Mon, 07 Jul 2014 10:12:40 +0200
8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com
1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/verifier.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "gc_implementation/shared/markSweep.inline.hpp"
32 #include "gc_interface/collectedHeap.inline.hpp"
33 #include "interpreter/oopMapCache.hpp"
34 #include "interpreter/rewriter.hpp"
35 #include "jvmtifiles/jvmti.h"
36 #include "memory/genOopClosures.inline.hpp"
37 #include "memory/heapInspection.hpp"
38 #include "memory/iterator.inline.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/oopFactory.hpp"
41 #include "oops/fieldStreams.hpp"
42 #include "oops/instanceClassLoaderKlass.hpp"
43 #include "oops/instanceKlass.hpp"
44 #include "oops/instanceMirrorKlass.hpp"
45 #include "oops/instanceOop.hpp"
46 #include "oops/klass.inline.hpp"
47 #include "oops/method.hpp"
48 #include "oops/oop.inline.hpp"
49 #include "oops/symbol.hpp"
50 #include "prims/jvmtiExport.hpp"
51 #include "prims/jvmtiRedefineClassesTrace.hpp"
52 #include "prims/jvmtiRedefineClasses.hpp"
53 #include "prims/methodComparator.hpp"
54 #include "runtime/fieldDescriptor.hpp"
55 #include "runtime/handles.inline.hpp"
56 #include "runtime/javaCalls.hpp"
57 #include "runtime/mutexLocker.hpp"
58 #include "runtime/orderAccess.inline.hpp"
59 #include "runtime/thread.inline.hpp"
60 #include "services/classLoadingService.hpp"
61 #include "services/threadService.hpp"
62 #include "utilities/dtrace.hpp"
63 #include "utilities/macros.hpp"
64 #if INCLUDE_ALL_GCS
65 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
66 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
67 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
68 #include "gc_implementation/g1/g1RemSet.inline.hpp"
69 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
70 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
71 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
72 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
73 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
74 #include "oops/oop.pcgc.inline.hpp"
75 #endif // INCLUDE_ALL_GCS
76 #ifdef COMPILER1
77 #include "c1/c1_Compiler.hpp"
78 #endif
80 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
82 #ifdef DTRACE_ENABLED
84 #ifndef USDT2
86 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
87 char*, intptr_t, oop, intptr_t);
88 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
89 char*, intptr_t, oop, intptr_t, int);
90 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
91 char*, intptr_t, oop, intptr_t, int);
92 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
93 char*, intptr_t, oop, intptr_t, int);
94 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
95 char*, intptr_t, oop, intptr_t, int);
96 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
97 char*, intptr_t, oop, intptr_t, int);
98 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
99 char*, intptr_t, oop, intptr_t, int);
100 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
101 char*, intptr_t, oop, intptr_t, int);
103 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
104 { \
105 char* data = NULL; \
106 int len = 0; \
107 Symbol* name = (clss)->name(); \
108 if (name != NULL) { \
109 data = (char*)name->bytes(); \
110 len = name->utf8_length(); \
111 } \
112 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \
113 data, len, SOLARIS_ONLY((void *))(clss)->class_loader(), thread_type); \
114 }
116 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
117 { \
118 char* data = NULL; \
119 int len = 0; \
120 Symbol* name = (clss)->name(); \
121 if (name != NULL) { \
122 data = (char*)name->bytes(); \
123 len = name->utf8_length(); \
124 } \
125 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \
126 data, len, SOLARIS_ONLY((void *))(clss)->class_loader(), thread_type, wait); \
127 }
128 #else /* USDT2 */
130 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
131 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
132 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
133 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
134 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
135 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
136 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
137 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
138 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
139 { \
140 char* data = NULL; \
141 int len = 0; \
142 Symbol* name = (clss)->name(); \
143 if (name != NULL) { \
144 data = (char*)name->bytes(); \
145 len = name->utf8_length(); \
146 } \
147 HOTSPOT_CLASS_INITIALIZATION_##type( \
148 data, len, (clss)->class_loader(), thread_type); \
149 }
151 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
152 { \
153 char* data = NULL; \
154 int len = 0; \
155 Symbol* name = (clss)->name(); \
156 if (name != NULL) { \
157 data = (char*)name->bytes(); \
158 len = name->utf8_length(); \
159 } \
160 HOTSPOT_CLASS_INITIALIZATION_##type( \
161 data, len, (clss)->class_loader(), thread_type, wait); \
162 }
163 #endif /* USDT2 */
165 #else // ndef DTRACE_ENABLED
167 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
168 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
170 #endif // ndef DTRACE_ENABLED
172 volatile int InstanceKlass::_total_instanceKlass_count = 0;
174 InstanceKlass* InstanceKlass::allocate_instance_klass(
175 ClassLoaderData* loader_data,
176 int vtable_len,
177 int itable_len,
178 int static_field_size,
179 int nonstatic_oop_map_size,
180 ReferenceType rt,
181 AccessFlags access_flags,
182 Symbol* name,
183 Klass* super_klass,
184 bool is_anonymous,
185 TRAPS) {
187 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
188 access_flags.is_interface(), is_anonymous);
190 // Allocation
191 InstanceKlass* ik;
192 if (rt == REF_NONE) {
193 if (name == vmSymbols::java_lang_Class()) {
194 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
195 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
196 access_flags, is_anonymous);
197 } else if (name == vmSymbols::java_lang_ClassLoader() ||
198 (SystemDictionary::ClassLoader_klass_loaded() &&
199 super_klass != NULL &&
200 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
201 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
202 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
203 access_flags, is_anonymous);
204 } else {
205 // normal class
206 ik = new (loader_data, size, THREAD) InstanceKlass(
207 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
208 access_flags, is_anonymous);
209 }
210 } else {
211 // reference klass
212 ik = new (loader_data, size, THREAD) InstanceRefKlass(
213 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
214 access_flags, is_anonymous);
215 }
217 // Check for pending exception before adding to the loader data and incrementing
218 // class count. Can get OOM here.
219 if (HAS_PENDING_EXCEPTION) {
220 return NULL;
221 }
223 // Add all classes to our internal class loader list here,
224 // including classes in the bootstrap (NULL) class loader.
225 loader_data->add_class(ik);
227 Atomic::inc(&_total_instanceKlass_count);
228 return ik;
229 }
232 // copy method ordering from resource area to Metaspace
233 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
234 if (m != NULL) {
235 // allocate a new array and copy contents (memcpy?)
236 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
237 for (int i = 0; i < m->length(); i++) {
238 _method_ordering->at_put(i, m->at(i));
239 }
240 } else {
241 _method_ordering = Universe::the_empty_int_array();
242 }
243 }
245 // create a new array of vtable_indices for default methods
246 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
247 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
248 assert(default_vtable_indices() == NULL, "only create once");
249 set_default_vtable_indices(vtable_indices);
250 return vtable_indices;
251 }
253 InstanceKlass::InstanceKlass(int vtable_len,
254 int itable_len,
255 int static_field_size,
256 int nonstatic_oop_map_size,
257 ReferenceType rt,
258 AccessFlags access_flags,
259 bool is_anonymous) {
260 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
262 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
263 access_flags.is_interface(), is_anonymous);
265 set_vtable_length(vtable_len);
266 set_itable_length(itable_len);
267 set_static_field_size(static_field_size);
268 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
269 set_access_flags(access_flags);
270 _misc_flags = 0; // initialize to zero
271 set_is_anonymous(is_anonymous);
272 assert(size() == iksize, "wrong size for object");
274 set_array_klasses(NULL);
275 set_methods(NULL);
276 set_method_ordering(NULL);
277 set_default_methods(NULL);
278 set_default_vtable_indices(NULL);
279 set_local_interfaces(NULL);
280 set_transitive_interfaces(NULL);
281 init_implementor();
282 set_fields(NULL, 0);
283 set_constants(NULL);
284 set_class_loader_data(NULL);
285 set_source_file_name_index(0);
286 set_source_debug_extension(NULL, 0);
287 set_array_name(NULL);
288 set_inner_classes(NULL);
289 set_static_oop_field_count(0);
290 set_nonstatic_field_size(0);
291 set_is_marked_dependent(false);
292 set_has_unloaded_dependent(false);
293 set_init_state(InstanceKlass::allocated);
294 set_init_thread(NULL);
295 set_reference_type(rt);
296 set_oop_map_cache(NULL);
297 set_jni_ids(NULL);
298 set_osr_nmethods_head(NULL);
299 set_breakpoints(NULL);
300 init_previous_versions();
301 set_generic_signature_index(0);
302 release_set_methods_jmethod_ids(NULL);
303 set_annotations(NULL);
304 set_jvmti_cached_class_field_map(NULL);
305 set_initial_method_idnum(0);
306 _dependencies = NULL;
307 set_jvmti_cached_class_field_map(NULL);
308 set_cached_class_file(NULL);
309 set_initial_method_idnum(0);
310 set_minor_version(0);
311 set_major_version(0);
312 NOT_PRODUCT(_verify_count = 0;)
314 // initialize the non-header words to zero
315 intptr_t* p = (intptr_t*)this;
316 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
317 p[index] = NULL_WORD;
318 }
320 // Set temporary value until parseClassFile updates it with the real instance
321 // size.
322 set_layout_helper(Klass::instance_layout_helper(0, true));
323 }
326 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
327 Array<Method*>* methods) {
328 if (methods != NULL && methods != Universe::the_empty_method_array() &&
329 !methods->is_shared()) {
330 for (int i = 0; i < methods->length(); i++) {
331 Method* method = methods->at(i);
332 if (method == NULL) continue; // maybe null if error processing
333 // Only want to delete methods that are not executing for RedefineClasses.
334 // The previous version will point to them so they're not totally dangling
335 assert (!method->on_stack(), "shouldn't be called with methods on stack");
336 MetadataFactory::free_metadata(loader_data, method);
337 }
338 MetadataFactory::free_array<Method*>(loader_data, methods);
339 }
340 }
342 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
343 Klass* super_klass,
344 Array<Klass*>* local_interfaces,
345 Array<Klass*>* transitive_interfaces) {
346 // Only deallocate transitive interfaces if not empty, same as super class
347 // or same as local interfaces. See code in parseClassFile.
348 Array<Klass*>* ti = transitive_interfaces;
349 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
350 // check that the interfaces don't come from super class
351 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
352 InstanceKlass::cast(super_klass)->transitive_interfaces();
353 if (ti != sti && ti != NULL && !ti->is_shared()) {
354 MetadataFactory::free_array<Klass*>(loader_data, ti);
355 }
356 }
358 // local interfaces can be empty
359 if (local_interfaces != Universe::the_empty_klass_array() &&
360 local_interfaces != NULL && !local_interfaces->is_shared()) {
361 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
362 }
363 }
365 // This function deallocates the metadata and C heap pointers that the
366 // InstanceKlass points to.
367 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
369 // Orphan the mirror first, CMS thinks it's still live.
370 if (java_mirror() != NULL) {
371 java_lang_Class::set_klass(java_mirror(), NULL);
372 }
374 // Need to take this class off the class loader data list.
375 loader_data->remove_class(this);
377 // The array_klass for this class is created later, after error handling.
378 // For class redefinition, we keep the original class so this scratch class
379 // doesn't have an array class. Either way, assert that there is nothing
380 // to deallocate.
381 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
383 // Release C heap allocated data that this might point to, which includes
384 // reference counting symbol names.
385 release_C_heap_structures();
387 deallocate_methods(loader_data, methods());
388 set_methods(NULL);
390 if (method_ordering() != NULL &&
391 method_ordering() != Universe::the_empty_int_array() &&
392 !method_ordering()->is_shared()) {
393 MetadataFactory::free_array<int>(loader_data, method_ordering());
394 }
395 set_method_ordering(NULL);
397 // default methods can be empty
398 if (default_methods() != NULL &&
399 default_methods() != Universe::the_empty_method_array() &&
400 !default_methods()->is_shared()) {
401 MetadataFactory::free_array<Method*>(loader_data, default_methods());
402 }
403 // Do NOT deallocate the default methods, they are owned by superinterfaces.
404 set_default_methods(NULL);
406 // default methods vtable indices can be empty
407 if (default_vtable_indices() != NULL &&
408 !default_vtable_indices()->is_shared()) {
409 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
410 }
411 set_default_vtable_indices(NULL);
414 // This array is in Klass, but remove it with the InstanceKlass since
415 // this place would be the only caller and it can share memory with transitive
416 // interfaces.
417 if (secondary_supers() != NULL &&
418 secondary_supers() != Universe::the_empty_klass_array() &&
419 secondary_supers() != transitive_interfaces() &&
420 !secondary_supers()->is_shared()) {
421 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
422 }
423 set_secondary_supers(NULL);
425 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
426 set_transitive_interfaces(NULL);
427 set_local_interfaces(NULL);
429 if (fields() != NULL && !fields()->is_shared()) {
430 MetadataFactory::free_array<jushort>(loader_data, fields());
431 }
432 set_fields(NULL, 0);
434 // If a method from a redefined class is using this constant pool, don't
435 // delete it, yet. The new class's previous version will point to this.
436 if (constants() != NULL) {
437 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
438 if (!constants()->is_shared()) {
439 MetadataFactory::free_metadata(loader_data, constants());
440 }
441 set_constants(NULL);
442 }
444 if (inner_classes() != NULL &&
445 inner_classes() != Universe::the_empty_short_array() &&
446 !inner_classes()->is_shared()) {
447 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
448 }
449 set_inner_classes(NULL);
451 // We should deallocate the Annotations instance if it's not in shared spaces.
452 if (annotations() != NULL && !annotations()->is_shared()) {
453 MetadataFactory::free_metadata(loader_data, annotations());
454 }
455 set_annotations(NULL);
456 }
458 bool InstanceKlass::should_be_initialized() const {
459 return !is_initialized();
460 }
462 klassVtable* InstanceKlass::vtable() const {
463 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
464 }
466 klassItable* InstanceKlass::itable() const {
467 return new klassItable(instanceKlassHandle(this));
468 }
470 void InstanceKlass::eager_initialize(Thread *thread) {
471 if (!EagerInitialization) return;
473 if (this->is_not_initialized()) {
474 // abort if the the class has a class initializer
475 if (this->class_initializer() != NULL) return;
477 // abort if it is java.lang.Object (initialization is handled in genesis)
478 Klass* super = this->super();
479 if (super == NULL) return;
481 // abort if the super class should be initialized
482 if (!InstanceKlass::cast(super)->is_initialized()) return;
484 // call body to expose the this pointer
485 instanceKlassHandle this_oop(thread, this);
486 eager_initialize_impl(this_oop);
487 }
488 }
490 // JVMTI spec thinks there are signers and protection domain in the
491 // instanceKlass. These accessors pretend these fields are there.
