1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/verifier.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "gc_implementation/shared/markSweep.inline.hpp"
32 #include "gc_interface/collectedHeap.inline.hpp"
33 #include "interpreter/oopMapCache.hpp"
34 #include "interpreter/rewriter.hpp"
35 #include "jvmtifiles/jvmti.h"
36 #include "memory/genOopClosures.inline.hpp"
37 #include "memory/heapInspection.hpp"
38 #include "memory/iterator.inline.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/oopFactory.hpp"
41 #include "oops/fieldStreams.hpp"
42 #include "oops/instanceClassLoaderKlass.hpp"
43 #include "oops/instanceKlass.hpp"
44 #include "oops/instanceMirrorKlass.hpp"
45 #include "oops/instanceOop.hpp"
46 #include "oops/klass.inline.hpp"
47 #include "oops/method.hpp"
48 #include "oops/oop.inline.hpp"
49 #include "oops/symbol.hpp"
50 #include "prims/jvmtiExport.hpp"
51 #include "prims/jvmtiRedefineClassesTrace.hpp"
52 #include "prims/jvmtiRedefineClasses.hpp"
53 #include "prims/jvmtiThreadState.hpp"
54 #include "prims/methodComparator.hpp"
55 #include "runtime/atomic.inline.hpp"
56 #include "runtime/fieldDescriptor.hpp"
57 #include "runtime/handles.inline.hpp"
58 #include "runtime/javaCalls.hpp"
59 #include "runtime/mutexLocker.hpp"
60 #include "runtime/orderAccess.inline.hpp"
61 #include "runtime/thread.inline.hpp"
62 #include "services/classLoadingService.hpp"
63 #include "services/threadService.hpp"
64 #include "utilities/dtrace.hpp"
65 #include "utilities/macros.hpp"
66 #if INCLUDE_ALL_GCS
67 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
68 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
69 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
70 #include "gc_implementation/g1/g1RemSet.inline.hpp"
71 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
72 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
73 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
74 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
75 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
76 #include "oops/oop.pcgc.inline.hpp"
77 #endif // INCLUDE_ALL_GCS
78 #ifdef COMPILER1
79 #include "c1/c1_Compiler.hpp"
80 #endif
81
82 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
83
84 #ifdef DTRACE_ENABLED
85
86
87 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
88 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
89 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
90 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
91 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
92 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
93 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
94 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
95 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
96 { \
97 char* data = NULL; \
98 int len = 0; \
99 Symbol* name = (clss)->name(); \
100 if (name != NULL) { \
101 data = (char*)name->bytes(); \
102 len = name->utf8_length(); \
103 } \
104 HOTSPOT_CLASS_INITIALIZATION_##type( \
105 data, len, (clss)->class_loader(), thread_type); \
106 }
107
108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
109 { \
110 char* data = NULL; \
111 int len = 0; \
112 Symbol* name = (clss)->name(); \
113 if (name != NULL) { \
114 data = (char*)name->bytes(); \
115 len = name->utf8_length(); \
116 } \
117 HOTSPOT_CLASS_INITIALIZATION_##type( \
118 data, len, (clss)->class_loader(), thread_type, wait); \
119 }
120
121 #else // ndef DTRACE_ENABLED
122
123 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
125
126 #endif // ndef DTRACE_ENABLED
127
128 volatile int InstanceKlass::_total_instanceKlass_count = 0;
129
130 InstanceKlass* InstanceKlass::allocate_instance_klass(
131 ClassLoaderData* loader_data,
132 int vtable_len,
133 int itable_len,
134 int static_field_size,
135 int nonstatic_oop_map_size,
136 ReferenceType rt,
137 AccessFlags access_flags,
138 Symbol* name,
139 Klass* super_klass,
140 bool is_anonymous,
141 TRAPS) {
142
143 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
144 access_flags.is_interface(), is_anonymous);
145
146 // Allocation
147 InstanceKlass* ik;
148 if (rt == REF_NONE) {
149 if (name == vmSymbols::java_lang_Class()) {
150 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
151 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
152 access_flags, is_anonymous);
153 } else if (name == vmSymbols::java_lang_ClassLoader() ||
154 (SystemDictionary::ClassLoader_klass_loaded() &&
155 super_klass != NULL &&
156 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
157 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
158 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
159 access_flags, is_anonymous);
160 } else {
161 // normal class
162 ik = new (loader_data, size, THREAD) InstanceKlass(
163 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
164 access_flags, is_anonymous);
165 }
166 } else {
167 // reference klass
168 ik = new (loader_data, size, THREAD) InstanceRefKlass(
169 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
170 access_flags, is_anonymous);
171 }
172
173 // Check for pending exception before adding to the loader data and incrementing
174 // class count. Can get OOM here.
175 if (HAS_PENDING_EXCEPTION) {
176 return NULL;
177 }
178
179 // Add all classes to our internal class loader list here,
180 // including classes in the bootstrap (NULL) class loader.
181 loader_data->add_class(ik);
182
183 Atomic::inc(&_total_instanceKlass_count);
184 return ik;
185 }
186
187
188 // copy method ordering from resource area to Metaspace
189 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
190 if (m != NULL) {
191 // allocate a new array and copy contents (memcpy?)
192 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
193 for (int i = 0; i < m->length(); i++) {
194 _method_ordering->at_put(i, m->at(i));
195 }
196 } else {
197 _method_ordering = Universe::the_empty_int_array();
198 }
199 }
200
201 // create a new array of vtable_indices for default methods
202 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
203 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
204 assert(default_vtable_indices() == NULL, "only create once");
205 set_default_vtable_indices(vtable_indices);
206 return vtable_indices;
207 }
208
209 InstanceKlass::InstanceKlass(int vtable_len,
210 int itable_len,
211 int static_field_size,
212 int nonstatic_oop_map_size,
213 ReferenceType rt,
214 AccessFlags access_flags,
215 bool is_anonymous) {
216 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
217
218 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
219 access_flags.is_interface(), is_anonymous);
220
221 set_vtable_length(vtable_len);
222 set_itable_length(itable_len);
223 set_static_field_size(static_field_size);
224 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
225 set_access_flags(access_flags);
226 _misc_flags = 0; // initialize to zero
227 set_is_anonymous(is_anonymous);
228 assert(size() == iksize, "wrong size for object");
229
230 set_array_klasses(NULL);
231 set_methods(NULL);
232 set_method_ordering(NULL);
233 set_default_methods(NULL);
234 set_default_vtable_indices(NULL);
235 set_local_interfaces(NULL);
236 set_transitive_interfaces(NULL);
237 init_implementor();
238 set_fields(NULL, 0);
239 set_constants(NULL);
240 set_class_loader_data(NULL);
241 set_source_file_name_index(0);
242 set_source_debug_extension(NULL, 0);
243 set_array_name(NULL);
244 set_inner_classes(NULL);
245 set_static_oop_field_count(0);
246 set_nonstatic_field_size(0);
247 set_is_marked_dependent(false);
248 set_has_unloaded_dependent(false);
249 set_init_state(InstanceKlass::allocated);
250 set_init_thread(NULL);
251 set_reference_type(rt);
252 set_oop_map_cache(NULL);
253 set_jni_ids(NULL);
254 set_osr_nmethods_head(NULL);
255 set_breakpoints(NULL);
256 init_previous_versions();
257 set_generic_signature_index(0);
258 release_set_methods_jmethod_ids(NULL);
259 set_annotations(NULL);
260 set_jvmti_cached_class_field_map(NULL);
261 set_initial_method_idnum(0);
262 _dependencies = NULL;
263 set_jvmti_cached_class_field_map(NULL);
264 set_cached_class_file(NULL);
265 set_initial_method_idnum(0);
266 set_minor_version(0);
267 set_major_version(0);
268 NOT_PRODUCT(_verify_count = 0;)
269
270 // initialize the non-header words to zero
271 intptr_t* p = (intptr_t*)this;
272 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
273 p[index] = NULL_WORD;
274 }
275
276 // Set temporary value until parseClassFile updates it with the real instance
277 // size.
278 set_layout_helper(Klass::instance_layout_helper(0, true));
279 }
280
281
282 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
283 Array<Method*>* methods) {
284 if (methods != NULL && methods != Universe::the_empty_method_array() &&
285 !methods->is_shared()) {
286 for (int i = 0; i < methods->length(); i++) {
287 Method* method = methods->at(i);
288 if (method == NULL) continue; // maybe null if error processing
289 // Only want to delete methods that are not executing for RedefineClasses.
290 // The previous version will point to them so they're not totally dangling
291 assert (!method->on_stack(), "shouldn't be called with methods on stack");
292 MetadataFactory::free_metadata(loader_data, method);
293 }
294 MetadataFactory::free_array<Method*>(loader_data, methods);
295 }
296 }
297
298 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
299 Klass* super_klass,
300 Array<Klass*>* local_interfaces,
301 Array<Klass*>* transitive_interfaces) {
302 // Only deallocate transitive interfaces if not empty, same as super class
303 // or same as local interfaces. See code in parseClassFile.
304 Array<Klass*>* ti = transitive_interfaces;
305 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
306 // check that the interfaces don't come from super class
307 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
308 InstanceKlass::cast(super_klass)->transitive_interfaces();
309 if (ti != sti && ti != NULL && !ti->is_shared()) {
310 MetadataFactory::free_array<Klass*>(loader_data, ti);
311 }
312 }
313
314 // local interfaces can be empty
315 if (local_interfaces != Universe::the_empty_klass_array() &&
316 local_interfaces != NULL && !local_interfaces->is_shared()) {
317 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
318 }
319 }
320
321 // This function deallocates the metadata and C heap pointers that the
322 // InstanceKlass points to.
323 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
324
325 // Orphan the mirror first, CMS thinks it's still live.
326 if (java_mirror() != NULL) {
327 java_lang_Class::set_klass(java_mirror(), NULL);
328 }
329
330 // Need to take this class off the class loader data list.
331 loader_data->remove_class(this);
332
333 // The array_klass for this class is created later, after error handling.
334 // For class redefinition, we keep the original class so this scratch class
335 // doesn't have an array class. Either way, assert that there is nothing
336 // to deallocate.
337 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
338
339 // Release C heap allocated data that this might point to, which includes
340 // reference counting symbol names.
341 release_C_heap_structures();
342
343 deallocate_methods(loader_data, methods());
344 set_methods(NULL);
345
346 if (method_ordering() != NULL &&
347 method_ordering() != Universe::the_empty_int_array() &&
348 !method_ordering()->is_shared()) {
349 MetadataFactory::free_array<int>(loader_data, method_ordering());
350 }
351 set_method_ordering(NULL);
352
353 // default methods can be empty
354 if (default_methods() != NULL &&
355 default_methods() != Universe::the_empty_method_array() &&
356 !default_methods()->is_shared()) {
357 MetadataFactory::free_array<Method*>(loader_data, default_methods());
358 }
359 // Do NOT deallocate the default methods, they are owned by superinterfaces.
360 set_default_methods(NULL);
361
362 // default methods vtable indices can be empty
363 if (default_vtable_indices() != NULL &&
364 !default_vtable_indices()->is_shared()) {
365 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
366 }
367 set_default_vtable_indices(NULL);
368
369
370 // This array is in Klass, but remove it with the InstanceKlass since
371 // this place would be the only caller and it can share memory with transitive
372 // interfaces.
373 if (secondary_supers() != NULL &&
374 secondary_supers() != Universe::the_empty_klass_array() &&
375 secondary_supers() != transitive_interfaces() &&
376 !secondary_supers()->is_shared()) {
377 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
378 }
379 set_secondary_supers(NULL);
380
381 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
382 set_transitive_interfaces(NULL);
383 set_local_interfaces(NULL);
384
385 if (fields() != NULL && !fields()->is_shared()) {
386 MetadataFactory::free_array<jushort>(loader_data, fields());
387 }
388 set_fields(NULL, 0);
389
390 // If a method from a redefined class is using this constant pool, don't
391 // delete it, yet. The new class's previous version will point to this.
392 if (constants() != NULL) {
393 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
394 if (!constants()->is_shared()) {
395 MetadataFactory::free_metadata(loader_data, constants());
396 }
397 set_constants(NULL);
398 }
399
400 if (inner_classes() != NULL &&
401 inner_classes() != Universe::the_empty_short_array() &&
402 !inner_classes()->is_shared()) {
403 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
404 }
405 set_inner_classes(NULL);
406
407 // We should deallocate the Annotations instance if it's not in shared spaces.
408 if (annotations() != NULL && !annotations()->is_shared()) {
409 MetadataFactory::free_metadata(loader_data, annotations());
410 }
411 set_annotations(NULL);
412 }
413
414 bool InstanceKlass::should_be_initialized() const {
415 return !is_initialized();
416 }
417
418 klassVtable* InstanceKlass::vtable() const {
419 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
420 }
421
422 klassItable* InstanceKlass::itable() const {
423 return new klassItable(instanceKlassHandle(this));
424 }
425
426 void InstanceKlass::eager_initialize(Thread *thread) {
427 if (!EagerInitialization) return;
428
429 if (this->is_not_initialized()) {
430 // abort if the the class has a class initializer
431 if (this->class_initializer() != NULL) return;
432
433 // abort if it is java.lang.Object (initialization is handled in genesis)
434 Klass* super = this->super();
435 if (super == NULL) return;
436
437 // abort if the super class should be initialized
438 if (!InstanceKlass::cast(super)->is_initialized()) return;
439
440 // call body to expose the this pointer
441 instanceKlassHandle this_k(thread, this);
442 eager_initialize_impl(this_k);
443 }
444 }
445
446 // JVMTI spec thinks there are signers and protection domain in the
447 // instanceKlass. These accessors pretend these fields are there.
448 // The hprof specification also thinks these fields are in InstanceKlass.
449 oop InstanceKlass::protection_domain() const {
450 // return the protection_domain from the mirror
451 return java_lang_Class::protection_domain(java_mirror());
452 }
453
454 // To remove these from requires an incompatible change and CCC request.
455 objArrayOop InstanceKlass::signers() const {
456 // return the signers from the mirror
457 return java_lang_Class::signers(java_mirror());
458 }
459
460 oop InstanceKlass::init_lock() const {
461 // return the init lock from the mirror
462 oop lock = java_lang_Class::init_lock(java_mirror());
463 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
464 "only fully initialized state can have a null lock");
465 return lock;
466 }
467
468 // Set the initialization lock to null so the object can be GC'ed. Any racing
469 // threads to get this lock will see a null lock and will not lock.
470 // That's okay because they all check for initialized state after getting
471 // the lock and return.
472 void InstanceKlass::fence_and_clear_init_lock() {
473 // make sure previous stores are all done, notably the init_state.
