaces();
1694 int num_ifs = all_ifs->length();
1695 InstanceKlass *ik = NULL;
1696 for (int i = 0; i < num_ifs; i++) {
1697 ik = InstanceKlass::cast(all_ifs->at(i));
1698 Method* m = ik->lookup_method(name, signature);
1699 if (m != NULL && m->is_public() && !m->is_static() &&
1700 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1701 return m;
1702 }
1703 }
1704 return NULL;
1705 }
1706
1707 /* jni_id_for_impl for jfieldIds only */
1708 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1709 MutexLocker ml(JfieldIdCreation_lock);
1710 // Retry lookup after we got the lock
1711 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1712 if (probe == NULL) {
1713 // Slow case, allocate new static field identifier
1714 probe = new JNIid(this, offset, jni_ids());
1715 set_jni_ids(probe);
1716 }
1717 return probe;
1718 }
1719
1720
1721 /* jni_id_for for jfieldIds only */
1722 JNIid* InstanceKlass::jni_id_for(int offset) {
1723 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1724 if (probe == NULL) {
1725 probe = jni_id_for_impl(offset);
1726 }
1727 return probe;
1728 }
1729
1730 u2 InstanceKlass::enclosing_method_data(int offset) const {
1731 const Array<jushort>* const inner_class_list = inner_classes();
1732 if (inner_class_list == NULL) {
1733 return 0;
1734 }
1735 const int length = inner_class_list->length();
1736 if (length % inner_class_next_offset == 0) {
1737 return 0;
1738 }
1739 const int index = length - enclosing_method_attribute_size;
1740 assert(offset < enclosing_method_attribute_size, "invalid offset");
1741 return inner_class_list->at(index + offset);
1742 }
1743
1744 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1745 u2 method_index) {
1746 Array<jushort>* inner_class_list = inner_classes();
1747 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1748 int length = inner_class_list->length();
1749 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1750 int index = length - enclosing_method_attribute_size;
1751 inner_class_list->at_put(
1752 index + enclosing_method_class_index_offset, class_index);
1753 inner_class_list->at_put(
1754 index + enclosing_method_method_index_offset, method_index);
1755 }
1756 }
1757
1758 // Lookup or create a jmethodID.
1759 // This code is called by the VMThread and JavaThreads so the
1760 // locking has to be done very carefully to avoid deadlocks
1761 // and/or other cache consistency problems.
1762 //
1763 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1764 size_t idnum = (size_t)method_h->method_idnum();
1765 jmethodID* jmeths = methods_jmethod_ids_acquire();
1766 size_t length = 0;
1767 jmethodID id = NULL;
1768
1769 // We use a double-check locking idiom here because this cache is
1770 // performance sensitive. In the normal system, this cache only
1771 // transitions from NULL to non-NULL which is safe because we use
1772 // release_set_methods_jmethod_ids() to advertise the new cache.
1773 // A partially constructed cache should never be seen by a racing
1774 // thread. We also use release_store() to save a new jmethodID
1775 // in the cache so a partially constructed jmethodID should never be
1776 // seen either. Cache reads of existing jmethodIDs proceed without a
1777 // lock, but cache writes of a new jmethodID requires uniqueness and
1778 // creation of the cache itself requires no leaks so a lock is
1779 // generally acquired in those two cases.
1780 //
1781 // If the RedefineClasses() API has been used, then this cache can
1782 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1783 // Cache creation requires no leaks and we require safety between all
1784 // cache accesses and freeing of the old cache so a lock is generally
1785 // acquired when the RedefineClasses() API has been used.
1786
1787 if (jmeths != NULL) {
1788 // the cache already exists
1789 if (!idnum_can_increment()) {
1790 // the cache can't grow so we can just get the current values
1791 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1792 } else {
1793 // cache can grow so we have to be more careful
1794 if (Threads::number_of_threads() == 0 ||
1795 SafepointSynchronize::is_at_safepoint()) {
1796 // we're single threaded or at a safepoint - no locking needed
1797 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1798 } else {
1799 MutexLocker ml(JmethodIdCreation_lock);
1800 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1801 }
1802 }
1803 }
1804 // implied else:
1805 // we need to allocate a cache so default length and id values are good
1806
1807 if (jmeths == NULL || // no cache yet
1808 length <= idnum || // cache is too short
1809 id == NULL) { // cache doesn't contain entry
1810
1811 // This function can be called by the VMThread so we have to do all
1812 // things that might block on a safepoint before grabbing the lock.
1813 // Otherwise, we can deadlock with the VMThread or have a cache
1814 // consistency issue. These vars keep track of what we might have
1815 // to free after the lock is dropped.
1816 jmethodID to_dealloc_id = NULL;
1817 jmethodID* to_dealloc_jmeths = NULL;
1818
1819 // may not allocate new_jmeths or use it if we allocate it
1820 jmethodID* new_jmeths = NULL;
1821 if (length <= idnum) {
1822 // allocate a new cache that might be used
1823 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1824 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1825 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1826 // cache size is stored in element[0], other elements offset by one
1827 new_jmeths[0] = (jmethodID)size;
1828 }
1829
1830 // allocate a new jmethodID that might be used
1831 jmethodID new_id = NULL;
1832 if (method_h->is_old() && !method_h->is_obsolete()) {
1833 // The method passed in is old (but not obsolete), we need to use the current version
1834 Method* current_method = method_with_idnum((int)idnum);
1835 assert(current_method != NULL, "old and but not obsolete, so should exist");
1836 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1837 } else {
1838 // It is the current version of the method or an obsolete method,
1839 // use the version passed in
1840 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1841 }
1842
1843 if (Threads::number_of_threads() == 0 ||
1844 SafepointSynchronize::is_at_safepoint()) {
1845 // we're single threaded or at a safepoint - no locking needed
1846 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1847 &to_dealloc_id, &to_dealloc_jmeths);
1848 } else {
1849 MutexLocker ml(JmethodIdCreation_lock);
1850 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1851 &to_dealloc_id, &to_dealloc_jmeths);
1852 }
1853
1854 // The lock has been dropped so we can free resources.
1855 // Free up either the old cache or the new cache if we allocated one.
1856 if (to_dealloc_jmeths != NULL) {
1857 FreeHeap(to_dealloc_jmeths);
1858 }
1859 // free up the new ID since it wasn't needed
1860 if (to_dealloc_id != NULL) {
1861 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1862 }
1863 }
1864 return id;
1865 }
1866
1867 // Figure out how many jmethodIDs haven't been allocated, and make
1868 // sure space for them is pre-allocated. This makes getting all
1869 // method ids much, much faster with classes with more than 8
1870 // methods, and has a *substantial* effect on performance with jvmti
1871 // code that loads all jmethodIDs for all classes.
1872 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1873 int new_jmeths = 0;
1874 int length = methods()->length();
1875 for (int index = start_offset; index < length; index++) {
1876 Method* m = methods()->at(index);
1877 jmethodID id = m->find_jmethod_id_or_null();
1878 if (id == NULL) {
1879 new_jmeths++;
1880 }
1881 }
1882 if (new_jmeths != 0) {
1883 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1884 }
1885 }
1886
1887 // Common code to fetch the jmethodID from the cache or update the
1888 // cache with the new jmethodID. This function should never do anything
1889 // that causes the caller to go to a safepoint or we can deadlock with
1890 // the VMThread or have cache consistency issues.
1891 //
1892 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1893 size_t idnum, jmethodID new_id,
1894 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1895 jmethodID** to_dealloc_jmeths_p) {
1896 assert(new_id != NULL, "sanity check");
1897 assert(to_dealloc_id_p != NULL, "sanity check");
1898 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1899 assert(Threads::number_of_threads() == 0 ||
1900 SafepointSynchronize::is_at_safepoint() ||
1901 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1902
1903 // reacquire the cache - we are locked, single threaded or at a safepoint
1904 jmethodID* jmeths = methods_jmethod_ids_acquire();
1905 jmethodID id = NULL;
1906 size_t length = 0;
1907
1908 if (jmeths == NULL || // no cache yet
1909 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1910 if (jmeths != NULL) {
1911 // copy any existing entries from the old cache
1912 for (size_t index = 0; index < length; index++) {
1913 new_jmeths[index+1] = jmeths[index+1];
1914 }
1915 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1916 }
1917 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1918 } else {
1919 // fetch jmethodID (if any) from the existing cache
1920 id = jmeths[idnum+1];
1921 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1922 }
1923 if (id == NULL) {
1924 // No matching jmethodID in the existing cache or we have a new
1925 // cache or we just grew the cache. This cache write is done here
1926 // by the first thread to win the foot race because a jmethodID
1927 // needs to be unique once it is generally available.
1928 id = new_id;
1929
1930 // The jmethodID cache can be read while unlocked so we have to
1931 // make sure the new jmethodID is complete before installing it
1932 // in the cache.