492 // The hprof specification also thinks these fields are in InstanceKlass.
493 oop InstanceKlass::protection_domain() const {
494 // return the protection_domain from the mirror
495 return java_lang_Class::protection_domain(java_mirror());
496 }
498 // To remove these from requires an incompatible change and CCC request.
499 objArrayOop InstanceKlass::signers() const {
500 // return the signers from the mirror
501 return java_lang_Class::signers(java_mirror());
502 }
504 oop InstanceKlass::init_lock() const {
505 // return the init lock from the mirror
506 oop lock = java_lang_Class::init_lock(java_mirror());
507 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
508 "only fully initialized state can have a null lock");
509 return lock;
510 }
512 // Set the initialization lock to null so the object can be GC'ed. Any racing
513 // threads to get this lock will see a null lock and will not lock.
514 // That's okay because they all check for initialized state after getting
515 // the lock and return.
516 void InstanceKlass::fence_and_clear_init_lock() {
517 // make sure previous stores are all done, notably the init_state.
518 OrderAccess::storestore();
519 java_lang_Class::set_init_lock(java_mirror(), NULL);
520 assert(!is_not_initialized(), "class must be initialized now");
521 }
523 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
524 EXCEPTION_MARK;
525 oop init_lock = this_oop->init_lock();
526 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
528 // abort if someone beat us to the initialization
529 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
531 ClassState old_state = this_oop->init_state();
532 link_class_impl(this_oop, true, THREAD);
533 if (HAS_PENDING_EXCEPTION) {
534 CLEAR_PENDING_EXCEPTION;
535 // Abort if linking the class throws an exception.
537 // Use a test to avoid redundantly resetting the state if there's
538 // no change. Set_init_state() asserts that state changes make
539 // progress, whereas here we might just be spinning in place.
540 if( old_state != this_oop->_init_state )
541 this_oop->set_init_state (old_state);
542 } else {
543 // linking successfull, mark class as initialized
544 this_oop->set_init_state (fully_initialized);
545 this_oop->fence_and_clear_init_lock();
546 // trace
547 if (TraceClassInitialization) {
548 ResourceMark rm(THREAD);
549 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
550 }
551 }
552 }
555 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
556 // process. The step comments refers to the procedure described in that section.
557 // Note: implementation moved to static method to expose the this pointer.
558 void InstanceKlass::initialize(TRAPS) {
559 if (this->should_be_initialized()) {
560 HandleMark hm(THREAD);
561 instanceKlassHandle this_oop(THREAD, this);
562 initialize_impl(this_oop, CHECK);
563 // Note: at this point the class may be initialized
564 // OR it may be in the state of being initialized
565 // in case of recursive initialization!
566 } else {
567 assert(is_initialized(), "sanity check");
568 }
569 }
572 bool InstanceKlass::verify_code(
573 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
574 // 1) Verify the bytecodes
575 Verifier::Mode mode =
576 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
577 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
578 }
581 // Used exclusively by the shared spaces dump mechanism to prevent
582 // classes mapped into the shared regions in new VMs from appearing linked.
584 void InstanceKlass::unlink_class() {
585 assert(is_linked(), "must be linked");
586 _init_state = loaded;
587 }
589 void InstanceKlass::link_class(TRAPS) {
590 assert(is_loaded(), "must be loaded");
591 if (!is_linked()) {
592 HandleMark hm(THREAD);
593 instanceKlassHandle this_oop(THREAD, this);
594 link_class_impl(this_oop, true, CHECK);
595 }
596 }
598 // Called to verify that a class can link during initialization, without
599 // throwing a VerifyError.
600 bool InstanceKlass::link_class_or_fail(TRAPS) {
601 assert(is_loaded(), "must be loaded");
602 if (!is_linked()) {
603 HandleMark hm(THREAD);
604 instanceKlassHandle this_oop(THREAD, this);
605 link_class_impl(this_oop, false, CHECK_false);
606 }
607 return is_linked();
608 }
610 bool InstanceKlass::link_class_impl(
611 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
612 // check for error state
613 if (this_oop->is_in_error_state()) {
614 ResourceMark rm(THREAD);
615 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
616 this_oop->external_name(), false);
617 }
618 // return if already verified
619 if (this_oop->is_linked()) {
620 return true;
621 }
623 // Timing
624 // timer handles recursion
625 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
626 JavaThread* jt = (JavaThread*)THREAD;
628 // link super class before linking this class
629 instanceKlassHandle super(THREAD, this_oop->super());
630 if (super.not_null()) {
631 if (super->is_interface()) { // check if super class is an interface
632 ResourceMark rm(THREAD);
633 Exceptions::fthrow(
634 THREAD_AND_LOCATION,
635 vmSymbols::java_lang_IncompatibleClassChangeError(),
636 "class %s has interface %s as super class",
637 this_oop->external_name(),
638 super->external_name()
639 );
640 return false;
641 }
643 link_class_impl(super, throw_verifyerror, CHECK_false);
644 }
646 // link all interfaces implemented by this class before linking this class
647 Array<Klass*>* interfaces = this_oop->local_interfaces();
648 int num_interfaces = interfaces->length();
649 for (int index = 0; index < num_interfaces; index++) {
650 HandleMark hm(THREAD);
651 instanceKlassHandle ih(THREAD, interfaces->at(index));
652 link_class_impl(ih, throw_verifyerror, CHECK_false);
653 }
655 // in case the class is linked in the process of linking its superclasses
656 if (this_oop->is_linked()) {
657 return true;
658 }
660 // trace only the link time for this klass that includes
661 // the verification time
662 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
663 ClassLoader::perf_class_link_selftime(),
664 ClassLoader::perf_classes_linked(),
665 jt->get_thread_stat()->perf_recursion_counts_addr(),
666 jt->get_thread_stat()->perf_timers_addr(),
667 PerfClassTraceTime::CLASS_LINK);
669 // verification & rewriting
670 {
671 oop init_lock = this_oop->init_lock();
672 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
673 // rewritten will have been set if loader constraint error found
674 // on an earlier link attempt
675 // don't verify or rewrite if already rewritten
677 if (!this_oop->is_linked()) {
678 if (!this_oop->is_rewritten()) {
679 {
680 // Timer includes any side effects of class verification (resolution,
681 // etc), but not recursive entry into verify_code().
682 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
683 ClassLoader::perf_class_verify_selftime(),
684 ClassLoader::perf_classes_verified(),
685 jt->get_thread_stat()->perf_recursion_counts_addr(),
686 jt->get_thread_stat()->perf_timers_addr(),
687 PerfClassTraceTime::CLASS_VERIFY);
688 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
689 if (!verify_ok) {
690 return false;
691 }
692 }
694 // Just in case a side-effect of verify linked this class already
695 // (which can sometimes happen since the verifier loads classes
696 // using custom class loaders, which are free to initialize things)
697 if (this_oop->is_linked()) {
698 return true;
699 }
701 // also sets rewritten
702 this_oop->rewrite_class(CHECK_false);
703 }
705 // relocate jsrs and link methods after they are all rewritten
706 this_oop->link_methods(CHECK_false);
708 // Initialize the vtable and interface table after
709 // methods have been rewritten since rewrite may
710 // fabricate new Method*s.
711 // also does loader constraint checking
712 if (!this_oop()->is_shared()) {
713 ResourceMark rm(THREAD);
714 this_oop->vtable()->initialize_vtable(true, CHECK_false);
715 this_oop->itable()->initialize_itable(true, CHECK_false);
716 }
717 #ifdef ASSERT
718 else {
719 ResourceMark rm(THREAD);
720 this_oop->vtable()->verify(tty, true);
721 // In case itable verification is ever added.
722 // this_oop->itable()->verify(tty, true);
723 }
724 #endif
725 this_oop->set_init_state(linked);
726 if (JvmtiExport::should_post_class_prepare()) {
727 Thread *thread = THREAD;
728 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
729 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
730 }
731 }
732 }
733 return true;
734 }
737 // Rewrite the byte codes of all of the methods of a class.
738 // The rewriter must be called exactly once. Rewriting must happen after
739 // verification but before the first method of the class is executed.
740 void InstanceKlass::rewrite_class(TRAPS) {
741 assert(is_loaded(), "must be loaded");
742 instanceKlassHandle this_oop(THREAD, this);
743 if (this_oop->is_rewritten()) {
744 assert(this_oop()->is_shared(), "rewriting an unshared class?");
745 return;
746 }
747 Rewriter::rewrite(this_oop, CHECK);
748 this_oop->set_rewritten();
749 }
751 // Now relocate and link method entry points after class is rewritten.
752 // This is outside is_rewritten flag. In case of an exception, it can be
753 // executed more than once.
754 void InstanceKlass::link_methods(TRAPS) {
755 int len = methods()->length();
756 for (int i = len-1; i >= 0; i--) {
757 methodHandle m(THREAD, methods()->at(i));
759 // Set up method entry points for compiler and interpreter .
760 m->link_method(m, CHECK);
762 // This is for JVMTI and unrelated to relocator but the last thing we do
763 #ifdef ASSERT
764 if (StressMethodComparator) {
765 ResourceMark rm(THREAD);
766 static int nmc = 0;
767 for (int j = i; j >= 0 && j >= i-4; j--) {
768 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
769 bool z = MethodComparator::methods_EMCP(m(),
770 methods()->at(j));
771 if (j == i && !z) {
772 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
773 assert(z, "method must compare equal to itself");
774 }
775 }
776 }
777 #endif //ASSERT
778 }
779 }
782 void InstanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
783 // Make sure klass is linked (verified) before initialization
784 // A class could already be verified, since it has been reflected upon.
785 this_oop->link_class(CHECK);
787 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_oop()), -1);
789 bool wait = false;
791 // refer to the JVM book page 47 for description of steps
792 // Step 1
793 {
794 oop init_lock = this_oop->init_lock();
795 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
797 Thread *self = THREAD; // it's passed the current thread
799 // Step 2
800 // If we were to use wait() instead of waitInterruptibly() then
801 // we might end up throwing IE from link/symbol resolution sites
802 // that aren't expected to throw. This would wreak havoc. See 6320309.
803 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
804 wait = true;
805 ol.waitUninterruptibly(CHECK);
806 }
808 // Step 3
809 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
810 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_oop()), -1,wait);
811 return;
812 }
814 // Step 4
815 if (this_oop->is_initialized()) {
816 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_oop()), -1,wait);
817 return;
818 }
820 // Step 5
821 if (this_oop->is_in_error_state()) {
822 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_oop()), -1,wait);
823 ResourceMark rm(THREAD);
824 const char* desc = "Could not initialize class ";
825 const char* className = this_oop->external_name();
826 size_t msglen = strlen(desc) + strlen(className) + 1;
827 char* message = NEW_RESOURCE_ARRAY(char, msglen);
828 if (NULL == message) {
829 // Out of memory: can't create detailed error message
830 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
831 } else {
832 jio_snprintf(message, msglen, "%s%s", desc, className);
833 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
834 }
835 }
837 // Step 6
838 this_oop->set_init_state(being_initialized);
839 this_oop->set_init_thread(self);
840 }
842 // Step 7
843 Klass* super_klass = this_oop->super();
844 if (super_klass != NULL && !this_oop->is_interface() && super_klass->should_be_initialized()) {
845 super_klass->initialize(THREAD);
847 if (HAS_PENDING_EXCEPTION) {
848 Handle e(THREAD, PENDING_EXCEPTION);
849 CLEAR_PENDING_EXCEPTION;
850 {
851 EXCEPTION_MARK;
852 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
853 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
854 }
855 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_oop()), -1,wait);
856 THROW_OOP(e());
857 }
858 }
860 if (this_oop->has_default_methods()) {
861 // Step 7.5: initialize any interfaces which have default methods
862 for (int i = 0; i < this_oop->local_interfaces()->length(); ++i) {
863 Klass* iface = this_oop->local_interfaces()->at(i);
864 InstanceKlass* ik = InstanceKlass::cast(iface);
865 if (ik->has_default_methods() && ik->should_be_initialized()) {
866 ik->initialize(THREAD);
868 if (HAS_PENDING_EXCEPTION) {
869 Handle e(THREAD, PENDING_EXCEPTION);
870 CLEAR_PENDING_EXCEPTION;
871 {
872 EXCEPTION_MARK;
873 // Locks object, set state, and notify all waiting threads
874 this_oop->set_initialization_state_and_notify(
875 initialization_error, THREAD);
877 // ignore any exception thrown, superclass initialization error is
878 // thrown below
879 CLEAR_PENDING_EXCEPTION;
880 }
881 DTRACE_CLASSINIT_PROBE_WAIT(
882 super__failed, InstanceKlass::cast(this_oop()), -1, wait);
883 THROW_OOP(e());
884 }
885 }
886 }
887 }
889 // Step 8
890 {
891 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
892 JavaThread* jt = (JavaThread*)THREAD;
893 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_oop()), -1,wait);
894 // Timer includes any side effects of class initialization (resolution,
895 // etc), but not recursive entry into call_class_initializer().
896 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
897 ClassLoader::perf_class_init_selftime(),
898 ClassLoader::perf_classes_inited(),
899 jt->get_thread_stat()->perf_recursion_counts_addr(),
900 jt->get_thread_stat()->perf_timers_addr(),
901 PerfClassTraceTime::CLASS_CLINIT);
902 this_oop->call_class_initializer(THREAD);
903 }
905 // Step 9
906 if (!HAS_PENDING_EXCEPTION) {
907 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
908 { ResourceMark rm(THREAD);
909 debug_only(this_oop->vtable()->verify(tty, true);)
910 }
911 }
912 else {
913 // Step 10 and 11
914 Handle e(THREAD, PENDING_EXCEPTION);
915 CLEAR_PENDING_EXCEPTION;
916 {
917 EXCEPTION_MARK;
918 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
919 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
920 }
921 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_oop()), -1,wait);
922 if (e->is_a(SystemDictionary::Error_klass())) {
923 THROW_OOP(e());
924 } else {
925 JavaCallArguments args(e);
926 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
927 vmSymbols::throwable_void_signature(),
928 &args);
929 }
930 }
931 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_oop()), -1,wait);
932 }
935 // Note: implementation moved to static method to expose the this pointer.