474 OrderAccess::storestore();
475 java_lang_Class::set_init_lock(java_mirror(), NULL);
476 assert(!is_not_initialized(), "class must be initialized now");
477 }
478
479 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
480 EXCEPTION_MARK;
481 oop init_lock = this_k->init_lock();
482 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
483
484 // abort if someone beat us to the initialization
485 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized()
486
487 ClassState old_state = this_k->init_state();
488 link_class_impl(this_k, true, THREAD);
489 if (HAS_PENDING_EXCEPTION) {
490 CLEAR_PENDING_EXCEPTION;
491 // Abort if linking the class throws an exception.
492
493 // Use a test to avoid redundantly resetting the state if there's
494 // no change. Set_init_state() asserts that state changes make
495 // progress, whereas here we might just be spinning in place.
496 if( old_state != this_k->_init_state )
497 this_k->set_init_state (old_state);
498 } else {
499 // linking successfull, mark class as initialized
500 this_k->set_init_state (fully_initialized);
501 this_k->fence_and_clear_init_lock();
502 // trace
503 if (TraceClassInitialization) {
504 ResourceMark rm(THREAD);
505 tty->print_cr("[Initialized %s without side effects]", this_k->external_name());
506 }
507 }
508 }
509
510
511 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
512 // process. The step comments refers to the procedure described in that section.
513 // Note: implementation moved to static method to expose the this pointer.
514 void InstanceKlass::initialize(TRAPS) {
515 if (this->should_be_initialized()) {
516 HandleMark hm(THREAD);
517 instanceKlassHandle this_k(THREAD, this);
518 initialize_impl(this_k, CHECK);
519 // Note: at this point the class may be initialized
520 // OR it may be in the state of being initialized
521 // in case of recursive initialization!
522 } else {
523 assert(is_initialized(), "sanity check");
524 }
525 }
526
527
528 bool InstanceKlass::verify_code(
529 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
530 // 1) Verify the bytecodes
531 Verifier::Mode mode =
532 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
533 return Verifier::verify(this_k, mode, this_k->should_verify_class(), CHECK_false);
534 }
535
536
537 // Used exclusively by the shared spaces dump mechanism to prevent
538 // classes mapped into the shared regions in new VMs from appearing linked.
539
540 void InstanceKlass::unlink_class() {
541 assert(is_linked(), "must be linked");
542 _init_state = loaded;
543 }
544
545 void InstanceKlass::link_class(TRAPS) {
546 assert(is_loaded(), "must be loaded");
547 if (!is_linked()) {
548 HandleMark hm(THREAD);
549 instanceKlassHandle this_k(THREAD, this);
550 link_class_impl(this_k, true, CHECK);
551 }
552 }
553
554 // Called to verify that a class can link during initialization, without
555 // throwing a VerifyError.
556 bool InstanceKlass::link_class_or_fail(TRAPS) {
557 assert(is_loaded(), "must be loaded");
558 if (!is_linked()) {
559 HandleMark hm(THREAD);
560 instanceKlassHandle this_k(THREAD, this);
561 link_class_impl(this_k, false, CHECK_false);
562 }
563 return is_linked();
564 }
565
566 bool InstanceKlass::link_class_impl(
567 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
568 // check for error state
569 if (this_k->is_in_error_state()) {
570 ResourceMark rm(THREAD);
571 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
572 this_k->external_name(), false);
573 }
574 // return if already verified
575 if (this_k->is_linked()) {
576 return true;
577 }
578
579 // Timing
580 // timer handles recursion
581 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
582 JavaThread* jt = (JavaThread*)THREAD;
583
584 // link super class before linking this class
585 instanceKlassHandle super(THREAD, this_k->super());
586 if (super.not_null()) {
587 if (super->is_interface()) { // check if super class is an interface
588 ResourceMark rm(THREAD);
589 Exceptions::fthrow(
590 THREAD_AND_LOCATION,
591 vmSymbols::java_lang_IncompatibleClassChangeError(),
592 "class %s has interface %s as super class",
593 this_k->external_name(),
594 super->external_name()
595 );
596 return false;
597 }
598
599 link_class_impl(super, throw_verifyerror, CHECK_false);
600 }
601
602 // link all interfaces implemented by this class before linking this class
603 Array<Klass*>* interfaces = this_k->local_interfaces();
604 int num_interfaces = interfaces->length();
605 for (int index = 0; index < num_interfaces; index++) {
606 HandleMark hm(THREAD);
607 instanceKlassHandle ih(THREAD, interfaces->at(index));
608 link_class_impl(ih, throw_verifyerror, CHECK_false);
609 }
610
611 // in case the class is linked in the process of linking its superclasses
612 if (this_k->is_linked()) {
613 return true;
614 }
615
616 // trace only the link time for this klass that includes
617 // the verification time
618 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
619 ClassLoader::perf_class_link_selftime(),
620 ClassLoader::perf_classes_linked(),
621 jt->get_thread_stat()->perf_recursion_counts_addr(),
622 jt->get_thread_stat()->perf_timers_addr(),
623 PerfClassTraceTime::CLASS_LINK);
624
625 // verification & rewriting
626 {
627 oop init_lock = this_k->init_lock();
628 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
629 // rewritten will have been set if loader constraint error found
630 // on an earlier link attempt
631 // don't verify or rewrite if already rewritten
632
633 if (!this_k->is_linked()) {
634 if (!this_k->is_rewritten()) {
635 {
636 // Timer includes any side effects of class verification (resolution,
637 // etc), but not recursive entry into verify_code().
638 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
639 ClassLoader::perf_class_verify_selftime(),
640 ClassLoader::perf_classes_verified(),
641 jt->get_thread_stat()->perf_recursion_counts_addr(),
642 jt->get_thread_stat()->perf_timers_addr(),
643 PerfClassTraceTime::CLASS_VERIFY);
644 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
645 if (!verify_ok) {
646 return false;
647 }
648 }
649
650 // Just in case a side-effect of verify linked this class already
651 // (which can sometimes happen since the verifier loads classes
652 // using custom class loaders, which are free to initialize things)
653 if (this_k->is_linked()) {
654 return true;
655 }
656
657 // also sets rewritten
658 this_k->rewrite_class(CHECK_false);
659 }
660
661 // relocate jsrs and link methods after they are all rewritten
662 this_k->link_methods(CHECK_false);
663
664 // Initialize the vtable and interface table after
665 // methods have been rewritten since rewrite may
666 // fabricate new Method*s.
667 // also does loader constraint checking
668 if (!this_k()->is_shared()) {
669 ResourceMark rm(THREAD);
670 this_k->vtable()->initialize_vtable(true, CHECK_false);
671 this_k->itable()->initialize_itable(true, CHECK_false);
672 }
673 #ifdef ASSERT
674 else {
675 ResourceMark rm(THREAD);
676 this_k->vtable()->verify(tty, true);
677 // In case itable verification is ever added.
678 // this_k->itable()->verify(tty, true);
679 }
680 #endif
681 this_k->set_init_state(linked);
682 if (JvmtiExport::should_post_class_prepare()) {
683 Thread *thread = THREAD;
684 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
685 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
686 }
687 }
688 }
689 return true;
690 }
691
692
693 // Rewrite the byte codes of all of the methods of a class.
694 // The rewriter must be called exactly once. Rewriting must happen after
695 // verification but before the first method of the class is executed.
696 void InstanceKlass::rewrite_class(TRAPS) {
697 assert(is_loaded(), "must be loaded");
698 instanceKlassHandle this_k(THREAD, this);
699 if (this_k->is_rewritten()) {
700 assert(this_k()->is_shared(), "rewriting an unshared class?");
701 return;
702 }
703 Rewriter::rewrite(this_k, CHECK);
704 this_k->set_rewritten();
705 }
706
707 // Now relocate and link method entry points after class is rewritten.
708 // This is outside is_rewritten flag. In case of an exception, it can be
709 // executed more than once.
710 void InstanceKlass::link_methods(TRAPS) {
711 int len = methods()->length();
712 for (int i = len-1; i >= 0; i--) {
713 methodHandle m(THREAD, methods()->at(i));
714
715 // Set up method entry points for compiler and interpreter .
716 m->link_method(m, CHECK);
717
718 // This is for JVMTI and unrelated to relocator but the last thing we do
719 #ifdef ASSERT
720 if (StressMethodComparator) {
721 ResourceMark rm(THREAD);
722 static int nmc = 0;
723 for (int j = i; j >= 0 && j >= i-4; j--) {
724 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
725 bool z = MethodComparator::methods_EMCP(m(),
726 methods()->at(j));
727 if (j == i && !z) {
728 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
729 assert(z, "method must compare equal to itself");
730 }
731 }
732 }
733 #endif //ASSERT
734 }
735 }
736
737
738 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
739 // Make sure klass is linked (verified) before initialization
740 // A class could already be verified, since it has been reflected upon.
741 this_k->link_class(CHECK);
742
743 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_k()), -1);
744
745 bool wait = false;
746
747 // refer to the JVM book page 47 for description of steps
748 // Step 1
749 {
750 oop init_lock = this_k->init_lock();
751 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
752
753 Thread *self = THREAD; // it's passed the current thread
754
755 // Step 2
756 // If we were to use wait() instead of waitInterruptibly() then
757 // we might end up throwing IE from link/symbol resolution sites
758 // that aren't expected to throw. This would wreak havoc. See 6320309.
759 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
760 wait = true;
761 ol.waitUninterruptibly(CHECK);
762 }
763
764 // Step 3
765 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
766 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_k()), -1,wait);
767 return;
768 }
769
770 // Step 4
771 if (this_k->is_initialized()) {
772 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_k()), -1,wait);
773 return;
774 }
775
776 // Step 5
777 if (this_k->is_in_error_state()) {
778 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_k()), -1,wait);
779 ResourceMark rm(THREAD);
780 const char* desc = "Could not initialize class ";
781 const char* className = this_k->external_name();
782 size_t msglen = strlen(desc) + strlen(className) + 1;
783 char* message = NEW_RESOURCE_ARRAY(char, msglen);
784 if (NULL == message) {
785 // Out of memory: can't create detailed error message
786 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
787 } else {
788 jio_snprintf(message, msglen, "%s%s", desc, className);
789 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
790 }
791 }
792
793 // Step 6
794 this_k->set_init_state(being_initialized);
795 this_k->set_init_thread(self);
796 }
797
798 // Step 7
799 Klass* super_klass = this_k->super();
800 if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) {
801 super_klass->initialize(THREAD);
802
803 if (HAS_PENDING_EXCEPTION) {
804 Handle e(THREAD, PENDING_EXCEPTION);
805 CLEAR_PENDING_EXCEPTION;
806 {
807 EXCEPTION_MARK;
808 this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
809 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
810 }
811 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_k()), -1,wait);
812 THROW_OOP(e());
813 }
814 }
815
816 if (this_k->has_default_methods()) {
817 // Step 7.5: initialize any interfaces which have default methods
818 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
819 Klass* iface = this_k->local_interfaces()->at(i);
820 InstanceKlass* ik = InstanceKlass::cast(iface);
821 if (ik->has_default_methods() && ik->should_be_initialized()) {
822 ik->initialize(THREAD);
823
824 if (HAS_PENDING_EXCEPTION) {
825 Handle e(THREAD, PENDING_EXCEPTION);
826 CLEAR_PENDING_EXCEPTION;
827 {
828 EXCEPTION_MARK;
829 // Locks object, set state, and notify all waiting threads
830 this_k->set_initialization_state_and_notify(
831 initialization_error, THREAD);
832
833 // ignore any exception thrown, superclass initialization error is
834 // thrown below
835 CLEAR_PENDING_EXCEPTION;
836 }
837 DTRACE_CLASSINIT_PROBE_WAIT(
838 super__failed, InstanceKlass::cast(this_k()), -1, wait);
839 THROW_OOP(e());
840 }
841 }
842 }
843 }
844
845 // Step 8
846 {
847 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
848 JavaThread* jt = (JavaThread*)THREAD;
849 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_k()), -1,wait);
850 // Timer includes any side effects of class initialization (resolution,
851 // etc), but not recursive entry into call_class_initializer().
852 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
853 ClassLoader::perf_class_init_selftime(),
854 ClassLoader::perf_classes_inited(),
855 jt->get_thread_stat()->perf_recursion_counts_addr(),
856 jt->get_thread_stat()->perf_timers_addr(),
857 PerfClassTraceTime::CLASS_CLINIT);
858 this_k->call_class_initializer(THREAD);
859 }
860
861 // Step 9
862 if (!HAS_PENDING_EXCEPTION) {
863 this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
864 { ResourceMark rm(THREAD);
865 debug_only(this_k->vtable()->verify(tty, true);)
866 }
867 }
868 else {
869 // Step 10 and 11
870 Handle e(THREAD, PENDING_EXCEPTION);
871 CLEAR_PENDING_EXCEPTION;
872 // JVMTI has already reported the pending exception
873 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
874 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
875 {
876 EXCEPTION_MARK;
877 this_k->set_initialization_state_and_notify(initialization_error, THREAD);
878 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
879 // JVMTI has already reported the pending exception
880 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
881 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
882 }
883 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_k()), -1,wait);
884 if (e->is_a(SystemDictionary::Error_klass())) {
885 THROW_OOP(e());
886 } else {
887 JavaCallArguments args(e);
888 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
889 vmSymbols::throwable_void_signature(),
890 &args);
891 }
892 }
893 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_k()), -1,wait);
894 }
895
896
897 // Note: implementation moved to static method to expose the this pointer.
898 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
899 instanceKlassHandle kh(THREAD, this);
900 set_initialization_state_and_notify_impl(kh, state, CHECK);
901 }
902
903 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
904 oop init_lock = this_k->init_lock();
905 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
906 this_k->set_init_state(state);
907 this_k->fence_and_clear_init_lock();
908 ol.notify_all(CHECK);
909 }
910
911 // The embedded _implementor field can only record one implementor.
912 // When there are more than one implementors, the _implementor field
913 // is set to the interface Klass* itself. Following are the possible
914 // values for the _implementor field:
915 // NULL - no implementor
916 // implementor Klass* - one implementor
917 // self - more than one implementor
918 //
919 // The _implementor field only exists for interfaces.
920 void InstanceKlass::add_implementor(Klass* k) {
921 assert(Compile_lock->owned_by_self(), "");
922 assert(is_interface(), "not interface");
923 // Filter out my subinterfaces.
924 // (Note: Interfaces are never on the subklass list.)
925 if (InstanceKlass::cast(k)->is_interface()) return;
926
927 // Filter out subclasses whose supers already implement me.
928 // (Note: CHA must walk subclasses of direct implementors
929 // in order to locate indirect implementors.)
