Mon, 14 Apr 2014 14:27:45 -0400
8033150: invokestatic: IncompatibleClassChangeError trying to invoke static method from a parent in presence of conflicting defaults.
Summary: A static method should be preferred during method resolution over an overpass, search the current class as well as its superclasses.
Reviewed-by: acorn, coleenp, kamg
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/metadataFactory.hpp"
39 #include "memory/oopFactory.hpp"
40 #include "oops/fieldStreams.hpp"
41 #include "oops/instanceClassLoaderKlass.hpp"
42 #include "oops/instanceKlass.hpp"
43 #include "oops/instanceMirrorKlass.hpp"
44 #include "oops/instanceOop.hpp"
45 #include "oops/klass.inline.hpp"
46 #include "oops/method.hpp"
47 #include "oops/oop.inline.hpp"
48 #include "oops/symbol.hpp"
49 #include "prims/jvmtiExport.hpp"
50 #include "prims/jvmtiRedefineClassesTrace.hpp"
51 #include "prims/jvmtiRedefineClasses.hpp"
52 #include "prims/methodComparator.hpp"
53 #include "runtime/fieldDescriptor.hpp"
54 #include "runtime/handles.inline.hpp"
55 #include "runtime/javaCalls.hpp"
56 #include "runtime/mutexLocker.hpp"
57 #include "runtime/thread.inline.hpp"
58 #include "services/classLoadingService.hpp"
59 #include "services/threadService.hpp"
60 #include "utilities/dtrace.hpp"
61 #include "utilities/macros.hpp"
62 #if INCLUDE_ALL_GCS
63 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
64 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
65 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
66 #include "gc_implementation/g1/g1RemSet.inline.hpp"
67 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
68 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
69 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
70 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
71 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
72 #include "oops/oop.pcgc.inline.hpp"
73 #endif // INCLUDE_ALL_GCS
74 #ifdef COMPILER1
75 #include "c1/c1_Compiler.hpp"
76 #endif
78 #ifdef DTRACE_ENABLED
80 #ifndef USDT2
82 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
83 char*, intptr_t, oop, intptr_t);
84 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
85 char*, intptr_t, oop, intptr_t, int);
86 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
87 char*, intptr_t, oop, intptr_t, int);
88 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
89 char*, intptr_t, oop, intptr_t, int);
90 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
91 char*, intptr_t, oop, intptr_t, int);
92 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
93 char*, intptr_t, oop, intptr_t, int);
94 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
95 char*, intptr_t, oop, intptr_t, int);
96 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
97 char*, intptr_t, oop, intptr_t, int);
99 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
100 { \
101 char* data = NULL; \
102 int len = 0; \
103 Symbol* name = (clss)->name(); \
104 if (name != NULL) { \
105 data = (char*)name->bytes(); \
106 len = name->utf8_length(); \
107 } \
108 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \
109 data, len, SOLARIS_ONLY((void *))(clss)->class_loader(), thread_type); \
110 }
112 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
113 { \
114 char* data = NULL; \
115 int len = 0; \
116 Symbol* name = (clss)->name(); \
117 if (name != NULL) { \
118 data = (char*)name->bytes(); \
119 len = name->utf8_length(); \
120 } \
121 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \
122 data, len, SOLARIS_ONLY((void *))(clss)->class_loader(), thread_type, wait); \
123 }
124 #else /* USDT2 */
126 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
127 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
128 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
129 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
130 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
131 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
132 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
133 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
134 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
135 { \
136 char* data = NULL; \
137 int len = 0; \
138 Symbol* name = (clss)->name(); \
139 if (name != NULL) { \
140 data = (char*)name->bytes(); \
141 len = name->utf8_length(); \
142 } \
143 HOTSPOT_CLASS_INITIALIZATION_##type( \
144 data, len, (clss)->class_loader(), thread_type); \
145 }
147 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
148 { \
149 char* data = NULL; \
150 int len = 0; \
151 Symbol* name = (clss)->name(); \
152 if (name != NULL) { \
153 data = (char*)name->bytes(); \
154 len = name->utf8_length(); \
155 } \
156 HOTSPOT_CLASS_INITIALIZATION_##type( \
157 data, len, (clss)->class_loader(), thread_type, wait); \
158 }
159 #endif /* USDT2 */
161 #else // ndef DTRACE_ENABLED
163 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
164 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
166 #endif // ndef DTRACE_ENABLED
168 volatile int InstanceKlass::_total_instanceKlass_count = 0;
170 InstanceKlass* InstanceKlass::allocate_instance_klass(
171 ClassLoaderData* loader_data,
172 int vtable_len,
173 int itable_len,
174 int static_field_size,
175 int nonstatic_oop_map_size,
176 ReferenceType rt,
177 AccessFlags access_flags,
178 Symbol* name,
179 Klass* super_klass,
180 bool is_anonymous,
181 TRAPS) {
183 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
184 access_flags.is_interface(), is_anonymous);
186 // Allocation
187 InstanceKlass* ik;
188 if (rt == REF_NONE) {
189 if (name == vmSymbols::java_lang_Class()) {
190 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
191 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
192 access_flags, is_anonymous);
193 } else if (name == vmSymbols::java_lang_ClassLoader() ||
194 (SystemDictionary::ClassLoader_klass_loaded() &&
195 super_klass != NULL &&
196 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
197 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
198 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
199 access_flags, is_anonymous);
200 } else {
201 // normal class
202 ik = new (loader_data, size, THREAD) InstanceKlass(
203 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
204 access_flags, is_anonymous);
205 }
206 } else {
207 // reference klass
208 ik = new (loader_data, size, THREAD) InstanceRefKlass(
209 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
210 access_flags, is_anonymous);
211 }
213 // Check for pending exception before adding to the loader data and incrementing
214 // class count. Can get OOM here.
215 if (HAS_PENDING_EXCEPTION) {
216 return NULL;
217 }
219 // Add all classes to our internal class loader list here,
220 // including classes in the bootstrap (NULL) class loader.
221 loader_data->add_class(ik);
223 Atomic::inc(&_total_instanceKlass_count);
224 return ik;
225 }
228 // copy method ordering from resource area to Metaspace
229 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
230 if (m != NULL) {
231 // allocate a new array and copy contents (memcpy?)
232 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
233 for (int i = 0; i < m->length(); i++) {
234 _method_ordering->at_put(i, m->at(i));
235 }
236 } else {
237 _method_ordering = Universe::the_empty_int_array();
238 }
239 }
241 // create a new array of vtable_indices for default methods
242 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
243 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
244 assert(default_vtable_indices() == NULL, "only create once");
245 set_default_vtable_indices(vtable_indices);
246 return vtable_indices;
247 }
249 InstanceKlass::InstanceKlass(int vtable_len,
250 int itable_len,
251 int static_field_size,
252 int nonstatic_oop_map_size,
253 ReferenceType rt,
254 AccessFlags access_flags,
255 bool is_anonymous) {
256 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
258 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
259 access_flags.is_interface(), is_anonymous);
261 set_vtable_length(vtable_len);
262 set_itable_length(itable_len);
263 set_static_field_size(static_field_size);
264 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
265 set_access_flags(access_flags);
266 _misc_flags = 0; // initialize to zero
267 set_is_anonymous(is_anonymous);
268 assert(size() == iksize, "wrong size for object");
270 set_array_klasses(NULL);
271 set_methods(NULL);
272 set_method_ordering(NULL);
273 set_default_methods(NULL);
274 set_default_vtable_indices(NULL);
275 set_local_interfaces(NULL);
276 set_transitive_interfaces(NULL);
277 init_implementor();
278 set_fields(NULL, 0);
279 set_constants(NULL);
280 set_class_loader_data(NULL);
281 set_source_file_name_index(0);
282 set_source_debug_extension(NULL, 0);
283 set_array_name(NULL);
284 set_inner_classes(NULL);
285 set_static_oop_field_count(0);
286 set_nonstatic_field_size(0);
287 set_is_marked_dependent(false);
288 set_init_state(InstanceKlass::allocated);
289 set_init_thread(NULL);
290 set_reference_type(rt);
291 set_oop_map_cache(NULL);
292 set_jni_ids(NULL);
293 set_osr_nmethods_head(NULL);
294 set_breakpoints(NULL);
295 init_previous_versions();
296 set_generic_signature_index(0);
297 release_set_methods_jmethod_ids(NULL);
298 set_annotations(NULL);
299 set_jvmti_cached_class_field_map(NULL);
300 set_initial_method_idnum(0);
301 _dependencies = NULL;
302 set_jvmti_cached_class_field_map(NULL);
303 set_cached_class_file(NULL);
304 set_initial_method_idnum(0);
305 set_minor_version(0);
306 set_major_version(0);
307 NOT_PRODUCT(_verify_count = 0;)
309 // initialize the non-header words to zero
310 intptr_t* p = (intptr_t*)this;
311 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
312 p[index] = NULL_WORD;
313 }
315 // Set temporary value until parseClassFile updates it with the real instance
316 // size.
317 set_layout_helper(Klass::instance_layout_helper(0, true));
318 }
321 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
322 Array<Method*>* methods) {
323 if (methods != NULL && methods != Universe::the_empty_method_array() &&
324 !methods->is_shared()) {
325 for (int i = 0; i < methods->length(); i++) {
326 Method* method = methods->at(i);
327 if (method == NULL) continue; // maybe null if error processing
328 // Only want to delete methods that are not executing for RedefineClasses.
