1 /*
2 * Copyright (c) 1997, 2014, 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 "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/verifier.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "gc_implementation/shared/markSweep.inline.hpp"
32 #include "gc_interface/collectedHeap.inline.hpp"
33 #include "interpreter/oopMapCache.hpp"
34 #include "interpreter/rewriter.hpp"
35 #include "jvmtifiles/jvmti.h"
36 #include "memory/genOopClosures.inline.hpp"
37 #include "memory/heapInspection.hpp"
38 #include "memory/iterator.inline.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/oopFactory.hpp"
41 #include "oops/fieldStreams.hpp"
42 #include "oops/instanceClassLoaderKlass.hpp"
43 #include "oops/instanceKlass.inline.hpp"
44 #include "oops/instanceMirrorKlass.hpp"
45 #include "oops/instanceOop.hpp"
46 #include "oops/klass.inline.hpp"
47 #include "oops/method.hpp"
48 #include "oops/oop.inline.hpp"
49 #include "oops/symbol.hpp"
50 #include "prims/jvmtiExport.hpp"
51 #include "prims/jvmtiRedefineClassesTrace.hpp"
52 #include "prims/jvmtiRedefineClasses.hpp"
53 #include "prims/jvmtiThreadState.hpp"
54 #include "prims/methodComparator.hpp"
55 #include "runtime/atomic.inline.hpp"
56 #include "runtime/fieldDescriptor.hpp"
57 #include "runtime/handles.inline.hpp"
58 #include "runtime/javaCalls.hpp"
59 #include "runtime/mutexLocker.hpp"
60 #include "runtime/orderAccess.inline.hpp"
61 #include "runtime/thread.inline.hpp"
62 #include "services/classLoadingService.hpp"
63 #include "services/threadService.hpp"
64 #include "utilities/dtrace.hpp"
65 #include "utilities/macros.hpp"
66 #if INCLUDE_ALL_GCS
67 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
68 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
69 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
70 #include "gc_implementation/g1/g1RemSet.inline.hpp"
71 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
72 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
73 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
74 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
75 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
76 #include "oops/oop.pcgc.inline.hpp"
77 #endif // INCLUDE_ALL_GCS
78 #ifdef COMPILER1
79 #include "c1/c1_Compiler.hpp"
80 #endif
81
82 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
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, clss, thread_type) \
96 { \
97 char* data = NULL; \
98 int len = 0; \
99 Symbol* name = (clss)->name(); \
100 if (name != NULL) { \
101 data = (char*)name->bytes(); \
102 len = name->utf8_length(); \
103 } \
104 HOTSPOT_CLASS_INITIALIZATION_##type( \
105 data, len, (clss)->class_loader(), thread_type); \
106 }
107
108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
109 { \
110 char* data = NULL; \
111 int len = 0; \
112 Symbol* name = (clss)->name(); \
113 if (name != NULL) { \
114 data = (char*)name->bytes(); \
115 len = name->utf8_length(); \
116 } \
117 HOTSPOT_CLASS_INITIALIZATION_##type( \
118 data, len, (clss)->class_loader(), thread_type, wait); \
119 }
120
121 #else // ndef DTRACE_ENABLED
122
123 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
125
126 #endif // ndef DTRACE_ENABLED
127
128 volatile int InstanceKlass::_total_instanceKlass_count = 0;
129
130 InstanceKlass* InstanceKlass::allocate_instance_klass(
131 ClassLoaderData* loader_data,
132 int vtable_len,
133 int itable_len,
134 int static_field_size,
135 int nonstatic_oop_map_size,
136 ReferenceType rt,
137 AccessFlags access_flags,
138 Symbol* name,
139 Klass* super_klass,
140 bool is_anonymous,
141 TRAPS) {
142
143 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
144 access_flags.is_interface(), is_anonymous);
145
146 // Allocation
147 InstanceKlass* ik;
148 if (rt == REF_NONE) {
149 if (name == vmSymbols::java_lang_Class()) {
150 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
151 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
152 access_flags, is_anonymous);
153 } else if (name == vmSymbols::java_lang_ClassLoader() ||
154 (SystemDictionary::ClassLoader_klass_loaded() &&
155 super_klass != NULL &&
156 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
157 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
158 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
159 access_flags, is_anonymous);
160 } else {
161 // normal class
162 ik = new (loader_data, size, THREAD) InstanceKlass(
163 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
164 access_flags, is_anonymous);
165 }
166 } else {
167 // reference klass
168 ik = new (loader_data, size, THREAD) InstanceRefKlass(
169 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
170 access_flags, is_anonymous);
171 }
172
173 // Check for pending exception before adding to the loader data and incrementing
174 // class count. Can get OOM here.
175 if (HAS_PENDING_EXCEPTION) {
176 return NULL;
177 }
178
179 // Add all classes to our internal class loader list here,
180 // including classes in the bootstrap (NULL) class loader.
181 loader_data->add_class(ik);
182
183 Atomic::inc(&_total_instanceKlass_count);
184 return ik;
185 }
186
187
188 // copy method ordering from resource area to Metaspace
189 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
190 if (m != NULL) {
191 // allocate a new array and copy contents (memcpy?)
192 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
193 for (int i = 0; i < m->length(); i++) {
194 _method_ordering->at_put(i, m->at(i));
195 }
196 } else {
197 _method_ordering = Universe::the_empty_int_array();
198 }
199 }
200
201 // create a new array of vtable_indices for default methods
202 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
203 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
204 assert(default_vtable_indices() == NULL, "only create once");
205 set_default_vtable_indices(vtable_indices);
206 return vtable_indices;
207 }
208
209 InstanceKlass::InstanceKlass(int vtable_len,
210 int itable_len,
211 int static_field_size,
212 int nonstatic_oop_map_size,
213 ReferenceType rt,
214 AccessFlags access_flags,
215 bool is_anonymous,
216 DispatchTag tag)
217 : Klass(tag) {
218 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
219
220 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
221 access_flags.is_interface(), is_anonymous);
222
223 set_vtable_length(vtable_len);
224 set_itable_length(itable_len);
225 set_static_field_size(static_field_size);
226 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
227 set_access_flags(access_flags);
228 _misc_flags = 0; // initialize to zero
229 set_is_anonymous(is_anonymous);
230 assert(size() == iksize, "wrong size for object");
231
232 set_array_klasses(NULL);
233 set_methods(NULL);
234 set_method_ordering(NULL);
235 set_default_methods(NULL);
236 set_default_vtable_indices(NULL);
237 set_local_interfaces(NULL);
238 set_transitive_interfaces(NULL);
239 init_implementor();
240 set_fields(NULL, 0);
241 set_constants(NULL);
242 set_class_loader_data(NULL);
243 set_source_file_name_index(0);
244 set_source_debug_extension(NULL, 0);
245 set_array_name(NULL);
246 set_inner_classes(NULL);
247 set_static_oop_field_count(0);
248 set_nonstatic_field_size(0);
249 set_is_marked_dependent(false);
250 set_has_unloaded_dependent(false);
251 set_init_state(InstanceKlass::allocated);
252 set_init_thread(NULL);
253 set_reference_type(rt);
254 set_oop_map_cache(NULL);
255 set_jni_ids(NULL);
256 set_osr_nmethods_head(NULL);
257 set_breakpoints(NULL);
258 init_previous_versions();
259 set_generic_signature_index(0);
260 release_set_methods_jmethod_ids(NULL);
261 set_annotations(NULL);
262 set_jvmti_cached_class_field_map(NULL);
263 set_initial_method_idnum(0);
264 _dependencies = NULL;
265 set_jvmti_cached_class_field_map(NULL);
266 set_cached_class_file(NULL);
267 set_initial_method_idnum(0);
268 set_minor_version(0);
269 set_major_version(0);
270 NOT_PRODUCT(_verify_count = 0;)
271
272 // initialize the non-header words to zero
273 intptr_t* p = (intptr_t*)this;
274 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
275 p[index] = NULL_WORD;
276 }
277
278 // Set temporary value until parseClassFile updates it with the real instance
279 // size.
280 set_layout_helper(Klass::instance_layout_helper(0, true));
281 }
282
283
284 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
285 Array<Method*>* methods) {
286 if (methods != NULL && methods != Universe::the_empty_method_array() &&
287 !methods->is_shared()) {
288 for (int i = 0; i < methods->length(); i++) {
289 Method* method = methods->at(i);
290 if (method == NULL) continue; // maybe null if error processing
291 // Only want to delete methods that are not executing for RedefineClasses.
292 // The previous version will point to them so they're not totally dangling
293 assert (!method->on_stack(), "shouldn't be called with methods on stack");
294 MetadataFactory::free_metadata(loader_data, method);
295 }
296 MetadataFactory::free_array<Method*>(loader_data, methods);
297 }
298 }
299
300 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
301 Klass* super_klass,
302 Array<Klass*>* local_interfaces,
303 Array<Klass*>* transitive_interfaces) {
304 // Only deallocate transitive interfaces if not empty, same as super class
305 // or same as local interfaces. See code in parseClassFile.
306 Array<Klass*>* ti = transitive_interfaces;
307 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
308 // check that the interfaces don't come from super class
309 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
310 InstanceKlass::cast(super_klass)->transitive_interfaces();
311 if (ti != sti && ti != NULL && !ti->is_shared()) {
312 MetadataFactory::free_array<Klass*>(loader_data, ti);
313 }
314 }
315
316 // local interfaces can be empty
317 if (local_interfaces != Universe::the_empty_klass_array() &&
318 local_interfaces != NULL && !local_interfaces->is_shared()) {
319 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
320 }
321 }
322
323 // This function deallocates the metadata and C heap pointers that the
324 // InstanceKlass points to.
325 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
326
327 // Orphan the mirror first, CMS thinks it's still live.
328 if (java_mirror() != NULL) {
329 java_lang_Class::set_klass(java_mirror(), NULL);
330 }
331
332 // Need to take this class off the class loader data list.
333 loader_data->remove_class(this);
334
335 // The array_klass for this class is created later, after error handling.
336 // For class redefinition, we keep the original class so this scratch class
337 // doesn't have an array class. Either way, assert that there is nothing
338 // to deallocate.
339 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
340
341 // Release C heap allocated data that this might point to, which includes
342 // reference counting symbol names.
343 release_C_heap_structures();
344
345 deallocate_methods(loader_data, methods());
346 set_methods(NULL);
347
348 if (method_ordering() != NULL &&
349 method_ordering() != Universe::the_empty_int_array() &&
350 !method_ordering()->is_shared()) {
351 MetadataFactory::free_array<int>(loader_data, method_ordering());
352 }
353 set_method_ordering(NULL);
354
355 // default methods can be empty
356 if (default_methods() != NULL &&
357 default_methods() != Universe::the_empty_method_array() &&
358 !default_methods()->is_shared()) {
359 MetadataFactory::free_array<Method*>(loader_data, default_methods());
360 }
361 // Do NOT deallocate the default methods, they are owned by superinterfaces.
362 set_default_methods(NULL);
363
364 // default methods vtable indices can be empty
365 if (default_vtable_indices() != NULL &&
366 !default_vtable_indices()->is_shared()) {
367 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
368 }
369 set_default_vtable_indices(NULL);
370
371
372 // This array is in Klass, but remove it with the InstanceKlass since
373 // this place would be the only caller and it can share memory with transitive
374 // interfaces.
375 if (secondary_supers() != NULL &&
376 secondary_supers() != Universe::the_empty_klass_array() &&
377 secondary_supers() != transitive_interfaces() &&
378 !secondary_supers()->is_shared()) {
379 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
380 }
381 set_secondary_supers(NULL);
382
383 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
384 set_transitive_interfaces(NULL);
385 set_local_interfaces(NULL);
386
387 if (fields() != NULL && !fields()->is_shared()) {
388 MetadataFactory::free_array<jushort>(loader_data, fields());
389 }
390 set_fields(NULL, 0);
391
392 // If a method from a redefined class is using this constant pool, don't
393 // delete it, yet. The new class's previous version will point to this.
394 if (constants() != NULL) {
395 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
396 if (!constants()->is_shared()) {
397 MetadataFactory::free_metadata(loader_data, constants());
398 }
399 set_constants(NULL);
400 }
401
402 if (inner_classes() != NULL &&
403 inner_classes() != Universe::the_empty_short_array() &&
404 !inner_classes()->is_shared()) {
405 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
406 }
407 set_inner_classes(NULL);
408
409 // We should deallocate the Annotations instance if it's not in shared spaces.
410 if (annotations() != NULL && !annotations()->is_shared()) {
411 MetadataFactory::free_metadata(loader_data, annotations());
412 }
413 set_annotations(NULL);
414 }
415
416 bool InstanceKlass::should_be_initialized() const {
417 return !is_initialized();
418 }
419
420 klassVtable* InstanceKlass::vtable() const {
421 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
422 }
423
424 klassItable* InstanceKlass::itable() const {
425 return new klassItable(instanceKlassHandle(this));
426 }
427
428 void InstanceKlass::eager_initialize(Thread *thread) {
429 if (!EagerInitialization) return;
430
431 if (this->is_not_initialized()) {
432 // abort if the the class has a class initializer
433 if (this->class_initializer() != NULL) return;
434
435 // abort if it is java.lang.Object (initialization is handled in genesis)
436 Klass* super = this->super();
437 if (super == NULL) return;
438
439 // abort if the super class should be initialized
440 if (!InstanceKlass::cast(super)->is_initialized()) return;
441
442 // call body to expose the this pointer
443 instanceKlassHandle this_k(thread, this);
444 eager_initialize_impl(this_k);
445 }
446 }
447
448 // JVMTI spec thinks there are signers and protection domain in the
449 // instanceKlass. These accessors pretend these fields are there.