930 Klass* sk = InstanceKlass::cast(k)->super();
931 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
932 // We only need to check one immediate superclass, since the
933 // implements_interface query looks at transitive_interfaces.
934 // Any supers of the super have the same (or fewer) transitive_interfaces.
935 return;
936
937 Klass* ik = implementor();
938 if (ik == NULL) {
939 set_implementor(k);
940 } else if (ik != this) {
941 // There is already an implementor. Use itself as an indicator of
942 // more than one implementors.
943 set_implementor(this);
944 }
945
946 // The implementor also implements the transitive_interfaces
947 for (int index = 0; index < local_interfaces()->length(); index++) {
948 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
949 }
950 }
951
952 void InstanceKlass::init_implementor() {
953 if (is_interface()) {
954 set_implementor(NULL);
955 }
956 }
957
958
959 void InstanceKlass::process_interfaces(Thread *thread) {
960 // link this class into the implementors list of every interface it implements
961 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
962 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
963 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
964 assert(interf->is_interface(), "expected interface");
965 interf->add_implementor(this);
966 }
967 }
968
969 bool InstanceKlass::can_be_primary_super_slow() const {
970 if (is_interface())
971 return false;
972 else
973 return Klass::can_be_primary_super_slow();
974 }
975
976 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
977 // The secondaries are the implemented interfaces.
978 InstanceKlass* ik = InstanceKlass::cast(this);
979 Array<Klass*>* interfaces = ik->transitive_interfaces();
980 int num_secondaries = num_extra_slots + interfaces->length();
981 if (num_secondaries == 0) {
982 // Must share this for correct bootstrapping!
983 set_secondary_supers(Universe::the_empty_klass_array());
984 return NULL;
985 } else if (num_extra_slots == 0) {
986 // The secondary super list is exactly the same as the transitive interfaces.
987 // Redefine classes has to be careful not to delete this!
988 set_secondary_supers(interfaces);
989 return NULL;
990 } else {
991 // Copy transitive interfaces to a temporary growable array to be constructed
992 // into the secondary super list with extra slots.
993 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
994 for (int i = 0; i < interfaces->length(); i++) {
995 secondaries->push(interfaces->at(i));
996 }
997 return secondaries;
998 }
999 }
1000
1001 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1002 if (k->is_interface()) {
1003 return implements_interface(k);
1004 } else {
1005 return Klass::compute_is_subtype_of(k);
1006 }
1007 }
1008
1009 bool InstanceKlass::implements_interface(Klass* k) const {
1010 if (this == k) return true;
1011 assert(k->is_interface(), "should be an interface class");
1012 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1013 if (transitive_interfaces()->at(i) == k) {
1014 return true;
1015 }
1016 }
1017 return false;
1018 }
1019
1020 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1021 // Verify direct super interface
1022 if (this == k) return true;
1023 assert(k->is_interface(), "should be an interface class");
1024 for (int i = 0; i < local_interfaces()->length(); i++) {
1025 if (local_interfaces()->at(i) == k) {
1026 return true;
1027 }
1028 }
1029 return false;
1030 }
1031
1032 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1033 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1034 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1035 report_java_out_of_memory("Requested array size exceeds VM limit");
1036 JvmtiExport::post_array_size_exhausted();
1037 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1038 }
1039 int size = objArrayOopDesc::object_size(length);
1040 Klass* ak = array_klass(n, CHECK_NULL);
1041 KlassHandle h_ak (THREAD, ak);
1042 objArrayOop o =
1043 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1044 return o;
1045 }
1046
1047 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1048 if (TraceFinalizerRegistration) {
1049 tty->print("Registered ");
1050 i->print_value_on(tty);
1051 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
1052 }
1053 instanceHandle h_i(THREAD, i);
1054 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1055 JavaValue result(T_VOID);
1056 JavaCallArguments args(h_i);
1057 methodHandle mh (THREAD, Universe::finalizer_register_method());
1058 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1059 return h_i();
1060 }
1061
1062 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1063 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1064 int size = size_helper(); // Query before forming handle.
1065
1066 KlassHandle h_k(THREAD, this);
1067
1068 instanceOop i;
1069
1070 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1071 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1072 i = register_finalizer(i, CHECK_NULL);
1073 }
1074 return i;
1075 }
1076
1077 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1078 if (is_interface() || is_abstract()) {
1079 ResourceMark rm(THREAD);
1080 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1081 : vmSymbols::java_lang_InstantiationException(), external_name());
1082 }
1083 if (this == SystemDictionary::Class_klass()) {
1084 ResourceMark rm(THREAD);
1085 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1086 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1087 }
1088 }
1089
1090 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1091 instanceKlassHandle this_k(THREAD, this);
1092 return array_klass_impl(this_k, or_null, n, THREAD);
1093 }
1094
1095 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1096 if (this_k->array_klasses() == NULL) {
1097 if (or_null) return NULL;
1098
1099 ResourceMark rm;
1100 JavaThread *jt = (JavaThread *)THREAD;
1101 {
1102 // Atomic creation of array_klasses
1103 MutexLocker mc(Compile_lock, THREAD); // for vtables
1104 MutexLocker ma(MultiArray_lock, THREAD);
1105
1106 // Check if update has already taken place
1107 if (this_k->array_klasses() == NULL) {
1108 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1109 this_k->set_array_klasses(k);
1110 }
1111 }
1112 }
1113 // _this will always be set at this point
1114 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1115 if (or_null) {
1116 return oak->array_klass_or_null(n);
1117 }
1118 return oak->array_klass(n, CHECK_NULL);
1119 }
1120
1121 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1122 return array_klass_impl(or_null, 1, THREAD);
1123 }
1124
1125 void InstanceKlass::call_class_initializer(TRAPS) {
1126 instanceKlassHandle ik (THREAD, this);
1127 call_class_initializer_impl(ik, THREAD);
1128 }
1129
1130 static int call_class_initializer_impl_counter = 0; // for debugging
1131
1132 Method* InstanceKlass::class_initializer() {
1133 Method* clinit = find_method(
1134 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1135 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1136 return clinit;
1137 }
1138 return NULL;
1139 }
1140
1141 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1142 if (ReplayCompiles &&
1143 (ReplaySuppressInitializers == 1 ||
1144 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1145 // Hide the existence of the initializer for the purpose of replaying the compile
1146 return;
1147 }
1148
1149 methodHandle h_method(THREAD, this_k->class_initializer());
1150 assert(!this_k->is_initialized(), "we cannot initialize twice");
1151 if (TraceClassInitialization) {
1152 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1153 this_k->name()->print_value();
1154 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_k());
1155 }
1156 if (h_method() != NULL) {
1157 JavaCallArguments args; // No arguments
1158 JavaValue result(T_VOID);
1159 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1160 }
1161 }
1162
1163
1164 void InstanceKlass::mask_for(methodHandle method, int bci,
1165 InterpreterOopMap* entry_for) {
1166 // Dirty read, then double-check under a lock.
1167 if (_oop_map_cache == NULL) {
1168 // Otherwise, allocate a new one.
1169 MutexLocker x(OopMapCacheAlloc_lock);
1170 // First time use. Allocate a cache in C heap
1171 if (_oop_map_cache == NULL) {
1172 // Release stores from OopMapCache constructor before assignment
1173 // to _oop_map_cache. C++ compilers on ppc do not emit the
1174 // required memory barrier only because of the volatile
1175 // qualifier of _oop_map_cache.
1176 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1177 }
1178 }
1179 // _oop_map_cache is constant after init; lookup below does is own locking.
1180 _oop_map_cache->lookup(method, bci, entry_for);
1181 }
1182
1183
1184 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1185 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1186 Symbol* f_name = fs.name();
1187 Symbol* f_sig = fs.signature();
1188 if (f_name == name && f_sig == sig) {
1189 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1190 return true;
1191 }
1192 }
1193 return false;
1194 }
1195
1196
1197 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1198 const int n = local_interfaces()->length();
1199 for (int i = 0; i < n; i++) {
1200 Klass* intf1 = local_interfaces()->at(i);
1201 assert(intf1->is_interface(), "just checking type");
1202 // search for field in current interface
1203 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1204 assert(fd->is_static(), "interface field must be static");
1205 return intf1;
1206 }
1207 // search for field in direct superinterfaces
1208 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1209 if (intf2 != NULL) return intf2;
1210 }
1211 // otherwise field lookup fails
1212 return NULL;
1213 }
1214
1215
1216 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1217 // search order according to newest JVM spec (5.4.3.2, p.167).
1218 // 1) search for field in current klass
1219 if (find_local_field(name, sig, fd)) {
1220 return const_cast<InstanceKlass*>(this);
1221 }
1222 // 2) search for field recursively in direct superinterfaces
1223 { Klass* intf = find_interface_field(name, sig, fd);
1224 if (intf != NULL) return intf;
1225 }
1226 // 3) apply field lookup recursively if superclass exists
1227 { Klass* supr = super();
1228 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1229 }
1230 // 4) otherwise field lookup fails
1231 return NULL;
1232 }
1233
1234
1235 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1236 // search order according to newest JVM spec (5.4.3.2, p.167).
1237 // 1) search for field in current klass
1238 if (find_local_field(name, sig, fd)) {
1239 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1240 }
1241 // 2) search for field recursively in direct superinterfaces
1242 if (is_static) {
1243 Klass* intf = find_interface_field(name, sig, fd);
1244 if (intf != NULL) return intf;
1245 }
1246 // 3) apply field lookup recursively if superclass exists
1247 { Klass* supr = super();
1248 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1249 }
1250 // 4) otherwise field lookup fails
1251 return NULL;
1252 }
1253
1254
1255 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1256 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1257 if (fs.offset() == offset) {
1258 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1259 if (fd->is_static() == is_static) return true;
1260 }
1261 }
1262 return false;
1263 }
1264
1265
1266 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1267 Klass* klass = const_cast<InstanceKlass*>(this);
1268 while (klass != NULL) {
1269 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1270 return true;
1271 }
1272 klass = klass->super();
1273 }
1274 return false;
1275 }
1276
1277
1278 void InstanceKlass::methods_do(void f(Method* method)) {
1279 // Methods aren't stable until they are loaded. This can be read outside
1280 // a lock through the ClassLoaderData for profiling
1281 if (!is_loaded()) {
1282 return;
1283 }
1284
1285 int len = methods()->length();
1286 for (int index = 0; index < len; index++) {
1287 Method* m = methods()->at(index);
1288 assert(m->is_method(), "must be method");
1289 f(m);
1290 }
1291 }
1292
1293
1294 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1295 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1296 if (fs.access_flags().is_static()) {
1297 fieldDescriptor& fd = fs.field_descriptor();
1298 cl->do_field(&fd);
1299 }
1300 }
1301 }
1302
1303
1304 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1305 instanceKlassHandle h_this(THREAD, this);
1306 do_local_static_fields_impl(h_this, f, mirror, CHECK);
1307 }
1308
1309
1310 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1311 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1312 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1313 if (fs.access_flags().is_static()) {
1314 fieldDescriptor& fd = fs.field_descriptor();
1315 f(&fd, mirror, CHECK);
1316 }
1317 }
1318 }
1319
1320
1321 static int compare_fields_by_offset(int* a, int* b) {
1322 return a[0] - b[0];
1323 }
1324
1325 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1326 InstanceKlass* super = superklass();
1327 if (super != NULL) {
1328 super->do_nonstatic_fields(cl);
1329 }
1330 fieldDescriptor fd;
1331 int length = java_fields_count();
1332 // In DebugInfo nonstatic fields are sorted by offset.
1333 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1334 int j = 0;
1335 for (int i = 0; i < length; i += 1) {
1336 fd.reinitialize(this, i);
1337 if (!fd.is_static()) {
1338 fields_sorted[j + 0] = fd.offset();
1339 fields_sorted[j + 1] = i;
1340 j += 2;
1341 }
1342 }
1343 if (j > 0) {
1344 length = j;
1345 // _sort_Fn is defined in growableArray.hpp.
1346 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1347 for (int i = 0; i < length; i += 2) {
1348 fd.reinitialize(this, fields_sorted[i + 1]);
1349 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1350 cl->do_field(&fd);
1351 }
1352 }
1353 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1354 }
1355
1356
1357 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1358 if (array_klasses() != NULL)
1359 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1360 }
1361
1362 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1363 if (array_klasses() != NULL)
1364 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1365 }
1366
1367 #ifdef ASSERT
1368 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1369 int len = methods->length();
1370 for (int index = 0; index < len; index++) {
1371 Method* m = methods->at(index);
1372 assert(m->is_method(), "must be method");
1373 if (m->signature() == signature && m->name() == name) {
1374 return index;
1375 }
1376 }
1377 return -1;
1378 }
1379 #endif
1380
1381 static int binary_search(Array<Method*>* methods, Symbol* name) {
1382 int len = methods->length();
1383 // methods are sorted, so do binary search
1384 int l = 0;
1385 int h = len - 1;
1386 while (l <= h) {
1387 int mid = (l + h) >> 1;
1388 Method* m = methods->at(mid);
1389 assert(m->is_method(), "must be method");
1390 int res = m->name()->fast_compare(name);
1391 if (res == 0) {
1392 return mid;
1393 } else if (res < 0) {
1394 l = mid + 1;
1395 } else {
1396 h = mid - 1;
1397 }
1398 }
1399 return -1;
1400 }
1401
1402 // find_method looks up the name/signature in the local methods array
1403 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1404 return find_method_impl(name, signature, false);
1405 }
1406
1407 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const {
1408 return InstanceKlass::find_method_impl(methods(), name, signature, skipping_overpass);
1409 }
1410
1411 // find_instance_method looks up the name/signature in the local methods array
1412 // and skips over static methods
1413 Method* InstanceKlass::find_instance_method(
1414 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1415 Method* meth = InstanceKlass::find_method(methods, name, signature);
1416 if (meth != NULL && meth->is_static()) {
1417 meth = NULL;
1418 }
1419 return meth;
1420 }
1421
1422 // find_method looks up the name/signature in the local methods array
1423 Method* InstanceKlass::find_method(
1424 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1425 return InstanceKlass::find_method_impl(methods, name, signature, false);
1426 }
1427
1428 Method* InstanceKlass::find_method_impl(
1429 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1430 int hit = find_method_index(methods, name, signature, skipping_overpass);
1431 return hit >= 0 ? methods->at(hit): NULL;
1432 }
1433
1434 // Used directly for default_methods to find the index into the
1435 // default_vtable_indices, and indirectly by find_method
1436 // find_method_index looks in the local methods array to return the index
1437 // of the matching name/signature. If, overpass methods are being ignored,
1438 // the search continues to find a potential non-overpass match. This capability
1439 // is important during method resolution to prefer a static method, for example,
1440 // over an overpass method.