936 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
937 instanceKlassHandle kh(THREAD, this);
938 set_initialization_state_and_notify_impl(kh, state, CHECK);
939 }
941 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
942 oop init_lock = this_oop->init_lock();
943 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
944 this_oop->set_init_state(state);
945 this_oop->fence_and_clear_init_lock();
946 ol.notify_all(CHECK);
947 }
949 // The embedded _implementor field can only record one implementor.
950 // When there are more than one implementors, the _implementor field
951 // is set to the interface Klass* itself. Following are the possible
952 // values for the _implementor field:
953 // NULL - no implementor
954 // implementor Klass* - one implementor
955 // self - more than one implementor
956 //
957 // The _implementor field only exists for interfaces.
958 void InstanceKlass::add_implementor(Klass* k) {
959 assert(Compile_lock->owned_by_self(), "");
960 assert(is_interface(), "not interface");
961 // Filter out my subinterfaces.
962 // (Note: Interfaces are never on the subklass list.)
963 if (InstanceKlass::cast(k)->is_interface()) return;
965 // Filter out subclasses whose supers already implement me.
966 // (Note: CHA must walk subclasses of direct implementors
967 // in order to locate indirect implementors.)
968 Klass* sk = InstanceKlass::cast(k)->super();
969 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
970 // We only need to check one immediate superclass, since the
971 // implements_interface query looks at transitive_interfaces.
972 // Any supers of the super have the same (or fewer) transitive_interfaces.
973 return;
975 Klass* ik = implementor();
976 if (ik == NULL) {
977 set_implementor(k);
978 } else if (ik != this) {
979 // There is already an implementor. Use itself as an indicator of
980 // more than one implementors.
981 set_implementor(this);
982 }
984 // The implementor also implements the transitive_interfaces
985 for (int index = 0; index < local_interfaces()->length(); index++) {
986 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
987 }
988 }
990 void InstanceKlass::init_implementor() {
991 if (is_interface()) {
992 set_implementor(NULL);
993 }
994 }
997 void InstanceKlass::process_interfaces(Thread *thread) {
998 // link this class into the implementors list of every interface it implements
999 Klass* this_as_klass_oop = this;
1000 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1001 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1002 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1003 assert(interf->is_interface(), "expected interface");
1004 interf->add_implementor(this_as_klass_oop);
1005 }
1006 }
1008 bool InstanceKlass::can_be_primary_super_slow() const {
1009 if (is_interface())
1010 return false;
1011 else
1012 return Klass::can_be_primary_super_slow();
1013 }
1015 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1016 // The secondaries are the implemented interfaces.
1017 InstanceKlass* ik = InstanceKlass::cast(this);
1018 Array<Klass*>* interfaces = ik->transitive_interfaces();
1019 int num_secondaries = num_extra_slots + interfaces->length();
1020 if (num_secondaries == 0) {
1021 // Must share this for correct bootstrapping!
1022 set_secondary_supers(Universe::the_empty_klass_array());
1023 return NULL;
1024 } else if (num_extra_slots == 0) {
1025 // The secondary super list is exactly the same as the transitive interfaces.
1026 // Redefine classes has to be careful not to delete this!
1027 set_secondary_supers(interfaces);
1028 return NULL;
1029 } else {
1030 // Copy transitive interfaces to a temporary growable array to be constructed
1031 // into the secondary super list with extra slots.
1032 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1033 for (int i = 0; i < interfaces->length(); i++) {
1034 secondaries->push(interfaces->at(i));
1035 }
1036 return secondaries;
1037 }
1038 }
1040 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1041 if (k->is_interface()) {
1042 return implements_interface(k);
1043 } else {
1044 return Klass::compute_is_subtype_of(k);
1045 }
1046 }
1048 bool InstanceKlass::implements_interface(Klass* k) const {
1049 if (this == k) return true;
1050 assert(k->is_interface(), "should be an interface class");
1051 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1052 if (transitive_interfaces()->at(i) == k) {
1053 return true;
1054 }
1055 }
1056 return false;
1057 }
1059 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1060 // Verify direct super interface
1061 if (this == k) return true;
1062 assert(k->is_interface(), "should be an interface class");
1063 for (int i = 0; i < local_interfaces()->length(); i++) {
1064 if (local_interfaces()->at(i) == k) {
1065 return true;
1066 }
1067 }
1068 return false;
1069 }
1071 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1072 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1073 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1074 report_java_out_of_memory("Requested array size exceeds VM limit");
1075 JvmtiExport::post_array_size_exhausted();
1076 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1077 }
1078 int size = objArrayOopDesc::object_size(length);
1079 Klass* ak = array_klass(n, CHECK_NULL);
1080 KlassHandle h_ak (THREAD, ak);
1081 objArrayOop o =
1082 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1083 return o;
1084 }
1086 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1087 if (TraceFinalizerRegistration) {
1088 tty->print("Registered ");
1089 i->print_value_on(tty);
1090 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
1091 }
1092 instanceHandle h_i(THREAD, i);
1093 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1094 JavaValue result(T_VOID);
1095 JavaCallArguments args(h_i);
1096 methodHandle mh (THREAD, Universe::finalizer_register_method());
1097 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1098 return h_i();
1099 }
1101 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1102 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1103 int size = size_helper(); // Query before forming handle.
1105 KlassHandle h_k(THREAD, this);
1107 instanceOop i;
1109 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1110 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1111 i = register_finalizer(i, CHECK_NULL);
1112 }
1113 return i;
1114 }
1116 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1117 if (is_interface() || is_abstract()) {
1118 ResourceMark rm(THREAD);
1119 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1120 : vmSymbols::java_lang_InstantiationException(), external_name());
1121 }
1122 if (this == SystemDictionary::Class_klass()) {
1123 ResourceMark rm(THREAD);
1124 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1125 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1126 }
1127 }
1129 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1130 instanceKlassHandle this_oop(THREAD, this);
1131 return array_klass_impl(this_oop, or_null, n, THREAD);
1132 }
1134 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
1135 if (this_oop->array_klasses() == NULL) {
1136 if (or_null) return NULL;
1138 ResourceMark rm;
1139 JavaThread *jt = (JavaThread *)THREAD;
1140 {
1141 // Atomic creation of array_klasses
1142 MutexLocker mc(Compile_lock, THREAD); // for vtables
1143 MutexLocker ma(MultiArray_lock, THREAD);
1145 // Check if update has already taken place
1146 if (this_oop->array_klasses() == NULL) {
1147 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_oop->class_loader_data(), 1, this_oop, CHECK_NULL);
1148 this_oop->set_array_klasses(k);
1149 }
1150 }
1151 }
1152 // _this will always be set at this point
1153 ObjArrayKlass* oak = (ObjArrayKlass*)this_oop->array_klasses();
1154 if (or_null) {
1155 return oak->array_klass_or_null(n);
1156 }
1157 return oak->array_klass(n, CHECK_NULL);
1158 }
1160 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1161 return array_klass_impl(or_null, 1, THREAD);
1162 }
1164 void InstanceKlass::call_class_initializer(TRAPS) {
1165 instanceKlassHandle ik (THREAD, this);
1166 call_class_initializer_impl(ik, THREAD);
1167 }
1169 static int call_class_initializer_impl_counter = 0; // for debugging
1171 Method* InstanceKlass::class_initializer() {
1172 Method* clinit = find_method(
1173 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1174 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1175 return clinit;
1176 }
1177 return NULL;
1178 }
1180 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
1181 if (ReplayCompiles &&
1182 (ReplaySuppressInitializers == 1 ||
1183 ReplaySuppressInitializers >= 2 && this_oop->class_loader() != NULL)) {
1184 // Hide the existence of the initializer for the purpose of replaying the compile
1185 return;
1186 }
1188 methodHandle h_method(THREAD, this_oop->class_initializer());
1189 assert(!this_oop->is_initialized(), "we cannot initialize twice");
1190 if (TraceClassInitialization) {
1191 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1192 this_oop->name()->print_value();
1193 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
1194 }
1195 if (h_method() != NULL) {
1196 JavaCallArguments args; // No arguments
1197 JavaValue result(T_VOID);
1198 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1199 }
1200 }
1203 void InstanceKlass::mask_for(methodHandle method, int bci,
1204 InterpreterOopMap* entry_for) {
1205 // Dirty read, then double-check under a lock.
1206 if (_oop_map_cache == NULL) {
1207 // Otherwise, allocate a new one.
1208 MutexLocker x(OopMapCacheAlloc_lock);
1209 // First time use. Allocate a cache in C heap
1210 if (_oop_map_cache == NULL) {
1211 // Release stores from OopMapCache constructor before assignment
1212 // to _oop_map_cache. C++ compilers on ppc do not emit the
1213 // required memory barrier only because of the volatile
1214 // qualifier of _oop_map_cache.
1215 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1216 }
1217 }
1218 // _oop_map_cache is constant after init; lookup below does is own locking.
1219 _oop_map_cache->lookup(method, bci, entry_for);
1220 }
1223 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1224 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1225 Symbol* f_name = fs.name();
1226 Symbol* f_sig = fs.signature();
1227 if (f_name == name && f_sig == sig) {
1228 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1229 return true;
1230 }
1231 }
1232 return false;
1233 }
1236 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1237 const int n = local_interfaces()->length();
1238 for (int i = 0; i < n; i++) {
1239 Klass* intf1 = local_interfaces()->at(i);
1240 assert(intf1->is_interface(), "just checking type");
1241 // search for field in current interface
1242 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1243 assert(fd->is_static(), "interface field must be static");
1244 return intf1;
1245 }
1246 // search for field in direct superinterfaces
1247 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1248 if (intf2 != NULL) return intf2;
1249 }
1250 // otherwise field lookup fails
1251 return NULL;
1252 }
1255 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1256 // search order according to newest JVM spec (5.4.3.2, p.167).
1257 // 1) search for field in current klass
1258 if (find_local_field(name, sig, fd)) {
1259 return const_cast<InstanceKlass*>(this);
1260 }
1261 // 2) search for field recursively in direct superinterfaces
1262 { Klass* intf = find_interface_field(name, sig, fd);
1263 if (intf != NULL) return intf;
1264 }
1265 // 3) apply field lookup recursively if superclass exists
1266 { Klass* supr = super();
1267 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1268 }
1269 // 4) otherwise field lookup fails
1270 return NULL;
1271 }
1274 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1275 // search order according to newest JVM spec (5.4.3.2, p.167).
1276 // 1) search for field in current klass
1277 if (find_local_field(name, sig, fd)) {
1278 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1279 }
1280 // 2) search for field recursively in direct superinterfaces
1281 if (is_static) {
1282 Klass* intf = find_interface_field(name, sig, fd);
1283 if (intf != NULL) return intf;
1284 }
1285 // 3) apply field lookup recursively if superclass exists
1286 { Klass* supr = super();
1287 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1288 }
1289 // 4) otherwise field lookup fails
1290 return NULL;
1291 }
1294 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1295 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1296 if (fs.offset() == offset) {
1297 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1298 if (fd->is_static() == is_static) return true;
1299 }
1300 }
1301 return false;
1302 }
1305 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1306 Klass* klass = const_cast<InstanceKlass*>(this);
1307 while (klass != NULL) {
1308 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1309 return true;
1310 }
1311 klass = klass->super();
1312 }
1313 return false;
1314 }
1317 void InstanceKlass::methods_do(void f(Method* method)) {
1318 int len = methods()->length();
1319 for (int index = 0; index < len; index++) {
1320 Method* m = methods()->at(index);
1321 assert(m->is_method(), "must be method");
1322 f(m);
1323 }
1324 }
1327 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1328 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1329 if (fs.access_flags().is_static()) {
1330 fieldDescriptor& fd = fs.field_descriptor();
1331 cl->do_field(&fd);
1332 }
1333 }
1334 }
1337 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1338 instanceKlassHandle h_this(THREAD, this);
1339 do_local_static_fields_impl(h_this, f, mirror, CHECK);
1340 }
1343 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1344 void f(fieldDescriptor* fd, Handle mirror, TRAPS), Handle mirror, TRAPS) {
1345 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1346 if (fs.access_flags().is_static()) {
1347 fieldDescriptor& fd = fs.field_descriptor();
1348 f(&fd, mirror, CHECK);
1349 }
1350 }
1351 }
1354 static int compare_fields_by_offset(int* a, int* b) {
1355 return a[0] - b[0];
1356 }
1358 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1359 InstanceKlass* super = superklass();
1360 if (super != NULL) {
1361 super->do_nonstatic_fields(cl);
1362 }
1363 fieldDescriptor fd;
1364 int length = java_fields_count();
1365 // In DebugInfo nonstatic fields are sorted by offset.
1366 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1367 int j = 0;
1368 for (int i = 0; i < length; i += 1) {
1369 fd.reinitialize(this, i);
1370 if (!fd.is_static()) {
1371 fields_sorted[j + 0] = fd.offset();
1372 fields_sorted[j + 1] = i;
1373 j += 2;
1374 }
1375 }
1376 if (j > 0) {
1377 length = j;
1378 // _sort_Fn is defined in growableArray.hpp.
