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/metadataFactory.hpp"
39 #include "memory/oopFactory.hpp"
40 #include "oops/fieldStreams.hpp"
41 #include "oops/instanceClassLoaderKlass.hpp"
42 #include "oops/instanceKlass.hpp"
43 #include "oops/instanceMirrorKlass.hpp"
44 #include "oops/instanceOop.hpp"
45 #include "oops/klass.inline.hpp"
46 #include "oops/method.hpp"
47 #include "oops/oop.inline.hpp"
48 #include "oops/symbol.hpp"
49 #include "prims/jvmtiExport.hpp"
50 #include "prims/jvmtiRedefineClassesTrace.hpp"
51 #include "prims/jvmtiRedefineClasses.hpp"
52 #include "prims/jvmtiThreadState.hpp"
53 #include "prims/methodComparator.hpp"
54 #include "runtime/fieldDescriptor.hpp"
55 #include "runtime/handles.inline.hpp"
56 #include "runtime/javaCalls.hpp"
57 #include "runtime/mutexLocker.hpp"
58 #include "runtime/orderAccess.inline.hpp"
59 #include "runtime/thread.inline.hpp"
60 #include "services/classLoadingService.hpp"
61 #include "services/threadService.hpp"
62 #include "utilities/dtrace.hpp"
63 #include "utilities/macros.hpp"
64 #if INCLUDE_ALL_GCS
65 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
66 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
67 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
68 #include "gc_implementation/g1/g1RemSet.inline.hpp"
69 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
70 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
71 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
72 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
73 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
74 #include "oops/oop.pcgc.inline.hpp"
75 #endif // INCLUDE_ALL_GCS
76 #ifdef COMPILER1
77 #include "c1/c1_Compiler.hpp"
78 #endif
79
80 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
81
82 #ifdef DTRACE_ENABLED
83
84
85 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
86 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
87 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
88 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
89 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
90 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
91 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
92 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
93 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
94 { \
95 char* data = NULL; \
96 int len = 0; \
97 Symbol* name = (clss)->name(); \
98 if (name != NULL) { \
99 data = (char*)name->bytes(); \
100 len = name->utf8_length(); \
101 } \
102 HOTSPOT_CLASS_INITIALIZATION_##type( \
103 data, len, (clss)->class_loader(), thread_type); \
104 }
105
106 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
107 { \
108 char* data = NULL; \
109 int len = 0; \
110 Symbol* name = (clss)->name(); \
111 if (name != NULL) { \
112 data = (char*)name->bytes(); \
113 len = name->utf8_length(); \
114 } \
115 HOTSPOT_CLASS_INITIALIZATION_##type( \
116 data, len, (clss)->class_loader(), thread_type, wait); \
117 }
118
119 #else // ndef DTRACE_ENABLED
120
121 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
122 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
123
124 #endif // ndef DTRACE_ENABLED
125
126 volatile int InstanceKlass::_total_instanceKlass_count = 0;
127
128 InstanceKlass* InstanceKlass::allocate_instance_klass(
129 ClassLoaderData* loader_data,
130 int vtable_len,
131 int itable_len,
132 int static_field_size,
133 int nonstatic_oop_map_size,
134 ReferenceType rt,
135 AccessFlags access_flags,
136 Symbol* name,
137 Klass* super_klass,
138 bool is_anonymous,
139 TRAPS) {
140
141 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
142 access_flags.is_interface(), is_anonymous);
143
144 // Allocation
145 InstanceKlass* ik;
146 if (rt == REF_NONE) {
147 if (name == vmSymbols::java_lang_Class()) {
148 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
149 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
150 access_flags, is_anonymous);
151 } else if (name == vmSymbols::java_lang_ClassLoader() ||
152 (SystemDictionary::ClassLoader_klass_loaded() &&
153 super_klass != NULL &&
154 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
155 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
156 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
157 access_flags, is_anonymous);
158 } else {
159 // normal class
160 ik = new (loader_data, size, THREAD) InstanceKlass(
161 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
162 access_flags, is_anonymous);
163 }
164 } else {
165 // reference klass
166 ik = new (loader_data, size, THREAD) InstanceRefKlass(
167 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
168 access_flags, is_anonymous);
169 }
170
171 // Check for pending exception before adding to the loader data and incrementing
172 // class count. Can get OOM here.
173 if (HAS_PENDING_EXCEPTION) {
174 return NULL;
175 }
176
177 // Add all classes to our internal class loader list here,
178 // including classes in the bootstrap (NULL) class loader.
179 loader_data->add_class(ik);
180
181 Atomic::inc(&_total_instanceKlass_count);
182 return ik;
183 }
184
185
186 // copy method ordering from resource area to Metaspace
187 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
188 if (m != NULL) {
189 // allocate a new array and copy contents (memcpy?)
190 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
191 for (int i = 0; i < m->length(); i++) {
192 _method_ordering->at_put(i, m->at(i));
193 }
194 } else {
195 _method_ordering = Universe::the_empty_int_array();
196 }
197 }
198
199 // create a new array of vtable_indices for default methods
200 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
201 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
202 assert(default_vtable_indices() == NULL, "only create once");
203 set_default_vtable_indices(vtable_indices);
204 return vtable_indices;
205 }
206
207 InstanceKlass::InstanceKlass(int vtable_len,
208 int itable_len,
209 int static_field_size,
210 int nonstatic_oop_map_size,
211 ReferenceType rt,
212 AccessFlags access_flags,
213 bool is_anonymous) {
214 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
215
216 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
217 access_flags.is_interface(), is_anonymous);
218
219 set_vtable_length(vtable_len);
220 set_itable_length(itable_len);
221 set_static_field_size(static_field_size);
222 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
223 set_access_flags(access_flags);
224 _misc_flags = 0; // initialize to zero
225 set_is_anonymous(is_anonymous);
226 assert(size() == iksize, "wrong size for object");
227
228 set_array_klasses(NULL);
229 set_methods(NULL);
230 set_method_ordering(NULL);
231 set_default_methods(NULL);
232 set_default_vtable_indices(NULL);
233 set_local_interfaces(NULL);
234 set_transitive_interfaces(NULL);
235 init_implementor();
236 set_fields(NULL, 0);
237 set_constants(NULL);
238 set_class_loader_data(NULL);
239 set_source_file_name_index(0);
240 set_source_debug_extension(NULL, 0);
241 set_array_name(NULL);
242 set_inner_classes(NULL);
243 set_static_oop_field_count(0);
244 set_nonstatic_field_size(0);
245 set_is_marked_dependent(false);
246 set_init_state(InstanceKlass::allocated);
247 set_init_thread(NULL);
248 set_reference_type(rt);
249 set_oop_map_cache(NULL);
250 set_jni_ids(NULL);
251 set_osr_nmethods_head(NULL);
252 set_breakpoints(NULL);
253 init_previous_versions();
254 set_generic_signature_index(0);
255 release_set_methods_jmethod_ids(NULL);
256 set_annotations(NULL);
257 set_jvmti_cached_class_field_map(NULL);
258 set_initial_method_idnum(0);
259 _dependencies = NULL;
260 set_jvmti_cached_class_field_map(NULL);
261 set_cached_class_file(NULL);
262 set_initial_method_idnum(0);
263 set_minor_version(0);
264 set_major_version(0);
265 NOT_PRODUCT(_verify_count = 0;)
266
267 // initialize the non-header words to zero
268 intptr_t* p = (intptr_t*)this;
269 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
270 p[index] = NULL_WORD;
271 }
272
273 // Set temporary value until parseClassFile updates it with the real instance
274 // size.
275 set_layout_helper(Klass::instance_layout_helper(0, true));
276 }
277
278
279 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
280 Array<Method*>* methods) {
281 if (methods != NULL && methods != Universe::the_empty_method_array() &&
282 !methods->is_shared()) {
283 for (int i = 0; i < methods->length(); i++) {
284 Method* method = methods->at(i);
285 if (method == NULL) continue; // maybe null if error processing
286 // Only want to delete methods that are not executing for RedefineClasses.
287 // The previous version will point to them so they're not totally dangling
288 assert (!method->on_stack(), "shouldn't be called with methods on stack");
289 MetadataFactory::free_metadata(loader_data, method);
290 }
291 MetadataFactory::free_array<Method*>(loader_data, methods);
292 }
293 }
294
295 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
296 Klass* super_klass,
297 Array<Klass*>* local_interfaces,
298 Array<Klass*>* transitive_interfaces) {
299 // Only deallocate transitive interfaces if not empty, same as super class
300 // or same as local interfaces. See code in parseClassFile.
301 Array<Klass*>* ti = transitive_interfaces;
302 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
303 // check that the interfaces don't come from super class
304 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
305 InstanceKlass::cast(super_klass)->transitive_interfaces();
306 if (ti != sti && ti != NULL && !ti->is_shared()) {
307 MetadataFactory::free_array<Klass*>(loader_data, ti);
308 }
309 }
310
311 // local interfaces can be empty
312 if (local_interfaces != Universe::the_empty_klass_array() &&
313 local_interfaces != NULL && !local_interfaces->is_shared()) {
314 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
315 }
316 }
317
318 // This function deallocates the metadata and C heap pointers that the
319 // InstanceKlass points to.
320 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
321
322 // Orphan the mirror first, CMS thinks it's still live.
323 if (java_mirror() != NULL) {
324 java_lang_Class::set_klass(java_mirror(), NULL);
325 }
326
327 // Need to take this class off the class loader data list.
328 loader_data->remove_class(this);
329
330 // The array_klass for this class is created later, after error handling.
331 // For class redefinition, we keep the original class so this scratch class
332 // doesn't have an array class. Either way, assert that there is nothing
333 // to deallocate.
334 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
335
336 // Release C heap allocated data that this might point to, which includes
337 // reference counting symbol names.
338 release_C_heap_structures();
339
340 deallocate_methods(loader_data, methods());
341 set_methods(NULL);
342
343 if (method_ordering() != NULL &&
344 method_ordering() != Universe::the_empty_int_array() &&
345 !method_ordering()->is_shared()) {
346 MetadataFactory::free_array<int>(loader_data, method_ordering());
347 }
348 set_method_ordering(NULL);
349
350 // default methods can be empty
351 if (default_methods() != NULL &&
352 default_methods() != Universe::the_empty_method_array() &&
353 !default_methods()->is_shared()) {
354 MetadataFactory::free_array<Method*>(loader_data, default_methods());
355 }
356 // Do NOT deallocate the default methods, they are owned by superinterfaces.
357 set_default_methods(NULL);
358
359 // default methods vtable indices can be empty
360 if (default_vtable_indices() != NULL &&
361 !default_vtable_indices()->is_shared()) {
362 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
363 }
364 set_default_vtable_indices(NULL);
365
366
367 // This array is in Klass, but remove it with the InstanceKlass since
368 // this place would be the only caller and it can share memory with transitive
369 // interfaces.
370 if (secondary_supers() != NULL &&
371 secondary_supers() != Universe::the_empty_klass_array() &&
372 secondary_supers() != transitive_interfaces() &&
373 !secondary_supers()->is_shared()) {
374 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
375 }
376 set_secondary_supers(NULL);
377
378 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
379 set_transitive_interfaces(NULL);
380 set_local_interfaces(NULL);
381
382 if (fields() != NULL && !fields()->is_shared()) {
383 MetadataFactory::free_array<jushort>(loader_data, fields());
384 }
385 set_fields(NULL, 0);
386
387 // If a method from a redefined class is using this constant pool, don't
388 // delete it, yet. The new class's previous version will point to this.
389 if (constants() != NULL) {
390 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
391 if (!constants()->is_shared()) {
392 MetadataFactory::free_metadata(loader_data, constants());
393 }
394 set_constants(NULL);
395 }
396
397 if (inner_classes() != NULL &&
398 inner_classes() != Universe::the_empty_short_array() &&
399 !inner_classes()->is_shared()) {
400 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
401 }
402 set_inner_classes(NULL);
403
404 // We should deallocate the Annotations instance if it's not in shared spaces.
405 if (annotations() != NULL && !annotations()->is_shared()) {
406 MetadataFactory::free_metadata(loader_data, annotations());
407 }
408 set_annotations(NULL);
409 }
410
411 bool InstanceKlass::should_be_initialized() const {
412 return !is_initialized();
413 }
414
415 klassVtable* InstanceKlass::vtable() const {
416 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
417 }
418
419 klassItable* InstanceKlass::itable() const {
420 return new klassItable(instanceKlassHandle(this));
421 }
422
423 void InstanceKlass::eager_initialize(Thread *thread) {
424 if (!EagerInitialization) return;
425
426 if (this->is_not_initialized()) {
427 // abort if the the class has a class initializer
428 if (this->class_initializer() != NULL) return;
429
430 // abort if it is java.lang.Object (initialization is handled in genesis)
431 Klass* super = this->super();
432 if (super == NULL) return;
433
434 // abort if the super class should be initialized
435 if (!InstanceKlass::cast(super)->is_initialized()) return;
436
437 // call body to expose the this pointer
438 instanceKlassHandle this_k(thread, this);
439 eager_initialize_impl(this_k);
440 }
441 }
442
443 // JVMTI spec thinks there are signers and protection domain in the
444 // instanceKlass. These accessors pretend these fields are there.
445 // The hprof specification also thinks these fields are in InstanceKlass.
446 oop InstanceKlass::protection_domain() const {
447 // return the protection_domain from the mirror
448 return java_lang_Class::protection_domain(java_mirror());
449 }
450
451 // To remove these from requires an incompatible change and CCC request.
452 objArrayOop InstanceKlass::signers() const {
453 // return the signers from the mirror
454 return java_lang_Class::signers(java_mirror());
455 }
456
457 oop InstanceKlass::init_lock() const {
458 // return the init lock from the mirror
459 oop lock = java_lang_Class::init_lock(java_mirror());
460 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
461 "only fully initialized state can have a null lock");
462 return lock;
463 }
464
465 // Set the initialization lock to null so the object can be GC'ed. Any racing
466 // threads to get this lock will see a null lock and will not lock.
467 // That's okay because they all check for initialized state after getting
468 // the lock and return.
469 void InstanceKlass::fence_and_clear_init_lock() {
470 // make sure previous stores are all done, notably the init_state.