1441 int InstanceKlass::find_method_index(
1442 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1443 int hit = binary_search(methods, name);
1444 if (hit != -1) {
1445 Method* m = methods->at(hit);
1446 // Do linear search to find matching signature. First, quick check
1447 // for common case, ignoring overpasses if requested.
1448 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return hit;
1449
1450 // search downwards through overloaded methods
1451 int i;
1452 for (i = hit - 1; i >= 0; --i) {
1453 Method* m = methods->at(i);
1454 assert(m->is_method(), "must be method");
1455 if (m->name() != name) break;
1456 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1457 }
1458 // search upwards
1459 for (i = hit + 1; i < methods->length(); ++i) {
1460 Method* m = methods->at(i);
1461 assert(m->is_method(), "must be method");
1462 if (m->name() != name) break;
1463 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1464 }
1465 // not found
1466 #ifdef ASSERT
1467 int index = skipping_overpass ? -1 : linear_search(methods, name, signature);
1468 assert(index == -1, err_msg("binary search should have found entry %d", index));
1469 #endif
1470 }
1471 return -1;
1472 }
1473 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1474 return find_method_by_name(methods(), name, end);
1475 }
1476
1477 int InstanceKlass::find_method_by_name(
1478 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1479 assert(end_ptr != NULL, "just checking");
1480 int start = binary_search(methods, name);
1481 int end = start + 1;
1482 if (start != -1) {
1483 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1484 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1485 *end_ptr = end;
1486 return start;
1487 }
1488 return -1;
1489 }
1490
1491 // uncached_lookup_method searches both the local class methods array and all
1492 // superclasses methods arrays, skipping any overpass methods in superclasses.
1493 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const {
1494 MethodLookupMode lookup_mode = mode;
1495 Klass* klass = const_cast<InstanceKlass*>(this);
1496 while (klass != NULL) {
1497 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, (lookup_mode == skip_overpass));
1498 if (method != NULL) {
1499 return method;
1500 }
1501 klass = InstanceKlass::cast(klass)->super();
1502 lookup_mode = skip_overpass; // Always ignore overpass methods in superclasses
1503 }
1504 return NULL;
1505 }
1506
1507 #ifdef ASSERT
1508 // search through class hierarchy and return true if this class or
1509 // one of the superclasses was redefined
1510 bool InstanceKlass::has_redefined_this_or_super() const {
1511 const InstanceKlass* klass = this;
1512 while (klass != NULL) {
1513 if (klass->has_been_redefined()) {
1514 return true;
1515 }
1516 klass = InstanceKlass::cast(klass->super());
1517 }
1518 return false;
1519 }
1520 #endif
1521
1522 // lookup a method in the default methods list then in all transitive interfaces
1523 // Do NOT return private or static methods
1524 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1525 Symbol* signature) const {
1526 Method* m = NULL;
1527 if (default_methods() != NULL) {
1528 m = find_method(default_methods(), name, signature);
1529 }
1530 // Look up interfaces
1531 if (m == NULL) {
1532 m = lookup_method_in_all_interfaces(name, signature, normal);
1533 }
1534 return m;
1535 }
1536
1537 // lookup a method in all the interfaces that this class implements
1538 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1539 // They should only be found in the initial InterfaceMethodRef
1540 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1541 Symbol* signature,
1542 MethodLookupMode mode) const {
1543 Array<Klass*>* all_ifs = transitive_interfaces();
1544 int num_ifs = all_ifs->length();
1545 InstanceKlass *ik = NULL;
1546 for (int i = 0; i < num_ifs; i++) {
1547 ik = InstanceKlass::cast(all_ifs->at(i));
1548 Method* m = ik->lookup_method(name, signature);
1549 if (m != NULL && m->is_public() && !m->is_static() &&
1550 ((mode != skip_defaults) || !m->is_default_method())) {
1551 return m;
1552 }
1553 }
1554 return NULL;
1555 }
1556
1557 /* jni_id_for_impl for jfieldIds only */
1558 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1559 MutexLocker ml(JfieldIdCreation_lock);
1560 // Retry lookup after we got the lock
1561 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1562 if (probe == NULL) {
1563 // Slow case, allocate new static field identifier
1564 probe = new JNIid(this_k(), offset, this_k->jni_ids());
1565 this_k->set_jni_ids(probe);
1566 }
1567 return probe;
1568 }
1569
1570
1571 /* jni_id_for for jfieldIds only */
1572 JNIid* InstanceKlass::jni_id_for(int offset) {
1573 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1574 if (probe == NULL) {
1575 probe = jni_id_for_impl(this, offset);
1576 }
1577 return probe;
1578 }
1579
1580 u2 InstanceKlass::enclosing_method_data(int offset) {
1581 Array<jushort>* inner_class_list = inner_classes();
1582 if (inner_class_list == NULL) {
1583 return 0;
1584 }
1585 int length = inner_class_list->length();
1586 if (length % inner_class_next_offset == 0) {
1587 return 0;
1588 } else {
1589 int index = length - enclosing_method_attribute_size;
1590 assert(offset < enclosing_method_attribute_size, "invalid offset");
1591 return inner_class_list->at(index + offset);
1592 }
1593 }
1594
1595 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1596 u2 method_index) {
1597 Array<jushort>* inner_class_list = inner_classes();
1598 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1599 int length = inner_class_list->length();
1600 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1601 int index = length - enclosing_method_attribute_size;
1602 inner_class_list->at_put(
1603 index + enclosing_method_class_index_offset, class_index);
1604 inner_class_list->at_put(
1605 index + enclosing_method_method_index_offset, method_index);
1606 }
1607 }
1608
1609 // Lookup or create a jmethodID.
1610 // This code is called by the VMThread and JavaThreads so the
1611 // locking has to be done very carefully to avoid deadlocks
1612 // and/or other cache consistency problems.
1613 //
1614 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1615 size_t idnum = (size_t)method_h->method_idnum();
1616 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1617 size_t length = 0;
1618 jmethodID id = NULL;
1619
1620 // We use a double-check locking idiom here because this cache is
1621 // performance sensitive. In the normal system, this cache only
1622 // transitions from NULL to non-NULL which is safe because we use
1623 // release_set_methods_jmethod_ids() to advertise the new cache.
1624 // A partially constructed cache should never be seen by a racing
1625 // thread. We also use release_store_ptr() to save a new jmethodID
1626 // in the cache so a partially constructed jmethodID should never be
1627 // seen either. Cache reads of existing jmethodIDs proceed without a
1628 // lock, but cache writes of a new jmethodID requires uniqueness and
1629 // creation of the cache itself requires no leaks so a lock is
1630 // generally acquired in those two cases.
1631 //
1632 // If the RedefineClasses() API has been used, then this cache can
1633 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1634 // Cache creation requires no leaks and we require safety between all
1635 // cache accesses and freeing of the old cache so a lock is generally
1636 // acquired when the RedefineClasses() API has been used.
1637
1638 if (jmeths != NULL) {
1639 // the cache already exists
1640 if (!ik_h->idnum_can_increment()) {
1641 // the cache can't grow so we can just get the current values
1642 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1643 } else {
1644 // cache can grow so we have to be more careful
1645 if (Threads::number_of_threads() == 0 ||
1646 SafepointSynchronize::is_at_safepoint()) {
1647 // we're single threaded or at a safepoint - no locking needed
1648 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1649 } else {
1650 MutexLocker ml(JmethodIdCreation_lock);
1651 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1652 }
1653 }
1654 }
1655 // implied else:
1656 // we need to allocate a cache so default length and id values are good
1657
1658 if (jmeths == NULL || // no cache yet
1659 length <= idnum || // cache is too short
1660 id == NULL) { // cache doesn't contain entry
1661
1662 // This function can be called by the VMThread so we have to do all
1663 // things that might block on a safepoint before grabbing the lock.
1664 // Otherwise, we can deadlock with the VMThread or have a cache
1665 // consistency issue. These vars keep track of what we might have
1666 // to free after the lock is dropped.
1667 jmethodID to_dealloc_id = NULL;
1668 jmethodID* to_dealloc_jmeths = NULL;
1669
1670 // may not allocate new_jmeths or use it if we allocate it
1671 jmethodID* new_jmeths = NULL;
1672 if (length <= idnum) {
1673 // allocate a new cache that might be used
1674 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1675 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1676 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1677 // cache size is stored in element[0], other elements offset by one
1678 new_jmeths[0] = (jmethodID)size;
1679 }
1680
1681 // allocate a new jmethodID that might be used
1682 jmethodID new_id = NULL;
1683 if (method_h->is_old() && !method_h->is_obsolete()) {
1684 // The method passed in is old (but not obsolete), we need to use the current version
1685 Method* current_method = ik_h->method_with_idnum((int)idnum);
1686 assert(current_method != NULL, "old and but not obsolete, so should exist");
1687 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1688 } else {
1689 // It is the current version of the method or an obsolete method,
1690 // use the version passed in
1691 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1692 }
1693
1694 if (Threads::number_of_threads() == 0 ||
1695 SafepointSynchronize::is_at_safepoint()) {
1696 // we're single threaded or at a safepoint - no locking needed
1697 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1698 &to_dealloc_id, &to_dealloc_jmeths);
1699 } else {
1700 MutexLocker ml(JmethodIdCreation_lock);
1701 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1702 &to_dealloc_id, &to_dealloc_jmeths);
1703 }
1704
1705 // The lock has been dropped so we can free resources.
1706 // Free up either the old cache or the new cache if we allocated one.
1707 if (to_dealloc_jmeths != NULL) {
1708 FreeHeap(to_dealloc_jmeths);
1709 }
1710 // free up the new ID since it wasn't needed
1711 if (to_dealloc_id != NULL) {
1712 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1713 }
1714 }
1715 return id;
1716 }
1717
1718
1719 // Common code to fetch the jmethodID from the cache or update the
1720 // cache with the new jmethodID. This function should never do anything
1721 // that causes the caller to go to a safepoint or we can deadlock with
1722 // the VMThread or have cache consistency issues.
1723 //
1724 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1725 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1726 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1727 jmethodID** to_dealloc_jmeths_p) {
1728 assert(new_id != NULL, "sanity check");
1729 assert(to_dealloc_id_p != NULL, "sanity check");
1730 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1731 assert(Threads::number_of_threads() == 0 ||
1732 SafepointSynchronize::is_at_safepoint() ||
1733 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1734
1735 // reacquire the cache - we are locked, single threaded or at a safepoint
1736 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1737 jmethodID id = NULL;
1738 size_t length = 0;
1739
1740 if (jmeths == NULL || // no cache yet
1741 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1742 if (jmeths != NULL) {
1743 // copy any existing entries from the old cache
1744 for (size_t index = 0; index < length; index++) {
1745 new_jmeths[index+1] = jmeths[index+1];
1746 }
1747 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1748 }
1749 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1750 } else {
1751 // fetch jmethodID (if any) from the existing cache
1752 id = jmeths[idnum+1];
1753 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1754 }
1755 if (id == NULL) {
1756 // No matching jmethodID in the existing cache or we have a new
1757 // cache or we just grew the cache. This cache write is done here
1758 // by the first thread to win the foot race because a jmethodID
1759 // needs to be unique once it is generally available.
1760 id = new_id;
1761
1762 // The jmethodID cache can be read while unlocked so we have to
1763 // make sure the new jmethodID is complete before installing it
1764 // in the cache.
1765 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1766 } else {
1767 *to_dealloc_id_p = new_id; // save new id for later delete
1768 }
1769 return id;
1770 }
1771
1772
1773 // Common code to get the jmethodID cache length and the jmethodID
1774 // value at index idnum if there is one.
1775 //
1776 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1777 size_t idnum, size_t *length_p, jmethodID* id_p) {
1778 assert(cache != NULL, "sanity check");
1779 assert(length_p != NULL, "sanity check");
1780 assert(id_p != NULL, "sanity check");
1781
1782 // cache size is stored in element[0], other elements offset by one
1783 *length_p = (size_t)cache[0];
1784 if (*length_p <= idnum) { // cache is too short
1785 *id_p = NULL;
1786 } else {
1787 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1788 }
1789 }
1790
1791
1792 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1793 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1794 size_t idnum = (size_t)method->method_idnum();
1795 jmethodID* jmeths = methods_jmethod_ids_acquire();
1796 size_t length; // length assigned as debugging crumb
1797 jmethodID id = NULL;
1798 if (jmeths != NULL && // If there is a cache
1799 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1800 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1801 }
1802 return id;
1803 }
1804
1805 int nmethodBucket::decrement() {
1806 return Atomic::add(-1, (volatile int *)&_count);
1807 }
1808
1809 //
1810 // Walk the list of dependent nmethods searching for nmethods which
1811 // are dependent on the changes that were passed in and mark them for
1812 // deoptimization. Returns the number of nmethods found.
1813 //
1814 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1815 assert_locked_or_safepoint(CodeCache_lock);
1816 int found = 0;
1817 nmethodBucket* b = _dependencies;
1818 while (b != NULL) {
1819 nmethod* nm = b->get_nmethod();
1820 // since dependencies aren't removed until an nmethod becomes a zombie,
1821 // the dependency list may contain nmethods which aren't alive.
1822 if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1823 if (TraceDependencies) {
1824 ResourceMark rm;
1825 tty->print_cr("Marked for deoptimization");
1826 tty->print_cr(" context = %s", this->external_name());
1827 changes.print();
1828 nm->print();
1829 nm->print_dependencies();
1830 }
1831 nm->mark_for_deoptimization();
1832 found++;
1833 }
1834 b = b->next();
1835 }
1836 return found;
1837 }
1838
1839 void InstanceKlass::clean_dependent_nmethods() {
1840 assert_locked_or_safepoint(CodeCache_lock);
1841
1842 if (has_unloaded_dependent()) {
1843 nmethodBucket* b = _dependencies;
1844 nmethodBucket* last = NULL;
1845 while (b != NULL) {
1846 assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
1847
1848 nmethodBucket* next = b->next();
1849
1850 if (b->count() == 0) {
1851 if (last == NULL) {
1852 _dependencies = next;
1853 } else {
1854 last->set_next(next);
1855 }
1856 delete b;
1857 // last stays the same.
1858 } else {
1859 last = b;
1860 }
1861
1862 b = next;
1863 }
1864 set_has_unloaded_dependent(false);
1865 }
1866 #ifdef ASSERT
1867 else {
1868 // Verification
1869 for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) {
1870 assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
1871 assert(b->count() != 0, "empty buckets need to be cleaned");
1872 }
1873 }
1874 #endif
1875 }
1876
1877 //
1878 // Add an nmethodBucket to the list of dependencies for this nmethod.