450 // The hprof specification also thinks these fields are in InstanceKlass.
451 oop InstanceKlass::protection_domain() const {
452 // return the protection_domain from the mirror
453 return java_lang_Class::protection_domain(java_mirror());
454 }
455
456 // To remove these from requires an incompatible change and CCC request.
457 objArrayOop InstanceKlass::signers() const {
458 // return the signers from the mirror
459 return java_lang_Class::signers(java_mirror());
460 }
461
462 oop InstanceKlass::init_lock() const {
463 // return the init lock from the mirror
464 oop lock = java_lang_Class::init_lock(java_mirror());
465 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
466 "only fully initialized state can have a null lock");
467 return lock;
468 }
469
470 // Set the initialization lock to null so the object can be GC'ed. Any racing
471 // threads to get this lock will see a null lock and will not lock.
472 // That's okay because they all check for initialized state after getting
473 // the lock and return.
474 void InstanceKlass::fence_and_clear_init_lock() {
475 // make sure previous stores are all done, notably the init_state.
476 OrderAccess::storestore();
477 java_lang_Class::set_init_lock(java_mirror(), NULL);
478 assert(!is_not_initialized(), "class must be initialized now");
479 }
480
481 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
482 EXCEPTION_MARK;
483 oop init_lock = this_k->init_lock();
484 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
485
486 // abort if someone beat us to the initialization
487 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized()
488
489 ClassState old_state = this_k->init_state();
490 link_class_impl(this_k, 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 != this_k->_init_state )
499 this_k->set_init_state (old_state);
500 } else {
501 // linking successfull, mark class as initialized
502 this_k->set_init_state (fully_initialized);
503 this_k->fence_and_clear_init_lock();
504 // trace
505 if (TraceClassInitialization) {
506 ResourceMark rm(THREAD);
507 tty->print_cr("[Initialized %s without side effects]", this_k->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 HandleMark hm(THREAD);
519 instanceKlassHandle this_k(THREAD, this);
520 initialize_impl(this_k, CHECK);
521 // Note: at this point the class may be initialized
522 // OR it may be in the state of being initialized
523 // in case of recursive initialization!
524 } else {
525 assert(is_initialized(), "sanity check");
526 }
527 }
528
529
530 bool InstanceKlass::verify_code(
531 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
532 // 1) Verify the bytecodes
533 Verifier::Mode mode =
534 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
535 return Verifier::verify(this_k, mode, this_k->should_verify_class(), CHECK_false);
536 }
537
538
539 // Used exclusively by the shared spaces dump mechanism to prevent
540 // classes mapped into the shared regions in new VMs from appearing linked.
541
542 void InstanceKlass::unlink_class() {
543 assert(is_linked(), "must be linked");
544 _init_state = loaded;
545 }
546
547 void InstanceKlass::link_class(TRAPS) {
548 assert(is_loaded(), "must be loaded");
549 if (!is_linked()) {
550 HandleMark hm(THREAD);
551 instanceKlassHandle this_k(THREAD, this);
552 link_class_impl(this_k, true, CHECK);
553 }
554 }
555
556 // Called to verify that a class can link during initialization, without
557 // throwing a VerifyError.
558 bool InstanceKlass::link_class_or_fail(TRAPS) {
559 assert(is_loaded(), "must be loaded");
560 if (!is_linked()) {
561 HandleMark hm(THREAD);
562 instanceKlassHandle this_k(THREAD, this);
563 link_class_impl(this_k, false, CHECK_false);
564 }
565 return is_linked();
566 }
567
568 bool InstanceKlass::link_class_impl(
569 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
570 // check for error state
571 if (this_k->is_in_error_state()) {
572 ResourceMark rm(THREAD);
573 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
574 this_k->external_name(), false);
575 }
576 // return if already verified
577 if (this_k->is_linked()) {
578 return true;
579 }
580
581 // Timing
582 // timer handles recursion
583 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
584 JavaThread* jt = (JavaThread*)THREAD;
585
586 // link super class before linking this class
587 instanceKlassHandle super(THREAD, this_k->super());
588 if (super.not_null()) {
589 if (super->is_interface()) { // check if super class is an interface
590 ResourceMark rm(THREAD);
591 Exceptions::fthrow(
592 THREAD_AND_LOCATION,
593 vmSymbols::java_lang_IncompatibleClassChangeError(),
594 "class %s has interface %s as super class",
595 this_k->external_name(),
596 super->external_name()
597 );
598 return false;
599 }
600
601 link_class_impl(super, throw_verifyerror, CHECK_false);
602 }
603
604 // link all interfaces implemented by this class before linking this class
605 Array<Klass*>* interfaces = this_k->local_interfaces();
606 int num_interfaces = interfaces->length();
607 for (int index = 0; index < num_interfaces; index++) {
608 HandleMark hm(THREAD);
609 instanceKlassHandle ih(THREAD, interfaces->at(index));
610 link_class_impl(ih, throw_verifyerror, CHECK_false);
611 }
612
613 // in case the class is linked in the process of linking its superclasses
614 if (this_k->is_linked()) {
615 return true;
616 }
617
618 // trace only the link time for this klass that includes
619 // the verification time
620 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
621 ClassLoader::perf_class_link_selftime(),
622 ClassLoader::perf_classes_linked(),
623 jt->get_thread_stat()->perf_recursion_counts_addr(),
624 jt->get_thread_stat()->perf_timers_addr(),
625 PerfClassTraceTime::CLASS_LINK);
626
627 // verification & rewriting
628 {
629 oop init_lock = this_k->init_lock();
630 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
631 // rewritten will have been set if loader constraint error found
632 // on an earlier link attempt
633 // don't verify or rewrite if already rewritten
634
635 if (!this_k->is_linked()) {
636 if (!this_k->is_rewritten()) {
637 {
638 // Timer includes any side effects of class verification (resolution,
639 // etc), but not recursive entry into verify_code().
640 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
641 ClassLoader::perf_class_verify_selftime(),
642 ClassLoader::perf_classes_verified(),
643 jt->get_thread_stat()->perf_recursion_counts_addr(),
644 jt->get_thread_stat()->perf_timers_addr(),
645 PerfClassTraceTime::CLASS_VERIFY);
646 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
647 if (!verify_ok) {
648 return false;
649 }
650 }
651
652 // Just in case a side-effect of verify linked this class already
653 // (which can sometimes happen since the verifier loads classes
654 // using custom class loaders, which are free to initialize things)
655 if (this_k->is_linked()) {
656 return true;
657 }
658
659 // also sets rewritten
660 this_k->rewrite_class(CHECK_false);
661 }
662
663 // relocate jsrs and link methods after they are all rewritten
664 this_k->link_methods(CHECK_false);
665
666 // Initialize the vtable and interface table after
667 // methods have been rewritten since rewrite may
668 // fabricate new Method*s.
669 // also does loader constraint checking
670 if (!this_k()->is_shared()) {
671 ResourceMark rm(THREAD);
672 this_k->vtable()->initialize_vtable(true, CHECK_false);
673 this_k->itable()->initialize_itable(true, CHECK_false);
674 }
675 #ifdef ASSERT
676 else {
677 ResourceMark rm(THREAD);
678 this_k->vtable()->verify(tty, true);
679 // In case itable verification is ever added.
680 // this_k->itable()->verify(tty, true);
681 }
682 #endif
683 this_k->set_init_state(linked);
684 if (JvmtiExport::should_post_class_prepare()) {
685 Thread *thread = THREAD;
686 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
687 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
688 }
689 }
690 }
691 return true;
692 }
693
694
695 // Rewrite the byte codes of all of the methods of a class.
696 // The rewriter must be called exactly once. Rewriting must happen after
697 // verification but before the first method of the class is executed.
698 void InstanceKlass::rewrite_class(TRAPS) {
699 assert(is_loaded(), "must be loaded");
700 instanceKlassHandle this_k(THREAD, this);
701 if (this_k->is_rewritten()) {
702 assert(this_k()->is_shared(), "rewriting an unshared class?");
703 return;
704 }
705 Rewriter::rewrite(this_k, CHECK);
706 this_k->set_rewritten();
707 }
708
709 // Now relocate and link method entry points after class is rewritten.
710 // This is outside is_rewritten flag. In case of an exception, it can be
711 // executed more than once.
712 void InstanceKlass::link_methods(TRAPS) {
713 int len = methods()->length();
714 for (int i = len-1; i >= 0; i--) {
715 methodHandle m(THREAD, methods()->at(i));
716
717 // Set up method entry points for compiler and interpreter .
718 m->link_method(m, CHECK);
719
720 // This is for JVMTI and unrelated to relocator but the last thing we do
721 #ifdef ASSERT
722 if (StressMethodComparator) {
723 ResourceMark rm(THREAD);
724 static int nmc = 0;
725 for (int j = i; j >= 0 && j >= i-4; j--) {
726 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
727 bool z = MethodComparator::methods_EMCP(m(),
728 methods()->at(j));
729 if (j == i && !z) {
730 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
731 assert(z, "method must compare equal to itself");
732 }
733 }
734 }
735 #endif //ASSERT
736 }
737 }
738
739
740 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
741 // Make sure klass is linked (verified) before initialization
742 // A class could already be verified, since it has been reflected upon.
743 this_k->link_class(CHECK);
744
745 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_k()), -1);
746
747 bool wait = false;
748
749 // refer to the JVM book page 47 for description of steps
750 // Step 1
751 {
752 oop init_lock = this_k->init_lock();
753 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
754
755 Thread *self = THREAD; // it's passed the current thread
756
757 // Step 2
758 // If we were to use wait() instead of waitInterruptibly() then
759 // we might end up throwing IE from link/symbol resolution sites
760 // that aren't expected to throw. This would wreak havoc. See 6320309.
761 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
762 wait = true;
763 ol.waitUninterruptibly(CHECK);
764 }
765
766 // Step 3
767 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
768 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_k()), -1,wait);
769 return;
770 }
771
772 // Step 4
773 if (this_k->is_initialized()) {
774 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_k()), -1,wait);
775 return;
776 }
777
778 // Step 5
779 if (this_k->is_in_error_state()) {
780 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_k()), -1,wait);
781 ResourceMark rm(THREAD);
782 const char* desc = "Could not initialize class ";
783 const char* className = this_k->external_name();
784 size_t msglen = strlen(desc) + strlen(className) + 1;
785 char* message = NEW_RESOURCE_ARRAY(char, msglen);
786 if (NULL == message) {
787 // Out of memory: can't create detailed error message
788 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
789 } else {
790 jio_snprintf(message, msglen, "%s%s", desc, className);
791 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
792 }
793 }
794
795 // Step 6
796 this_k->set_init_state(being_initialized);
797 this_k->set_init_thread(self);
798 }
799
800 // Step 7
801 Klass* super_klass = this_k->super();
802 if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) {
803 super_klass->initialize(THREAD);
804
805 if (HAS_PENDING_EXCEPTION) {
806 Handle e(THREAD, PENDING_EXCEPTION);
807 CLEAR_PENDING_EXCEPTION;
808 {
809 EXCEPTION_MARK;
810 this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
811 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
812 }
813 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_k()), -1,wait);
814 THROW_OOP(e());
815 }
816 }
817
818 if (this_k->has_default_methods()) {
819 // Step 7.5: initialize any interfaces which have default methods
820 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
821 Klass* iface = this_k->local_interfaces()->at(i);
822 InstanceKlass* ik = InstanceKlass::cast(iface);
823 if (ik->has_default_methods() && ik->should_be_initialized()) {
824 ik->initialize(THREAD);
825
826 if (HAS_PENDING_EXCEPTION) {
827 Handle e(THREAD, PENDING_EXCEPTION);
828 CLEAR_PENDING_EXCEPTION;
829 {
830 EXCEPTION_MARK;
831 // Locks object, set state, and notify all waiting threads
832 this_k->set_initialization_state_and_notify(
833 initialization_error, THREAD);
834
835 // ignore any exception thrown, superclass initialization error is
836 // thrown below
837 CLEAR_PENDING_EXCEPTION;
838 }
839 DTRACE_CLASSINIT_PROBE_WAIT(
840 super__failed, InstanceKlass::cast(this_k()), -1, wait);
841 THROW_OOP(e());
842 }
843 }
844 }
845 }
846
847 // Step 8
848 {
849 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
850 JavaThread* jt = (JavaThread*)THREAD;
851 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_k()), -1,wait);
852 // Timer includes any side effects of class initialization (resolution,
853 // etc), but not recursive entry into call_class_initializer().
854 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
855 ClassLoader::perf_class_init_selftime(),
856 ClassLoader::perf_classes_inited(),
857 jt->get_thread_stat()->perf_recursion_counts_addr(),
858 jt->get_thread_stat()->perf_timers_addr(),
859 PerfClassTraceTime::CLASS_CLINIT);
860 this_k->call_class_initializer(THREAD);
861 }
862
863 // Step 9
864 if (!HAS_PENDING_EXCEPTION) {
865 this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
866 { ResourceMark rm(THREAD);
867 debug_only(this_k->vtable()->verify(tty, true);)
868 }
869 }
870 else {
871 // Step 10 and 11
872 Handle e(THREAD, PENDING_EXCEPTION);
873 CLEAR_PENDING_EXCEPTION;
874 // JVMTI has already reported the pending exception
875 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
876 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
877 {
878 EXCEPTION_MARK;
879 this_k->set_initialization_state_and_notify(initialization_error, THREAD);
880 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
881 // JVMTI has already reported the pending exception
882 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
883 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
884 }
885 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_k()), -1,wait);
886 if (e->is_a(SystemDictionary::Error_klass())) {
887 THROW_OOP(e());
888 } else {
889 JavaCallArguments args(e);
890 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
891 vmSymbols::throwable_void_signature(),
892 &args);
893 }
894 }
895 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_k()), -1,wait);
896 }
897
898
899 // Note: implementation moved to static method to expose the this pointer.