471 OrderAccess::storestore();
472 java_lang_Class::set_init_lock(java_mirror(), NULL);
473 assert(!is_not_initialized(), "class must be initialized now");
474 }
475
476 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
477 EXCEPTION_MARK;
478 oop init_lock = this_k->init_lock();
479 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
480
481 // abort if someone beat us to the initialization
482 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized()
483
484 ClassState old_state = this_k->init_state();
485 link_class_impl(this_k, true, THREAD);
486 if (HAS_PENDING_EXCEPTION) {
487 CLEAR_PENDING_EXCEPTION;
488 // Abort if linking the class throws an exception.
489
490 // Use a test to avoid redundantly resetting the state if there's
491 // no change. Set_init_state() asserts that state changes make
492 // progress, whereas here we might just be spinning in place.
493 if( old_state != this_k->_init_state )
494 this_k->set_init_state (old_state);
495 } else {
496 // linking successfull, mark class as initialized
497 this_k->set_init_state (fully_initialized);
498 this_k->fence_and_clear_init_lock();
499 // trace
500 if (TraceClassInitialization) {
501 ResourceMark rm(THREAD);
502 tty->print_cr("[Initialized %s without side effects]", this_k->external_name());
503 }
504 }
505 }
506
507
508 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
509 // process. The step comments refers to the procedure described in that section.
510 // Note: implementation moved to static method to expose the this pointer.
511 void InstanceKlass::initialize(TRAPS) {
512 if (this->should_be_initialized()) {
513 HandleMark hm(THREAD);
514 instanceKlassHandle this_k(THREAD, this);
515 initialize_impl(this_k, CHECK);
516 // Note: at this point the class may be initialized
517 // OR it may be in the state of being initialized
518 // in case of recursive initialization!
519 } else {
520 assert(is_initialized(), "sanity check");
521 }
522 }
523
524
525 bool InstanceKlass::verify_code(
526 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
527 // 1) Verify the bytecodes
528 Verifier::Mode mode =
529 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
530 return Verifier::verify(this_k, mode, this_k->should_verify_class(), CHECK_false);
531 }
532
533
534 // Used exclusively by the shared spaces dump mechanism to prevent
535 // classes mapped into the shared regions in new VMs from appearing linked.
536
537 void InstanceKlass::unlink_class() {
538 assert(is_linked(), "must be linked");
539 _init_state = loaded;
540 }
541
542 void InstanceKlass::link_class(TRAPS) {
543 assert(is_loaded(), "must be loaded");
544 if (!is_linked()) {
545 HandleMark hm(THREAD);
546 instanceKlassHandle this_k(THREAD, this);
547 link_class_impl(this_k, true, CHECK);
548 }
549 }
550
551 // Called to verify that a class can link during initialization, without
552 // throwing a VerifyError.
553 bool InstanceKlass::link_class_or_fail(TRAPS) {
554 assert(is_loaded(), "must be loaded");
555 if (!is_linked()) {
556 HandleMark hm(THREAD);
557 instanceKlassHandle this_k(THREAD, this);
558 link_class_impl(this_k, false, CHECK_false);
559 }
560 return is_linked();
561 }
562
563 bool InstanceKlass::link_class_impl(
564 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
565 // check for error state
566 if (this_k->is_in_error_state()) {
567 ResourceMark rm(THREAD);
568 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
569 this_k->external_name(), false);
570 }
571 // return if already verified
572 if (this_k->is_linked()) {
573 return true;
574 }
575
576 // Timing
577 // timer handles recursion
578 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
579 JavaThread* jt = (JavaThread*)THREAD;
580
581 // link super class before linking this class
582 instanceKlassHandle super(THREAD, this_k->super());
583 if (super.not_null()) {
584 if (super->is_interface()) { // check if super class is an interface
585 ResourceMark rm(THREAD);
586 Exceptions::fthrow(
587 THREAD_AND_LOCATION,
588 vmSymbols::java_lang_IncompatibleClassChangeError(),
589 "class %s has interface %s as super class",
590 this_k->external_name(),
591 super->external_name()
592 );
593 return false;
594 }
595
596 link_class_impl(super, throw_verifyerror, CHECK_false);
597 }
598
599 // link all interfaces implemented by this class before linking this class
600 Array<Klass*>* interfaces = this_k->local_interfaces();
601 int num_interfaces = interfaces->length();
602 for (int index = 0; index < num_interfaces; index++) {
603 HandleMark hm(THREAD);
604 instanceKlassHandle ih(THREAD, interfaces->at(index));
605 link_class_impl(ih, throw_verifyerror, CHECK_false);
606 }
607
608 // in case the class is linked in the process of linking its superclasses
609 if (this_k->is_linked()) {
610 return true;
611 }
612
613 // trace only the link time for this klass that includes
614 // the verification time
615 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
616 ClassLoader::perf_class_link_selftime(),
617 ClassLoader::perf_classes_linked(),
618 jt->get_thread_stat()->perf_recursion_counts_addr(),
619 jt->get_thread_stat()->perf_timers_addr(),
620 PerfClassTraceTime::CLASS_LINK);
621
622 // verification & rewriting
623 {
624 oop init_lock = this_k->init_lock();
625 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
626 // rewritten will have been set if loader constraint error found
627 // on an earlier link attempt
628 // don't verify or rewrite if already rewritten
629
630 if (!this_k->is_linked()) {
631 if (!this_k->is_rewritten()) {
632 {
633 // Timer includes any side effects of class verification (resolution,
634 // etc), but not recursive entry into verify_code().
635 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
636 ClassLoader::perf_class_verify_selftime(),
637 ClassLoader::perf_classes_verified(),
638 jt->get_thread_stat()->perf_recursion_counts_addr(),
639 jt->get_thread_stat()->perf_timers_addr(),
640 PerfClassTraceTime::CLASS_VERIFY);
641 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
642 if (!verify_ok) {
643 return false;
644 }
645 }
646
647 // Just in case a side-effect of verify linked this class already
648 // (which can sometimes happen since the verifier loads classes
649 // using custom class loaders, which are free to initialize things)
650 if (this_k->is_linked()) {
651 return true;
652 }
653
654 // also sets rewritten
655 this_k->rewrite_class(CHECK_false);
656 }
657
658 // relocate jsrs and link methods after they are all rewritten
659 this_k->link_methods(CHECK_false);
660
661 // Initialize the vtable and interface table after
662 // methods have been rewritten since rewrite may
663 // fabricate new Method*s.
664 // also does loader constraint checking
665 if (!this_k()->is_shared()) {
666 ResourceMark rm(THREAD);
667 this_k->vtable()->initialize_vtable(true, CHECK_false);
668 this_k->itable()->initialize_itable(true, CHECK_false);
669 }
670 #ifdef ASSERT
671 else {
672 ResourceMark rm(THREAD);
673 this_k->vtable()->verify(tty, true);
674 // In case itable verification is ever added.
675 // this_k->itable()->verify(tty, true);
676 }
677 #endif
678 this_k->set_init_state(linked);
679 if (JvmtiExport::should_post_class_prepare()) {
680 Thread *thread = THREAD;
681 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
682 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
683 }
684 }
685 }
686 return true;
687 }
688
689
690 // Rewrite the byte codes of all of the methods of a class.
691 // The rewriter must be called exactly once. Rewriting must happen after
692 // verification but before the first method of the class is executed.
693 void InstanceKlass::rewrite_class(TRAPS) {
694 assert(is_loaded(), "must be loaded");
695 instanceKlassHandle this_k(THREAD, this);
696 if (this_k->is_rewritten()) {
697 assert(this_k()->is_shared(), "rewriting an unshared class?");
698 return;
699 }
700 Rewriter::rewrite(this_k, CHECK);
701 this_k->set_rewritten();
702 }
703
704 // Now relocate and link method entry points after class is rewritten.
705 // This is outside is_rewritten flag. In case of an exception, it can be
706 // executed more than once.
707 void InstanceKlass::link_methods(TRAPS) {
708 int len = methods()->length();
709 for (int i = len-1; i >= 0; i--) {
710 methodHandle m(THREAD, methods()->at(i));
711
712 // Set up method entry points for compiler and interpreter .
713 m->link_method(m, CHECK);
714
715 // This is for JVMTI and unrelated to relocator but the last thing we do
716 #ifdef ASSERT
717 if (StressMethodComparator) {
718 ResourceMark rm(THREAD);
719 static int nmc = 0;
720 for (int j = i; j >= 0 && j >= i-4; j--) {
721 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
722 bool z = MethodComparator::methods_EMCP(m(),
723 methods()->at(j));
724 if (j == i && !z) {
725 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
726 assert(z, "method must compare equal to itself");
727 }
728 }
729 }
730 #endif //ASSERT
731 }
732 }
733
734
735 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
736 // Make sure klass is linked (verified) before initialization
737 // A class could already be verified, since it has been reflected upon.
738 this_k->link_class(CHECK);
739
740 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_k()), -1);
741
742 bool wait = false;
743
744 // refer to the JVM book page 47 for description of steps
745 // Step 1
746 {
747 oop init_lock = this_k->init_lock();
748 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
749
750 Thread *self = THREAD; // it's passed the current thread
751
752 // Step 2
753 // If we were to use wait() instead of waitInterruptibly() then
754 // we might end up throwing IE from link/symbol resolution sites
755 // that aren't expected to throw. This would wreak havoc. See 6320309.
756 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
757 wait = true;
758 ol.waitUninterruptibly(CHECK);
759 }
760
761 // Step 3
762 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
763 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_k()), -1,wait);
764 return;
765 }
766
767 // Step 4
768 if (this_k->is_initialized()) {
769 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_k()), -1,wait);
770 return;
771 }
772
773 // Step 5
774 if (this_k->is_in_error_state()) {
775 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_k()), -1,wait);
776 ResourceMark rm(THREAD);
777 const char* desc = "Could not initialize class ";
778 const char* className = this_k->external_name();
779 size_t msglen = strlen(desc) + strlen(className) + 1;
780 char* message = NEW_RESOURCE_ARRAY(char, msglen);
781 if (NULL == message) {
782 // Out of memory: can't create detailed error message
783 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
784 } else {
785 jio_snprintf(message, msglen, "%s%s", desc, className);
786 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
787 }
788 }
789
790 // Step 6
791 this_k->set_init_state(being_initialized);
792 this_k->set_init_thread(self);
793 }
794
795 // Step 7
796 Klass* super_klass = this_k->super();
797 if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) {
798 super_klass->initialize(THREAD);
799
800 if (HAS_PENDING_EXCEPTION) {
801 Handle e(THREAD, PENDING_EXCEPTION);
802 CLEAR_PENDING_EXCEPTION;
803 {
804 EXCEPTION_MARK;
805 this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
806 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
807 }
808 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_k()), -1,wait);
809 THROW_OOP(e());
810 }
811 }
812
813 if (this_k->has_default_methods()) {
814 // Step 7.5: initialize any interfaces which have default methods
815 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
816 Klass* iface = this_k->local_interfaces()->at(i);
817 InstanceKlass* ik = InstanceKlass::cast(iface);
818 if (ik->has_default_methods() && ik->should_be_initialized()) {
819 ik->initialize(THREAD);
820
821 if (HAS_PENDING_EXCEPTION) {
822 Handle e(THREAD, PENDING_EXCEPTION);
823 CLEAR_PENDING_EXCEPTION;
824 {
825 EXCEPTION_MARK;
826 // Locks object, set state, and notify all waiting threads
827 this_k->set_initialization_state_and_notify(
828 initialization_error, THREAD);
829
830 // ignore any exception thrown, superclass initialization error is
831 // thrown below
832 CLEAR_PENDING_EXCEPTION;
833 }
834 DTRACE_CLASSINIT_PROBE_WAIT(
835 super__failed, InstanceKlass::cast(this_k()), -1, wait);
836 THROW_OOP(e());
837 }
838 }
839 }
840 }
841
842 // Step 8
843 {
844 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
845 JavaThread* jt = (JavaThread*)THREAD;
846 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_k()), -1,wait);
847 // Timer includes any side effects of class initialization (resolution,
848 // etc), but not recursive entry into call_class_initializer().
849 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
850 ClassLoader::perf_class_init_selftime(),
851 ClassLoader::perf_classes_inited(),
852 jt->get_thread_stat()->perf_recursion_counts_addr(),
853 jt->get_thread_stat()->perf_timers_addr(),
854 PerfClassTraceTime::CLASS_CLINIT);
855 this_k->call_class_initializer(THREAD);
856 }
857
858 // Step 9
859 if (!HAS_PENDING_EXCEPTION) {
860 this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
861 { ResourceMark rm(THREAD);
862 debug_only(this_k->vtable()->verify(tty, true);)
863 }
864 }
865 else {
866 // Step 10 and 11
867 Handle e(THREAD, PENDING_EXCEPTION);
868 CLEAR_PENDING_EXCEPTION;
869 // JVMTI has already reported the pending exception
870 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
871 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
872 {
873 EXCEPTION_MARK;
874 this_k->set_initialization_state_and_notify(initialization_error, THREAD);
875 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
876 // JVMTI has already reported the pending exception
877 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
878 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
879 }
880 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_k()), -1,wait);
881 if (e->is_a(SystemDictionary::Error_klass())) {
882 THROW_OOP(e());
883 } else {
884 JavaCallArguments args(e);
885 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
886 vmSymbols::throwable_void_signature(),
887 &args);
888 }
889 }
890 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_k()), -1,wait);
891 }
892
893
894 // Note: implementation moved to static method to expose the this pointer.
895 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
896 instanceKlassHandle kh(THREAD, this);
897 set_initialization_state_and_notify_impl(kh, state, CHECK);
898 }
899
900 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
901 oop init_lock = this_k->init_lock();
902 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
903 this_k->set_init_state(state);
904 this_k->fence_and_clear_init_lock();
905 ol.notify_all(CHECK);
906 }
907
908 // The embedded _implementor field can only record one implementor.
909 // When there are more than one implementors, the _implementor field
910 // is set to the interface Klass* itself. Following are the possible
911 // values for the _implementor field:
912 // NULL - no implementor
913 // implementor Klass* - one implementor
914 // self - more than one implementor
915 //
916 // The _implementor field only exists for interfaces.
917 void InstanceKlass::add_implementor(Klass* k) {
918 assert(Compile_lock->owned_by_self(), "");
919 assert(is_interface(), "not interface");
920 // Filter out my subinterfaces.
921 // (Note: Interfaces are never on the subklass list.)
922 if (InstanceKlass::cast(k)->is_interface()) return;
923
924 // Filter out subclasses whose supers already implement me.
925 // (Note: CHA must walk subclasses of direct implementors
926 // in order to locate indirect implementors.)