1879 // It's possible that an nmethod has multiple dependencies on this klass
1880 // so a count is kept for each bucket to guarantee that creation and
1881 // deletion of dependencies is consistent.
1882 //
1883 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1884 assert_locked_or_safepoint(CodeCache_lock);
1885 nmethodBucket* b = _dependencies;
1886 nmethodBucket* last = NULL;
1887 while (b != NULL) {
1888 if (nm == b->get_nmethod()) {
1889 b->increment();
1890 return;
1891 }
1892 b = b->next();
1893 }
1894 _dependencies = new nmethodBucket(nm, _dependencies);
1895 }
1896
1897
1898 //
1899 // Decrement count of the nmethod in the dependency list and remove
1900 // the bucket competely when the count goes to 0. This method must
1901 // find a corresponding bucket otherwise there's a bug in the
1902 // recording of dependecies.
1903 //
1904 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1905 assert_locked_or_safepoint(CodeCache_lock);
1906 nmethodBucket* b = _dependencies;
1907 nmethodBucket* last = NULL;
1908 while (b != NULL) {
1909 if (nm == b->get_nmethod()) {
1910 int val = b->decrement();
1911 guarantee(val >= 0, err_msg("Underflow: %d", val));
1912 if (val == 0) {
1913 set_has_unloaded_dependent(true);
1914 }
1915 return;
1916 }
1917 last = b;
1918 b = b->next();
1919 }
1920 #ifdef ASSERT
1921 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1922 nm->print();
1923 #endif // ASSERT
1924 ShouldNotReachHere();
1925 }
1926
1927
1928 #ifndef PRODUCT
1929 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1930 nmethodBucket* b = _dependencies;
1931 int idx = 0;
1932 while (b != NULL) {
1933 nmethod* nm = b->get_nmethod();
1934 tty->print("[%d] count=%d { ", idx++, b->count());
1935 if (!verbose) {
1936 nm->print_on(tty, "nmethod");
1937 tty->print_cr(" } ");
1938 } else {
1939 nm->print();
1940 nm->print_dependencies();
1941 tty->print_cr("--- } ");
1942 }
1943 b = b->next();
1944 }
1945 }
1946
1947
1948 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1949 nmethodBucket* b = _dependencies;
1950 while (b != NULL) {
1951 if (nm == b->get_nmethod()) {
1952 #ifdef ASSERT
1953 int count = b->count();
1954 assert(count >= 0, err_msg("count shouldn't be negative: %d", count));
1955 #endif
1956 return true;
1957 }
1958 b = b->next();
1959 }
1960 return false;
1961 }
1962 #endif //PRODUCT
1963
1964
1965 // Garbage collection
1966
1967 #ifdef ASSERT
1968 template <class T> void assert_is_in(T *p) {
1969 T heap_oop = oopDesc::load_heap_oop(p);
1970 if (!oopDesc::is_null(heap_oop)) {
1971 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1972 assert(Universe::heap()->is_in(o), "should be in heap");
1973 }
1974 }
1975 template <class T> void assert_is_in_closed_subset(T *p) {
1976 T heap_oop = oopDesc::load_heap_oop(p);
1977 if (!oopDesc::is_null(heap_oop)) {
1978 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1979 assert(Universe::heap()->is_in_closed_subset(o),
1980 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
1981 }
1982 }
1983 template <class T> void assert_is_in_reserved(T *p) {
1984 T heap_oop = oopDesc::load_heap_oop(p);
1985 if (!oopDesc::is_null(heap_oop)) {
1986 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1987 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1988 }
1989 }
1990 template <class T> void assert_nothing(T *p) {}
1991
1992 #else
1993 template <class T> void assert_is_in(T *p) {}
1994 template <class T> void assert_is_in_closed_subset(T *p) {}
1995 template <class T> void assert_is_in_reserved(T *p) {}
1996 template <class T> void assert_nothing(T *p) {}
1997 #endif // ASSERT
1998
1999 //
2000 // Macros that iterate over areas of oops which are specialized on type of
2001 // oop pointer either narrow or wide, depending on UseCompressedOops
2002 //
2003 // Parameters are:
2004 // T - type of oop to point to (either oop or narrowOop)
2005 // start_p - starting pointer for region to iterate over
2006 // count - number of oops or narrowOops to iterate over
2007 // do_oop - action to perform on each oop (it's arbitrary C code which
2008 // makes it more efficient to put in a macro rather than making
2009 // it a template function)
2010 // assert_fn - assert function which is template function because performance
2011 // doesn't matter when enabled.
2012 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
2013 T, start_p, count, do_oop, \
2014 assert_fn) \
2015 { \
2016 T* p = (T*)(start_p); \
2017 T* const end = p + (count); \
2018 while (p < end) { \
2019 (assert_fn)(p); \
2020 do_oop; \
2021 ++p; \
2022 } \
2023 }
2024
2025 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
2026 T, start_p, count, do_oop, \
2027 assert_fn) \
2028 { \
2029 T* const start = (T*)(start_p); \
2030 T* p = start + (count); \
2031 while (start < p) { \
2032 --p; \
2033 (assert_fn)(p); \
2034 do_oop; \
2035 } \
2036 }
2037
2038 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
2039 T, start_p, count, low, high, \
2040 do_oop, assert_fn) \
2041 { \
2042 T* const l = (T*)(low); \
2043 T* const h = (T*)(high); \
2044 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
2045 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
2046 "bounded region must be properly aligned"); \
2047 T* p = (T*)(start_p); \
2048 T* end = p + (count); \
2049 if (p < l) p = l; \
2050 if (end > h) end = h; \
2051 while (p < end) { \
2052 (assert_fn)(p); \
2053 do_oop; \
2054 ++p; \
2055 } \
2056 }
2057
2058
2059 // The following macros call specialized macros, passing either oop or
2060 // narrowOop as the specialization type. These test the UseCompressedOops
2061 // flag.
2062 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
2063 { \
2064 /* Compute oopmap block range. The common case \
2065 is nonstatic_oop_map_size == 1. */ \
2066 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2067 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2068 if (UseCompressedOops) { \
2069 while (map < end_map) { \
2070 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
2071 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2072 do_oop, assert_fn) \
2073 ++map; \
2074 } \
2075 } else { \
2076 while (map < end_map) { \
2077 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
2078 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2079 do_oop, assert_fn) \
2080 ++map; \
2081 } \
2082 } \
2083 }
2084
2085 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
2086 { \
2087 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
2088 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
2089 if (UseCompressedOops) { \
2090 while (start_map < map) { \
2091 --map; \
2092 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
2093 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2094 do_oop, assert_fn) \
2095 } \
2096 } else { \
2097 while (start_map < map) { \
2098 --map; \
2099 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
2100 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2101 do_oop, assert_fn) \
2102 } \
2103 } \
2104 }
2105
2106 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
2107 assert_fn) \
2108 { \
2109 /* Compute oopmap block range. The common case is \
2110 nonstatic_oop_map_size == 1, so we accept the \
2111 usually non-existent extra overhead of examining \
2112 all the maps. */ \
2113 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2114 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2115 if (UseCompressedOops) { \
2116 while (map < end_map) { \
2117 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
2118 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2119 low, high, \
2120 do_oop, assert_fn) \
2121 ++map; \
2122 } \
2123 } else { \
2124 while (map < end_map) { \
2125 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2126 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2127 low, high, \
2128 do_oop, assert_fn) \
2129 ++map; \
2130 } \
2131 } \
2132 }
2133
2134 void InstanceKlass::oop_follow_contents(oop obj) {
2135 assert(obj != NULL, "can't follow the content of NULL object");
2136 MarkSweep::follow_klass(obj->klass());
2137 InstanceKlass_OOP_MAP_ITERATE( \
2138 obj, \
2139 MarkSweep::mark_and_push(p), \
2140 assert_is_in_closed_subset)
2141 }
2142
2143 #if INCLUDE_ALL_GCS
2144 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2145 oop obj) {
2146 assert(obj != NULL, "can't follow the content of NULL object");
2147 PSParallelCompact::follow_klass(cm, obj->klass());
2148 // Only mark the header and let the scan of the meta-data mark
2149 // everything else.
2150 InstanceKlass_OOP_MAP_ITERATE( \
2151 obj, \
2152 PSParallelCompact::mark_and_push(cm, p), \
2153 assert_is_in)
2154 }
2155 #endif // INCLUDE_ALL_GCS
2156
2157 // closure's do_metadata() method dictates whether the given closure should be
2158 // applied to the klass ptr in the object header.
2159
2160 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2161 \
2162 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2163 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2164 /* header */ \
2165 if_do_metadata_checked(closure, nv_suffix) { \
2166 closure->do_klass##nv_suffix(obj->klass()); \
2167 } \
2168 InstanceKlass_OOP_MAP_ITERATE( \
2169 obj, \
2170 SpecializationStats:: \
2171 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2172 (closure)->do_oop##nv_suffix(p), \
2173 assert_is_in_closed_subset) \
2174 return size_helper(); \
2175 }
2176
2177 #if INCLUDE_ALL_GCS
2178 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2179 \
2180 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2181 OopClosureType* closure) { \
2182 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2183 \
2184 assert_should_ignore_metadata(closure, nv_suffix); \
2185 \
2186 /* instance variables */ \
2187 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2188 obj, \
2189 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2190 (closure)->do_oop##nv_suffix(p), \
2191 assert_is_in_closed_subset) \
2192 return size_helper(); \
2193 }
2194 #endif // INCLUDE_ALL_GCS
2195
2196 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2197 \
2198 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2199 OopClosureType* closure, \
2200 MemRegion mr) { \
2201 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2202 if_do_metadata_checked(closure, nv_suffix) { \
2203 if (mr.contains(obj)) { \
2204 closure->do_klass##nv_suffix(obj->klass()); \
2205 } \
2206 } \
2207 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2208 obj, mr.start(), mr.end(), \
2209 (closure)->do_oop##nv_suffix(p), \
2210 assert_is_in_closed_subset) \
2211 return size_helper(); \
2212 }
2213
2214 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2215 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2216 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2217 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2218 #if INCLUDE_ALL_GCS
2219 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2220 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2221 #endif // INCLUDE_ALL_GCS
2222
2223 int InstanceKlass::oop_adjust_pointers(oop obj) {
2224 int size = size_helper();
2225 InstanceKlass_OOP_MAP_ITERATE( \
2226 obj, \
2227 MarkSweep::adjust_pointer(p), \
2228 assert_is_in)
2229 return size;
2230 }
2231
2232 #if INCLUDE_ALL_GCS
2233 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2234 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2235 obj, \
2236 if (PSScavenge::should_scavenge(p)) { \
2237 pm->claim_or_forward_depth(p); \
2238 }, \
2239 assert_nothing )
2240 }
2241
2242 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2243 int size = size_helper();
2244 InstanceKlass_OOP_MAP_ITERATE( \
2245 obj, \
2246 PSParallelCompact::adjust_pointer(p), \
2247 assert_is_in)
2248 return size;
2249 }
2250
2251 #endif // INCLUDE_ALL_GCS
2252
2253 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2254 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2255 if (is_interface()) {
2256 if (ClassUnloading) {
2257 Klass* impl = implementor();
2258 if (impl != NULL) {
2259 if (!impl->is_loader_alive(is_alive)) {
2260 // remove this guy
2261 Klass** klass = adr_implementor();
2262 assert(klass != NULL, "null klass");
2263 if (klass != NULL) {
2264 *klass = NULL;
2265 }
2266 }
2267 }
2268 }
2269 }
2270 }
2271
2272 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2273 for (int m = 0; m < methods()->length(); m++) {
2274 MethodData* mdo = methods()->at(m)->method_data();
2275 if (mdo != NULL) {
2276 mdo->clean_method_data(is_alive);
2277 }
2278 }
2279 }
2280
2281
2282 static void remove_unshareable_in_class(Klass* k) {
2283 // remove klass's unshareable info
2284 k->remove_unshareable_info();
2285 }
2286
2287 void InstanceKlass::remove_unshareable_info() {
2288 Klass::remove_unshareable_info();
2289 // Unlink the class
2290 if (is_linked()) {
2291 unlink_class();
2292 }
2293 init_implementor();
2294
2295 constants()->remove_unshareable_info();
2296
2297 for (int i = 0; i < methods()->length(); i++) {
2298 Method* m = methods()->at(i);
2299 m->remove_unshareable_info();
2300 }
2301
2302 // do array classes also.
2303 array_klasses_do(remove_unshareable_in_class);
2304 }
2305
2306 static void restore_unshareable_in_class(Klass* k, TRAPS) {
2307 // Array classes have null protection domain.
2308 // --> see ArrayKlass::complete_create_array_klass()
2309 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2310 }
2311
2312 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2313 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2314 instanceKlassHandle ik(THREAD, this);
2315
2316 Array<Method*>* methods = ik->methods();
2317 int num_methods = methods->length();
2318 for (int index2 = 0; index2 < num_methods; ++index2) {
2319 methodHandle m(THREAD, methods->at(index2));
2320 m->restore_unshareable_info(CHECK);
2321 }
2322 if (JvmtiExport::has_redefined_a_class()) {
2323 // Reinitialize vtable because RedefineClasses may have changed some
2324 // entries in this vtable for super classes so the CDS vtable might
2325 // point to old or obsolete entries. RedefineClasses doesn't fix up
2326 // vtables in the shared system dictionary, only the main one.
2327 // It also redefines the itable too so fix that too.
2328 ResourceMark rm(THREAD);
2329 ik->vtable()->initialize_vtable(false, CHECK);
2330 ik->itable()->initialize_itable(false, CHECK);
2331 }
2332
2333 // restore constant pool resolved references
2334 ik->constants()->restore_unshareable_info(CHECK);
2335
2336 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2337 }
2338
2339 // returns true IFF is_in_error_state() has been changed as a result of this call.
2340 bool InstanceKlass::check_sharing_error_state() {
2341 assert(DumpSharedSpaces, "should only be called during dumping");
2342 bool old_state = is_in_error_state();
2343
2344 if (!is_in_error_state()) {
2345 bool bad = false;
2346 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2347 if (sup->is_in_error_state()) {
2348 bad = true;
2349 break;
2350 }
2351 }
2352 if (!bad) {
2353 Array<Klass*>* interfaces = transitive_interfaces();
2354 for (int i = 0; i < interfaces->length(); i++) {
2355 Klass* iface = interfaces->at(i);
2356 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2357 bad = true;
2358 break;
2359 }
2360 }
2361 }
2362
2363 if (bad) {
2364 set_in_error_state();
2365 }
2366 }
2367
2368 return (old_state != is_in_error_state());
2369 }
2370
2371 static void clear_all_breakpoints(Method* m) {
2372 m->clear_all_breakpoints();
2373 }
2374
2375
2376 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2377 // notify the debugger
2378 if (JvmtiExport::should_post_class_unload()) {
2379 JvmtiExport::post_class_unload(ik);
2380 }
2381
2382 // notify ClassLoadingService of class unload
2383 ClassLoadingService::notify_class_unloaded(ik);
2384 }
2385
2386 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2387 // Clean up C heap
2388 ik->release_C_heap_structures();
2389 ik->constants()->release_C_heap_structures();
2390 }
2391
2392 void InstanceKlass::release_C_heap_structures() {
2393
2394 // Can't release the constant pool here because the constant pool can be
2395 // deallocated separately from the InstanceKlass for default methods and
2396 // redefine classes.