1933 OrderAccess::release_store(&jmeths[idnum+1], id);
1934 } else {
1935 *to_dealloc_id_p = new_id; // save new id for later delete
1936 }
1937 return id;
1938 }
1939
1940
1941 // Common code to get the jmethodID cache length and the jmethodID
1942 // value at index idnum if there is one.
1943 //
1944 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1945 size_t idnum, size_t *length_p, jmethodID* id_p) {
1946 assert(cache != NULL, "sanity check");
1947 assert(length_p != NULL, "sanity check");
1948 assert(id_p != NULL, "sanity check");
1949
1950 // cache size is stored in element[0], other elements offset by one
1951 *length_p = (size_t)cache[0];
1952 if (*length_p <= idnum) { // cache is too short
1953 *id_p = NULL;
1954 } else {
1955 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1956 }
1957 }
1958
1959
1960 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1961 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1962 size_t idnum = (size_t)method->method_idnum();
1963 jmethodID* jmeths = methods_jmethod_ids_acquire();
1964 size_t length; // length assigned as debugging crumb
1965 jmethodID id = NULL;
1966 if (jmeths != NULL && // If there is a cache
1967 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1968 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1969 }
1970 return id;
1971 }
1972
1973 inline DependencyContext InstanceKlass::dependencies() {
1974 DependencyContext dep_context(&_dep_context);
1975 return dep_context;
1976 }
1977
1978 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1979 return dependencies().mark_dependent_nmethods(changes);
1980 }
1981
1982 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1983 dependencies().add_dependent_nmethod(nm);
1984 }
1985
1986 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1987 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1988 }
1989
1990 #ifndef PRODUCT
1991 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1992 dependencies().print_dependent_nmethods(verbose);
1993 }
1994
1995 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1996 return dependencies().is_dependent_nmethod(nm);
1997 }
1998 #endif //PRODUCT
1999
2000 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2001 clean_implementors_list(is_alive);
2002 clean_method_data(is_alive);
2003
2004 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2005 DependencyContext dep_context(&_dep_context);
2006 dep_context.expunge_stale_entries();
2007 }
2008
2009 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2010 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2011 if (is_interface()) {
2012 if (ClassUnloading) {
2013 Klass* impl = implementor();
2014 if (impl != NULL) {
2015 if (!impl->is_loader_alive(is_alive)) {
2016 // remove this guy
2017 Klass** klass = adr_implementor();
2018 assert(klass != NULL, "null klass");
2019 if (klass != NULL) {
2020 *klass = NULL;
2021 }
2022 }
2023 }
2024 }
2025 }
2026 }
2027
2028 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2029 for (int m = 0; m < methods()->length(); m++) {
2030 MethodData* mdo = methods()->at(m)->method_data();
2031 if (mdo != NULL) {
2032 mdo->clean_method_data(is_alive);
2033 }
2034 }
2035 }
2036
2037 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2038 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2039 ResourceMark rm;
2040 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2041 return false;
2042 }
2043
2044 Array<Klass*>* local_interfaces = this->local_interfaces();
2045 if (local_interfaces != NULL) {
2046 int length = local_interfaces->length();
2047 for (int i = 0; i < length; i++) {
2048 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2049 if (!intf->has_passed_fingerprint_check()) {
2050 ResourceMark rm;
2051 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2052 return false;
2053 }
2054 }
2055 }
2056
2057 return true;
2058 }
2059
2060 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) {
2061 #if INCLUDE_AOT
2062 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2063 if (CalculateClassFingerprint) {
2064 // (1) We are running AOT to generate a shared library.
2065 return true;
2066 }
2067 if (DumpSharedSpaces) {
2068 // (2) We are running -Xshare:dump to create a shared archive
2069 return true;
2070 }
2071 if (UseAOT && is_anonymous) {
2072 // (3) We are using AOT code from a shared library and see an anonymous class
2073 return true;
2074 }
2075 #endif
2076
2077 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2078 // but do not store the 64-bit fingerprint to save space.
2079 return false;
2080 }
2081
2082 bool InstanceKlass::has_stored_fingerprint() const {
2083 #if INCLUDE_AOT
2084 return should_store_fingerprint() || is_shared();
2085 #else
2086 return false;
2087 #endif
2088 }
2089
2090 uint64_t InstanceKlass::get_stored_fingerprint() const {
2091 address adr = adr_fingerprint();
2092 if (adr != NULL) {
2093 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2094 }
2095 return 0;
2096 }
2097
2098 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2099 address adr = adr_fingerprint();
2100 if (adr != NULL) {
2101 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2102
2103 ResourceMark rm;
2104 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2105 }
2106 }
2107
2108 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2109 Klass::metaspace_pointers_do(it);
2110
2111 if (log_is_enabled(Trace, cds)) {
2112 ResourceMark rm;
2113 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2114 }
2115
2116 it->push(&_annotations);
2117 it->push((Klass**)&_array_klasses);
2118 it->push(&_constants);
2119 it->push(&_inner_classes);
2120 it->push(&_array_name);
2121 #if INCLUDE_JVMTI
2122 it->push(&_previous_versions);
2123 #endif
2124 it->push(&_methods);
2125 it->push(&_default_methods);
2126 it->push(&_local_interfaces);
2127 it->push(&_transitive_interfaces);
2128 it->push(&_method_ordering);
2129 it->push(&_default_vtable_indices);
2130 it->push(&_fields);
2131
2132 if (itable_length() > 0) {
2133 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2134 int method_table_offset_in_words = ioe->offset()/wordSize;
2135 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2136 / itableOffsetEntry::size();
2137
2138 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2139 if (ioe->interface_klass() != NULL) {
2140 it->push(ioe->interface_klass_addr());
2141 itableMethodEntry* ime = ioe->first_method_entry(this);
2142 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2143 for (int index = 0; index < n; index ++) {
2144 it->push(ime[index].method_addr());
2145 }
2146 }
2147 }
2148 }
2149 }
2150
2151 void InstanceKlass::remove_unshareable_info() {
2152 Klass::remove_unshareable_info();
2153
2154 if (is_in_error_state()) {
2155 // Classes are attempted to link during dumping and may fail,
2156 // but these classes are still in the dictionary and class list in CLD.
2157 // Check in_error state first because in_error is > linked state, so
2158 // is_linked() is true.
2159 // If there's a linking error, there is nothing else to remove.
2160 return;
2161 }
2162
2163 // Unlink the class
2164 if (is_linked()) {
2165 unlink_class();
2166 }
2167 init_implementor();
2168
2169 constants()->remove_unshareable_info();
2170
2171 for (int i = 0; i < methods()->length(); i++) {
2172 Method* m = methods()->at(i);
2173 m->remove_unshareable_info();
2174 }
2175
2176 // do array classes also.
2177 if (array_klasses() != NULL) {
2178 array_klasses()->remove_unshareable_info();
2179 }
2180
2181 // These are not allocated from metaspace, but they should should all be empty
2182 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2183 guarantee(_source_debug_extension == NULL, "must be");
2184 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2185 guarantee(_osr_nmethods_head == NULL, "must be");
2186
2187 #if INCLUDE_JVMTI
2188 guarantee(_breakpoints == NULL, "must be");
2189 guarantee(_previous_versions == NULL, "must be");
2190 #endif
2191
2192 _init_thread = NULL;
2193 _methods_jmethod_ids = NULL;
2194 _jni_ids = NULL;
2195 _oop_map_cache = NULL;
2196 }
2197
2198 void InstanceKlass::remove_java_mirror() {
2199 Klass::remove_java_mirror();
2200
2201 // do array classes also.
2202 if (array_klasses() != NULL) {
2203 array_klasses()->remove_java_mirror();
2204 }
2205 }
2206
2207 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2208 set_package(loader_data, CHECK);
2209 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2210
2211 Array<Method*>* methods = this->methods();
2212 int num_methods = methods->length();
2213 for (int index2 = 0; index2 < num_methods; ++index2) {
2214 methodHandle m(THREAD, methods->at(index2));
2215 m->restore_unshareable_info(CHECK);
2216 }
2217 if (JvmtiExport::has_redefined_a_class()) {
2218 // Reinitialize vtable because RedefineClasses may have changed some
2219 // entries in this vtable for super classes so the CDS vtable might
2220 // point to old or obsolete entries. RedefineClasses doesn't fix up
2221 // vtables in the shared system dictionary, only the main one.
2222 // It also redefines the itable too so fix that too.
2223 ResourceMark rm(THREAD);
2224 vtable().initialize_vtable(false, CHECK);
2225 itable().initialize_itable(false, CHECK);
2226 }
2227
2228 // restore constant pool resolved references
2229 constants()->restore_unshareable_info(CHECK);
2230
2231 if (array_klasses() != NULL) {
2232 // Array classes have null protection domain.
2233 // --> see ArrayKlass::complete_create_array_klass()
2234 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2235 }
2236 }
2237
2238 // returns true IFF is_in_error_state() has been changed as a result of this call.
