Fri, 24 Feb 2017 06:48:48 -0800
8162795: [REDO] MemberNameTable doesn't purge stale entries
Summary: Re-application of the change in JDK-8152271.
Reviewed-by: coleenp, sspitsyn
1 /*
2 * Copyright (c) 1997, 2016, 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 */
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/systemDictionaryShared.hpp"
29 #include "classfile/verifier.hpp"
30 #include "classfile/vmSymbols.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "gc_implementation/shared/markSweep.inline.hpp"
33 #include "gc_interface/collectedHeap.inline.hpp"
34 #include "interpreter/oopMapCache.hpp"
35 #include "interpreter/rewriter.hpp"
36 #include "jvmtifiles/jvmti.h"
37 #include "memory/genOopClosures.inline.hpp"
38 #include "memory/heapInspection.hpp"
39 #include "memory/iterator.inline.hpp"
40 #include "memory/metadataFactory.hpp"
41 #include "memory/oopFactory.hpp"
42 #include "oops/fieldStreams.hpp"
43 #include "oops/instanceClassLoaderKlass.hpp"
44 #include "oops/instanceKlass.hpp"
45 #include "oops/instanceMirrorKlass.hpp"
46 #include "oops/instanceOop.hpp"
47 #include "oops/klass.inline.hpp"
48 #include "oops/method.hpp"
49 #include "oops/oop.inline.hpp"
50 #include "oops/symbol.hpp"
51 #include "prims/jvmtiExport.hpp"
52 #include "prims/jvmtiRedefineClassesTrace.hpp"
53 #include "prims/jvmtiRedefineClasses.hpp"
54 #include "prims/jvmtiThreadState.hpp"
55 #include "prims/methodComparator.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/heapRegionManager.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
82 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
84 #ifdef DTRACE_ENABLED
86 #ifndef USDT2
88 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
89 char*, intptr_t, oop, intptr_t);
90 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
91 char*, intptr_t, oop, intptr_t, int);
92 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
93 char*, intptr_t, oop, intptr_t, int);
94 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
95 char*, intptr_t, oop, intptr_t, int);
96 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
97 char*, intptr_t, oop, intptr_t, int);
98 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
99 char*, intptr_t, oop, intptr_t, int);
100 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
101 char*, intptr_t, oop, intptr_t, int);
102 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
103 char*, intptr_t, oop, intptr_t, int);
105 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
106 { \
107 char* data = NULL; \
108 int len = 0; \
109 Symbol* name = (clss)->name(); \
110 if (name != NULL) { \
111 data = (char*)name->bytes(); \
112 len = name->utf8_length(); \
113 } \
114 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \
115 data, len, (void *)(clss)->class_loader(), thread_type); \
116 }
118 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
119 { \
120 char* data = NULL; \
121 int len = 0; \
122 Symbol* name = (clss)->name(); \
123 if (name != NULL) { \
124 data = (char*)name->bytes(); \
125 len = name->utf8_length(); \
126 } \
127 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \
128 data, len, (void *)(clss)->class_loader(), thread_type, wait); \
129 }
130 #else /* USDT2 */
132 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
133 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
134 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
135 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
136 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
137 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
138 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
139 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
140 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
141 { \
142 char* data = NULL; \
143 int len = 0; \
144 Symbol* name = (clss)->name(); \
145 if (name != NULL) { \
146 data = (char*)name->bytes(); \
147 len = name->utf8_length(); \
148 } \
149 HOTSPOT_CLASS_INITIALIZATION_##type( \
150 data, len, (clss)->class_loader(), thread_type); \
151 }
153 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
154 { \
155 char* data = NULL; \
156 int len = 0; \
157 Symbol* name = (clss)->name(); \
158 if (name != NULL) { \
159 data = (char*)name->bytes(); \
160 len = name->utf8_length(); \
161 } \
162 HOTSPOT_CLASS_INITIALIZATION_##type( \
163 data, len, (clss)->class_loader(), thread_type, wait); \
164 }
165 #endif /* USDT2 */
167 #else // ndef DTRACE_ENABLED
169 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
170 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
172 #endif // ndef DTRACE_ENABLED
174 volatile int InstanceKlass::_total_instanceKlass_count = 0;
176 InstanceKlass* InstanceKlass::allocate_instance_klass(
177 ClassLoaderData* loader_data,
178 int vtable_len,
179 int itable_len,
180 int static_field_size,
181 int nonstatic_oop_map_size,
182 ReferenceType rt,
183 AccessFlags access_flags,
184 Symbol* name,
185 Klass* super_klass,
186 bool is_anonymous,
187 TRAPS) {
189 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
190 access_flags.is_interface(), is_anonymous);
192 // Allocation
193 InstanceKlass* ik;
194 if (rt == REF_NONE) {
195 if (name == vmSymbols::java_lang_Class()) {
196 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
197 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
198 access_flags, is_anonymous);
199 } else if (name == vmSymbols::java_lang_ClassLoader() ||
200 (SystemDictionary::ClassLoader_klass_loaded() &&
201 super_klass != NULL &&
202 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
203 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
204 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
205 access_flags, is_anonymous);
206 } else {
207 // normal class
208 ik = new (loader_data, size, THREAD) InstanceKlass(
209 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
210 access_flags, is_anonymous);
211 }
212 } else {
213 // reference klass
214 ik = new (loader_data, size, THREAD) InstanceRefKlass(
215 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
216 access_flags, is_anonymous);
217 }
219 // Check for pending exception before adding to the loader data and incrementing
220 // class count. Can get OOM here.
221 if (HAS_PENDING_EXCEPTION) {
222 return NULL;
223 }
225 // Add all classes to our internal class loader list here,
226 // including classes in the bootstrap (NULL) class loader.
227 loader_data->add_class(ik);
229 Atomic::inc(&_total_instanceKlass_count);
230 return ik;
231 }
234 // copy method ordering from resource area to Metaspace
235 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
236 if (m != NULL) {
237 // allocate a new array and copy contents (memcpy?)
238 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
239 for (int i = 0; i < m->length(); i++) {
240 _method_ordering->at_put(i, m->at(i));
241 }
242 } else {
243 _method_ordering = Universe::the_empty_int_array();
244 }
245 }
247 // create a new array of vtable_indices for default methods
248 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
249 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
250 assert(default_vtable_indices() == NULL, "only create once");
251 set_default_vtable_indices(vtable_indices);
252 return vtable_indices;
253 }
255 InstanceKlass::InstanceKlass(int vtable_len,
256 int itable_len,
257 int static_field_size,
258 int nonstatic_oop_map_size,
259 ReferenceType rt,
260 AccessFlags access_flags,
261 bool is_anonymous) {
262 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
264 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
265 access_flags.is_interface(), is_anonymous);
267 set_vtable_length(vtable_len);
268 set_itable_length(itable_len);
269 set_static_field_size(static_field_size);
270 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
271 set_access_flags(access_flags);
272 _misc_flags = 0; // initialize to zero
273 set_is_anonymous(is_anonymous);
274 assert(size() == iksize, "wrong size for object");
276 set_array_klasses(NULL);
277 set_methods(NULL);
278 set_method_ordering(NULL);
279 set_default_methods(NULL);
280 set_default_vtable_indices(NULL);
281 set_local_interfaces(NULL);
282 set_transitive_interfaces(NULL);
283 init_implementor();
284 set_fields(NULL, 0);
285 set_constants(NULL);
286 set_class_loader_data(NULL);
287 set_source_file_name_index(0);
288 set_source_debug_extension(NULL, 0);
289 set_array_name(NULL);
290 set_inner_classes(NULL);
291 set_static_oop_field_count(0);
292 set_nonstatic_field_size(0);
293 set_is_marked_dependent(false);
294 set_has_unloaded_dependent(false);
295 set_init_state(InstanceKlass::allocated);
296 set_init_thread(NULL);
297 set_reference_type(rt);
298 set_oop_map_cache(NULL);
299 set_jni_ids(NULL);
300 set_osr_nmethods_head(NULL);
301 set_breakpoints(NULL);
302 init_previous_versions();
303 set_generic_signature_index(0);
304 release_set_methods_jmethod_ids(NULL);
305 set_annotations(NULL);
306 set_jvmti_cached_class_field_map(NULL);
307 set_initial_method_idnum(0);
308 _dependencies = NULL;
309 set_jvmti_cached_class_field_map(NULL);
310 set_cached_class_file(NULL);
311 set_initial_method_idnum(0);
312 set_minor_version(0);
313 set_major_version(0);
314 NOT_PRODUCT(_verify_count = 0;)
316 // initialize the non-header words to zero
317 intptr_t* p = (intptr_t*)this;
318 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
319 p[index] = NULL_WORD;
320 }
322 // Set temporary value until parseClassFile updates it with the real instance
323 // size.
324 set_layout_helper(Klass::instance_layout_helper(0, true));
325 }
328 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
329 Array<Method*>* methods) {
330 if (methods != NULL && methods != Universe::the_empty_method_array() &&
331 !methods->is_shared()) {
332 for (int i = 0; i < methods->length(); i++) {
333 Method* method = methods->at(i);
334 if (method == NULL) continue; // maybe null if error processing
335 // Only want to delete methods that are not executing for RedefineClasses.
336 // The previous version will point to them so they're not totally dangling
337 assert (!method->on_stack(), "shouldn't be called with methods on stack");
338 MetadataFactory::free_metadata(loader_data, method);
339 }
340 MetadataFactory::free_array<Method*>(loader_data, methods);
341 }
342 }
344 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
345 Klass* super_klass,
346 Array<Klass*>* local_interfaces,
347 Array<Klass*>* transitive_interfaces) {
348 // Only deallocate transitive interfaces if not empty, same as super class
349 // or same as local interfaces. See code in parseClassFile.
350 Array<Klass*>* ti = transitive_interfaces;
351 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
352 // check that the interfaces don't come from super class
353 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
354 InstanceKlass::cast(super_klass)->transitive_interfaces();
355 if (ti != sti && ti != NULL && !ti->is_shared()) {
356 MetadataFactory::free_array<Klass*>(loader_data, ti);
357 }
358 }
360 // local interfaces can be empty
361 if (local_interfaces != Universe::the_empty_klass_array() &&
362 local_interfaces != NULL && !local_interfaces->is_shared()) {
363 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
364 }
365 }
367 // This function deallocates the metadata and C heap pointers that the
368 // InstanceKlass points to.
369 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
371 // Orphan the mirror first, CMS thinks it's still live.
372 if (java_mirror() != NULL) {
373 java_lang_Class::set_klass(java_mirror(), NULL);
374 }
376 // Need to take this class off the class loader data list.
377 loader_data->remove_class(this);
379 // The array_klass for this class is created later, after error handling.
380 // For class redefinition, we keep the original class so this scratch class
381 // doesn't have an array class. Either way, assert that there is nothing
382 // to deallocate.
383 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
385 // Release C heap allocated data that this might point to, which includes
386 // reference counting symbol names.
387 release_C_heap_structures();
389 deallocate_methods(loader_data, methods());
390 set_methods(NULL);
392 if (method_ordering() != NULL &&
393 method_ordering() != Universe::the_empty_int_array() &&
394 !method_ordering()->is_shared()) {
395 MetadataFactory::free_array<int>(loader_data, method_ordering());
396 }
397 set_method_ordering(NULL);
399 // default methods can be empty
400 if (default_methods() != NULL &&
401 default_methods() != Universe::the_empty_method_array() &&
402 !default_methods()->is_shared()) {
403 MetadataFactory::free_array<Method*>(loader_data, default_methods());
404 }
405 // Do NOT deallocate the default methods, they are owned by superinterfaces.
406 set_default_methods(NULL);
408 // default methods vtable indices can be empty
409 if (default_vtable_indices() != NULL &&
410 !default_vtable_indices()->is_shared()) {
411 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
412 }
413 set_default_vtable_indices(NULL);
416 // This array is in Klass, but remove it with the InstanceKlass since
417 // this place would be the only caller and it can share memory with transitive
418 // interfaces.
419 if (secondary_supers() != NULL &&
420 secondary_supers() != Universe::the_empty_klass_array() &&
421 secondary_supers() != transitive_interfaces() &&
422 !secondary_supers()->is_shared()) {
423 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
424 }
425 set_secondary_supers(NULL);
427 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
428 set_transitive_interfaces(NULL);
429 set_local_interfaces(NULL);
431 if (fields() != NULL && !fields()->is_shared()) {
432 MetadataFactory::free_array<jushort>(loader_data, fields());
433 }
434 set_fields(NULL, 0);
436 // If a method from a redefined class is using this constant pool, don't
437 // delete it, yet. The new class's previous version will point to this.
438 if (constants() != NULL) {
439 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
440 if (!constants()->is_shared()) {
441 MetadataFactory::free_metadata(loader_data, constants());
442 }
443 // Delete any cached resolution errors for the constant pool
444 SystemDictionary::delete_resolution_error(constants());
446 set_constants(NULL);
447 }
449 if (inner_classes() != NULL &&
450 inner_classes() != Universe::the_empty_short_array() &&
451 !inner_classes()->is_shared()) {
452 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
453 }
454 set_inner_classes(NULL);
456 // We should deallocate the Annotations instance if it's not in shared spaces.
457 if (annotations() != NULL && !annotations()->is_shared()) {
458 MetadataFactory::free_metadata(loader_data, annotations());
459 }
460 set_annotations(NULL);
461 }
463 bool InstanceKlass::should_be_initialized() const {
464 return !is_initialized();
465 }
467 klassVtable* InstanceKlass::vtable() const {
468 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
469 }
471 klassItable* InstanceKlass::itable() const {
472 return new klassItable(instanceKlassHandle(this));
473 }
475 void InstanceKlass::eager_initialize(Thread *thread) {
476 if (!EagerInitialization) return;
478 if (this->is_not_initialized()) {
479 // abort if the the class has a class initializer
480 if (this->class_initializer() != NULL) return;
482 // abort if it is java.lang.Object (initialization is handled in genesis)
483 Klass* super = this->super();
484 if (super == NULL) return;
486 // abort if the super class should be initialized
487 if (!InstanceKlass::cast(super)->is_initialized()) return;
489 // call body to expose the this pointer
490 instanceKlassHandle this_oop(thread, this);
491 eager_initialize_impl(this_oop);
492 }
493 }
495 // JVMTI spec thinks there are signers and protection domain in the
496 // instanceKlass. These accessors pretend these fields are there.
497 // The hprof specification also thinks these fields are in InstanceKlass.
498 oop InstanceKlass::protection_domain() const {
499 // return the protection_domain from the mirror
500 return java_lang_Class::protection_domain(java_mirror());
501 }
503 // To remove these from requires an incompatible change and CCC request.
504 objArrayOop InstanceKlass::signers() const {
505 // return the signers from the mirror
506 return java_lang_Class::signers(java_mirror());
507 }
509 oop InstanceKlass::init_lock() const {
510 // return the init lock from the mirror
511 oop lock = java_lang_Class::init_lock(java_mirror());
512 // Prevent reordering with any access of initialization state
513 OrderAccess::loadload();
514 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
515 "only fully initialized state can have a null lock");
516 return lock;
517 }
519 // Set the initialization lock to null so the object can be GC'ed. Any racing
520 // threads to get this lock will see a null lock and will not lock.