2397
2398 // Deallocate oop map cache
2399 if (_oop_map_cache != NULL) {
2400 delete _oop_map_cache;
2401 _oop_map_cache = NULL;
2402 }
2403
2404 // Deallocate JNI identifiers for jfieldIDs
2405 JNIid::deallocate(jni_ids());
2406 set_jni_ids(NULL);
2407
2408 jmethodID* jmeths = methods_jmethod_ids_acquire();
2409 if (jmeths != (jmethodID*)NULL) {
2410 release_set_methods_jmethod_ids(NULL);
2411 FreeHeap(jmeths);
2412 }
2413
2414 // Deallocate MemberNameTable
2415 {
2416 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2417 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2418 MemberNameTable* mnt = member_names();
2419 if (mnt != NULL) {
2420 delete mnt;
2421 set_member_names(NULL);
2422 }
2423 }
2424
2425 // release dependencies
2426 nmethodBucket* b = _dependencies;
2427 _dependencies = NULL;
2428 while (b != NULL) {
2429 nmethodBucket* next = b->next();
2430 delete b;
2431 b = next;
2432 }
2433
2434 // Deallocate breakpoint records
2435 if (breakpoints() != 0x0) {
2436 methods_do(clear_all_breakpoints);
2437 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2438 }
2439
2440 // deallocate information about previous versions
2441 if (_previous_versions != NULL) {
2442 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2443 PreviousVersionNode * pv_node = _previous_versions->at(i);
2444 delete pv_node;
2445 }
2446 delete _previous_versions;
2447 _previous_versions = NULL;
2448 }
2449
2450 // deallocate the cached class file
2451 if (_cached_class_file != NULL) {
2452 os::free(_cached_class_file, mtClass);
2453 _cached_class_file = NULL;
2454 }
2455
2456 // Decrement symbol reference counts associated with the unloaded class.
2457 if (_name != NULL) _name->decrement_refcount();
2458 // unreference array name derived from this class name (arrays of an unloaded
2459 // class can't be referenced anymore).
2460 if (_array_name != NULL) _array_name->decrement_refcount();
2461 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2462
2463 assert(_total_instanceKlass_count >= 1, "Sanity check");
2464 Atomic::dec(&_total_instanceKlass_count);
2465 }
2466
2467 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2468 if (array == NULL) {
2469 _source_debug_extension = NULL;
2470 } else {
2471 // Adding one to the attribute length in order to store a null terminator
2472 // character could cause an overflow because the attribute length is
2473 // already coded with an u4 in the classfile, but in practice, it's
2474 // unlikely to happen.
2475 assert((length+1) > length, "Overflow checking");
2476 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2477 for (int i = 0; i < length; i++) {
2478 sde[i] = array[i];
2479 }
2480 sde[length] = '\0';
2481 _source_debug_extension = sde;
2482 }
2483 }
2484
2485 address InstanceKlass::static_field_addr(int offset) {
2486 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2487 }
2488
2489
2490 const char* InstanceKlass::signature_name() const {
2491 int hash_len = 0;
2492 char hash_buf[40];
2493
2494 // If this is an anonymous class, append a hash to make the name unique
2495 if (is_anonymous()) {
2496 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2497 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
2498 hash_len = (int)strlen(hash_buf);
2499 }
2500
2501 // Get the internal name as a c string
2502 const char* src = (const char*) (name()->as_C_string());
2503 const int src_length = (int)strlen(src);
2504
2505 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2506
2507 // Add L as type indicator
2508 int dest_index = 0;
2509 dest[dest_index++] = 'L';
2510
2511 // Add the actual class name
2512 for (int src_index = 0; src_index < src_length; ) {
2513 dest[dest_index++] = src[src_index++];
2514 }
2515
2516 // If we have a hash, append it
2517 for (int hash_index = 0; hash_index < hash_len; ) {
2518 dest[dest_index++] = hash_buf[hash_index++];
2519 }
2520
2521 // Add the semicolon and the NULL
2522 dest[dest_index++] = ';';
2523 dest[dest_index] = '\0';
2524 return dest;
2525 }
2526
2527 // different verisons of is_same_class_package
2528 bool InstanceKlass::is_same_class_package(Klass* class2) {
2529 Klass* class1 = this;
2530 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2531 Symbol* classname1 = class1->name();
2532
2533 if (class2->oop_is_objArray()) {
2534 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2535 }
2536 oop classloader2;
2537 if (class2->oop_is_instance()) {
2538 classloader2 = InstanceKlass::cast(class2)->class_loader();
2539 } else {
2540 assert(class2->oop_is_typeArray(), "should be type array");
2541 classloader2 = NULL;
2542 }
2543 Symbol* classname2 = class2->name();
2544
2545 return InstanceKlass::is_same_class_package(classloader1, classname1,
2546 classloader2, classname2);
2547 }
2548
2549 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2550 Klass* class1 = this;
2551 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2552 Symbol* classname1 = class1->name();
2553
2554 return InstanceKlass::is_same_class_package(classloader1, classname1,
2555 classloader2, classname2);
2556 }
2557
2558 // return true if two classes are in the same package, classloader
2559 // and classname information is enough to determine a class's package
2560 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2561 oop class_loader2, Symbol* class_name2) {
2562 if (class_loader1 != class_loader2) {
2563 return false;
2564 } else if (class_name1 == class_name2) {
2565 return true; // skip painful bytewise comparison
2566 } else {
2567 ResourceMark rm;
2568
2569 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2570 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2571 // Otherwise, we just compare jbyte values between the strings.
2572 const jbyte *name1 = class_name1->base();
2573 const jbyte *name2 = class_name2->base();
2574
2575 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2576 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2577
2578 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2579 // One of the two doesn't have a package. Only return true
2580 // if the other one also doesn't have a package.
2581 return last_slash1 == last_slash2;
2582 } else {
2583 // Skip over '['s
2584 if (*name1 == '[') {
2585 do {
2586 name1++;
2587 } while (*name1 == '[');
2588 if (*name1 != 'L') {
2589 // Something is terribly wrong. Shouldn't be here.
2590 return false;
2591 }
2592 }
2593 if (*name2 == '[') {
2594 do {
2595 name2++;
2596 } while (*name2 == '[');
2597 if (*name2 != 'L') {
2598 // Something is terribly wrong. Shouldn't be here.
2599 return false;
2600 }
2601 }
2602
2603 // Check that package part is identical
2604 int length1 = last_slash1 - name1;
2605 int length2 = last_slash2 - name2;
2606
2607 return UTF8::equal(name1, length1, name2, length2);
2608 }
2609 }
2610 }
2611
2612 // Returns true iff super_method can be overridden by a method in targetclassname
2613 // See JSL 3rd edition 8.4.6.1
2614 // Assumes name-signature match
2615 // "this" is InstanceKlass of super_method which must exist
2616 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2617 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2618 // Private methods can not be overridden
2619 if (super_method->is_private()) {
2620 return false;
2621 }
2622 // If super method is accessible, then override
2623 if ((super_method->is_protected()) ||
2624 (super_method->is_public())) {
2625 return true;
2626 }
2627 // Package-private methods are not inherited outside of package
2628 assert(super_method->is_package_private(), "must be package private");
2629 return(is_same_class_package(targetclassloader(), targetclassname));
2630 }
2631
2632 /* defined for now in jvm.cpp, for historical reasons *--
2633 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2634 Symbol*& simple_name_result, TRAPS) {
2635 ...
2636 }
2637 */
2638
2639 // tell if two classes have the same enclosing class (at package level)
2640 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2641 Klass* class2_oop, TRAPS) {
2642 if (class2_oop == class1()) return true;
2643 if (!class2_oop->oop_is_instance()) return false;
2644 instanceKlassHandle class2(THREAD, class2_oop);
2645
2646 // must be in same package before we try anything else
2647 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2648 return false;
2649
2650 // As long as there is an outer1.getEnclosingClass,
2651 // shift the search outward.
2652 instanceKlassHandle outer1 = class1;
2653 for (;;) {
2654 // As we walk along, look for equalities between outer1 and class2.
2655 // Eventually, the walks will terminate as outer1 stops
2656 // at the top-level class around the original class.
2657 bool ignore_inner_is_member;
2658 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2659 CHECK_false);
2660 if (next == NULL) break;
2661 if (next == class2()) return true;
2662 outer1 = instanceKlassHandle(THREAD, next);
2663 }
2664
2665 // Now do the same for class2.
2666 instanceKlassHandle outer2 = class2;
2667 for (;;) {
2668 bool ignore_inner_is_member;
2669 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2670 CHECK_false);
2671 if (next == NULL) break;
2672 // Might as well check the new outer against all available values.
2673 if (next == class1()) return true;
2674 if (next == outer1()) return true;
2675 outer2 = instanceKlassHandle(THREAD, next);
2676 }
2677
2678 // If by this point we have not found an equality between the
2679 // two classes, we know they are in separate package members.
2680 return false;
2681 }
2682
2683
2684 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2685 jint access = access_flags().as_int();
2686
2687 // But check if it happens to be member class.
2688 instanceKlassHandle ik(THREAD, this);
2689 InnerClassesIterator iter(ik);
2690 for (; !iter.done(); iter.next()) {
2691 int ioff = iter.inner_class_info_index();
2692 // Inner class attribute can be zero, skip it.
2693 // Strange but true: JVM spec. allows null inner class refs.
2694 if (ioff == 0) continue;
2695
2696 // only look at classes that are already loaded
2697 // since we are looking for the flags for our self.
2698 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2699 if ((ik->name() == inner_name)) {
2700 // This is really a member class.
2701 access = iter.inner_access_flags();
2702 break;
2703 }
2704 }
2705 // Remember to strip ACC_SUPER bit
2706 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2707 }
2708
2709 jint InstanceKlass::jvmti_class_status() const {
2710 jint result = 0;
2711
2712 if (is_linked()) {
2713 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2714 }
2715
2716 if (is_initialized()) {
2717 assert(is_linked(), "Class status is not consistent");
2718 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2719 }
2720 if (is_in_error_state()) {
2721 result |= JVMTI_CLASS_STATUS_ERROR;
2722 }
2723 return result;
2724 }
2725
2726 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2727 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2728 int method_table_offset_in_words = ioe->offset()/wordSize;
2729 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2730 / itableOffsetEntry::size();
2731
2732 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2733 // If the interface isn't implemented by the receiver class,
2734 // the VM should throw IncompatibleClassChangeError.
2735 if (cnt >= nof_interfaces) {
2736 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2737 }
2738
2739 Klass* ik = ioe->interface_klass();
2740 if (ik == holder) break;
2741 }
2742
2743 itableMethodEntry* ime = ioe->first_method_entry(this);
2744 Method* m = ime[index].method();
2745 if (m == NULL) {
2746 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2747 }
2748 return m;
2749 }
2750
2751
2752 #if INCLUDE_JVMTI
2753 // update default_methods for redefineclasses for methods that are
2754 // not yet in the vtable due to concurrent subclass define and superinterface
2755 // redefinition
2756 // Note: those in the vtable, should have been updated via adjust_method_entries
2757 void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods,
2758 int methods_length, bool* trace_name_printed) {
2759 // search the default_methods for uses of either obsolete or EMCP methods
2760 if (default_methods() != NULL) {
2761 for (int j = 0; j < methods_length; j++) {
2762 Method* old_method = old_methods[j];
2763 Method* new_method = new_methods[j];
2764
2765 for (int index = 0; index < default_methods()->length(); index ++) {
2766 if (default_methods()->at(index) == old_method) {
2767 default_methods()->at_put(index, new_method);
2768 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2769 if (!(*trace_name_printed)) {
2770 // RC_TRACE_MESG macro has an embedded ResourceMark
2771 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2772 external_name(),
2773 old_method->method_holder()->external_name()));
2774 *trace_name_printed = true;
2775 }
2776 RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2777 new_method->name()->as_C_string(),
2778 new_method->signature()->as_C_string()));
2779 }
2780 }
2781 }
2782 }
2783 }
2784 }
2785 #endif // INCLUDE_JVMTI
2786
2787 // On-stack replacement stuff
2788 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2789 // only one compilation can be active
2790 NEEDS_CLEANUP
2791 // This is a short non-blocking critical region, so the no safepoint check is ok.
2792 OsrList_lock->lock_without_safepoint_check();
2793 assert(n->is_osr_method(), "wrong kind of nmethod");
2794 n->set_osr_link(osr_nmethods_head());
2795 set_osr_nmethods_head(n);
2796 // Raise the highest osr level if necessary
2797 if (TieredCompilation) {
2798 Method* m = n->method();
2799 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2800 }
2801 // Remember to unlock again
2802 OsrList_lock->unlock();
2803
2804 // Get rid of the osr methods for the same bci that have lower levels.
2805 if (TieredCompilation) {
2806 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2807 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2808 if (inv != NULL && inv->is_in_use()) {
2809 inv->make_not_entrant();
2810 }
2811 }
2812 }
2813 }
2814
2815
2816 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2817 // This is a short non-blocking critical region, so the no safepoint check is ok.
2818 OsrList_lock->lock_without_safepoint_check();
2819 assert(n->is_osr_method(), "wrong kind of nmethod");
2820 nmethod* last = NULL;
2821 nmethod* cur = osr_nmethods_head();
2822 int max_level = CompLevel_none; // Find the max comp level excluding n
2823 Method* m = n->method();
2824 // Search for match
2825 while(cur != NULL && cur != n) {
2826 if (TieredCompilation && m == cur->method()) {
2827 // Find max level before n
2828 max_level = MAX2(max_level, cur->comp_level());
2829 }
2830 last = cur;
2831 cur = cur->osr_link();
2832 }
2833 nmethod* next = NULL;
2834 if (cur == n) {
2835 next = cur->osr_link();
2836 if (last == NULL) {
2837 // Remove first element
2838 set_osr_nmethods_head(next);
2839 } else {
2840 last->set_osr_link(next);
2841 }
2842 }
2843 n->set_osr_link(NULL);
2844 if (TieredCompilation) {
2845 cur = next;
2846 while (cur != NULL) {
2847 // Find max level after n
2848 if (m == cur->method()) {
2849 max_level = MAX2(max_level, cur->comp_level());
2850 }
2851 cur = cur->osr_link();
2852 }
2853 m->set_highest_osr_comp_level(max_level);
2854 }
2855 // Remember to unlock again
2856 OsrList_lock->unlock();
2857 }
2858
2859 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2860 // This is a short non-blocking critical region, so the no safepoint check is ok.