329 // The previous version will point to them so they're not totally dangling
330 assert (!method->on_stack(), "shouldn't be called with methods on stack");
331 MetadataFactory::free_metadata(loader_data, method);
332 }
333 MetadataFactory::free_array<Method*>(loader_data, methods);
334 }
335 }
337 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
338 Klass* super_klass,
339 Array<Klass*>* local_interfaces,
340 Array<Klass*>* transitive_interfaces) {
341 // Only deallocate transitive interfaces if not empty, same as super class
342 // or same as local interfaces. See code in parseClassFile.
343 Array<Klass*>* ti = transitive_interfaces;
344 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
345 // check that the interfaces don't come from super class
346 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
347 InstanceKlass::cast(super_klass)->transitive_interfaces();
348 if (ti != sti && ti != NULL && !ti->is_shared()) {
349 MetadataFactory::free_array<Klass*>(loader_data, ti);
350 }
351 }
353 // local interfaces can be empty
354 if (local_interfaces != Universe::the_empty_klass_array() &&
355 local_interfaces != NULL && !local_interfaces->is_shared()) {
356 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
357 }
358 }
360 // This function deallocates the metadata and C heap pointers that the
361 // InstanceKlass points to.
362 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
364 // Orphan the mirror first, CMS thinks it's still live.
365 if (java_mirror() != NULL) {
366 java_lang_Class::set_klass(java_mirror(), NULL);
367 }
369 // Need to take this class off the class loader data list.
370 loader_data->remove_class(this);
372 // The array_klass for this class is created later, after error handling.
373 // For class redefinition, we keep the original class so this scratch class
374 // doesn't have an array class. Either way, assert that there is nothing
375 // to deallocate.
376 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
378 // Release C heap allocated data that this might point to, which includes
379 // reference counting symbol names.
380 release_C_heap_structures();
382 deallocate_methods(loader_data, methods());
383 set_methods(NULL);
385 if (method_ordering() != NULL &&
386 method_ordering() != Universe::the_empty_int_array() &&
387 !method_ordering()->is_shared()) {
388 MetadataFactory::free_array<int>(loader_data, method_ordering());
389 }
390 set_method_ordering(NULL);
392 // default methods can be empty
393 if (default_methods() != NULL &&
394 default_methods() != Universe::the_empty_method_array() &&
395 !default_methods()->is_shared()) {
396 MetadataFactory::free_array<Method*>(loader_data, default_methods());
397 }
398 // Do NOT deallocate the default methods, they are owned by superinterfaces.
399 set_default_methods(NULL);
401 // default methods vtable indices can be empty
402 if (default_vtable_indices() != NULL &&
403 !default_vtable_indices()->is_shared()) {
404 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
405 }
406 set_default_vtable_indices(NULL);
409 // This array is in Klass, but remove it with the InstanceKlass since
410 // this place would be the only caller and it can share memory with transitive
411 // interfaces.
412 if (secondary_supers() != NULL &&
413 secondary_supers() != Universe::the_empty_klass_array() &&
414 secondary_supers() != transitive_interfaces() &&
415 !secondary_supers()->is_shared()) {
416 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
417 }
418 set_secondary_supers(NULL);
420 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
421 set_transitive_interfaces(NULL);
422 set_local_interfaces(NULL);
424 if (fields() != NULL && !fields()->is_shared()) {
425 MetadataFactory::free_array<jushort>(loader_data, fields());
426 }
427 set_fields(NULL, 0);
429 // If a method from a redefined class is using this constant pool, don't
430 // delete it, yet. The new class's previous version will point to this.
431 if (constants() != NULL) {
432 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
433 if (!constants()->is_shared()) {
434 MetadataFactory::free_metadata(loader_data, constants());
435 }
436 set_constants(NULL);
437 }
439 if (inner_classes() != NULL &&
440 inner_classes() != Universe::the_empty_short_array() &&
441 !inner_classes()->is_shared()) {
442 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
443 }
444 set_inner_classes(NULL);
446 // We should deallocate the Annotations instance if it's not in shared spaces.
447 if (annotations() != NULL && !annotations()->is_shared()) {
448 MetadataFactory::free_metadata(loader_data, annotations());
449 }
450 set_annotations(NULL);
451 }
453 bool InstanceKlass::should_be_initialized() const {
454 return !is_initialized();
455 }
457 klassVtable* InstanceKlass::vtable() const {
458 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
459 }
461 klassItable* InstanceKlass::itable() const {
462 return new klassItable(instanceKlassHandle(this));
463 }
465 void InstanceKlass::eager_initialize(Thread *thread) {
466 if (!EagerInitialization) return;
468 if (this->is_not_initialized()) {
469 // abort if the the class has a class initializer
470 if (this->class_initializer() != NULL) return;
472 // abort if it is java.lang.Object (initialization is handled in genesis)
473 Klass* super = this->super();
474 if (super == NULL) return;
476 // abort if the super class should be initialized
477 if (!InstanceKlass::cast(super)->is_initialized()) return;
479 // call body to expose the this pointer
480 instanceKlassHandle this_oop(thread, this);
481 eager_initialize_impl(this_oop);
482 }
483 }
485 // JVMTI spec thinks there are signers and protection domain in the
486 // instanceKlass. These accessors pretend these fields are there.
487 // The hprof specification also thinks these fields are in InstanceKlass.
488 oop InstanceKlass::protection_domain() const {
489 // return the protection_domain from the mirror
490 return java_lang_Class::protection_domain(java_mirror());
491 }
493 // To remove these from requires an incompatible change and CCC request.
494 objArrayOop InstanceKlass::signers() const {
495 // return the signers from the mirror
496 return java_lang_Class::signers(java_mirror());
497 }
499 oop InstanceKlass::init_lock() const {
500 // return the init lock from the mirror
501 oop lock = java_lang_Class::init_lock(java_mirror());
502 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
503 "only fully initialized state can have a null lock");
504 return lock;
505 }
507 // Set the initialization lock to null so the object can be GC'ed. Any racing
508 // threads to get this lock will see a null lock and will not lock.
509 // That's okay because they all check for initialized state after getting
510 // the lock and return.
511 void InstanceKlass::fence_and_clear_init_lock() {
512 // make sure previous stores are all done, notably the init_state.
513 OrderAccess::storestore();
514 java_lang_Class::set_init_lock(java_mirror(), NULL);
515 assert(!is_not_initialized(), "class must be initialized now");
516 }
518 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
519 EXCEPTION_MARK;
520 oop init_lock = this_oop->init_lock();
521 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
523 // abort if someone beat us to the initialization
524 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
526 ClassState old_state = this_oop->init_state();
527 link_class_impl(this_oop, true, THREAD);
528 if (HAS_PENDING_EXCEPTION) {
529 CLEAR_PENDING_EXCEPTION;
530 // Abort if linking the class throws an exception.
532 // Use a test to avoid redundantly resetting the state if there's
533 // no change. Set_init_state() asserts that state changes make
534 // progress, whereas here we might just be spinning in place.
535 if( old_state != this_oop->_init_state )
536 this_oop->set_init_state (old_state);
537 } else {
538 // linking successfull, mark class as initialized
539 this_oop->set_init_state (fully_initialized);
540 this_oop->fence_and_clear_init_lock();
541 // trace
542 if (TraceClassInitialization) {
543 ResourceMark rm(THREAD);
544 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
545 }
546 }
547 }
550 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
551 // process. The step comments refers to the procedure described in that section.
552 // Note: implementation moved to static method to expose the this pointer.
553 void InstanceKlass::initialize(TRAPS) {
554 if (this->should_be_initialized()) {
555 HandleMark hm(THREAD);
556 instanceKlassHandle this_oop(THREAD, this);
557 initialize_impl(this_oop, CHECK);
558 // Note: at this point the class may be initialized
559 // OR it may be in the state of being initialized
560 // in case of recursive initialization!
561 } else {
562 assert(is_initialized(), "sanity check");
563 }
564 }
567 bool InstanceKlass::verify_code(
568 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
569 // 1) Verify the bytecodes
570 Verifier::Mode mode =
571 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
572 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
573 }
576 // Used exclusively by the shared spaces dump mechanism to prevent
577 // classes mapped into the shared regions in new VMs from appearing linked.
579 void InstanceKlass::unlink_class() {
580 assert(is_linked(), "must be linked");
581 _init_state = loaded;
582 }
584 void InstanceKlass::link_class(TRAPS) {
585 assert(is_loaded(), "must be loaded");
586 if (!is_linked()) {
587 HandleMark hm(THREAD);
588 instanceKlassHandle this_oop(THREAD, this);
589 link_class_impl(this_oop, true, CHECK);
590 }
591 }
593 // Called to verify that a class can link during initialization, without
594 // throwing a VerifyError.