521 // That's okay because they all check for initialized state after getting
522 // the lock and return.
523 void InstanceKlass::fence_and_clear_init_lock() {
524 // make sure previous stores are all done, notably the init_state.
525 OrderAccess::storestore();
526 java_lang_Class::set_init_lock(java_mirror(), NULL);
527 assert(!is_not_initialized(), "class must be initialized now");
528 }
530 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
531 EXCEPTION_MARK;
532 oop init_lock = this_oop->init_lock();
533 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
535 // abort if someone beat us to the initialization
536 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
538 ClassState old_state = this_oop->init_state();
539 link_class_impl(this_oop, true, THREAD);
540 if (HAS_PENDING_EXCEPTION) {
541 CLEAR_PENDING_EXCEPTION;
542 // Abort if linking the class throws an exception.
544 // Use a test to avoid redundantly resetting the state if there's
545 // no change. Set_init_state() asserts that state changes make
546 // progress, whereas here we might just be spinning in place.
547 if( old_state != this_oop->_init_state )
548 this_oop->set_init_state (old_state);
549 } else {
550 // linking successfull, mark class as initialized
551 this_oop->set_init_state (fully_initialized);
552 this_oop->fence_and_clear_init_lock();
553 // trace
554 if (TraceClassInitialization) {
555 ResourceMark rm(THREAD);
556 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
557 }
558 }
559 }
562 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
563 // process. The step comments refers to the procedure described in that section.
564 // Note: implementation moved to static method to expose the this pointer.
565 void InstanceKlass::initialize(TRAPS) {
566 if (this->should_be_initialized()) {
567 HandleMark hm(THREAD);
568 instanceKlassHandle this_oop(THREAD, this);
569 initialize_impl(this_oop, CHECK);
570 // Note: at this point the class may be initialized
571 // OR it may be in the state of being initialized
572 // in case of recursive initialization!
573 } else {
574 assert(is_initialized(), "sanity check");
575 }
576 }
579 bool InstanceKlass::verify_code(
580 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
581 // 1) Verify the bytecodes
582 Verifier::Mode mode =
583 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
584 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
585 }
588 // Used exclusively by the shared spaces dump mechanism to prevent
589 // classes mapped into the shared regions in new VMs from appearing linked.
591 void InstanceKlass::unlink_class() {
592 assert(is_linked(), "must be linked");
593 _init_state = loaded;
594 }
596 void InstanceKlass::link_class(TRAPS) {
597 assert(is_loaded(), "must be loaded");
598 if (!is_linked()) {
599 HandleMark hm(THREAD);
600 instanceKlassHandle this_oop(THREAD, this);
601 link_class_impl(this_oop, true, CHECK);
602 }
603 }
605 // Called to verify that a class can link during initialization, without
606 // throwing a VerifyError.
607 bool InstanceKlass::link_class_or_fail(TRAPS) {
608 assert(is_loaded(), "must be loaded");
609 if (!is_linked()) {
610 HandleMark hm(THREAD);
611 instanceKlassHandle this_oop(THREAD, this);
612 link_class_impl(this_oop, false, CHECK_false);
613 }
614 return is_linked();
615 }
617 bool InstanceKlass::link_class_impl(
618 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
619 // check for error state
620 if (this_oop->is_in_error_state()) {
621 ResourceMark rm(THREAD);
622 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
623 this_oop->external_name(), false);
624 }
625 // return if already verified
626 if (this_oop->is_linked()) {
627 return true;
628 }
630 // Timing
631 // timer handles recursion
632 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
633 JavaThread* jt = (JavaThread*)THREAD;
635 // link super class before linking this class
636 instanceKlassHandle super(THREAD, this_oop->super());
637 if (super.not_null()) {
638 if (super->is_interface()) { // check if super class is an interface
639 ResourceMark rm(THREAD);
640 Exceptions::fthrow(
641 THREAD_AND_LOCATION,
642 vmSymbols::java_lang_IncompatibleClassChangeError(),
643 "class %s has interface %s as super class",
644 this_oop->external_name(),
645 super->external_name()
646 );
647 return false;
648 }
650 link_class_impl(super, throw_verifyerror, CHECK_false);
651 }
653 // link all interfaces implemented by this class before linking this class
654 Array<Klass*>* interfaces = this_oop->local_interfaces();
655 int num_interfaces = interfaces->length();
656 for (int index = 0; index < num_interfaces; index++) {
657 HandleMark hm(THREAD);
658 instanceKlassHandle ih(THREAD, interfaces->at(index));
659 link_class_impl(ih, throw_verifyerror, CHECK_false);
660 }
662 // in case the class is linked in the process of linking its superclasses
663 if (this_oop->is_linked()) {
664 return true;
665 }
667 // trace only the link time for this klass that includes
668 // the verification time
669 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
670 ClassLoader::perf_class_link_selftime(),
671 ClassLoader::perf_classes_linked(),
672 jt->get_thread_stat()->perf_recursion_counts_addr(),
673 jt->get_thread_stat()->perf_timers_addr(),
674 PerfClassTraceTime::CLASS_LINK);
676 // verification & rewriting
677 {
678 oop init_lock = this_oop->init_lock();
679 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
680 // rewritten will have been set if loader constraint error found
681 // on an earlier link attempt
682 // don't verify or rewrite if already rewritten
684 if (!this_oop->is_linked()) {
685 if (!this_oop->is_rewritten()) {
686 {
687 // Timer includes any side effects of class verification (resolution,
688 // etc), but not recursive entry into verify_code().
689 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
690 ClassLoader::perf_class_verify_selftime(),
691 ClassLoader::perf_classes_verified(),
692 jt->get_thread_stat()->perf_recursion_counts_addr(),
693 jt->get_thread_stat()->perf_timers_addr(),
694 PerfClassTraceTime::CLASS_VERIFY);
695 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
696 if (!verify_ok) {
697 return false;
698 }
699 }
701 // Just in case a side-effect of verify linked this class already
702 // (which can sometimes happen since the verifier loads classes
703 // using custom class loaders, which are free to initialize things)
704 if (this_oop->is_linked()) {
705 return true;
706 }
708 // also sets rewritten
709 this_oop->rewrite_class(CHECK_false);
710 } else if (this_oop()->is_shared()) {
711 ResourceMark rm(THREAD);
712 char* message_buffer; // res-allocated by check_verification_dependencies
713 Handle loader = this_oop()->class_loader();
714 Handle pd = this_oop()->protection_domain();
715 bool verified = SystemDictionaryShared::check_verification_dependencies(this_oop(),
716 loader, pd, &message_buffer, THREAD);
717 if (!verified) {
718 THROW_MSG_(vmSymbols::java_lang_VerifyError(), message_buffer, false);
719 }
720 }
722 // relocate jsrs and link methods after they are all rewritten
723 this_oop->link_methods(CHECK_false);
725 // Initialize the vtable and interface table after
726 // methods have been rewritten since rewrite may
727 // fabricate new Method*s.
728 // also does loader constraint checking
729 //
730 // Initialize_vtable and initialize_itable need to be rerun for
731 // a shared class if the class is not loaded by the NULL classloader.
732 ClassLoaderData * loader_data = this_oop->class_loader_data();
733 if (!(this_oop()->is_shared() &&
734 loader_data->is_the_null_class_loader_data())) {
735 ResourceMark rm(THREAD);
736 this_oop->vtable()->initialize_vtable(true, CHECK_false);
737 this_oop->itable()->initialize_itable(true, CHECK_false);
738 }
739 #ifdef ASSERT
740 else {
741 ResourceMark rm(THREAD);
742 this_oop->vtable()->verify(tty, true);
743 // In case itable verification is ever added.
744 // this_oop->itable()->verify(tty, true);
745 }
746 #endif
747 this_oop->set_init_state(linked);
748 if (JvmtiExport::should_post_class_prepare()) {
749 Thread *thread = THREAD;
750 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
751 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
752 }
753 }
754 }
755 return true;
756 }
759 // Rewrite the byte codes of all of the methods of a class.
760 // The rewriter must be called exactly once. Rewriting must happen after
761 // verification but before the first method of the class is executed.
762 void InstanceKlass::rewrite_class(TRAPS) {
763 assert(is_loaded(), "must be loaded");
764 instanceKlassHandle this_oop(THREAD, this);
765 if (this_oop->is_rewritten()) {
766 assert(this_oop()->is_shared(), "rewriting an unshared class?");
767 return;
768 }
769 Rewriter::rewrite(this_oop, CHECK);
770 this_oop->set_rewritten();
771 }
773 // Now relocate and link method entry points after class is rewritten.
774 // This is outside is_rewritten flag. In case of an exception, it can be
775 // executed more than once.
776 void InstanceKlass::link_methods(TRAPS) {
777 int len = methods()->length();
778 for (int i = len-1; i >= 0; i--) {
779 methodHandle m(THREAD, methods()->at(i));
781 // Set up method entry points for compiler and interpreter .
782 m->link_method(m, CHECK);
784 // This is for JVMTI and unrelated to relocator but the last thing we do
785 #ifdef ASSERT
786 if (StressMethodComparator) {
787 ResourceMark rm(THREAD);
788 static int nmc = 0;
789 for (int j = i; j >= 0 && j >= i-4; j--) {
790 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
791 bool z = MethodComparator::methods_EMCP(m(),
792 methods()->at(j));
793 if (j == i && !z) {
794 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
795 assert(z, "method must compare equal to itself");
796 }
797 }
798 }
799 #endif //ASSERT
800 }
801 }
803 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
804 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_oop, TRAPS) {
805 if (this_oop->has_default_methods()) {
806 for (int i = 0; i < this_oop->local_interfaces()->length(); ++i) {
807 Klass* iface = this_oop->local_interfaces()->at(i);
808 InstanceKlass* ik = InstanceKlass::cast(iface);
809 if (ik->should_be_initialized()) {
810 if (ik->has_default_methods()) {
811 ik->initialize_super_interfaces(ik, THREAD);
812 }
813 // Only initialize() interfaces that "declare" concrete methods.
814 // has_default_methods drives searching superinterfaces since it
815 // means has_default_methods in its superinterface hierarchy
816 if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) {
817 ik->initialize(THREAD);
818 }
819 if (HAS_PENDING_EXCEPTION) {
820 Handle e(THREAD, PENDING_EXCEPTION);
821 CLEAR_PENDING_EXCEPTION;
822 {
823 EXCEPTION_MARK;
824 // Locks object, set state, and notify all waiting threads
825 this_oop->set_initialization_state_and_notify(
826 initialization_error, THREAD);
828 // ignore any exception thrown, superclass initialization error is
829 // thrown below
830 CLEAR_PENDING_EXCEPTION;
831 }
832 THROW_OOP(e());
833 }
834 }
835 }
836 }
837 }
839 void InstanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
840 // Make sure klass is linked (verified) before initialization
841 // A class could already be verified, since it has been reflected upon.
842 this_oop->link_class(CHECK);
844 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_oop()), -1);
846 bool wait = false;
848 // refer to the JVM book page 47 for description of steps
849 // Step 1
850 {
851 oop init_lock = this_oop->init_lock();
852 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
854 Thread *self = THREAD; // it's passed the current thread
856 // Step 2
857 // If we were to use wait() instead of waitInterruptibly() then
858 // we might end up throwing IE from link/symbol resolution sites
859 // that aren't expected to throw. This would wreak havoc. See 6320309.
860 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
861 wait = true;
862 ol.waitUninterruptibly(CHECK);
863 }
865 // Step 3
866 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
867 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_oop()), -1,wait);
868 return;
869 }
871 // Step 4
872 if (this_oop->is_initialized()) {
873 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_oop()), -1,wait);
874 return;
875 }
877 // Step 5
878 if (this_oop->is_in_error_state()) {
879 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_oop()), -1,wait);
880 ResourceMark rm(THREAD);
881 const char* desc = "Could not initialize class ";
882 const char* className = this_oop->external_name();
883 size_t msglen = strlen(desc) + strlen(className) + 1;
884 char* message = NEW_RESOURCE_ARRAY(char, msglen);
885 if (NULL == message) {
886 // Out of memory: can't create detailed error message
887 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
888 } else {
889 jio_snprintf(message, msglen, "%s%s", desc, className);
890 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
891 }
892 }
894 // Step 6
895 this_oop->set_init_state(being_initialized);
896 this_oop->set_init_thread(self);
897 }
899 // Step 7
900 Klass* super_klass = this_oop->super();
901 if (super_klass != NULL && !this_oop->is_interface() && super_klass->should_be_initialized()) {
902 super_klass->initialize(THREAD);
904 if (HAS_PENDING_EXCEPTION) {
905 Handle e(THREAD, PENDING_EXCEPTION);
906 CLEAR_PENDING_EXCEPTION;
907 {
908 EXCEPTION_MARK;
909 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
910 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
911 }
912 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_oop()), -1,wait);
913 THROW_OOP(e());
914 }
915 }
917 // Recursively initialize any superinterfaces that declare default methods
918 // Only need to recurse if has_default_methods which includes declaring and
919 // inheriting default methods
920 if (this_oop->has_default_methods()) {
921 this_oop->initialize_super_interfaces(this_oop, CHECK);
922 }
924 // Step 8
925 {
926 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
927 JavaThread* jt = (JavaThread*)THREAD;
928 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_oop()), -1,wait);
929 // Timer includes any side effects of class initialization (resolution,
930 // etc), but not recursive entry into call_class_initializer().
931 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
932 ClassLoader::perf_class_init_selftime(),
933 ClassLoader::perf_classes_inited(),
934 jt->get_thread_stat()->perf_recursion_counts_addr(),
935 jt->get_thread_stat()->perf_timers_addr(),
936 PerfClassTraceTime::CLASS_CLINIT);
937 this_oop->call_class_initializer(THREAD);
938 }
940 // Step 9
941 if (!HAS_PENDING_EXCEPTION) {
942 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
943 { ResourceMark rm(THREAD);
944 debug_only(this_oop->vtable()->verify(tty, true);)
945 }
946 }
947 else {
948 // Step 10 and 11
949 Handle e(THREAD, PENDING_EXCEPTION);
950 CLEAR_PENDING_EXCEPTION;
951 // JVMTI has already reported the pending exception
952 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
953 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
954 {
955 EXCEPTION_MARK;
956 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
957 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
958 // JVMTI has already reported the pending exception
959 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
960 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
961 }
962 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_oop()), -1,wait);
963 if (e->is_a(SystemDictionary::Error_klass())) {
964 THROW_OOP(e());
965 } else {
966 JavaCallArguments args(e);
967 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
968 vmSymbols::throwable_void_signature(),
969 &args);
970 }
971 }
972 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_oop()), -1,wait);
973 }
976 // Note: implementation moved to static method to expose the this pointer.