2239 bool InstanceKlass::check_sharing_error_state() {
2240 assert(DumpSharedSpaces, "should only be called during dumping");
2241 bool old_state = is_in_error_state();
2242
2243 if (!is_in_error_state()) {
2244 bool bad = false;
2245 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2246 if (sup->is_in_error_state()) {
2247 bad = true;
2248 break;
2249 }
2250 }
2251 if (!bad) {
2252 Array<Klass*>* interfaces = transitive_interfaces();
2253 for (int i = 0; i < interfaces->length(); i++) {
2254 Klass* iface = interfaces->at(i);
2255 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2256 bad = true;
2257 break;
2258 }
2259 }
2260 }
2261
2262 if (bad) {
2263 set_in_error_state();
2264 }
2265 }
2266
2267 return (old_state != is_in_error_state());
2268 }
2269
2270 #if INCLUDE_JVMTI
2271 static void clear_all_breakpoints(Method* m) {
2272 m->clear_all_breakpoints();
2273 }
2274 #endif
2275
2276 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2277 // notify the debugger
2278 if (JvmtiExport::should_post_class_unload()) {
2279 JvmtiExport::post_class_unload(ik);
2280 }
2281
2282 // notify ClassLoadingService of class unload
2283 ClassLoadingService::notify_class_unloaded(ik);
2284 }
2285
2286 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2287 // Clean up C heap
2288 ik->release_C_heap_structures();
2289 ik->constants()->release_C_heap_structures();
2290 }
2291
2292 void InstanceKlass::release_C_heap_structures() {
2293 // Can't release the constant pool here because the constant pool can be
2294 // deallocated separately from the InstanceKlass for default methods and
2295 // redefine classes.
2296
2297 // Deallocate oop map cache
2298 if (_oop_map_cache != NULL) {
2299 delete _oop_map_cache;
2300 _oop_map_cache = NULL;
2301 }
2302
2303 // Deallocate JNI identifiers for jfieldIDs
2304 JNIid::deallocate(jni_ids());
2305 set_jni_ids(NULL);
2306
2307 jmethodID* jmeths = methods_jmethod_ids_acquire();
2308 if (jmeths != (jmethodID*)NULL) {
2309 release_set_methods_jmethod_ids(NULL);
2310 FreeHeap(jmeths);
2311 }
2312
2313 // Release dependencies.
2314 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2315 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2316 // context can contain live dependencies, since there's a race between nmethod &
2317 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2318 // dependencies aren't removed from the context associated with the class (see
2319 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2320 // live dependencies pointing to unloaded nmethods and causes a crash in
2321 // DC::remove_all_dependents() when it touches unloaded nmethod.
2322 dependencies().wipe();
2323
2324 #if INCLUDE_JVMTI
2325 // Deallocate breakpoint records
2326 if (breakpoints() != 0x0) {
2327 methods_do(clear_all_breakpoints);
2328 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2329 }
2330
2331 // deallocate the cached class file
2332 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2333 os::free(_cached_class_file);
2334 _cached_class_file = NULL;
2335 }
2336 #endif
2337
2338 // Decrement symbol reference counts associated with the unloaded class.
2339 if (_name != NULL) _name->decrement_refcount();
2340 // unreference array name derived from this class name (arrays of an unloaded
2341 // class can't be referenced anymore).
2342 if (_array_name != NULL) _array_name->decrement_refcount();
2343 if (_value_types != NULL) {
2344 for (int i = 0; i < _value_types->length(); i++) {
2345 Symbol* s = _value_types->at(i)._class_name;
2346 if (s != NULL) {
2347 s->decrement_refcount();
2348 }
2349 }
2350 }
2351 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2352 }
2353
2354 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2355 if (array == NULL) {
2356 _source_debug_extension = NULL;
2357 } else {
2358 // Adding one to the attribute length in order to store a null terminator
2359 // character could cause an overflow because the attribute length is
2360 // already coded with an u4 in the classfile, but in practice, it's
2361 // unlikely to happen.
2362 assert((length+1) > length, "Overflow checking");
2363 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2364 for (int i = 0; i < length; i++) {
2365 sde[i] = array[i];
2366 }
2367 sde[length] = '\0';
2368 _source_debug_extension = sde;
2369 }
2370 }
2371
2372 address InstanceKlass::static_field_addr(int offset) {
2373 assert(offset >= InstanceMirrorKlass::offset_of_static_fields(), "has already been adjusted");
2374 return (address)(offset + cast_from_oop<intptr_t>(java_mirror()));
2375 }
2376
2377
2378 const char* InstanceKlass::signature_name() const {
2379 int hash_len = 0;
2380 char hash_buf[40];
2381
2382 // If this is an anonymous class, append a hash to make the name unique
2383 if (is_anonymous()) {
2384 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2385 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2386 hash_len = (int)strlen(hash_buf);
2387 }
2388
2389 // Get the internal name as a c string
2390 const char* src = (const char*) (name()->as_C_string());
2391 const int src_length = (int)strlen(src);
2392
2393 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2394
2395 // Add L as type indicator
2396 int dest_index = 0;
2397 dest[dest_index++] = 'L';
2398
2399 // Add the actual class name
2400 for (int src_index = 0; src_index < src_length; ) {
2401 dest[dest_index++] = src[src_index++];
2402 }
2403
2404 // If we have a hash, append it
2405 for (int hash_index = 0; hash_index < hash_len; ) {
2406 dest[dest_index++] = hash_buf[hash_index++];
2407 }
2408
2409 // Add the semicolon and the NULL
2410 dest[dest_index++] = ';';
2411 dest[dest_index] = '\0';
2412 return dest;
2413 }
2414
2415 // Used to obtain the package name from a fully qualified class name.
2416 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2417 if (name == NULL) {
2418 return NULL;
2419 } else {
2420 if (name->utf8_length() <= 0) {
2421 return NULL;
2422 }
2423 ResourceMark rm;
2424 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2425 if (package_name == NULL) {
2426 return NULL;
2427 }
2428 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2429 return pkg_name;
2430 }
2431 }
2432
2433 ModuleEntry* InstanceKlass::module() const {
2434 if (!in_unnamed_package()) {
2435 return _package_entry->module();
2436 }
2437 const Klass* host = host_klass();
2438 if (host == NULL) {
2439 return class_loader_data()->unnamed_module();
2440 }
2441 return host->class_loader_data()->unnamed_module();
2442 }
2443
2444 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2445
2446 // ensure java/ packages only loaded by boot or platform builtin loaders
2447 Handle class_loader(THREAD, loader_data->class_loader());
2448 check_prohibited_package(name(), class_loader, CHECK);
2449
2450 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2451
2452 if (pkg_name != NULL && loader_data != NULL) {
2453
2454 // Find in class loader's package entry table.
2455 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2456
2457 // If the package name is not found in the loader's package
2458 // entry table, it is an indication that the package has not
2459 // been defined. Consider it defined within the unnamed module.
2460 if (_package_entry == NULL) {
2461 ResourceMark rm;
2462
2463 if (!ModuleEntryTable::javabase_defined()) {
2464 // Before java.base is defined during bootstrapping, define all packages in
2465 // the java.base module. If a non-java.base package is erroneously placed
2466 // in the java.base module it will be caught later when java.base
2467 // is defined by ModuleEntryTable::verify_javabase_packages check.
2468 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2469 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2470 } else {
2471 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2472 _package_entry = loader_data->packages()->lookup(pkg_name,
2473 loader_data->unnamed_module());
2474 }
2475
2476 // A package should have been successfully created
2477 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2478 name()->as_C_string(), loader_data->loader_name());
2479 }
2480
2481 if (log_is_enabled(Debug, module)) {
2482 ResourceMark rm;
2483 ModuleEntry* m = _package_entry->module();
2484 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2485 external_name(),
2486 pkg_name->as_C_string(),
2487 loader_data->loader_name(),
2488 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2489 }
2490 } else {
2491 ResourceMark rm;
2492 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2493 external_name(),
2494 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2495 UNNAMED_MODULE);
2496 }
2497 }
2498
2499
2500 // different versions of is_same_class_package
2501
2502 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2503 oop classloader1 = this->class_loader();
2504 PackageEntry* classpkg1 = this->package();
2505 if (class2->is_objArray_klass()) {
2506 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2507 }
2508
2509 oop classloader2;
2510 PackageEntry* classpkg2;
2511 if (class2->is_instance_klass()) {
2512 classloader2 = class2->class_loader();
2513 classpkg2 = class2->package();
2514 } else {
2515 assert(class2->is_typeArray_klass(), "should be type array");
2516 classloader2 = NULL;
2517 classpkg2 = NULL;
2518 }
2519
2520 // Same package is determined by comparing class loader
2521 // and package entries. Both must be the same. This rule
2522 // applies even to classes that are defined in the unnamed
2523 // package, they still must have the same class loader.