595 bool InstanceKlass::link_class_or_fail(TRAPS) {
596 assert(is_loaded(), "must be loaded");
597 if (!is_linked()) {
598 HandleMark hm(THREAD);
599 instanceKlassHandle this_oop(THREAD, this);
600 link_class_impl(this_oop, false, CHECK_false);
601 }
602 return is_linked();
603 }
605 bool InstanceKlass::link_class_impl(
606 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
607 // check for error state
608 if (this_oop->is_in_error_state()) {
609 ResourceMark rm(THREAD);
610 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
611 this_oop->external_name(), false);
612 }
613 // return if already verified
614 if (this_oop->is_linked()) {
615 return true;
616 }
618 // Timing
619 // timer handles recursion
620 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
621 JavaThread* jt = (JavaThread*)THREAD;
623 // link super class before linking this class
624 instanceKlassHandle super(THREAD, this_oop->super());
625 if (super.not_null()) {
626 if (super->is_interface()) { // check if super class is an interface
627 ResourceMark rm(THREAD);
628 Exceptions::fthrow(
629 THREAD_AND_LOCATION,
630 vmSymbols::java_lang_IncompatibleClassChangeError(),
631 "class %s has interface %s as super class",
632 this_oop->external_name(),
633 super->external_name()
634 );
635 return false;
636 }
638 link_class_impl(super, throw_verifyerror, CHECK_false);
639 }
641 // link all interfaces implemented by this class before linking this class
642 Array<Klass*>* interfaces = this_oop->local_interfaces();
643 int num_interfaces = interfaces->length();
644 for (int index = 0; index < num_interfaces; index++) {
645 HandleMark hm(THREAD);
646 instanceKlassHandle ih(THREAD, interfaces->at(index));
647 link_class_impl(ih, throw_verifyerror, CHECK_false);
648 }
650 // in case the class is linked in the process of linking its superclasses
651 if (this_oop->is_linked()) {
652 return true;
653 }
655 // trace only the link time for this klass that includes
656 // the verification time
657 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
658 ClassLoader::perf_class_link_selftime(),
659 ClassLoader::perf_classes_linked(),
660 jt->get_thread_stat()->perf_recursion_counts_addr(),
661 jt->get_thread_stat()->perf_timers_addr(),
662 PerfClassTraceTime::CLASS_LINK);
664 // verification & rewriting
665 {
666 oop init_lock = this_oop->init_lock();
667 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
668 // rewritten will have been set if loader constraint error found
669 // on an earlier link attempt
670 // don't verify or rewrite if already rewritten
672 if (!this_oop->is_linked()) {
673 if (!this_oop->is_rewritten()) {
674 {
675 // Timer includes any side effects of class verification (resolution,
676 // etc), but not recursive entry into verify_code().
677 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
678 ClassLoader::perf_class_verify_selftime(),
679 ClassLoader::perf_classes_verified(),
680 jt->get_thread_stat()->perf_recursion_counts_addr(),
681 jt->get_thread_stat()->perf_timers_addr(),
682 PerfClassTraceTime::CLASS_VERIFY);
683 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
684 if (!verify_ok) {
685 return false;
686 }
687 }
689 // Just in case a side-effect of verify linked this class already
690 // (which can sometimes happen since the verifier loads classes
691 // using custom class loaders, which are free to initialize things)
692 if (this_oop->is_linked()) {
693 return true;
694 }
696 // also sets rewritten
697 this_oop->rewrite_class(CHECK_false);
698 }
700 // relocate jsrs and link methods after they are all rewritten
701 this_oop->link_methods(CHECK_false);
703 // Initialize the vtable and interface table after
704 // methods have been rewritten since rewrite may
705 // fabricate new Method*s.
706 // also does loader constraint checking
707 if (!this_oop()->is_shared()) {
708 ResourceMark rm(THREAD);
709 this_oop->vtable()->initialize_vtable(true, CHECK_false);
710 this_oop->itable()->initialize_itable(true, CHECK_false);
711 }
712 #ifdef ASSERT
713 else {
714 ResourceMark rm(THREAD);
715 this_oop->vtable()->verify(tty, true);
716 // In case itable verification is ever added.
717 // this_oop->itable()->verify(tty, true);
718 }
719 #endif
720 this_oop->set_init_state(linked);
721 if (JvmtiExport::should_post_class_prepare()) {
722 Thread *thread = THREAD;
723 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
724 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
725 }
726 }
727 }
728 return true;
729 }
732 // Rewrite the byte codes of all of the methods of a class.
733 // The rewriter must be called exactly once. Rewriting must happen after
734 // verification but before the first method of the class is executed.
735 void InstanceKlass::rewrite_class(TRAPS) {
736 assert(is_loaded(), "must be loaded");
737 instanceKlassHandle this_oop(THREAD, this);
738 if (this_oop->is_rewritten()) {
739 assert(this_oop()->is_shared(), "rewriting an unshared class?");
740 return;
741 }
742 Rewriter::rewrite(this_oop, CHECK);
743 this_oop->set_rewritten();
744 }
746 // Now relocate and link method entry points after class is rewritten.
747 // This is outside is_rewritten flag. In case of an exception, it can be
748 // executed more than once.
749 void InstanceKlass::link_methods(TRAPS) {
750 int len = methods()->length();
751 for (int i = len-1; i >= 0; i--) {
752 methodHandle m(THREAD, methods()->at(i));
754 // Set up method entry points for compiler and interpreter .
755 m->link_method(m, CHECK);
757 // This is for JVMTI and unrelated to relocator but the last thing we do
758 #ifdef ASSERT
759 if (StressMethodComparator) {
760 ResourceMark rm(THREAD);
761 static int nmc = 0;
762 for (int j = i; j >= 0 && j >= i-4; j--) {
763 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
764 bool z = MethodComparator::methods_EMCP(m(),
765 methods()->at(j));
766 if (j == i && !z) {
767 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
768 assert(z, "method must compare equal to itself");
769 }
770 }
771 }
772 #endif //ASSERT
773 }
774 }
777 void InstanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
778 // Make sure klass is linked (verified) before initialization
779 // A class could already be verified, since it has been reflected upon.
780 this_oop->link_class(CHECK);
782 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_oop()), -1);
784 bool wait = false;
786 // refer to the JVM book page 47 for description of steps
787 // Step 1
788 {
789 oop init_lock = this_oop->init_lock();
790 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
792 Thread *self = THREAD; // it's passed the current thread
794 // Step 2
795 // If we were to use wait() instead of waitInterruptibly() then
796 // we might end up throwing IE from link/symbol resolution sites
797 // that aren't expected to throw. This would wreak havoc. See 6320309.
798 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
799 wait = true;
800 ol.waitUninterruptibly(CHECK);
801 }
803 // Step 3
804 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
805 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_oop()), -1,wait);
806 return;
807 }
809 // Step 4
810 if (this_oop->is_initialized()) {
811 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_oop()), -1,wait);
812 return;
813 }
815 // Step 5
816 if (this_oop->is_in_error_state()) {
817 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_oop()), -1,wait);
818 ResourceMark rm(THREAD);
819 const char* desc = "Could not initialize class ";
820 const char* className = this_oop->external_name();
821 size_t msglen = strlen(desc) + strlen(className) + 1;
822 char* message = NEW_RESOURCE_ARRAY(char, msglen);
823 if (NULL == message) {
824 // Out of memory: can't create detailed error message
825 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
826 } else {
827 jio_snprintf(message, msglen, "%s%s", desc, className);
828 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
829 }
830 }
832 // Step 6
833 this_oop->set_init_state(being_initialized);
834 this_oop->set_init_thread(self);
835 }
837 // Step 7
838 Klass* super_klass = this_oop->super();
839 if (super_klass != NULL && !this_oop->is_interface() && super_klass->should_be_initialized()) {
840 super_klass->initialize(THREAD);
842 if (HAS_PENDING_EXCEPTION) {
843 Handle e(THREAD, PENDING_EXCEPTION);
844 CLEAR_PENDING_EXCEPTION;
845 {
846 EXCEPTION_MARK;
847 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
848 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
849 }
850 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_oop()), -1,wait);
851 THROW_OOP(e());
852 }
853 }
855 if (this_oop->has_default_methods()) {
856 // Step 7.5: initialize any interfaces which have default methods
857 for (int i = 0; i < this_oop->local_interfaces()->length(); ++i) {
858 Klass* iface = this_oop->local_interfaces()->at(i);
859 InstanceKlass* ik = InstanceKlass::cast(iface);
860 if (ik->has_default_methods() && ik->should_be_initialized()) {
861 ik->initialize(THREAD);
863 if (HAS_PENDING_EXCEPTION) {
864 Handle e(THREAD, PENDING_EXCEPTION);
865 CLEAR_PENDING_EXCEPTION;
866 {
867 EXCEPTION_MARK;
868 // Locks object, set state, and notify all waiting threads
869 this_oop->set_initialization_state_and_notify(
870 initialization_error, THREAD);
872 // ignore any exception thrown, superclass initialization error is
873 // thrown below
874 CLEAR_PENDING_EXCEPTION;
875 }
876 DTRACE_CLASSINIT_PROBE_WAIT(
877 super__failed, InstanceKlass::cast(this_oop()), -1, wait);
878 THROW_OOP(e());
879 }
880 }
881 }
882 }
884 // Step 8
885 {
886 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
887 JavaThread* jt = (JavaThread*)THREAD;
888 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_oop()), -1,wait);
889 // Timer includes any side effects of class initialization (resolution,
890 // etc), but not recursive entry into call_class_initializer().