977 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
978 instanceKlassHandle kh(THREAD, this);
979 set_initialization_state_and_notify_impl(kh, state, CHECK);
980 }
982 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
983 oop init_lock = this_oop->init_lock();
984 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
985 this_oop->set_init_state(state);
986 this_oop->fence_and_clear_init_lock();
987 ol.notify_all(CHECK);
988 }
990 // The embedded _implementor field can only record one implementor.
991 // When there are more than one implementors, the _implementor field
992 // is set to the interface Klass* itself. Following are the possible
993 // values for the _implementor field:
994 // NULL - no implementor
995 // implementor Klass* - one implementor
996 // self - more than one implementor
997 //
998 // The _implementor field only exists for interfaces.
999 void InstanceKlass::add_implementor(Klass* k) {
1000 assert(Compile_lock->owned_by_self(), "");
1001 assert(is_interface(), "not interface");
1002 // Filter out my subinterfaces.
1003 // (Note: Interfaces are never on the subklass list.)
1004 if (InstanceKlass::cast(k)->is_interface()) return;
1006 // Filter out subclasses whose supers already implement me.
1007 // (Note: CHA must walk subclasses of direct implementors
1008 // in order to locate indirect implementors.)
1009 Klass* sk = InstanceKlass::cast(k)->super();
1010 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1011 // We only need to check one immediate superclass, since the
1012 // implements_interface query looks at transitive_interfaces.
1013 // Any supers of the super have the same (or fewer) transitive_interfaces.
1014 return;
1016 Klass* ik = implementor();
1017 if (ik == NULL) {
1018 set_implementor(k);
1019 } else if (ik != this) {
1020 // There is already an implementor. Use itself as an indicator of
1021 // more than one implementors.
1022 set_implementor(this);
1023 }
1025 // The implementor also implements the transitive_interfaces
1026 for (int index = 0; index < local_interfaces()->length(); index++) {
1027 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1028 }
1029 }
1031 void InstanceKlass::init_implementor() {
1032 if (is_interface()) {
1033 set_implementor(NULL);
1034 }
1035 }
1038 void InstanceKlass::process_interfaces(Thread *thread) {
1039 // link this class into the implementors list of every interface it implements
1040 Klass* this_as_klass_oop = this;
1041 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1042 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1043 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1044 assert(interf->is_interface(), "expected interface");
1045 interf->add_implementor(this_as_klass_oop);
1046 }
1047 }
1049 bool InstanceKlass::can_be_primary_super_slow() const {
1050 if (is_interface())
1051 return false;
1052 else
1053 return Klass::can_be_primary_super_slow();
1054 }
1056 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1057 // The secondaries are the implemented interfaces.
1058 InstanceKlass* ik = InstanceKlass::cast(this);
1059 Array<Klass*>* interfaces = ik->transitive_interfaces();
1060 int num_secondaries = num_extra_slots + interfaces->length();
1061 if (num_secondaries == 0) {
1062 // Must share this for correct bootstrapping!
1063 set_secondary_supers(Universe::the_empty_klass_array());
1064 return NULL;
1065 } else if (num_extra_slots == 0) {
1066 // The secondary super list is exactly the same as the transitive interfaces.
1067 // Redefine classes has to be careful not to delete this!
1068 set_secondary_supers(interfaces);
1069 return NULL;
1070 } else {
1071 // Copy transitive interfaces to a temporary growable array to be constructed
1072 // into the secondary super list with extra slots.
1073 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1074 for (int i = 0; i < interfaces->length(); i++) {
1075 secondaries->push(interfaces->at(i));
1076 }
1077 return secondaries;
1078 }
1079 }
1081 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1082 if (k->is_interface()) {
1083 return implements_interface(k);
1084 } else {
1085 return Klass::compute_is_subtype_of(k);
1086 }
1087 }
1089 bool InstanceKlass::implements_interface(Klass* k) const {
1090 if (this == k) return true;
1091 assert(k->is_interface(), "should be an interface class");
1092 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1093 if (transitive_interfaces()->at(i) == k) {
1094 return true;
1095 }
1096 }
1097 return false;
1098 }
1100 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1101 // Verify direct super interface
1102 if (this == k) return true;
1103 assert(k->is_interface(), "should be an interface class");
1104 for (int i = 0; i < local_interfaces()->length(); i++) {
1105 if (local_interfaces()->at(i) == k) {
1106 return true;
1107 }
1108 }
1109 return false;
1110 }
1112 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1113 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1114 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1115 report_java_out_of_memory("Requested array size exceeds VM limit");
1116 JvmtiExport::post_array_size_exhausted();
1117 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1118 }
1119 int size = objArrayOopDesc::object_size(length);
1120 Klass* ak = array_klass(n, CHECK_NULL);
1121 KlassHandle h_ak (THREAD, ak);
1122 objArrayOop o =
1123 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1124 return o;
1125 }
1127 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1128 if (TraceFinalizerRegistration) {
1129 tty->print("Registered ");
1130 i->print_value_on(tty);
1131 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
1132 }
1133 instanceHandle h_i(THREAD, i);
1134 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1135 JavaValue result(T_VOID);
1136 JavaCallArguments args(h_i);
1137 methodHandle mh (THREAD, Universe::finalizer_register_method());
1138 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1139 return h_i();
1140 }
1142 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1143 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1144 int size = size_helper(); // Query before forming handle.
1146 KlassHandle h_k(THREAD, this);
1148 instanceOop i;
1150 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1151 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1152 i = register_finalizer(i, CHECK_NULL);
1153 }
1154 return i;
1155 }
1157 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1158 if (is_interface() || is_abstract()) {
1159 ResourceMark rm(THREAD);
1160 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1161 : vmSymbols::java_lang_InstantiationException(), external_name());
1162 }
1163 if (this == SystemDictionary::Class_klass()) {
1164 ResourceMark rm(THREAD);
1165 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1166 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1167 }
1168 }
1170 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1171 instanceKlassHandle this_oop(THREAD, this);
1172 return array_klass_impl(this_oop, or_null, n, THREAD);
1173 }
1175 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
1176 if (this_oop->array_klasses() == NULL) {
1177 if (or_null) return NULL;
1179 ResourceMark rm;
1180 JavaThread *jt = (JavaThread *)THREAD;
1181 {
1182 // Atomic creation of array_klasses
1183 MutexLocker mc(Compile_lock, THREAD); // for vtables
1184 MutexLocker ma(MultiArray_lock, THREAD);
1186 // Check if update has already taken place
1187 if (this_oop->array_klasses() == NULL) {
1188 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_oop->class_loader_data(), 1, this_oop, CHECK_NULL);
1189 this_oop->set_array_klasses(k);
1190 }
1191 }
1192 }
1193 // _this will always be set at this point
1194 ObjArrayKlass* oak = (ObjArrayKlass*)this_oop->array_klasses();
1195 if (or_null) {
1196 return oak->array_klass_or_null(n);
1197 }
1198 return oak->array_klass(n, CHECK_NULL);
1199 }
1201 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1202 return array_klass_impl(or_null, 1, THREAD);
1203 }
1205 void InstanceKlass::call_class_initializer(TRAPS) {
1206 instanceKlassHandle ik (THREAD, this);
1207 call_class_initializer_impl(ik, THREAD);
1208 }
1210 static int call_class_initializer_impl_counter = 0; // for debugging
1212 Method* InstanceKlass::class_initializer() {
1213 Method* clinit = find_method(
1214 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1215 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1216 return clinit;
1217 }
1218 return NULL;
1219 }
1221 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
1222 if (ReplayCompiles &&
1223 (ReplaySuppressInitializers == 1 ||
1224 ReplaySuppressInitializers >= 2 && this_oop->class_loader() != NULL)) {
1225 // Hide the existence of the initializer for the purpose of replaying the compile
1226 return;
1227 }
1229 methodHandle h_method(THREAD, this_oop->class_initializer());
1230 assert(!this_oop->is_initialized(), "we cannot initialize twice");
1231 if (TraceClassInitialization) {
1232 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1233 this_oop->name()->print_value();
1234 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
1235 }
1236 if (h_method() != NULL) {
1237 JavaCallArguments args; // No arguments
1238 JavaValue result(T_VOID);
1239 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1240 }
1241 }
1244 void InstanceKlass::mask_for(methodHandle method, int bci,
1245 InterpreterOopMap* entry_for) {
1246 // Dirty read, then double-check under a lock.
1247 if (_oop_map_cache == NULL) {
1248 // Otherwise, allocate a new one.
1249 MutexLocker x(OopMapCacheAlloc_lock);
1250 // First time use. Allocate a cache in C heap
1251 if (_oop_map_cache == NULL) {
1252 // Release stores from OopMapCache constructor before assignment
1253 // to _oop_map_cache. C++ compilers on ppc do not emit the
1254 // required memory barrier only because of the volatile
1255 // qualifier of _oop_map_cache.
1256 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1257 }
1258 }
1259 // _oop_map_cache is constant after init; lookup below does is own locking.
1260 _oop_map_cache->lookup(method, bci, entry_for);
1261 }
1264 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1265 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1266 Symbol* f_name = fs.name();
1267 Symbol* f_sig = fs.signature();
1268 if (f_name == name && f_sig == sig) {
1269 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1270 return true;
1271 }
1272 }
1273 return false;
1274 }
1277 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1278 const int n = local_interfaces()->length();
1279 for (int i = 0; i < n; i++) {
1280 Klass* intf1 = local_interfaces()->at(i);
1281 assert(intf1->is_interface(), "just checking type");
1282 // search for field in current interface
1283 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1284 assert(fd->is_static(), "interface field must be static");
1285 return intf1;
1286 }
1287 // search for field in direct superinterfaces
1288 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1289 if (intf2 != NULL) return intf2;
1290 }
1291 // otherwise field lookup fails
1292 return NULL;
1293 }
1296 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1297 // search order according to newest JVM spec (5.4.3.2, p.167).
1298 // 1) search for field in current klass
1299 if (find_local_field(name, sig, fd)) {
1300 return const_cast<InstanceKlass*>(this);
1301 }
1302 // 2) search for field recursively in direct superinterfaces
1303 { Klass* intf = find_interface_field(name, sig, fd);
1304 if (intf != NULL) return intf;
1305 }
1306 // 3) apply field lookup recursively if superclass exists
1307 { Klass* supr = super();
1308 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1309 }
1310 // 4) otherwise field lookup fails
1311 return NULL;
1312 }
1315 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1316 // search order according to newest JVM spec (5.4.3.2, p.167).
1317 // 1) search for field in current klass
1318 if (find_local_field(name, sig, fd)) {
1319 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1320 }
1321 // 2) search for field recursively in direct superinterfaces
1322 if (is_static) {
1323 Klass* intf = find_interface_field(name, sig, fd);
1324 if (intf != NULL) return intf;
1325 }
1326 // 3) apply field lookup recursively if superclass exists
1327 { Klass* supr = super();
1328 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1329 }
1330 // 4) otherwise field lookup fails
1331 return NULL;
1332 }
1335 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1336 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1337 if (fs.offset() == offset) {
1338 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1339 if (fd->is_static() == is_static) return true;
1340 }
1341 }
1342 return false;
1343 }
1346 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1347 Klass* klass = const_cast<InstanceKlass*>(this);
1348 while (klass != NULL) {
1349 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1350 return true;
1351 }
1352 klass = klass->super();
1353 }
1354 return false;
1355 }
1358 void InstanceKlass::methods_do(void f(Method* method)) {
1359 int len = methods()->length();
1360 for (int index = 0; index < len; index++) {
1361 Method* m = methods()->at(index);
1362 assert(m->is_method(), "must be method");
1363 f(m);
1364 }
1365 }
1368 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1369 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1370 if (fs.access_flags().is_static()) {
1371 fieldDescriptor& fd = fs.field_descriptor();
1372 cl->do_field(&fd);
1373 }
1374 }
1375 }
1378 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1379 instanceKlassHandle h_this(THREAD, this);
1380 do_local_static_fields_impl(h_this, f, mirror, CHECK);
1381 }
1384 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1385 void f(fieldDescriptor* fd, Handle mirror, TRAPS), Handle mirror, TRAPS) {
1386 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1387 if (fs.access_flags().is_static()) {
1388 fieldDescriptor& fd = fs.field_descriptor();
1389 f(&fd, mirror, CHECK);
1390 }
1391 }
1392 }
1395 static int compare_fields_by_offset(int* a, int* b) {
1396 return a[0] - b[0];
1397 }
1399 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1400 InstanceKlass* super = superklass();
1401 if (super != NULL) {
1402 super->do_nonstatic_fields(cl);
1403 }
1404 fieldDescriptor fd;
1405 int length = java_fields_count();
1406 // In DebugInfo nonstatic fields are sorted by offset.
1407 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1408 int j = 0;
1409 for (int i = 0; i < length; i += 1) {
1410 fd.reinitialize(this, i);
1411 if (!fd.is_static()) {
1412 fields_sorted[j + 0] = fd.offset();
1413 fields_sorted[j + 1] = i;
1414 j += 2;
1415 }
1416 }
1417 if (j > 0) {
1418 length = j;
1419 // _sort_Fn is defined in growableArray.hpp.
1420 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1421 for (int i = 0; i < length; i += 2) {
1422 fd.reinitialize(this, fields_sorted[i + 1]);
1423 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1424 cl->do_field(&fd);
1425 }
1426 }
1427 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1428 }
1431 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1432 if (array_klasses() != NULL)
1433 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1434 }
1436 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1437 if (array_klasses() != NULL)
1438 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1439 }
1441 #ifdef ASSERT
1442 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1443 int len = methods->length();
1444 for (int index = 0; index < len; index++) {
1445 Method* m = methods->at(index);
1446 assert(m->is_method(), "must be method");
1447 if (m->signature() == signature && m->name() == name) {
1448 return index;
1449 }
1450 }
1451 return -1;
1452 }
1453 #endif
1455 static int binary_search(Array<Method*>* methods, Symbol* name) {
1456 int len = methods->length();
1457 // methods are sorted, so do binary search
1458 int l = 0;
1459 int h = len - 1;
1460 while (l <= h) {
1461 int mid = (l + h) >> 1;
1462 Method* m = methods->at(mid);
1463 assert(m->is_method(), "must be method");
1464 int res = m->name()->fast_compare(name);
1465 if (res == 0) {
1466 return mid;
1467 } else if (res < 0) {
1468 l = mid + 1;
1469 } else {
1470 h = mid - 1;
1471 }
1472 }
1473 return -1;
1474 }
1476 // find_method looks up the name/signature in the local methods array
1477 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1478 return find_method_impl(name, signature, false);
1479 }
1481 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const {
1482 return InstanceKlass::find_method_impl(methods(), name, signature, skipping_overpass, false);
1483 }
1485 // find_instance_method looks up the name/signature in the local methods array
1486 // and skips over static methods
1487 Method* InstanceKlass::find_instance_method(
1488 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1489 Method* meth = InstanceKlass::find_method_impl(methods, name, signature, false, true);
1490 return meth;
1491 }
1493 // find_instance_method looks up the name/signature in the local methods array
1494 // and skips over static methods
1495 Method* InstanceKlass::find_instance_method(Symbol* name, Symbol* signature) {
1496 return InstanceKlass::find_instance_method(methods(), name, signature);
1497 }
1499 // find_method looks up the name/signature in the local methods array
1500 Method* InstanceKlass::find_method(
1501 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1502 return InstanceKlass::find_method_impl(methods, name, signature, false, false);
1503 }
1505 Method* InstanceKlass::find_method_impl(
1506 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass, bool skipping_static) {
1507 int hit = find_method_index(methods, name, signature, skipping_overpass, skipping_static);
1508 return hit >= 0 ? methods->at(hit): NULL;
1509 }
1511 bool InstanceKlass::method_matches(Method* m, Symbol* signature, bool skipping_overpass, bool skipping_static) {
1512 return (m->signature() == signature) &&
1513 (!skipping_overpass || !m->is_overpass()) &&
1514 (!skipping_static || !m->is_static());
1515 }
1517 // Used directly for default_methods to find the index into the
1518 // default_vtable_indices, and indirectly by find_method
1519 // find_method_index looks in the local methods array to return the index
1520 // of the matching name/signature. If, overpass methods are being ignored,
1521 // the search continues to find a potential non-overpass match. This capability
1522 // is important during method resolution to prefer a static method, for example,
1523 // over an overpass method.