927 Klass* sk = InstanceKlass::cast(k)->super();
928 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
929 // We only need to check one immediate superclass, since the
930 // implements_interface query looks at transitive_interfaces.
931 // Any supers of the super have the same (or fewer) transitive_interfaces.
932 return;
933
934 Klass* ik = implementor();
935 if (ik == NULL) {
936 set_implementor(k);
937 } else if (ik != this) {
938 // There is already an implementor. Use itself as an indicator of
939 // more than one implementors.
940 set_implementor(this);
941 }
942
943 // The implementor also implements the transitive_interfaces
944 for (int index = 0; index < local_interfaces()->length(); index++) {
945 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
946 }
947 }
948
949 void InstanceKlass::init_implementor() {
950 if (is_interface()) {
951 set_implementor(NULL);
952 }
953 }
954
955
956 void InstanceKlass::process_interfaces(Thread *thread) {
957 // link this class into the implementors list of every interface it implements
958 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
959 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
960 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
961 assert(interf->is_interface(), "expected interface");
962 interf->add_implementor(this);
963 }
964 }
965
966 bool InstanceKlass::can_be_primary_super_slow() const {
967 if (is_interface())
968 return false;
969 else
970 return Klass::can_be_primary_super_slow();
971 }
972
973 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
974 // The secondaries are the implemented interfaces.
975 InstanceKlass* ik = InstanceKlass::cast(this);
976 Array<Klass*>* interfaces = ik->transitive_interfaces();
977 int num_secondaries = num_extra_slots + interfaces->length();
978 if (num_secondaries == 0) {
979 // Must share this for correct bootstrapping!
980 set_secondary_supers(Universe::the_empty_klass_array());
981 return NULL;
982 } else if (num_extra_slots == 0) {
983 // The secondary super list is exactly the same as the transitive interfaces.
984 // Redefine classes has to be careful not to delete this!
985 set_secondary_supers(interfaces);
986 return NULL;
987 } else {
988 // Copy transitive interfaces to a temporary growable array to be constructed
989 // into the secondary super list with extra slots.
990 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
991 for (int i = 0; i < interfaces->length(); i++) {
992 secondaries->push(interfaces->at(i));
993 }
994 return secondaries;
995 }
996 }
997
998 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
999 if (k->is_interface()) {
1000 return implements_interface(k);
1001 } else {
1002 return Klass::compute_is_subtype_of(k);
1003 }
1004 }
1005
1006 bool InstanceKlass::implements_interface(Klass* k) const {
1007 if (this == k) return true;
1008 assert(k->is_interface(), "should be an interface class");
1009 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1010 if (transitive_interfaces()->at(i) == k) {
1011 return true;
1012 }
1013 }
1014 return false;
1015 }
1016
1017 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1018 // Verify direct super interface
1019 if (this == k) return true;
1020 assert(k->is_interface(), "should be an interface class");
1021 for (int i = 0; i < local_interfaces()->length(); i++) {
1022 if (local_interfaces()->at(i) == k) {
1023 return true;
1024 }
1025 }
1026 return false;
1027 }
1028
1029 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1030 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1031 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1032 report_java_out_of_memory("Requested array size exceeds VM limit");
1033 JvmtiExport::post_array_size_exhausted();
1034 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1035 }
1036 int size = objArrayOopDesc::object_size(length);
1037 Klass* ak = array_klass(n, CHECK_NULL);
1038 KlassHandle h_ak (THREAD, ak);
1039 objArrayOop o =
1040 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1041 return o;
1042 }
1043
1044 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1045 if (TraceFinalizerRegistration) {
1046 tty->print("Registered ");
1047 i->print_value_on(tty);
1048 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
1049 }
1050 instanceHandle h_i(THREAD, i);
1051 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1052 JavaValue result(T_VOID);
1053 JavaCallArguments args(h_i);
1054 methodHandle mh (THREAD, Universe::finalizer_register_method());
1055 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1056 return h_i();
1057 }
1058
1059 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1060 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1061 int size = size_helper(); // Query before forming handle.
1062
1063 KlassHandle h_k(THREAD, this);
1064
1065 instanceOop i;
1066
1067 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1068 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1069 i = register_finalizer(i, CHECK_NULL);
1070 }
1071 return i;
1072 }
1073
1074 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1075 if (is_interface() || is_abstract()) {
1076 ResourceMark rm(THREAD);
1077 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1078 : vmSymbols::java_lang_InstantiationException(), external_name());
1079 }
1080 if (this == SystemDictionary::Class_klass()) {
1081 ResourceMark rm(THREAD);
1082 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1083 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1084 }
1085 }
1086
1087 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1088 instanceKlassHandle this_k(THREAD, this);
1089 return array_klass_impl(this_k, or_null, n, THREAD);
1090 }
1091
1092 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1093 if (this_k->array_klasses() == NULL) {
1094 if (or_null) return NULL;
1095
1096 ResourceMark rm;
1097 JavaThread *jt = (JavaThread *)THREAD;
1098 {
1099 // Atomic creation of array_klasses
1100 MutexLocker mc(Compile_lock, THREAD); // for vtables
1101 MutexLocker ma(MultiArray_lock, THREAD);
1102
1103 // Check if update has already taken place
1104 if (this_k->array_klasses() == NULL) {
1105 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1106 this_k->set_array_klasses(k);
1107 }
1108 }
1109 }
1110 // _this will always be set at this point
1111 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1112 if (or_null) {
1113 return oak->array_klass_or_null(n);
1114 }
1115 return oak->array_klass(n, CHECK_NULL);
1116 }
1117
1118 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1119 return array_klass_impl(or_null, 1, THREAD);
1120 }
1121
1122 void InstanceKlass::call_class_initializer(TRAPS) {
1123 instanceKlassHandle ik (THREAD, this);
1124 call_class_initializer_impl(ik, THREAD);
1125 }
1126
1127 static int call_class_initializer_impl_counter = 0; // for debugging
1128
1129 Method* InstanceKlass::class_initializer() {
1130 Method* clinit = find_method(
1131 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1132 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1133 return clinit;
1134 }
1135 return NULL;
1136 }
1137
1138 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1139 if (ReplayCompiles &&
1140 (ReplaySuppressInitializers == 1 ||
1141 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1142 // Hide the existence of the initializer for the purpose of replaying the compile
1143 return;
1144 }
1145
1146 methodHandle h_method(THREAD, this_k->class_initializer());
1147 assert(!this_k->is_initialized(), "we cannot initialize twice");
1148 if (TraceClassInitialization) {
1149 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1150 this_k->name()->print_value();
1151 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_k());
1152 }
1153 if (h_method() != NULL) {
1154 JavaCallArguments args; // No arguments
1155 JavaValue result(T_VOID);
1156 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1157 }
1158 }
1159
1160
1161 void InstanceKlass::mask_for(methodHandle method, int bci,
1162 InterpreterOopMap* entry_for) {
1163 // Dirty read, then double-check under a lock.
1164 if (_oop_map_cache == NULL) {
1165 // Otherwise, allocate a new one.
1166 MutexLocker x(OopMapCacheAlloc_lock);
1167 // First time use. Allocate a cache in C heap
1168 if (_oop_map_cache == NULL) {
1169 // Release stores from OopMapCache constructor before assignment
1170 // to _oop_map_cache. C++ compilers on ppc do not emit the
1171 // required memory barrier only because of the volatile
1172 // qualifier of _oop_map_cache.
1173 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1174 }
1175 }
1176 // _oop_map_cache is constant after init; lookup below does is own locking.
1177 _oop_map_cache->lookup(method, bci, entry_for);
1178 }
1179
1180
1181 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1182 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1183 Symbol* f_name = fs.name();
1184 Symbol* f_sig = fs.signature();
1185 if (f_name == name && f_sig == sig) {
1186 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1187 return true;
1188 }
1189 }
1190 return false;
1191 }
1192
1193
1194 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1195 const int n = local_interfaces()->length();
1196 for (int i = 0; i < n; i++) {
1197 Klass* intf1 = local_interfaces()->at(i);
1198 assert(intf1->is_interface(), "just checking type");
1199 // search for field in current interface
1200 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1201 assert(fd->is_static(), "interface field must be static");
1202 return intf1;
1203 }
1204 // search for field in direct superinterfaces
1205 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1206 if (intf2 != NULL) return intf2;
1207 }
1208 // otherwise field lookup fails
1209 return NULL;
1210 }
1211
1212
1213 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1214 // search order according to newest JVM spec (5.4.3.2, p.167).
1215 // 1) search for field in current klass
1216 if (find_local_field(name, sig, fd)) {
1217 return const_cast<InstanceKlass*>(this);
1218 }
1219 // 2) search for field recursively in direct superinterfaces
1220 { Klass* intf = find_interface_field(name, sig, fd);
1221 if (intf != NULL) return intf;
1222 }
1223 // 3) apply field lookup recursively if superclass exists
1224 { Klass* supr = super();
1225 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1226 }
1227 // 4) otherwise field lookup fails
1228 return NULL;
1229 }
1230
1231
1232 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1233 // search order according to newest JVM spec (5.4.3.2, p.167).
1234 // 1) search for field in current klass
1235 if (find_local_field(name, sig, fd)) {
1236 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1237 }
1238 // 2) search for field recursively in direct superinterfaces
1239 if (is_static) {
1240 Klass* intf = find_interface_field(name, sig, fd);
1241 if (intf != NULL) return intf;
1242 }
1243 // 3) apply field lookup recursively if superclass exists
1244 { Klass* supr = super();
1245 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1246 }
1247 // 4) otherwise field lookup fails
1248 return NULL;
1249 }
1250
1251
1252 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1253 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1254 if (fs.offset() == offset) {
1255 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1256 if (fd->is_static() == is_static) return true;
1257 }
1258 }
1259 return false;
1260 }
1261
1262
1263 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1264 Klass* klass = const_cast<InstanceKlass*>(this);
1265 while (klass != NULL) {
1266 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1267 return true;
1268 }
1269 klass = klass->super();
1270 }
1271 return false;
1272 }
1273
1274
1275 void InstanceKlass::methods_do(void f(Method* method)) {
1276 // Methods aren't stable until they are loaded. This can be read outside
1277 // a lock through the ClassLoaderData for profiling
1278 if (!is_loaded()) {
1279 return;
1280 }
1281
1282 int len = methods()->length();
1283 for (int index = 0; index < len; index++) {
1284 Method* m = methods()->at(index);
1285 assert(m->is_method(), "must be method");
1286 f(m);
1287 }
1288 }
1289
1290
1291 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1292 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1293 if (fs.access_flags().is_static()) {
1294 fieldDescriptor& fd = fs.field_descriptor();
1295 cl->do_field(&fd);
1296 }
1297 }
1298 }
1299
1300
1301 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1302 instanceKlassHandle h_this(THREAD, this);
1303 do_local_static_fields_impl(h_this, f, mirror, CHECK);
1304 }
1305
1306
1307 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1308 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1309 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1310 if (fs.access_flags().is_static()) {
1311 fieldDescriptor& fd = fs.field_descriptor();
1312 f(&fd, mirror, CHECK);
1313 }
1314 }
1315 }
1316
1317
1318 static int compare_fields_by_offset(int* a, int* b) {
1319 return a[0] - b[0];
1320 }
1321
1322 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1323 InstanceKlass* super = superklass();
1324 if (super != NULL) {
1325 super->do_nonstatic_fields(cl);
1326 }
1327 fieldDescriptor fd;
1328 int length = java_fields_count();
1329 // In DebugInfo nonstatic fields are sorted by offset.
1330 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1331 int j = 0;
1332 for (int i = 0; i < length; i += 1) {
1333 fd.reinitialize(this, i);
1334 if (!fd.is_static()) {
1335 fields_sorted[j + 0] = fd.offset();
1336 fields_sorted[j + 1] = i;
1337 j += 2;
1338 }
1339 }
1340 if (j > 0) {
1341 length = j;
1342 // _sort_Fn is defined in growableArray.hpp.
1343 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1344 for (int i = 0; i < length; i += 2) {
1345 fd.reinitialize(this, fields_sorted[i + 1]);
1346 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1347 cl->do_field(&fd);
1348 }
1349 }
1350 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1351 }
1352
1353
1354 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1355 if (array_klasses() != NULL)
1356 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1357 }
1358
1359 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1360 if (array_klasses() != NULL)
1361 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1362 }
1363
1364 #ifdef ASSERT
1365 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1366 int len = methods->length();
1367 for (int index = 0; index < len; index++) {
1368 Method* m = methods->at(index);
1369 assert(m->is_method(), "must be method");
1370 if (m->signature() == signature && m->name() == name) {
1371 return index;
1372 }
1373 }
1374 return -1;
1375 }
1376 #endif
1377
1378 static int binary_search(Array<Method*>* methods, Symbol* name) {
1379 int len = methods->length();
1380 // methods are sorted, so do binary search
1381 int l = 0;
1382 int h = len - 1;
1383 while (l <= h) {
1384 int mid = (l + h) >> 1;
1385 Method* m = methods->at(mid);
1386 assert(m->is_method(), "must be method");
1387 int res = m->name()->fast_compare(name);
1388 if (res == 0) {
1389 return mid;
1390 } else if (res < 0) {
1391 l = mid + 1;
1392 } else {
1393 h = mid - 1;
1394 }
1395 }
1396 return -1;
1397 }
1398
1399 // find_method looks up the name/signature in the local methods array
1400 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1401 return find_method_impl(name, signature, false);
1402 }
1403
1404 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const {
1405 return InstanceKlass::find_method_impl(methods(), name, signature, skipping_overpass);
1406 }
1407
1408 // find_instance_method looks up the name/signature in the local methods array
1409 // and skips over static methods
1410 Method* InstanceKlass::find_instance_method(
1411 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1412 Method* meth = InstanceKlass::find_method(methods, name, signature);
1413 if (meth != NULL && meth->is_static()) {
1414 meth = NULL;
1415 }
1416 return meth;
1417 }
1418
1419 // find_method looks up the name/signature in the local methods array
1420 Method* InstanceKlass::find_method(
1421 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1422 return InstanceKlass::find_method_impl(methods, name, signature, false);
1423 }
1424
1425 Method* InstanceKlass::find_method_impl(
1426 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1427 int hit = find_method_index(methods, name, signature, skipping_overpass);
1428 return hit >= 0 ? methods->at(hit): NULL;
1429 }
1430
1431 // Used directly for default_methods to find the index into the
1432 // default_vtable_indices, and indirectly by find_method
1433 // find_method_index looks in the local methods array to return the index
1434 // of the matching name/signature. If, overpass methods are being ignored,
1435 // the search continues to find a potential non-overpass match. This capability
1436 // is important during method resolution to prefer a static method, for example,
1437 // over an overpass method.