891 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
892 ClassLoader::perf_class_init_selftime(),
893 ClassLoader::perf_classes_inited(),
894 jt->get_thread_stat()->perf_recursion_counts_addr(),
895 jt->get_thread_stat()->perf_timers_addr(),
896 PerfClassTraceTime::CLASS_CLINIT);
897 this_oop->call_class_initializer(THREAD);
898 }
900 // Step 9
901 if (!HAS_PENDING_EXCEPTION) {
902 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
903 { ResourceMark rm(THREAD);
904 debug_only(this_oop->vtable()->verify(tty, true);)
905 }
906 }
907 else {
908 // Step 10 and 11
909 Handle e(THREAD, PENDING_EXCEPTION);
910 CLEAR_PENDING_EXCEPTION;
911 {
912 EXCEPTION_MARK;
913 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
914 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
915 }
916 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_oop()), -1,wait);
917 if (e->is_a(SystemDictionary::Error_klass())) {
918 THROW_OOP(e());
919 } else {
920 JavaCallArguments args(e);
921 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
922 vmSymbols::throwable_void_signature(),
923 &args);
924 }
925 }
926 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_oop()), -1,wait);
927 }
930 // Note: implementation moved to static method to expose the this pointer.
931 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
932 instanceKlassHandle kh(THREAD, this);
933 set_initialization_state_and_notify_impl(kh, state, CHECK);
934 }
936 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
937 oop init_lock = this_oop->init_lock();
938 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
939 this_oop->set_init_state(state);
940 this_oop->fence_and_clear_init_lock();
941 ol.notify_all(CHECK);
942 }
944 // The embedded _implementor field can only record one implementor.
945 // When there are more than one implementors, the _implementor field
946 // is set to the interface Klass* itself. Following are the possible
947 // values for the _implementor field:
948 // NULL - no implementor
949 // implementor Klass* - one implementor
950 // self - more than one implementor
951 //
952 // The _implementor field only exists for interfaces.
953 void InstanceKlass::add_implementor(Klass* k) {
954 assert(Compile_lock->owned_by_self(), "");
955 assert(is_interface(), "not interface");
956 // Filter out my subinterfaces.
957 // (Note: Interfaces are never on the subklass list.)
958 if (InstanceKlass::cast(k)->is_interface()) return;
960 // Filter out subclasses whose supers already implement me.
961 // (Note: CHA must walk subclasses of direct implementors
962 // in order to locate indirect implementors.)
963 Klass* sk = InstanceKlass::cast(k)->super();
964 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
965 // We only need to check one immediate superclass, since the
966 // implements_interface query looks at transitive_interfaces.
967 // Any supers of the super have the same (or fewer) transitive_interfaces.
968 return;
970 Klass* ik = implementor();
971 if (ik == NULL) {
972 set_implementor(k);
973 } else if (ik != this) {
974 // There is already an implementor. Use itself as an indicator of
975 // more than one implementors.
976 set_implementor(this);
977 }
979 // The implementor also implements the transitive_interfaces
980 for (int index = 0; index < local_interfaces()->length(); index++) {
981 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
982 }
983 }
985 void InstanceKlass::init_implementor() {
986 if (is_interface()) {
987 set_implementor(NULL);
988 }
989 }
992 void InstanceKlass::process_interfaces(Thread *thread) {
993 // link this class into the implementors list of every interface it implements
994 Klass* this_as_klass_oop = this;
995 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
996 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
997 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
998 assert(interf->is_interface(), "expected interface");
999 interf->add_implementor(this_as_klass_oop);
1000 }
1001 }
1003 bool InstanceKlass::can_be_primary_super_slow() const {
1004 if (is_interface())
1005 return false;
1006 else
1007 return Klass::can_be_primary_super_slow();
1008 }
1010 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1011 // The secondaries are the implemented interfaces.
1012 InstanceKlass* ik = InstanceKlass::cast(this);
1013 Array<Klass*>* interfaces = ik->transitive_interfaces();
1014 int num_secondaries = num_extra_slots + interfaces->length();
1015 if (num_secondaries == 0) {
1016 // Must share this for correct bootstrapping!
1017 set_secondary_supers(Universe::the_empty_klass_array());
1018 return NULL;
1019 } else if (num_extra_slots == 0) {
1020 // The secondary super list is exactly the same as the transitive interfaces.
1021 // Redefine classes has to be careful not to delete this!
1022 set_secondary_supers(interfaces);
1023 return NULL;
1024 } else {
1025 // Copy transitive interfaces to a temporary growable array to be constructed
1026 // into the secondary super list with extra slots.
1027 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1028 for (int i = 0; i < interfaces->length(); i++) {
1029 secondaries->push(interfaces->at(i));
1030 }
1031 return secondaries;
1032 }
1033 }
1035 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1036 if (k->is_interface()) {
1037 return implements_interface(k);
1038 } else {
1039 return Klass::compute_is_subtype_of(k);
1040 }
1041 }
1043 bool InstanceKlass::implements_interface(Klass* k) const {
1044 if (this == k) return true;
1045 assert(k->is_interface(), "should be an interface class");
1046 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1047 if (transitive_interfaces()->at(i) == k) {
1048 return true;
1049 }
1050 }
1051 return false;
1052 }
1054 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1055 // Verify direct super interface
1056 if (this == k) return true;
1057 assert(k->is_interface(), "should be an interface class");
1058 for (int i = 0; i < local_interfaces()->length(); i++) {
1059 if (local_interfaces()->at(i) == k) {
1060 return true;
1061 }
1062 }
1063 return false;
1064 }
1066 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1067 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1068 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1069 report_java_out_of_memory("Requested array size exceeds VM limit");
1070 JvmtiExport::post_array_size_exhausted();
1071 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1072 }
1073 int size = objArrayOopDesc::object_size(length);
1074 Klass* ak = array_klass(n, CHECK_NULL);
1075 KlassHandle h_ak (THREAD, ak);
1076 objArrayOop o =
1077 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1078 return o;
1079 }
1081 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1082 if (TraceFinalizerRegistration) {
1083 tty->print("Registered ");
1084 i->print_value_on(tty);
1085 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
1086 }
1087 instanceHandle h_i(THREAD, i);
1088 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1089 JavaValue result(T_VOID);
1090 JavaCallArguments args(h_i);
1091 methodHandle mh (THREAD, Universe::finalizer_register_method());
1092 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1093 return h_i();
1094 }
1096 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1097 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1098 int size = size_helper(); // Query before forming handle.
1100 KlassHandle h_k(THREAD, this);
1102 instanceOop i;
1104 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1105 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1106 i = register_finalizer(i, CHECK_NULL);
1107 }
1108 return i;
1109 }
1111 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1112 if (is_interface() || is_abstract()) {
1113 ResourceMark rm(THREAD);
1114 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1115 : vmSymbols::java_lang_InstantiationException(), external_name());
1116 }
1117 if (this == SystemDictionary::Class_klass()) {
1118 ResourceMark rm(THREAD);
1119 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1120 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1121 }
1122 }
1124 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1125 instanceKlassHandle this_oop(THREAD, this);
1126 return array_klass_impl(this_oop, or_null, n, THREAD);
1127 }
1129 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
1130 if (this_oop->array_klasses() == NULL) {
1131 if (or_null) return NULL;
1133 ResourceMark rm;
1134 JavaThread *jt = (JavaThread *)THREAD;
1135 {
1136 // Atomic creation of array_klasses
1137 MutexLocker mc(Compile_lock, THREAD); // for vtables
1138 MutexLocker ma(MultiArray_lock, THREAD);
1140 // Check if update has already taken place
1141 if (this_oop->array_klasses() == NULL) {
1142 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_oop->class_loader_data(), 1, this_oop, CHECK_NULL);
1143 this_oop->set_array_klasses(k);
1144 }
1145 }
1146 }
1147 // _this will always be set at this point
1148 ObjArrayKlass* oak = (ObjArrayKlass*)this_oop->array_klasses();
1149 if (or_null) {
1150 return oak->array_klass_or_null(n);
1151 }
1152 return oak->array_klass(n, CHECK_NULL);
1153 }
1155 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1156 return array_klass_impl(or_null, 1, THREAD);
1157 }
1159 void InstanceKlass::call_class_initializer(TRAPS) {
1160 instanceKlassHandle ik (THREAD, this);
1161 call_class_initializer_impl(ik, THREAD);
1162 }
1164 static int call_class_initializer_impl_counter = 0; // for debugging
1166 Method* InstanceKlass::class_initializer() {
1167 Method* clinit = find_method(
1168 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1169 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1170 return clinit;
1171 }
1172 return NULL;
1173 }
1175 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
1176 if (ReplayCompiles &&
1177 (ReplaySuppressInitializers == 1 ||
1178 ReplaySuppressInitializers >= 2 && this_oop->class_loader() != NULL)) {
1179 // Hide the existence of the initializer for the purpose of replaying the compile
1180 return;
1181 }
1183 methodHandle h_method(THREAD, this_oop->class_initializer());
1184 assert(!this_oop->is_initialized(), "we cannot initialize twice");
1185 if (TraceClassInitialization) {
1186 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1187 this_oop->name()->print_value();
1188 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
1189 }
1190 if (h_method() != NULL) {
1191 JavaCallArguments args; // No arguments
1192 JavaValue result(T_VOID);
1193 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1194 }
1195 }
1198 void InstanceKlass::mask_for(methodHandle method, int bci,
1199 InterpreterOopMap* entry_for) {
1200 // Dirty read, then double-check under a lock.
1201 if (_oop_map_cache == NULL) {
1202 // Otherwise, allocate a new one.