1524 int InstanceKlass::find_method_index(
1525 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass, bool skipping_static) {
1526 int hit = binary_search(methods, name);
1527 if (hit != -1) {
1528 Method* m = methods->at(hit);
1530 // Do linear search to find matching signature. First, quick check
1531 // for common case, ignoring overpasses if requested.
1532 if (method_matches(m, signature, skipping_overpass, skipping_static)) return hit;
1534 // search downwards through overloaded methods
1535 int i;
1536 for (i = hit - 1; i >= 0; --i) {
1537 Method* m = methods->at(i);
1538 assert(m->is_method(), "must be method");
1539 if (m->name() != name) break;
1540 if (method_matches(m, signature, skipping_overpass, skipping_static)) return i;
1541 }
1542 // search upwards
1543 for (i = hit + 1; i < methods->length(); ++i) {
1544 Method* m = methods->at(i);
1545 assert(m->is_method(), "must be method");
1546 if (m->name() != name) break;
1547 if (method_matches(m, signature, skipping_overpass, skipping_static)) return i;
1548 }
1549 // not found
1550 #ifdef ASSERT
1551 int index = skipping_overpass || skipping_static ? -1 : linear_search(methods, name, signature);
1552 assert(index == -1, err_msg("binary search should have found entry %d", index));
1553 #endif
1554 }
1555 return -1;
1556 }
1557 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1558 return find_method_by_name(methods(), name, end);
1559 }
1561 int InstanceKlass::find_method_by_name(
1562 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1563 assert(end_ptr != NULL, "just checking");
1564 int start = binary_search(methods, name);
1565 int end = start + 1;
1566 if (start != -1) {
1567 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1568 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1569 *end_ptr = end;
1570 return start;
1571 }
1572 return -1;
1573 }
1575 // uncached_lookup_method searches both the local class methods array and all
1576 // superclasses methods arrays, skipping any overpass methods in superclasses.
1577 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const {
1578 MethodLookupMode lookup_mode = mode;
1579 Klass* klass = const_cast<InstanceKlass*>(this);
1580 while (klass != NULL) {
1581 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, (lookup_mode == skip_overpass));
1582 if (method != NULL) {
1583 return method;
1584 }
1585 klass = InstanceKlass::cast(klass)->super();
1586 lookup_mode = skip_overpass; // Always ignore overpass methods in superclasses
1587 }
1588 return NULL;
1589 }
1591 #ifdef ASSERT
1592 // search through class hierarchy and return true if this class or
1593 // one of the superclasses was redefined
1594 bool InstanceKlass::has_redefined_this_or_super() const {
1595 const InstanceKlass* klass = this;
1596 while (klass != NULL) {
1597 if (klass->has_been_redefined()) {
1598 return true;
1599 }
1600 klass = InstanceKlass::cast(klass->super());
1601 }
1602 return false;
1603 }
1604 #endif
1606 // lookup a method in the default methods list then in all transitive interfaces
1607 // Do NOT return private or static methods
1608 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1609 Symbol* signature) const {
1610 Method* m = NULL;
1611 if (default_methods() != NULL) {
1612 m = find_method(default_methods(), name, signature);
1613 }
1614 // Look up interfaces
1615 if (m == NULL) {
1616 m = lookup_method_in_all_interfaces(name, signature, normal);
1617 }
1618 return m;
1619 }
1621 // lookup a method in all the interfaces that this class implements
1622 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1623 // They should only be found in the initial InterfaceMethodRef
1624 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1625 Symbol* signature,
1626 MethodLookupMode mode) const {
1627 Array<Klass*>* all_ifs = transitive_interfaces();
1628 int num_ifs = all_ifs->length();
1629 InstanceKlass *ik = NULL;
1630 for (int i = 0; i < num_ifs; i++) {
1631 ik = InstanceKlass::cast(all_ifs->at(i));
1632 Method* m = ik->lookup_method(name, signature);
1633 if (m != NULL && m->is_public() && !m->is_static() &&
1634 ((mode != skip_defaults) || !m->is_default_method())) {
1635 return m;
1636 }
1637 }
1638 return NULL;
1639 }
1641 /* jni_id_for_impl for jfieldIds only */
1642 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1643 MutexLocker ml(JfieldIdCreation_lock);
1644 // Retry lookup after we got the lock
1645 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1646 if (probe == NULL) {
1647 // Slow case, allocate new static field identifier
1648 probe = new JNIid(this_oop(), offset, this_oop->jni_ids());
1649 this_oop->set_jni_ids(probe);
1650 }
1651 return probe;
1652 }
1655 /* jni_id_for for jfieldIds only */
1656 JNIid* InstanceKlass::jni_id_for(int offset) {
1657 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1658 if (probe == NULL) {
1659 probe = jni_id_for_impl(this, offset);
1660 }
1661 return probe;
1662 }
1664 u2 InstanceKlass::enclosing_method_data(int offset) {
1665 Array<jushort>* inner_class_list = inner_classes();
1666 if (inner_class_list == NULL) {
1667 return 0;
1668 }
1669 int length = inner_class_list->length();
1670 if (length % inner_class_next_offset == 0) {
1671 return 0;
1672 } else {
1673 int index = length - enclosing_method_attribute_size;
1674 assert(offset < enclosing_method_attribute_size, "invalid offset");
1675 return inner_class_list->at(index + offset);
1676 }
1677 }
1679 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1680 u2 method_index) {
1681 Array<jushort>* inner_class_list = inner_classes();
1682 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1683 int length = inner_class_list->length();
1684 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1685 int index = length - enclosing_method_attribute_size;
1686 inner_class_list->at_put(
1687 index + enclosing_method_class_index_offset, class_index);
1688 inner_class_list->at_put(
1689 index + enclosing_method_method_index_offset, method_index);
1690 }
1691 }
1693 // Lookup or create a jmethodID.
1694 // This code is called by the VMThread and JavaThreads so the
1695 // locking has to be done very carefully to avoid deadlocks
1696 // and/or other cache consistency problems.
1697 //
1698 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1699 size_t idnum = (size_t)method_h->method_idnum();
1700 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1701 size_t length = 0;
1702 jmethodID id = NULL;
1704 // We use a double-check locking idiom here because this cache is
1705 // performance sensitive. In the normal system, this cache only
1706 // transitions from NULL to non-NULL which is safe because we use
1707 // release_set_methods_jmethod_ids() to advertise the new cache.
1708 // A partially constructed cache should never be seen by a racing
1709 // thread. We also use release_store_ptr() to save a new jmethodID
1710 // in the cache so a partially constructed jmethodID should never be
1711 // seen either. Cache reads of existing jmethodIDs proceed without a
1712 // lock, but cache writes of a new jmethodID requires uniqueness and
1713 // creation of the cache itself requires no leaks so a lock is
1714 // generally acquired in those two cases.
1715 //
1716 // If the RedefineClasses() API has been used, then this cache can
1717 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1718 // Cache creation requires no leaks and we require safety between all
1719 // cache accesses and freeing of the old cache so a lock is generally
1720 // acquired when the RedefineClasses() API has been used.
1722 if (jmeths != NULL) {
1723 // the cache already exists
1724 if (!ik_h->idnum_can_increment()) {
1725 // the cache can't grow so we can just get the current values
1726 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1727 } else {
1728 // cache can grow so we have to be more careful
1729 if (Threads::number_of_threads() == 0 ||
1730 SafepointSynchronize::is_at_safepoint()) {
1731 // we're single threaded or at a safepoint - no locking needed
1732 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1733 } else {
1734 MutexLocker ml(JmethodIdCreation_lock);
1735 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1736 }
1737 }
1738 }
1739 // implied else:
1740 // we need to allocate a cache so default length and id values are good
1742 if (jmeths == NULL || // no cache yet
1743 length <= idnum || // cache is too short
1744 id == NULL) { // cache doesn't contain entry
1746 // This function can be called by the VMThread so we have to do all
1747 // things that might block on a safepoint before grabbing the lock.
1748 // Otherwise, we can deadlock with the VMThread or have a cache
1749 // consistency issue. These vars keep track of what we might have
1750 // to free after the lock is dropped.
1751 jmethodID to_dealloc_id = NULL;
1752 jmethodID* to_dealloc_jmeths = NULL;
1754 // may not allocate new_jmeths or use it if we allocate it
1755 jmethodID* new_jmeths = NULL;
1756 if (length <= idnum) {
1757 // allocate a new cache that might be used
1758 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1759 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1760 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1761 // cache size is stored in element[0], other elements offset by one
1762 new_jmeths[0] = (jmethodID)size;
1763 }
1765 // allocate a new jmethodID that might be used
1766 jmethodID new_id = NULL;
1767 if (method_h->is_old() && !method_h->is_obsolete()) {
1768 // The method passed in is old (but not obsolete), we need to use the current version
1769 Method* current_method = ik_h->method_with_idnum((int)idnum);
1770 assert(current_method != NULL, "old and but not obsolete, so should exist");
1771 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1772 } else {
1773 // It is the current version of the method or an obsolete method,
1774 // use the version passed in
1775 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1776 }
1778 if (Threads::number_of_threads() == 0 ||
1779 SafepointSynchronize::is_at_safepoint()) {
1780 // we're single threaded or at a safepoint - no locking needed
1781 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1782 &to_dealloc_id, &to_dealloc_jmeths);
1783 } else {
1784 MutexLocker ml(JmethodIdCreation_lock);
1785 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1786 &to_dealloc_id, &to_dealloc_jmeths);
1787 }
1789 // The lock has been dropped so we can free resources.
1790 // Free up either the old cache or the new cache if we allocated one.
1791 if (to_dealloc_jmeths != NULL) {
1792 FreeHeap(to_dealloc_jmeths);
1793 }
1794 // free up the new ID since it wasn't needed
1795 if (to_dealloc_id != NULL) {
1796 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1797 }
1798 }
1799 return id;
1800 }
1803 // Common code to fetch the jmethodID from the cache or update the
1804 // cache with the new jmethodID. This function should never do anything
1805 // that causes the caller to go to a safepoint or we can deadlock with
1806 // the VMThread or have cache consistency issues.
1807 //
1808 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1809 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1810 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1811 jmethodID** to_dealloc_jmeths_p) {
1812 assert(new_id != NULL, "sanity check");
1813 assert(to_dealloc_id_p != NULL, "sanity check");
1814 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1815 assert(Threads::number_of_threads() == 0 ||
1816 SafepointSynchronize::is_at_safepoint() ||
1817 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1819 // reacquire the cache - we are locked, single threaded or at a safepoint
1820 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1821 jmethodID id = NULL;
1822 size_t length = 0;
1824 if (jmeths == NULL || // no cache yet
1825 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1826 if (jmeths != NULL) {
1827 // copy any existing entries from the old cache
1828 for (size_t index = 0; index < length; index++) {
1829 new_jmeths[index+1] = jmeths[index+1];
1830 }
1831 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1832 }
1833 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1834 } else {
1835 // fetch jmethodID (if any) from the existing cache
1836 id = jmeths[idnum+1];
1837 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1838 }
1839 if (id == NULL) {
1840 // No matching jmethodID in the existing cache or we have a new
1841 // cache or we just grew the cache. This cache write is done here
1842 // by the first thread to win the foot race because a jmethodID
1843 // needs to be unique once it is generally available.
1844 id = new_id;
1846 // The jmethodID cache can be read while unlocked so we have to
1847 // make sure the new jmethodID is complete before installing it
1848 // in the cache.
1849 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1850 } else {
1851 *to_dealloc_id_p = new_id; // save new id for later delete
1852 }
1853 return id;
1854 }
1857 // Common code to get the jmethodID cache length and the jmethodID
1858 // value at index idnum if there is one.
1859 //
1860 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1861 size_t idnum, size_t *length_p, jmethodID* id_p) {
1862 assert(cache != NULL, "sanity check");
1863 assert(length_p != NULL, "sanity check");
1864 assert(id_p != NULL, "sanity check");
1866 // cache size is stored in element[0], other elements offset by one
1867 *length_p = (size_t)cache[0];
1868 if (*length_p <= idnum) { // cache is too short
1869 *id_p = NULL;
1870 } else {
1871 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1872 }
1873 }
1876 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1877 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1878 size_t idnum = (size_t)method->method_idnum();
1879 jmethodID* jmeths = methods_jmethod_ids_acquire();
1880 size_t length; // length assigned as debugging crumb
1881 jmethodID id = NULL;
1882 if (jmeths != NULL && // If there is a cache
1883 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1884 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1885 }
1886 return id;
1887 }
1889 int nmethodBucket::decrement() {
1890 return Atomic::add(-1, (volatile int *)&_count);
1891 }
1893 //
1894 // Walk the list of dependent nmethods searching for nmethods which
1895 // are dependent on the changes that were passed in and mark them for
1896 // deoptimization. Returns the number of nmethods found.
1897 //
1898 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1899 assert_locked_or_safepoint(CodeCache_lock);
1900 int found = 0;
1901 nmethodBucket* b = _dependencies;
1902 while (b != NULL) {
1903 nmethod* nm = b->get_nmethod();
1904 // since dependencies aren't removed until an nmethod becomes a zombie,
1905 // the dependency list may contain nmethods which aren't alive.
1906 if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1907 if (TraceDependencies) {
1908 ResourceMark rm;
1909 tty->print_cr("Marked for deoptimization");
1910 tty->print_cr(" context = %s", this->external_name());
1911 changes.print();
1912 nm->print();
1913 nm->print_dependencies();
1914 }
1915 nm->mark_for_deoptimization();
1916 found++;
1917 }
1918 b = b->next();
1919 }
1920 return found;
1921 }
1923 void InstanceKlass::clean_dependent_nmethods() {
1924 assert_locked_or_safepoint(CodeCache_lock);
1926 if (has_unloaded_dependent()) {
1927 nmethodBucket* b = _dependencies;
1928 nmethodBucket* last = NULL;
1929 while (b != NULL) {
1930 assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
1932 nmethodBucket* next = b->next();
1934 if (b->count() == 0) {
1935 if (last == NULL) {
1936 _dependencies = next;
1937 } else {
1938 last->set_next(next);
1939 }
1940 delete b;
1941 // last stays the same.