900 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
901 instanceKlassHandle kh(THREAD, this);
902 set_initialization_state_and_notify_impl(kh, state, CHECK);
903 }
904
905 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
906 oop init_lock = this_k->init_lock();
907 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
908 this_k->set_init_state(state);
909 this_k->fence_and_clear_init_lock();
910 ol.notify_all(CHECK);
911 }
912
913 // The embedded _implementor field can only record one implementor.
914 // When there are more than one implementors, the _implementor field
915 // is set to the interface Klass* itself. Following are the possible
916 // values for the _implementor field:
917 // NULL - no implementor
918 // implementor Klass* - one implementor
919 // self - more than one implementor
920 //
921 // The _implementor field only exists for interfaces.
922 void InstanceKlass::add_implementor(Klass* k) {
923 assert(Compile_lock->owned_by_self(), "");
924 assert(is_interface(), "not interface");
925 // Filter out my subinterfaces.
926 // (Note: Interfaces are never on the subklass list.)
927 if (InstanceKlass::cast(k)->is_interface()) return;
928
929 // Filter out subclasses whose supers already implement me.
930 // (Note: CHA must walk subclasses of direct implementors
931 // in order to locate indirect implementors.)
932 Klass* sk = InstanceKlass::cast(k)->super();
933 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
934 // We only need to check one immediate superclass, since the
935 // implements_interface query looks at transitive_interfaces.
936 // Any supers of the super have the same (or fewer) transitive_interfaces.
937 return;
938
939 Klass* ik = implementor();
940 if (ik == NULL) {
941 set_implementor(k);
942 } else if (ik != this) {
943 // There is already an implementor. Use itself as an indicator of
944 // more than one implementors.
945 set_implementor(this);
946 }
947
948 // The implementor also implements the transitive_interfaces
949 for (int index = 0; index < local_interfaces()->length(); index++) {
950 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
951 }
952 }
953
954 void InstanceKlass::init_implementor() {
955 if (is_interface()) {
956 set_implementor(NULL);
957 }
958 }
959
960
961 void InstanceKlass::process_interfaces(Thread *thread) {
962 // link this class into the implementors list of every interface it implements
963 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
964 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
965 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
966 assert(interf->is_interface(), "expected interface");
967 interf->add_implementor(this);
968 }
969 }
970
971 bool InstanceKlass::can_be_primary_super_slow() const {
972 if (is_interface())
973 return false;
974 else
975 return Klass::can_be_primary_super_slow();
976 }
977
978 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
979 // The secondaries are the implemented interfaces.
980 InstanceKlass* ik = InstanceKlass::cast(this);
981 Array<Klass*>* interfaces = ik->transitive_interfaces();
982 int num_secondaries = num_extra_slots + interfaces->length();
983 if (num_secondaries == 0) {
984 // Must share this for correct bootstrapping!
985 set_secondary_supers(Universe::the_empty_klass_array());
986 return NULL;
987 } else if (num_extra_slots == 0) {
988 // The secondary super list is exactly the same as the transitive interfaces.
989 // Redefine classes has to be careful not to delete this!
990 set_secondary_supers(interfaces);
991 return NULL;
992 } else {
993 // Copy transitive interfaces to a temporary growable array to be constructed
994 // into the secondary super list with extra slots.
995 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
996 for (int i = 0; i < interfaces->length(); i++) {
997 secondaries->push(interfaces->at(i));
998 }
999 return secondaries;
1000 }
1001 }
1002
1003 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1004 if (k->is_interface()) {
1005 return implements_interface(k);
1006 } else {
1007 return Klass::compute_is_subtype_of(k);
1008 }
1009 }
1010
1011 bool InstanceKlass::implements_interface(Klass* k) const {
1012 if (this == k) return true;
1013 assert(k->is_interface(), "should be an interface class");
1014 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1015 if (transitive_interfaces()->at(i) == k) {
1016 return true;
1017 }
1018 }
1019 return false;
1020 }
1021
1022 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1023 // Verify direct super interface
1024 if (this == k) return true;
1025 assert(k->is_interface(), "should be an interface class");
1026 for (int i = 0; i < local_interfaces()->length(); i++) {
1027 if (local_interfaces()->at(i) == k) {
1028 return true;
1029 }
1030 }
1031 return false;
1032 }
1033
1034 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1035 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1036 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1037 report_java_out_of_memory("Requested array size exceeds VM limit");
1038 JvmtiExport::post_array_size_exhausted();
1039 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1040 }
1041 int size = objArrayOopDesc::object_size(length);
1042 Klass* ak = array_klass(n, CHECK_NULL);
1043 KlassHandle h_ak (THREAD, ak);
1044 objArrayOop o =
1045 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1046 return o;
1047 }
1048
1049 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1050 if (TraceFinalizerRegistration) {
1051 tty->print("Registered ");
1052 i->print_value_on(tty);
1053 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
1054 }
1055 instanceHandle h_i(THREAD, i);
1056 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1057 JavaValue result(T_VOID);
1058 JavaCallArguments args(h_i);
1059 methodHandle mh (THREAD, Universe::finalizer_register_method());
1060 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1061 return h_i();
1062 }
1063
1064 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1065 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1066 int size = size_helper(); // Query before forming handle.
1067
1068 KlassHandle h_k(THREAD, this);
1069
1070 instanceOop i;
1071
1072 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1073 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1074 i = register_finalizer(i, CHECK_NULL);
1075 }
1076 return i;
1077 }
1078
1079 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1080 if (is_interface() || is_abstract()) {
1081 ResourceMark rm(THREAD);
1082 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1083 : vmSymbols::java_lang_InstantiationException(), external_name());
1084 }
1085 if (this == SystemDictionary::Class_klass()) {
1086 ResourceMark rm(THREAD);
1087 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1088 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1089 }
1090 }
1091
1092 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1093 instanceKlassHandle this_k(THREAD, this);
1094 return array_klass_impl(this_k, or_null, n, THREAD);
1095 }
1096
1097 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1098 if (this_k->array_klasses() == NULL) {
1099 if (or_null) return NULL;
1100
1101 ResourceMark rm;
1102 JavaThread *jt = (JavaThread *)THREAD;
1103 {
1104 // Atomic creation of array_klasses
1105 MutexLocker mc(Compile_lock, THREAD); // for vtables
1106 MutexLocker ma(MultiArray_lock, THREAD);
1107
1108 // Check if update has already taken place
1109 if (this_k->array_klasses() == NULL) {
1110 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1111 this_k->set_array_klasses(k);
1112 }
1113 }
1114 }
1115 // _this will always be set at this point
1116 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1117 if (or_null) {
1118 return oak->array_klass_or_null(n);
1119 }
1120 return oak->array_klass(n, CHECK_NULL);
1121 }
1122
1123 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1124 return array_klass_impl(or_null, 1, THREAD);
1125 }
1126
1127 void InstanceKlass::call_class_initializer(TRAPS) {
1128 instanceKlassHandle ik (THREAD, this);
1129 call_class_initializer_impl(ik, THREAD);
1130 }
1131
1132 static int call_class_initializer_impl_counter = 0; // for debugging
1133
1134 Method* InstanceKlass::class_initializer() {
1135 Method* clinit = find_method(
1136 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1137 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1138 return clinit;
1139 }
1140 return NULL;
1141 }
1142
1143 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1144 if (ReplayCompiles &&
1145 (ReplaySuppressInitializers == 1 ||
1146 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1147 // Hide the existence of the initializer for the purpose of replaying the compile
1148 return;
1149 }
1150
1151 methodHandle h_method(THREAD, this_k->class_initializer());
1152 assert(!this_k->is_initialized(), "we cannot initialize twice");
1153 if (TraceClassInitialization) {
1154 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1155 this_k->name()->print_value();
1156 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_k());
1157 }
1158 if (h_method() != NULL) {
1159 JavaCallArguments args; // No arguments
1160 JavaValue result(T_VOID);
1161 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1162 }
1163 }
1164
1165
1166 void InstanceKlass::mask_for(methodHandle method, int bci,
1167 InterpreterOopMap* entry_for) {
1168 // Dirty read, then double-check under a lock.
1169 if (_oop_map_cache == NULL) {
1170 // Otherwise, allocate a new one.
1171 MutexLocker x(OopMapCacheAlloc_lock);
1172 // First time use. Allocate a cache in C heap
1173 if (_oop_map_cache == NULL) {
1174 // Release stores from OopMapCache constructor before assignment
1175 // to _oop_map_cache. C++ compilers on ppc do not emit the
1176 // required memory barrier only because of the volatile
1177 // qualifier of _oop_map_cache.
1178 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1179 }
1180 }
1181 // _oop_map_cache is constant after init; lookup below does is own locking.
1182 _oop_map_cache->lookup(method, bci, entry_for);
1183 }
1184
1185
1186 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1187 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1188 Symbol* f_name = fs.name();
1189 Symbol* f_sig = fs.signature();
1190 if (f_name == name && f_sig == sig) {
1191 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1192 return true;
1193 }
1194 }
1195 return false;
1196 }
1197
1198
1199 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1200 const int n = local_interfaces()->length();
1201 for (int i = 0; i < n; i++) {
1202 Klass* intf1 = local_interfaces()->at(i);
1203 assert(intf1->is_interface(), "just checking type");
1204 // search for field in current interface
1205 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1206 assert(fd->is_static(), "interface field must be static");
1207 return intf1;
1208 }
1209 // search for field in direct superinterfaces
1210 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1211 if (intf2 != NULL) return intf2;
1212 }
1213 // otherwise field lookup fails
1214 return NULL;
1215 }
1216
1217
1218 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1219 // search order according to newest JVM spec (5.4.3.2, p.167).
1220 // 1) search for field in current klass
1221 if (find_local_field(name, sig, fd)) {
1222 return const_cast<InstanceKlass*>(this);
1223 }
1224 // 2) search for field recursively in direct superinterfaces
1225 { Klass* intf = find_interface_field(name, sig, fd);
1226 if (intf != NULL) return intf;
1227 }
1228 // 3) apply field lookup recursively if superclass exists
1229 { Klass* supr = super();
1230 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1231 }
1232 // 4) otherwise field lookup fails
1233 return NULL;
1234 }
1235
1236
1237 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1238 // search order according to newest JVM spec (5.4.3.2, p.167).
1239 // 1) search for field in current klass
1240 if (find_local_field(name, sig, fd)) {
1241 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1242 }
1243 // 2) search for field recursively in direct superinterfaces
1244 if (is_static) {
1245 Klass* intf = find_interface_field(name, sig, fd);
1246 if (intf != NULL) return intf;
1247 }
1248 // 3) apply field lookup recursively if superclass exists
1249 { Klass* supr = super();
1250 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1251 }
1252 // 4) otherwise field lookup fails
1253 return NULL;
1254 }
1255
1256
1257 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1258 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1259 if (fs.offset() == offset) {
1260 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1261 if (fd->is_static() == is_static) return true;
1262 }
1263 }
1264 return false;
1265 }
1266
1267
1268 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1269 Klass* klass = const_cast<InstanceKlass*>(this);
1270 while (klass != NULL) {
1271 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1272 return true;
1273 }
1274 klass = klass->super();
1275 }
1276 return false;
1277 }
1278
1279
1280 void InstanceKlass::methods_do(void f(Method* method)) {
1281 // Methods aren't stable until they are loaded. This can be read outside
1282 // a lock through the ClassLoaderData for profiling
1283 if (!is_loaded()) {
1284 return;
1285 }
1286
1287 int len = methods()->length();
1288 for (int index = 0; index < len; index++) {
1289 Method* m = methods()->at(index);
1290 assert(m->is_method(), "must be method");
1291 f(m);
1292 }
1293 }
1294
1295
1296 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1297 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1298 if (fs.access_flags().is_static()) {
1299 fieldDescriptor& fd = fs.field_descriptor();
1300 cl->do_field(&fd);
1301 }
1302 }
1303 }
1304
1305
1306 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1307 instanceKlassHandle h_this(THREAD, this);
1308 do_local_static_fields_impl(h_this, f, mirror, CHECK);
1309 }
1310
1311
1312 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1313 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1314 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1315 if (fs.access_flags().is_static()) {
1316 fieldDescriptor& fd = fs.field_descriptor();
1317 f(&fd, mirror, CHECK);
1318 }
1319 }
1320 }
1321
1322
1323 static int compare_fields_by_offset(int* a, int* b) {
1324 return a[0] - b[0];
1325 }
1326
1327 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1328 InstanceKlass* super = superklass();
1329 if (super != NULL) {
1330 super->do_nonstatic_fields(cl);
1331 }
1332 fieldDescriptor fd;
1333 int length = java_fields_count();
1334 // In DebugInfo nonstatic fields are sorted by offset.
1335 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1336 int j = 0;
1337 for (int i = 0; i < length; i += 1) {
1338 fd.reinitialize(this, i);
1339 if (!fd.is_static()) {
1340 fields_sorted[j + 0] = fd.offset();
1341 fields_sorted[j + 1] = i;
1342 j += 2;
1343 }
1344 }
1345 if (j > 0) {
1346 length = j;
1347 // _sort_Fn is defined in growableArray.hpp.