2524 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2525 return true;
2526 }
2527
2528 return false;
2529 }
2530
2531 // return true if this class and other_class are in the same package. Classloader
2532 // and classname information is enough to determine a class's package
2533 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2534 const Symbol* other_class_name) const {
2535 if (class_loader() != other_class_loader) {
2536 return false;
2537 }
2538 if (name()->fast_compare(other_class_name) == 0) {
2539 return true;
2540 }
2541
2542 {
2543 ResourceMark rm;
2544
2545 bool bad_class_name = false;
2546 const char* other_pkg =
2547 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2548 if (bad_class_name) {
2549 return false;
2550 }
2551 // Check that package_from_name() returns NULL, not "", if there is no package.
2552 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2553
2554 const Symbol* const this_package_name =
2555 this->package() != NULL ? this->package()->name() : NULL;
2556
2557 if (this_package_name == NULL || other_pkg == NULL) {
2558 // One of the two doesn't have a package. Only return true if the other
2559 // one also doesn't have a package.
2560 return (const char*)this_package_name == other_pkg;
2561 }
2562
2563 // Check if package is identical
2564 return this_package_name->equals(other_pkg);
2565 }
2566 }
2567
2568 // Returns true iff super_method can be overridden by a method in targetclassname
2569 // See JLS 3rd edition 8.4.6.1
2570 // Assumes name-signature match
2571 // "this" is InstanceKlass of super_method which must exist
2572 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2573 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2574 // Private methods can not be overridden
2575 if (super_method->is_private()) {
2576 return false;
2577 }
2578 // If super method is accessible, then override
2579 if ((super_method->is_protected()) ||
2580 (super_method->is_public())) {
2581 return true;
2582 }
2583 // Package-private methods are not inherited outside of package
2584 assert(super_method->is_package_private(), "must be package private");
2585 return(is_same_class_package(targetclassloader(), targetclassname));
2586 }
2587
2588 // Only boot and platform class loaders can define classes in "java/" packages.
2589 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2590 Handle class_loader,
2591 TRAPS) {
2592 if (!class_loader.is_null() &&
2593 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2594 class_name != NULL) {
2595 ResourceMark rm(THREAD);
2596 char* name = class_name->as_C_string();
2597 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2598 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2599 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2600 name = pkg_name->as_C_string();
2601 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2602 StringUtils::replace_no_expand(name, "/", ".");
2603 const char* msg_text1 = "Class loader (instance of): ";
2604 const char* msg_text2 = " tried to load prohibited package name: ";
2605 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2606 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2607 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2608 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2609 }
2610 }
2611 return;
2612 }
2613
2614 // tell if two classes have the same enclosing class (at package level)
2615 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2616 if (class2 == this) return true;
2617 if (!class2->is_instance_klass()) return false;
2618
2619 // must be in same package before we try anything else
2620 if (!is_same_class_package(class2))
2621 return false;
2622
2623 // As long as there is an outer_this.getEnclosingClass,
2624 // shift the search outward.
2625 const InstanceKlass* outer_this = this;
2626 for (;;) {
2627 // As we walk along, look for equalities between outer_this and class2.
2628 // Eventually, the walks will terminate as outer_this stops
2629 // at the top-level class around the original class.
2630 bool ignore_inner_is_member;
2631 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2632 CHECK_false);
2633 if (next == NULL) break;
2634 if (next == class2) return true;
2635 outer_this = InstanceKlass::cast(next);
2636 }
2637
2638 // Now do the same for class2.
2639 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2640 for (;;) {
2641 bool ignore_inner_is_member;
2642 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2643 CHECK_false);
2644 if (next == NULL) break;
2645 // Might as well check the new outer against all available values.
2646 if (next == this) return true;
2647 if (next == outer_this) return true;
2648 outer2 = InstanceKlass::cast(next);
2649 }
2650
2651 // If by this point we have not found an equality between the
2652 // two classes, we know they are in separate package members.
2653 return false;
2654 }
2655
2656 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2657 constantPoolHandle i_cp(THREAD, constants());
2658 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2659 int ioff = iter.inner_class_info_index();
2660 if (ioff != 0) {
2661 // Check to see if the name matches the class we're looking for
2662 // before attempting to find the class.
2663 if (i_cp->klass_name_at_matches(this, ioff)) {
2664 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2665 if (this == inner_klass) {
2666 *ooff = iter.outer_class_info_index();
2667 *noff = iter.inner_name_index();
2668 return true;
2669 }
2670 }
2671 }
2672 }
2673 return false;
2674 }
2675
2676 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2677 InstanceKlass* outer_klass = NULL;
2678 *inner_is_member = false;
2679 int ooff = 0, noff = 0;
2680 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2681 if (has_inner_classes_attr) {
2682 constantPoolHandle i_cp(THREAD, constants());
2683 if (ooff != 0) {
2684 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2685 outer_klass = InstanceKlass::cast(ok);
2686 *inner_is_member = true;
2687 }
2688 if (NULL == outer_klass) {
2689 // It may be anonymous; try for that.
2690 int encl_method_class_idx = enclosing_method_class_index();
2691 if (encl_method_class_idx != 0) {
2692 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2693 outer_klass = InstanceKlass::cast(ok);
2694 *inner_is_member = false;
2695 }
2696 }
2697 }
2698
2699 // If no inner class attribute found for this class.
2700 if (NULL == outer_klass) return NULL;
2701
2702 // Throws an exception if outer klass has not declared k as an inner klass
2703 // We need evidence that each klass knows about the other, or else
2704 // the system could allow a spoof of an inner class to gain access rights.
2705 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2706 return outer_klass;
2707 }
2708
2709 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2710 jint access = access_flags().as_int();
2711
2712 // But check if it happens to be member class.
2713 InnerClassesIterator iter(this);
2714 for (; !iter.done(); iter.next()) {
2715 int ioff = iter.inner_class_info_index();
2716 // Inner class attribute can be zero, skip it.
2717 // Strange but true: JVM spec. allows null inner class refs.
2718 if (ioff == 0) continue;
2719
2720 // only look at classes that are already loaded
2721 // since we are looking for the flags for our self.
2722 Symbol* inner_name = constants()->klass_name_at(ioff);
2723 if (name() == inner_name) {
2724 // This is really a member class.
2725 access = iter.inner_access_flags();
2726 break;
2727 }
2728 }
2729 // Remember to strip ACC_SUPER bit
2730 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2731 }
2732
2733 jint InstanceKlass::jvmti_class_status() const {
2734 jint result = 0;
2735
2736 if (is_linked()) {
2737 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2738 }
2739
2740 if (is_initialized()) {
2741 assert(is_linked(), "Class status is not consistent");
2742 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2743 }
2744 if (is_in_error_state()) {
2745 result |= JVMTI_CLASS_STATUS_ERROR;
2746 }
2747 return result;
2748 }
2749
2750 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2751 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2752 int method_table_offset_in_words = ioe->offset()/wordSize;
2753 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2754 / itableOffsetEntry::size();
2755
2756 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2757 // If the interface isn't implemented by the receiver class,
2758 // the VM should throw IncompatibleClassChangeError.
2759 if (cnt >= nof_interfaces) {
2760 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2761 }
2762
2763 Klass* ik = ioe->interface_klass();
2764 if (ik == holder) break;
2765 }
2766
2767 itableMethodEntry* ime = ioe->first_method_entry(this);
2768 Method* m = ime[index].method();
2769 if (m == NULL) {
2770 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2771 }
2772 return m;
2773 }
2774
2775
2776 #if INCLUDE_JVMTI
2777 // update default_methods for redefineclasses for methods that are
2778 // not yet in the vtable due to concurrent subclass define and superinterface
2779 // redefinition
2780 // Note: those in the vtable, should have been updated via adjust_method_entries
2781 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2782 // search the default_methods for uses of either obsolete or EMCP methods
2783 if (default_methods() != NULL) {
2784 for (int index = 0; index < default_methods()->length(); index ++) {
2785 Method* old_method = default_methods()->at(index);
2786 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2787 continue; // skip uninteresting entries
2788 }
2789 assert(!old_method->is_deleted(), "default methods may not be deleted");
2790
2791 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2792
2793 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2794 assert(old_method != new_method, "sanity check");
2795
2796 default_methods()->at_put(index, new_method);
2797 if (log_is_enabled(Info, redefine, class, update)) {
2798 ResourceMark rm;
2799 if (!(*trace_name_printed)) {
2800 log_info(redefine, class, update)
2801 ("adjust: klassname=%s default methods from name=%s",
2802 external_name(), old_method->method_holder()->external_name());
2803 *trace_name_printed = true;
2804 }
2805 log_debug(redefine, class, update, vtables)
2806 ("default method update: %s(%s) ",
2807 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2808 }
2809 }
2810 }
2811 }
2812 #endif // INCLUDE_JVMTI
2813
2814 // On-stack replacement stuff
2815 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2816 // only one compilation can be active
2817 {
2818 // This is a short non-blocking critical region, so the no safepoint check is ok.