1942 } else {
1943 last = b;
1944 }
1946 b = next;
1947 }
1948 set_has_unloaded_dependent(false);
1949 }
1950 #ifdef ASSERT
1951 else {
1952 // Verification
1953 for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) {
1954 assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
1955 assert(b->count() != 0, "empty buckets need to be cleaned");
1956 }
1957 }
1958 #endif
1959 }
1961 //
1962 // Add an nmethodBucket to the list of dependencies for this nmethod.
1963 // It's possible that an nmethod has multiple dependencies on this klass
1964 // so a count is kept for each bucket to guarantee that creation and
1965 // deletion of dependencies is consistent.
1966 //
1967 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1968 assert_locked_or_safepoint(CodeCache_lock);
1969 nmethodBucket* b = _dependencies;
1970 nmethodBucket* last = NULL;
1971 while (b != NULL) {
1972 if (nm == b->get_nmethod()) {
1973 b->increment();
1974 return;
1975 }
1976 b = b->next();
1977 }
1978 _dependencies = new nmethodBucket(nm, _dependencies);
1979 }
1982 //
1983 // Decrement count of the nmethod in the dependency list and remove
1984 // the bucket competely when the count goes to 0. This method must
1985 // find a corresponding bucket otherwise there's a bug in the
1986 // recording of dependecies.
1987 //
1988 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1989 assert_locked_or_safepoint(CodeCache_lock);
1990 nmethodBucket* b = _dependencies;
1991 nmethodBucket* last = NULL;
1992 while (b != NULL) {
1993 if (nm == b->get_nmethod()) {
1994 int val = b->decrement();
1995 guarantee(val >= 0, err_msg("Underflow: %d", val));
1996 if (val == 0) {
1997 if (delete_immediately) {
1998 if (last == NULL) {
1999 _dependencies = b->next();
2000 } else {
2001 last->set_next(b->next());
2002 }
2003 delete b;
2004 } else {
2005 // The deletion of this entry is deferred until a later, potentially parallel GC phase.
2006 set_has_unloaded_dependent(true);
2007 }
2008 }
2009 return;
2010 }
2011 last = b;
2012 b = b->next();
2013 }
2014 #ifdef ASSERT
2015 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
2016 nm->print();
2017 #endif // ASSERT
2018 ShouldNotReachHere();
2019 }
2022 #ifndef PRODUCT
2023 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2024 nmethodBucket* b = _dependencies;
2025 int idx = 0;
2026 while (b != NULL) {
2027 nmethod* nm = b->get_nmethod();
2028 tty->print("[%d] count=%d { ", idx++, b->count());
2029 if (!verbose) {
2030 nm->print_on(tty, "nmethod");
2031 tty->print_cr(" } ");
2032 } else {
2033 nm->print();
2034 nm->print_dependencies();
2035 tty->print_cr("--- } ");
2036 }
2037 b = b->next();
2038 }
2039 }
2042 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2043 nmethodBucket* b = _dependencies;
2044 while (b != NULL) {
2045 if (nm == b->get_nmethod()) {
2046 #ifdef ASSERT
2047 int count = b->count();
2048 assert(count >= 0, err_msg("count shouldn't be negative: %d", count));
2049 #endif
2050 return true;
2051 }
2052 b = b->next();
2053 }
2054 return false;
2055 }
2056 #endif //PRODUCT
2059 // Garbage collection
2061 #ifdef ASSERT
2062 template <class T> void assert_is_in(T *p) {
2063 T heap_oop = oopDesc::load_heap_oop(p);
2064 if (!oopDesc::is_null(heap_oop)) {
2065 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
2066 assert(Universe::heap()->is_in(o), "should be in heap");
2067 }
2068 }
2069 template <class T> void assert_is_in_closed_subset(T *p) {
2070 T heap_oop = oopDesc::load_heap_oop(p);
2071 if (!oopDesc::is_null(heap_oop)) {
2072 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
2073 assert(Universe::heap()->is_in_closed_subset(o),
2074 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
2075 }
2076 }
2077 template <class T> void assert_is_in_reserved(T *p) {
2078 T heap_oop = oopDesc::load_heap_oop(p);
2079 if (!oopDesc::is_null(heap_oop)) {
2080 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
2081 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
2082 }
2083 }
2084 template <class T> void assert_nothing(T *p) {}
2086 #else
2087 template <class T> void assert_is_in(T *p) {}
2088 template <class T> void assert_is_in_closed_subset(T *p) {}
2089 template <class T> void assert_is_in_reserved(T *p) {}
2090 template <class T> void assert_nothing(T *p) {}
2091 #endif // ASSERT
2093 //
2094 // Macros that iterate over areas of oops which are specialized on type of
2095 // oop pointer either narrow or wide, depending on UseCompressedOops
2096 //
2097 // Parameters are:
2098 // T - type of oop to point to (either oop or narrowOop)
2099 // start_p - starting pointer for region to iterate over
2100 // count - number of oops or narrowOops to iterate over
2101 // do_oop - action to perform on each oop (it's arbitrary C code which
2102 // makes it more efficient to put in a macro rather than making
2103 // it a template function)
2104 // assert_fn - assert function which is template function because performance
2105 // doesn't matter when enabled.
2106 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
2107 T, start_p, count, do_oop, \
2108 assert_fn) \
2109 { \
2110 T* p = (T*)(start_p); \
2111 T* const end = p + (count); \
2112 while (p < end) { \
2113 (assert_fn)(p); \
2114 do_oop; \
2115 ++p; \
2116 } \
2117 }
2119 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
2120 T, start_p, count, do_oop, \
2121 assert_fn) \
2122 { \
2123 T* const start = (T*)(start_p); \
2124 T* p = start + (count); \
2125 while (start < p) { \
2126 --p; \
2127 (assert_fn)(p); \
2128 do_oop; \
2129 } \
2130 }
2132 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
2133 T, start_p, count, low, high, \
2134 do_oop, assert_fn) \
2135 { \
2136 T* const l = (T*)(low); \
2137 T* const h = (T*)(high); \
2138 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
2139 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
2140 "bounded region must be properly aligned"); \
2141 T* p = (T*)(start_p); \
2142 T* end = p + (count); \
2143 if (p < l) p = l; \
2144 if (end > h) end = h; \
2145 while (p < end) { \
2146 (assert_fn)(p); \
2147 do_oop; \
2148 ++p; \
2149 } \
2150 }
2153 // The following macros call specialized macros, passing either oop or
2154 // narrowOop as the specialization type. These test the UseCompressedOops
2155 // flag.
2156 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
2157 { \
2158 /* Compute oopmap block range. The common case \
2159 is nonstatic_oop_map_size == 1. */ \
2160 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2161 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2162 if (UseCompressedOops) { \
2163 while (map < end_map) { \
2164 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
2165 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2166 do_oop, assert_fn) \
2167 ++map; \
2168 } \
2169 } else { \
2170 while (map < end_map) { \
2171 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
2172 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2173 do_oop, assert_fn) \
2174 ++map; \
2175 } \
2176 } \
2177 }
2179 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
2180 { \
2181 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
2182 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
2183 if (UseCompressedOops) { \
2184 while (start_map < map) { \
2185 --map; \
2186 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
2187 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2188 do_oop, assert_fn) \
2189 } \
2190 } else { \
2191 while (start_map < map) { \
2192 --map; \
2193 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
2194 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2195 do_oop, assert_fn) \
2196 } \
2197 } \
2198 }
2200 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
2201 assert_fn) \
2202 { \
2203 /* Compute oopmap block range. The common case is \
2204 nonstatic_oop_map_size == 1, so we accept the \
2205 usually non-existent extra overhead of examining \
2206 all the maps. */ \
2207 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2208 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2209 if (UseCompressedOops) { \
2210 while (map < end_map) { \
2211 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
2212 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2213 low, high, \
2214 do_oop, assert_fn) \
2215 ++map; \
2216 } \
2217 } else { \
2218 while (map < end_map) { \
2219 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2220 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2221 low, high, \
2222 do_oop, assert_fn) \
2223 ++map; \
2224 } \
2225 } \
2226 }
2228 void InstanceKlass::oop_follow_contents(oop obj) {
2229 assert(obj != NULL, "can't follow the content of NULL object");
2230 MarkSweep::follow_klass(obj->klass());
2231 InstanceKlass_OOP_MAP_ITERATE( \
2232 obj, \
2233 MarkSweep::mark_and_push(p), \
2234 assert_is_in_closed_subset)
2235 }
2237 #if INCLUDE_ALL_GCS
2238 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2239 oop obj) {
2240 assert(obj != NULL, "can't follow the content of NULL object");
2241 PSParallelCompact::follow_klass(cm, obj->klass());
2242 // Only mark the header and let the scan of the meta-data mark
2243 // everything else.
2244 InstanceKlass_OOP_MAP_ITERATE( \
2245 obj, \
2246 PSParallelCompact::mark_and_push(cm, p), \
2247 assert_is_in)
2248 }
2249 #endif // INCLUDE_ALL_GCS
2251 // closure's do_metadata() method dictates whether the given closure should be
2252 // applied to the klass ptr in the object header.
2254 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2255 \
2256 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2257 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2258 /* header */ \
2259 if_do_metadata_checked(closure, nv_suffix) { \
2260 closure->do_klass##nv_suffix(obj->klass()); \
2261 } \
2262 InstanceKlass_OOP_MAP_ITERATE( \
2263 obj, \
2264 SpecializationStats:: \
2265 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2266 (closure)->do_oop##nv_suffix(p), \
2267 assert_is_in_closed_subset) \
2268 return size_helper(); \
2269 }
2271 #if INCLUDE_ALL_GCS
2272 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2273 \
2274 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2275 OopClosureType* closure) { \
2276 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2277 \
2278 assert_should_ignore_metadata(closure, nv_suffix); \
2279 \
2280 /* instance variables */ \
2281 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2282 obj, \
2283 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2284 (closure)->do_oop##nv_suffix(p), \
2285 assert_is_in_closed_subset) \
2286 return size_helper(); \
2287 }
2288 #endif // INCLUDE_ALL_GCS
2290 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2291 \
2292 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2293 OopClosureType* closure, \
2294 MemRegion mr) { \
2295 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2296 if_do_metadata_checked(closure, nv_suffix) { \
2297 if (mr.contains(obj)) { \
2298 closure->do_klass##nv_suffix(obj->klass()); \
2299 } \
2300 } \
2301 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2302 obj, mr.start(), mr.end(), \
2303 (closure)->do_oop##nv_suffix(p), \
2304 assert_is_in_closed_subset) \
2305 return size_helper(); \
2306 }
2308 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2309 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2310 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2311 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2312 #if INCLUDE_ALL_GCS
2313 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2314 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2315 #endif // INCLUDE_ALL_GCS
2317 int InstanceKlass::oop_adjust_pointers(oop obj) {
2318 int size = size_helper();
2319 InstanceKlass_OOP_MAP_ITERATE( \
2320 obj, \
2321 MarkSweep::adjust_pointer(p), \
2322 assert_is_in)
2323 return size;
2324 }
2326 #if INCLUDE_ALL_GCS
2327 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2328 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2329 obj, \
2330 if (PSScavenge::should_scavenge(p)) { \
2331 pm->claim_or_forward_depth(p); \
2332 }, \
2333 assert_nothing )
2334 }
2336 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2337 int size = size_helper();
2338 InstanceKlass_OOP_MAP_ITERATE( \
2339 obj, \
2340 PSParallelCompact::adjust_pointer(p), \
2341 assert_is_in)
2342 return size;
2343 }
2345 #endif // INCLUDE_ALL_GCS
2347 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2348 clean_implementors_list(is_alive);
2349 clean_method_data(is_alive);
2351 clean_dependent_nmethods();
2352 }
2354 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2355 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2356 if (is_interface()) {
2357 if (ClassUnloading) {
2358 Klass* impl = implementor();
2359 if (impl != NULL) {
2360 if (!impl->is_loader_alive(is_alive)) {
2361 // remove this guy
2362 Klass** klass = adr_implementor();
2363 assert(klass != NULL, "null klass");
2364 if (klass != NULL) {
2365 *klass = NULL;
2366 }
2367 }
2368 }
2369 }
2370 }
2371 }
2373 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2374 for (int m = 0; m < methods()->length(); m++) {
2375 MethodData* mdo = methods()->at(m)->method_data();
2376 if (mdo != NULL) {
2377 mdo->clean_method_data(is_alive);
2378 }
2379 }
2380 }
2383 static void remove_unshareable_in_class(Klass* k) {
2384 // remove klass's unshareable info
2385 k->remove_unshareable_info();
2386 }
2388 void InstanceKlass::remove_unshareable_info() {
2389 Klass::remove_unshareable_info();
2390 // Unlink the class
2391 if (is_linked()) {
2392 unlink_class();
2393 }
2394 init_implementor();
2396 constants()->remove_unshareable_info();
2398 for (int i = 0; i < methods()->length(); i++) {
2399 Method* m = methods()->at(i);
2400 m->remove_unshareable_info();
2401 }
2403 // do array classes also.
2404 array_klasses_do(remove_unshareable_in_class);
2405 }
2407 static void restore_unshareable_in_class(Klass* k, TRAPS) {
2408 // Array classes have null protection domain.
2409 // --> see ArrayKlass::complete_create_array_klass()
2410 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2411 }
2413 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2414 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2415 instanceKlassHandle ik(THREAD, this);
2417 Array<Method*>* methods = ik->methods();
2418 int num_methods = methods->length();
2419 for (int index2 = 0; index2 < num_methods; ++index2) {
2420 methodHandle m(THREAD, methods->at(index2));
2421 m->restore_unshareable_info(CHECK);
2422 }
2423 if (JvmtiExport::has_redefined_a_class()) {
2424 // Reinitialize vtable because RedefineClasses may have changed some
2425 // entries in this vtable for super classes so the CDS vtable might
2426 // point to old or obsolete entries. RedefineClasses doesn't fix up
2427 // vtables in the shared system dictionary, only the main one.
2428 // It also redefines the itable too so fix that too.
2429 ResourceMark rm(THREAD);
2430 ik->vtable()->initialize_vtable(false, CHECK);
2431 ik->itable()->initialize_itable(false, CHECK);
2432 }
2434 // restore constant pool resolved references
2435 ik->constants()->restore_unshareable_info(CHECK);
2437 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2438 }
2440 // returns true IFF is_in_error_state() has been changed as a result of this call.