1379 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1380 for (int i = 0; i < length; i += 2) {
1381 fd.reinitialize(this, fields_sorted[i + 1]);
1382 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1383 cl->do_field(&fd);
1384 }
1385 }
1386 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1387 }
1390 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1391 if (array_klasses() != NULL)
1392 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1393 }
1395 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1396 if (array_klasses() != NULL)
1397 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1398 }
1400 #ifdef ASSERT
1401 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1402 int len = methods->length();
1403 for (int index = 0; index < len; index++) {
1404 Method* m = methods->at(index);
1405 assert(m->is_method(), "must be method");
1406 if (m->signature() == signature && m->name() == name) {
1407 return index;
1408 }
1409 }
1410 return -1;
1411 }
1412 #endif
1414 static int binary_search(Array<Method*>* methods, Symbol* name) {
1415 int len = methods->length();
1416 // methods are sorted, so do binary search
1417 int l = 0;
1418 int h = len - 1;
1419 while (l <= h) {
1420 int mid = (l + h) >> 1;
1421 Method* m = methods->at(mid);
1422 assert(m->is_method(), "must be method");
1423 int res = m->name()->fast_compare(name);
1424 if (res == 0) {
1425 return mid;
1426 } else if (res < 0) {
1427 l = mid + 1;
1428 } else {
1429 h = mid - 1;
1430 }
1431 }
1432 return -1;
1433 }
1435 // find_method looks up the name/signature in the local methods array
1436 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1437 return find_method_impl(name, signature, false);
1438 }
1440 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const {
1441 return InstanceKlass::find_method_impl(methods(), name, signature, skipping_overpass);
1442 }
1444 // find_instance_method looks up the name/signature in the local methods array
1445 // and skips over static methods
1446 Method* InstanceKlass::find_instance_method(
1447 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1448 Method* meth = InstanceKlass::find_method(methods, name, signature);
1449 if (meth != NULL && meth->is_static()) {
1450 meth = NULL;
1451 }
1452 return meth;
1453 }
1455 // find_method looks up the name/signature in the local methods array
1456 Method* InstanceKlass::find_method(
1457 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1458 return InstanceKlass::find_method_impl(methods, name, signature, false);
1459 }
1461 Method* InstanceKlass::find_method_impl(
1462 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1463 int hit = find_method_index(methods, name, signature, skipping_overpass);
1464 return hit >= 0 ? methods->at(hit): NULL;
1465 }
1467 // Used directly for default_methods to find the index into the
1468 // default_vtable_indices, and indirectly by find_method
1469 // find_method_index looks in the local methods array to return the index
1470 // of the matching name/signature. If, overpass methods are being ignored,
1471 // the search continues to find a potential non-overpass match. This capability
1472 // is important during method resolution to prefer a static method, for example,
1473 // over an overpass method.
1474 int InstanceKlass::find_method_index(
1475 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1476 int hit = binary_search(methods, name);
1477 if (hit != -1) {
1478 Method* m = methods->at(hit);
1479 // Do linear search to find matching signature. First, quick check
1480 // for common case, ignoring overpasses if requested.
1481 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return hit;
1483 // search downwards through overloaded methods
1484 int i;
1485 for (i = hit - 1; i >= 0; --i) {
1486 Method* m = methods->at(i);
1487 assert(m->is_method(), "must be method");
1488 if (m->name() != name) break;
1489 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1490 }
1491 // search upwards
1492 for (i = hit + 1; i < methods->length(); ++i) {
1493 Method* m = methods->at(i);
1494 assert(m->is_method(), "must be method");
1495 if (m->name() != name) break;
1496 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1497 }
1498 // not found
1499 #ifdef ASSERT
1500 int index = skipping_overpass ? -1 : linear_search(methods, name, signature);
1501 assert(index == -1, err_msg("binary search should have found entry %d", index));
1502 #endif
1503 }
1504 return -1;
1505 }
1506 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1507 return find_method_by_name(methods(), name, end);
1508 }
1510 int InstanceKlass::find_method_by_name(
1511 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1512 assert(end_ptr != NULL, "just checking");
1513 int start = binary_search(methods, name);
1514 int end = start + 1;
1515 if (start != -1) {
1516 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1517 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1518 *end_ptr = end;
1519 return start;
1520 }
1521 return -1;
1522 }
1524 // uncached_lookup_method searches both the local class methods array and all
1525 // superclasses methods arrays, skipping any overpass methods in superclasses.
1526 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const {
1527 MethodLookupMode lookup_mode = mode;
1528 Klass* klass = const_cast<InstanceKlass*>(this);
1529 while (klass != NULL) {
1530 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, (lookup_mode == skip_overpass));
1531 if (method != NULL) {
1532 return method;
1533 }
1534 klass = InstanceKlass::cast(klass)->super();
1535 lookup_mode = skip_overpass; // Always ignore overpass methods in superclasses
1536 }
1537 return NULL;
1538 }
1540 // lookup a method in the default methods list then in all transitive interfaces
1541 // Do NOT return private or static methods
1542 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1543 Symbol* signature) const {
1544 Method* m = NULL;
1545 if (default_methods() != NULL) {
1546 m = find_method(default_methods(), name, signature);
1547 }
1548 // Look up interfaces
1549 if (m == NULL) {
1550 m = lookup_method_in_all_interfaces(name, signature, normal);
1551 }
1552 return m;
1553 }
1555 // lookup a method in all the interfaces that this class implements
1556 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1557 // They should only be found in the initial InterfaceMethodRef
1558 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1559 Symbol* signature,
1560 MethodLookupMode mode) const {
1561 Array<Klass*>* all_ifs = transitive_interfaces();
1562 int num_ifs = all_ifs->length();
1563 InstanceKlass *ik = NULL;
1564 for (int i = 0; i < num_ifs; i++) {
1565 ik = InstanceKlass::cast(all_ifs->at(i));
1566 Method* m = ik->lookup_method(name, signature);
1567 if (m != NULL && m->is_public() && !m->is_static() &&
1568 ((mode != skip_defaults) || !m->is_default_method())) {
1569 return m;
1570 }
1571 }
1572 return NULL;
1573 }
1575 /* jni_id_for_impl for jfieldIds only */
1576 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1577 MutexLocker ml(JfieldIdCreation_lock);
1578 // Retry lookup after we got the lock
1579 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1580 if (probe == NULL) {
1581 // Slow case, allocate new static field identifier
1582 probe = new JNIid(this_oop(), offset, this_oop->jni_ids());
1583 this_oop->set_jni_ids(probe);
1584 }
1585 return probe;
1586 }
1589 /* jni_id_for for jfieldIds only */
1590 JNIid* InstanceKlass::jni_id_for(int offset) {
1591 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1592 if (probe == NULL) {
1593 probe = jni_id_for_impl(this, offset);
1594 }
1595 return probe;
1596 }
1598 u2 InstanceKlass::enclosing_method_data(int offset) {
1599 Array<jushort>* inner_class_list = inner_classes();
1600 if (inner_class_list == NULL) {
1601 return 0;
1602 }
1603 int length = inner_class_list->length();
1604 if (length % inner_class_next_offset == 0) {
1605 return 0;
1606 } else {
1607 int index = length - enclosing_method_attribute_size;
1608 assert(offset < enclosing_method_attribute_size, "invalid offset");
1609 return inner_class_list->at(index + offset);
1610 }
1611 }
1613 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1614 u2 method_index) {
1615 Array<jushort>* inner_class_list = inner_classes();
1616 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1617 int length = inner_class_list->length();
1618 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1619 int index = length - enclosing_method_attribute_size;
1620 inner_class_list->at_put(
1621 index + enclosing_method_class_index_offset, class_index);
1622 inner_class_list->at_put(
1623 index + enclosing_method_method_index_offset, method_index);
1624 }
1625 }
1627 // Lookup or create a jmethodID.
1628 // This code is called by the VMThread and JavaThreads so the
1629 // locking has to be done very carefully to avoid deadlocks
1630 // and/or other cache consistency problems.
1631 //
1632 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1633 size_t idnum = (size_t)method_h->method_idnum();
1634 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1635 size_t length = 0;
1636 jmethodID id = NULL;
1638 // We use a double-check locking idiom here because this cache is
1639 // performance sensitive. In the normal system, this cache only
1640 // transitions from NULL to non-NULL which is safe because we use
1641 // release_set_methods_jmethod_ids() to advertise the new cache.
1642 // A partially constructed cache should never be seen by a racing
1643 // thread. We also use release_store_ptr() to save a new jmethodID
1644 // in the cache so a partially constructed jmethodID should never be
1645 // seen either. Cache reads of existing jmethodIDs proceed without a
1646 // lock, but cache writes of a new jmethodID requires uniqueness and
1647 // creation of the cache itself requires no leaks so a lock is
1648 // generally acquired in those two cases.
1649 //
1650 // If the RedefineClasses() API has been used, then this cache can
1651 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1652 // Cache creation requires no leaks and we require safety between all
1653 // cache accesses and freeing of the old cache so a lock is generally
1654 // acquired when the RedefineClasses() API has been used.
1656 if (jmeths != NULL) {
1657 // the cache already exists
1658 if (!ik_h->idnum_can_increment()) {
1659 // the cache can't grow so we can just get the current values
1660 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1661 } else {
1662 // cache can grow so we have to be more careful
1663 if (Threads::number_of_threads() == 0 ||
1664 SafepointSynchronize::is_at_safepoint()) {
1665 // we're single threaded or at a safepoint - no locking needed
1666 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1667 } else {
1668 MutexLocker ml(JmethodIdCreation_lock);
1669 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1670 }
1671 }
1672 }
1673 // implied else:
1674 // we need to allocate a cache so default length and id values are good
1676 if (jmeths == NULL || // no cache yet
1677 length <= idnum || // cache is too short
1678 id == NULL) { // cache doesn't contain entry
1680 // This function can be called by the VMThread so we have to do all
1681 // things that might block on a safepoint before grabbing the lock.
1682 // Otherwise, we can deadlock with the VMThread or have a cache
1683 // consistency issue. These vars keep track of what we might have
1684 // to free after the lock is dropped.
1685 jmethodID to_dealloc_id = NULL;
1686 jmethodID* to_dealloc_jmeths = NULL;
1688 // may not allocate new_jmeths or use it if we allocate it
1689 jmethodID* new_jmeths = NULL;
1690 if (length <= idnum) {
1691 // allocate a new cache that might be used
1692 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1693 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1694 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1695 // cache size is stored in element[0], other elements offset by one
1696 new_jmeths[0] = (jmethodID)size;
1697 }
1699 // allocate a new jmethodID that might be used
1700 jmethodID new_id = NULL;
1701 if (method_h->is_old() && !method_h->is_obsolete()) {
1702 // The method passed in is old (but not obsolete), we need to use the current version
1703 Method* current_method = ik_h->method_with_idnum((int)idnum);
1704 assert(current_method != NULL, "old and but not obsolete, so should exist");
1705 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1706 } else {
1707 // It is the current version of the method or an obsolete method,
1708 // use the version passed in
1709 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1710 }
1712 if (Threads::number_of_threads() == 0 ||
1713 SafepointSynchronize::is_at_safepoint()) {
1714 // we're single threaded or at a safepoint - no locking needed
1715 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1716 &to_dealloc_id, &to_dealloc_jmeths);
1717 } else {
1718 MutexLocker ml(JmethodIdCreation_lock);
1719 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1720 &to_dealloc_id, &to_dealloc_jmeths);
1721 }
1723 // The lock has been dropped so we can free resources.
1724 // Free up either the old cache or the new cache if we allocated one.
1725 if (to_dealloc_jmeths != NULL) {
1726 FreeHeap(to_dealloc_jmeths);
1727 }
1728 // free up the new ID since it wasn't needed
1729 if (to_dealloc_id != NULL) {
1730 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1731 }
1732 }
1733 return id;
1734 }
1737 // Common code to fetch the jmethodID from the cache or update the
1738 // cache with the new jmethodID. This function should never do anything
1739 // that causes the caller to go to a safepoint or we can deadlock with
1740 // the VMThread or have cache consistency issues.
1741 //
1742 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1743 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1744 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1745 jmethodID** to_dealloc_jmeths_p) {
1746 assert(new_id != NULL, "sanity check");
1747 assert(to_dealloc_id_p != NULL, "sanity check");
1748 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1749 assert(Threads::number_of_threads() == 0 ||
1750 SafepointSynchronize::is_at_safepoint() ||
1751 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1753 // reacquire the cache - we are locked, single threaded or at a safepoint
1754 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1755 jmethodID id = NULL;
1756 size_t length = 0;
1758 if (jmeths == NULL || // no cache yet
1759 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1760 if (jmeths != NULL) {
1761 // copy any existing entries from the old cache
1762 for (size_t index = 0; index < length; index++) {
1763 new_jmeths[index+1] = jmeths[index+1];
1764 }
1765 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1766 }
1767 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1768 } else {
1769 // fetch jmethodID (if any) from the existing cache
1770 id = jmeths[idnum+1];
1771 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1772 }
1773 if (id == NULL) {
1774 // No matching jmethodID in the existing cache or we have a new
1775 // cache or we just grew the cache. This cache write is done here
1776 // by the first thread to win the foot race because a jmethodID
1777 // needs to be unique once it is generally available.
1778 id = new_id;
1780 // The jmethodID cache can be read while unlocked so we have to
1781 // make sure the new jmethodID is complete before installing it
1782 // in the cache.
1783 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1784 } else {
1785 *to_dealloc_id_p = new_id; // save new id for later delete
1786 }
1787 return id;
1788 }
1791 // Common code to get the jmethodID cache length and the jmethodID
1792 // value at index idnum if there is one.
1793 //
1794 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1795 size_t idnum, size_t *length_p, jmethodID* id_p) {
1796 assert(cache != NULL, "sanity check");
1797 assert(length_p != NULL, "sanity check");
1798 assert(id_p != NULL, "sanity check");
1800 // cache size is stored in element[0], other elements offset by one
1801 *length_p = (size_t)cache[0];
1802 if (*length_p <= idnum) { // cache is too short
1803 *id_p = NULL;
1804 } else {
1805 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1806 }
1807 }
1810 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1811 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1812 size_t idnum = (size_t)method->method_idnum();
1813 jmethodID* jmeths = methods_jmethod_ids_acquire();
1814 size_t length; // length assigned as debugging crumb
1815 jmethodID id = NULL;
1816 if (jmeths != NULL && // If there is a cache
1817 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1818 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1819 }
1820 return id;
1821 }
1823 int nmethodBucket::decrement() {
1824 return Atomic::add(-1, (volatile int *)&_count);
1825 }
1827 //
1828 // Walk the list of dependent nmethods searching for nmethods which
1829 // are dependent on the changes that were passed in and mark them for
1830 // deoptimization. Returns the number of nmethods found.
1831 //
1832 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1833 assert_locked_or_safepoint(CodeCache_lock);
1834 int found = 0;
1835 nmethodBucket* b = _dependencies;
1836 while (b != NULL) {
1837 nmethod* nm = b->get_nmethod();
1838 // since dependencies aren't removed until an nmethod becomes a zombie,
1839 // the dependency list may contain nmethods which aren't alive.