1438 int InstanceKlass::find_method_index(
1439 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1440 int hit = binary_search(methods, name);
1441 if (hit != -1) {
1442 Method* m = methods->at(hit);
1443 // Do linear search to find matching signature. First, quick check
1444 // for common case, ignoring overpasses if requested.
1445 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return hit;
1446
1447 // search downwards through overloaded methods
1448 int i;
1449 for (i = hit - 1; i >= 0; --i) {
1450 Method* m = methods->at(i);
1451 assert(m->is_method(), "must be method");
1452 if (m->name() != name) break;
1453 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1454 }
1455 // search upwards
1456 for (i = hit + 1; i < methods->length(); ++i) {
1457 Method* m = methods->at(i);
1458 assert(m->is_method(), "must be method");
1459 if (m->name() != name) break;
1460 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1461 }
1462 // not found
1463 #ifdef ASSERT
1464 int index = skipping_overpass ? -1 : linear_search(methods, name, signature);
1465 assert(index == -1, err_msg("binary search should have found entry %d", index));
1466 #endif
1467 }
1468 return -1;
1469 }
1470 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1471 return find_method_by_name(methods(), name, end);
1472 }
1473
1474 int InstanceKlass::find_method_by_name(
1475 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1476 assert(end_ptr != NULL, "just checking");
1477 int start = binary_search(methods, name);
1478 int end = start + 1;
1479 if (start != -1) {
1480 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1481 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1482 *end_ptr = end;
1483 return start;
1484 }
1485 return -1;
1486 }
1487
1488 // uncached_lookup_method searches both the local class methods array and all
1489 // superclasses methods arrays, skipping any overpass methods in superclasses.
1490 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const {
1491 MethodLookupMode lookup_mode = mode;
1492 Klass* klass = const_cast<InstanceKlass*>(this);
1493 while (klass != NULL) {
1494 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, (lookup_mode == skip_overpass));
1495 if (method != NULL) {
1496 return method;
1497 }
1498 klass = InstanceKlass::cast(klass)->super();
1499 lookup_mode = skip_overpass; // Always ignore overpass methods in superclasses
1500 }
1501 return NULL;
1502 }
1503
1504 #ifdef ASSERT
1505 // search through class hierarchy and return true if this class or
1506 // one of the superclasses was redefined
1507 bool InstanceKlass::has_redefined_this_or_super() const {
1508 const InstanceKlass* klass = this;
1509 while (klass != NULL) {
1510 if (klass->has_been_redefined()) {
1511 return true;
1512 }
1513 klass = InstanceKlass::cast(klass->super());
1514 }
1515 return false;
1516 }
1517 #endif
1518
1519 // lookup a method in the default methods list then in all transitive interfaces
1520 // Do NOT return private or static methods
1521 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1522 Symbol* signature) const {
1523 Method* m = NULL;
1524 if (default_methods() != NULL) {
1525 m = find_method(default_methods(), name, signature);
1526 }
1527 // Look up interfaces
1528 if (m == NULL) {
1529 m = lookup_method_in_all_interfaces(name, signature, normal);
1530 }
1531 return m;
1532 }
1533
1534 // lookup a method in all the interfaces that this class implements
1535 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1536 // They should only be found in the initial InterfaceMethodRef
1537 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1538 Symbol* signature,
1539 MethodLookupMode mode) const {
1540 Array<Klass*>* all_ifs = transitive_interfaces();
1541 int num_ifs = all_ifs->length();
1542 InstanceKlass *ik = NULL;
1543 for (int i = 0; i < num_ifs; i++) {
1544 ik = InstanceKlass::cast(all_ifs->at(i));
1545 Method* m = ik->lookup_method(name, signature);
1546 if (m != NULL && m->is_public() && !m->is_static() &&
1547 ((mode != skip_defaults) || !m->is_default_method())) {
1548 return m;
1549 }
1550 }
1551 return NULL;
1552 }
1553
1554 /* jni_id_for_impl for jfieldIds only */
1555 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1556 MutexLocker ml(JfieldIdCreation_lock);
1557 // Retry lookup after we got the lock
1558 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1559 if (probe == NULL) {
1560 // Slow case, allocate new static field identifier
1561 probe = new JNIid(this_k(), offset, this_k->jni_ids());
1562 this_k->set_jni_ids(probe);
1563 }
1564 return probe;
1565 }
1566
1567
1568 /* jni_id_for for jfieldIds only */
1569 JNIid* InstanceKlass::jni_id_for(int offset) {
1570 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1571 if (probe == NULL) {
1572 probe = jni_id_for_impl(this, offset);
1573 }
1574 return probe;
1575 }
1576
1577 u2 InstanceKlass::enclosing_method_data(int offset) {
1578 Array<jushort>* inner_class_list = inner_classes();
1579 if (inner_class_list == NULL) {
1580 return 0;
1581 }
1582 int length = inner_class_list->length();
1583 if (length % inner_class_next_offset == 0) {
1584 return 0;
1585 } else {
1586 int index = length - enclosing_method_attribute_size;
1587 assert(offset < enclosing_method_attribute_size, "invalid offset");
1588 return inner_class_list->at(index + offset);
1589 }
1590 }
1591
1592 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1593 u2 method_index) {
1594 Array<jushort>* inner_class_list = inner_classes();
1595 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1596 int length = inner_class_list->length();
1597 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1598 int index = length - enclosing_method_attribute_size;
1599 inner_class_list->at_put(
1600 index + enclosing_method_class_index_offset, class_index);
1601 inner_class_list->at_put(
1602 index + enclosing_method_method_index_offset, method_index);
1603 }
1604 }
1605
1606 // Lookup or create a jmethodID.
1607 // This code is called by the VMThread and JavaThreads so the
1608 // locking has to be done very carefully to avoid deadlocks
1609 // and/or other cache consistency problems.
1610 //
1611 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1612 size_t idnum = (size_t)method_h->method_idnum();
1613 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1614 size_t length = 0;
1615 jmethodID id = NULL;
1616
1617 // We use a double-check locking idiom here because this cache is
1618 // performance sensitive. In the normal system, this cache only
1619 // transitions from NULL to non-NULL which is safe because we use
1620 // release_set_methods_jmethod_ids() to advertise the new cache.
1621 // A partially constructed cache should never be seen by a racing
1622 // thread. We also use release_store_ptr() to save a new jmethodID
1623 // in the cache so a partially constructed jmethodID should never be
1624 // seen either. Cache reads of existing jmethodIDs proceed without a
1625 // lock, but cache writes of a new jmethodID requires uniqueness and
1626 // creation of the cache itself requires no leaks so a lock is
1627 // generally acquired in those two cases.
1628 //
1629 // If the RedefineClasses() API has been used, then this cache can
1630 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1631 // Cache creation requires no leaks and we require safety between all
1632 // cache accesses and freeing of the old cache so a lock is generally
1633 // acquired when the RedefineClasses() API has been used.
1634
1635 if (jmeths != NULL) {
1636 // the cache already exists
1637 if (!ik_h->idnum_can_increment()) {
1638 // the cache can't grow so we can just get the current values
1639 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1640 } else {
1641 // cache can grow so we have to be more careful
1642 if (Threads::number_of_threads() == 0 ||
1643 SafepointSynchronize::is_at_safepoint()) {
1644 // we're single threaded or at a safepoint - no locking needed
1645 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1646 } else {
1647 MutexLocker ml(JmethodIdCreation_lock);
1648 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1649 }
1650 }
1651 }
1652 // implied else:
1653 // we need to allocate a cache so default length and id values are good
1654
1655 if (jmeths == NULL || // no cache yet
1656 length <= idnum || // cache is too short
1657 id == NULL) { // cache doesn't contain entry
1658
1659 // This function can be called by the VMThread so we have to do all
1660 // things that might block on a safepoint before grabbing the lock.
1661 // Otherwise, we can deadlock with the VMThread or have a cache
1662 // consistency issue. These vars keep track of what we might have
1663 // to free after the lock is dropped.
1664 jmethodID to_dealloc_id = NULL;
1665 jmethodID* to_dealloc_jmeths = NULL;
1666
1667 // may not allocate new_jmeths or use it if we allocate it
1668 jmethodID* new_jmeths = NULL;
1669 if (length <= idnum) {
1670 // allocate a new cache that might be used
1671 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1672 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1673 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1674 // cache size is stored in element[0], other elements offset by one
1675 new_jmeths[0] = (jmethodID)size;
1676 }
1677
1678 // allocate a new jmethodID that might be used
1679 jmethodID new_id = NULL;
1680 if (method_h->is_old() && !method_h->is_obsolete()) {
1681 // The method passed in is old (but not obsolete), we need to use the current version
1682 Method* current_method = ik_h->method_with_idnum((int)idnum);
1683 assert(current_method != NULL, "old and but not obsolete, so should exist");
1684 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1685 } else {
1686 // It is the current version of the method or an obsolete method,
1687 // use the version passed in
1688 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1689 }
1690
1691 if (Threads::number_of_threads() == 0 ||
1692 SafepointSynchronize::is_at_safepoint()) {
1693 // we're single threaded or at a safepoint - no locking needed
1694 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1695 &to_dealloc_id, &to_dealloc_jmeths);
1696 } else {
1697 MutexLocker ml(JmethodIdCreation_lock);
1698 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1699 &to_dealloc_id, &to_dealloc_jmeths);
1700 }
1701
1702 // The lock has been dropped so we can free resources.
1703 // Free up either the old cache or the new cache if we allocated one.
1704 if (to_dealloc_jmeths != NULL) {
1705 FreeHeap(to_dealloc_jmeths);
1706 }
1707 // free up the new ID since it wasn't needed
1708 if (to_dealloc_id != NULL) {
1709 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1710 }
1711 }
1712 return id;
1713 }
1714
1715
1716 // Common code to fetch the jmethodID from the cache or update the
1717 // cache with the new jmethodID. This function should never do anything
1718 // that causes the caller to go to a safepoint or we can deadlock with
1719 // the VMThread or have cache consistency issues.
1720 //
1721 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1722 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1723 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1724 jmethodID** to_dealloc_jmeths_p) {
1725 assert(new_id != NULL, "sanity check");
1726 assert(to_dealloc_id_p != NULL, "sanity check");
1727 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1728 assert(Threads::number_of_threads() == 0 ||
1729 SafepointSynchronize::is_at_safepoint() ||
1730 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1731
1732 // reacquire the cache - we are locked, single threaded or at a safepoint
1733 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1734 jmethodID id = NULL;
1735 size_t length = 0;
1736
1737 if (jmeths == NULL || // no cache yet
1738 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1739 if (jmeths != NULL) {
1740 // copy any existing entries from the old cache
1741 for (size_t index = 0; index < length; index++) {
1742 new_jmeths[index+1] = jmeths[index+1];
1743 }
1744 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1745 }
1746 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1747 } else {
1748 // fetch jmethodID (if any) from the existing cache
1749 id = jmeths[idnum+1];
1750 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1751 }
1752 if (id == NULL) {
1753 // No matching jmethodID in the existing cache or we have a new
1754 // cache or we just grew the cache. This cache write is done here
1755 // by the first thread to win the foot race because a jmethodID
1756 // needs to be unique once it is generally available.
1757 id = new_id;
1758
1759 // The jmethodID cache can be read while unlocked so we have to
1760 // make sure the new jmethodID is complete before installing it
1761 // in the cache.
1762 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1763 } else {
1764 *to_dealloc_id_p = new_id; // save new id for later delete
1765 }
1766 return id;
1767 }
1768
1769
1770 // Common code to get the jmethodID cache length and the jmethodID
1771 // value at index idnum if there is one.
1772 //
1773 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1774 size_t idnum, size_t *length_p, jmethodID* id_p) {
1775 assert(cache != NULL, "sanity check");
1776 assert(length_p != NULL, "sanity check");
1777 assert(id_p != NULL, "sanity check");
1778
1779 // cache size is stored in element[0], other elements offset by one
1780 *length_p = (size_t)cache[0];
1781 if (*length_p <= idnum) { // cache is too short
1782 *id_p = NULL;
1783 } else {
1784 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1785 }
1786 }
1787
1788
1789 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1790 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1791 size_t idnum = (size_t)method->method_idnum();
1792 jmethodID* jmeths = methods_jmethod_ids_acquire();
1793 size_t length; // length assigned as debugging crumb
1794 jmethodID id = NULL;
1795 if (jmeths != NULL && // If there is a cache
1796 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1797 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1798 }
1799 return id;
1800 }
1801
1802
1803 //
1804 // Walk the list of dependent nmethods searching for nmethods which
1805 // are dependent on the changes that were passed in and mark them for
1806 // deoptimization. Returns the number of nmethods found.
1807 //
1808 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1809 assert_locked_or_safepoint(CodeCache_lock);
1810 int found = 0;
1811 nmethodBucket* b = _dependencies;
1812 while (b != NULL) {
1813 nmethod* nm = b->get_nmethod();
1814 // since dependencies aren't removed until an nmethod becomes a zombie,
1815 // the dependency list may contain nmethods which aren't alive.
1816 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1817 if (TraceDependencies) {
1818 ResourceMark rm;
1819 tty->print_cr("Marked for deoptimization");
1820 tty->print_cr(" context = %s", this->external_name());
1821 changes.print();
1822 nm->print();
1823 nm->print_dependencies();
1824 }
1825 nm->mark_for_deoptimization();
1826 found++;
1827 }
1828 b = b->next();
1829 }
1830 return found;
1831 }
1832
1833
1834 //
1835 // Add an nmethodBucket to the list of dependencies for this nmethod.
1836 // It's possible that an nmethod has multiple dependencies on this klass
1837 // so a count is kept for each bucket to guarantee that creation and
1838 // deletion of dependencies is consistent.
1839 //
1840 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1841 assert_locked_or_safepoint(CodeCache_lock);
1842 nmethodBucket* b = _dependencies;
1843 nmethodBucket* last = NULL;
1844 while (b != NULL) {
1845 if (nm == b->get_nmethod()) {
1846 b->increment();
1847 return;
1848 }
1849 b = b->next();
1850 }
1851 _dependencies = new nmethodBucket(nm, _dependencies);
1852 }
1853
1854
1855 //
1856 // Decrement count of the nmethod in the dependency list and remove
1857 // the bucket competely when the count goes to 0. This method must
1858 // find a corresponding bucket otherwise there's a bug in the
1859 // recording of dependecies.