1203 MutexLocker x(OopMapCacheAlloc_lock);
1204 // First time use. Allocate a cache in C heap
1205 if (_oop_map_cache == NULL) {
1206 // Release stores from OopMapCache constructor before assignment
1207 // to _oop_map_cache. C++ compilers on ppc do not emit the
1208 // required memory barrier only because of the volatile
1209 // qualifier of _oop_map_cache.
1210 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1211 }
1212 }
1213 // _oop_map_cache is constant after init; lookup below does is own locking.
1214 _oop_map_cache->lookup(method, bci, entry_for);
1215 }
1218 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1219 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1220 Symbol* f_name = fs.name();
1221 Symbol* f_sig = fs.signature();
1222 if (f_name == name && f_sig == sig) {
1223 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1224 return true;
1225 }
1226 }
1227 return false;
1228 }
1231 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1232 const int n = local_interfaces()->length();
1233 for (int i = 0; i < n; i++) {
1234 Klass* intf1 = local_interfaces()->at(i);
1235 assert(intf1->is_interface(), "just checking type");
1236 // search for field in current interface
1237 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1238 assert(fd->is_static(), "interface field must be static");
1239 return intf1;
1240 }
1241 // search for field in direct superinterfaces
1242 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1243 if (intf2 != NULL) return intf2;
1244 }
1245 // otherwise field lookup fails
1246 return NULL;
1247 }
1250 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1251 // search order according to newest JVM spec (5.4.3.2, p.167).
1252 // 1) search for field in current klass
1253 if (find_local_field(name, sig, fd)) {
1254 return const_cast<InstanceKlass*>(this);
1255 }
1256 // 2) search for field recursively in direct superinterfaces
1257 { Klass* intf = find_interface_field(name, sig, fd);
1258 if (intf != NULL) return intf;
1259 }
1260 // 3) apply field lookup recursively if superclass exists
1261 { Klass* supr = super();
1262 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1263 }
1264 // 4) otherwise field lookup fails
1265 return NULL;
1266 }
1269 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1270 // search order according to newest JVM spec (5.4.3.2, p.167).
1271 // 1) search for field in current klass
1272 if (find_local_field(name, sig, fd)) {
1273 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1274 }
1275 // 2) search for field recursively in direct superinterfaces
1276 if (is_static) {
1277 Klass* intf = find_interface_field(name, sig, fd);
1278 if (intf != NULL) return intf;
1279 }
1280 // 3) apply field lookup recursively if superclass exists
1281 { Klass* supr = super();
1282 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1283 }
1284 // 4) otherwise field lookup fails
1285 return NULL;
1286 }
1289 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1290 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1291 if (fs.offset() == offset) {
1292 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1293 if (fd->is_static() == is_static) return true;
1294 }
1295 }
1296 return false;
1297 }
1300 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1301 Klass* klass = const_cast<InstanceKlass*>(this);
1302 while (klass != NULL) {
1303 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1304 return true;
1305 }
1306 klass = klass->super();
1307 }
1308 return false;
1309 }
1312 void InstanceKlass::methods_do(void f(Method* method)) {
1313 int len = methods()->length();
1314 for (int index = 0; index < len; index++) {
1315 Method* m = methods()->at(index);
1316 assert(m->is_method(), "must be method");
1317 f(m);
1318 }
1319 }
1322 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1323 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1324 if (fs.access_flags().is_static()) {
1325 fieldDescriptor& fd = fs.field_descriptor();
1326 cl->do_field(&fd);
1327 }
1328 }
1329 }
1332 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1333 instanceKlassHandle h_this(THREAD, this);
1334 do_local_static_fields_impl(h_this, f, mirror, CHECK);
1335 }
1338 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1339 void f(fieldDescriptor* fd, Handle mirror, TRAPS), Handle mirror, TRAPS) {
1340 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1341 if (fs.access_flags().is_static()) {
1342 fieldDescriptor& fd = fs.field_descriptor();
1343 f(&fd, mirror, CHECK);
1344 }
1345 }
1346 }
1349 static int compare_fields_by_offset(int* a, int* b) {
1350 return a[0] - b[0];
1351 }
1353 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1354 InstanceKlass* super = superklass();
1355 if (super != NULL) {
1356 super->do_nonstatic_fields(cl);
1357 }
1358 fieldDescriptor fd;
1359 int length = java_fields_count();
1360 // In DebugInfo nonstatic fields are sorted by offset.
1361 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1362 int j = 0;
1363 for (int i = 0; i < length; i += 1) {
1364 fd.reinitialize(this, i);
1365 if (!fd.is_static()) {
1366 fields_sorted[j + 0] = fd.offset();
1367 fields_sorted[j + 1] = i;
1368 j += 2;
1369 }
1370 }
1371 if (j > 0) {
1372 length = j;
1373 // _sort_Fn is defined in growableArray.hpp.
1374 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1375 for (int i = 0; i < length; i += 2) {
1376 fd.reinitialize(this, fields_sorted[i + 1]);
1377 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1378 cl->do_field(&fd);
1379 }
1380 }
1381 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1382 }
1385 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1386 if (array_klasses() != NULL)
1387 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1388 }
1390 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1391 if (array_klasses() != NULL)
1392 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1393 }
1395 #ifdef ASSERT
1396 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1397 int len = methods->length();
1398 for (int index = 0; index < len; index++) {
1399 Method* m = methods->at(index);
1400 assert(m->is_method(), "must be method");
1401 if (m->signature() == signature && m->name() == name) {
1402 return index;
1403 }
1404 }
1405 return -1;
1406 }
1407 #endif
1409 static int binary_search(Array<Method*>* methods, Symbol* name) {
1410 int len = methods->length();
1411 // methods are sorted, so do binary search
1412 int l = 0;
1413 int h = len - 1;
1414 while (l <= h) {
1415 int mid = (l + h) >> 1;
1416 Method* m = methods->at(mid);
1417 assert(m->is_method(), "must be method");
1418 int res = m->name()->fast_compare(name);
1419 if (res == 0) {
1420 return mid;
1421 } else if (res < 0) {
1422 l = mid + 1;
1423 } else {
1424 h = mid - 1;
1425 }
1426 }
1427 return -1;
1428 }
1430 // find_method looks up the name/signature in the local methods array
1431 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1432 return find_method_impl(name, signature, false);
1433 }
1435 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const {
1436 return InstanceKlass::find_method_impl(methods(), name, signature, skipping_overpass);
1437 }
1439 // find_instance_method looks up the name/signature in the local methods array
1440 // and skips over static methods
1441 Method* InstanceKlass::find_instance_method(
1442 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1443 Method* meth = InstanceKlass::find_method(methods, name, signature);
1444 if (meth != NULL && meth->is_static()) {
1445 meth = NULL;
1446 }
1447 return meth;
1448 }
1450 // find_method looks up the name/signature in the local methods array
1451 Method* InstanceKlass::find_method(
1452 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1453 return InstanceKlass::find_method_impl(methods, name, signature, false);
1454 }
1456 Method* InstanceKlass::find_method_impl(
1457 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1458 int hit = find_method_index(methods, name, signature, skipping_overpass);
1459 return hit >= 0 ? methods->at(hit): NULL;
1460 }
1462 // Used directly for default_methods to find the index into the
1463 // default_vtable_indices, and indirectly by find_method
1464 // find_method_index looks in the local methods array to return the index
1465 // of the matching name/signature. If, overpass methods are being ignored,
1466 // the search continues to find a potential non-overpass match. This capability
1467 // is important during method resolution to prefer a static method, for example,
1468 // over an overpass method.
1469 int InstanceKlass::find_method_index(
1470 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
1471 int hit = binary_search(methods, name);
1472 if (hit != -1) {
1473 Method* m = methods->at(hit);
1474 // Do linear search to find matching signature. First, quick check
1475 // for common case, ignoring overpasses if requested.
1476 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return hit;
1478 // search downwards through overloaded methods
1479 int i;
1480 for (i = hit - 1; i >= 0; --i) {
1481 Method* m = methods->at(i);
1482 assert(m->is_method(), "must be method");
1483 if (m->name() != name) break;
1484 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1485 }
1486 // search upwards
1487 for (i = hit + 1; i < methods->length(); ++i) {
1488 Method* m = methods->at(i);
1489 assert(m->is_method(), "must be method");
1490 if (m->name() != name) break;
1491 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
1492 }
1493 // not found
1494 #ifdef ASSERT
1495 int index = skipping_overpass ? -1 : linear_search(methods, name, signature);
1496 assert(index == -1, err_msg("binary search should have found entry %d", index));
1497 #endif
1498 }
1499 return -1;
1500 }
1501 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1502 return find_method_by_name(methods(), name, end);
1503 }
1505 int InstanceKlass::find_method_by_name(
1506 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1507 assert(end_ptr != NULL, "just checking");
1508 int start = binary_search(methods, name);
1509 int end = start + 1;
1510 if (start != -1) {
1511 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1512 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1513 *end_ptr = end;
1514 return start;
1515 }
1516 return -1;
1517 }
1519 // uncached_lookup_method searches both the local class methods array and all
1520 // superclasses methods arrays, skipping any overpass methods in superclasses.