1348 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1349 for (int i = 0; i < length; i += 2) {
1350 fd.reinitialize(this, fields_sorted[i + 1]);
1351 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1352 cl->do_field(&fd);
1353 }
1354 }
1355 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1356 }
1357
1358
1359 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1360 if (array_klasses() != NULL)
1361 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1362 }
1363
1364 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1365 if (array_klasses() != NULL)
1366 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1367 }
1368
1369 #ifdef ASSERT
1370 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1371 int len = methods->length();
1372 for (int index = 0; index < len; index++) {
1373 Method* m = methods->at(index);
1374 assert(m->is_method(), "must be method");
1375 if (m->signature() == signature && m->name() == name) {
1376 return index;
1377 }
1378 }
1379 return -1;
1380 }
1381 #endif
1382
1383 static int binary_search(Array<Method*>* methods, Symbol* name) {
1384 int len = methods->length();
1385 // methods are sorted, so do binary search
1386 int l = 0;
1387 int h = len - 1;
1388 while (l <= h) {
1389 int mid = (l + h) >> 1;
1390 Method* m = methods->at(mid);
1391 assert(m->is_method(), "must be method");
1392 int res = m->name()->fast_compare(name);
1393 if (res == 0) {
1394 return mid;
1395 } else if (res < 0) {
1396 l = mid + 1;
1397 } else {
1398 h = mid - 1;
1399 }
1400 }
1401 return -1;
1402 }
1403
1404 // find_method looks up the name/signature in the local methods array
1405 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1406 return find_method_impl(name, signature, false);
1407 }
1408
1409 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const {
1410 return InstanceKlass::find_method_impl(methods(), name, signature, skipping_overpass);
1411 }
1412
1413 // find_instance_method looks up the name/signature in the local methods array
1414 // and skips over static methods
1415 Method* InstanceKlass::find_instance_method(
1416 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1417 Method* meth = InstanceKlass::find_method(methods, name, signature);
1418 if (meth != NULL && meth->is_static()) {
1419 meth = NULL;
1420 }
1421 return meth;
1422 }
1423
1424 // find_method looks up the name/signature in the local methods array
1425 Method* InstanceKlass::find_method(
1426 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1427 return InstanceKlass::find_method_impl(methods, name, signature, false);
1428 }
1429
1430 Method* InstanceKlass::find_method_impl(
1431 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1432 int hit = find_method_index(methods, name, signature, skipping_overpass);
1433 return hit >= 0 ? methods->at(hit): NULL;
1434 }
1435
1436 // Used directly for default_methods to find the index into the
1437 // default_vtable_indices, and indirectly by find_method
1438 // find_method_index looks in the local methods array to return the index
1439 // of the matching name/signature. If, overpass methods are being ignored,
1440 // the search continues to find a potential non-overpass match. This capability
1441 // is important during method resolution to prefer a static method, for example,
1442 // over an overpass method.
1443 int InstanceKlass::find_method_index(
1444 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1445 int hit = binary_search(methods, name);
1446 if (hit != -1) {
1447 Method* m = methods->at(hit);
1448 // Do linear search to find matching signature. First, quick check
1449 // for common case, ignoring overpasses if requested.
1450 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return hit;
1451
1452 // search downwards through overloaded methods
1453 int i;
1454 for (i = hit - 1; i >= 0; --i) {
1455 Method* m = methods->at(i);
1456 assert(m->is_method(), "must be method");
1457 if (m->name() != name) break;
1458 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1459 }
1460 // search upwards
1461 for (i = hit + 1; i < methods->length(); ++i) {
1462 Method* m = methods->at(i);
1463 assert(m->is_method(), "must be method");
1464 if (m->name() != name) break;
1465 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1466 }
1467 // not found
1468 #ifdef ASSERT
1469 int index = skipping_overpass ? -1 : linear_search(methods, name, signature);
1470 assert(index == -1, err_msg("binary search should have found entry %d", index));
1471 #endif
1472 }
1473 return -1;
1474 }
1475 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1476 return find_method_by_name(methods(), name, end);
1477 }
1478
1479 int InstanceKlass::find_method_by_name(
1480 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1481 assert(end_ptr != NULL, "just checking");
1482 int start = binary_search(methods, name);
1483 int end = start + 1;
1484 if (start != -1) {
1485 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1486 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1487 *end_ptr = end;
1488 return start;
1489 }
1490 return -1;
1491 }
1492
1493 // uncached_lookup_method searches both the local class methods array and all
1494 // superclasses methods arrays, skipping any overpass methods in superclasses.
1495 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const {
1496 MethodLookupMode lookup_mode = mode;
1497 Klass* klass = const_cast<InstanceKlass*>(this);
1498 while (klass != NULL) {
1499 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, (lookup_mode == skip_overpass));
1500 if (method != NULL) {
1501 return method;
1502 }
1503 klass = InstanceKlass::cast(klass)->super();
1504 lookup_mode = skip_overpass; // Always ignore overpass methods in superclasses
1505 }
1506 return NULL;
1507 }
1508
1509 #ifdef ASSERT
1510 // search through class hierarchy and return true if this class or
1511 // one of the superclasses was redefined
1512 bool InstanceKlass::has_redefined_this_or_super() const {
1513 const InstanceKlass* klass = this;
1514 while (klass != NULL) {
1515 if (klass->has_been_redefined()) {
1516 return true;
1517 }
1518 klass = InstanceKlass::cast(klass->super());
1519 }
1520 return false;
1521 }
1522 #endif
1523
1524 // lookup a method in the default methods list then in all transitive interfaces
1525 // Do NOT return private or static methods
1526 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1527 Symbol* signature) const {
1528 Method* m = NULL;
1529 if (default_methods() != NULL) {
1530 m = find_method(default_methods(), name, signature);
1531 }
1532 // Look up interfaces
1533 if (m == NULL) {
1534 m = lookup_method_in_all_interfaces(name, signature, normal);
1535 }
1536 return m;
1537 }
1538
1539 // lookup a method in all the interfaces that this class implements
1540 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1541 // They should only be found in the initial InterfaceMethodRef
1542 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1543 Symbol* signature,
1544 MethodLookupMode mode) const {
1545 Array<Klass*>* all_ifs = transitive_interfaces();
1546 int num_ifs = all_ifs->length();
1547 InstanceKlass *ik = NULL;
1548 for (int i = 0; i < num_ifs; i++) {
1549 ik = InstanceKlass::cast(all_ifs->at(i));
1550 Method* m = ik->lookup_method(name, signature);
1551 if (m != NULL && m->is_public() && !m->is_static() &&
1552 ((mode != skip_defaults) || !m->is_default_method())) {
1553 return m;
1554 }
1555 }
1556 return NULL;
1557 }
1558
1559 /* jni_id_for_impl for jfieldIds only */
1560 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1561 MutexLocker ml(JfieldIdCreation_lock);
1562 // Retry lookup after we got the lock
1563 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1564 if (probe == NULL) {
1565 // Slow case, allocate new static field identifier
1566 probe = new JNIid(this_k(), offset, this_k->jni_ids());
1567 this_k->set_jni_ids(probe);
1568 }
1569 return probe;
1570 }
1571
1572
1573 /* jni_id_for for jfieldIds only */
1574 JNIid* InstanceKlass::jni_id_for(int offset) {
1575 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1576 if (probe == NULL) {
1577 probe = jni_id_for_impl(this, offset);
1578 }
1579 return probe;
1580 }
1581
1582 u2 InstanceKlass::enclosing_method_data(int offset) {
1583 Array<jushort>* inner_class_list = inner_classes();
1584 if (inner_class_list == NULL) {
1585 return 0;
1586 }
1587 int length = inner_class_list->length();
1588 if (length % inner_class_next_offset == 0) {
1589 return 0;
1590 } else {
1591 int index = length - enclosing_method_attribute_size;
1592 assert(offset < enclosing_method_attribute_size, "invalid offset");
1593 return inner_class_list->at(index + offset);
1594 }
1595 }
1596
1597 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1598 u2 method_index) {
1599 Array<jushort>* inner_class_list = inner_classes();
1600 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1601 int length = inner_class_list->length();
1602 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1603 int index = length - enclosing_method_attribute_size;
1604 inner_class_list->at_put(
1605 index + enclosing_method_class_index_offset, class_index);
1606 inner_class_list->at_put(
1607 index + enclosing_method_method_index_offset, method_index);
1608 }
1609 }
1610
1611 // Lookup or create a jmethodID.
1612 // This code is called by the VMThread and JavaThreads so the
1613 // locking has to be done very carefully to avoid deadlocks
1614 // and/or other cache consistency problems.
1615 //
1616 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1617 size_t idnum = (size_t)method_h->method_idnum();
1618 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1619 size_t length = 0;
1620 jmethodID id = NULL;
1621
1622 // We use a double-check locking idiom here because this cache is
1623 // performance sensitive. In the normal system, this cache only
1624 // transitions from NULL to non-NULL which is safe because we use
1625 // release_set_methods_jmethod_ids() to advertise the new cache.
1626 // A partially constructed cache should never be seen by a racing
1627 // thread. We also use release_store_ptr() to save a new jmethodID
1628 // in the cache so a partially constructed jmethodID should never be
1629 // seen either. Cache reads of existing jmethodIDs proceed without a
1630 // lock, but cache writes of a new jmethodID requires uniqueness and
1631 // creation of the cache itself requires no leaks so a lock is
1632 // generally acquired in those two cases.
1633 //
1634 // If the RedefineClasses() API has been used, then this cache can
1635 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1636 // Cache creation requires no leaks and we require safety between all
1637 // cache accesses and freeing of the old cache so a lock is generally
1638 // acquired when the RedefineClasses() API has been used.
1639
1640 if (jmeths != NULL) {
1641 // the cache already exists
1642 if (!ik_h->idnum_can_increment()) {
1643 // the cache can't grow so we can just get the current values
1644 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1645 } else {
1646 // cache can grow so we have to be more careful
1647 if (Threads::number_of_threads() == 0 ||
1648 SafepointSynchronize::is_at_safepoint()) {
1649 // we're single threaded or at a safepoint - no locking needed
1650 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1651 } else {
1652 MutexLocker ml(JmethodIdCreation_lock);
1653 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1654 }
1655 }
1656 }
1657 // implied else:
1658 // we need to allocate a cache so default length and id values are good
1659
1660 if (jmeths == NULL || // no cache yet
1661 length <= idnum || // cache is too short
1662 id == NULL) { // cache doesn't contain entry
1663
1664 // This function can be called by the VMThread so we have to do all
1665 // things that might block on a safepoint before grabbing the lock.
1666 // Otherwise, we can deadlock with the VMThread or have a cache
1667 // consistency issue. These vars keep track of what we might have
1668 // to free after the lock is dropped.
1669 jmethodID to_dealloc_id = NULL;
1670 jmethodID* to_dealloc_jmeths = NULL;
1671
1672 // may not allocate new_jmeths or use it if we allocate it
1673 jmethodID* new_jmeths = NULL;
1674 if (length <= idnum) {
1675 // allocate a new cache that might be used
1676 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1677 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1678 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1679 // cache size is stored in element[0], other elements offset by one
1680 new_jmeths[0] = (jmethodID)size;
1681 }
1682
1683 // allocate a new jmethodID that might be used
1684 jmethodID new_id = NULL;
1685 if (method_h->is_old() && !method_h->is_obsolete()) {
1686 // The method passed in is old (but not obsolete), we need to use the current version
1687 Method* current_method = ik_h->method_with_idnum((int)idnum);
1688 assert(current_method != NULL, "old and but not obsolete, so should exist");
1689 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1690 } else {
1691 // It is the current version of the method or an obsolete method,
1692 // use the version passed in
1693 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1694 }
1695
1696 if (Threads::number_of_threads() == 0 ||
1697 SafepointSynchronize::is_at_safepoint()) {
1698 // we're single threaded or at a safepoint - no locking needed
1699 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1700 &to_dealloc_id, &to_dealloc_jmeths);
1701 } else {
1702 MutexLocker ml(JmethodIdCreation_lock);
1703 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1704 &to_dealloc_id, &to_dealloc_jmeths);
1705 }
1706
1707 // The lock has been dropped so we can free resources.
1708 // Free up either the old cache or the new cache if we allocated one.
1709 if (to_dealloc_jmeths != NULL) {
1710 FreeHeap(to_dealloc_jmeths);
1711 }
1712 // free up the new ID since it wasn't needed
1713 if (to_dealloc_id != NULL) {
1714 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1715 }
1716 }
1717 return id;
1718 }
1719
1720
1721 // Common code to fetch the jmethodID from the cache or update the
1722 // cache with the new jmethodID. This function should never do anything
1723 // that causes the caller to go to a safepoint or we can deadlock with
1724 // the VMThread or have cache consistency issues.
1725 //
1726 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1727 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1728 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1729 jmethodID** to_dealloc_jmeths_p) {
1730 assert(new_id != NULL, "sanity check");
1731 assert(to_dealloc_id_p != NULL, "sanity check");
1732 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1733 assert(Threads::number_of_threads() == 0 ||
1734 SafepointSynchronize::is_at_safepoint() ||
1735 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1736
1737 // reacquire the cache - we are locked, single threaded or at a safepoint
1738 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1739 jmethodID id = NULL;
1740 size_t length = 0;
1741
1742 if (jmeths == NULL || // no cache yet
1743 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1744 if (jmeths != NULL) {
1745 // copy any existing entries from the old cache
1746 for (size_t index = 0; index < length; index++) {
1747 new_jmeths[index+1] = jmeths[index+1];
1748 }
1749 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1750 }
1751 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1752 } else {
1753 // fetch jmethodID (if any) from the existing cache
1754 id = jmeths[idnum+1];
1755 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1756 }
1757 if (id == NULL) {
1758 // No matching jmethodID in the existing cache or we have a new
1759 // cache or we just grew the cache. This cache write is done here
1760 // by the first thread to win the foot race because a jmethodID
1761 // needs to be unique once it is generally available.
1762 id = new_id;
1763
1764 // The jmethodID cache can be read while unlocked so we have to
1765 // make sure the new jmethodID is complete before installing it
1766 // in the cache.