2441 bool InstanceKlass::check_sharing_error_state() {
2442 assert(DumpSharedSpaces, "should only be called during dumping");
2443 bool old_state = is_in_error_state();
2445 if (!is_in_error_state()) {
2446 bool bad = false;
2447 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2448 if (sup->is_in_error_state()) {
2449 bad = true;
2450 break;
2451 }
2452 }
2453 if (!bad) {
2454 Array<Klass*>* interfaces = transitive_interfaces();
2455 for (int i = 0; i < interfaces->length(); i++) {
2456 Klass* iface = interfaces->at(i);
2457 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2458 bad = true;
2459 break;
2460 }
2461 }
2462 }
2464 if (bad) {
2465 set_in_error_state();
2466 }
2467 }
2469 return (old_state != is_in_error_state());
2470 }
2472 static void clear_all_breakpoints(Method* m) {
2473 m->clear_all_breakpoints();
2474 }
2477 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2478 // notify the debugger
2479 if (JvmtiExport::should_post_class_unload()) {
2480 JvmtiExport::post_class_unload(ik);
2481 }
2483 // notify ClassLoadingService of class unload
2484 ClassLoadingService::notify_class_unloaded(ik);
2485 }
2487 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2488 // Clean up C heap
2489 ik->release_C_heap_structures();
2490 ik->constants()->release_C_heap_structures();
2491 }
2493 void InstanceKlass::release_C_heap_structures() {
2495 // Can't release the constant pool here because the constant pool can be
2496 // deallocated separately from the InstanceKlass for default methods and
2497 // redefine classes.
2499 // Deallocate oop map cache
2500 if (_oop_map_cache != NULL) {
2501 delete _oop_map_cache;
2502 _oop_map_cache = NULL;
2503 }
2505 // Deallocate JNI identifiers for jfieldIDs
2506 JNIid::deallocate(jni_ids());
2507 set_jni_ids(NULL);
2509 jmethodID* jmeths = methods_jmethod_ids_acquire();
2510 if (jmeths != (jmethodID*)NULL) {
2511 release_set_methods_jmethod_ids(NULL);
2512 FreeHeap(jmeths);
2513 }
2515 // Deallocate MemberNameTable
2516 {
2517 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2518 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2519 MemberNameTable* mnt = member_names();
2520 if (mnt != NULL) {
2521 delete mnt;
2522 set_member_names(NULL);
2523 }
2524 }
2526 // release dependencies
2527 nmethodBucket* b = _dependencies;
2528 _dependencies = NULL;
2529 while (b != NULL) {
2530 nmethodBucket* next = b->next();
2531 delete b;
2532 b = next;
2533 }
2535 // Deallocate breakpoint records
2536 if (breakpoints() != 0x0) {
2537 methods_do(clear_all_breakpoints);
2538 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2539 }
2541 // deallocate information about previous versions
2542 if (_previous_versions != NULL) {
2543 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2544 PreviousVersionNode * pv_node = _previous_versions->at(i);
2545 delete pv_node;
2546 }
2547 delete _previous_versions;
2548 _previous_versions = NULL;
2549 }
2551 // deallocate the cached class file
2552 if (_cached_class_file != NULL) {
2553 os::free(_cached_class_file, mtClass);
2554 _cached_class_file = NULL;
2555 }
2557 // Decrement symbol reference counts associated with the unloaded class.
2558 if (_name != NULL) _name->decrement_refcount();
2559 // unreference array name derived from this class name (arrays of an unloaded
2560 // class can't be referenced anymore).
2561 if (_array_name != NULL) _array_name->decrement_refcount();
2562 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2564 assert(_total_instanceKlass_count >= 1, "Sanity check");
2565 Atomic::dec(&_total_instanceKlass_count);
2566 }
2568 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2569 if (array == NULL) {
2570 _source_debug_extension = NULL;
2571 } else {
2572 // Adding one to the attribute length in order to store a null terminator
2573 // character could cause an overflow because the attribute length is
2574 // already coded with an u4 in the classfile, but in practice, it's
2575 // unlikely to happen.
2576 assert((length+1) > length, "Overflow checking");
2577 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2578 for (int i = 0; i < length; i++) {
2579 sde[i] = array[i];
2580 }
2581 sde[length] = '\0';
2582 _source_debug_extension = sde;
2583 }
2584 }
2586 address InstanceKlass::static_field_addr(int offset) {
2587 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2588 }
2591 const char* InstanceKlass::signature_name() const {
2592 int hash_len = 0;
2593 char hash_buf[40];
2595 // If this is an anonymous class, append a hash to make the name unique
2596 if (is_anonymous()) {
2597 assert(EnableInvokeDynamic, "EnableInvokeDynamic was not set.");
2598 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2599 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
2600 hash_len = (int)strlen(hash_buf);
2601 }
2603 // Get the internal name as a c string
2604 const char* src = (const char*) (name()->as_C_string());
2605 const int src_length = (int)strlen(src);
2607 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2609 // Add L as type indicator
2610 int dest_index = 0;
2611 dest[dest_index++] = 'L';
2613 // Add the actual class name
2614 for (int src_index = 0; src_index < src_length; ) {
2615 dest[dest_index++] = src[src_index++];
2616 }
2618 // If we have a hash, append it
2619 for (int hash_index = 0; hash_index < hash_len; ) {
2620 dest[dest_index++] = hash_buf[hash_index++];
2621 }
2623 // Add the semicolon and the NULL
2624 dest[dest_index++] = ';';
2625 dest[dest_index] = '\0';
2626 return dest;
2627 }
2629 // different verisons of is_same_class_package
2630 bool InstanceKlass::is_same_class_package(Klass* class2) {
2631 Klass* class1 = this;
2632 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2633 Symbol* classname1 = class1->name();
2635 if (class2->oop_is_objArray()) {
2636 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2637 }
2638 oop classloader2;
2639 if (class2->oop_is_instance()) {
2640 classloader2 = InstanceKlass::cast(class2)->class_loader();
2641 } else {
2642 assert(class2->oop_is_typeArray(), "should be type array");
2643 classloader2 = NULL;
2644 }
2645 Symbol* classname2 = class2->name();
2647 return InstanceKlass::is_same_class_package(classloader1, classname1,
2648 classloader2, classname2);
2649 }
2651 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2652 Klass* class1 = this;
2653 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2654 Symbol* classname1 = class1->name();
2656 return InstanceKlass::is_same_class_package(classloader1, classname1,
2657 classloader2, classname2);
2658 }
2660 // return true if two classes are in the same package, classloader
2661 // and classname information is enough to determine a class's package
2662 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2663 oop class_loader2, Symbol* class_name2) {
2664 if (class_loader1 != class_loader2) {
2665 return false;
2666 } else if (class_name1 == class_name2) {
2667 return true; // skip painful bytewise comparison
2668 } else {
2669 ResourceMark rm;
2671 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2672 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2673 // Otherwise, we just compare jbyte values between the strings.
2674 const jbyte *name1 = class_name1->base();
2675 const jbyte *name2 = class_name2->base();
2677 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2678 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2680 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2681 // One of the two doesn't have a package. Only return true
2682 // if the other one also doesn't have a package.
2683 return last_slash1 == last_slash2;
2684 } else {
2685 // Skip over '['s
2686 if (*name1 == '[') {
2687 do {
2688 name1++;
2689 } while (*name1 == '[');
2690 if (*name1 != 'L') {
2691 // Something is terribly wrong. Shouldn't be here.
2692 return false;
2693 }
2694 }
2695 if (*name2 == '[') {
2696 do {
2697 name2++;
2698 } while (*name2 == '[');
2699 if (*name2 != 'L') {
2700 // Something is terribly wrong. Shouldn't be here.
2701 return false;
2702 }
2703 }
2705 // Check that package part is identical
2706 int length1 = last_slash1 - name1;
2707 int length2 = last_slash2 - name2;
2709 return UTF8::equal(name1, length1, name2, length2);
2710 }
2711 }
2712 }
2714 // Returns true iff super_method can be overridden by a method in targetclassname
2715 // See JSL 3rd edition 8.4.6.1
2716 // Assumes name-signature match
2717 // "this" is InstanceKlass of super_method which must exist
2718 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2719 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2720 // Private methods can not be overridden
2721 if (super_method->is_private()) {
2722 return false;
2723 }
2724 // If super method is accessible, then override
2725 if ((super_method->is_protected()) ||
2726 (super_method->is_public())) {
2727 return true;
2728 }
2729 // Package-private methods are not inherited outside of package
2730 assert(super_method->is_package_private(), "must be package private");
2731 return(is_same_class_package(targetclassloader(), targetclassname));
2732 }
2734 /* defined for now in jvm.cpp, for historical reasons *--
2735 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2736 Symbol*& simple_name_result, TRAPS) {
2737 ...
2738 }
2739 */
2741 // tell if two classes have the same enclosing class (at package level)
2742 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2743 Klass* class2_oop, TRAPS) {
2744 if (class2_oop == class1()) return true;
2745 if (!class2_oop->oop_is_instance()) return false;
2746 instanceKlassHandle class2(THREAD, class2_oop);
2748 // must be in same package before we try anything else
2749 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2750 return false;
2752 // As long as there is an outer1.getEnclosingClass,
2753 // shift the search outward.
2754 instanceKlassHandle outer1 = class1;
2755 for (;;) {
2756 // As we walk along, look for equalities between outer1 and class2.
2757 // Eventually, the walks will terminate as outer1 stops
2758 // at the top-level class around the original class.
2759 bool ignore_inner_is_member;
2760 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2761 CHECK_false);
2762 if (next == NULL) break;
2763 if (next == class2()) return true;
2764 outer1 = instanceKlassHandle(THREAD, next);
2765 }
2767 // Now do the same for class2.
2768 instanceKlassHandle outer2 = class2;
2769 for (;;) {
2770 bool ignore_inner_is_member;
2771 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2772 CHECK_false);
2773 if (next == NULL) break;
2774 // Might as well check the new outer against all available values.
2775 if (next == class1()) return true;
2776 if (next == outer1()) return true;
2777 outer2 = instanceKlassHandle(THREAD, next);
2778 }
2780 // If by this point we have not found an equality between the
2781 // two classes, we know they are in separate package members.
2782 return false;
2783 }
2786 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2787 jint access = access_flags().as_int();
2789 // But check if it happens to be member class.
2790 instanceKlassHandle ik(THREAD, this);
2791 InnerClassesIterator iter(ik);
2792 for (; !iter.done(); iter.next()) {
2793 int ioff = iter.inner_class_info_index();
2794 // Inner class attribute can be zero, skip it.
2795 // Strange but true: JVM spec. allows null inner class refs.
2796 if (ioff == 0) continue;
2798 // only look at classes that are already loaded
2799 // since we are looking for the flags for our self.
2800 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2801 if ((ik->name() == inner_name)) {
2802 // This is really a member class.
2803 access = iter.inner_access_flags();
2804 break;
2805 }
2806 }
2807 // Remember to strip ACC_SUPER bit
2808 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2809 }
2811 jint InstanceKlass::jvmti_class_status() const {
2812 jint result = 0;
2814 if (is_linked()) {
2815 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2816 }
2818 if (is_initialized()) {
2819 assert(is_linked(), "Class status is not consistent");
2820 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2821 }
2822 if (is_in_error_state()) {
2823 result |= JVMTI_CLASS_STATUS_ERROR;
2824 }
2825 return result;
2826 }
2828 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2829 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2830 int method_table_offset_in_words = ioe->offset()/wordSize;
2831 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2832 / itableOffsetEntry::size();
2834 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2835 // If the interface isn't implemented by the receiver class,
2836 // the VM should throw IncompatibleClassChangeError.
2837 if (cnt >= nof_interfaces) {
2838 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2839 }
2841 Klass* ik = ioe->interface_klass();
2842 if (ik == holder) break;
2843 }
2845 itableMethodEntry* ime = ioe->first_method_entry(this);
2846 Method* m = ime[index].method();
2847 if (m == NULL) {
2848 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2849 }
2850 return m;
2851 }
2854 #if INCLUDE_JVMTI
2855 // update default_methods for redefineclasses for methods that are
2856 // not yet in the vtable due to concurrent subclass define and superinterface
2857 // redefinition
2858 // Note: those in the vtable, should have been updated via adjust_method_entries
2859 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2860 // search the default_methods for uses of either obsolete or EMCP methods
2861 if (default_methods() != NULL) {
2862 for (int index = 0; index < default_methods()->length(); index ++) {
2863 Method* old_method = default_methods()->at(index);
2864 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2865 continue; // skip uninteresting entries
2866 }
2867 assert(!old_method->is_deleted(), "default methods may not be deleted");
2869 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2871 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2872 assert(old_method != new_method, "sanity check");
2874 default_methods()->at_put(index, new_method);
2875 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2876 if (!(*trace_name_printed)) {
2877 // RC_TRACE_MESG macro has an embedded ResourceMark
2878 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2879 external_name(),
2880 old_method->method_holder()->external_name()));
2881 *trace_name_printed = true;
2882 }
2883 RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2884 new_method->name()->as_C_string(),
2885 new_method->signature()->as_C_string()));
2886 }
2887 }
2888 }
2889 }
2890 #endif // INCLUDE_JVMTI
2892 // On-stack replacement stuff
2893 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2894 // only one compilation can be active
2895 NEEDS_CLEANUP
2896 // This is a short non-blocking critical region, so the no safepoint check is ok.
2897 OsrList_lock->lock_without_safepoint_check();
2898 assert(n->is_osr_method(), "wrong kind of nmethod");
2899 n->set_osr_link(osr_nmethods_head());
2900 set_osr_nmethods_head(n);
2901 // Raise the highest osr level if necessary
2902 if (TieredCompilation) {
2903 Method* m = n->method();
2904 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2905 }
2906 // Remember to unlock again
2907 OsrList_lock->unlock();
2909 // Get rid of the osr methods for the same bci that have lower levels.
2910 if (TieredCompilation) {
2911 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2912 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2913 if (inv != NULL && inv->is_in_use()) {
2914 inv->make_not_entrant();
2915 }
2916 }
2917 }
2918 }
2921 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2922 // This is a short non-blocking critical region, so the no safepoint check is ok.
2923 OsrList_lock->lock_without_safepoint_check();
2924 assert(n->is_osr_method(), "wrong kind of nmethod");
2925 nmethod* last = NULL;
2926 nmethod* cur = osr_nmethods_head();
2927 int max_level = CompLevel_none; // Find the max comp level excluding n
2928 Method* m = n->method();
2929 // Search for match
2930 while(cur != NULL && cur != n) {
2931 if (TieredCompilation && m == cur->method()) {
2932 // Find max level before n
2933 max_level = MAX2(max_level, cur->comp_level());
2934 }
2935 last = cur;
2936 cur = cur->osr_link();
2937 }
2938 nmethod* next = NULL;
2939 if (cur == n) {
2940 next = cur->osr_link();
2941 if (last == NULL) {
2942 // Remove first element
2943 set_osr_nmethods_head(next);
2944 } else {
2945 last->set_osr_link(next);
2946 }
2947 }
2948 n->set_osr_link(NULL);
2949 if (TieredCompilation) {
2950 cur = next;
2951 while (cur != NULL) {
2952 // Find max level after n
2953 if (m == cur->method()) {
2954 max_level = MAX2(max_level, cur->comp_level());
2955 }
2956 cur = cur->osr_link();
2957 }
2958 m->set_highest_osr_comp_level(max_level);
2959 }
2960 // Remember to unlock again
2961 OsrList_lock->unlock();
2962 }
2964 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2965 // This is a short non-blocking critical region, so the no safepoint check is ok.