2819 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2820 assert(n->is_osr_method(), "wrong kind of nmethod");
2821 n->set_osr_link(osr_nmethods_head());
2822 set_osr_nmethods_head(n);
2823 // Raise the highest osr level if necessary
2824 if (TieredCompilation) {
2825 Method* m = n->method();
2826 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2827 }
2828 }
2829
2830 // Get rid of the osr methods for the same bci that have lower levels.
2831 if (TieredCompilation) {
2832 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2833 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2834 if (inv != NULL && inv->is_in_use()) {
2835 inv->make_not_entrant();
2836 }
2837 }
2838 }
2839 }
2840
2841 // Remove osr nmethod from the list. Return true if found and removed.
2842 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2843 // This is a short non-blocking critical region, so the no safepoint check is ok.
2844 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2845 assert(n->is_osr_method(), "wrong kind of nmethod");
2846 nmethod* last = NULL;
2847 nmethod* cur = osr_nmethods_head();
2848 int max_level = CompLevel_none; // Find the max comp level excluding n
2849 Method* m = n->method();
2850 // Search for match
2851 bool found = false;
2852 while(cur != NULL && cur != n) {
2853 if (TieredCompilation && m == cur->method()) {
2854 // Find max level before n
2855 max_level = MAX2(max_level, cur->comp_level());
2856 }
2857 last = cur;
2858 cur = cur->osr_link();
2859 }
2860 nmethod* next = NULL;
2861 if (cur == n) {
2862 found = true;
2863 next = cur->osr_link();
2864 if (last == NULL) {
2865 // Remove first element
2866 set_osr_nmethods_head(next);
2867 } else {
2868 last->set_osr_link(next);
2869 }
2870 }
2871 n->set_osr_link(NULL);
2872 if (TieredCompilation) {
2873 cur = next;
2874 while (cur != NULL) {
2875 // Find max level after n
2876 if (m == cur->method()) {
2877 max_level = MAX2(max_level, cur->comp_level());
2878 }
2879 cur = cur->osr_link();
2880 }
2881 m->set_highest_osr_comp_level(max_level);
2882 }
2883 return found;
2884 }
2885
2886 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2887 // This is a short non-blocking critical region, so the no safepoint check is ok.
2888 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2889 nmethod* osr = osr_nmethods_head();
2890 int found = 0;
2891 while (osr != NULL) {
2892 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2893 if (osr->method() == m) {
2894 osr->mark_for_deoptimization();
2895 found++;
2896 }
2897 osr = osr->osr_link();
2898 }
2899 return found;
2900 }
2901
2902 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2903 // This is a short non-blocking critical region, so the no safepoint check is ok.
2904 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2905 nmethod* osr = osr_nmethods_head();
2906 nmethod* best = NULL;
2907 while (osr != NULL) {
2908 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2909 // There can be a time when a c1 osr method exists but we are waiting
2910 // for a c2 version. When c2 completes its osr nmethod we will trash
2911 // the c1 version and only be able to find the c2 version. However
2912 // while we overflow in the c1 code at back branches we don't want to
2913 // try and switch to the same code as we are already running
2914
2915 if (osr->method() == m &&
2916 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2917 if (match_level) {
2918 if (osr->comp_level() == comp_level) {
2919 // Found a match - return it.
2920 return osr;
2921 }
2922 } else {
2923 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2924 if (osr->comp_level() == CompLevel_highest_tier) {
2925 // Found the best possible - return it.
2926 return osr;
2927 }
2928 best = osr;
2929 }
2930 }
2931 }
2932 osr = osr->osr_link();
2933 }
2934 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2935 return best;
2936 }
2937 return NULL;
2938 }
2939
2940 // -----------------------------------------------------------------------------------------------------
2941 // Printing
2942
2943 #ifndef PRODUCT
2944
2945 #define BULLET " - "
2946
2947 static const char* state_names[] = {
2948 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2949 };
2950
2951 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
2952 ResourceMark rm;
2953 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
2954 for (int i = 0; i < len; i++) forward_refs[i] = 0;
2955 for (int i = 0; i < len; i++) {
2956 intptr_t e = start[i];
2957 st->print("%d : " INTPTR_FORMAT, i, e);
2958 if (forward_refs[i] != 0) {
2959 int from = forward_refs[i];
2960 int off = (int) start[from];
2961 st->print(" (offset %d <= [%d])", off, from);
2962 }
2963 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2964 st->print(" ");
2965 ((Metadata*)e)->print_value_on(st);
2966 } else if (self != NULL && e > 0 && e < 0x10000) {
2967 address location = self + e;
2968 int index = (int)((intptr_t*)location - start);
2969 st->print(" (offset %d => [%d])", (int)e, index);
2970 if (index >= 0 && index < len)
2971 forward_refs[index] = i;
2972 }
2973 st->cr();
2974 }
2975 }
2976
2977 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2978 return print_vtable(NULL, reinterpret_cast<intptr_t*>(start), len, st);
2979 }
2980
2981 template<typename T>
2982 static void print_array_on(outputStream* st, Array<T>* 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 : ", i); array->at(i)->print_value_on(st); st->cr();
2988 }
2989 }
2990 }
2991
2992 static void print_array_on(outputStream* st, Array<int>* array) {
2993 if (array == NULL) { st->print_cr("NULL"); return; }
2994 array->print_value_on(st); st->cr();
2995 if (Verbose || WizardMode) {
2996 for (int i = 0; i < array->length(); i++) {
2997 st->print("%d : %d", i, array->at(i)); st->cr();
2998 }
2999 }
3000 }
3001
3002 void InstanceKlass::print_on(outputStream* st) const {
3003 assert(is_klass(), "must be klass");
3004 Klass::print_on(st);
3005
3006 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3007 st->print(BULLET"klass size: %d", size()); st->cr();
3008 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3009 st->print(BULLET"misc flags: 0x%x", _misc_flags); st->cr();
3010 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3011 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3012 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3013 st->print(BULLET"sub: ");
3014 Klass* sub = subklass();
3015 int n;
3016 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3017 if (n < MaxSubklassPrintSize) {
3018 sub->print_value_on(st);
3019 st->print(" ");
3020 }
3021 }
3022 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3023 st->cr();
3024
3025 if (is_interface()) {
3026 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3027 if (nof_implementors() == 1) {
3028 st->print_cr(BULLET"implementor: ");
3029 st->print(" ");
3030 implementor()->print_value_on(st);
3031 st->cr();
3032 }
3033 }
3034
3035 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3036 st->print(BULLET"methods: "); print_array_on(st, methods());
3037 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3038 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3039 if (default_vtable_indices() != NULL) {
3040 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3041 }
3042 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3043 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3044 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3045 if (class_loader_data() != NULL) {
3046 st->print(BULLET"class loader data: ");
3047 class_loader_data()->print_value_on(st);
3048 st->cr();
3049 }
3050 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3051 if (source_file_name() != NULL) {
3052 st->print(BULLET"source file: ");
3053 source_file_name()->print_value_on(st);
3054 st->cr();
3055 }
3056 if (source_debug_extension() != NULL) {
3057 st->print(BULLET"source debug extension: ");
3058 st->print("%s", source_debug_extension());
3059 st->cr();
3060 }
3061 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3062 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3063 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3064 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3065 {
3066 bool have_pv = false;
3067 // previous versions are linked together through the InstanceKlass
3068 for (InstanceKlass* pv_node = previous_versions();
3069 pv_node != NULL;
3070 pv_node = pv_node->previous_versions()) {
3071 if (!have_pv)
3072 st->print(BULLET"previous version: ");
3073 have_pv = true;
3074 pv_node->constants()->print_value_on(st);
3075 }
3076 if (have_pv) st->cr();
3077 }
3078
3079 if (generic_signature() != NULL) {
3080 st->print(BULLET"generic signature: ");
3081 generic_signature()->print_value_on(st);
3082 st->cr();
3083 }
3084 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3085 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3086 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3087 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3088 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3089 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(NULL, start_of_itable(), itable_length(), st);
3090 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3091 FieldPrinter print_static_field(st);
3092 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3093 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3094 FieldPrinter print_nonstatic_field(st);
3095 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3096 ik->do_nonstatic_fields(&print_nonstatic_field);
3097
3098 st->print(BULLET"non-static oop maps: ");
3099 OopMapBlock* map = start_of_nonstatic_oop_maps();
3100 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3101 while (map < end_map) {
3102 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3103 map++;
3104 }
3105 st->cr();
3106 }
3107
3108 #endif //PRODUCT
3109