1860 //
1861 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1862 assert_locked_or_safepoint(CodeCache_lock);
1863 nmethodBucket* b = _dependencies;
1864 nmethodBucket* last = NULL;
1865 while (b != NULL) {
1866 if (nm == b->get_nmethod()) {
1867 if (b->decrement() == 0) {
1868 if (last == NULL) {
1869 _dependencies = b->next();
1870 } else {
1871 last->set_next(b->next());
1872 }
1873 delete b;
1874 }
1875 return;
1876 }
1877 last = b;
1878 b = b->next();
1879 }
1880 #ifdef ASSERT
1881 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1882 nm->print();
1883 #endif // ASSERT
1884 ShouldNotReachHere();
1885 }
1886
1887
1888 #ifndef PRODUCT
1889 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1890 nmethodBucket* b = _dependencies;
1891 int idx = 0;
1892 while (b != NULL) {
1893 nmethod* nm = b->get_nmethod();
1894 tty->print("[%d] count=%d { ", idx++, b->count());
1895 if (!verbose) {
1896 nm->print_on(tty, "nmethod");
1897 tty->print_cr(" } ");
1898 } else {
1899 nm->print();
1900 nm->print_dependencies();
1901 tty->print_cr("--- } ");
1902 }
1903 b = b->next();
1904 }
1905 }
1906
1907
1908 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1909 nmethodBucket* b = _dependencies;
1910 while (b != NULL) {
1911 if (nm == b->get_nmethod()) {
1912 return true;
1913 }
1914 b = b->next();
1915 }
1916 return false;
1917 }
1918 #endif //PRODUCT
1919
1920
1921 // Garbage collection
1922
1923 #ifdef ASSERT
1924 template <class T> void assert_is_in(T *p) {
1925 T heap_oop = oopDesc::load_heap_oop(p);
1926 if (!oopDesc::is_null(heap_oop)) {
1927 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1928 assert(Universe::heap()->is_in(o), "should be in heap");
1929 }
1930 }
1931 template <class T> void assert_is_in_closed_subset(T *p) {
1932 T heap_oop = oopDesc::load_heap_oop(p);
1933 if (!oopDesc::is_null(heap_oop)) {
1934 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1935 assert(Universe::heap()->is_in_closed_subset(o),
1936 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
1937 }
1938 }
1939 template <class T> void assert_is_in_reserved(T *p) {
1940 T heap_oop = oopDesc::load_heap_oop(p);
1941 if (!oopDesc::is_null(heap_oop)) {
1942 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1943 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1944 }
1945 }
1946 template <class T> void assert_nothing(T *p) {}
1947
1948 #else
1949 template <class T> void assert_is_in(T *p) {}
1950 template <class T> void assert_is_in_closed_subset(T *p) {}
1951 template <class T> void assert_is_in_reserved(T *p) {}
1952 template <class T> void assert_nothing(T *p) {}
1953 #endif // ASSERT
1954
1955 //
1956 // Macros that iterate over areas of oops which are specialized on type of
1957 // oop pointer either narrow or wide, depending on UseCompressedOops
1958 //
1959 // Parameters are:
1960 // T - type of oop to point to (either oop or narrowOop)
1961 // start_p - starting pointer for region to iterate over
1962 // count - number of oops or narrowOops to iterate over
1963 // do_oop - action to perform on each oop (it's arbitrary C code which
1964 // makes it more efficient to put in a macro rather than making
1965 // it a template function)
1966 // assert_fn - assert function which is template function because performance
1967 // doesn't matter when enabled.
1968 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1969 T, start_p, count, do_oop, \
1970 assert_fn) \
1971 { \
1972 T* p = (T*)(start_p); \
1973 T* const end = p + (count); \
1974 while (p < end) { \
1975 (assert_fn)(p); \
1976 do_oop; \
1977 ++p; \
1978 } \
1979 }
1980
1981 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1982 T, start_p, count, do_oop, \
1983 assert_fn) \
1984 { \
1985 T* const start = (T*)(start_p); \
1986 T* p = start + (count); \
1987 while (start < p) { \
1988 --p; \
1989 (assert_fn)(p); \
1990 do_oop; \
1991 } \
1992 }
1993
1994 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
1995 T, start_p, count, low, high, \
1996 do_oop, assert_fn) \
1997 { \
1998 T* const l = (T*)(low); \
1999 T* const h = (T*)(high); \
2000 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
2001 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
2002 "bounded region must be properly aligned"); \
2003 T* p = (T*)(start_p); \
2004 T* end = p + (count); \
2005 if (p < l) p = l; \
2006 if (end > h) end = h; \
2007 while (p < end) { \
2008 (assert_fn)(p); \
2009 do_oop; \
2010 ++p; \
2011 } \
2012 }
2013
2014
2015 // The following macros call specialized macros, passing either oop or
2016 // narrowOop as the specialization type. These test the UseCompressedOops
2017 // flag.
2018 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
2019 { \
2020 /* Compute oopmap block range. The common case \
2021 is nonstatic_oop_map_size == 1. */ \
2022 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2023 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2024 if (UseCompressedOops) { \
2025 while (map < end_map) { \
2026 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
2027 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2028 do_oop, assert_fn) \
2029 ++map; \
2030 } \
2031 } else { \
2032 while (map < end_map) { \
2033 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
2034 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2035 do_oop, assert_fn) \
2036 ++map; \
2037 } \
2038 } \
2039 }
2040
2041 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
2042 { \
2043 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
2044 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
2045 if (UseCompressedOops) { \
2046 while (start_map < map) { \
2047 --map; \
2048 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
2049 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2050 do_oop, assert_fn) \
2051 } \
2052 } else { \
2053 while (start_map < map) { \
2054 --map; \
2055 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
2056 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2057 do_oop, assert_fn) \
2058 } \
2059 } \
2060 }
2061
2062 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
2063 assert_fn) \
2064 { \
2065 /* Compute oopmap block range. The common case is \
2066 nonstatic_oop_map_size == 1, so we accept the \
2067 usually non-existent extra overhead of examining \
2068 all the maps. */ \
2069 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2070 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2071 if (UseCompressedOops) { \
2072 while (map < end_map) { \
2073 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
2074 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2075 low, high, \
2076 do_oop, assert_fn) \
2077 ++map; \
2078 } \
2079 } else { \
2080 while (map < end_map) { \
2081 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2082 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2083 low, high, \
2084 do_oop, assert_fn) \
2085 ++map; \
2086 } \
2087 } \
2088 }
2089
2090 void InstanceKlass::oop_follow_contents(oop obj) {
2091 assert(obj != NULL, "can't follow the content of NULL object");
2092 MarkSweep::follow_klass(obj->klass());
2093 InstanceKlass_OOP_MAP_ITERATE( \
2094 obj, \
2095 MarkSweep::mark_and_push(p), \
2096 assert_is_in_closed_subset)
2097 }
2098
2099 #if INCLUDE_ALL_GCS
2100 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2101 oop obj) {
2102 assert(obj != NULL, "can't follow the content of NULL object");
2103 PSParallelCompact::follow_klass(cm, obj->klass());
2104 // Only mark the header and let the scan of the meta-data mark
2105 // everything else.
2106 InstanceKlass_OOP_MAP_ITERATE( \
2107 obj, \
2108 PSParallelCompact::mark_and_push(cm, p), \
2109 assert_is_in)
2110 }
2111 #endif // INCLUDE_ALL_GCS
2112
2113 // closure's do_metadata() method dictates whether the given closure should be
2114 // applied to the klass ptr in the object header.
2115
2116 #define if_do_metadata_checked(closure, nv_suffix) \
2117 /* Make sure the non-virtual and the virtual versions match. */ \
2118 assert(closure->do_metadata##nv_suffix() == closure->do_metadata(), \
2119 "Inconsistency in do_metadata"); \
2120 if (closure->do_metadata##nv_suffix())
2121
2122 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2123 \
2124 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2125 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2126 /* header */ \
2127 if_do_metadata_checked(closure, nv_suffix) { \
2128 closure->do_klass##nv_suffix(obj->klass()); \
2129 } \
2130 InstanceKlass_OOP_MAP_ITERATE( \
2131 obj, \
2132 SpecializationStats:: \
2133 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2134 (closure)->do_oop##nv_suffix(p), \
2135 assert_is_in_closed_subset) \
2136 return size_helper(); \
2137 }
2138
2139 #if INCLUDE_ALL_GCS
2140 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2141 \
2142 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2143 OopClosureType* closure) { \
2144 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2145 /* header */ \
2146 if_do_metadata_checked(closure, nv_suffix) { \
2147 closure->do_klass##nv_suffix(obj->klass()); \
2148 } \
2149 /* instance variables */ \
2150 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2151 obj, \
2152 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2153 (closure)->do_oop##nv_suffix(p), \
2154 assert_is_in_closed_subset) \
2155 return size_helper(); \
2156 }
2157 #endif // INCLUDE_ALL_GCS
2158
2159 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2160 \
2161 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2162 OopClosureType* closure, \
2163 MemRegion mr) { \
2164 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2165 if_do_metadata_checked(closure, nv_suffix) { \
2166 if (mr.contains(obj)) { \
2167 closure->do_klass##nv_suffix(obj->klass()); \
2168 } \
2169 } \
2170 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2171 obj, mr.start(), mr.end(), \
2172 (closure)->do_oop##nv_suffix(p), \
2173 assert_is_in_closed_subset) \
2174 return size_helper(); \
2175 }
2176
2177 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2178 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2179 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2180 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2181 #if INCLUDE_ALL_GCS
2182 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2183 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2184 #endif // INCLUDE_ALL_GCS
2185
2186 int InstanceKlass::oop_adjust_pointers(oop obj) {
2187 int size = size_helper();
2188 InstanceKlass_OOP_MAP_ITERATE( \
2189 obj, \
2190 MarkSweep::adjust_pointer(p), \
2191 assert_is_in)
2192 return size;
2193 }
2194
2195 #if INCLUDE_ALL_GCS
2196 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2197 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2198 obj, \
2199 if (PSScavenge::should_scavenge(p)) { \
2200 pm->claim_or_forward_depth(p); \
2201 }, \
2202 assert_nothing )
2203 }
2204
2205 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2206 int size = size_helper();
2207 InstanceKlass_OOP_MAP_ITERATE( \
2208 obj, \
2209 PSParallelCompact::adjust_pointer(p), \
2210 assert_is_in)
2211 return size;
2212 }
2213
2214 #endif // INCLUDE_ALL_GCS
2215
2216 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2217 assert(is_loader_alive(is_alive), "this klass should be live");
2218 if (is_interface()) {
2219 if (ClassUnloading) {
2220 Klass* impl = implementor();
2221 if (impl != NULL) {
2222 if (!impl->is_loader_alive(is_alive)) {
2223 // remove this guy
2224 Klass** klass = adr_implementor();
2225 assert(klass != NULL, "null klass");
2226 if (klass != NULL) {
2227 *klass = NULL;
2228 }
2229 }
2230 }
2231 }
2232 }
2233 }
2234
2235 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2236 for (int m = 0; m < methods()->length(); m++) {
2237 MethodData* mdo = methods()->at(m)->method_data();
2238 if (mdo != NULL) {
2239 mdo->clean_method_data(is_alive);
2240 }
2241 }
2242 }
2243
2244
2245 static void remove_unshareable_in_class(Klass* k) {
2246 // remove klass's unshareable info
2247 k->remove_unshareable_info();
2248 }
2249
2250 void InstanceKlass::remove_unshareable_info() {
2251 Klass::remove_unshareable_info();
2252 // Unlink the class
2253 if (is_linked()) {
2254 unlink_class();
2255 }
2256 init_implementor();
2257
2258 constants()->remove_unshareable_info();
2259
2260 for (int i = 0; i < methods()->length(); i++) {
2261 Method* m = methods()->at(i);
2262 m->remove_unshareable_info();
2263 }
2264
2265 // do array classes also.
2266 array_klasses_do(remove_unshareable_in_class);
2267 }
2268
2269 void restore_unshareable_in_class(Klass* k, TRAPS) {
2270 k->restore_unshareable_info(CHECK);
2271 }
2272
2273 void InstanceKlass::restore_unshareable_info(TRAPS) {
2274 Klass::restore_unshareable_info(CHECK);
2275 instanceKlassHandle ik(THREAD, this);
2276
2277 Array<Method*>* methods = ik->methods();
2278 int num_methods = methods->length();
2279 for (int index2 = 0; index2 < num_methods; ++index2) {
2280 methodHandle m(THREAD, methods->at(index2));
2281 m->restore_unshareable_info(CHECK);
2282 }
2283 if (JvmtiExport::has_redefined_a_class()) {
2284 // Reinitialize vtable because RedefineClasses may have changed some
2285 // entries in this vtable for super classes so the CDS vtable might
2286 // point to old or obsolete entries. RedefineClasses doesn't fix up
2287 // vtables in the shared system dictionary, only the main one.
2288 // It also redefines the itable too so fix that too.
2289 ResourceMark rm(THREAD);
2290 ik->vtable()->initialize_vtable(false, CHECK);
2291 ik->itable()->initialize_itable(false, CHECK);
2292 }
2293
2294 // restore constant pool resolved references
2295 ik->constants()->restore_unshareable_info(CHECK);
2296
2297 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2298 }
2299
2300 static void clear_all_breakpoints(Method* m) {
2301 m->clear_all_breakpoints();
2302 }
2303
2304
2305 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2306 // notify the debugger
2307 if (JvmtiExport::should_post_class_unload()) {
2308 JvmtiExport::post_class_unload(ik);
2309 }
2310
2311 // notify ClassLoadingService of class unload
2312 ClassLoadingService::notify_class_unloaded(ik);
2313 }
2314
2315 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2316 // Clean up C heap
2317 ik->release_C_heap_structures();
2318 ik->constants()->release_C_heap_structures();
2319 }
2320
2321 void InstanceKlass::release_C_heap_structures() {
2322
2323 // Can't release the constant pool here because the constant pool can be
2324 // deallocated separately from the InstanceKlass for default methods and
2325 // redefine classes.