2966 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2967 nmethod* osr = osr_nmethods_head();
2968 int found = 0;
2969 while (osr != NULL) {
2970 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2971 if (osr->method() == m) {
2972 osr->mark_for_deoptimization();
2973 found++;
2974 }
2975 osr = osr->osr_link();
2976 }
2977 return found;
2978 }
2980 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2981 // This is a short non-blocking critical region, so the no safepoint check is ok.
2982 OsrList_lock->lock_without_safepoint_check();
2983 nmethod* osr = osr_nmethods_head();
2984 nmethod* best = NULL;
2985 while (osr != NULL) {
2986 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2987 // There can be a time when a c1 osr method exists but we are waiting
2988 // for a c2 version. When c2 completes its osr nmethod we will trash
2989 // the c1 version and only be able to find the c2 version. However
2990 // while we overflow in the c1 code at back branches we don't want to
2991 // try and switch to the same code as we are already running
2993 if (osr->method() == m &&
2994 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2995 if (match_level) {
2996 if (osr->comp_level() == comp_level) {
2997 // Found a match - return it.
2998 OsrList_lock->unlock();
2999 return osr;
3000 }
3001 } else {
3002 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3003 if (osr->comp_level() == CompLevel_highest_tier) {
3004 // Found the best possible - return it.
3005 OsrList_lock->unlock();
3006 return osr;
3007 }
3008 best = osr;
3009 }
3010 }
3011 }
3012 osr = osr->osr_link();
3013 }
3014 OsrList_lock->unlock();
3015 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3016 return best;
3017 }
3018 return NULL;
3019 }
3021 oop InstanceKlass::add_member_name(Handle mem_name, bool intern) {
3022 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
3023 MutexLocker ml(MemberNameTable_lock);
3024 DEBUG_ONLY(No_Safepoint_Verifier nsv);
3026 // Check if method has been redefined while taking out MemberNameTable_lock, if so
3027 // return false. We cannot cache obsolete methods. They will crash when the function
3028 // is called!
3029 Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
3030 if (method->is_obsolete()) {
3031 return NULL;
3032 } else if (method->is_old()) {
3033 // Replace method with redefined version
3034 java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
3035 }
3037 if (_member_names == NULL) {
3038 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
3039 }
3040 if (intern) {
3041 return _member_names->find_or_add_member_name(mem_name_wref);
3042 } else {
3043 return _member_names->add_member_name(mem_name_wref);
3044 }
3045 }
3047 // -----------------------------------------------------------------------------------------------------
3048 // Printing
3050 #ifndef PRODUCT
3052 #define BULLET " - "
3054 static const char* state_names[] = {
3055 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3056 };
3058 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3059 for (int i = 0; i < len; i++) {
3060 intptr_t e = start[i];
3061 st->print("%d : " INTPTR_FORMAT, i, e);
3062 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3063 st->print(" ");
3064 ((Metadata*)e)->print_value_on(st);
3065 }
3066 st->cr();
3067 }
3068 }
3070 void InstanceKlass::print_on(outputStream* st) const {
3071 assert(is_klass(), "must be klass");
3072 Klass::print_on(st);
3074 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3075 st->print(BULLET"klass size: %d", size()); st->cr();
3076 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3077 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3078 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3079 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3080 st->print(BULLET"sub: ");
3081 Klass* sub = subklass();
3082 int n;
3083 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3084 if (n < MaxSubklassPrintSize) {
3085 sub->print_value_on(st);
3086 st->print(" ");
3087 }
3088 }
3089 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
3090 st->cr();
3092 if (is_interface()) {
3093 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3094 if (nof_implementors() == 1) {
3095 st->print_cr(BULLET"implementor: ");
3096 st->print(" ");
3097 implementor()->print_value_on(st);
3098 st->cr();
3099 }
3100 }
3102 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3103 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3104 if (Verbose || WizardMode) {
3105 Array<Method*>* method_array = methods();
3106 for (int i = 0; i < method_array->length(); i++) {
3107 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3108 }
3109 }
3110 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3111 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3112 if (Verbose && default_methods() != NULL) {
3113 Array<Method*>* method_array = default_methods();
3114 for (int i = 0; i < method_array->length(); i++) {
3115 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3116 }
3117 }
3118 if (default_vtable_indices() != NULL) {
3119 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3120 }
3121 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3122 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3123 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3124 if (class_loader_data() != NULL) {
3125 st->print(BULLET"class loader data: ");
3126 class_loader_data()->print_value_on(st);
3127 st->cr();
3128 }
3129 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3130 if (source_file_name() != NULL) {
3131 st->print(BULLET"source file: ");
3132 source_file_name()->print_value_on(st);
3133 st->cr();
3134 }
3135 if (source_debug_extension() != NULL) {
3136 st->print(BULLET"source debug extension: ");
3137 st->print("%s", source_debug_extension());
3138 st->cr();
3139 }
3140 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3141 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3142 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3143 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3144 {
3145 bool have_pv = false;
3146 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
3147 for (PreviousVersionNode * pv_node = pvw.next_previous_version();
3148 pv_node != NULL; pv_node = pvw.next_previous_version()) {
3149 if (!have_pv)
3150 st->print(BULLET"previous version: ");
3151 have_pv = true;
3152 pv_node->prev_constant_pool()->print_value_on(st);
3153 }
3154 if (have_pv) st->cr();
3155 } // pvw is cleaned up
3157 if (generic_signature() != NULL) {
3158 st->print(BULLET"generic signature: ");
3159 generic_signature()->print_value_on(st);
3160 st->cr();
3161 }
3162 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3163 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3164 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
3165 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3166 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
3167 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3168 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3169 FieldPrinter print_static_field(st);
3170 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3171 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3172 FieldPrinter print_nonstatic_field(st);
3173 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
3175 st->print(BULLET"non-static oop maps: ");
3176 OopMapBlock* map = start_of_nonstatic_oop_maps();
3177 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3178 while (map < end_map) {
3179 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3180 map++;
3181 }
3182 st->cr();
3183 }
3185 #endif //PRODUCT
3187 void InstanceKlass::print_value_on(outputStream* st) const {
3188 assert(is_klass(), "must be klass");
3189 if (Verbose || WizardMode) access_flags().print_on(st);
3190 name()->print_value_on(st);
3191 }
3193 #ifndef PRODUCT
3195 void FieldPrinter::do_field(fieldDescriptor* fd) {
3196 _st->print(BULLET);
3197 if (_obj == NULL) {
3198 fd->print_on(_st);
3199 _st->cr();
3200 } else {
3201 fd->print_on_for(_st, _obj);
3202 _st->cr();
3203 }
3204 }
3207 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3208 Klass::oop_print_on(obj, st);
3210 if (this == SystemDictionary::String_klass()) {
3211 typeArrayOop value = java_lang_String::value(obj);
3212 juint offset = java_lang_String::offset(obj);
3213 juint length = java_lang_String::length(obj);
3214 if (value != NULL &&
3215 value->is_typeArray() &&
3216 offset <= (juint) value->length() &&
3217 offset + length <= (juint) value->length()) {
3218 st->print(BULLET"string: ");
3219 java_lang_String::print(obj, st);
3220 st->cr();
3221 if (!WizardMode) return; // that is enough
3222 }
3223 }
3225 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3226 FieldPrinter print_field(st, obj);
3227 do_nonstatic_fields(&print_field);
3229 if (this == SystemDictionary::Class_klass()) {
3230 st->print(BULLET"signature: ");
3231 java_lang_Class::print_signature(obj, st);
3232 st->cr();
3233 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3234 st->print(BULLET"fake entry for mirror: ");
3235 mirrored_klass->print_value_on_maybe_null(st);
3236 st->cr();
3237 Klass* array_klass = java_lang_Class::array_klass(obj);
3238 st->print(BULLET"fake entry for array: ");
3239 array_klass->print_value_on_maybe_null(st);
3240 st->cr();
3241 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3242 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3243 Klass* real_klass = java_lang_Class::as_Klass(obj);
3244 if (real_klass != NULL && real_klass->oop_is_instance()) {
3245 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3246 }
3247 } else if (this == SystemDictionary::MethodType_klass()) {
3248 st->print(BULLET"signature: ");
3249 java_lang_invoke_MethodType::print_signature(obj, st);
3250 st->cr();
3251 }
3252 }
3254 #endif //PRODUCT
3256 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3257 st->print("a ");
3258 name()->print_value_on(st);
3259 obj->print_address_on(st);
3260 if (this == SystemDictionary::String_klass()
3261 && java_lang_String::value(obj) != NULL) {
3262 ResourceMark rm;
3263 int len = java_lang_String::length(obj);
3264 int plen = (len < 24 ? len : 12);
3265 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3266 st->print(" = \"%s\"", str);
3267 if (len > plen)
3268 st->print("...[%d]", len);
3269 } else if (this == SystemDictionary::Class_klass()) {
3270 Klass* k = java_lang_Class::as_Klass(obj);
3271 st->print(" = ");
3272 if (k != NULL) {
3273 k->print_value_on(st);
3274 } else {
3275 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3276 st->print("%s", tname ? tname : "type?");
3277 }
3278 } else if (this == SystemDictionary::MethodType_klass()) {
3279 st->print(" = ");
3280 java_lang_invoke_MethodType::print_signature(obj, st);
3281 } else if (java_lang_boxing_object::is_instance(obj)) {
3282 st->print(" = ");
3283 java_lang_boxing_object::print(obj, st);
3284 } else if (this == SystemDictionary::LambdaForm_klass()) {
3285 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3286 if (vmentry != NULL) {
3287 st->print(" => ");
3288 vmentry->print_value_on(st);
3289 }
3290 } else if (this == SystemDictionary::MemberName_klass()) {
3291 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3292 if (vmtarget != NULL) {
3293 st->print(" = ");
3294 vmtarget->print_value_on(st);
3295 } else {
3296 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3297 st->print(".");
3298 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3299 }
3300 }
3301 }
3303 const char* InstanceKlass::internal_name() const {
3304 return external_name();
3305 }
3307 #if INCLUDE_SERVICES
3308 // Size Statistics
3309 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3310 Klass::collect_statistics(sz);
3312 sz->_inst_size = HeapWordSize * size_helper();
3313 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
3314 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
3315 sz->_nonstatic_oopmap_bytes = HeapWordSize *
3316 ((is_interface() || is_anonymous()) ?
3317 align_object_offset(nonstatic_oop_map_size()) :
3318 nonstatic_oop_map_size());
3320 int n = 0;
3321 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3322 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3323 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3324 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3325 n += (sz->_fields_bytes = sz->count_array(fields()));
3326 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3327 sz->_ro_bytes += n;
3329 const ConstantPool* cp = constants();
3330 if (cp) {
3331 cp->collect_statistics(sz);
3332 }
3334 const Annotations* anno = annotations();
3335 if (anno) {
3336 anno->collect_statistics(sz);
3337 }
3339 const Array<Method*>* methods_array = methods();
3340 if (methods()) {
3341 for (int i = 0; i < methods_array->length(); i++) {
3342 Method* method = methods_array->at(i);
3343 if (method) {
3344 sz->_method_count ++;
3345 method->collect_statistics(sz);
3346 }
3347 }
3348 }
3349 }
3350 #endif // INCLUDE_SERVICES
3352 // Verification
3354 class VerifyFieldClosure: public OopClosure {
3355 protected:
3356 template <class T> void do_oop_work(T* p) {
3357 oop obj = oopDesc::load_decode_heap_oop(p);
3358 if (!obj->is_oop_or_null()) {
3359 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
3360 Universe::print();
3361 guarantee(false, "boom");
3362 }
3363 }
3364 public:
3365 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3366 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3367 };
3369 void InstanceKlass::verify_on(outputStream* st) {
3370 #ifndef PRODUCT
3371 // Avoid redundant verifies, this really should be in product.
3372 if (_verify_count == Universe::verify_count()) return;
3373 _verify_count = Universe::verify_count();
3374 #endif
3376 // Verify Klass
3377 Klass::verify_on(st);
3379 // Verify that klass is present in ClassLoaderData
3380 guarantee(class_loader_data()->contains_klass(this),
3381 "this class isn't found in class loader data");
3383 // Verify vtables
3384 if (is_linked()) {
3385 ResourceMark rm;
3386 // $$$ This used to be done only for m/s collections. Doing it
3387 // always seemed a valid generalization. (DLD -- 6/00)
3388 vtable()->verify(st);
3389 }
3391 // Verify first subklass
3392 if (subklass_oop() != NULL) {
3393 guarantee(subklass_oop()->is_klass(), "should be klass");
3394 }
3396 // Verify siblings
3397 Klass* super = this->super();
3398 Klass* sib = next_sibling();
3399 if (sib != NULL) {
3400 if (sib == this) {
3401 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3402 }
3404 guarantee(sib->is_klass(), "should be klass");
3405 guarantee(sib->super() == super, "siblings should have same superklass");
3406 }
3408 // Verify implementor fields
3409 Klass* im = implementor();
3410 if (im != NULL) {
3411 guarantee(is_interface(), "only interfaces should have implementor set");
3412 guarantee(im->is_klass(), "should be klass");
3413 guarantee(!im->is_interface() || im == this,
3414 "implementors cannot be interfaces");
3415 }
3417 // Verify local interfaces
3418 if (local_interfaces()) {
3419 Array<Klass*>* local_interfaces = this->local_interfaces();
3420 for (int j = 0; j < local_interfaces->length(); j++) {
3421 Klass* e = local_interfaces->at(j);
3422 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3423 }
3424 }
3426 // Verify transitive interfaces
3427 if (transitive_interfaces() != NULL) {
3428 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3429 for (int j = 0; j < transitive_interfaces->length(); j++) {
3430 Klass* e = transitive_interfaces->at(j);
3431 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3432 }
3433 }
3435 // Verify methods
3436 if (methods() != NULL) {
3437 Array<Method*>* methods = this->methods();
3438 for (int j = 0; j < methods->length(); j++) {
3439 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3440 }
3441 for (int j = 0; j < methods->length() - 1; j++) {
3442 Method* m1 = methods->at(j);
3443 Method* m2 = methods->at(j + 1);
3444 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3445 }
3446 }
3448 // Verify method ordering
3449 if (method_ordering() != NULL) {
3450 Array<int>* method_ordering = this->method_ordering();
3451 int length = method_ordering->length();
3452 if (JvmtiExport::can_maintain_original_method_order() ||
3453 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3454 guarantee(length == methods()->length(), "invalid method ordering length");
3455 jlong sum = 0;
3456 for (int j = 0; j < length; j++) {
3457 int original_index = method_ordering->at(j);
3458 guarantee(original_index >= 0, "invalid method ordering index");
3459 guarantee(original_index < length, "invalid method ordering index");
3460 sum += original_index;
3461 }
3462 // Verify sum of indices 0,1,...,length-1
3463 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3464 } else {
3465 guarantee(length == 0, "invalid method ordering length");
3466 }
3467 }
3469 // Verify default methods
3470 if (default_methods() != NULL) {
3471 Array<Method*>* methods = this->default_methods();
3472 for (int j = 0; j < methods->length(); j++) {
3473 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3474 }
3475 for (int j = 0; j < methods->length() - 1; j++) {
3476 Method* m1 = methods->at(j);
3477 Method* m2 = methods->at(j + 1);
3478 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3479 }
3480 }
3482 // Verify JNI static field identifiers
3483 if (jni_ids() != NULL) {
3484 jni_ids()->verify(this);
3485 }
3487 // Verify other fields
3488 if (array_klasses() != NULL) {
3489 guarantee(array_klasses()->is_klass(), "should be klass");
3490 }
3491 if (constants() != NULL) {
3492 guarantee(constants()->is_constantPool(), "should be constant pool");
3493 }
3494 const Klass* host = host_klass();
3495 if (host != NULL) {
3496 guarantee(host->is_klass(), "should be klass");
3497 }
3498 }
3500 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3501 Klass::oop_verify_on(obj, st);
3502 VerifyFieldClosure blk;
3503 obj->oop_iterate_no_header(&blk);
3504 }
3507 // JNIid class for jfieldIDs only
3508 // Note to reviewers:
3509 // These JNI functions are just moved over to column 1 and not changed
3510 // in the compressed oops workspace.