1767 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1768 } else {
1769 *to_dealloc_id_p = new_id; // save new id for later delete
1770 }
1771 return id;
1772 }
1773
1774
1775 // Common code to get the jmethodID cache length and the jmethodID
1776 // value at index idnum if there is one.
1777 //
1778 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1779 size_t idnum, size_t *length_p, jmethodID* id_p) {
1780 assert(cache != NULL, "sanity check");
1781 assert(length_p != NULL, "sanity check");
1782 assert(id_p != NULL, "sanity check");
1783
1784 // cache size is stored in element[0], other elements offset by one
1785 *length_p = (size_t)cache[0];
1786 if (*length_p <= idnum) { // cache is too short
1787 *id_p = NULL;
1788 } else {
1789 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1790 }
1791 }
1792
1793
1794 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1795 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1796 size_t idnum = (size_t)method->method_idnum();
1797 jmethodID* jmeths = methods_jmethod_ids_acquire();
1798 size_t length; // length assigned as debugging crumb
1799 jmethodID id = NULL;
1800 if (jmeths != NULL && // If there is a cache
1801 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1802 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1803 }
1804 return id;
1805 }
1806
1807 int nmethodBucket::decrement() {
1808 return Atomic::add(-1, (volatile int *)&_count);
1809 }
1810
1811 //
1812 // Walk the list of dependent nmethods searching for nmethods which
1813 // are dependent on the changes that were passed in and mark them for
1814 // deoptimization. Returns the number of nmethods found.
1815 //
1816 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1817 assert_locked_or_safepoint(CodeCache_lock);
1818 int found = 0;
1819 nmethodBucket* b = _dependencies;
1820 while (b != NULL) {
1821 nmethod* nm = b->get_nmethod();
1822 // since dependencies aren't removed until an nmethod becomes a zombie,
1823 // the dependency list may contain nmethods which aren't alive.
1824 if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1825 if (TraceDependencies) {
1826 ResourceMark rm;
1827 tty->print_cr("Marked for deoptimization");
1828 tty->print_cr(" context = %s", this->external_name());
1829 changes.print();
1830 nm->print();
1831 nm->print_dependencies();
1832 }
1833 nm->mark_for_deoptimization();
1834 found++;
1835 }
1836 b = b->next();
1837 }
1838 return found;
1839 }
1840
1841 void InstanceKlass::clean_dependent_nmethods() {
1842 assert_locked_or_safepoint(CodeCache_lock);
1843
1844 if (has_unloaded_dependent()) {
1845 nmethodBucket* b = _dependencies;
1846 nmethodBucket* last = NULL;
1847 while (b != NULL) {
1848 assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
1849
1850 nmethodBucket* next = b->next();
1851
1852 if (b->count() == 0) {
1853 if (last == NULL) {
1854 _dependencies = next;
1855 } else {
1856 last->set_next(next);
1857 }
1858 delete b;
1859 // last stays the same.
1860 } else {
1861 last = b;
1862 }
1863
1864 b = next;
1865 }
1866 set_has_unloaded_dependent(false);
1867 }
1868 #ifdef ASSERT
1869 else {
1870 // Verification
1871 for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) {
1872 assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
1873 assert(b->count() != 0, "empty buckets need to be cleaned");
1874 }
1875 }
1876 #endif
1877 }
1878
1879 //
1880 // Add an nmethodBucket to the list of dependencies for this nmethod.
1881 // It's possible that an nmethod has multiple dependencies on this klass
1882 // so a count is kept for each bucket to guarantee that creation and
1883 // deletion of dependencies is consistent.
1884 //
1885 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1886 assert_locked_or_safepoint(CodeCache_lock);
1887 nmethodBucket* b = _dependencies;
1888 nmethodBucket* last = NULL;
1889 while (b != NULL) {
1890 if (nm == b->get_nmethod()) {
1891 b->increment();
1892 return;
1893 }
1894 b = b->next();
1895 }
1896 _dependencies = new nmethodBucket(nm, _dependencies);
1897 }
1898
1899
1900 //
1901 // Decrement count of the nmethod in the dependency list and remove
1902 // the bucket competely when the count goes to 0. This method must
1903 // find a corresponding bucket otherwise there's a bug in the
1904 // recording of dependecies.
1905 //
1906 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1907 assert_locked_or_safepoint(CodeCache_lock);
1908 nmethodBucket* b = _dependencies;
1909 nmethodBucket* last = NULL;
1910 while (b != NULL) {
1911 if (nm == b->get_nmethod()) {
1912 int val = b->decrement();
1913 guarantee(val >= 0, err_msg("Underflow: %d", val));
1914 if (val == 0) {
1915 set_has_unloaded_dependent(true);
1916 }
1917 return;
1918 }
1919 last = b;
1920 b = b->next();
1921 }
1922 #ifdef ASSERT
1923 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1924 nm->print();
1925 #endif // ASSERT
1926 ShouldNotReachHere();
1927 }
1928
1929
1930 #ifndef PRODUCT
1931 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1932 nmethodBucket* b = _dependencies;
1933 int idx = 0;
1934 while (b != NULL) {
1935 nmethod* nm = b->get_nmethod();
1936 tty->print("[%d] count=%d { ", idx++, b->count());
1937 if (!verbose) {
1938 nm->print_on(tty, "nmethod");
1939 tty->print_cr(" } ");
1940 } else {
1941 nm->print();
1942 nm->print_dependencies();
1943 tty->print_cr("--- } ");
1944 }
1945 b = b->next();
1946 }
1947 }
1948
1949
1950 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1951 nmethodBucket* b = _dependencies;
1952 while (b != NULL) {
1953 if (nm == b->get_nmethod()) {
1954 #ifdef ASSERT
1955 int count = b->count();
1956 assert(count >= 0, err_msg("count shouldn't be negative: %d", count));
1957 #endif
1958 return true;
1959 }
1960 b = b->next();
1961 }
1962 return false;
1963 }
1964 #endif //PRODUCT
1965
1966
1967 // Garbage collection
1968
1969 void InstanceKlass::oop_follow_contents(oop obj) {
1970 assert(obj != NULL, "can't follow the content of NULL object");
1971 MarkSweep::follow_klass(obj->klass());
1972 InstanceKlass_OOP_MAP_ITERATE( \
1973 obj, \
1974 MarkSweep::mark_and_push(p), \
1975 assert_is_in_closed_subset)
1976 }
1977
1978 #if INCLUDE_ALL_GCS
1979 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
1980 oop obj) {
1981 assert(obj != NULL, "can't follow the content of NULL object");
1982 PSParallelCompact::follow_klass(cm, obj->klass());
1983 // Only mark the header and let the scan of the meta-data mark
1984 // everything else.
1985 InstanceKlass_OOP_MAP_ITERATE( \
1986 obj, \
1987 PSParallelCompact::mark_and_push(cm, p), \
1988 assert_is_in)
1989 }
1990 #endif // INCLUDE_ALL_GCS
1991
1992 int InstanceKlass::oop_adjust_pointers(oop obj) {
1993 int size = size_helper();
1994 InstanceKlass_OOP_MAP_ITERATE( \
1995 obj, \
1996 MarkSweep::adjust_pointer(p), \
1997 assert_is_in)
1998 return size;
1999 }
2000
2001 #if INCLUDE_ALL_GCS
2002 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2003 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2004 obj, \
2005 if (PSScavenge::should_scavenge(p)) { \
2006 pm->claim_or_forward_depth(p); \
2007 }, \
2008 assert_nothing )
2009 }
2010
2011 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2012 int size = size_helper();
2013 InstanceKlass_OOP_MAP_ITERATE( \
2014 obj, \
2015 PSParallelCompact::adjust_pointer(p), \
2016 assert_is_in)
2017 return size;
2018 }
2019
2020 #endif // INCLUDE_ALL_GCS
2021
2022 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2023 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2024 if (is_interface()) {
2025 if (ClassUnloading) {
2026 Klass* impl = implementor();
2027 if (impl != NULL) {
2028 if (!impl->is_loader_alive(is_alive)) {
2029 // remove this guy
2030 Klass** klass = adr_implementor();
2031 assert(klass != NULL, "null klass");
2032 if (klass != NULL) {
2033 *klass = NULL;
2034 }
2035 }
2036 }
2037 }
2038 }
2039 }
2040
2041 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2042 for (int m = 0; m < methods()->length(); m++) {
2043 MethodData* mdo = methods()->at(m)->method_data();
2044 if (mdo != NULL) {
2045 mdo->clean_method_data(is_alive);
2046 }
2047 }
2048 }
2049
2050
2051 static void remove_unshareable_in_class(Klass* k) {
2052 // remove klass's unshareable info
2053 k->remove_unshareable_info();
2054 }
2055
2056 void InstanceKlass::remove_unshareable_info() {
2057 Klass::remove_unshareable_info();
2058 // Unlink the class
2059 if (is_linked()) {
2060 unlink_class();
2061 }
2062 init_implementor();
2063
2064 constants()->remove_unshareable_info();
2065
2066 for (int i = 0; i < methods()->length(); i++) {
2067 Method* m = methods()->at(i);
2068 m->remove_unshareable_info();
2069 }
2070
2071 // do array classes also.
2072 array_klasses_do(remove_unshareable_in_class);
2073 }
2074
2075 void restore_unshareable_in_class(Klass* k, TRAPS) {
2076 k->restore_unshareable_info(CHECK);
2077 }
2078
2079 void InstanceKlass::restore_unshareable_info(TRAPS) {
2080 Klass::restore_unshareable_info(CHECK);
2081 instanceKlassHandle ik(THREAD, this);
2082
2083 Array<Method*>* methods = ik->methods();
2084 int num_methods = methods->length();
2085 for (int index2 = 0; index2 < num_methods; ++index2) {
2086 methodHandle m(THREAD, methods->at(index2));
2087 m->restore_unshareable_info(CHECK);
2088 }
2089 if (JvmtiExport::has_redefined_a_class()) {
2090 // Reinitialize vtable because RedefineClasses may have changed some
2091 // entries in this vtable for super classes so the CDS vtable might
2092 // point to old or obsolete entries. RedefineClasses doesn't fix up
2093 // vtables in the shared system dictionary, only the main one.
2094 // It also redefines the itable too so fix that too.
2095 ResourceMark rm(THREAD);
2096 ik->vtable()->initialize_vtable(false, CHECK);
2097 ik->itable()->initialize_itable(false, CHECK);
2098 }
2099
2100 // restore constant pool resolved references
2101 ik->constants()->restore_unshareable_info(CHECK);
2102
2103 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2104 }
2105
2106 static void clear_all_breakpoints(Method* m) {
2107 m->clear_all_breakpoints();
2108 }
2109
2110
2111 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2112 // notify the debugger
2113 if (JvmtiExport::should_post_class_unload()) {
2114 JvmtiExport::post_class_unload(ik);
2115 }
2116
2117 // notify ClassLoadingService of class unload
2118 ClassLoadingService::notify_class_unloaded(ik);
2119 }
2120
2121 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2122 // Clean up C heap
2123 ik->release_C_heap_structures();
2124 ik->constants()->release_C_heap_structures();
2125 }
2126
2127 void InstanceKlass::release_C_heap_structures() {
2128
2129 // Can't release the constant pool here because the constant pool can be
2130 // deallocated separately from the InstanceKlass for default methods and
2131 // redefine classes.
2132
2133 // Deallocate oop map cache
2134 if (_oop_map_cache != NULL) {
2135 delete _oop_map_cache;
2136 _oop_map_cache = NULL;
2137 }
2138
2139 // Deallocate JNI identifiers for jfieldIDs
2140 JNIid::deallocate(jni_ids());
2141 set_jni_ids(NULL);
2142
2143 jmethodID* jmeths = methods_jmethod_ids_acquire();
2144 if (jmeths != (jmethodID*)NULL) {
2145 release_set_methods_jmethod_ids(NULL);
2146 FreeHeap(jmeths);
2147 }
2148
2149 // Deallocate MemberNameTable
2150 {
2151 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2152 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2153 MemberNameTable* mnt = member_names();
2154 if (mnt != NULL) {
2155 delete mnt;
2156 set_member_names(NULL);
2157 }
2158 }
2159
2160 // release dependencies
2161 nmethodBucket* b = _dependencies;
2162 _dependencies = NULL;
2163 while (b != NULL) {
2164 nmethodBucket* next = b->next();
2165 delete b;
2166 b = next;
2167 }
2168
2169 // Deallocate breakpoint records
2170 if (breakpoints() != 0x0) {
2171 methods_do(clear_all_breakpoints);
2172 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2173 }
2174
2175 // deallocate information about previous versions
2176 if (_previous_versions != NULL) {
2177 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2178 PreviousVersionNode * pv_node = _previous_versions->at(i);
2179 delete pv_node;
2180 }
2181 delete _previous_versions;
2182 _previous_versions = NULL;
2183 }
2184
2185 // deallocate the cached class file
2186 if (_cached_class_file != NULL) {
2187 os::free(_cached_class_file, mtClass);
2188 _cached_class_file = NULL;
2189 }
2190
2191 // Decrement symbol reference counts associated with the unloaded class.
2192 if (_name != NULL) _name->decrement_refcount();
2193 // unreference array name derived from this class name (arrays of an unloaded
2194 // class can't be referenced anymore).
2195 if (_array_name != NULL) _array_name->decrement_refcount();
2196 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2197
2198 assert(_total_instanceKlass_count >= 1, "Sanity check");
2199 Atomic::dec(&_total_instanceKlass_count);
2200 }
2201
2202 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2203 if (array == NULL) {
2204 _source_debug_extension = NULL;
2205 } else {
2206 // Adding one to the attribute length in order to store a null terminator
2207 // character could cause an overflow because the attribute length is
2208 // already coded with an u4 in the classfile, but in practice, it's
2209 // unlikely to happen.