1840 if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1841 if (TraceDependencies) {
1842 ResourceMark rm;
1843 tty->print_cr("Marked for deoptimization");
1844 tty->print_cr(" context = %s", this->external_name());
1845 changes.print();
1846 nm->print();
1847 nm->print_dependencies();
1848 }
1849 nm->mark_for_deoptimization();
1850 found++;
1851 }
1852 b = b->next();
1853 }
1854 return found;
1855 }
1857 void InstanceKlass::clean_dependent_nmethods() {
1858 assert_locked_or_safepoint(CodeCache_lock);
1860 if (has_unloaded_dependent()) {
1861 nmethodBucket* b = _dependencies;
1862 nmethodBucket* last = NULL;
1863 while (b != NULL) {
1864 assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
1866 nmethodBucket* next = b->next();
1868 if (b->count() == 0) {
1869 if (last == NULL) {
1870 _dependencies = next;
1871 } else {
1872 last->set_next(next);
1873 }
1874 delete b;
1875 // last stays the same.
1876 } else {
1877 last = b;
1878 }
1880 b = next;
1881 }
1882 set_has_unloaded_dependent(false);
1883 }
1884 #ifdef ASSERT
1885 else {
1886 // Verification
1887 for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) {
1888 assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
1889 assert(b->count() != 0, "empty buckets need to be cleaned");
1890 }
1891 }
1892 #endif
1893 }
1895 //
1896 // Add an nmethodBucket to the list of dependencies for this nmethod.
1897 // It's possible that an nmethod has multiple dependencies on this klass
1898 // so a count is kept for each bucket to guarantee that creation and
1899 // deletion of dependencies is consistent.
1900 //
1901 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1902 assert_locked_or_safepoint(CodeCache_lock);
1903 nmethodBucket* b = _dependencies;
1904 nmethodBucket* last = NULL;
1905 while (b != NULL) {
1906 if (nm == b->get_nmethod()) {
1907 b->increment();
1908 return;
1909 }
1910 b = b->next();
1911 }
1912 _dependencies = new nmethodBucket(nm, _dependencies);
1913 }
1916 //
1917 // Decrement count of the nmethod in the dependency list and remove
1918 // the bucket competely when the count goes to 0. This method must
1919 // find a corresponding bucket otherwise there's a bug in the
1920 // recording of dependecies.
1921 //
1922 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1923 assert_locked_or_safepoint(CodeCache_lock);
1924 nmethodBucket* b = _dependencies;
1925 nmethodBucket* last = NULL;
1926 while (b != NULL) {
1927 if (nm == b->get_nmethod()) {
1928 int val = b->decrement();
1929 guarantee(val >= 0, err_msg("Underflow: %d", val));
1930 if (val == 0) {
1931 set_has_unloaded_dependent(true);
1932 }
1933 return;
1934 }
1935 last = b;
1936 b = b->next();
1937 }
1938 #ifdef ASSERT
1939 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1940 nm->print();
1941 #endif // ASSERT
1942 ShouldNotReachHere();
1943 }
1946 #ifndef PRODUCT
1947 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1948 nmethodBucket* b = _dependencies;
1949 int idx = 0;
1950 while (b != NULL) {
1951 nmethod* nm = b->get_nmethod();
1952 tty->print("[%d] count=%d { ", idx++, b->count());
1953 if (!verbose) {
1954 nm->print_on(tty, "nmethod");
1955 tty->print_cr(" } ");
1956 } else {
1957 nm->print();
1958 nm->print_dependencies();
1959 tty->print_cr("--- } ");
1960 }
1961 b = b->next();
1962 }
1963 }
1966 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1967 nmethodBucket* b = _dependencies;
1968 while (b != NULL) {
1969 if (nm == b->get_nmethod()) {
1970 #ifdef ASSERT
1971 int count = b->count();
1972 assert(count >= 0, "Just check if we ever get here 1");
1973 assert(count > 0, "Just check if we ever get here 2");
1974 #endif
1975 return true;
1976 }
1977 b = b->next();
1978 }
1979 return false;
1980 }
1981 #endif //PRODUCT
1984 // Garbage collection
1986 #ifdef ASSERT
1987 template <class T> void assert_is_in(T *p) {
1988 T heap_oop = oopDesc::load_heap_oop(p);
1989 if (!oopDesc::is_null(heap_oop)) {
1990 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1991 assert(Universe::heap()->is_in(o), "should be in heap");
1992 }
1993 }
1994 template <class T> void assert_is_in_closed_subset(T *p) {
1995 T heap_oop = oopDesc::load_heap_oop(p);
1996 if (!oopDesc::is_null(heap_oop)) {
1997 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1998 assert(Universe::heap()->is_in_closed_subset(o),
1999 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
2000 }
2001 }
2002 template <class T> void assert_is_in_reserved(T *p) {
2003 T heap_oop = oopDesc::load_heap_oop(p);
2004 if (!oopDesc::is_null(heap_oop)) {
2005 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
2006 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
2007 }
2008 }
2009 template <class T> void assert_nothing(T *p) {}
2011 #else
2012 template <class T> void assert_is_in(T *p) {}
2013 template <class T> void assert_is_in_closed_subset(T *p) {}
2014 template <class T> void assert_is_in_reserved(T *p) {}
2015 template <class T> void assert_nothing(T *p) {}
2016 #endif // ASSERT
2018 //
2019 // Macros that iterate over areas of oops which are specialized on type of
2020 // oop pointer either narrow or wide, depending on UseCompressedOops
2021 //
2022 // Parameters are:
2023 // T - type of oop to point to (either oop or narrowOop)
2024 // start_p - starting pointer for region to iterate over
2025 // count - number of oops or narrowOops to iterate over
2026 // do_oop - action to perform on each oop (it's arbitrary C code which
2027 // makes it more efficient to put in a macro rather than making
2028 // it a template function)
2029 // assert_fn - assert function which is template function because performance
2030 // doesn't matter when enabled.
2031 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
2032 T, start_p, count, do_oop, \
2033 assert_fn) \
2034 { \
2035 T* p = (T*)(start_p); \
2036 T* const end = p + (count); \
2037 while (p < end) { \
2038 (assert_fn)(p); \
2039 do_oop; \
2040 ++p; \
2041 } \
2042 }
2044 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
2045 T, start_p, count, do_oop, \
2046 assert_fn) \
2047 { \
2048 T* const start = (T*)(start_p); \
2049 T* p = start + (count); \
2050 while (start < p) { \
2051 --p; \
2052 (assert_fn)(p); \
2053 do_oop; \
2054 } \
2055 }
2057 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
2058 T, start_p, count, low, high, \
2059 do_oop, assert_fn) \
2060 { \
2061 T* const l = (T*)(low); \
2062 T* const h = (T*)(high); \
2063 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
2064 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
2065 "bounded region must be properly aligned"); \
2066 T* p = (T*)(start_p); \
2067 T* end = p + (count); \
2068 if (p < l) p = l; \
2069 if (end > h) end = h; \
2070 while (p < end) { \
2071 (assert_fn)(p); \
2072 do_oop; \
2073 ++p; \
2074 } \
2075 }
2078 // The following macros call specialized macros, passing either oop or
2079 // narrowOop as the specialization type. These test the UseCompressedOops
2080 // flag.
2081 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
2082 { \
2083 /* Compute oopmap block range. The common case \
2084 is nonstatic_oop_map_size == 1. */ \
2085 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2086 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2087 if (UseCompressedOops) { \
2088 while (map < end_map) { \
2089 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
2090 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2091 do_oop, assert_fn) \
2092 ++map; \
2093 } \
2094 } else { \
2095 while (map < end_map) { \
2096 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
2097 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2098 do_oop, assert_fn) \
2099 ++map; \
2100 } \
2101 } \
2102 }
2104 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
2105 { \
2106 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
2107 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
2108 if (UseCompressedOops) { \
2109 while (start_map < map) { \
2110 --map; \
2111 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
2112 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2113 do_oop, assert_fn) \
2114 } \
2115 } else { \
2116 while (start_map < map) { \
2117 --map; \
2118 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
2119 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2120 do_oop, assert_fn) \
2121 } \
2122 } \
2123 }
2125 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
2126 assert_fn) \
2127 { \
2128 /* Compute oopmap block range. The common case is \
2129 nonstatic_oop_map_size == 1, so we accept the \
2130 usually non-existent extra overhead of examining \
2131 all the maps. */ \
2132 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2133 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2134 if (UseCompressedOops) { \
2135 while (map < end_map) { \
2136 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
2137 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2138 low, high, \
2139 do_oop, assert_fn) \
2140 ++map; \
2141 } \
2142 } else { \
2143 while (map < end_map) { \
2144 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2145 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2146 low, high, \
2147 do_oop, assert_fn) \
2148 ++map; \
2149 } \
2150 } \
2151 }
2153 void InstanceKlass::oop_follow_contents(oop obj) {
2154 assert(obj != NULL, "can't follow the content of NULL object");
2155 MarkSweep::follow_klass(obj->klass());
2156 InstanceKlass_OOP_MAP_ITERATE( \
2157 obj, \
2158 MarkSweep::mark_and_push(p), \
2159 assert_is_in_closed_subset)
2160 }
2162 #if INCLUDE_ALL_GCS
2163 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2164 oop obj) {
2165 assert(obj != NULL, "can't follow the content of NULL object");
2166 PSParallelCompact::follow_klass(cm, obj->klass());
2167 // Only mark the header and let the scan of the meta-data mark
2168 // everything else.
2169 InstanceKlass_OOP_MAP_ITERATE( \
2170 obj, \
2171 PSParallelCompact::mark_and_push(cm, p), \
2172 assert_is_in)
2173 }
2174 #endif // INCLUDE_ALL_GCS
2176 // closure's do_metadata() method dictates whether the given closure should be
2177 // applied to the klass ptr in the object header.
2179 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2180 \
2181 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2182 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2183 /* header */ \
2184 if_do_metadata_checked(closure, nv_suffix) { \
2185 closure->do_klass##nv_suffix(obj->klass()); \
2186 } \
2187 InstanceKlass_OOP_MAP_ITERATE( \
2188 obj, \
2189 SpecializationStats:: \
2190 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2191 (closure)->do_oop##nv_suffix(p), \
2192 assert_is_in_closed_subset) \
2193 return size_helper(); \
2194 }
2196 #if INCLUDE_ALL_GCS
2197 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2198 \
2199 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2200 OopClosureType* closure) { \
2201 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2202 \
2203 assert_should_ignore_metadata(closure, nv_suffix); \
2204 \
2205 /* instance variables */ \
2206 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2207 obj, \
2208 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2209 (closure)->do_oop##nv_suffix(p), \
2210 assert_is_in_closed_subset) \
2211 return size_helper(); \
2212 }
2213 #endif // INCLUDE_ALL_GCS
2215 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2216 \
2217 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2218 OopClosureType* closure, \
2219 MemRegion mr) { \
2220 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2221 if_do_metadata_checked(closure, nv_suffix) { \
2222 if (mr.contains(obj)) { \
2223 closure->do_klass##nv_suffix(obj->klass()); \
2224 } \
2225 } \
2226 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2227 obj, mr.start(), mr.end(), \
2228 (closure)->do_oop##nv_suffix(p), \
2229 assert_is_in_closed_subset) \
2230 return size_helper(); \
2231 }
2233 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2234 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2235 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2236 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2237 #if INCLUDE_ALL_GCS
2238 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2239 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2240 #endif // INCLUDE_ALL_GCS
2242 int InstanceKlass::oop_adjust_pointers(oop obj) {
2243 int size = size_helper();
2244 InstanceKlass_OOP_MAP_ITERATE( \
2245 obj, \
2246 MarkSweep::adjust_pointer(p), \
2247 assert_is_in)
2248 return size;
2249 }
2251 #if INCLUDE_ALL_GCS
2252 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2253 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2254 obj, \
2255 if (PSScavenge::should_scavenge(p)) { \
2256 pm->claim_or_forward_depth(p); \
2257 }, \
2258 assert_nothing )
2259 }
2261 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2262 int size = size_helper();
2263 InstanceKlass_OOP_MAP_ITERATE( \
2264 obj, \
2265 PSParallelCompact::adjust_pointer(p), \
2266 assert_is_in)
2267 return size;
2268 }
2270 #endif // INCLUDE_ALL_GCS
2272 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2273 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2274 if (is_interface()) {
2275 if (ClassUnloading) {
2276 Klass* impl = implementor();
2277 if (impl != NULL) {
2278 if (!impl->is_loader_alive(is_alive)) {
2279 // remove this guy
2280 Klass** klass = adr_implementor();
2281 assert(klass != NULL, "null klass");
2282 if (klass != NULL) {
2283 *klass = NULL;
2284 }
2285 }
2286 }
2287 }
2288 }
2289 }
2291 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2292 for (int m = 0; m < methods()->length(); m++) {
2293 MethodData* mdo = methods()->at(m)->method_data();
2294 if (mdo != NULL) {
2295 mdo->clean_method_data(is_alive);
2296 }
2297 }
2298 }
2301 static void remove_unshareable_in_class(Klass* k) {
2302 // remove klass's unshareable info
2303 k->remove_unshareable_info();
2304 }
2306 void InstanceKlass::remove_unshareable_info() {
2307 Klass::remove_unshareable_info();
2308 // Unlink the class
2309 if (is_linked()) {
2310 unlink_class();
2311 }
2312 init_implementor();
2314 constants()->remove_unshareable_info();
2316 for (int i = 0; i < methods()->length(); i++) {
2317 Method* m = methods()->at(i);
2318 m->remove_unshareable_info();
2319 }
2321 // do array classes also.
2322 array_klasses_do(remove_unshareable_in_class);
2323 }
2325 void restore_unshareable_in_class(Klass* k, TRAPS) {
2326 k->restore_unshareable_info(CHECK);
2327 }
2329 void InstanceKlass::restore_unshareable_info(TRAPS) {
2330 Klass::restore_unshareable_info(CHECK);
2331 instanceKlassHandle ik(THREAD, this);
2333 Array<Method*>* methods = ik->methods();
2334 int num_methods = methods->length();
2335 for (int index2 = 0; index2 < num_methods; ++index2) {
2336 methodHandle m(THREAD, methods->at(index2));
2337 m->restore_unshareable_info(CHECK);
2338 }
2339 if (JvmtiExport::has_redefined_a_class()) {
2340 // Reinitialize vtable because RedefineClasses may have changed some
2341 // entries in this vtable for super classes so the CDS vtable might
2342 // point to old or obsolete entries. RedefineClasses doesn't fix up
2343 // vtables in the shared system dictionary, only the main one.