1521 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const {
1522 MethodLookupMode lookup_mode = mode;
1523 Klass* klass = const_cast<InstanceKlass*>(this);
1524 while (klass != NULL) {
1525 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, (lookup_mode == skip_overpass));
1526 if (method != NULL) {
1527 return method;
1528 }
1529 klass = InstanceKlass::cast(klass)->super();
1530 lookup_mode = skip_overpass; // Always ignore overpass methods in superclasses
1531 }
1532 return NULL;
1533 }
1535 // lookup a method in the default methods list then in all transitive interfaces
1536 // Do NOT return private or static methods
1537 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1538 Symbol* signature) const {
1539 Method* m = NULL;
1540 if (default_methods() != NULL) {
1541 m = find_method(default_methods(), name, signature);
1542 }
1543 // Look up interfaces
1544 if (m == NULL) {
1545 m = lookup_method_in_all_interfaces(name, signature, normal);
1546 }
1547 return m;
1548 }
1550 // lookup a method in all the interfaces that this class implements
1551 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1552 // They should only be found in the initial InterfaceMethodRef
1553 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1554 Symbol* signature,
1555 MethodLookupMode mode) const {
1556 Array<Klass*>* all_ifs = transitive_interfaces();
1557 int num_ifs = all_ifs->length();
1558 InstanceKlass *ik = NULL;
1559 for (int i = 0; i < num_ifs; i++) {
1560 ik = InstanceKlass::cast(all_ifs->at(i));
1561 Method* m = ik->lookup_method(name, signature);
1562 if (m != NULL && m->is_public() && !m->is_static() &&
1563 ((mode != skip_defaults) || !m->is_default_method())) {
1564 return m;
1565 }
1566 }
1567 return NULL;
1568 }
1570 /* jni_id_for_impl for jfieldIds only */
1571 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1572 MutexLocker ml(JfieldIdCreation_lock);
1573 // Retry lookup after we got the lock
1574 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1575 if (probe == NULL) {
1576 // Slow case, allocate new static field identifier
1577 probe = new JNIid(this_oop(), offset, this_oop->jni_ids());
1578 this_oop->set_jni_ids(probe);
1579 }
1580 return probe;
1581 }
1584 /* jni_id_for for jfieldIds only */
1585 JNIid* InstanceKlass::jni_id_for(int offset) {
1586 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1587 if (probe == NULL) {
1588 probe = jni_id_for_impl(this, offset);
1589 }
1590 return probe;
1591 }
1593 u2 InstanceKlass::enclosing_method_data(int offset) {
1594 Array<jushort>* inner_class_list = inner_classes();
1595 if (inner_class_list == NULL) {
1596 return 0;
1597 }
1598 int length = inner_class_list->length();
1599 if (length % inner_class_next_offset == 0) {
1600 return 0;
1601 } else {
1602 int index = length - enclosing_method_attribute_size;
1603 assert(offset < enclosing_method_attribute_size, "invalid offset");
1604 return inner_class_list->at(index + offset);
1605 }
1606 }
1608 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1609 u2 method_index) {
1610 Array<jushort>* inner_class_list = inner_classes();
1611 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1612 int length = inner_class_list->length();
1613 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1614 int index = length - enclosing_method_attribute_size;
1615 inner_class_list->at_put(
1616 index + enclosing_method_class_index_offset, class_index);
1617 inner_class_list->at_put(
1618 index + enclosing_method_method_index_offset, method_index);
1619 }
1620 }
1622 // Lookup or create a jmethodID.
1623 // This code is called by the VMThread and JavaThreads so the
1624 // locking has to be done very carefully to avoid deadlocks
1625 // and/or other cache consistency problems.
1626 //
1627 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1628 size_t idnum = (size_t)method_h->method_idnum();
1629 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1630 size_t length = 0;
1631 jmethodID id = NULL;
1633 // We use a double-check locking idiom here because this cache is
1634 // performance sensitive. In the normal system, this cache only
1635 // transitions from NULL to non-NULL which is safe because we use
1636 // release_set_methods_jmethod_ids() to advertise the new cache.
1637 // A partially constructed cache should never be seen by a racing
1638 // thread. We also use release_store_ptr() to save a new jmethodID
1639 // in the cache so a partially constructed jmethodID should never be
1640 // seen either. Cache reads of existing jmethodIDs proceed without a
1641 // lock, but cache writes of a new jmethodID requires uniqueness and
1642 // creation of the cache itself requires no leaks so a lock is
1643 // generally acquired in those two cases.
1644 //
1645 // If the RedefineClasses() API has been used, then this cache can
1646 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1647 // Cache creation requires no leaks and we require safety between all
1648 // cache accesses and freeing of the old cache so a lock is generally
1649 // acquired when the RedefineClasses() API has been used.
1651 if (jmeths != NULL) {
1652 // the cache already exists
1653 if (!ik_h->idnum_can_increment()) {
1654 // the cache can't grow so we can just get the current values
1655 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1656 } else {
1657 // cache can grow so we have to be more careful
1658 if (Threads::number_of_threads() == 0 ||
1659 SafepointSynchronize::is_at_safepoint()) {
1660 // we're single threaded or at a safepoint - no locking needed
1661 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1662 } else {
1663 MutexLocker ml(JmethodIdCreation_lock);
1664 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1665 }
1666 }
1667 }
1668 // implied else:
1669 // we need to allocate a cache so default length and id values are good
1671 if (jmeths == NULL || // no cache yet
1672 length <= idnum || // cache is too short
1673 id == NULL) { // cache doesn't contain entry
1675 // This function can be called by the VMThread so we have to do all
1676 // things that might block on a safepoint before grabbing the lock.
1677 // Otherwise, we can deadlock with the VMThread or have a cache
1678 // consistency issue. These vars keep track of what we might have
1679 // to free after the lock is dropped.
1680 jmethodID to_dealloc_id = NULL;
1681 jmethodID* to_dealloc_jmeths = NULL;
1683 // may not allocate new_jmeths or use it if we allocate it
1684 jmethodID* new_jmeths = NULL;
1685 if (length <= idnum) {
1686 // allocate a new cache that might be used
1687 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1688 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1689 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1690 // cache size is stored in element[0], other elements offset by one
1691 new_jmeths[0] = (jmethodID)size;
1692 }
1694 // allocate a new jmethodID that might be used
1695 jmethodID new_id = NULL;
1696 if (method_h->is_old() && !method_h->is_obsolete()) {
1697 // The method passed in is old (but not obsolete), we need to use the current version
1698 Method* current_method = ik_h->method_with_idnum((int)idnum);
1699 assert(current_method != NULL, "old and but not obsolete, so should exist");
1700 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1701 } else {
1702 // It is the current version of the method or an obsolete method,
1703 // use the version passed in
1704 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1705 }
1707 if (Threads::number_of_threads() == 0 ||
1708 SafepointSynchronize::is_at_safepoint()) {
1709 // we're single threaded or at a safepoint - no locking needed
1710 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1711 &to_dealloc_id, &to_dealloc_jmeths);
1712 } else {
1713 MutexLocker ml(JmethodIdCreation_lock);
1714 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1715 &to_dealloc_id, &to_dealloc_jmeths);
1716 }
1718 // The lock has been dropped so we can free resources.
1719 // Free up either the old cache or the new cache if we allocated one.
1720 if (to_dealloc_jmeths != NULL) {
1721 FreeHeap(to_dealloc_jmeths);
1722 }
1723 // free up the new ID since it wasn't needed
1724 if (to_dealloc_id != NULL) {
1725 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1726 }
1727 }
1728 return id;
1729 }
1732 // Common code to fetch the jmethodID from the cache or update the
1733 // cache with the new jmethodID. This function should never do anything
1734 // that causes the caller to go to a safepoint or we can deadlock with
1735 // the VMThread or have cache consistency issues.
1736 //
1737 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1738 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1739 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1740 jmethodID** to_dealloc_jmeths_p) {
1741 assert(new_id != NULL, "sanity check");
1742 assert(to_dealloc_id_p != NULL, "sanity check");
1743 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1744 assert(Threads::number_of_threads() == 0 ||
1745 SafepointSynchronize::is_at_safepoint() ||
1746 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1748 // reacquire the cache - we are locked, single threaded or at a safepoint
1749 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1750 jmethodID id = NULL;
1751 size_t length = 0;
1753 if (jmeths == NULL || // no cache yet
1754 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1755 if (jmeths != NULL) {
1756 // copy any existing entries from the old cache
1757 for (size_t index = 0; index < length; index++) {
1758 new_jmeths[index+1] = jmeths[index+1];
1759 }
1760 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1761 }
1762 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1763 } else {
1764 // fetch jmethodID (if any) from the existing cache
1765 id = jmeths[idnum+1];
1766 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1767 }
1768 if (id == NULL) {
1769 // No matching jmethodID in the existing cache or we have a new
1770 // cache or we just grew the cache. This cache write is done here
1771 // by the first thread to win the foot race because a jmethodID
1772 // needs to be unique once it is generally available.
1773 id = new_id;
1775 // The jmethodID cache can be read while unlocked so we have to
1776 // make sure the new jmethodID is complete before installing it
1777 // in the cache.
1778 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1779 } else {
1780 *to_dealloc_id_p = new_id; // save new id for later delete
1781 }
1782 return id;
1783 }
1786 // Common code to get the jmethodID cache length and the jmethodID
1787 // value at index idnum if there is one.