2210 assert((length+1) > length, "Overflow checking");
2211 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2212 for (int i = 0; i < length; i++) {
2213 sde[i] = array[i];
2214 }
2215 sde[length] = '\0';
2216 _source_debug_extension = sde;
2217 }
2218 }
2219
2220 address InstanceKlass::static_field_addr(int offset) {
2221 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2222 }
2223
2224
2225 const char* InstanceKlass::signature_name() const {
2226 int hash_len = 0;
2227 char hash_buf[40];
2228
2229 // If this is an anonymous class, append a hash to make the name unique
2230 if (is_anonymous()) {
2231 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2232 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
2233 hash_len = (int)strlen(hash_buf);
2234 }
2235
2236 // Get the internal name as a c string
2237 const char* src = (const char*) (name()->as_C_string());
2238 const int src_length = (int)strlen(src);
2239
2240 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2241
2242 // Add L as type indicator
2243 int dest_index = 0;
2244 dest[dest_index++] = 'L';
2245
2246 // Add the actual class name
2247 for (int src_index = 0; src_index < src_length; ) {
2248 dest[dest_index++] = src[src_index++];
2249 }
2250
2251 // If we have a hash, append it
2252 for (int hash_index = 0; hash_index < hash_len; ) {
2253 dest[dest_index++] = hash_buf[hash_index++];
2254 }
2255
2256 // Add the semicolon and the NULL
2257 dest[dest_index++] = ';';
2258 dest[dest_index] = '\0';
2259 return dest;
2260 }
2261
2262 // different verisons of is_same_class_package
2263 bool InstanceKlass::is_same_class_package(Klass* class2) {
2264 Klass* class1 = this;
2265 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2266 Symbol* classname1 = class1->name();
2267
2268 if (class2->oop_is_objArray()) {
2269 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2270 }
2271 oop classloader2;
2272 if (class2->oop_is_instance()) {
2273 classloader2 = InstanceKlass::cast(class2)->class_loader();
2274 } else {
2275 assert(class2->oop_is_typeArray(), "should be type array");
2276 classloader2 = NULL;
2277 }
2278 Symbol* classname2 = class2->name();
2279
2280 return InstanceKlass::is_same_class_package(classloader1, classname1,
2281 classloader2, classname2);
2282 }
2283
2284 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2285 Klass* class1 = this;
2286 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2287 Symbol* classname1 = class1->name();
2288
2289 return InstanceKlass::is_same_class_package(classloader1, classname1,
2290 classloader2, classname2);
2291 }
2292
2293 // return true if two classes are in the same package, classloader
2294 // and classname information is enough to determine a class's package
2295 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2296 oop class_loader2, Symbol* class_name2) {
2297 if (class_loader1 != class_loader2) {
2298 return false;
2299 } else if (class_name1 == class_name2) {
2300 return true; // skip painful bytewise comparison
2301 } else {
2302 ResourceMark rm;
2303
2304 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2305 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2306 // Otherwise, we just compare jbyte values between the strings.
2307 const jbyte *name1 = class_name1->base();
2308 const jbyte *name2 = class_name2->base();
2309
2310 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2311 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2312
2313 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2314 // One of the two doesn't have a package. Only return true
2315 // if the other one also doesn't have a package.
2316 return last_slash1 == last_slash2;
2317 } else {
2318 // Skip over '['s
2319 if (*name1 == '[') {
2320 do {
2321 name1++;
2322 } while (*name1 == '[');
2323 if (*name1 != 'L') {
2324 // Something is terribly wrong. Shouldn't be here.
2325 return false;
2326 }
2327 }
2328 if (*name2 == '[') {
2329 do {
2330 name2++;
2331 } while (*name2 == '[');
2332 if (*name2 != 'L') {
2333 // Something is terribly wrong. Shouldn't be here.
2334 return false;
2335 }
2336 }
2337
2338 // Check that package part is identical
2339 int length1 = last_slash1 - name1;
2340 int length2 = last_slash2 - name2;
2341
2342 return UTF8::equal(name1, length1, name2, length2);
2343 }
2344 }
2345 }
2346
2347 // Returns true iff super_method can be overridden by a method in targetclassname
2348 // See JSL 3rd edition 8.4.6.1
2349 // Assumes name-signature match
2350 // "this" is InstanceKlass of super_method which must exist
2351 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2352 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2353 // Private methods can not be overridden
2354 if (super_method->is_private()) {
2355 return false;
2356 }
2357 // If super method is accessible, then override
2358 if ((super_method->is_protected()) ||
2359 (super_method->is_public())) {
2360 return true;
2361 }
2362 // Package-private methods are not inherited outside of package
2363 assert(super_method->is_package_private(), "must be package private");
2364 return(is_same_class_package(targetclassloader(), targetclassname));
2365 }
2366
2367 /* defined for now in jvm.cpp, for historical reasons *--
2368 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2369 Symbol*& simple_name_result, TRAPS) {
2370 ...
2371 }
2372 */
2373
2374 // tell if two classes have the same enclosing class (at package level)
2375 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2376 Klass* class2_oop, TRAPS) {
2377 if (class2_oop == class1()) return true;
2378 if (!class2_oop->oop_is_instance()) return false;
2379 instanceKlassHandle class2(THREAD, class2_oop);
2380
2381 // must be in same package before we try anything else
2382 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2383 return false;
2384
2385 // As long as there is an outer1.getEnclosingClass,
2386 // shift the search outward.
2387 instanceKlassHandle outer1 = class1;
2388 for (;;) {
2389 // As we walk along, look for equalities between outer1 and class2.
2390 // Eventually, the walks will terminate as outer1 stops
2391 // at the top-level class around the original class.
2392 bool ignore_inner_is_member;
2393 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2394 CHECK_false);
2395 if (next == NULL) break;
2396 if (next == class2()) return true;
2397 outer1 = instanceKlassHandle(THREAD, next);
2398 }
2399
2400 // Now do the same for class2.
2401 instanceKlassHandle outer2 = class2;
2402 for (;;) {
2403 bool ignore_inner_is_member;
2404 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2405 CHECK_false);
2406 if (next == NULL) break;
2407 // Might as well check the new outer against all available values.
2408 if (next == class1()) return true;
2409 if (next == outer1()) return true;
2410 outer2 = instanceKlassHandle(THREAD, next);
2411 }
2412
2413 // If by this point we have not found an equality between the
2414 // two classes, we know they are in separate package members.
2415 return false;
2416 }
2417
2418
2419 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2420 jint access = access_flags().as_int();
2421
2422 // But check if it happens to be member class.
2423 instanceKlassHandle ik(THREAD, this);
2424 InnerClassesIterator iter(ik);
2425 for (; !iter.done(); iter.next()) {
2426 int ioff = iter.inner_class_info_index();
2427 // Inner class attribute can be zero, skip it.
2428 // Strange but true: JVM spec. allows null inner class refs.
2429 if (ioff == 0) continue;
2430
2431 // only look at classes that are already loaded
2432 // since we are looking for the flags for our self.
2433 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2434 if ((ik->name() == inner_name)) {
2435 // This is really a member class.
2436 access = iter.inner_access_flags();
2437 break;
2438 }
2439 }
2440 // Remember to strip ACC_SUPER bit
2441 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2442 }
2443
2444 jint InstanceKlass::jvmti_class_status() const {
2445 jint result = 0;
2446
2447 if (is_linked()) {
2448 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2449 }
2450
2451 if (is_initialized()) {
2452 assert(is_linked(), "Class status is not consistent");
2453 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2454 }
2455 if (is_in_error_state()) {
2456 result |= JVMTI_CLASS_STATUS_ERROR;
2457 }
2458 return result;
2459 }
2460
2461 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2462 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2463 int method_table_offset_in_words = ioe->offset()/wordSize;
2464 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2465 / itableOffsetEntry::size();
2466
2467 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2468 // If the interface isn't implemented by the receiver class,
2469 // the VM should throw IncompatibleClassChangeError.
2470 if (cnt >= nof_interfaces) {
2471 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2472 }
2473
2474 Klass* ik = ioe->interface_klass();
2475 if (ik == holder) break;
2476 }
2477
2478 itableMethodEntry* ime = ioe->first_method_entry(this);
2479 Method* m = ime[index].method();
2480 if (m == NULL) {
2481 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2482 }
2483 return m;
2484 }
2485
2486
2487 #if INCLUDE_JVMTI
2488 // update default_methods for redefineclasses for methods that are
2489 // not yet in the vtable due to concurrent subclass define and superinterface
2490 // redefinition
2491 // Note: those in the vtable, should have been updated via adjust_method_entries
2492 void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods,
2493 int methods_length, bool* trace_name_printed) {
2494 // search the default_methods for uses of either obsolete or EMCP methods
2495 if (default_methods() != NULL) {
2496 for (int j = 0; j < methods_length; j++) {
2497 Method* old_method = old_methods[j];
2498 Method* new_method = new_methods[j];
2499
2500 for (int index = 0; index < default_methods()->length(); index ++) {
2501 if (default_methods()->at(index) == old_method) {
2502 default_methods()->at_put(index, new_method);
2503 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2504 if (!(*trace_name_printed)) {
2505 // RC_TRACE_MESG macro has an embedded ResourceMark
2506 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2507 external_name(),
2508 old_method->method_holder()->external_name()));
2509 *trace_name_printed = true;
2510 }
2511 RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2512 new_method->name()->as_C_string(),
2513 new_method->signature()->as_C_string()));
2514 }
2515 }
2516 }
2517 }
2518 }
2519 }
2520 #endif // INCLUDE_JVMTI
2521
2522 // On-stack replacement stuff
2523 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2524 // only one compilation can be active
2525 NEEDS_CLEANUP
2526 // This is a short non-blocking critical region, so the no safepoint check is ok.
2527 OsrList_lock->lock_without_safepoint_check();
2528 assert(n->is_osr_method(), "wrong kind of nmethod");
2529 n->set_osr_link(osr_nmethods_head());
2530 set_osr_nmethods_head(n);
2531 // Raise the highest osr level if necessary
2532 if (TieredCompilation) {
2533 Method* m = n->method();
2534 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2535 }
2536 // Remember to unlock again
2537 OsrList_lock->unlock();
2538
2539 // Get rid of the osr methods for the same bci that have lower levels.
2540 if (TieredCompilation) {
2541 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2542 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2543 if (inv != NULL && inv->is_in_use()) {
2544 inv->make_not_entrant();
2545 }
2546 }
2547 }
2548 }
2549
2550
2551 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2552 // This is a short non-blocking critical region, so the no safepoint check is ok.
2553 OsrList_lock->lock_without_safepoint_check();
2554 assert(n->is_osr_method(), "wrong kind of nmethod");
2555 nmethod* last = NULL;
2556 nmethod* cur = osr_nmethods_head();
2557 int max_level = CompLevel_none; // Find the max comp level excluding n
2558 Method* m = n->method();
2559 // Search for match
2560 while(cur != NULL && cur != n) {
2561 if (TieredCompilation && m == cur->method()) {
2562 // Find max level before n
2563 max_level = MAX2(max_level, cur->comp_level());
2564 }
2565 last = cur;
2566 cur = cur->osr_link();
2567 }
2568 nmethod* next = NULL;
2569 if (cur == n) {
2570 next = cur->osr_link();
2571 if (last == NULL) {
2572 // Remove first element
2573 set_osr_nmethods_head(next);
2574 } else {
2575 last->set_osr_link(next);
2576 }
2577 }
2578 n->set_osr_link(NULL);
2579 if (TieredCompilation) {
2580 cur = next;
2581 while (cur != NULL) {
2582 // Find max level after n
2583 if (m == cur->method()) {
2584 max_level = MAX2(max_level, cur->comp_level());
2585 }
2586 cur = cur->osr_link();
2587 }
2588 m->set_highest_osr_comp_level(max_level);
2589 }
2590 // Remember to unlock again
2591 OsrList_lock->unlock();
2592 }
2593
2594 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2595 // This is a short non-blocking critical region, so the no safepoint check is ok.
2596 OsrList_lock->lock_without_safepoint_check();
2597 nmethod* osr = osr_nmethods_head();
2598 nmethod* best = NULL;
2599 while (osr != NULL) {
2600 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2601 // There can be a time when a c1 osr method exists but we are waiting
2602 // for a c2 version. When c2 completes its osr nmethod we will trash
2603 // the c1 version and only be able to find the c2 version. However
2604 // while we overflow in the c1 code at back branches we don't want to
2605 // try and switch to the same code as we are already running
2606
2607 if (osr->method() == m &&
2608 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2609 if (match_level) {
2610 if (osr->comp_level() == comp_level) {
2611 // Found a match - return it.
2612 OsrList_lock->unlock();
2613 return osr;
2614 }
2615 } else {
2616 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2617 if (osr->comp_level() == CompLevel_highest_tier) {
2618 // Found the best possible - return it.