3110 void InstanceKlass::print_value_on(outputStream* st) const {
3111 assert(is_klass(), "must be klass");
3112 if (Verbose || WizardMode) access_flags().print_on(st);
3113 name()->print_value_on(st);
3114 }
3115
3116 #ifndef PRODUCT
3117
3118 void FieldPrinter::do_field(fieldDescriptor* fd) {
3119 _st->print(BULLET);
3120 if (_obj == NULL) {
3121 fd->print_on(_st);
3122 _st->cr();
3123 } else {
3124 fd->print_on_for(_st, _obj);
3125 _st->cr();
3126 }
3127 }
3128
3129
3130 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3131 Klass::oop_print_on(obj, st);
3132
3133 if (this == SystemDictionary::String_klass()) {
3134 typeArrayOop value = java_lang_String::value(obj);
3135 juint length = java_lang_String::length(obj);
3136 if (value != NULL &&
3137 value->is_typeArray() &&
3138 length <= (juint) value->length()) {
3139 st->print(BULLET"string: ");
3140 java_lang_String::print(obj, st);
3141 st->cr();
3142 if (!WizardMode) return; // that is enough
3143 }
3144 }
3145
3146 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3147 FieldPrinter print_field(st, obj);
3148 do_nonstatic_fields(&print_field);
3149
3150 if (this == SystemDictionary::Class_klass()) {
3151 st->print(BULLET"signature: ");
3152 java_lang_Class::print_signature(obj, st);
3153 st->cr();
3154 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3155 st->print(BULLET"fake entry for mirror: ");
3156 mirrored_klass->print_value_on_maybe_null(st);
3157 st->cr();
3158 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3159 st->print(BULLET"fake entry for array: ");
3160 array_klass->print_value_on_maybe_null(st);
3161 st->cr();
3162 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3163 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3164 Klass* real_klass = java_lang_Class::as_Klass(obj);
3165 if (real_klass != NULL && real_klass->is_instance_klass()) {
3166 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3167 }
3168 } else if (this == SystemDictionary::MethodType_klass()) {
3169 st->print(BULLET"signature: ");
3170 java_lang_invoke_MethodType::print_signature(obj, st);
3171 st->cr();
3172 }
3173 }
3174
3175 #endif //PRODUCT
3176
3177 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3178 st->print("a ");
3179 name()->print_value_on(st);
3180 obj->print_address_on(st);
3181 if (this == SystemDictionary::String_klass()
3182 && java_lang_String::value(obj) != NULL) {
3183 ResourceMark rm;
3184 int len = java_lang_String::length(obj);
3185 int plen = (len < 24 ? len : 12);
3186 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3187 st->print(" = \"%s\"", str);
3188 if (len > plen)
3189 st->print("...[%d]", len);
3190 } else if (this == SystemDictionary::Class_klass()) {
3191 Klass* k = java_lang_Class::as_Klass(obj);
3192 st->print(" = ");
3193 if (k != NULL) {
3194 k->print_value_on(st);
3195 } else {
3196 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3197 st->print("%s", tname ? tname : "type?");
3198 }
3199 } else if (this == SystemDictionary::MethodType_klass()) {
3200 st->print(" = ");
3201 java_lang_invoke_MethodType::print_signature(obj, st);
3202 } else if (java_lang_boxing_object::is_instance(obj)) {
3203 st->print(" = ");
3204 java_lang_boxing_object::print(obj, st);
3205 } else if (this == SystemDictionary::LambdaForm_klass()) {
3206 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3207 if (vmentry != NULL) {
3208 st->print(" => ");
3209 vmentry->print_value_on(st);
3210 }
3211 } else if (this == SystemDictionary::MemberName_klass()) {
3212 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3213 if (vmtarget != NULL) {
3214 st->print(" = ");
3215 vmtarget->print_value_on(st);
3216 } else {
3217 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3218 st->print(".");
3219 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3220 }
3221 }
3222 }
3223
3224 const char* InstanceKlass::internal_name() const {
3225 return external_name();
3226 }
3227
3228 bool InstanceKlass::is_declared_value_type(int index) {
3229 assert(constants()->is_within_bounds(index) &&
3230 constants()->tag_at(index).is_klass_or_reference(), "Invalid index");
3231 return InstanceKlass::is_declared_value_type(value_types(), index);
3232 }
3233
3234 bool InstanceKlass::is_declared_value_type(Array<ValueTypes>* value_types, int index) {
3235 if (value_types == NULL) return false; // No ValueType attribute in this class file
3236 for(int i = 0; i < value_types->length(); i++) {
3237 if (value_types->at(i)._class_info_index == index) {
3238 return true;
3239 }
3240 }
3241 return false;
3242 }
3243
3244 bool InstanceKlass::is_declared_value_type(Symbol* symbol) {
3245 return InstanceKlass::is_declared_value_type(constants(), value_types(), symbol);
3246 }
3247
3248 bool InstanceKlass::is_declared_value_type(ConstantPool* constants, Array<ValueTypes>* value_types, Symbol* symbol) {
3249 assert(symbol != NULL, "Sanity check");
3250 if (value_types == NULL) return false; // No ValueType attribute in this class file
3251 for(int i = 0; i < value_types->length(); i++) {
3252 if (value_types->at(i)._class_name == symbol) {
3253 return true;
3254 }
3255 }
3256 // symbol not found, class name symbol might not have been
3257 // updated yet
3258 for(int i = 0; i < value_types->length(); i++) {
3259 if (constants->klass_at_noresolve((int)value_types->at(i)._class_info_index) == symbol) {
3260 value_types->adr_at(i)->_class_name = symbol;
3261 symbol->increment_refcount();
3262 return true;
3263 }
3264 }
3265 return false;
3266 }
3267
3268 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3269 const char* module_name,
3270 const ClassFileStream* cfs) const {
3271 if (!log_is_enabled(Info, class, load)) {
3272 return;
3273 }
3274
3275 ResourceMark rm;
3276 LogMessage(class, load) msg;
3277 stringStream info_stream;
3278
3279 // Name and class hierarchy info
3280 info_stream.print("%s", external_name());
3281
3282 // Source
3283 if (cfs != NULL) {
3284 if (cfs->source() != NULL) {
3285 if (module_name != NULL) {
3286 if (ClassLoader::is_modules_image(cfs->source())) {
3287 info_stream.print(" source: jrt:/%s", module_name);
3288 } else {
3289 info_stream.print(" source: %s", cfs->source());
3290 }
3291 } else {
3292 info_stream.print(" source: %s", cfs->source());
3293 }
3294 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3295 Thread* THREAD = Thread::current();
3296 Klass* caller =
3297 THREAD->is_Java_thread()
3298 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3299 : NULL;
3300 // caller can be NULL, for example, during a JVMTI VM_Init hook
3301 if (caller != NULL) {
3302 info_stream.print(" source: instance of %s", caller->external_name());
3303 } else {
3304 // source is unknown
3305 }
3306 } else {
3307 oop class_loader = loader_data->class_loader();
3308 info_stream.print(" source: %s", class_loader->klass()->external_name());
3309 }
3310 } else {
3311 info_stream.print(" source: shared objects file");
3312 }
3313
3314 msg.info("%s", info_stream.as_string());
3315
3316 if (log_is_enabled(Debug, class, load)) {
3317 stringStream debug_stream;
3318
3319 // Class hierarchy info
3320 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3321 p2i(this), p2i(superklass()));
3322
3323 // Interfaces
3324 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3325 debug_stream.print(" interfaces:");
3326 int length = local_interfaces()->length();
3327 for (int i = 0; i < length; i++) {
3328 debug_stream.print(" " INTPTR_FORMAT,
3329 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3330 }
3331 }
3332
3333 // Class loader
3334 debug_stream.print(" loader: [");
3335 loader_data->print_value_on(&debug_stream);
3336 debug_stream.print("]");
3337
3338 // Classfile checksum
3339 if (cfs) {
3340 debug_stream.print(" bytes: %d checksum: %08x",
3341 cfs->length(),
3342 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3343 cfs->length()));
3344 }
3345
3346 msg.debug("%s", debug_stream.as_string());
3347 }
3348 }
3349
3350 #if INCLUDE_SERVICES
3351 // Size Statistics
3352 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3353 Klass::collect_statistics(sz);
3354
3355 sz->_inst_size = wordSize * size_helper();
3356 sz->_vtab_bytes = wordSize * vtable_length();
3357 sz->_itab_bytes = wordSize * itable_length();
3358 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3359
3360 int n = 0;
3361 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3362 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3363 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3364 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3365 n += (sz->_fields_bytes = sz->count_array(fields()));
3366 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3367 sz->_ro_bytes += n;
3368
3369 const ConstantPool* cp = constants();
3370 if (cp) {
3371 cp->collect_statistics(sz);
3372 }
3373
3374 const Annotations* anno = annotations();
3375 if (anno) {
3376 anno->collect_statistics(sz);
3377 }
3378
3379 const Array<Method*>* methods_array = methods();
3380 if (methods()) {
3381 for (int i = 0; i < methods_array->length(); i++) {
3382 Method* method = methods_array->at(i);
3383 if (method) {
3384 sz->_method_count ++;
3385 method->collect_statistics(sz);
3386 }
3387 }
3388 }
3389 }
3390 #endif // INCLUDE_SERVICES
3391
3392 // Verification
3393
3394 class VerifyFieldClosure: public OopClosure {
3395 protected:
3396 template <class T> void do_oop_work(T* p) {
3397 oop obj = oopDesc::load_decode_heap_oop(p);
3398 if (!oopDesc::is_oop_or_null(obj)) {
3399 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3400 Universe::print_on(tty);
3401 guarantee(false, "boom");
3402 }
3403 }
3404 public:
3405 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3406 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3407 };
3408
3409 void InstanceKlass::verify_on(outputStream* st) {
3410 #ifndef PRODUCT
3411 // Avoid redundant verifies, this really should be in product.