3511 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3512 _holder = holder;
3513 _offset = offset;
3514 _next = next;
3515 debug_only(_is_static_field_id = false;)
3516 }
3519 JNIid* JNIid::find(int offset) {
3520 JNIid* current = this;
3521 while (current != NULL) {
3522 if (current->offset() == offset) return current;
3523 current = current->next();
3524 }
3525 return NULL;
3526 }
3528 void JNIid::deallocate(JNIid* current) {
3529 while (current != NULL) {
3530 JNIid* next = current->next();
3531 delete current;
3532 current = next;
3533 }
3534 }
3537 void JNIid::verify(Klass* holder) {
3538 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3539 int end_field_offset;
3540 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3542 JNIid* current = this;
3543 while (current != NULL) {
3544 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3545 #ifdef ASSERT
3546 int o = current->offset();
3547 if (current->is_static_field_id()) {
3548 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3549 }
3550 #endif
3551 current = current->next();
3552 }
3553 }
3556 #ifdef ASSERT
3557 void InstanceKlass::set_init_state(ClassState state) {
3558 bool good_state = is_shared() ? (_init_state <= state)
3559 : (_init_state < state);
3560 assert(good_state || state == allocated, "illegal state transition");
3561 _init_state = (u1)state;
3562 }
3563 #endif
3566 // RedefineClasses() support for previous versions:
3568 // Purge previous versions
3569 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3570 if (ik->previous_versions() != NULL) {
3571 // This klass has previous versions so see what we can cleanup
3572 // while it is safe to do so.
3574 int deleted_count = 0; // leave debugging breadcrumbs
3575 int live_count = 0;
3576 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3577 ClassLoaderData::the_null_class_loader_data() :
3578 ik->class_loader_data();
3580 // RC_TRACE macro has an embedded ResourceMark
3581 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3582 ik->external_name(), ik->previous_versions()->length()));
3584 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3585 // check the previous versions array
3586 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3587 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3588 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3590 ConstantPool* pvcp = cp_ref;
3591 if (!pvcp->on_stack()) {
3592 // If the constant pool isn't on stack, none of the methods
3593 // are executing. Delete all the methods, the constant pool and
3594 // and this previous version node.
3595 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3596 if (method_refs != NULL) {
3597 for (int j = method_refs->length() - 1; j >= 0; j--) {
3598 Method* method = method_refs->at(j);
3599 assert(method != NULL, "method ref was unexpectedly cleared");
3600 method_refs->remove_at(j);
3601 // method will be freed with associated class.
3602 }
3603 }
3604 // Remove the constant pool
3605 delete pv_node;
3606 // Since we are traversing the array backwards, we don't have to
3607 // do anything special with the index.
3608 ik->previous_versions()->remove_at(i);
3609 deleted_count++;
3610 continue;
3611 } else {
3612 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3613 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3614 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3615 live_count++;
3616 }
3618 // At least one method is live in this previous version, clean out
3619 // the others or mark them as obsolete.
3620 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3621 if (method_refs != NULL) {
3622 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3623 method_refs->length()));
3624 for (int j = method_refs->length() - 1; j >= 0; j--) {
3625 Method* method = method_refs->at(j);
3626 assert(method != NULL, "method ref was unexpectedly cleared");
3628 // Remove the emcp method if it's not executing
3629 // If it's been made obsolete by a redefinition of a non-emcp
3630 // method, mark it as obsolete but leave it to clean up later.
3631 if (!method->on_stack()) {
3632 method_refs->remove_at(j);
3633 } else if (emcp_method_count == 0) {
3634 method->set_is_obsolete();
3635 } else {
3636 // RC_TRACE macro has an embedded ResourceMark
3637 RC_TRACE(0x00000200,
3638 ("purge: %s(%s): prev method @%d in version @%d is alive",
3639 method->name()->as_C_string(),
3640 method->signature()->as_C_string(), j, i));
3641 }
3642 }
3643 }
3644 }
3645 assert(ik->previous_versions()->length() == live_count, "sanity check");
3646 RC_TRACE(0x00000200,
3647 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3648 deleted_count));
3649 }
3650 }
3652 // External interface for use during class unloading.
3653 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3654 // Call with >0 emcp methods since they are not currently being redefined.
3655 purge_previous_versions_internal(ik, 1);
3656 }
3659 // Potentially add an information node that contains pointers to the
3660 // interesting parts of the previous version of the_class.
3661 // This is also where we clean out any unused references.
3662 // Note that while we delete nodes from the _previous_versions
3663 // array, we never delete the array itself until the klass is
3664 // unloaded. The has_been_redefined() query depends on that fact.
3665 //
3666 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3667 BitMap* emcp_methods, int emcp_method_count) {
3668 assert(Thread::current()->is_VM_thread(),
3669 "only VMThread can add previous versions");
3671 if (_previous_versions == NULL) {
3672 // This is the first previous version so make some space.
3673 // Start with 2 elements under the assumption that the class
3674 // won't be redefined much.
3675 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3676 GrowableArray<PreviousVersionNode *>(2, true);
3677 }
3679 ConstantPool* cp_ref = ikh->constants();
3681 // RC_TRACE macro has an embedded ResourceMark
3682 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3683 "on_stack=%d",
3684 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3685 cp_ref->on_stack()));
3687 // If the constant pool for this previous version of the class
3688 // is not marked as being on the stack, then none of the methods
3689 // in this previous version of the class are on the stack so
3690 // we don't need to create a new PreviousVersionNode. However,
3691 // we still need to examine older previous versions below.
3692 Array<Method*>* old_methods = ikh->methods();
3694 if (cp_ref->on_stack()) {
3695 PreviousVersionNode * pv_node = NULL;
3696 if (emcp_method_count == 0) {
3697 // non-shared ConstantPool gets a reference
3698 pv_node = new PreviousVersionNode(cp_ref, NULL);
3699 RC_TRACE(0x00000400,
3700 ("add: all methods are obsolete; flushing any EMCP refs"));
3701 } else {
3702 int local_count = 0;
3703 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3704 GrowableArray<Method*>(emcp_method_count, true);
3705 for (int i = 0; i < old_methods->length(); i++) {
3706 if (emcp_methods->at(i)) {
3707 // this old method is EMCP. Save it only if it's on the stack
3708 Method* old_method = old_methods->at(i);
3709 if (old_method->on_stack()) {
3710 method_refs->append(old_method);
3711 }
3712 if (++local_count >= emcp_method_count) {
3713 // no more EMCP methods so bail out now
3714 break;
3715 }
3716 }
3717 }
3718 // non-shared ConstantPool gets a reference
3719 pv_node = new PreviousVersionNode(cp_ref, method_refs);
3720 }
3721 // append new previous version.
3722 _previous_versions->append(pv_node);
3723 }
3725 // Since the caller is the VMThread and we are at a safepoint, this
3726 // is a good time to clear out unused references.
3728 RC_TRACE(0x00000400, ("add: previous version length=%d",
3729 _previous_versions->length()));
3731 // Purge previous versions not executing on the stack
3732 purge_previous_versions_internal(this, emcp_method_count);
3734 int obsolete_method_count = old_methods->length() - emcp_method_count;
3736 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3737 _previous_versions->length() > 0) {
3738 // We have a mix of obsolete and EMCP methods so we have to
3739 // clear out any matching EMCP method entries the hard way.
3740 int local_count = 0;
3741 for (int i = 0; i < old_methods->length(); i++) {
3742 if (!emcp_methods->at(i)) {
3743 // only obsolete methods are interesting
3744 Method* old_method = old_methods->at(i);
3745 Symbol* m_name = old_method->name();
3746 Symbol* m_signature = old_method->signature();
3748 // we might not have added the last entry
3749 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3750 // check the previous versions array for non executing obsolete methods
3751 PreviousVersionNode * pv_node = _previous_versions->at(j);
3753 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3754 if (method_refs == NULL) {
3755 // We have run into a PreviousVersion generation where
3756 // all methods were made obsolete during that generation's
3757 // RedefineClasses() operation. At the time of that
3758 // operation, all EMCP methods were flushed so we don't
3759 // have to go back any further.
3760 //
3761 // A NULL method_refs is different than an empty method_refs.
3762 // We cannot infer any optimizations about older generations
3763 // from an empty method_refs for the current generation.
3764 break;
3765 }
3767 for (int k = method_refs->length() - 1; k >= 0; k--) {
3768 Method* method = method_refs->at(k);
3770 if (!method->is_obsolete() &&
3771 method->name() == m_name &&
3772 method->signature() == m_signature) {
3773 // The current RedefineClasses() call has made all EMCP
3774 // versions of this method obsolete so mark it as obsolete
3775 // and remove the reference.
3776 RC_TRACE(0x00000400,
3777 ("add: %s(%s): flush obsolete method @%d in version @%d",
3778 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3780 method->set_is_obsolete();
3781 // Leave obsolete methods on the previous version list to
3782 // clean up later.
3783 break;
3784 }
3785 }
3787 // The previous loop may not find a matching EMCP method, but
3788 // that doesn't mean that we can optimize and not go any
3789 // further back in the PreviousVersion generations. The EMCP
3790 // method for this generation could have already been deleted,
3791 // but there still may be an older EMCP method that has not
3792 // been deleted.
3793 }
3795 if (++local_count >= obsolete_method_count) {
3796 // no more obsolete methods so bail out now
3797 break;
3798 }
3799 }
3800 }
3801 }
3802 } // end add_previous_version()
3805 // Determine if InstanceKlass has a previous version.
3806 bool InstanceKlass::has_previous_version() const {
3807 return (_previous_versions != NULL && _previous_versions->length() > 0);
3808 } // end has_previous_version()
3811 InstanceKlass* InstanceKlass::get_klass_version(int version) {
3812 if (constants()->version() == version) {
3813 return this;
3814 }
3815 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
3816 for (PreviousVersionNode * pv_node = pvw.next_previous_version();
3817 pv_node != NULL; pv_node = pvw.next_previous_version()) {
3818 ConstantPool* prev_cp = pv_node->prev_constant_pool();
3819 if (prev_cp->version() == version) {
3820 return prev_cp->pool_holder();
3821 }
3822 }
3823 return NULL; // None found
3824 }
3827 Method* InstanceKlass::method_with_idnum(int idnum) {
3828 Method* m = NULL;
3829 if (idnum < methods()->length()) {
3830 m = methods()->at(idnum);
3831 }
3832 if (m == NULL || m->method_idnum() != idnum) {
3833 for (int index = 0; index < methods()->length(); ++index) {
3834 m = methods()->at(index);
3835 if (m->method_idnum() == idnum) {
3836 return m;
3837 }
3838 }
3839 // None found, return null for the caller to handle.
3840 return NULL;
3841 }
3842 return m;
3843 }
3846 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3847 if (idnum >= methods()->length()) {
3848 return NULL;
3849 }
3850 Method* m = methods()->at(idnum);
3851 if (m != NULL && m->orig_method_idnum() == idnum) {
3852 return m;
3853 }
3854 // Obsolete method idnum does not match the original idnum
3855 for (int index = 0; index < methods()->length(); ++index) {
3856 m = methods()->at(index);
3857 if (m->orig_method_idnum() == idnum) {
3858 return m;
3859 }
3860 }
3861 // None found, return null for the caller to handle.
3862 return NULL;
3863 }
3866 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3867 InstanceKlass* holder = get_klass_version(version);
3868 if (holder == NULL) {
3869 return NULL; // The version of klass is gone, no method is found
3870 }
3871 Method* method = holder->method_with_orig_idnum(idnum);
3872 return method;
3873 }
3876 jint InstanceKlass::get_cached_class_file_len() {
3877 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3878 }
3880 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3881 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3882 }
3885 // Construct a PreviousVersionNode entry for the array hung off
3886 // the InstanceKlass.
3887 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3888 GrowableArray<Method*>* prev_EMCP_methods) {
3890 _prev_constant_pool = prev_constant_pool;
3891 _prev_EMCP_methods = prev_EMCP_methods;
3892 }
3895 // Destroy a PreviousVersionNode
3896 PreviousVersionNode::~PreviousVersionNode() {
3897 if (_prev_constant_pool != NULL) {
3898 _prev_constant_pool = NULL;
3899 }
3901 if (_prev_EMCP_methods != NULL) {
3902 delete _prev_EMCP_methods;
3903 }
3904 }
3906 // Construct a helper for walking the previous versions array
3907 PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) {
3908 _thread = thread;
3909 _previous_versions = ik->previous_versions();
3910 _current_index = 0;
3911 _current_p = NULL;
3912 _current_constant_pool_handle = constantPoolHandle(thread, ik->constants());
3913 }
3916 // Return the interesting information for the next previous version
3917 // of the klass. Returns NULL if there are no more previous versions.
3918 PreviousVersionNode* PreviousVersionWalker::next_previous_version() {
3919 if (_previous_versions == NULL) {
3920 // no previous versions so nothing to return
3921 return NULL;
3922 }
3924 _current_p = NULL; // reset to NULL
3925 _current_constant_pool_handle = NULL;
3927 int length = _previous_versions->length();
3929 while (_current_index < length) {
3930 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3932 // Save a handle to the constant pool for this previous version,
3933 // which keeps all the methods from being deallocated.
3934 _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool());
3935 _current_p = pv_node;
3936 return pv_node;
3937 }
3939 return NULL;
3940 } // end next_previous_version()