2861 OsrList_lock->lock_without_safepoint_check();
2862 nmethod* osr = osr_nmethods_head();
2863 nmethod* best = NULL;
2864 while (osr != NULL) {
2865 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2866 // There can be a time when a c1 osr method exists but we are waiting
2867 // for a c2 version. When c2 completes its osr nmethod we will trash
2868 // the c1 version and only be able to find the c2 version. However
2869 // while we overflow in the c1 code at back branches we don't want to
2870 // try and switch to the same code as we are already running
2871
2872 if (osr->method() == m &&
2873 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2874 if (match_level) {
2875 if (osr->comp_level() == comp_level) {
2876 // Found a match - return it.
2877 OsrList_lock->unlock();
2878 return osr;
2879 }
2880 } else {
2881 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2882 if (osr->comp_level() == CompLevel_highest_tier) {
2883 // Found the best possible - return it.
2884 OsrList_lock->unlock();
2885 return osr;
2886 }
2887 best = osr;
2888 }
2889 }
2890 }
2891 osr = osr->osr_link();
2892 }
2893 OsrList_lock->unlock();
2894 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2895 return best;
2896 }
2897 return NULL;
2898 }
2899
2900 void InstanceKlass::add_member_name(int index, Handle mem_name) {
2901 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2902 MutexLocker ml(MemberNameTable_lock);
2903 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2904 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2905
2906 if (_member_names == NULL) {
2907 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2908 }
2909 _member_names->add_member_name(index, mem_name_wref);
2910 }
2911
2912 oop InstanceKlass::get_member_name(int index) {
2913 MutexLocker ml(MemberNameTable_lock);
2914 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2915 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2916
2917 if (_member_names == NULL) {
2918 return NULL;
2919 }
2920 oop mem_name =_member_names->get_member_name(index);
2921 return mem_name;
2922 }
2923
2924 // -----------------------------------------------------------------------------------------------------
2925 // Printing
2926
2927 #ifndef PRODUCT
2928
2929 #define BULLET " - "
2930
2931 static const char* state_names[] = {
2932 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2933 };
2934
2935 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2936 for (int i = 0; i < len; i++) {
2937 intptr_t e = start[i];
2938 st->print("%d : " INTPTR_FORMAT, i, e);
2939 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2940 st->print(" ");
2941 ((Metadata*)e)->print_value_on(st);
2942 }
2943 st->cr();
2944 }
2945 }
2946
2947 void InstanceKlass::print_on(outputStream* st) const {
2948 assert(is_klass(), "must be klass");
2949 Klass::print_on(st);
2950
2951 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2952 st->print(BULLET"klass size: %d", size()); st->cr();
2953 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2954 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2955 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2956 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2957 st->print(BULLET"sub: ");
2958 Klass* sub = subklass();
2959 int n;
2960 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2961 if (n < MaxSubklassPrintSize) {
2962 sub->print_value_on(st);
2963 st->print(" ");
2964 }
2965 }
2966 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2967 st->cr();
2968
2969 if (is_interface()) {
2970 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2971 if (nof_implementors() == 1) {
2972 st->print_cr(BULLET"implementor: ");
2973 st->print(" ");
2974 implementor()->print_value_on(st);
2975 st->cr();
2976 }
2977 }
2978
2979 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2980 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2981 if (Verbose || WizardMode) {
2982 Array<Method*>* method_array = methods();
2983 for (int i = 0; i < method_array->length(); i++) {
2984 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2985 }
2986 }
2987 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2988 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2989 if (Verbose && default_methods() != NULL) {
2990 Array<Method*>* method_array = default_methods();
2991 for (int i = 0; i < method_array->length(); i++) {
2992 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2993 }
2994 }
2995 if (default_vtable_indices() != NULL) {
2996 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2997 }
2998 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2999 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3000 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3001 if (class_loader_data() != NULL) {
3002 st->print(BULLET"class loader data: ");
3003 class_loader_data()->print_value_on(st);
3004 st->cr();
3005 }
3006 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3007 if (source_file_name() != NULL) {
3008 st->print(BULLET"source file: ");
3009 source_file_name()->print_value_on(st);
3010 st->cr();
3011 }
3012 if (source_debug_extension() != NULL) {
3013 st->print(BULLET"source debug extension: ");
3014 st->print("%s", source_debug_extension());
3015 st->cr();
3016 }
3017 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3018 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3019 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3020 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3021 {
3022 bool have_pv = false;
3023 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
3024 for (PreviousVersionNode * pv_node = pvw.next_previous_version();
3025 pv_node != NULL; pv_node = pvw.next_previous_version()) {
3026 if (!have_pv)
3027 st->print(BULLET"previous version: ");
3028 have_pv = true;
3029 pv_node->prev_constant_pool()->print_value_on(st);
3030 }
3031 if (have_pv) st->cr();
3032 } // pvw is cleaned up
3033
3034 if (generic_signature() != NULL) {
3035 st->print(BULLET"generic signature: ");
3036 generic_signature()->print_value_on(st);
3037 st->cr();
3038 }
3039 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3040 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3041 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
3042 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3043 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
3044 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3045 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3046 FieldPrinter print_static_field(st);
3047 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3048 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3049 FieldPrinter print_nonstatic_field(st);
3050 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
3051
3052 st->print(BULLET"non-static oop maps: ");
3053 OopMapBlock* map = start_of_nonstatic_oop_maps();
3054 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3055 while (map < end_map) {
3056 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3057 map++;
3058 }
3059 st->cr();
3060 }
3061
3062 #endif //PRODUCT
3063
3064 void InstanceKlass::print_value_on(outputStream* st) const {
3065 assert(is_klass(), "must be klass");
3066 if (Verbose || WizardMode) access_flags().print_on(st);
3067 name()->print_value_on(st);
3068 }
3069
3070 #ifndef PRODUCT
3071
3072 void FieldPrinter::do_field(fieldDescriptor* fd) {
3073 _st->print(BULLET);
3074 if (_obj == NULL) {
3075 fd->print_on(_st);
3076 _st->cr();
3077 } else {
3078 fd->print_on_for(_st, _obj);
3079 _st->cr();
3080 }
3081 }
3082
3083
3084 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3085 Klass::oop_print_on(obj, st);
3086
3087 if (this == SystemDictionary::String_klass()) {
3088 typeArrayOop value = java_lang_String::value(obj);
3089 juint offset = java_lang_String::offset(obj);
3090 juint length = java_lang_String::length(obj);
3091 if (value != NULL &&
3092 value->is_typeArray() &&
3093 offset <= (juint) value->length() &&
3094 offset + length <= (juint) value->length()) {
3095 st->print(BULLET"string: ");
3096 java_lang_String::print(obj, st);
3097 st->cr();
3098 if (!WizardMode) return; // that is enough
3099 }
3100 }
3101
3102 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3103 FieldPrinter print_field(st, obj);
3104 do_nonstatic_fields(&print_field);
3105
3106 if (this == SystemDictionary::Class_klass()) {
3107 st->print(BULLET"signature: ");
3108 java_lang_Class::print_signature(obj, st);
3109 st->cr();
3110 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3111 st->print(BULLET"fake entry for mirror: ");
3112 mirrored_klass->print_value_on_maybe_null(st);
3113 st->cr();
3114 Klass* array_klass = java_lang_Class::array_klass(obj);
3115 st->print(BULLET"fake entry for array: ");
3116 array_klass->print_value_on_maybe_null(st);
3117 st->cr();
3118 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3119 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3120 Klass* real_klass = java_lang_Class::as_Klass(obj);
3121 if (real_klass != NULL && real_klass->oop_is_instance()) {
3122 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3123 }
3124 } else if (this == SystemDictionary::MethodType_klass()) {
3125 st->print(BULLET"signature: ");
3126 java_lang_invoke_MethodType::print_signature(obj, st);
3127 st->cr();
3128 }
3129 }
3130
3131 #endif //PRODUCT
3132
3133 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3134 st->print("a ");
3135 name()->print_value_on(st);
3136 obj->print_address_on(st);
3137 if (this == SystemDictionary::String_klass()
3138 && java_lang_String::value(obj) != NULL) {
3139 ResourceMark rm;
3140 int len = java_lang_String::length(obj);
3141 int plen = (len < 24 ? len : 12);
3142 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3143 st->print(" = \"%s\"", str);
3144 if (len > plen)
3145 st->print("...[%d]", len);
3146 } else if (this == SystemDictionary::Class_klass()) {
3147 Klass* k = java_lang_Class::as_Klass(obj);
3148 st->print(" = ");
3149 if (k != NULL) {
3150 k->print_value_on(st);
3151 } else {
3152 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3153 st->print("%s", tname ? tname : "type?");
3154 }
3155 } else if (this == SystemDictionary::MethodType_klass()) {
3156 st->print(" = ");
3157 java_lang_invoke_MethodType::print_signature(obj, st);
3158 } else if (java_lang_boxing_object::is_instance(obj)) {
3159 st->print(" = ");
3160 java_lang_boxing_object::print(obj, st);
3161 } else if (this == SystemDictionary::LambdaForm_klass()) {
3162 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3163 if (vmentry != NULL) {
3164 st->print(" => ");
3165 vmentry->print_value_on(st);
3166 }
3167 } else if (this == SystemDictionary::MemberName_klass()) {
3168 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3169 if (vmtarget != NULL) {
3170 st->print(" = ");
3171 vmtarget->print_value_on(st);
3172 } else {
3173 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3174 st->print(".");
3175 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3176 }
3177 }
3178 }
3179
3180 const char* InstanceKlass::internal_name() const {
3181 return external_name();
3182 }
3183
3184 #if INCLUDE_SERVICES
3185 // Size Statistics
3186 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3187 Klass::collect_statistics(sz);
3188
3189 sz->_inst_size = HeapWordSize * size_helper();
3190 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
3191 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
3192 sz->_nonstatic_oopmap_bytes = HeapWordSize *
3193 ((is_interface() || is_anonymous()) ?
3194 align_object_offset(nonstatic_oop_map_size()) :
3195 nonstatic_oop_map_size());
3196
3197 int n = 0;
3198 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3199 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3200 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3201 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3202 n += (sz->_fields_bytes = sz->count_array(fields()));
3203 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3204 sz->_ro_bytes += n;
3205
3206 const ConstantPool* cp = constants();
3207 if (cp) {
3208 cp->collect_statistics(sz);
3209 }
3210
3211 const Annotations* anno = annotations();
3212 if (anno) {
3213 anno->collect_statistics(sz);
3214 }
3215
3216 const Array<Method*>* methods_array = methods();
3217 if (methods()) {
3218 for (int i = 0; i < methods_array->length(); i++) {
3219 Method* method = methods_array->at(i);
3220 if (method) {
3221 sz->_method_count ++;
3222 method->collect_statistics(sz);
3223 }
3224 }
3225 }
3226 }
3227 #endif // INCLUDE_SERVICES
3228
3229 // Verification
3230
3231 class VerifyFieldClosure: public OopClosure {
3232 protected:
3233 template <class T> void do_oop_work(T* p) {
3234 oop obj = oopDesc::load_decode_heap_oop(p);
3235 if (!obj->is_oop_or_null()) {
3236 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
3237 Universe::print();
3238 guarantee(false, "boom");
3239 }
3240 }
3241 public:
3242 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3243 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3244 };
3245
3246 void InstanceKlass::verify_on(outputStream* st) {
3247 #ifndef PRODUCT
3248 // Avoid redundant verifies, this really should be in product.
3249 if (_verify_count == Universe::verify_count()) return;
3250 _verify_count = Universe::verify_count();
3251 #endif
3252
3253 // Verify Klass
3254 Klass::verify_on(st);
3255
3256 // Verify that klass is present in ClassLoaderData
3257 guarantee(class_loader_data()->contains_klass(this),
3258 "this class isn't found in class loader data");
3259
3260 // Verify vtables
3261 if (is_linked()) {
3262 ResourceMark rm;
3263 // $$$ This used to be done only for m/s collections. Doing it
3264 // always seemed a valid generalization. (DLD -- 6/00)
3265 vtable()->verify(st);
3266 }
3267
3268 // Verify first subklass
3269 if (subklass() != NULL) {
3270 guarantee(subklass()->is_klass(), "should be klass");
3271 }
3272
3273 // Verify siblings
3274 Klass* super = this->super();
3275 Klass* sib = next_sibling();
3276 if (sib != NULL) {
3277 if (sib == this) {
3278 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3279 }
3280
3281 guarantee(sib->is_klass(), "should be klass");
3282 guarantee(sib->super() == super, "siblings should have same superklass");
3283 }
3284
3285 // Verify implementor fields
3286 Klass* im = implementor();
3287 if (im != NULL) {
3288 guarantee(is_interface(), "only interfaces should have implementor set");
3289 guarantee(im->is_klass(), "should be klass");
3290 guarantee(!im->is_interface() || im == this,
3291 "implementors cannot be interfaces");
3292 }
3293
3294 // Verify local interfaces
3295 if (local_interfaces()) {
3296 Array<Klass*>* local_interfaces = this->local_interfaces();
3297 for (int j = 0; j < local_interfaces->length(); j++) {
3298 Klass* e = local_interfaces->at(j);
3299 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3300 }
3301 }
3302
3303 // Verify transitive interfaces
3304 if (transitive_interfaces() != NULL) {
3305 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3306 for (int j = 0; j < transitive_interfaces->length(); j++) {
3307 Klass* e = transitive_interfaces->at(j);
3308 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3309 }
3310 }
3311
3312 // Verify methods
3313 if (methods() != NULL) {
3314 Array<Method*>* methods = this->methods();
3315 for (int j = 0; j < methods->length(); j++) {
3316 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3317 }
3318 for (int j = 0; j < methods->length() - 1; j++) {
3319 Method* m1 = methods->at(j);
3320 Method* m2 = methods->at(j + 1);
3321 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3322 }
3323 }
3324
3325 // Verify method ordering
3326 if (method_ordering() != NULL) {
3327 Array<int>* method_ordering = this->method_ordering();
3328 int length = method_ordering->length();
3329 if (JvmtiExport::can_maintain_original_method_order() ||
3330 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3331 guarantee(length == methods()->length(), "invalid method ordering length");
3332 jlong sum = 0;
3333 for (int j = 0; j < length; j++) {
3334 int original_index = method_ordering->at(j);
3335 guarantee(original_index >= 0, "invalid method ordering index");
3336 guarantee(original_index < length, "invalid method ordering index");
3337 sum += original_index;
3338 }
3339 // Verify sum of indices 0,1,...,length-1
3340 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3341 } else {
3342 guarantee(length == 0, "invalid method ordering length");
3343 }
3344 }
3345
3346 // Verify default methods
3347 if (default_methods() != NULL) {
3348 Array<Method*>* methods = this->default_methods();
3349 for (int j = 0; j < methods->length(); j++) {
3350 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3351 }
3352 for (int j = 0; j < methods->length() - 1; j++) {
3353 Method* m1 = methods->at(j);
3354 Method* m2 = methods->at(j + 1);
3355 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3356 }
3357 }
3358
3359 // Verify JNI static field identifiers
3360 if (jni_ids() != NULL) {
3361 jni_ids()->verify(this);
3362 }
3363
3364 // Verify other fields
3365 if (array_klasses() != NULL) {
3366 guarantee(array_klasses()->is_klass(), "should be klass");
3367 }
3368 if (constants() != NULL) {
3369 guarantee(constants()->is_constantPool(), "should be constant pool");
3370 }
3371 const Klass* host = host_klass();
3372 if (host != NULL) {
3373 guarantee(host->is_klass(), "should be klass");
3374 }
3375 }
3376
3377 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3378 Klass::oop_verify_on(obj, st);
3379 VerifyFieldClosure blk;
3380 obj->oop_iterate_no_header(&blk);
3381 }
3382
3383
3384 // JNIid class for jfieldIDs only
3385 // Note to reviewers:
3386 // These JNI functions are just moved over to column 1 and not changed
3387 // in the compressed oops workspace.