3412 if (_verify_count == Universe::verify_count()) return;
3413 _verify_count = Universe::verify_count();
3414 #endif
3415
3416 // Verify Klass
3417 Klass::verify_on(st);
3418
3419 // Verify that klass is present in ClassLoaderData
3420 guarantee(class_loader_data()->contains_klass(this),
3421 "this class isn't found in class loader data");
3422
3423 // Verify vtables
3424 if (is_linked()) {
3425 // $$$ This used to be done only for m/s collections. Doing it
3426 // always seemed a valid generalization. (DLD -- 6/00)
3427 vtable().verify(st);
3428 }
3429
3430 // Verify first subklass
3431 if (subklass() != NULL) {
3432 guarantee(subklass()->is_klass(), "should be klass");
3433 }
3434
3435 // Verify siblings
3436 Klass* super = this->super();
3437 Klass* sib = next_sibling();
3438 if (sib != NULL) {
3439 if (sib == this) {
3440 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3441 }
3442
3443 guarantee(sib->is_klass(), "should be klass");
3444 guarantee(sib->super() == super, "siblings should have same superklass");
3445 }
3446
3447 // Verify implementor fields
3448 Klass* im = implementor();
3449 if (im != NULL) {
3450 guarantee(is_interface(), "only interfaces should have implementor set");
3451 guarantee(im->is_klass(), "should be klass");
3452 guarantee(!im->is_interface() || im == this,
3453 "implementors cannot be interfaces");
3454 }
3455
3456 // Verify local interfaces
3457 if (local_interfaces()) {
3458 Array<Klass*>* local_interfaces = this->local_interfaces();
3459 for (int j = 0; j < local_interfaces->length(); j++) {
3460 Klass* e = local_interfaces->at(j);
3461 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3462 }
3463 }
3464
3465 // Verify transitive interfaces
3466 if (transitive_interfaces() != NULL) {
3467 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3468 for (int j = 0; j < transitive_interfaces->length(); j++) {
3469 Klass* e = transitive_interfaces->at(j);
3470 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3471 }
3472 }
3473
3474 // Verify methods
3475 if (methods() != NULL) {
3476 Array<Method*>* methods = this->methods();
3477 for (int j = 0; j < methods->length(); j++) {
3478 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3479 }
3480 for (int j = 0; j < methods->length() - 1; j++) {
3481 Method* m1 = methods->at(j);
3482 Method* m2 = methods->at(j + 1);
3483 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3484 }
3485 }
3486
3487 // Verify method ordering
3488 if (method_ordering() != NULL) {
3489 Array<int>* method_ordering = this->method_ordering();
3490 int length = method_ordering->length();
3491 if (JvmtiExport::can_maintain_original_method_order() ||
3492 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3493 guarantee(length == methods()->length(), "invalid method ordering length");
3494 jlong sum = 0;
3495 for (int j = 0; j < length; j++) {
3496 int original_index = method_ordering->at(j);
3497 guarantee(original_index >= 0, "invalid method ordering index");
3498 guarantee(original_index < length, "invalid method ordering index");
3499 sum += original_index;
3500 }
3501 // Verify sum of indices 0,1,...,length-1
3502 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3503 } else {
3504 guarantee(length == 0, "invalid method ordering length");
3505 }
3506 }
3507
3508 // Verify default methods
3509 if (default_methods() != NULL) {
3510 Array<Method*>* methods = this->default_methods();
3511 for (int j = 0; j < methods->length(); j++) {
3512 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3513 }
3514 for (int j = 0; j < methods->length() - 1; j++) {
3515 Method* m1 = methods->at(j);
3516 Method* m2 = methods->at(j + 1);
3517 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3518 }
3519 }
3520
3521 // Verify JNI static field identifiers
3522 if (jni_ids() != NULL) {
3523 jni_ids()->verify(this);
3524 }
3525
3526 // Verify other fields
3527 if (array_klasses() != NULL) {
3528 guarantee(array_klasses()->is_klass(), "should be klass");
3529 }
3530 if (constants() != NULL) {
3531 guarantee(constants()->is_constantPool(), "should be constant pool");
3532 }
3533 const Klass* host = host_klass();
3534 if (host != NULL) {
3535 guarantee(host->is_klass(), "should be klass");
3536 }
3537 }
3538
3539 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3540 Klass::oop_verify_on(obj, st);
3541 VerifyFieldClosure blk;
3542 obj->oop_iterate_no_header(&blk);
3543 }
3544
3545
3546 // JNIid class for jfieldIDs only
3547 // Note to reviewers:
3548 // These JNI functions are just moved over to column 1 and not changed
3549 // in the compressed oops workspace.
3550 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3551 _holder = holder;
3552 _offset = offset;
3553 _next = next;
3554 debug_only(_is_static_field_id = false;)
3555 }
3556
3557
3558 JNIid* JNIid::find(int offset) {
3559 JNIid* current = this;
3560 while (current != NULL) {
3561 if (current->offset() == offset) return current;
3562 current = current->next();
3563 }
3564 return NULL;
3565 }
3566
3567 void JNIid::deallocate(JNIid* current) {
3568 while (current != NULL) {
3569 JNIid* next = current->next();
3570 delete current;
3571 current = next;
3572 }
3573 }
3574
3575
3576 void JNIid::verify(Klass* holder) {
3577 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3578 int end_field_offset;
3579 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3580
3581 JNIid* current = this;
3582 while (current != NULL) {
3583 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3584 #ifdef ASSERT
3585 int o = current->offset();
3586 if (current->is_static_field_id()) {
3587 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3588 }
3589 #endif
3590 current = current->next();
3591 }
3592 }
3593
3594 oop InstanceKlass::klass_holder_phantom() {
3595 oop* addr;
3596 if (is_anonymous()) {
3597 addr = _java_mirror.ptr_raw();
3598 } else {
3599 addr = &class_loader_data()->_class_loader;
3600 }
3601 return RootAccess<IN_CONCURRENT_ROOT | ON_PHANTOM_OOP_REF>::oop_load(addr);
3602 }
3603
3604 #ifdef ASSERT
3605 void InstanceKlass::set_init_state(ClassState state) {
3606 bool good_state = is_shared() ? (_init_state <= state)
3607 : (_init_state < state);
3608 assert(good_state || state == allocated, "illegal state transition");
3609 _init_state = (u1)state;
3610 }
3611 #endif
3612
3613 #if INCLUDE_JVMTI
3614
3615 // RedefineClasses() support for previous versions
3616
3617 // Globally, there is at least one previous version of a class to walk
3618 // during class unloading, which is saved because old methods in the class
3619 // are still running. Otherwise the previous version list is cleaned up.
3620 bool InstanceKlass::_has_previous_versions = false;
3621
3622 // Returns true if there are previous versions of a class for class
3623 // unloading only. Also resets the flag to false. purge_previous_version
3624 // will set the flag to true if there are any left, i.e., if there's any
3625 // work to do for next time. This is to avoid the expensive code cache
3626 // walk in CLDG::do_unloading().
3627 bool InstanceKlass::has_previous_versions_and_reset() {
3628 bool ret = _has_previous_versions;
3629 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3630 ret ? "true" : "false");
3631 _has_previous_versions = false;
3632 return ret;
3633 }
3634
3635 // Purge previous versions before adding new previous versions of the class and
3636 // during class unloading.
3637 void InstanceKlass::purge_previous_version_list() {
3638 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3639 assert(has_been_redefined(), "Should only be called for main class");
3640
3641 // Quick exit.
3642 if (previous_versions() == NULL) {
3643 return;
3644 }
3645
3646 // This klass has previous versions so see what we can cleanup
3647 // while it is safe to do so.
3648
3649 int deleted_count = 0; // leave debugging breadcrumbs
3650 int live_count = 0;
3651 ClassLoaderData* loader_data = class_loader_data();
3652 assert(loader_data != NULL, "should never be null");
3653
3654 ResourceMark rm;
3655 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3656
3657 // previous versions are linked together through the InstanceKlass
3658 InstanceKlass* pv_node = previous_versions();
3659 InstanceKlass* last = this;
3660 int version = 0;
3661
3662 // check the previous versions list
3663 for (; pv_node != NULL; ) {
3664
3665 ConstantPool* pvcp = pv_node->constants();
3666 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3667
3668 if (!pvcp->on_stack()) {
3669 // If the constant pool isn't on stack, none of the methods
3670 // are executing. Unlink this previous_version.