2326
2327 // Deallocate oop map cache
2328 if (_oop_map_cache != NULL) {
2329 delete _oop_map_cache;
2330 _oop_map_cache = NULL;
2331 }
2332
2333 // Deallocate JNI identifiers for jfieldIDs
2334 JNIid::deallocate(jni_ids());
2335 set_jni_ids(NULL);
2336
2337 jmethodID* jmeths = methods_jmethod_ids_acquire();
2338 if (jmeths != (jmethodID*)NULL) {
2339 release_set_methods_jmethod_ids(NULL);
2340 FreeHeap(jmeths);
2341 }
2342
2343 // Deallocate MemberNameTable
2344 {
2345 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2346 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2347 MemberNameTable* mnt = member_names();
2348 if (mnt != NULL) {
2349 delete mnt;
2350 set_member_names(NULL);
2351 }
2352 }
2353
2354 // release dependencies
2355 nmethodBucket* b = _dependencies;
2356 _dependencies = NULL;
2357 while (b != NULL) {
2358 nmethodBucket* next = b->next();
2359 delete b;
2360 b = next;
2361 }
2362
2363 // Deallocate breakpoint records
2364 if (breakpoints() != 0x0) {
2365 methods_do(clear_all_breakpoints);
2366 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2367 }
2368
2369 // deallocate information about previous versions
2370 if (_previous_versions != NULL) {
2371 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2372 PreviousVersionNode * pv_node = _previous_versions->at(i);
2373 delete pv_node;
2374 }
2375 delete _previous_versions;
2376 _previous_versions = NULL;
2377 }
2378
2379 // deallocate the cached class file
2380 if (_cached_class_file != NULL) {
2381 os::free(_cached_class_file, mtClass);
2382 _cached_class_file = NULL;
2383 }
2384
2385 // Decrement symbol reference counts associated with the unloaded class.
2386 if (_name != NULL) _name->decrement_refcount();
2387 // unreference array name derived from this class name (arrays of an unloaded
2388 // class can't be referenced anymore).
2389 if (_array_name != NULL) _array_name->decrement_refcount();
2390 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2391
2392 assert(_total_instanceKlass_count >= 1, "Sanity check");
2393 Atomic::dec(&_total_instanceKlass_count);
2394 }
2395
2396 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2397 if (array == NULL) {
2398 _source_debug_extension = NULL;
2399 } else {
2400 // Adding one to the attribute length in order to store a null terminator
2401 // character could cause an overflow because the attribute length is
2402 // already coded with an u4 in the classfile, but in practice, it's
2403 // unlikely to happen.
2404 assert((length+1) > length, "Overflow checking");
2405 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2406 for (int i = 0; i < length; i++) {
2407 sde[i] = array[i];
2408 }
2409 sde[length] = '\0';
2410 _source_debug_extension = sde;
2411 }
2412 }
2413
2414 address InstanceKlass::static_field_addr(int offset) {
2415 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2416 }
2417
2418
2419 const char* InstanceKlass::signature_name() const {
2420 int hash_len = 0;
2421 char hash_buf[40];
2422
2423 // If this is an anonymous class, append a hash to make the name unique
2424 if (is_anonymous()) {
2425 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2426 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
2427 hash_len = (int)strlen(hash_buf);
2428 }
2429
2430 // Get the internal name as a c string
2431 const char* src = (const char*) (name()->as_C_string());
2432 const int src_length = (int)strlen(src);
2433
2434 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2435
2436 // Add L as type indicator
2437 int dest_index = 0;
2438 dest[dest_index++] = 'L';
2439
2440 // Add the actual class name
2441 for (int src_index = 0; src_index < src_length; ) {
2442 dest[dest_index++] = src[src_index++];
2443 }
2444
2445 // If we have a hash, append it
2446 for (int hash_index = 0; hash_index < hash_len; ) {
2447 dest[dest_index++] = hash_buf[hash_index++];
2448 }
2449
2450 // Add the semicolon and the NULL
2451 dest[dest_index++] = ';';
2452 dest[dest_index] = '\0';
2453 return dest;
2454 }
2455
2456 // different verisons of is_same_class_package
2457 bool InstanceKlass::is_same_class_package(Klass* class2) {
2458 Klass* class1 = this;
2459 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2460 Symbol* classname1 = class1->name();
2461
2462 if (class2->oop_is_objArray()) {
2463 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2464 }
2465 oop classloader2;
2466 if (class2->oop_is_instance()) {
2467 classloader2 = InstanceKlass::cast(class2)->class_loader();
2468 } else {
2469 assert(class2->oop_is_typeArray(), "should be type array");
2470 classloader2 = NULL;
2471 }
2472 Symbol* classname2 = class2->name();
2473
2474 return InstanceKlass::is_same_class_package(classloader1, classname1,
2475 classloader2, classname2);
2476 }
2477
2478 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2479 Klass* class1 = this;
2480 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2481 Symbol* classname1 = class1->name();
2482
2483 return InstanceKlass::is_same_class_package(classloader1, classname1,
2484 classloader2, classname2);
2485 }
2486
2487 // return true if two classes are in the same package, classloader
2488 // and classname information is enough to determine a class's package
2489 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2490 oop class_loader2, Symbol* class_name2) {
2491 if (class_loader1 != class_loader2) {
2492 return false;
2493 } else if (class_name1 == class_name2) {
2494 return true; // skip painful bytewise comparison
2495 } else {
2496 ResourceMark rm;
2497
2498 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2499 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2500 // Otherwise, we just compare jbyte values between the strings.
2501 const jbyte *name1 = class_name1->base();
2502 const jbyte *name2 = class_name2->base();
2503
2504 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2505 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2506
2507 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2508 // One of the two doesn't have a package. Only return true
2509 // if the other one also doesn't have a package.
2510 return last_slash1 == last_slash2;
2511 } else {
2512 // Skip over '['s
2513 if (*name1 == '[') {
2514 do {
2515 name1++;
2516 } while (*name1 == '[');
2517 if (*name1 != 'L') {
2518 // Something is terribly wrong. Shouldn't be here.
2519 return false;
2520 }
2521 }
2522 if (*name2 == '[') {
2523 do {
2524 name2++;
2525 } while (*name2 == '[');
2526 if (*name2 != 'L') {
2527 // Something is terribly wrong. Shouldn't be here.
2528 return false;
2529 }
2530 }
2531
2532 // Check that package part is identical
2533 int length1 = last_slash1 - name1;
2534 int length2 = last_slash2 - name2;
2535
2536 return UTF8::equal(name1, length1, name2, length2);
2537 }
2538 }
2539 }
2540
2541 // Returns true iff super_method can be overridden by a method in targetclassname
2542 // See JSL 3rd edition 8.4.6.1
2543 // Assumes name-signature match
2544 // "this" is InstanceKlass of super_method which must exist
2545 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2546 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2547 // Private methods can not be overridden
2548 if (super_method->is_private()) {
2549 return false;
2550 }
2551 // If super method is accessible, then override
2552 if ((super_method->is_protected()) ||
2553 (super_method->is_public())) {
2554 return true;
2555 }
2556 // Package-private methods are not inherited outside of package
2557 assert(super_method->is_package_private(), "must be package private");
2558 return(is_same_class_package(targetclassloader(), targetclassname));
2559 }
2560
2561 /* defined for now in jvm.cpp, for historical reasons *--
2562 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2563 Symbol*& simple_name_result, TRAPS) {
2564 ...
2565 }
2566 */
2567
2568 // tell if two classes have the same enclosing class (at package level)
2569 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2570 Klass* class2_oop, TRAPS) {
2571 if (class2_oop == class1()) return true;
2572 if (!class2_oop->oop_is_instance()) return false;
2573 instanceKlassHandle class2(THREAD, class2_oop);
2574
2575 // must be in same package before we try anything else
2576 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2577 return false;
2578
2579 // As long as there is an outer1.getEnclosingClass,
2580 // shift the search outward.
2581 instanceKlassHandle outer1 = class1;
2582 for (;;) {
2583 // As we walk along, look for equalities between outer1 and class2.
2584 // Eventually, the walks will terminate as outer1 stops
2585 // at the top-level class around the original class.
2586 bool ignore_inner_is_member;
2587 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2588 CHECK_false);
2589 if (next == NULL) break;
2590 if (next == class2()) return true;
2591 outer1 = instanceKlassHandle(THREAD, next);
2592 }
2593
2594 // Now do the same for class2.
2595 instanceKlassHandle outer2 = class2;
2596 for (;;) {
2597 bool ignore_inner_is_member;
2598 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2599 CHECK_false);
2600 if (next == NULL) break;
2601 // Might as well check the new outer against all available values.
2602 if (next == class1()) return true;
2603 if (next == outer1()) return true;
2604 outer2 = instanceKlassHandle(THREAD, next);
2605 }
2606
2607 // If by this point we have not found an equality between the
2608 // two classes, we know they are in separate package members.
2609 return false;
2610 }
2611
2612
2613 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2614 jint access = access_flags().as_int();
2615
2616 // But check if it happens to be member class.
2617 instanceKlassHandle ik(THREAD, this);
2618 InnerClassesIterator iter(ik);
2619 for (; !iter.done(); iter.next()) {
2620 int ioff = iter.inner_class_info_index();
2621 // Inner class attribute can be zero, skip it.
2622 // Strange but true: JVM spec. allows null inner class refs.
2623 if (ioff == 0) continue;
2624
2625 // only look at classes that are already loaded
2626 // since we are looking for the flags for our self.
2627 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2628 if ((ik->name() == inner_name)) {
2629 // This is really a member class.
2630 access = iter.inner_access_flags();
2631 break;
2632 }
2633 }
2634 // Remember to strip ACC_SUPER bit
2635 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2636 }
2637
2638 jint InstanceKlass::jvmti_class_status() const {
2639 jint result = 0;
2640
2641 if (is_linked()) {
2642 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2643 }
2644
2645 if (is_initialized()) {
2646 assert(is_linked(), "Class status is not consistent");
2647 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2648 }
2649 if (is_in_error_state()) {
2650 result |= JVMTI_CLASS_STATUS_ERROR;
2651 }
2652 return result;
2653 }
2654
2655 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2656 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2657 int method_table_offset_in_words = ioe->offset()/wordSize;
2658 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2659 / itableOffsetEntry::size();
2660
2661 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2662 // If the interface isn't implemented by the receiver class,
2663 // the VM should throw IncompatibleClassChangeError.
2664 if (cnt >= nof_interfaces) {
2665 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2666 }
2667
2668 Klass* ik = ioe->interface_klass();
2669 if (ik == holder) break;
2670 }
2671
2672 itableMethodEntry* ime = ioe->first_method_entry(this);
2673 Method* m = ime[index].method();
2674 if (m == NULL) {
2675 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2676 }
2677 return m;
2678 }
2679
2680
2681 #if INCLUDE_JVMTI
2682 // update default_methods for redefineclasses for methods that are
2683 // not yet in the vtable due to concurrent subclass define and superinterface
2684 // redefinition
2685 // Note: those in the vtable, should have been updated via adjust_method_entries
2686 void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods,
2687 int methods_length, bool* trace_name_printed) {
2688 // search the default_methods for uses of either obsolete or EMCP methods
2689 if (default_methods() != NULL) {
2690 for (int j = 0; j < methods_length; j++) {
2691 Method* old_method = old_methods[j];
2692 Method* new_method = new_methods[j];
2693
2694 for (int index = 0; index < default_methods()->length(); index ++) {
2695 if (default_methods()->at(index) == old_method) {
2696 default_methods()->at_put(index, new_method);
2697 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2698 if (!(*trace_name_printed)) {
2699 // RC_TRACE_MESG macro has an embedded ResourceMark
2700 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2701 external_name(),
2702 old_method->method_holder()->external_name()));
2703 *trace_name_printed = true;
2704 }
2705 RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2706 new_method->name()->as_C_string(),
2707 new_method->signature()->as_C_string()));
2708 }
2709 }
2710 }
2711 }
2712 }
2713 }
2714 #endif // INCLUDE_JVMTI
2715
2716 // On-stack replacement stuff
2717 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2718 // only one compilation can be active
2719 NEEDS_CLEANUP
2720 // This is a short non-blocking critical region, so the no safepoint check is ok.
2721 OsrList_lock->lock_without_safepoint_check();
2722 assert(n->is_osr_method(), "wrong kind of nmethod");
2723 n->set_osr_link(osr_nmethods_head());
2724 set_osr_nmethods_head(n);
2725 // Raise the highest osr level if necessary
2726 if (TieredCompilation) {
2727 Method* m = n->method();
2728 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2729 }
2730 // Remember to unlock again
2731 OsrList_lock->unlock();
2732
2733 // Get rid of the osr methods for the same bci that have lower levels.
2734 if (TieredCompilation) {
2735 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2736 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2737 if (inv != NULL && inv->is_in_use()) {
2738 inv->make_not_entrant();
2739 }
2740 }
2741 }
2742 }
2743
2744
2745 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2746 // This is a short non-blocking critical region, so the no safepoint check is ok.
2747 OsrList_lock->lock_without_safepoint_check();
2748 assert(n->is_osr_method(), "wrong kind of nmethod");
2749 nmethod* last = NULL;
2750 nmethod* cur = osr_nmethods_head();
2751 int max_level = CompLevel_none; // Find the max comp level excluding n
2752 Method* m = n->method();
2753 // Search for match
2754 while(cur != NULL && cur != n) {
2755 if (TieredCompilation && m == cur->method()) {
2756 // Find max level before n
2757 max_level = MAX2(max_level, cur->comp_level());
2758 }
2759 last = cur;
2760 cur = cur->osr_link();
2761 }
2762 nmethod* next = NULL;
2763 if (cur == n) {
2764 next = cur->osr_link();
2765 if (last == NULL) {
2766 // Remove first element
2767 set_osr_nmethods_head(next);
2768 } else {
2769 last->set_osr_link(next);
2770 }
2771 }
2772 n->set_osr_link(NULL);
2773 if (TieredCompilation) {
2774 cur = next;
2775 while (cur != NULL) {
2776 // Find max level after n
2777 if (m == cur->method()) {
2778 max_level = MAX2(max_level, cur->comp_level());
2779 }
2780 cur = cur->osr_link();
2781 }
2782 m->set_highest_osr_comp_level(max_level);
2783 }
2784 // Remember to unlock again
2785 OsrList_lock->unlock();
2786 }
2787
2788 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2789 // This is a short non-blocking critical region, so the no safepoint check is ok.