2344 // It also redefines the itable too so fix that too.
2345 ResourceMark rm(THREAD);
2346 ik->vtable()->initialize_vtable(false, CHECK);
2347 ik->itable()->initialize_itable(false, CHECK);
2348 }
2350 // restore constant pool resolved references
2351 ik->constants()->restore_unshareable_info(CHECK);
2353 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2354 }
2356 static void clear_all_breakpoints(Method* m) {
2357 m->clear_all_breakpoints();
2358 }
2361 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2362 // notify the debugger
2363 if (JvmtiExport::should_post_class_unload()) {
2364 JvmtiExport::post_class_unload(ik);
2365 }
2367 // notify ClassLoadingService of class unload
2368 ClassLoadingService::notify_class_unloaded(ik);
2369 }
2371 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2372 // Clean up C heap
2373 ik->release_C_heap_structures();
2374 ik->constants()->release_C_heap_structures();
2375 }
2377 void InstanceKlass::release_C_heap_structures() {
2379 // Can't release the constant pool here because the constant pool can be
2380 // deallocated separately from the InstanceKlass for default methods and
2381 // redefine classes.
2383 // Deallocate oop map cache
2384 if (_oop_map_cache != NULL) {
2385 delete _oop_map_cache;
2386 _oop_map_cache = NULL;
2387 }
2389 // Deallocate JNI identifiers for jfieldIDs
2390 JNIid::deallocate(jni_ids());
2391 set_jni_ids(NULL);
2393 jmethodID* jmeths = methods_jmethod_ids_acquire();
2394 if (jmeths != (jmethodID*)NULL) {
2395 release_set_methods_jmethod_ids(NULL);
2396 FreeHeap(jmeths);
2397 }
2399 // Deallocate MemberNameTable
2400 {
2401 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2402 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2403 MemberNameTable* mnt = member_names();
2404 if (mnt != NULL) {
2405 delete mnt;
2406 set_member_names(NULL);
2407 }
2408 }
2410 // release dependencies
2411 nmethodBucket* b = _dependencies;
2412 _dependencies = NULL;
2413 while (b != NULL) {
2414 nmethodBucket* next = b->next();
2415 delete b;
2416 b = next;
2417 }
2419 // Deallocate breakpoint records
2420 if (breakpoints() != 0x0) {
2421 methods_do(clear_all_breakpoints);
2422 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2423 }
2425 // deallocate information about previous versions
2426 if (_previous_versions != NULL) {
2427 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2428 PreviousVersionNode * pv_node = _previous_versions->at(i);
2429 delete pv_node;
2430 }
2431 delete _previous_versions;
2432 _previous_versions = NULL;
2433 }
2435 // deallocate the cached class file
2436 if (_cached_class_file != NULL) {
2437 os::free(_cached_class_file, mtClass);
2438 _cached_class_file = NULL;
2439 }
2441 // Decrement symbol reference counts associated with the unloaded class.
2442 if (_name != NULL) _name->decrement_refcount();
2443 // unreference array name derived from this class name (arrays of an unloaded
2444 // class can't be referenced anymore).
2445 if (_array_name != NULL) _array_name->decrement_refcount();
2446 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2448 assert(_total_instanceKlass_count >= 1, "Sanity check");
2449 Atomic::dec(&_total_instanceKlass_count);
2450 }
2452 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2453 if (array == NULL) {
2454 _source_debug_extension = NULL;
2455 } else {
2456 // Adding one to the attribute length in order to store a null terminator
2457 // character could cause an overflow because the attribute length is
2458 // already coded with an u4 in the classfile, but in practice, it's
2459 // unlikely to happen.
2460 assert((length+1) > length, "Overflow checking");
2461 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2462 for (int i = 0; i < length; i++) {
2463 sde[i] = array[i];
2464 }
2465 sde[length] = '\0';
2466 _source_debug_extension = sde;
2467 }
2468 }
2470 address InstanceKlass::static_field_addr(int offset) {
2471 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2472 }
2475 const char* InstanceKlass::signature_name() const {
2476 int hash_len = 0;
2477 char hash_buf[40];
2479 // If this is an anonymous class, append a hash to make the name unique
2480 if (is_anonymous()) {
2481 assert(EnableInvokeDynamic, "EnableInvokeDynamic was not set.");
2482 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2483 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
2484 hash_len = (int)strlen(hash_buf);
2485 }
2487 // Get the internal name as a c string
2488 const char* src = (const char*) (name()->as_C_string());
2489 const int src_length = (int)strlen(src);
2491 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2493 // Add L as type indicator
2494 int dest_index = 0;
2495 dest[dest_index++] = 'L';
2497 // Add the actual class name
2498 for (int src_index = 0; src_index < src_length; ) {
2499 dest[dest_index++] = src[src_index++];
2500 }
2502 // If we have a hash, append it
2503 for (int hash_index = 0; hash_index < hash_len; ) {
2504 dest[dest_index++] = hash_buf[hash_index++];
2505 }
2507 // Add the semicolon and the NULL
2508 dest[dest_index++] = ';';
2509 dest[dest_index] = '\0';
2510 return dest;
2511 }
2513 // different verisons of is_same_class_package
2514 bool InstanceKlass::is_same_class_package(Klass* class2) {
2515 Klass* class1 = this;
2516 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2517 Symbol* classname1 = class1->name();
2519 if (class2->oop_is_objArray()) {
2520 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2521 }
2522 oop classloader2;
2523 if (class2->oop_is_instance()) {
2524 classloader2 = InstanceKlass::cast(class2)->class_loader();
2525 } else {
2526 assert(class2->oop_is_typeArray(), "should be type array");
2527 classloader2 = NULL;
2528 }
2529 Symbol* classname2 = class2->name();
2531 return InstanceKlass::is_same_class_package(classloader1, classname1,
2532 classloader2, classname2);
2533 }
2535 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2536 Klass* class1 = this;
2537 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2538 Symbol* classname1 = class1->name();
2540 return InstanceKlass::is_same_class_package(classloader1, classname1,
2541 classloader2, classname2);
2542 }
2544 // return true if two classes are in the same package, classloader
2545 // and classname information is enough to determine a class's package
2546 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2547 oop class_loader2, Symbol* class_name2) {
2548 if (class_loader1 != class_loader2) {
2549 return false;
2550 } else if (class_name1 == class_name2) {
2551 return true; // skip painful bytewise comparison
2552 } else {
2553 ResourceMark rm;
2555 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2556 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2557 // Otherwise, we just compare jbyte values between the strings.
2558 const jbyte *name1 = class_name1->base();
2559 const jbyte *name2 = class_name2->base();
2561 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2562 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2564 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2565 // One of the two doesn't have a package. Only return true
2566 // if the other one also doesn't have a package.
2567 return last_slash1 == last_slash2;
2568 } else {
2569 // Skip over '['s
2570 if (*name1 == '[') {
2571 do {
2572 name1++;
2573 } while (*name1 == '[');
2574 if (*name1 != 'L') {
2575 // Something is terribly wrong. Shouldn't be here.
2576 return false;
2577 }
2578 }
2579 if (*name2 == '[') {
2580 do {
2581 name2++;
2582 } while (*name2 == '[');
2583 if (*name2 != 'L') {
2584 // Something is terribly wrong. Shouldn't be here.
2585 return false;
2586 }
2587 }
2589 // Check that package part is identical
2590 int length1 = last_slash1 - name1;
2591 int length2 = last_slash2 - name2;
2593 return UTF8::equal(name1, length1, name2, length2);
2594 }
2595 }
2596 }
2598 // Returns true iff super_method can be overridden by a method in targetclassname
2599 // See JSL 3rd edition 8.4.6.1
2600 // Assumes name-signature match
2601 // "this" is InstanceKlass of super_method which must exist
2602 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2603 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2604 // Private methods can not be overridden
2605 if (super_method->is_private()) {
2606 return false;
2607 }
2608 // If super method is accessible, then override
2609 if ((super_method->is_protected()) ||
2610 (super_method->is_public())) {
2611 return true;
2612 }
2613 // Package-private methods are not inherited outside of package
2614 assert(super_method->is_package_private(), "must be package private");
2615 return(is_same_class_package(targetclassloader(), targetclassname));
2616 }
2618 /* defined for now in jvm.cpp, for historical reasons *--
2619 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2620 Symbol*& simple_name_result, TRAPS) {
2621 ...
2622 }
2623 */
2625 // tell if two classes have the same enclosing class (at package level)
2626 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2627 Klass* class2_oop, TRAPS) {
2628 if (class2_oop == class1()) return true;
2629 if (!class2_oop->oop_is_instance()) return false;
2630 instanceKlassHandle class2(THREAD, class2_oop);
2632 // must be in same package before we try anything else
2633 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2634 return false;
2636 // As long as there is an outer1.getEnclosingClass,
2637 // shift the search outward.
2638 instanceKlassHandle outer1 = class1;
2639 for (;;) {
2640 // As we walk along, look for equalities between outer1 and class2.
2641 // Eventually, the walks will terminate as outer1 stops
2642 // at the top-level class around the original class.
2643 bool ignore_inner_is_member;
2644 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2645 CHECK_false);
2646 if (next == NULL) break;
2647 if (next == class2()) return true;
2648 outer1 = instanceKlassHandle(THREAD, next);
2649 }
2651 // Now do the same for class2.
2652 instanceKlassHandle outer2 = class2;
2653 for (;;) {
2654 bool ignore_inner_is_member;
2655 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2656 CHECK_false);
2657 if (next == NULL) break;
2658 // Might as well check the new outer against all available values.
2659 if (next == class1()) return true;
2660 if (next == outer1()) return true;
2661 outer2 = instanceKlassHandle(THREAD, next);
2662 }
2664 // If by this point we have not found an equality between the
2665 // two classes, we know they are in separate package members.
2666 return false;
2667 }
2670 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2671 jint access = access_flags().as_int();
2673 // But check if it happens to be member class.
2674 instanceKlassHandle ik(THREAD, this);
2675 InnerClassesIterator iter(ik);
2676 for (; !iter.done(); iter.next()) {
2677 int ioff = iter.inner_class_info_index();
2678 // Inner class attribute can be zero, skip it.
2679 // Strange but true: JVM spec. allows null inner class refs.
2680 if (ioff == 0) continue;
2682 // only look at classes that are already loaded
2683 // since we are looking for the flags for our self.
2684 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2685 if ((ik->name() == inner_name)) {
2686 // This is really a member class.
2687 access = iter.inner_access_flags();
2688 break;
2689 }
2690 }
2691 // Remember to strip ACC_SUPER bit
2692 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2693 }
2695 jint InstanceKlass::jvmti_class_status() const {
2696 jint result = 0;
2698 if (is_linked()) {
2699 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2700 }
2702 if (is_initialized()) {
2703 assert(is_linked(), "Class status is not consistent");
2704 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2705 }
2706 if (is_in_error_state()) {
2707 result |= JVMTI_CLASS_STATUS_ERROR;
2708 }
2709 return result;
2710 }
2712 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2713 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2714 int method_table_offset_in_words = ioe->offset()/wordSize;
2715 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2716 / itableOffsetEntry::size();
2718 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2719 // If the interface isn't implemented by the receiver class,
2720 // the VM should throw IncompatibleClassChangeError.
2721 if (cnt >= nof_interfaces) {
2722 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2723 }
2725 Klass* ik = ioe->interface_klass();
2726 if (ik == holder) break;
2727 }
2729 itableMethodEntry* ime = ioe->first_method_entry(this);
2730 Method* m = ime[index].method();
2731 if (m == NULL) {
2732 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2733 }
2734 return m;
2735 }
2738 #if INCLUDE_JVMTI
2739 // update default_methods for redefineclasses for methods that are
2740 // not yet in the vtable due to concurrent subclass define and superinterface
2741 // redefinition
2742 // Note: those in the vtable, should have been updated via adjust_method_entries
2743 void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods,
2744 int methods_length, bool* trace_name_printed) {
2745 // search the default_methods for uses of either obsolete or EMCP methods
2746 if (default_methods() != NULL) {
2747 for (int j = 0; j < methods_length; j++) {
2748 Method* old_method = old_methods[j];
2749 Method* new_method = new_methods[j];
2751 for (int index = 0; index < default_methods()->length(); index ++) {
2752 if (default_methods()->at(index) == old_method) {
2753 default_methods()->at_put(index, new_method);
2754 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2755 if (!(*trace_name_printed)) {
2756 // RC_TRACE_MESG macro has an embedded ResourceMark
2757 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2758 external_name(),
2759 old_method->method_holder()->external_name()));
2760 *trace_name_printed = true;
2761 }
2762 RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2763 new_method->name()->as_C_string(),
2764 new_method->signature()->as_C_string()));
2765 }
2766 }
2767 }
2768 }
2769 }
2770 }
2771 #endif // INCLUDE_JVMTI
2773 // On-stack replacement stuff
2774 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2775 // only one compilation can be active
2776 NEEDS_CLEANUP
2777 // This is a short non-blocking critical region, so the no safepoint check is ok.
2778 OsrList_lock->lock_without_safepoint_check();
2779 assert(n->is_osr_method(), "wrong kind of nmethod");
2780 n->set_osr_link(osr_nmethods_head());
2781 set_osr_nmethods_head(n);
2782 // Raise the highest osr level if necessary
2783 if (TieredCompilation) {
2784 Method* m = n->method();
2785 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2786 }
2787 // Remember to unlock again
2788 OsrList_lock->unlock();
2790 // Get rid of the osr methods for the same bci that have lower levels.
2791 if (TieredCompilation) {
2792 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2793 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2794 if (inv != NULL && inv->is_in_use()) {
2795 inv->make_not_entrant();
2796 }
2797 }
2798 }
2799 }
2802 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2803 // This is a short non-blocking critical region, so the no safepoint check is ok.