2619 OsrList_lock->unlock();
2620 return osr;
2621 }
2622 best = osr;
2623 }
2624 }
2625 }
2626 osr = osr->osr_link();
2627 }
2628 OsrList_lock->unlock();
2629 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2630 return best;
2631 }
2632 return NULL;
2633 }
2634
2635 void InstanceKlass::add_member_name(int index, Handle mem_name) {
2636 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2637 MutexLocker ml(MemberNameTable_lock);
2638 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2639 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2640
2641 if (_member_names == NULL) {
2642 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2643 }
2644 _member_names->add_member_name(index, mem_name_wref);
2645 }
2646
2647 oop InstanceKlass::get_member_name(int index) {
2648 MutexLocker ml(MemberNameTable_lock);
2649 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2650 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2651
2652 if (_member_names == NULL) {
2653 return NULL;
2654 }
2655 oop mem_name =_member_names->get_member_name(index);
2656 return mem_name;
2657 }
2658
2659 // -----------------------------------------------------------------------------------------------------
2660 // Printing
2661
2662 #ifndef PRODUCT
2663
2664 #define BULLET " - "
2665
2666 static const char* state_names[] = {
2667 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2668 };
2669
2670 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2671 for (int i = 0; i < len; i++) {
2672 intptr_t e = start[i];
2673 st->print("%d : " INTPTR_FORMAT, i, e);
2674 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2675 st->print(" ");
2676 ((Metadata*)e)->print_value_on(st);
2677 }
2678 st->cr();
2679 }
2680 }
2681
2682 void InstanceKlass::print_on(outputStream* st) const {
2683 assert(is_klass(), "must be klass");
2684 Klass::print_on(st);
2685
2686 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2687 st->print(BULLET"klass size: %d", size()); st->cr();
2688 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2689 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2690 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2691 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2692 st->print(BULLET"sub: ");
2693 Klass* sub = subklass();
2694 int n;
2695 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2696 if (n < MaxSubklassPrintSize) {
2697 sub->print_value_on(st);
2698 st->print(" ");
2699 }
2700 }
2701 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2702 st->cr();
2703
2704 if (is_interface()) {
2705 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2706 if (nof_implementors() == 1) {
2707 st->print_cr(BULLET"implementor: ");
2708 st->print(" ");
2709 implementor()->print_value_on(st);
2710 st->cr();
2711 }
2712 }
2713
2714 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2715 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2716 if (Verbose || WizardMode) {
2717 Array<Method*>* method_array = methods();
2718 for (int i = 0; i < method_array->length(); i++) {
2719 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2720 }
2721 }
2722 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2723 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2724 if (Verbose && default_methods() != NULL) {
2725 Array<Method*>* method_array = default_methods();
2726 for (int i = 0; i < method_array->length(); i++) {
2727 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2728 }
2729 }
2730 if (default_vtable_indices() != NULL) {
2731 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2732 }
2733 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2734 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2735 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2736 if (class_loader_data() != NULL) {
2737 st->print(BULLET"class loader data: ");
2738 class_loader_data()->print_value_on(st);
2739 st->cr();
2740 }
2741 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2742 if (source_file_name() != NULL) {
2743 st->print(BULLET"source file: ");
2744 source_file_name()->print_value_on(st);
2745 st->cr();
2746 }
2747 if (source_debug_extension() != NULL) {
2748 st->print(BULLET"source debug extension: ");
2749 st->print("%s", source_debug_extension());
2750 st->cr();
2751 }
2752 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2753 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2754 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2755 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2756 {
2757 bool have_pv = false;
2758 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
2759 for (PreviousVersionNode * pv_node = pvw.next_previous_version();
2760 pv_node != NULL; pv_node = pvw.next_previous_version()) {
2761 if (!have_pv)
2762 st->print(BULLET"previous version: ");
2763 have_pv = true;
2764 pv_node->prev_constant_pool()->print_value_on(st);
2765 }
2766 if (have_pv) st->cr();
2767 } // pvw is cleaned up
2768
2769 if (generic_signature() != NULL) {
2770 st->print(BULLET"generic signature: ");
2771 generic_signature()->print_value_on(st);
2772 st->cr();
2773 }
2774 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2775 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2776 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
2777 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2778 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
2779 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2780 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2781 FieldPrinter print_static_field(st);
2782 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2783 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2784 FieldPrinter print_nonstatic_field(st);
2785 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
2786
2787 st->print(BULLET"non-static oop maps: ");
2788 OopMapBlock* map = start_of_nonstatic_oop_maps();
2789 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2790 while (map < end_map) {
2791 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2792 map++;
2793 }
2794 st->cr();
2795 }
2796
2797 #endif //PRODUCT
2798
2799 void InstanceKlass::print_value_on(outputStream* st) const {
2800 assert(is_klass(), "must be klass");
2801 if (Verbose || WizardMode) access_flags().print_on(st);
2802 name()->print_value_on(st);
2803 }
2804
2805 #ifndef PRODUCT
2806
2807 void FieldPrinter::do_field(fieldDescriptor* fd) {
2808 _st->print(BULLET);
2809 if (_obj == NULL) {
2810 fd->print_on(_st);
2811 _st->cr();
2812 } else {
2813 fd->print_on_for(_st, _obj);
2814 _st->cr();
2815 }
2816 }
2817
2818
2819 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2820 Klass::oop_print_on(obj, st);
2821
2822 if (this == SystemDictionary::String_klass()) {
2823 typeArrayOop value = java_lang_String::value(obj);
2824 juint offset = java_lang_String::offset(obj);
2825 juint length = java_lang_String::length(obj);
2826 if (value != NULL &&
2827 value->is_typeArray() &&
2828 offset <= (juint) value->length() &&
2829 offset + length <= (juint) value->length()) {
2830 st->print(BULLET"string: ");
2831 java_lang_String::print(obj, st);
2832 st->cr();
2833 if (!WizardMode) return; // that is enough
2834 }
2835 }
2836
2837 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2838 FieldPrinter print_field(st, obj);
2839 do_nonstatic_fields(&print_field);
2840
2841 if (this == SystemDictionary::Class_klass()) {
2842 st->print(BULLET"signature: ");
2843 java_lang_Class::print_signature(obj, st);
2844 st->cr();
2845 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2846 st->print(BULLET"fake entry for mirror: ");
2847 mirrored_klass->print_value_on_maybe_null(st);
2848 st->cr();
2849 Klass* array_klass = java_lang_Class::array_klass(obj);
2850 st->print(BULLET"fake entry for array: ");
2851 array_klass->print_value_on_maybe_null(st);
2852 st->cr();
2853 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2854 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2855 Klass* real_klass = java_lang_Class::as_Klass(obj);
2856 if (real_klass != NULL && real_klass->oop_is_instance()) {
2857 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2858 }
2859 } else if (this == SystemDictionary::MethodType_klass()) {
2860 st->print(BULLET"signature: ");
2861 java_lang_invoke_MethodType::print_signature(obj, st);
2862 st->cr();
2863 }
2864 }
2865
2866 #endif //PRODUCT
2867
2868 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2869 st->print("a ");
2870 name()->print_value_on(st);
2871 obj->print_address_on(st);
2872 if (this == SystemDictionary::String_klass()
2873 && java_lang_String::value(obj) != NULL) {
2874 ResourceMark rm;
2875 int len = java_lang_String::length(obj);
2876 int plen = (len < 24 ? len : 12);
2877 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2878 st->print(" = \"%s\"", str);
2879 if (len > plen)
2880 st->print("...[%d]", len);
2881 } else if (this == SystemDictionary::Class_klass()) {
2882 Klass* k = java_lang_Class::as_Klass(obj);
2883 st->print(" = ");
2884 if (k != NULL) {
2885 k->print_value_on(st);
2886 } else {
2887 const char* tname = type2name(java_lang_Class::primitive_type(obj));
2888 st->print("%s", tname ? tname : "type?");
2889 }
2890 } else if (this == SystemDictionary::MethodType_klass()) {
2891 st->print(" = ");
2892 java_lang_invoke_MethodType::print_signature(obj, st);
2893 } else if (java_lang_boxing_object::is_instance(obj)) {
2894 st->print(" = ");
2895 java_lang_boxing_object::print(obj, st);
2896 } else if (this == SystemDictionary::LambdaForm_klass()) {
2897 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
2898 if (vmentry != NULL) {
2899 st->print(" => ");
2900 vmentry->print_value_on(st);
2901 }
2902 } else if (this == SystemDictionary::MemberName_klass()) {
2903 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
2904 if (vmtarget != NULL) {
2905 st->print(" = ");
2906 vmtarget->print_value_on(st);
2907 } else {
2908 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
2909 st->print(".");
2910 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
2911 }
2912 }
2913 }
2914
2915 const char* InstanceKlass::internal_name() const {
2916 return external_name();
2917 }
2918
2919 #if INCLUDE_SERVICES
2920 // Size Statistics
2921 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
2922 Klass::collect_statistics(sz);
2923
2924 sz->_inst_size = HeapWordSize * size_helper();
2925 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
2926 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
2927 sz->_nonstatic_oopmap_bytes = HeapWordSize *
2928 ((is_interface() || is_anonymous()) ?
2929 align_object_offset(nonstatic_oop_map_size()) :
2930 nonstatic_oop_map_size());
2931
2932 int n = 0;
2933 n += (sz->_methods_array_bytes = sz->count_array(methods()));
2934 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
2935 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
2936 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
2937 n += (sz->_fields_bytes = sz->count_array(fields()));
2938 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
2939 sz->_ro_bytes += n;
2940
2941 const ConstantPool* cp = constants();
2942 if (cp) {
2943 cp->collect_statistics(sz);
2944 }
2945
2946 const Annotations* anno = annotations();
2947 if (anno) {
2948 anno->collect_statistics(sz);
2949 }
2950
2951 const Array<Method*>* methods_array = methods();
2952 if (methods()) {
2953 for (int i = 0; i < methods_array->length(); i++) {
2954 Method* method = methods_array->at(i);
2955 if (method) {
2956 sz->_method_count ++;
2957 method->collect_statistics(sz);
2958 }
2959 }
2960 }
2961 }
2962 #endif // INCLUDE_SERVICES
2963
2964 // Verification
2965
2966 class VerifyFieldClosure: public OopClosure {
2967 protected:
2968 template <class T> void do_oop_work(T* p) {
2969 oop obj = oopDesc::load_decode_heap_oop(p);
2970 if (!obj->is_oop_or_null()) {
2971 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
2972 Universe::print();
2973 guarantee(false, "boom");
2974 }
2975 }
2976 public:
2977 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
2978 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2979 };
2980
2981 void InstanceKlass::verify_on(outputStream* st) {
2982 #ifndef PRODUCT
2983 // Avoid redundant verifies, this really should be in product.
2984 if (_verify_count == Universe::verify_count()) return;
2985 _verify_count = Universe::verify_count();
2986 #endif
2987
2988 // Verify Klass
2989 Klass::verify_on(st);
2990
2991 // Verify that klass is present in ClassLoaderData
2992 guarantee(class_loader_data()->contains_klass(this),
2993 "this class isn't found in class loader data");
2994
2995 // Verify vtables
2996 if (is_linked()) {
2997 ResourceMark rm;
2998 // $$$ This used to be done only for m/s collections. Doing it
2999 // always seemed a valid generalization. (DLD -- 6/00)
3000 vtable()->verify(st);
3001 }
3002
3003 // Verify first subklass
3004 if (subklass() != NULL) {
3005 guarantee(subklass()->is_klass(), "should be klass");
3006 }
3007
3008 // Verify siblings
3009 Klass* super = this->super();
3010 Klass* sib = next_sibling();
3011 if (sib != NULL) {
3012 if (sib == this) {
3013 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3014 }
3015
3016 guarantee(sib->is_klass(), "should be klass");
3017 guarantee(sib->super() == super, "siblings should have same superklass");
3018 }
3019
3020 // Verify implementor fields
3021 Klass* im = implementor();
3022 if (im != NULL) {
3023 guarantee(is_interface(), "only interfaces should have implementor set");
3024 guarantee(im->is_klass(), "should be klass");
3025 guarantee(!im->is_interface() || im == this,
3026 "implementors cannot be interfaces");
3027 }
3028
3029 // Verify local interfaces
3030 if (local_interfaces()) {
3031 Array<Klass*>* local_interfaces = this->local_interfaces();
3032 for (int j = 0; j < local_interfaces->length(); j++) {
3033 Klass* e = local_interfaces->at(j);
3034 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3035 }
3036 }
3037
3038 // Verify transitive interfaces
3039 if (transitive_interfaces() != NULL) {
3040 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3041 for (int j = 0; j < transitive_interfaces->length(); j++) {
3042 Klass* e = transitive_interfaces->at(j);
3043 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3044 }
3045 }
3046
3047 // Verify methods
3048 if (methods() != NULL) {
3049 Array<Method*>* methods = this->methods();
3050 for (int j = 0; j < methods->length(); j++) {
3051 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3052 }
3053 for (int j = 0; j < methods->length() - 1; j++) {
3054 Method* m1 = methods->at(j);
3055 Method* m2 = methods->at(j + 1);
3056 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3057 }
3058 }
3059
3060 // Verify method ordering
3061 if (method_ordering() != NULL) {
3062 Array<int>* method_ordering = this->method_ordering();
3063 int length = method_ordering->length();
3064 if (JvmtiExport::can_maintain_original_method_order() ||
3065 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3066 guarantee(length == methods()->length(), "invalid method ordering length");
3067 jlong sum = 0;
3068 for (int j = 0; j < length; j++) {
3069 int original_index = method_ordering->at(j);
3070 guarantee(original_index >= 0, "invalid method ordering index");
3071 guarantee(original_index < length, "invalid method ordering index");
3072 sum += original_index;
3073 }
3074 // Verify sum of indices 0,1,...,length-1
3075 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3076 } else {
3077 guarantee(length == 0, "invalid method ordering length");
3078 }
3079 }
3080
3081 // Verify default methods
3082 if (default_methods() != NULL) {
3083 Array<Method*>* methods = this->default_methods();
3084 for (int j = 0; j < methods->length(); j++) {
3085 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3086 }
3087 for (int j = 0; j < methods->length() - 1; j++) {
3088 Method* m1 = methods->at(j);
3089 Method* m2 = methods->at(j + 1);
3090 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3091 }
3092 }
3093
3094 // Verify JNI static field identifiers
3095 if (jni_ids() != NULL) {
3096 jni_ids()->verify(this);
3097 }
3098
3099 // Verify other fields
3100 if (array_klasses() != NULL) {
3101 guarantee(array_klasses()->is_klass(), "should be klass");
3102 }
3103 if (constants() != NULL) {
3104 guarantee(constants()->is_constantPool(), "should be constant pool");
3105 }
3106 const Klass* host = host_klass();
3107 if (host != NULL) {
3108 guarantee(host->is_klass(), "should be klass");
3109 }
3110 }
3111
3112 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3113 Klass::oop_verify_on(obj, st);
3114 VerifyFieldClosure blk;
3115 obj->oop_iterate_no_header(&blk);
3116 }
3117
3118
3119 // JNIid class for jfieldIDs only
3120 // Note to reviewers:
3121 // These JNI functions are just moved over to column 1 and not changed
3122 // in the compressed oops workspace.