2790 OsrList_lock->lock_without_safepoint_check();
2791 nmethod* osr = osr_nmethods_head();
2792 nmethod* best = NULL;
2793 while (osr != NULL) {
2794 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2795 // There can be a time when a c1 osr method exists but we are waiting
2796 // for a c2 version. When c2 completes its osr nmethod we will trash
2797 // the c1 version and only be able to find the c2 version. However
2798 // while we overflow in the c1 code at back branches we don't want to
2799 // try and switch to the same code as we are already running
2800
2801 if (osr->method() == m &&
2802 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2803 if (match_level) {
2804 if (osr->comp_level() == comp_level) {
2805 // Found a match - return it.
2806 OsrList_lock->unlock();
2807 return osr;
2808 }
2809 } else {
2810 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2811 if (osr->comp_level() == CompLevel_highest_tier) {
2812 // Found the best possible - return it.
2813 OsrList_lock->unlock();
2814 return osr;
2815 }
2816 best = osr;
2817 }
2818 }
2819 }
2820 osr = osr->osr_link();
2821 }
2822 OsrList_lock->unlock();
2823 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2824 return best;
2825 }
2826 return NULL;
2827 }
2828
2829 void InstanceKlass::add_member_name(int index, Handle mem_name) {
2830 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2831 MutexLocker ml(MemberNameTable_lock);
2832 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2833 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2834
2835 if (_member_names == NULL) {
2836 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2837 }
2838 _member_names->add_member_name(index, mem_name_wref);
2839 }
2840
2841 oop InstanceKlass::get_member_name(int index) {
2842 MutexLocker ml(MemberNameTable_lock);
2843 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2844 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2845
2846 if (_member_names == NULL) {
2847 return NULL;
2848 }
2849 oop mem_name =_member_names->get_member_name(index);
2850 return mem_name;
2851 }
2852
2853 // -----------------------------------------------------------------------------------------------------
2854 // Printing
2855
2856 #ifndef PRODUCT
2857
2858 #define BULLET " - "
2859
2860 static const char* state_names[] = {
2861 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2862 };
2863
2864 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2865 for (int i = 0; i < len; i++) {
2866 intptr_t e = start[i];
2867 st->print("%d : " INTPTR_FORMAT, i, e);
2868 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2869 st->print(" ");
2870 ((Metadata*)e)->print_value_on(st);
2871 }
2872 st->cr();
2873 }
2874 }
2875
2876 void InstanceKlass::print_on(outputStream* st) const {
2877 assert(is_klass(), "must be klass");
2878 Klass::print_on(st);
2879
2880 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2881 st->print(BULLET"klass size: %d", size()); st->cr();
2882 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2883 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2884 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2885 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2886 st->print(BULLET"sub: ");
2887 Klass* sub = subklass();
2888 int n;
2889 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2890 if (n < MaxSubklassPrintSize) {
2891 sub->print_value_on(st);
2892 st->print(" ");
2893 }
2894 }
2895 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2896 st->cr();
2897
2898 if (is_interface()) {
2899 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2900 if (nof_implementors() == 1) {
2901 st->print_cr(BULLET"implementor: ");
2902 st->print(" ");
2903 implementor()->print_value_on(st);
2904 st->cr();
2905 }
2906 }
2907
2908 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2909 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2910 if (Verbose || WizardMode) {
2911 Array<Method*>* method_array = methods();
2912 for (int i = 0; i < method_array->length(); i++) {
2913 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2914 }
2915 }
2916 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2917 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2918 if (Verbose && default_methods() != NULL) {
2919 Array<Method*>* method_array = default_methods();
2920 for (int i = 0; i < method_array->length(); i++) {
2921 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2922 }
2923 }
2924 if (default_vtable_indices() != NULL) {
2925 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2926 }
2927 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2928 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2929 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2930 if (class_loader_data() != NULL) {
2931 st->print(BULLET"class loader data: ");
2932 class_loader_data()->print_value_on(st);
2933 st->cr();
2934 }
2935 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2936 if (source_file_name() != NULL) {
2937 st->print(BULLET"source file: ");
2938 source_file_name()->print_value_on(st);
2939 st->cr();
2940 }
2941 if (source_debug_extension() != NULL) {
2942 st->print(BULLET"source debug extension: ");
2943 st->print("%s", source_debug_extension());
2944 st->cr();
2945 }
2946 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2947 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2948 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2949 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2950 {
2951 bool have_pv = false;
2952 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
2953 for (PreviousVersionNode * pv_node = pvw.next_previous_version();
2954 pv_node != NULL; pv_node = pvw.next_previous_version()) {
2955 if (!have_pv)
2956 st->print(BULLET"previous version: ");
2957 have_pv = true;
2958 pv_node->prev_constant_pool()->print_value_on(st);
2959 }
2960 if (have_pv) st->cr();
2961 } // pvw is cleaned up
2962
2963 if (generic_signature() != NULL) {
2964 st->print(BULLET"generic signature: ");
2965 generic_signature()->print_value_on(st);
2966 st->cr();
2967 }
2968 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2969 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2970 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
2971 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2972 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
2973 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2974 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2975 FieldPrinter print_static_field(st);
2976 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2977 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2978 FieldPrinter print_nonstatic_field(st);
2979 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
2980
2981 st->print(BULLET"non-static oop maps: ");
2982 OopMapBlock* map = start_of_nonstatic_oop_maps();
2983 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2984 while (map < end_map) {
2985 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2986 map++;
2987 }
2988 st->cr();
2989 }
2990
2991 #endif //PRODUCT
2992
2993 void InstanceKlass::print_value_on(outputStream* st) const {
2994 assert(is_klass(), "must be klass");
2995 if (Verbose || WizardMode) access_flags().print_on(st);
2996 name()->print_value_on(st);
2997 }
2998
2999 #ifndef PRODUCT
3000
3001 void FieldPrinter::do_field(fieldDescriptor* fd) {
3002 _st->print(BULLET);
3003 if (_obj == NULL) {
3004 fd->print_on(_st);
3005 _st->cr();
3006 } else {
3007 fd->print_on_for(_st, _obj);
3008 _st->cr();
3009 }
3010 }
3011
3012
3013 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3014 Klass::oop_print_on(obj, st);
3015
3016 if (this == SystemDictionary::String_klass()) {
3017 typeArrayOop value = java_lang_String::value(obj);
3018 juint offset = java_lang_String::offset(obj);
3019 juint length = java_lang_String::length(obj);
3020 if (value != NULL &&
3021 value->is_typeArray() &&
3022 offset <= (juint) value->length() &&
3023 offset + length <= (juint) value->length()) {
3024 st->print(BULLET"string: ");
3025 java_lang_String::print(obj, st);
3026 st->cr();
3027 if (!WizardMode) return; // that is enough
3028 }
3029 }
3030
3031 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3032 FieldPrinter print_field(st, obj);
3033 do_nonstatic_fields(&print_field);
3034
3035 if (this == SystemDictionary::Class_klass()) {
3036 st->print(BULLET"signature: ");
3037 java_lang_Class::print_signature(obj, st);
3038 st->cr();
3039 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3040 st->print(BULLET"fake entry for mirror: ");
3041 mirrored_klass->print_value_on_maybe_null(st);
3042 st->cr();
3043 Klass* array_klass = java_lang_Class::array_klass(obj);
3044 st->print(BULLET"fake entry for array: ");
3045 array_klass->print_value_on_maybe_null(st);
3046 st->cr();
3047 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3048 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3049 Klass* real_klass = java_lang_Class::as_Klass(obj);
3050 if (real_klass != NULL && real_klass->oop_is_instance()) {
3051 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3052 }
3053 } else if (this == SystemDictionary::MethodType_klass()) {
3054 st->print(BULLET"signature: ");
3055 java_lang_invoke_MethodType::print_signature(obj, st);
3056 st->cr();
3057 }
3058 }
3059
3060 #endif //PRODUCT
3061
3062 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3063 st->print("a ");
3064 name()->print_value_on(st);
3065 obj->print_address_on(st);
3066 if (this == SystemDictionary::String_klass()
3067 && java_lang_String::value(obj) != NULL) {
3068 ResourceMark rm;
3069 int len = java_lang_String::length(obj);
3070 int plen = (len < 24 ? len : 12);
3071 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3072 st->print(" = \"%s\"", str);
3073 if (len > plen)
3074 st->print("...[%d]", len);
3075 } else if (this == SystemDictionary::Class_klass()) {
3076 Klass* k = java_lang_Class::as_Klass(obj);
3077 st->print(" = ");
3078 if (k != NULL) {
3079 k->print_value_on(st);
3080 } else {
3081 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3082 st->print("%s", tname ? tname : "type?");
3083 }
3084 } else if (this == SystemDictionary::MethodType_klass()) {
3085 st->print(" = ");
3086 java_lang_invoke_MethodType::print_signature(obj, st);
3087 } else if (java_lang_boxing_object::is_instance(obj)) {
3088 st->print(" = ");
3089 java_lang_boxing_object::print(obj, st);
3090 } else if (this == SystemDictionary::LambdaForm_klass()) {
3091 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3092 if (vmentry != NULL) {
3093 st->print(" => ");
3094 vmentry->print_value_on(st);
3095 }
3096 } else if (this == SystemDictionary::MemberName_klass()) {
3097 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3098 if (vmtarget != NULL) {
3099 st->print(" = ");
3100 vmtarget->print_value_on(st);
3101 } else {
3102 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3103 st->print(".");
3104 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3105 }
3106 }
3107 }
3108
3109 const char* InstanceKlass::internal_name() const {
3110 return external_name();
3111 }
3112
3113 #if INCLUDE_SERVICES
3114 // Size Statistics
3115 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3116 Klass::collect_statistics(sz);
3117
3118 sz->_inst_size = HeapWordSize * size_helper();
3119 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
3120 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
3121 sz->_nonstatic_oopmap_bytes = HeapWordSize *
3122 ((is_interface() || is_anonymous()) ?
3123 align_object_offset(nonstatic_oop_map_size()) :
3124 nonstatic_oop_map_size());
3125
3126 int n = 0;
3127 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3128 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3129 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3130 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3131 n += (sz->_fields_bytes = sz->count_array(fields()));
3132 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3133 sz->_ro_bytes += n;
3134
3135 const ConstantPool* cp = constants();
3136 if (cp) {
3137 cp->collect_statistics(sz);
3138 }
3139
3140 const Annotations* anno = annotations();
3141 if (anno) {
3142 anno->collect_statistics(sz);
3143 }
3144
3145 const Array<Method*>* methods_array = methods();
3146 if (methods()) {
3147 for (int i = 0; i < methods_array->length(); i++) {
3148 Method* method = methods_array->at(i);
3149 if (method) {
3150 sz->_method_count ++;
3151 method->collect_statistics(sz);
3152 }
3153 }
3154 }
3155 }
3156 #endif // INCLUDE_SERVICES
3157
3158 // Verification
3159
3160 class VerifyFieldClosure: public OopClosure {
3161 protected:
3162 template <class T> void do_oop_work(T* p) {
3163 oop obj = oopDesc::load_decode_heap_oop(p);
3164 if (!obj->is_oop_or_null()) {
3165 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
3166 Universe::print();
3167 guarantee(false, "boom");
3168 }
3169 }
3170 public:
3171 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3172 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3173 };
3174
3175 void InstanceKlass::verify_on(outputStream* st) {
3176 #ifndef PRODUCT
3177 // Avoid redundant verifies, this really should be in product.
3178 if (_verify_count == Universe::verify_count()) return;
3179 _verify_count = Universe::verify_count();
3180 #endif
3181
3182 // Verify Klass
3183 Klass::verify_on(st);
3184
3185 // Verify that klass is present in ClassLoaderData
3186 guarantee(class_loader_data()->contains_klass(this),
3187 "this class isn't found in class loader data");
3188
3189 // Verify vtables
3190 if (is_linked()) {
3191 ResourceMark rm;
3192 // $$$ This used to be done only for m/s collections. Doing it
3193 // always seemed a valid generalization. (DLD -- 6/00)
3194 vtable()->verify(st);
3195 }
3196
3197 // Verify first subklass
3198 if (subklass() != NULL) {
3199 guarantee(subklass()->is_klass(), "should be klass");
3200 }
3201
3202 // Verify siblings
3203 Klass* super = this->super();
3204 Klass* sib = next_sibling();
3205 if (sib != NULL) {
3206 if (sib == this) {
3207 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3208 }
3209
3210 guarantee(sib->is_klass(), "should be klass");
3211 guarantee(sib->super() == super, "siblings should have same superklass");
3212 }
3213
3214 // Verify implementor fields
3215 Klass* im = implementor();
3216 if (im != NULL) {
3217 guarantee(is_interface(), "only interfaces should have implementor set");
3218 guarantee(im->is_klass(), "should be klass");
3219 guarantee(!im->is_interface() || im == this,
3220 "implementors cannot be interfaces");
3221 }
3222
3223 // Verify local interfaces
3224 if (local_interfaces()) {
3225 Array<Klass*>* local_interfaces = this->local_interfaces();
3226 for (int j = 0; j < local_interfaces->length(); j++) {
3227 Klass* e = local_interfaces->at(j);
3228 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3229 }
3230 }
3231
3232 // Verify transitive interfaces
3233 if (transitive_interfaces() != NULL) {
3234 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3235 for (int j = 0; j < transitive_interfaces->length(); j++) {
3236 Klass* e = transitive_interfaces->at(j);
3237 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3238 }
3239 }
3240
3241 // Verify methods
3242 if (methods() != NULL) {
3243 Array<Method*>* methods = this->methods();
3244 for (int j = 0; j < methods->length(); j++) {
3245 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3246 }
3247 for (int j = 0; j < methods->length() - 1; j++) {
3248 Method* m1 = methods->at(j);
3249 Method* m2 = methods->at(j + 1);
3250 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3251 }
3252 }
3253
3254 // Verify method ordering
3255 if (method_ordering() != NULL) {
3256 Array<int>* method_ordering = this->method_ordering();
3257 int length = method_ordering->length();
3258 if (JvmtiExport::can_maintain_original_method_order() ||
3259 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3260 guarantee(length == methods()->length(), "invalid method ordering length");
3261 jlong sum = 0;
3262 for (int j = 0; j < length; j++) {
3263 int original_index = method_ordering->at(j);
3264 guarantee(original_index >= 0, "invalid method ordering index");
3265 guarantee(original_index < length, "invalid method ordering index");
3266 sum += original_index;
3267 }
3268 // Verify sum of indices 0,1,...,length-1
3269 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3270 } else {
3271 guarantee(length == 0, "invalid method ordering length");
3272 }
3273 }
3274
3275 // Verify default methods
3276 if (default_methods() != NULL) {
3277 Array<Method*>* methods = this->default_methods();
3278 for (int j = 0; j < methods->length(); j++) {
3279 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3280 }
3281 for (int j = 0; j < methods->length() - 1; j++) {
3282 Method* m1 = methods->at(j);
3283 Method* m2 = methods->at(j + 1);
3284 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3285 }
3286 }
3287
3288 // Verify JNI static field identifiers
3289 if (jni_ids() != NULL) {
3290 jni_ids()->verify(this);
3291 }
3292
3293 // Verify other fields
3294 if (array_klasses() != NULL) {
3295 guarantee(array_klasses()->is_klass(), "should be klass");
3296 }
3297 if (constants() != NULL) {
3298 guarantee(constants()->is_constantPool(), "should be constant pool");
3299 }
3300 const Klass* host = host_klass();
3301 if (host != NULL) {
3302 guarantee(host->is_klass(), "should be klass");
3303 }
3304 }
3305
3306 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3307 Klass::oop_verify_on(obj, st);
3308 VerifyFieldClosure blk;
3309 obj->oop_iterate_no_header(&blk);
3310 }
3311
3312
3313 // JNIid class for jfieldIDs only
3314 // Note to reviewers:
3315 // These JNI functions are just moved over to column 1 and not changed
3316 // in the compressed oops workspace.