2804 OsrList_lock->lock_without_safepoint_check();
2805 assert(n->is_osr_method(), "wrong kind of nmethod");
2806 nmethod* last = NULL;
2807 nmethod* cur = osr_nmethods_head();
2808 int max_level = CompLevel_none; // Find the max comp level excluding n
2809 Method* m = n->method();
2810 // Search for match
2811 while(cur != NULL && cur != n) {
2812 if (TieredCompilation && m == cur->method()) {
2813 // Find max level before n
2814 max_level = MAX2(max_level, cur->comp_level());
2815 }
2816 last = cur;
2817 cur = cur->osr_link();
2818 }
2819 nmethod* next = NULL;
2820 if (cur == n) {
2821 next = cur->osr_link();
2822 if (last == NULL) {
2823 // Remove first element
2824 set_osr_nmethods_head(next);
2825 } else {
2826 last->set_osr_link(next);
2827 }
2828 }
2829 n->set_osr_link(NULL);
2830 if (TieredCompilation) {
2831 cur = next;
2832 while (cur != NULL) {
2833 // Find max level after n
2834 if (m == cur->method()) {
2835 max_level = MAX2(max_level, cur->comp_level());
2836 }
2837 cur = cur->osr_link();
2838 }
2839 m->set_highest_osr_comp_level(max_level);
2840 }
2841 // Remember to unlock again
2842 OsrList_lock->unlock();
2843 }
2845 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2846 // This is a short non-blocking critical region, so the no safepoint check is ok.
2847 OsrList_lock->lock_without_safepoint_check();
2848 nmethod* osr = osr_nmethods_head();
2849 nmethod* best = NULL;
2850 while (osr != NULL) {
2851 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2852 // There can be a time when a c1 osr method exists but we are waiting
2853 // for a c2 version. When c2 completes its osr nmethod we will trash
2854 // the c1 version and only be able to find the c2 version. However
2855 // while we overflow in the c1 code at back branches we don't want to
2856 // try and switch to the same code as we are already running
2858 if (osr->method() == m &&
2859 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2860 if (match_level) {
2861 if (osr->comp_level() == comp_level) {
2862 // Found a match - return it.
2863 OsrList_lock->unlock();
2864 return osr;
2865 }
2866 } else {
2867 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2868 if (osr->comp_level() == CompLevel_highest_tier) {
2869 // Found the best possible - return it.
2870 OsrList_lock->unlock();
2871 return osr;
2872 }
2873 best = osr;
2874 }
2875 }
2876 }
2877 osr = osr->osr_link();
2878 }
2879 OsrList_lock->unlock();
2880 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2881 return best;
2882 }
2883 return NULL;
2884 }
2886 void InstanceKlass::add_member_name(int index, Handle mem_name) {
2887 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2888 MutexLocker ml(MemberNameTable_lock);
2889 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2890 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2892 if (_member_names == NULL) {
2893 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2894 }
2895 _member_names->add_member_name(index, mem_name_wref);
2896 }
2898 oop InstanceKlass::get_member_name(int index) {
2899 MutexLocker ml(MemberNameTable_lock);
2900 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2901 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2903 if (_member_names == NULL) {
2904 return NULL;
2905 }
2906 oop mem_name =_member_names->get_member_name(index);
2907 return mem_name;
2908 }
2910 // -----------------------------------------------------------------------------------------------------
2911 // Printing
2913 #ifndef PRODUCT
2915 #define BULLET " - "
2917 static const char* state_names[] = {
2918 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2919 };
2921 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2922 for (int i = 0; i < len; i++) {
2923 intptr_t e = start[i];
2924 st->print("%d : " INTPTR_FORMAT, i, e);
2925 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2926 st->print(" ");
2927 ((Metadata*)e)->print_value_on(st);
2928 }
2929 st->cr();
2930 }
2931 }
2933 void InstanceKlass::print_on(outputStream* st) const {
2934 assert(is_klass(), "must be klass");
2935 Klass::print_on(st);
2937 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2938 st->print(BULLET"klass size: %d", size()); st->cr();
2939 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2940 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2941 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2942 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2943 st->print(BULLET"sub: ");
2944 Klass* sub = subklass();
2945 int n;
2946 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2947 if (n < MaxSubklassPrintSize) {
2948 sub->print_value_on(st);
2949 st->print(" ");
2950 }
2951 }
2952 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2953 st->cr();
2955 if (is_interface()) {
2956 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2957 if (nof_implementors() == 1) {
2958 st->print_cr(BULLET"implementor: ");
2959 st->print(" ");
2960 implementor()->print_value_on(st);
2961 st->cr();
2962 }
2963 }
2965 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2966 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2967 if (Verbose || WizardMode) {
2968 Array<Method*>* method_array = methods();
2969 for (int i = 0; i < method_array->length(); i++) {
2970 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2971 }
2972 }
2973 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2974 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2975 if (Verbose && default_methods() != NULL) {
2976 Array<Method*>* method_array = default_methods();
2977 for (int i = 0; i < method_array->length(); i++) {
2978 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2979 }
2980 }
2981 if (default_vtable_indices() != NULL) {
2982 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2983 }
2984 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2985 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2986 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2987 if (class_loader_data() != NULL) {
2988 st->print(BULLET"class loader data: ");
2989 class_loader_data()->print_value_on(st);
2990 st->cr();
2991 }
2992 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2993 if (source_file_name() != NULL) {
2994 st->print(BULLET"source file: ");
2995 source_file_name()->print_value_on(st);
2996 st->cr();
2997 }
2998 if (source_debug_extension() != NULL) {
2999 st->print(BULLET"source debug extension: ");
3000 st->print("%s", source_debug_extension());
3001 st->cr();
3002 }
3003 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3004 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3005 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3006 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3007 {
3008 bool have_pv = false;
3009 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
3010 for (PreviousVersionNode * pv_node = pvw.next_previous_version();
3011 pv_node != NULL; pv_node = pvw.next_previous_version()) {
3012 if (!have_pv)
3013 st->print(BULLET"previous version: ");
3014 have_pv = true;
3015 pv_node->prev_constant_pool()->print_value_on(st);
3016 }
3017 if (have_pv) st->cr();
3018 } // pvw is cleaned up
3020 if (generic_signature() != NULL) {
3021 st->print(BULLET"generic signature: ");
3022 generic_signature()->print_value_on(st);
3023 st->cr();
3024 }
3025 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3026 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3027 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
3028 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3029 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
3030 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3031 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3032 FieldPrinter print_static_field(st);
3033 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3034 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3035 FieldPrinter print_nonstatic_field(st);
3036 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
3038 st->print(BULLET"non-static oop maps: ");
3039 OopMapBlock* map = start_of_nonstatic_oop_maps();
3040 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3041 while (map < end_map) {
3042 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3043 map++;
3044 }
3045 st->cr();
3046 }
3048 #endif //PRODUCT
3050 void InstanceKlass::print_value_on(outputStream* st) const {
3051 assert(is_klass(), "must be klass");
3052 if (Verbose || WizardMode) access_flags().print_on(st);
3053 name()->print_value_on(st);
3054 }
3056 #ifndef PRODUCT
3058 void FieldPrinter::do_field(fieldDescriptor* fd) {
3059 _st->print(BULLET);
3060 if (_obj == NULL) {
3061 fd->print_on(_st);
3062 _st->cr();
3063 } else {
3064 fd->print_on_for(_st, _obj);
3065 _st->cr();
3066 }
3067 }
3070 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3071 Klass::oop_print_on(obj, st);
3073 if (this == SystemDictionary::String_klass()) {
3074 typeArrayOop value = java_lang_String::value(obj);
3075 juint offset = java_lang_String::offset(obj);
3076 juint length = java_lang_String::length(obj);
3077 if (value != NULL &&
3078 value->is_typeArray() &&
3079 offset <= (juint) value->length() &&
3080 offset + length <= (juint) value->length()) {
3081 st->print(BULLET"string: ");
3082 java_lang_String::print(obj, st);
3083 st->cr();
3084 if (!WizardMode) return; // that is enough
3085 }
3086 }
3088 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3089 FieldPrinter print_field(st, obj);
3090 do_nonstatic_fields(&print_field);
3092 if (this == SystemDictionary::Class_klass()) {
3093 st->print(BULLET"signature: ");
3094 java_lang_Class::print_signature(obj, st);
3095 st->cr();
3096 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3097 st->print(BULLET"fake entry for mirror: ");
3098 mirrored_klass->print_value_on_maybe_null(st);
3099 st->cr();
3100 Klass* array_klass = java_lang_Class::array_klass(obj);
3101 st->print(BULLET"fake entry for array: ");
3102 array_klass->print_value_on_maybe_null(st);
3103 st->cr();
3104 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3105 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3106 Klass* real_klass = java_lang_Class::as_Klass(obj);
3107 if (real_klass != NULL && real_klass->oop_is_instance()) {
3108 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3109 }
3110 } else if (this == SystemDictionary::MethodType_klass()) {
3111 st->print(BULLET"signature: ");
3112 java_lang_invoke_MethodType::print_signature(obj, st);
3113 st->cr();
3114 }
3115 }
3117 #endif //PRODUCT
3119 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3120 st->print("a ");
3121 name()->print_value_on(st);
3122 obj->print_address_on(st);
3123 if (this == SystemDictionary::String_klass()
3124 && java_lang_String::value(obj) != NULL) {
3125 ResourceMark rm;
3126 int len = java_lang_String::length(obj);
3127 int plen = (len < 24 ? len : 12);
3128 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3129 st->print(" = \"%s\"", str);
3130 if (len > plen)
3131 st->print("...[%d]", len);
3132 } else if (this == SystemDictionary::Class_klass()) {
3133 Klass* k = java_lang_Class::as_Klass(obj);
3134 st->print(" = ");
3135 if (k != NULL) {
3136 k->print_value_on(st);
3137 } else {
3138 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3139 st->print("%s", tname ? tname : "type?");
3140 }
3141 } else if (this == SystemDictionary::MethodType_klass()) {
3142 st->print(" = ");
3143 java_lang_invoke_MethodType::print_signature(obj, st);
3144 } else if (java_lang_boxing_object::is_instance(obj)) {
3145 st->print(" = ");
3146 java_lang_boxing_object::print(obj, st);
3147 } else if (this == SystemDictionary::LambdaForm_klass()) {
3148 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3149 if (vmentry != NULL) {
3150 st->print(" => ");
3151 vmentry->print_value_on(st);
3152 }
3153 } else if (this == SystemDictionary::MemberName_klass()) {
3154 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3155 if (vmtarget != NULL) {
3156 st->print(" = ");
3157 vmtarget->print_value_on(st);
3158 } else {
3159 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3160 st->print(".");
3161 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3162 }
3163 }
3164 }
3166 const char* InstanceKlass::internal_name() const {
3167 return external_name();
3168 }
3170 #if INCLUDE_SERVICES
3171 // Size Statistics
3172 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3173 Klass::collect_statistics(sz);
3175 sz->_inst_size = HeapWordSize * size_helper();
3176 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
3177 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
3178 sz->_nonstatic_oopmap_bytes = HeapWordSize *
3179 ((is_interface() || is_anonymous()) ?
3180 align_object_offset(nonstatic_oop_map_size()) :
3181 nonstatic_oop_map_size());
3183 int n = 0;
3184 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3185 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3186 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3187 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3188 n += (sz->_fields_bytes = sz->count_array(fields()));
3189 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3190 sz->_ro_bytes += n;
3192 const ConstantPool* cp = constants();
3193 if (cp) {
3194 cp->collect_statistics(sz);
3195 }
3197 const Annotations* anno = annotations();
3198 if (anno) {
3199 anno->collect_statistics(sz);
3200 }
3202 const Array<Method*>* methods_array = methods();
3203 if (methods()) {
3204 for (int i = 0; i < methods_array->length(); i++) {
3205 Method* method = methods_array->at(i);
3206 if (method) {
3207 sz->_method_count ++;
3208 method->collect_statistics(sz);
3209 }
3210 }
3211 }
3212 }
3213 #endif // INCLUDE_SERVICES
3215 // Verification
3217 class VerifyFieldClosure: public OopClosure {
3218 protected:
3219 template <class T> void do_oop_work(T* p) {
3220 oop obj = oopDesc::load_decode_heap_oop(p);
3221 if (!obj->is_oop_or_null()) {
3222 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
3223 Universe::print();
3224 guarantee(false, "boom");
3225 }
3226 }
3227 public:
3228 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3229 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3230 };
3232 void InstanceKlass::verify_on(outputStream* st) {
3233 #ifndef PRODUCT
3234 // Avoid redundant verifies, this really should be in product.