3123 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3124 _holder = holder;
3125 _offset = offset;
3126 _next = next;
3127 debug_only(_is_static_field_id = false;)
3128 }
3129
3130
3131 JNIid* JNIid::find(int offset) {
3132 JNIid* current = this;
3133 while (current != NULL) {
3134 if (current->offset() == offset) return current;
3135 current = current->next();
3136 }
3137 return NULL;
3138 }
3139
3140 void JNIid::deallocate(JNIid* current) {
3141 while (current != NULL) {
3142 JNIid* next = current->next();
3143 delete current;
3144 current = next;
3145 }
3146 }
3147
3148
3149 void JNIid::verify(Klass* holder) {
3150 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3151 int end_field_offset;
3152 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3153
3154 JNIid* current = this;
3155 while (current != NULL) {
3156 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3157 #ifdef ASSERT
3158 int o = current->offset();
3159 if (current->is_static_field_id()) {
3160 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3161 }
3162 #endif
3163 current = current->next();
3164 }
3165 }
3166
3167
3168 #ifdef ASSERT
3169 void InstanceKlass::set_init_state(ClassState state) {
3170 bool good_state = is_shared() ? (_init_state <= state)
3171 : (_init_state < state);
3172 assert(good_state || state == allocated, "illegal state transition");
3173 _init_state = (u1)state;
3174 }
3175 #endif
3176
3177
3178 // RedefineClasses() support for previous versions:
3179
3180 // Purge previous versions
3181 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3182 if (ik->previous_versions() != NULL) {
3183 // This klass has previous versions so see what we can cleanup
3184 // while it is safe to do so.
3185
3186 int deleted_count = 0; // leave debugging breadcrumbs
3187 int live_count = 0;
3188 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3189 ClassLoaderData::the_null_class_loader_data() :
3190 ik->class_loader_data();
3191
3192 // RC_TRACE macro has an embedded ResourceMark
3193 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3194 ik->external_name(), ik->previous_versions()->length()));
3195
3196 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3197 // check the previous versions array
3198 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3199 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3200 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3201
3202 ConstantPool* pvcp = cp_ref;
3203 if (!pvcp->on_stack()) {
3204 // If the constant pool isn't on stack, none of the methods
3205 // are executing. Delete all the methods, the constant pool and
3206 // and this previous version node.
3207 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3208 if (method_refs != NULL) {
3209 for (int j = method_refs->length() - 1; j >= 0; j--) {
3210 Method* method = method_refs->at(j);
3211 assert(method != NULL, "method ref was unexpectedly cleared");
3212 method_refs->remove_at(j);
3213 // method will be freed with associated class.
3214 }
3215 }
3216 // Remove the constant pool
3217 delete pv_node;
3218 // Since we are traversing the array backwards, we don't have to
3219 // do anything special with the index.
3220 ik->previous_versions()->remove_at(i);
3221 deleted_count++;
3222 continue;
3223 } else {
3224 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3225 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3226 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3227 live_count++;
3228 }
3229
3230 // At least one method is live in this previous version, clean out
3231 // the others or mark them as obsolete.
3232 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3233 if (method_refs != NULL) {
3234 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3235 method_refs->length()));
3236 for (int j = method_refs->length() - 1; j >= 0; j--) {
3237 Method* method = method_refs->at(j);
3238 assert(method != NULL, "method ref was unexpectedly cleared");
3239
3240 // Remove the emcp method if it's not executing
3241 // If it's been made obsolete by a redefinition of a non-emcp
3242 // method, mark it as obsolete but leave it to clean up later.
3243 if (!method->on_stack()) {
3244 method_refs->remove_at(j);
3245 } else if (emcp_method_count == 0) {
3246 method->set_is_obsolete();
3247 } else {
3248 // RC_TRACE macro has an embedded ResourceMark
3249 RC_TRACE(0x00000200,
3250 ("purge: %s(%s): prev method @%d in version @%d is alive",
3251 method->name()->as_C_string(),
3252 method->signature()->as_C_string(), j, i));
3253 if (method->method_data() != NULL) {
3254 // Clean out any weak method links
3255 method->method_data()->clean_weak_method_links();
3256 }
3257 }
3258 }
3259 }
3260 }
3261 assert(ik->previous_versions()->length() == live_count, "sanity check");
3262 RC_TRACE(0x00000200,
3263 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3264 deleted_count));
3265 }
3266
3267 Array<Method*>* methods = ik->methods();
3268 int num_methods = methods->length();
3269 for (int index2 = 0; index2 < num_methods; ++index2) {
3270 if (methods->at(index2)->method_data() != NULL) {
3271 methods->at(index2)->method_data()->clean_weak_method_links();
3272 }
3273 }
3274 }
3275
3276 // External interface for use during class unloading.
3277 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3278 // Call with >0 emcp methods since they are not currently being redefined.
3279 purge_previous_versions_internal(ik, 1);
3280 }
3281
3282
3283 // Potentially add an information node that contains pointers to the
3284 // interesting parts of the previous version of the_class.
3285 // This is also where we clean out any unused references.
3286 // Note that while we delete nodes from the _previous_versions
3287 // array, we never delete the array itself until the klass is
3288 // unloaded. The has_been_redefined() query depends on that fact.
3289 //
3290 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3291 BitMap* emcp_methods, int emcp_method_count) {
3292 assert(Thread::current()->is_VM_thread(),
3293 "only VMThread can add previous versions");
3294
3295 if (_previous_versions == NULL) {
3296 // This is the first previous version so make some space.
3297 // Start with 2 elements under the assumption that the class
3298 // won't be redefined much.
3299 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3300 GrowableArray<PreviousVersionNode *>(2, true);
3301 }
3302
3303 ConstantPool* cp_ref = ikh->constants();
3304
3305 // RC_TRACE macro has an embedded ResourceMark
3306 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3307 "on_stack=%d",
3308 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3309 cp_ref->on_stack()));
3310
3311 // If the constant pool for this previous version of the class
3312 // is not marked as being on the stack, then none of the methods
3313 // in this previous version of the class are on the stack so
3314 // we don't need to create a new PreviousVersionNode. However,
3315 // we still need to examine older previous versions below.
3316 Array<Method*>* old_methods = ikh->methods();
3317
3318 if (cp_ref->on_stack()) {
3319 PreviousVersionNode * pv_node = NULL;
3320 if (emcp_method_count == 0) {
3321 // non-shared ConstantPool gets a reference
3322 pv_node = new PreviousVersionNode(cp_ref, NULL);
3323 RC_TRACE(0x00000400,
3324 ("add: all methods are obsolete; flushing any EMCP refs"));
3325 } else {
3326 int local_count = 0;
3327 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3328 GrowableArray<Method*>(emcp_method_count, true);
3329 for (int i = 0; i < old_methods->length(); i++) {
3330 if (emcp_methods->at(i)) {
3331 // this old method is EMCP. Save it only if it's on the stack
3332 Method* old_method = old_methods->at(i);
3333 if (old_method->on_stack()) {
3334 method_refs->append(old_method);
3335 }
3336 if (++local_count >= emcp_method_count) {
3337 // no more EMCP methods so bail out now
3338 break;
3339 }
3340 }
3341 }
3342 // non-shared ConstantPool gets a reference
3343 pv_node = new PreviousVersionNode(cp_ref, method_refs);
3344 }
3345 // append new previous version.
3346 _previous_versions->append(pv_node);
3347 }
3348
3349 // Since the caller is the VMThread and we are at a safepoint, this
3350 // is a good time to clear out unused references.
3351
3352 RC_TRACE(0x00000400, ("add: previous version length=%d",
3353 _previous_versions->length()));
3354
3355 // Purge previous versions not executing on the stack
3356 purge_previous_versions_internal(this, emcp_method_count);
3357
3358 int obsolete_method_count = old_methods->length() - emcp_method_count;
3359
3360 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3361 _previous_versions->length() > 0) {
3362 // We have a mix of obsolete and EMCP methods so we have to
3363 // clear out any matching EMCP method entries the hard way.
3364 int local_count = 0;
3365 for (int i = 0; i < old_methods->length(); i++) {
3366 if (!emcp_methods->at(i)) {
3367 // only obsolete methods are interesting
3368 Method* old_method = old_methods->at(i);
3369 Symbol* m_name = old_method->name();
3370 Symbol* m_signature = old_method->signature();
3371
3372 // we might not have added the last entry
3373 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3374 // check the previous versions array for non executing obsolete methods
3375 PreviousVersionNode * pv_node = _previous_versions->at(j);
3376
3377 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3378 if (method_refs == NULL) {
3379 // We have run into a PreviousVersion generation where
3380 // all methods were made obsolete during that generation's
3381 // RedefineClasses() operation. At the time of that
3382 // operation, all EMCP methods were flushed so we don't
3383 // have to go back any further.
3384 //
3385 // A NULL method_refs is different than an empty method_refs.
3386 // We cannot infer any optimizations about older generations
3387 // from an empty method_refs for the current generation.
3388 break;
3389 }
3390
3391 for (int k = method_refs->length() - 1; k >= 0; k--) {
3392 Method* method = method_refs->at(k);
3393
3394 if (!method->is_obsolete() &&
3395 method->name() == m_name &&
3396 method->signature() == m_signature) {
3397 // The current RedefineClasses() call has made all EMCP
3398 // versions of this method obsolete so mark it as obsolete
3399 // and remove the reference.
3400 RC_TRACE(0x00000400,
3401 ("add: %s(%s): flush obsolete method @%d in version @%d",
3402 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3403
3404 method->set_is_obsolete();
3405 // Leave obsolete methods on the previous version list to
3406 // clean up later.
3407 break;
3408 }
3409 }
3410
3411 // The previous loop may not find a matching EMCP method, but
3412 // that doesn't mean that we can optimize and not go any
3413 // further back in the PreviousVersion generations. The EMCP
3414 // method for this generation could have already been deleted,
3415 // but there still may be an older EMCP method that has not
3416 // been deleted.
3417 }
3418
3419 if (++local_count >= obsolete_method_count) {
3420 // no more obsolete methods so bail out now
3421 break;
3422 }
3423 }
3424 }
3425 }
3426 } // end add_previous_version()
3427
3428
3429 // Determine if InstanceKlass has a previous version.
3430 bool InstanceKlass::has_previous_version() const {
3431 return (_previous_versions != NULL && _previous_versions->length() > 0);
3432 } // end has_previous_version()
3433
3434
3435 Method* InstanceKlass::method_with_idnum(int idnum) {
3436 Method* m = NULL;
3437 if (idnum < methods()->length()) {
3438 m = methods()->at(idnum);
3439 }
3440 if (m == NULL || m->method_idnum() != idnum) {
3441 for (int index = 0; index < methods()->length(); ++index) {
3442 m = methods()->at(index);
3443 if (m->method_idnum() == idnum) {
3444 return m;
3445 }
3446 }
3447 // None found, return null for the caller to handle.
3448 return NULL;
3449 }
3450 return m;
3451 }
3452
3453 jint InstanceKlass::get_cached_class_file_len() {
3454 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3455 }
3456
3457 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3458 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3459 }
3460
3461
3462 // Construct a PreviousVersionNode entry for the array hung off
3463 // the InstanceKlass.
3464 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3465 GrowableArray<Method*>* prev_EMCP_methods) {
3466
3467 _prev_constant_pool = prev_constant_pool;
3468 _prev_EMCP_methods = prev_EMCP_methods;
3469 }
3470
3471
3472 // Destroy a PreviousVersionNode
3473 PreviousVersionNode::~PreviousVersionNode() {
3474 if (_prev_constant_pool != NULL) {
3475 _prev_constant_pool = NULL;
3476 }
3477
3478 if (_prev_EMCP_methods != NULL) {
3479 delete _prev_EMCP_methods;
3480 }
3481 }
3482
3483 // Construct a helper for walking the previous versions array
3484 PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) {
3485 _thread = thread;
3486 _previous_versions = ik->previous_versions();
3487 _current_index = 0;
3488 _current_p = NULL;
3489 _current_constant_pool_handle = constantPoolHandle(thread, ik->constants());
3490 }
3491
3492
3493 // Return the interesting information for the next previous version
3494 // of the klass. Returns NULL if there are no more previous versions.
3495 PreviousVersionNode* PreviousVersionWalker::next_previous_version() {
3496 if (_previous_versions == NULL) {
3497 // no previous versions so nothing to return
3498 return NULL;
3499 }
3500
3501 _current_p = NULL; // reset to NULL
3502 _current_constant_pool_handle = NULL;
3503
3504 int length = _previous_versions->length();
3505
3506 while (_current_index < length) {
3507 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3508
3509 // Save a handle to the constant pool for this previous version,
3510 // which keeps all the methods from being deallocated.
3511 _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool());
3512 _current_p = pv_node;
3513 return pv_node;
3514 }
3515
3516 return NULL;
3517 } // end next_previous_version()