1788 //
1789 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1790 size_t idnum, size_t *length_p, jmethodID* id_p) {
1791 assert(cache != NULL, "sanity check");
1792 assert(length_p != NULL, "sanity check");
1793 assert(id_p != NULL, "sanity check");
1795 // cache size is stored in element[0], other elements offset by one
1796 *length_p = (size_t)cache[0];
1797 if (*length_p <= idnum) { // cache is too short
1798 *id_p = NULL;
1799 } else {
1800 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1801 }
1802 }
1805 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1806 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1807 size_t idnum = (size_t)method->method_idnum();
1808 jmethodID* jmeths = methods_jmethod_ids_acquire();
1809 size_t length; // length assigned as debugging crumb
1810 jmethodID id = NULL;
1811 if (jmeths != NULL && // If there is a cache
1812 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1813 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1814 }
1815 return id;
1816 }
1819 //
1820 // Walk the list of dependent nmethods searching for nmethods which
1821 // are dependent on the changes that were passed in and mark them for
1822 // deoptimization. Returns the number of nmethods found.
1823 //
1824 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1825 assert_locked_or_safepoint(CodeCache_lock);
1826 int found = 0;
1827 nmethodBucket* b = _dependencies;
1828 while (b != NULL) {
1829 nmethod* nm = b->get_nmethod();
1830 // since dependencies aren't removed until an nmethod becomes a zombie,
1831 // the dependency list may contain nmethods which aren't alive.
1832 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1833 if (TraceDependencies) {
1834 ResourceMark rm;
1835 tty->print_cr("Marked for deoptimization");
1836 tty->print_cr(" context = %s", this->external_name());
1837 changes.print();
1838 nm->print();
1839 nm->print_dependencies();
1840 }
1841 nm->mark_for_deoptimization();
1842 found++;
1843 }
1844 b = b->next();
1845 }
1846 return found;
1847 }
1850 //
1851 // Add an nmethodBucket to the list of dependencies for this nmethod.
1852 // It's possible that an nmethod has multiple dependencies on this klass
1853 // so a count is kept for each bucket to guarantee that creation and
1854 // deletion of dependencies is consistent.
1855 //
1856 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1857 assert_locked_or_safepoint(CodeCache_lock);
1858 nmethodBucket* b = _dependencies;
1859 nmethodBucket* last = NULL;
1860 while (b != NULL) {
1861 if (nm == b->get_nmethod()) {
1862 b->increment();
1863 return;
1864 }
1865 b = b->next();
1866 }
1867 _dependencies = new nmethodBucket(nm, _dependencies);
1868 }
1871 //
1872 // Decrement count of the nmethod in the dependency list and remove
1873 // the bucket competely when the count goes to 0. This method must
1874 // find a corresponding bucket otherwise there's a bug in the
1875 // recording of dependecies.
1876 //
1877 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1878 assert_locked_or_safepoint(CodeCache_lock);
1879 nmethodBucket* b = _dependencies;
1880 nmethodBucket* last = NULL;
1881 while (b != NULL) {
1882 if (nm == b->get_nmethod()) {
1883 if (b->decrement() == 0) {
1884 if (last == NULL) {
1885 _dependencies = b->next();
1886 } else {
1887 last->set_next(b->next());
1888 }
1889 delete b;
1890 }
1891 return;
1892 }
1893 last = b;
1894 b = b->next();
1895 }
1896 #ifdef ASSERT
1897 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1898 nm->print();
1899 #endif // ASSERT
1900 ShouldNotReachHere();
1901 }
1904 #ifndef PRODUCT
1905 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1906 nmethodBucket* b = _dependencies;
1907 int idx = 0;
1908 while (b != NULL) {
1909 nmethod* nm = b->get_nmethod();
1910 tty->print("[%d] count=%d { ", idx++, b->count());
1911 if (!verbose) {
1912 nm->print_on(tty, "nmethod");
1913 tty->print_cr(" } ");
1914 } else {
1915 nm->print();
1916 nm->print_dependencies();
1917 tty->print_cr("--- } ");
1918 }
1919 b = b->next();
1920 }
1921 }
1924 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1925 nmethodBucket* b = _dependencies;
1926 while (b != NULL) {
1927 if (nm == b->get_nmethod()) {
1928 return true;
1929 }
1930 b = b->next();
1931 }
1932 return false;
1933 }
1934 #endif //PRODUCT
1937 // Garbage collection
1939 #ifdef ASSERT
1940 template <class T> void assert_is_in(T *p) {
1941 T heap_oop = oopDesc::load_heap_oop(p);
1942 if (!oopDesc::is_null(heap_oop)) {
1943 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1944 assert(Universe::heap()->is_in(o), "should be in heap");
1945 }
1946 }
1947 template <class T> void assert_is_in_closed_subset(T *p) {
1948 T heap_oop = oopDesc::load_heap_oop(p);
1949 if (!oopDesc::is_null(heap_oop)) {
1950 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1951 assert(Universe::heap()->is_in_closed_subset(o),
1952 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
1953 }
1954 }
1955 template <class T> void assert_is_in_reserved(T *p) {
1956 T heap_oop = oopDesc::load_heap_oop(p);
1957 if (!oopDesc::is_null(heap_oop)) {
1958 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1959 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1960 }
1961 }
1962 template <class T> void assert_nothing(T *p) {}
1964 #else
1965 template <class T> void assert_is_in(T *p) {}
1966 template <class T> void assert_is_in_closed_subset(T *p) {}
1967 template <class T> void assert_is_in_reserved(T *p) {}
1968 template <class T> void assert_nothing(T *p) {}
1969 #endif // ASSERT
1971 //
1972 // Macros that iterate over areas of oops which are specialized on type of
1973 // oop pointer either narrow or wide, depending on UseCompressedOops
1974 //
1975 // Parameters are:
1976 // T - type of oop to point to (either oop or narrowOop)
1977 // start_p - starting pointer for region to iterate over
1978 // count - number of oops or narrowOops to iterate over
1979 // do_oop - action to perform on each oop (it's arbitrary C code which
1980 // makes it more efficient to put in a macro rather than making
1981 // it a template function)
1982 // assert_fn - assert function which is template function because performance
1983 // doesn't matter when enabled.
1984 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1985 T, start_p, count, do_oop, \
1986 assert_fn) \
1987 { \
1988 T* p = (T*)(start_p); \
1989 T* const end = p + (count); \
1990 while (p < end) { \
1991 (assert_fn)(p); \
1992 do_oop; \
1993 ++p; \
1994 } \
1995 }
1997 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1998 T, start_p, count, do_oop, \
1999 assert_fn) \
2000 { \
2001 T* const start = (T*)(start_p); \
2002 T* p = start + (count); \
2003 while (start < p) { \
2004 --p; \
2005 (assert_fn)(p); \
2006 do_oop; \
2007 } \
2008 }
2010 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
2011 T, start_p, count, low, high, \
2012 do_oop, assert_fn) \
2013 { \
2014 T* const l = (T*)(low); \
2015 T* const h = (T*)(high); \
2016 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
2017 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
2018 "bounded region must be properly aligned"); \
2019 T* p = (T*)(start_p); \
2020 T* end = p + (count); \
2021 if (p < l) p = l; \
2022 if (end > h) end = h; \
2023 while (p < end) { \
2024 (assert_fn)(p); \
2025 do_oop; \
2026 ++p; \
2027 } \
2028 }
2031 // The following macros call specialized macros, passing either oop or
2032 // narrowOop as the specialization type. These test the UseCompressedOops
2033 // flag.
2034 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
2035 { \
2036 /* Compute oopmap block range. The common case \
2037 is nonstatic_oop_map_size == 1. */ \
2038 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2039 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2040 if (UseCompressedOops) { \
2041 while (map < end_map) { \
2042 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
2043 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2044 do_oop, assert_fn) \
2045 ++map; \
2046 } \
2047 } else { \
2048 while (map < end_map) { \
2049 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
2050 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2051 do_oop, assert_fn) \
2052 ++map; \
2053 } \
2054 } \
2055 }
2057 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
2058 { \
2059 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
2060 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
2061 if (UseCompressedOops) { \
2062 while (start_map < map) { \
2063 --map; \
2064 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
2065 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2066 do_oop, assert_fn) \
2067 } \
2068 } else { \
2069 while (start_map < map) { \
2070 --map; \
2071 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
2072 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2073 do_oop, assert_fn) \
2074 } \
2075 } \
2076 }
2078 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
2079 assert_fn) \
2080 { \
2081 /* Compute oopmap block range. The common case is \
2082 nonstatic_oop_map_size == 1, so we accept the \
2083 usually non-existent extra overhead of examining \
2084 all the maps. */ \
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_BOUNDED_OOP_ITERATE(narrowOop, \
2090 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2091 low, high, \
2092 do_oop, assert_fn) \
2093 ++map; \
2094 } \
2095 } else { \
2096 while (map < end_map) { \
2097 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2098 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2099 low, high, \
2100 do_oop, assert_fn) \
2101 ++map; \
2102 } \
2103 } \
2104 }
2106 void InstanceKlass::oop_follow_contents(oop obj) {
2107 assert(obj != NULL, "can't follow the content of NULL object");
2108 MarkSweep::follow_klass(obj->klass());
2109 InstanceKlass_OOP_MAP_ITERATE( \
2110 obj, \
2111 MarkSweep::mark_and_push(p), \
2112 assert_is_in_closed_subset)
2113 }
2115 #if INCLUDE_ALL_GCS
2116 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2117 oop obj) {
2118 assert(obj != NULL, "can't follow the content of NULL object");
2119 PSParallelCompact::follow_klass(cm, obj->klass());
2120 // Only mark the header and let the scan of the meta-data mark
2121 // everything else.