3235 if (_verify_count == Universe::verify_count()) return;
3236 _verify_count = Universe::verify_count();
3237 #endif
3239 // Verify Klass
3240 Klass::verify_on(st);
3242 // Verify that klass is present in ClassLoaderData
3243 guarantee(class_loader_data()->contains_klass(this),
3244 "this class isn't found in class loader data");
3246 // Verify vtables
3247 if (is_linked()) {
3248 ResourceMark rm;
3249 // $$$ This used to be done only for m/s collections. Doing it
3250 // always seemed a valid generalization. (DLD -- 6/00)
3251 vtable()->verify(st);
3252 }
3254 // Verify first subklass
3255 if (subklass_oop() != NULL) {
3256 guarantee(subklass_oop()->is_klass(), "should be klass");
3257 }
3259 // Verify siblings
3260 Klass* super = this->super();
3261 Klass* sib = next_sibling();
3262 if (sib != NULL) {
3263 if (sib == this) {
3264 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3265 }
3267 guarantee(sib->is_klass(), "should be klass");
3268 guarantee(sib->super() == super, "siblings should have same superklass");
3269 }
3271 // Verify implementor fields
3272 Klass* im = implementor();
3273 if (im != NULL) {
3274 guarantee(is_interface(), "only interfaces should have implementor set");
3275 guarantee(im->is_klass(), "should be klass");
3276 guarantee(!im->is_interface() || im == this,
3277 "implementors cannot be interfaces");
3278 }
3280 // Verify local interfaces
3281 if (local_interfaces()) {
3282 Array<Klass*>* local_interfaces = this->local_interfaces();
3283 for (int j = 0; j < local_interfaces->length(); j++) {
3284 Klass* e = local_interfaces->at(j);
3285 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3286 }
3287 }
3289 // Verify transitive interfaces
3290 if (transitive_interfaces() != NULL) {
3291 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3292 for (int j = 0; j < transitive_interfaces->length(); j++) {
3293 Klass* e = transitive_interfaces->at(j);
3294 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3295 }
3296 }
3298 // Verify methods
3299 if (methods() != NULL) {
3300 Array<Method*>* methods = this->methods();
3301 for (int j = 0; j < methods->length(); j++) {
3302 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3303 }
3304 for (int j = 0; j < methods->length() - 1; j++) {
3305 Method* m1 = methods->at(j);
3306 Method* m2 = methods->at(j + 1);
3307 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3308 }
3309 }
3311 // Verify method ordering
3312 if (method_ordering() != NULL) {
3313 Array<int>* method_ordering = this->method_ordering();
3314 int length = method_ordering->length();
3315 if (JvmtiExport::can_maintain_original_method_order() ||
3316 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3317 guarantee(length == methods()->length(), "invalid method ordering length");
3318 jlong sum = 0;
3319 for (int j = 0; j < length; j++) {
3320 int original_index = method_ordering->at(j);
3321 guarantee(original_index >= 0, "invalid method ordering index");
3322 guarantee(original_index < length, "invalid method ordering index");
3323 sum += original_index;
3324 }
3325 // Verify sum of indices 0,1,...,length-1
3326 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3327 } else {
3328 guarantee(length == 0, "invalid method ordering length");
3329 }
3330 }
3332 // Verify default methods
3333 if (default_methods() != NULL) {
3334 Array<Method*>* methods = this->default_methods();
3335 for (int j = 0; j < methods->length(); j++) {
3336 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3337 }
3338 for (int j = 0; j < methods->length() - 1; j++) {
3339 Method* m1 = methods->at(j);
3340 Method* m2 = methods->at(j + 1);
3341 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3342 }
3343 }
3345 // Verify JNI static field identifiers
3346 if (jni_ids() != NULL) {
3347 jni_ids()->verify(this);
3348 }
3350 // Verify other fields
3351 if (array_klasses() != NULL) {
3352 guarantee(array_klasses()->is_klass(), "should be klass");
3353 }
3354 if (constants() != NULL) {
3355 guarantee(constants()->is_constantPool(), "should be constant pool");
3356 }
3357 const Klass* host = host_klass();
3358 if (host != NULL) {
3359 guarantee(host->is_klass(), "should be klass");
3360 }
3361 }
3363 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3364 Klass::oop_verify_on(obj, st);
3365 VerifyFieldClosure blk;
3366 obj->oop_iterate_no_header(&blk);
3367 }
3370 // JNIid class for jfieldIDs only
3371 // Note to reviewers:
3372 // These JNI functions are just moved over to column 1 and not changed
3373 // in the compressed oops workspace.
3374 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3375 _holder = holder;
3376 _offset = offset;
3377 _next = next;
3378 debug_only(_is_static_field_id = false;)
3379 }
3382 JNIid* JNIid::find(int offset) {
3383 JNIid* current = this;
3384 while (current != NULL) {
3385 if (current->offset() == offset) return current;
3386 current = current->next();
3387 }
3388 return NULL;
3389 }
3391 void JNIid::deallocate(JNIid* current) {
3392 while (current != NULL) {
3393 JNIid* next = current->next();
3394 delete current;
3395 current = next;
3396 }
3397 }
3400 void JNIid::verify(Klass* holder) {
3401 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3402 int end_field_offset;
3403 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3405 JNIid* current = this;
3406 while (current != NULL) {
3407 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3408 #ifdef ASSERT
3409 int o = current->offset();
3410 if (current->is_static_field_id()) {
3411 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3412 }
3413 #endif
3414 current = current->next();
3415 }
3416 }
3419 #ifdef ASSERT
3420 void InstanceKlass::set_init_state(ClassState state) {
3421 bool good_state = is_shared() ? (_init_state <= state)
3422 : (_init_state < state);
3423 assert(good_state || state == allocated, "illegal state transition");
3424 _init_state = (u1)state;
3425 }
3426 #endif
3429 // RedefineClasses() support for previous versions:
3431 // Purge previous versions
3432 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3433 if (ik->previous_versions() != NULL) {
3434 // This klass has previous versions so see what we can cleanup
3435 // while it is safe to do so.
3437 int deleted_count = 0; // leave debugging breadcrumbs
3438 int live_count = 0;
3439 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3440 ClassLoaderData::the_null_class_loader_data() :
3441 ik->class_loader_data();
3443 // RC_TRACE macro has an embedded ResourceMark
3444 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3445 ik->external_name(), ik->previous_versions()->length()));
3447 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3448 // check the previous versions array
3449 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3450 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3451 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3453 ConstantPool* pvcp = cp_ref;
3454 if (!pvcp->on_stack()) {
3455 // If the constant pool isn't on stack, none of the methods
3456 // are executing. Delete all the methods, the constant pool and
3457 // and this previous version node.
3458 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3459 if (method_refs != NULL) {
3460 for (int j = method_refs->length() - 1; j >= 0; j--) {
3461 Method* method = method_refs->at(j);
3462 assert(method != NULL, "method ref was unexpectedly cleared");
3463 method_refs->remove_at(j);
3464 // method will be freed with associated class.
3465 }
3466 }
3467 // Remove the constant pool
3468 delete pv_node;
3469 // Since we are traversing the array backwards, we don't have to
3470 // do anything special with the index.
3471 ik->previous_versions()->remove_at(i);
3472 deleted_count++;
3473 continue;
3474 } else {
3475 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3476 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3477 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3478 live_count++;
3479 }
3481 // At least one method is live in this previous version, clean out
3482 // the others or mark them as obsolete.
3483 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3484 if (method_refs != NULL) {
3485 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3486 method_refs->length()));
3487 for (int j = method_refs->length() - 1; j >= 0; j--) {
3488 Method* method = method_refs->at(j);
3489 assert(method != NULL, "method ref was unexpectedly cleared");
3491 // Remove the emcp method if it's not executing
3492 // If it's been made obsolete by a redefinition of a non-emcp
3493 // method, mark it as obsolete but leave it to clean up later.
3494 if (!method->on_stack()) {
3495 method_refs->remove_at(j);
3496 } else if (emcp_method_count == 0) {
3497 method->set_is_obsolete();
3498 } else {
3499 // RC_TRACE macro has an embedded ResourceMark
3500 RC_TRACE(0x00000200,
3501 ("purge: %s(%s): prev method @%d in version @%d is alive",
3502 method->name()->as_C_string(),
3503 method->signature()->as_C_string(), j, i));
3504 }
3505 }
3506 }
3507 }
3508 assert(ik->previous_versions()->length() == live_count, "sanity check");
3509 RC_TRACE(0x00000200,
3510 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3511 deleted_count));
3512 }
3513 }
3515 // External interface for use during class unloading.
3516 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3517 // Call with >0 emcp methods since they are not currently being redefined.
3518 purge_previous_versions_internal(ik, 1);
3519 }
3522 // Potentially add an information node that contains pointers to the
3523 // interesting parts of the previous version of the_class.
3524 // This is also where we clean out any unused references.
3525 // Note that while we delete nodes from the _previous_versions
3526 // array, we never delete the array itself until the klass is
3527 // unloaded. The has_been_redefined() query depends on that fact.
3528 //
3529 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3530 BitMap* emcp_methods, int emcp_method_count) {
3531 assert(Thread::current()->is_VM_thread(),
3532 "only VMThread can add previous versions");
3534 if (_previous_versions == NULL) {
3535 // This is the first previous version so make some space.
3536 // Start with 2 elements under the assumption that the class
3537 // won't be redefined much.
3538 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3539 GrowableArray<PreviousVersionNode *>(2, true);
3540 }
3542 ConstantPool* cp_ref = ikh->constants();
3544 // RC_TRACE macro has an embedded ResourceMark
3545 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3546 "on_stack=%d",
3547 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3548 cp_ref->on_stack()));
3550 // If the constant pool for this previous version of the class
3551 // is not marked as being on the stack, then none of the methods
3552 // in this previous version of the class are on the stack so
3553 // we don't need to create a new PreviousVersionNode. However,
3554 // we still need to examine older previous versions below.
3555 Array<Method*>* old_methods = ikh->methods();
3557 if (cp_ref->on_stack()) {
3558 PreviousVersionNode * pv_node = NULL;
3559 if (emcp_method_count == 0) {
3560 // non-shared ConstantPool gets a reference
3561 pv_node = new PreviousVersionNode(cp_ref, NULL);
3562 RC_TRACE(0x00000400,
3563 ("add: all methods are obsolete; flushing any EMCP refs"));
3564 } else {
3565 int local_count = 0;
3566 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3567 GrowableArray<Method*>(emcp_method_count, true);
3568 for (int i = 0; i < old_methods->length(); i++) {
3569 if (emcp_methods->at(i)) {
3570 // this old method is EMCP. Save it only if it's on the stack
3571 Method* old_method = old_methods->at(i);
3572 if (old_method->on_stack()) {
3573 method_refs->append(old_method);
3574 }
3575 if (++local_count >= emcp_method_count) {
3576 // no more EMCP methods so bail out now
3577 break;
3578 }
3579 }
3580 }
3581 // non-shared ConstantPool gets a reference
3582 pv_node = new PreviousVersionNode(cp_ref, method_refs);
3583 }
3584 // append new previous version.
3585 _previous_versions->append(pv_node);
3586 }
3588 // Since the caller is the VMThread and we are at a safepoint, this
3589 // is a good time to clear out unused references.
3591 RC_TRACE(0x00000400, ("add: previous version length=%d",
3592 _previous_versions->length()));
3594 // Purge previous versions not executing on the stack
3595 purge_previous_versions_internal(this, emcp_method_count);
3597 int obsolete_method_count = old_methods->length() - emcp_method_count;
3599 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3600 _previous_versions->length() > 0) {
3601 // We have a mix of obsolete and EMCP methods so we have to
3602 // clear out any matching EMCP method entries the hard way.
3603 int local_count = 0;
3604 for (int i = 0; i < old_methods->length(); i++) {
3605 if (!emcp_methods->at(i)) {
3606 // only obsolete methods are interesting
3607 Method* old_method = old_methods->at(i);
3608 Symbol* m_name = old_method->name();
3609 Symbol* m_signature = old_method->signature();
3611 // we might not have added the last entry
3612 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3613 // check the previous versions array for non executing obsolete methods
3614 PreviousVersionNode * pv_node = _previous_versions->at(j);
3616 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3617 if (method_refs == NULL) {
3618 // We have run into a PreviousVersion generation where
3619 // all methods were made obsolete during that generation's
3620 // RedefineClasses() operation. At the time of that
3621 // operation, all EMCP methods were flushed so we don't
3622 // have to go back any further.
3623 //
3624 // A NULL method_refs is different than an empty method_refs.
3625 // We cannot infer any optimizations about older generations
3626 // from an empty method_refs for the current generation.
3627 break;
3628 }
3630 for (int k = method_refs->length() - 1; k >= 0; k--) {
3631 Method* method = method_refs->at(k);
3633 if (!method->is_obsolete() &&
3634 method->name() == m_name &&
3635 method->signature() == m_signature) {
3636 // The current RedefineClasses() call has made all EMCP
3637 // versions of this method obsolete so mark it as obsolete
3638 // and remove the reference.
3639 RC_TRACE(0x00000400,
3640 ("add: %s(%s): flush obsolete method @%d in version @%d",
3641 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3643 method->set_is_obsolete();
3644 // Leave obsolete methods on the previous version list to
3645 // clean up later.
3646 break;
3647 }
3648 }
3650 // The previous loop may not find a matching EMCP method, but
3651 // that doesn't mean that we can optimize and not go any
3652 // further back in the PreviousVersion generations. The EMCP
3653 // method for this generation could have already been deleted,
3654 // but there still may be an older EMCP method that has not
3655 // been deleted.
3656 }
3658 if (++local_count >= obsolete_method_count) {
3659 // no more obsolete methods so bail out now
3660 break;
3661 }
3662 }
3663 }
3664 }
3665 } // end add_previous_version()
3668 // Determine if InstanceKlass has a previous version.
3669 bool InstanceKlass::has_previous_version() const {
3670 return (_previous_versions != NULL && _previous_versions->length() > 0);
3671 } // end has_previous_version()
3674 Method* InstanceKlass::method_with_idnum(int idnum) {
3675 Method* m = NULL;
3676 if (idnum < methods()->length()) {
3677 m = methods()->at(idnum);
3678 }
3679 if (m == NULL || m->method_idnum() != idnum) {
3680 for (int index = 0; index < methods()->length(); ++index) {
3681 m = methods()->at(index);
3682 if (m->method_idnum() == idnum) {
3683 return m;
3684 }
3685 }
3686 // None found, return null for the caller to handle.
3687 return NULL;
3688 }
3689 return m;
3690 }
3692 jint InstanceKlass::get_cached_class_file_len() {
3693 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3694 }
3696 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3697 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3698 }
3701 // Construct a PreviousVersionNode entry for the array hung off
3702 // the InstanceKlass.
3703 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3704 GrowableArray<Method*>* prev_EMCP_methods) {
3706 _prev_constant_pool = prev_constant_pool;
3707 _prev_EMCP_methods = prev_EMCP_methods;
3708 }
3711 // Destroy a PreviousVersionNode
3712 PreviousVersionNode::~PreviousVersionNode() {
3713 if (_prev_constant_pool != NULL) {
3714 _prev_constant_pool = NULL;
3715 }
3717 if (_prev_EMCP_methods != NULL) {
3718 delete _prev_EMCP_methods;
3719 }
3720 }
3722 // Construct a helper for walking the previous versions array
3723 PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) {
3724 _thread = thread;
3725 _previous_versions = ik->previous_versions();
3726 _current_index = 0;
3727 _current_p = NULL;
3728 _current_constant_pool_handle = constantPoolHandle(thread, ik->constants());
3729 }
3732 // Return the interesting information for the next previous version
3733 // of the klass. Returns NULL if there are no more previous versions.
3734 PreviousVersionNode* PreviousVersionWalker::next_previous_version() {
3735 if (_previous_versions == NULL) {
3736 // no previous versions so nothing to return
3737 return NULL;
3738 }
3740 _current_p = NULL; // reset to NULL
3741 _current_constant_pool_handle = NULL;
3743 int length = _previous_versions->length();
3745 while (_current_index < length) {
3746 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3748 // Save a handle to the constant pool for this previous version,
3749 // which keeps all the methods from being deallocated.
3750 _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool());
3751 _current_p = pv_node;
3752 return pv_node;
3753 }
3755 return NULL;
3756 } // end next_previous_version()