3388 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3389 _holder = holder;
3390 _offset = offset;
3391 _next = next;
3392 debug_only(_is_static_field_id = false;)
3393 }
3394
3395
3396 JNIid* JNIid::find(int offset) {
3397 JNIid* current = this;
3398 while (current != NULL) {
3399 if (current->offset() == offset) return current;
3400 current = current->next();
3401 }
3402 return NULL;
3403 }
3404
3405 void JNIid::deallocate(JNIid* current) {
3406 while (current != NULL) {
3407 JNIid* next = current->next();
3408 delete current;
3409 current = next;
3410 }
3411 }
3412
3413
3414 void JNIid::verify(Klass* holder) {
3415 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3416 int end_field_offset;
3417 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3418
3419 JNIid* current = this;
3420 while (current != NULL) {
3421 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3422 #ifdef ASSERT
3423 int o = current->offset();
3424 if (current->is_static_field_id()) {
3425 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3426 }
3427 #endif
3428 current = current->next();
3429 }
3430 }
3431
3432
3433 #ifdef ASSERT
3434 void InstanceKlass::set_init_state(ClassState state) {
3435 bool good_state = is_shared() ? (_init_state <= state)
3436 : (_init_state < state);
3437 assert(good_state || state == allocated, "illegal state transition");
3438 _init_state = (u1)state;
3439 }
3440 #endif
3441
3442
3443 // RedefineClasses() support for previous versions:
3444
3445 // Purge previous versions
3446 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3447 if (ik->previous_versions() != NULL) {
3448 // This klass has previous versions so see what we can cleanup
3449 // while it is safe to do so.
3450
3451 int deleted_count = 0; // leave debugging breadcrumbs
3452 int live_count = 0;
3453 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3454 ClassLoaderData::the_null_class_loader_data() :
3455 ik->class_loader_data();
3456
3457 // RC_TRACE macro has an embedded ResourceMark
3458 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3459 ik->external_name(), ik->previous_versions()->length()));
3460
3461 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3462 // check the previous versions array
3463 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3464 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3465 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3466
3467 ConstantPool* pvcp = cp_ref;
3468 if (!pvcp->on_stack()) {
3469 // If the constant pool isn't on stack, none of the methods
3470 // are executing. Delete all the methods, the constant pool and
3471 // and this previous version node.
3472 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3473 if (method_refs != NULL) {
3474 for (int j = method_refs->length() - 1; j >= 0; j--) {
3475 Method* method = method_refs->at(j);
3476 assert(method != NULL, "method ref was unexpectedly cleared");
3477 method_refs->remove_at(j);
3478 // method will be freed with associated class.
3479 }
3480 }
3481 // Remove the constant pool
3482 delete pv_node;
3483 // Since we are traversing the array backwards, we don't have to
3484 // do anything special with the index.
3485 ik->previous_versions()->remove_at(i);
3486 deleted_count++;
3487 continue;
3488 } else {
3489 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3490 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3491 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3492 live_count++;
3493 }
3494
3495 // At least one method is live in this previous version, clean out
3496 // the others or mark them as obsolete.
3497 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3498 if (method_refs != NULL) {
3499 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3500 method_refs->length()));
3501 for (int j = method_refs->length() - 1; j >= 0; j--) {
3502 Method* method = method_refs->at(j);
3503 assert(method != NULL, "method ref was unexpectedly cleared");
3504
3505 // Remove the emcp method if it's not executing
3506 // If it's been made obsolete by a redefinition of a non-emcp
3507 // method, mark it as obsolete but leave it to clean up later.
3508 if (!method->on_stack()) {
3509 method_refs->remove_at(j);
3510 } else if (emcp_method_count == 0) {
3511 method->set_is_obsolete();
3512 } else {
3513 // RC_TRACE macro has an embedded ResourceMark
3514 RC_TRACE(0x00000200,
3515 ("purge: %s(%s): prev method @%d in version @%d is alive",
3516 method->name()->as_C_string(),
3517 method->signature()->as_C_string(), j, i));
3518 if (method->method_data() != NULL) {
3519 // Clean out any weak method links
3520 method->method_data()->clean_weak_method_links();
3521 }
3522 }
3523 }
3524 }
3525 }
3526 assert(ik->previous_versions()->length() == live_count, "sanity check");
3527 RC_TRACE(0x00000200,
3528 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3529 deleted_count));
3530 }
3531
3532 Array<Method*>* methods = ik->methods();
3533 int num_methods = methods->length();
3534 for (int index2 = 0; index2 < num_methods; ++index2) {
3535 if (methods->at(index2)->method_data() != NULL) {
3536 methods->at(index2)->method_data()->clean_weak_method_links();
3537 }
3538 }
3539 }
3540
3541 // External interface for use during class unloading.
3542 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3543 // Call with >0 emcp methods since they are not currently being redefined.
3544 purge_previous_versions_internal(ik, 1);
3545 }
3546
3547
3548 // Potentially add an information node that contains pointers to the
3549 // interesting parts of the previous version of the_class.
3550 // This is also where we clean out any unused references.
3551 // Note that while we delete nodes from the _previous_versions
3552 // array, we never delete the array itself until the klass is
3553 // unloaded. The has_been_redefined() query depends on that fact.
3554 //
3555 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3556 BitMap* emcp_methods, int emcp_method_count) {
3557 assert(Thread::current()->is_VM_thread(),
3558 "only VMThread can add previous versions");
3559
3560 if (_previous_versions == NULL) {
3561 // This is the first previous version so make some space.
3562 // Start with 2 elements under the assumption that the class
3563 // won't be redefined much.
3564 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3565 GrowableArray<PreviousVersionNode *>(2, true);
3566 }
3567
3568 ConstantPool* cp_ref = ikh->constants();
3569
3570 // RC_TRACE macro has an embedded ResourceMark
3571 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3572 "on_stack=%d",
3573 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3574 cp_ref->on_stack()));
3575
3576 // If the constant pool for this previous version of the class
3577 // is not marked as being on the stack, then none of the methods
3578 // in this previous version of the class are on the stack so
3579 // we don't need to create a new PreviousVersionNode. However,
3580 // we still need to examine older previous versions below.
3581 Array<Method*>* old_methods = ikh->methods();
3582
3583 if (cp_ref->on_stack()) {
3584 PreviousVersionNode * pv_node = NULL;
3585 if (emcp_method_count == 0) {
3586 // non-shared ConstantPool gets a reference
3587 pv_node = new PreviousVersionNode(cp_ref, NULL);
3588 RC_TRACE(0x00000400,
3589 ("add: all methods are obsolete; flushing any EMCP refs"));
3590 } else {
3591 int local_count = 0;
3592 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3593 GrowableArray<Method*>(emcp_method_count, true);
3594 for (int i = 0; i < old_methods->length(); i++) {
3595 if (emcp_methods->at(i)) {
3596 // this old method is EMCP. Save it only if it's on the stack
3597 Method* old_method = old_methods->at(i);
3598 if (old_method->on_stack()) {
3599 method_refs->append(old_method);
3600 }
3601 if (++local_count >= emcp_method_count) {
3602 // no more EMCP methods so bail out now
3603 break;
3604 }
3605 }
3606 }
3607 // non-shared ConstantPool gets a reference
3608 pv_node = new PreviousVersionNode(cp_ref, method_refs);
3609 }
3610 // append new previous version.
3611 _previous_versions->append(pv_node);
3612 }
3613
3614 // Since the caller is the VMThread and we are at a safepoint, this
3615 // is a good time to clear out unused references.
3616
3617 RC_TRACE(0x00000400, ("add: previous version length=%d",
3618 _previous_versions->length()));
3619
3620 // Purge previous versions not executing on the stack
3621 purge_previous_versions_internal(this, emcp_method_count);
3622
3623 int obsolete_method_count = old_methods->length() - emcp_method_count;
3624
3625 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3626 _previous_versions->length() > 0) {
3627 // We have a mix of obsolete and EMCP methods so we have to
3628 // clear out any matching EMCP method entries the hard way.
3629 int local_count = 0;
3630 for (int i = 0; i < old_methods->length(); i++) {
3631 if (!emcp_methods->at(i)) {
3632 // only obsolete methods are interesting
3633 Method* old_method = old_methods->at(i);
3634 Symbol* m_name = old_method->name();
3635 Symbol* m_signature = old_method->signature();
3636
3637 // we might not have added the last entry
3638 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3639 // check the previous versions array for non executing obsolete methods
3640 PreviousVersionNode * pv_node = _previous_versions->at(j);
3641
3642 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3643 if (method_refs == NULL) {
3644 // We have run into a PreviousVersion generation where
3645 // all methods were made obsolete during that generation's
3646 // RedefineClasses() operation. At the time of that
3647 // operation, all EMCP methods were flushed so we don't
3648 // have to go back any further.
3649 //
3650 // A NULL method_refs is different than an empty method_refs.
3651 // We cannot infer any optimizations about older generations
3652 // from an empty method_refs for the current generation.
3653 break;
3654 }
3655
3656 for (int k = method_refs->length() - 1; k >= 0; k--) {
3657 Method* method = method_refs->at(k);
3658
3659 if (!method->is_obsolete() &&
3660 method->name() == m_name &&
3661 method->signature() == m_signature) {
3662 // The current RedefineClasses() call has made all EMCP
3663 // versions of this method obsolete so mark it as obsolete
3664 // and remove the reference.
3665 RC_TRACE(0x00000400,
3666 ("add: %s(%s): flush obsolete method @%d in version @%d",
3667 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3668
3669 method->set_is_obsolete();
3670 // Leave obsolete methods on the previous version list to
3671 // clean up later.
3672 break;
3673 }
3674 }
3675
3676 // The previous loop may not find a matching EMCP method, but
3677 // that doesn't mean that we can optimize and not go any
3678 // further back in the PreviousVersion generations. The EMCP
3679 // method for this generation could have already been deleted,
3680 // but there still may be an older EMCP method that has not
3681 // been deleted.
3682 }
3683
3684 if (++local_count >= obsolete_method_count) {
3685 // no more obsolete methods so bail out now
3686 break;
3687 }
3688 }
3689 }
3690 }
3691 } // end add_previous_version()
3692
3693
3694 // Determine if InstanceKlass has a previous version.
3695 bool InstanceKlass::has_previous_version() const {
3696 return (_previous_versions != NULL && _previous_versions->length() > 0);
3697 } // end has_previous_version()
3698
3699
3700 Method* InstanceKlass::method_with_idnum(int idnum) {
3701 Method* m = NULL;
3702 if (idnum < methods()->length()) {
3703 m = methods()->at(idnum);
3704 }
3705 if (m == NULL || m->method_idnum() != idnum) {
3706 for (int index = 0; index < methods()->length(); ++index) {
3707 m = methods()->at(index);
3708 if (m->method_idnum() == idnum) {
3709 return m;
3710 }
3711 }
3712 // None found, return null for the caller to handle.
3713 return NULL;
3714 }
3715 return m;
3716 }
3717
3718 jint InstanceKlass::get_cached_class_file_len() {
3719 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3720 }
3721
3722 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3723 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3724 }
3725
3726
3727 // Construct a PreviousVersionNode entry for the array hung off
3728 // the InstanceKlass.
3729 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3730 GrowableArray<Method*>* prev_EMCP_methods) {
3731
3732 _prev_constant_pool = prev_constant_pool;
3733 _prev_EMCP_methods = prev_EMCP_methods;
3734 }
3735
3736
3737 // Destroy a PreviousVersionNode
3738 PreviousVersionNode::~PreviousVersionNode() {
3739 if (_prev_constant_pool != NULL) {
3740 _prev_constant_pool = NULL;
3741 }
3742
3743 if (_prev_EMCP_methods != NULL) {
3744 delete _prev_EMCP_methods;
3745 }
3746 }
3747
3748 // Construct a helper for walking the previous versions array
3749 PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) {
3750 _thread = thread;
3751 _previous_versions = ik->previous_versions();
3752 _current_index = 0;
3753 _current_p = NULL;
3754 _current_constant_pool_handle = constantPoolHandle(thread, ik->constants());
3755 }
3756
3757
3758 // Return the interesting information for the next previous version
3759 // of the klass. Returns NULL if there are no more previous versions.
3760 PreviousVersionNode* PreviousVersionWalker::next_previous_version() {
3761 if (_previous_versions == NULL) {
3762 // no previous versions so nothing to return
3763 return NULL;
3764 }
3765
3766 _current_p = NULL; // reset to NULL
3767 _current_constant_pool_handle = NULL;
3768
3769 int length = _previous_versions->length();
3770
3771 while (_current_index < length) {
3772 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3773
3774 // Save a handle to the constant pool for this previous version,
3775 // which keeps all the methods from being deallocated.
3776 _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool());
3777 _current_p = pv_node;
3778 return pv_node;
3779 }
3780
3781 return NULL;
3782 } // end next_previous_version()