3317 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3318 _holder = holder;
3319 _offset = offset;
3320 _next = next;
3321 debug_only(_is_static_field_id = false;)
3322 }
3323
3324
3325 JNIid* JNIid::find(int offset) {
3326 JNIid* current = this;
3327 while (current != NULL) {
3328 if (current->offset() == offset) return current;
3329 current = current->next();
3330 }
3331 return NULL;
3332 }
3333
3334 void JNIid::deallocate(JNIid* current) {
3335 while (current != NULL) {
3336 JNIid* next = current->next();
3337 delete current;
3338 current = next;
3339 }
3340 }
3341
3342
3343 void JNIid::verify(Klass* holder) {
3344 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3345 int end_field_offset;
3346 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3347
3348 JNIid* current = this;
3349 while (current != NULL) {
3350 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3351 #ifdef ASSERT
3352 int o = current->offset();
3353 if (current->is_static_field_id()) {
3354 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3355 }
3356 #endif
3357 current = current->next();
3358 }
3359 }
3360
3361
3362 #ifdef ASSERT
3363 void InstanceKlass::set_init_state(ClassState state) {
3364 bool good_state = is_shared() ? (_init_state <= state)
3365 : (_init_state < state);
3366 assert(good_state || state == allocated, "illegal state transition");
3367 _init_state = (u1)state;
3368 }
3369 #endif
3370
3371
3372 // RedefineClasses() support for previous versions:
3373
3374 // Purge previous versions
3375 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3376 if (ik->previous_versions() != NULL) {
3377 // This klass has previous versions so see what we can cleanup
3378 // while it is safe to do so.
3379
3380 int deleted_count = 0; // leave debugging breadcrumbs
3381 int live_count = 0;
3382 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3383 ClassLoaderData::the_null_class_loader_data() :
3384 ik->class_loader_data();
3385
3386 // RC_TRACE macro has an embedded ResourceMark
3387 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3388 ik->external_name(), ik->previous_versions()->length()));
3389
3390 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3391 // check the previous versions array
3392 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3393 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3394 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3395
3396 ConstantPool* pvcp = cp_ref;
3397 if (!pvcp->on_stack()) {
3398 // If the constant pool isn't on stack, none of the methods
3399 // are executing. Delete all the methods, the constant pool and
3400 // and this previous version node.
3401 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3402 if (method_refs != NULL) {
3403 for (int j = method_refs->length() - 1; j >= 0; j--) {
3404 Method* method = method_refs->at(j);
3405 assert(method != NULL, "method ref was unexpectedly cleared");
3406 method_refs->remove_at(j);
3407 // method will be freed with associated class.
3408 }
3409 }
3410 // Remove the constant pool
3411 delete pv_node;
3412 // Since we are traversing the array backwards, we don't have to
3413 // do anything special with the index.
3414 ik->previous_versions()->remove_at(i);
3415 deleted_count++;
3416 continue;
3417 } else {
3418 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3419 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3420 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3421 live_count++;
3422 }
3423
3424 // At least one method is live in this previous version, clean out
3425 // the others or mark them as obsolete.
3426 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3427 if (method_refs != NULL) {
3428 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3429 method_refs->length()));
3430 for (int j = method_refs->length() - 1; j >= 0; j--) {
3431 Method* method = method_refs->at(j);
3432 assert(method != NULL, "method ref was unexpectedly cleared");
3433
3434 // Remove the emcp method if it's not executing
3435 // If it's been made obsolete by a redefinition of a non-emcp
3436 // method, mark it as obsolete but leave it to clean up later.
3437 if (!method->on_stack()) {
3438 method_refs->remove_at(j);
3439 } else if (emcp_method_count == 0) {
3440 method->set_is_obsolete();
3441 } else {
3442 // RC_TRACE macro has an embedded ResourceMark
3443 RC_TRACE(0x00000200,
3444 ("purge: %s(%s): prev method @%d in version @%d is alive",
3445 method->name()->as_C_string(),
3446 method->signature()->as_C_string(), j, i));
3447 if (method->method_data() != NULL) {
3448 // Clean out any weak method links
3449 method->method_data()->clean_weak_method_links();
3450 }
3451 }
3452 }
3453 }
3454 }
3455 assert(ik->previous_versions()->length() == live_count, "sanity check");
3456 RC_TRACE(0x00000200,
3457 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3458 deleted_count));
3459 }
3460
3461 Array<Method*>* methods = ik->methods();
3462 int num_methods = methods->length();
3463 for (int index2 = 0; index2 < num_methods; ++index2) {
3464 if (methods->at(index2)->method_data() != NULL) {
3465 methods->at(index2)->method_data()->clean_weak_method_links();
3466 }
3467 }
3468 }
3469
3470 // External interface for use during class unloading.
3471 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3472 // Call with >0 emcp methods since they are not currently being redefined.
3473 purge_previous_versions_internal(ik, 1);
3474 }
3475
3476
3477 // Potentially add an information node that contains pointers to the
3478 // interesting parts of the previous version of the_class.
3479 // This is also where we clean out any unused references.
3480 // Note that while we delete nodes from the _previous_versions
3481 // array, we never delete the array itself until the klass is
3482 // unloaded. The has_been_redefined() query depends on that fact.
3483 //
3484 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3485 BitMap* emcp_methods, int emcp_method_count) {
3486 assert(Thread::current()->is_VM_thread(),
3487 "only VMThread can add previous versions");
3488
3489 if (_previous_versions == NULL) {
3490 // This is the first previous version so make some space.
3491 // Start with 2 elements under the assumption that the class
3492 // won't be redefined much.
3493 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3494 GrowableArray<PreviousVersionNode *>(2, true);
3495 }
3496
3497 ConstantPool* cp_ref = ikh->constants();
3498
3499 // RC_TRACE macro has an embedded ResourceMark
3500 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3501 "on_stack=%d",
3502 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3503 cp_ref->on_stack()));
3504
3505 // If the constant pool for this previous version of the class
3506 // is not marked as being on the stack, then none of the methods
3507 // in this previous version of the class are on the stack so
3508 // we don't need to create a new PreviousVersionNode. However,
3509 // we still need to examine older previous versions below.
3510 Array<Method*>* old_methods = ikh->methods();
3511
3512 if (cp_ref->on_stack()) {
3513 PreviousVersionNode * pv_node = NULL;
3514 if (emcp_method_count == 0) {
3515 // non-shared ConstantPool gets a reference
3516 pv_node = new PreviousVersionNode(cp_ref, NULL);
3517 RC_TRACE(0x00000400,
3518 ("add: all methods are obsolete; flushing any EMCP refs"));
3519 } else {
3520 int local_count = 0;
3521 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3522 GrowableArray<Method*>(emcp_method_count, true);
3523 for (int i = 0; i < old_methods->length(); i++) {
3524 if (emcp_methods->at(i)) {
3525 // this old method is EMCP. Save it only if it's on the stack
3526 Method* old_method = old_methods->at(i);
3527 if (old_method->on_stack()) {
3528 method_refs->append(old_method);
3529 }
3530 if (++local_count >= emcp_method_count) {
3531 // no more EMCP methods so bail out now
3532 break;
3533 }
3534 }
3535 }
3536 // non-shared ConstantPool gets a reference
3537 pv_node = new PreviousVersionNode(cp_ref, method_refs);
3538 }
3539 // append new previous version.
3540 _previous_versions->append(pv_node);
3541 }
3542
3543 // Since the caller is the VMThread and we are at a safepoint, this
3544 // is a good time to clear out unused references.
3545
3546 RC_TRACE(0x00000400, ("add: previous version length=%d",
3547 _previous_versions->length()));
3548
3549 // Purge previous versions not executing on the stack
3550 purge_previous_versions_internal(this, emcp_method_count);
3551
3552 int obsolete_method_count = old_methods->length() - emcp_method_count;
3553
3554 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3555 _previous_versions->length() > 0) {
3556 // We have a mix of obsolete and EMCP methods so we have to
3557 // clear out any matching EMCP method entries the hard way.
3558 int local_count = 0;
3559 for (int i = 0; i < old_methods->length(); i++) {
3560 if (!emcp_methods->at(i)) {
3561 // only obsolete methods are interesting
3562 Method* old_method = old_methods->at(i);
3563 Symbol* m_name = old_method->name();
3564 Symbol* m_signature = old_method->signature();
3565
3566 // we might not have added the last entry
3567 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3568 // check the previous versions array for non executing obsolete methods
3569 PreviousVersionNode * pv_node = _previous_versions->at(j);
3570
3571 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3572 if (method_refs == NULL) {
3573 // We have run into a PreviousVersion generation where
3574 // all methods were made obsolete during that generation's
3575 // RedefineClasses() operation. At the time of that
3576 // operation, all EMCP methods were flushed so we don't
3577 // have to go back any further.
3578 //
3579 // A NULL method_refs is different than an empty method_refs.
3580 // We cannot infer any optimizations about older generations
3581 // from an empty method_refs for the current generation.
3582 break;
3583 }
3584
3585 for (int k = method_refs->length() - 1; k >= 0; k--) {
3586 Method* method = method_refs->at(k);
3587
3588 if (!method->is_obsolete() &&
3589 method->name() == m_name &&
3590 method->signature() == m_signature) {
3591 // The current RedefineClasses() call has made all EMCP
3592 // versions of this method obsolete so mark it as obsolete
3593 // and remove the reference.
3594 RC_TRACE(0x00000400,
3595 ("add: %s(%s): flush obsolete method @%d in version @%d",
3596 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3597
3598 method->set_is_obsolete();
3599 // Leave obsolete methods on the previous version list to
3600 // clean up later.
3601 break;
3602 }
3603 }
3604
3605 // The previous loop may not find a matching EMCP method, but
3606 // that doesn't mean that we can optimize and not go any
3607 // further back in the PreviousVersion generations. The EMCP
3608 // method for this generation could have already been deleted,
3609 // but there still may be an older EMCP method that has not
3610 // been deleted.
3611 }
3612
3613 if (++local_count >= obsolete_method_count) {
3614 // no more obsolete methods so bail out now
3615 break;
3616 }
3617 }
3618 }
3619 }
3620 } // end add_previous_version()
3621
3622
3623 // Determine if InstanceKlass has a previous version.
3624 bool InstanceKlass::has_previous_version() const {
3625 return (_previous_versions != NULL && _previous_versions->length() > 0);
3626 } // end has_previous_version()
3627
3628
3629 Method* InstanceKlass::method_with_idnum(int idnum) {
3630 Method* m = NULL;
3631 if (idnum < methods()->length()) {
3632 m = methods()->at(idnum);
3633 }
3634 if (m == NULL || m->method_idnum() != idnum) {
3635 for (int index = 0; index < methods()->length(); ++index) {
3636 m = methods()->at(index);
3637 if (m->method_idnum() == idnum) {
3638 return m;
3639 }
3640 }
3641 // None found, return null for the caller to handle.
3642 return NULL;
3643 }
3644 return m;
3645 }
3646
3647 jint InstanceKlass::get_cached_class_file_len() {
3648 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3649 }
3650
3651 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3652 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3653 }
3654
3655
3656 // Construct a PreviousVersionNode entry for the array hung off
3657 // the InstanceKlass.
3658 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3659 GrowableArray<Method*>* prev_EMCP_methods) {
3660
3661 _prev_constant_pool = prev_constant_pool;
3662 _prev_EMCP_methods = prev_EMCP_methods;
3663 }
3664
3665
3666 // Destroy a PreviousVersionNode
3667 PreviousVersionNode::~PreviousVersionNode() {
3668 if (_prev_constant_pool != NULL) {
3669 _prev_constant_pool = NULL;
3670 }
3671
3672 if (_prev_EMCP_methods != NULL) {
3673 delete _prev_EMCP_methods;
3674 }
3675 }
3676
3677 // Construct a helper for walking the previous versions array
3678 PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) {
3679 _thread = thread;
3680 _previous_versions = ik->previous_versions();
3681 _current_index = 0;
3682 _current_p = NULL;
3683 _current_constant_pool_handle = constantPoolHandle(thread, ik->constants());
3684 }
3685
3686
3687 // Return the interesting information for the next previous version
3688 // of the klass. Returns NULL if there are no more previous versions.
3689 PreviousVersionNode* PreviousVersionWalker::next_previous_version() {
3690 if (_previous_versions == NULL) {
3691 // no previous versions so nothing to return
3692 return NULL;
3693 }
3694
3695 _current_p = NULL; // reset to NULL
3696 _current_constant_pool_handle = NULL;
3697
3698 int length = _previous_versions->length();
3699
3700 while (_current_index < length) {
3701 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3702
3703 // Save a handle to the constant pool for this previous version,
3704 // which keeps all the methods from being deallocated.
3705 _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool());
3706 _current_p = pv_node;
3707 return pv_node;
3708 }
3709
3710 return NULL;
3711 } // end next_previous_version()