3671 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3672 // so will be deallocated during the next phase of class unloading.
3673 log_trace(redefine, class, iklass, purge)
3674 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3675 // For debugging purposes.
3676 pv_node->set_is_scratch_class();
3677 // Unlink from previous version list.
3678 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3679 InstanceKlass* next = pv_node->previous_versions();
3680 pv_node->link_previous_versions(NULL); // point next to NULL
3681 last->link_previous_versions(next);
3682 // Add to the deallocate list after unlinking
3683 loader_data->add_to_deallocate_list(pv_node);
3684 pv_node = next;
3685 deleted_count++;
3686 version++;
3687 continue;
3688 } else {
3689 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3690 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3691 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3692 live_count++;
3693 // found a previous version for next time we do class unloading
3694 _has_previous_versions = true;
3695 }
3696
3697 // At least one method is live in this previous version.
3698 // Reset dead EMCP methods not to get breakpoints.
3699 // All methods are deallocated when all of the methods for this class are no
3700 // longer running.
3701 Array<Method*>* method_refs = pv_node->methods();
3702 if (method_refs != NULL) {
3703 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3704 for (int j = 0; j < method_refs->length(); j++) {
3705 Method* method = method_refs->at(j);
3706
3707 if (!method->on_stack()) {
3708 // no breakpoints for non-running methods
3709 if (method->is_running_emcp()) {
3710 method->set_running_emcp(false);
3711 }
3712 } else {
3713 assert (method->is_obsolete() || method->is_running_emcp(),
3714 "emcp method cannot run after emcp bit is cleared");
3715 log_trace(redefine, class, iklass, purge)
3716 ("purge: %s(%s): prev method @%d in version @%d is alive",
3717 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3718 }
3719 }
3720 }
3721 // next previous version
3722 last = pv_node;
3723 pv_node = pv_node->previous_versions();
3724 version++;
3725 }
3726 log_trace(redefine, class, iklass, purge)
3727 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3728 }
3729
3730 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3731 int emcp_method_count) {
3732 int obsolete_method_count = old_methods->length() - emcp_method_count;
3733
3734 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3735 _previous_versions != NULL) {
3736 // We have a mix of obsolete and EMCP methods so we have to
3737 // clear out any matching EMCP method entries the hard way.
3738 int local_count = 0;
3739 for (int i = 0; i < old_methods->length(); i++) {
3740 Method* old_method = old_methods->at(i);
3741 if (old_method->is_obsolete()) {
3742 // only obsolete methods are interesting
3743 Symbol* m_name = old_method->name();
3744 Symbol* m_signature = old_method->signature();
3745
3746 // previous versions are linked together through the InstanceKlass
3747 int j = 0;
3748 for (InstanceKlass* prev_version = _previous_versions;
3749 prev_version != NULL;
3750 prev_version = prev_version->previous_versions(), j++) {
3751
3752 Array<Method*>* method_refs = prev_version->methods();
3753 for (int k = 0; k < method_refs->length(); k++) {
3754 Method* method = method_refs->at(k);
3755
3756 if (!method->is_obsolete() &&
3757 method->name() == m_name &&
3758 method->signature() == m_signature) {
3759 // The current RedefineClasses() call has made all EMCP
3760 // versions of this method obsolete so mark it as obsolete
3761 log_trace(redefine, class, iklass, add)
3762 ("%s(%s): flush obsolete method @%d in version @%d",
3763 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3764
3765 method->set_is_obsolete();
3766 break;
3767 }
3768 }
3769
3770 // The previous loop may not find a matching EMCP method, but
3771 // that doesn't mean that we can optimize and not go any
3772 // further back in the PreviousVersion generations. The EMCP
3773 // method for this generation could have already been made obsolete,
3774 // but there still may be an older EMCP method that has not
3775 // been made obsolete.
3776 }
3777
3778 if (++local_count >= obsolete_method_count) {
3779 // no more obsolete methods so bail out now
3780 break;
3781 }
3782 }
3783 }
3784 }
3785 }
3786
3787 // Save the scratch_class as the previous version if any of the methods are running.
3788 // The previous_versions are used to set breakpoints in EMCP methods and they are
3789 // also used to clean MethodData links to redefined methods that are no longer running.
3790 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3791 int emcp_method_count) {
3792 assert(Thread::current()->is_VM_thread(),
3793 "only VMThread can add previous versions");
3794
3795 ResourceMark rm;
3796 log_trace(redefine, class, iklass, add)
3797 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3798
3799 // Clean out old previous versions for this class
3800 purge_previous_version_list();
3801
3802 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3803 // a previous redefinition may be made obsolete by this redefinition.
3804 Array<Method*>* old_methods = scratch_class->methods();
3805 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3806
3807 // If the constant pool for this previous version of the class
3808 // is not marked as being on the stack, then none of the methods
3809 // in this previous version of the class are on the stack so
3810 // we don't need to add this as a previous version.
3811 ConstantPool* cp_ref = scratch_class->constants();
3812 if (!cp_ref->on_stack()) {
3813 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3814 // For debugging purposes.
3815 scratch_class->set_is_scratch_class();
3816 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3817 return;
3818 }
3819
3820 if (emcp_method_count != 0) {
3821 // At least one method is still running, check for EMCP methods
3822 for (int i = 0; i < old_methods->length(); i++) {
3823 Method* old_method = old_methods->at(i);
3824 if (!old_method->is_obsolete() && old_method->on_stack()) {
3825 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3826 // we can add breakpoints for it.
3827
3828 // We set the method->on_stack bit during safepoints for class redefinition
3829 // and use this bit to set the is_running_emcp bit.
3830 // After the safepoint, the on_stack bit is cleared and the running emcp
3831 // method may exit. If so, we would set a breakpoint in a method that
3832 // is never reached, but this won't be noticeable to the programmer.
3833 old_method->set_running_emcp(true);
3834 log_trace(redefine, class, iklass, add)
3835 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3836 } else if (!old_method->is_obsolete()) {
3837 log_trace(redefine, class, iklass, add)
3838 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3839 }
3840 }
3841 }
3842
3843 // Add previous version if any methods are still running.
3844 // Set has_previous_version flag for processing during class unloading.
3845 _has_previous_versions = true;
3846 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3847 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3848 scratch_class->link_previous_versions(previous_versions());
3849 link_previous_versions(scratch_class);
3850 } // end add_previous_version()
3851
3852 #endif // INCLUDE_JVMTI
3853
3854 Method* InstanceKlass::method_with_idnum(int idnum) {
3855 Method* m = NULL;
3856 if (idnum < methods()->length()) {
3857 m = methods()->at(idnum);
3858 }
3859 if (m == NULL || m->method_idnum() != idnum) {
3860 for (int index = 0; index < methods()->length(); ++index) {
3861 m = methods()->at(index);
3862 if (m->method_idnum() == idnum) {
3863 return m;
3864 }
3865 }
3866 // None found, return null for the caller to handle.
3867 return NULL;
3868 }
3869 return m;
3870 }
3871
3872
3873 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3874 if (idnum >= methods()->length()) {
3875 return NULL;
3876 }
3877 Method* m = methods()->at(idnum);
3878 if (m != NULL && m->orig_method_idnum() == idnum) {
3879 return m;
3880 }
3881 // Obsolete method idnum does not match the original idnum
3882 for (int index = 0; index < methods()->length(); ++index) {
3883 m = methods()->at(index);
3884 if (m->orig_method_idnum() == idnum) {
3885 return m;
3886 }
3887 }
3888 // None found, return null for the caller to handle.
3889 return NULL;
3890 }
3891
3892
3893 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3894 InstanceKlass* holder = get_klass_version(version);
3895 if (holder == NULL) {
3896 return NULL; // The version of klass is gone, no method is found
3897 }
3898 Method* method = holder->method_with_orig_idnum(idnum);
3899 return method;
3900 }
3901
3902 #if INCLUDE_JVMTI
3903 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3904 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3905 // Ignore the archived class stream data
3906 return NULL;
3907 } else {
3908 return _cached_class_file;
3909 }
3910 }
3911
3912 jint InstanceKlass::get_cached_class_file_len() {
3913 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3914 }
3915
3916 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3917 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3918 }
3919
3920 #if INCLUDE_CDS
3921 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3922 if (DumpSharedSpaces) {
3923 return _cached_class_file;
3924 } else {
3925 assert(this->is_shared(), "class should be shared");
3926 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3927 return _cached_class_file;
3928 } else {
3929 return NULL;
3930 }
3931 }
3932 }
3933 #endif
3934 #endif
3935
3936 #define THROW_DVT_ERROR(s) \
3937 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), \
3938 "ValueCapableClass class '%s' %s", external_name(),(s)); \
3939 return