2122 InstanceKlass_OOP_MAP_ITERATE( \
2123 obj, \
2124 PSParallelCompact::mark_and_push(cm, p), \
2125 assert_is_in)
2126 }
2127 #endif // INCLUDE_ALL_GCS
2129 // closure's do_metadata() method dictates whether the given closure should be
2130 // applied to the klass ptr in the object header.
2132 #define if_do_metadata_checked(closure, nv_suffix) \
2133 /* Make sure the non-virtual and the virtual versions match. */ \
2134 assert(closure->do_metadata##nv_suffix() == closure->do_metadata(), \
2135 "Inconsistency in do_metadata"); \
2136 if (closure->do_metadata##nv_suffix())
2138 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2139 \
2140 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2141 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2142 /* header */ \
2143 if_do_metadata_checked(closure, nv_suffix) { \
2144 closure->do_klass##nv_suffix(obj->klass()); \
2145 } \
2146 InstanceKlass_OOP_MAP_ITERATE( \
2147 obj, \
2148 SpecializationStats:: \
2149 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2150 (closure)->do_oop##nv_suffix(p), \
2151 assert_is_in_closed_subset) \
2152 return size_helper(); \
2153 }
2155 #if INCLUDE_ALL_GCS
2156 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2157 \
2158 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2159 OopClosureType* closure) { \
2160 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2161 /* header */ \
2162 if_do_metadata_checked(closure, nv_suffix) { \
2163 closure->do_klass##nv_suffix(obj->klass()); \
2164 } \
2165 /* instance variables */ \
2166 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2167 obj, \
2168 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2169 (closure)->do_oop##nv_suffix(p), \
2170 assert_is_in_closed_subset) \
2171 return size_helper(); \
2172 }
2173 #endif // INCLUDE_ALL_GCS
2175 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2176 \
2177 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2178 OopClosureType* closure, \
2179 MemRegion mr) { \
2180 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2181 if_do_metadata_checked(closure, nv_suffix) { \
2182 if (mr.contains(obj)) { \
2183 closure->do_klass##nv_suffix(obj->klass()); \
2184 } \
2185 } \
2186 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2187 obj, mr.start(), mr.end(), \
2188 (closure)->do_oop##nv_suffix(p), \
2189 assert_is_in_closed_subset) \
2190 return size_helper(); \
2191 }
2193 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2194 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2195 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2196 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2197 #if INCLUDE_ALL_GCS
2198 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2199 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2200 #endif // INCLUDE_ALL_GCS
2202 int InstanceKlass::oop_adjust_pointers(oop obj) {
2203 int size = size_helper();
2204 InstanceKlass_OOP_MAP_ITERATE( \
2205 obj, \
2206 MarkSweep::adjust_pointer(p), \
2207 assert_is_in)
2208 return size;
2209 }
2211 #if INCLUDE_ALL_GCS
2212 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2213 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2214 obj, \
2215 if (PSScavenge::should_scavenge(p)) { \
2216 pm->claim_or_forward_depth(p); \
2217 }, \
2218 assert_nothing )
2219 }
2221 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2222 int size = size_helper();
2223 InstanceKlass_OOP_MAP_ITERATE( \
2224 obj, \
2225 PSParallelCompact::adjust_pointer(p), \
2226 assert_is_in)
2227 return size;
2228 }
2230 #endif // INCLUDE_ALL_GCS
2232 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2233 assert(is_loader_alive(is_alive), "this klass should be live");
2234 if (is_interface()) {
2235 if (ClassUnloading) {
2236 Klass* impl = implementor();
2237 if (impl != NULL) {
2238 if (!impl->is_loader_alive(is_alive)) {
2239 // remove this guy
2240 Klass** klass = adr_implementor();
2241 assert(klass != NULL, "null klass");
2242 if (klass != NULL) {
2243 *klass = NULL;
2244 }
2245 }
2246 }
2247 }
2248 }
2249 }
2251 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2252 for (int m = 0; m < methods()->length(); m++) {
2253 MethodData* mdo = methods()->at(m)->method_data();
2254 if (mdo != NULL) {
2255 mdo->clean_method_data(is_alive);
2256 }
2257 }
2258 }
2261 static void remove_unshareable_in_class(Klass* k) {
2262 // remove klass's unshareable info
2263 k->remove_unshareable_info();
2264 }
2266 void InstanceKlass::remove_unshareable_info() {
2267 Klass::remove_unshareable_info();
2268 // Unlink the class
2269 if (is_linked()) {
2270 unlink_class();
2271 }
2272 init_implementor();
2274 constants()->remove_unshareable_info();
2276 for (int i = 0; i < methods()->length(); i++) {
2277 Method* m = methods()->at(i);
2278 m->remove_unshareable_info();
2279 }
2281 // do array classes also.
2282 array_klasses_do(remove_unshareable_in_class);
2283 }
2285 void restore_unshareable_in_class(Klass* k, TRAPS) {
2286 k->restore_unshareable_info(CHECK);
2287 }
2289 void InstanceKlass::restore_unshareable_info(TRAPS) {
2290 Klass::restore_unshareable_info(CHECK);
2291 instanceKlassHandle ik(THREAD, this);
2293 Array<Method*>* methods = ik->methods();
2294 int num_methods = methods->length();
2295 for (int index2 = 0; index2 < num_methods; ++index2) {
2296 methodHandle m(THREAD, methods->at(index2));
2297 m->restore_unshareable_info(CHECK);
2298 }
2299 if (JvmtiExport::has_redefined_a_class()) {
2300 // Reinitialize vtable because RedefineClasses may have changed some
2301 // entries in this vtable for super classes so the CDS vtable might
2302 // point to old or obsolete entries. RedefineClasses doesn't fix up
2303 // vtables in the shared system dictionary, only the main one.
2304 // It also redefines the itable too so fix that too.
2305 ResourceMark rm(THREAD);
2306 ik->vtable()->initialize_vtable(false, CHECK);
2307 ik->itable()->initialize_itable(false, CHECK);
2308 }
2310 // restore constant pool resolved references
2311 ik->constants()->restore_unshareable_info(CHECK);
2313 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2314 }
2316 static void clear_all_breakpoints(Method* m) {
2317 m->clear_all_breakpoints();
2318 }
2321 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2322 // notify the debugger
2323 if (JvmtiExport::should_post_class_unload()) {
2324 JvmtiExport::post_class_unload(ik);
2325 }
2327 // notify ClassLoadingService of class unload
2328 ClassLoadingService::notify_class_unloaded(ik);
2329 }
2331 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2332 // Clean up C heap
2333 ik->release_C_heap_structures();
2334 ik->constants()->release_C_heap_structures();
2335 }
2337 void InstanceKlass::release_C_heap_structures() {
2339 // Can't release the constant pool here because the constant pool can be
2340 // deallocated separately from the InstanceKlass for default methods and
2341 // redefine classes.
2343 // Deallocate oop map cache
2344 if (_oop_map_cache != NULL) {
2345 delete _oop_map_cache;
2346 _oop_map_cache = NULL;
2347 }
2349 // Deallocate JNI identifiers for jfieldIDs
2350 JNIid::deallocate(jni_ids());
2351 set_jni_ids(NULL);
2353 jmethodID* jmeths = methods_jmethod_ids_acquire();
2354 if (jmeths != (jmethodID*)NULL) {
2355 release_set_methods_jmethod_ids(NULL);
2356 FreeHeap(jmeths);
2357 }
2359 // Deallocate MemberNameTable
2360 {
2361 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2362 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2363 MemberNameTable* mnt = member_names();
2364 if (mnt != NULL) {
2365 delete mnt;
2366 set_member_names(NULL);
2367 }
2368 }
2370 // release dependencies
2371 nmethodBucket* b = _dependencies;
2372 _dependencies = NULL;
2373 while (b != NULL) {
2374 nmethodBucket* next = b->next();
2375 delete b;
2376 b = next;
2377 }
2379 // Deallocate breakpoint records
2380 if (breakpoints() != 0x0) {
2381 methods_do(clear_all_breakpoints);
2382 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2383 }
2385 // deallocate information about previous versions
2386 if (_previous_versions != NULL) {
2387 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2388 PreviousVersionNode * pv_node = _previous_versions->at(i);
2389 delete pv_node;
2390 }
2391 delete _previous_versions;
2392 _previous_versions = NULL;
2393 }
2395 // deallocate the cached class file
2396 if (_cached_class_file != NULL) {
2397 os::free(_cached_class_file, mtClass);
2398 _cached_class_file = NULL;
2399 }
2401 // Decrement symbol reference counts associated with the unloaded class.
2402 if (_name != NULL) _name->decrement_refcount();
2403 // unreference array name derived from this class name (arrays of an unloaded
2404 // class can't be referenced anymore).
2405 if (_array_name != NULL) _array_name->decrement_refcount();
2406 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2408 assert(_total_instanceKlass_count >= 1, "Sanity check");
2409 Atomic::dec(&_total_instanceKlass_count);
2410 }
2412 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2413 if (array == NULL) {
2414 _source_debug_extension = NULL;
2415 } else {
2416 // Adding one to the attribute length in order to store a null terminator
2417 // character could cause an overflow because the attribute length is
2418 // already coded with an u4 in the classfile, but in practice, it's
2419 // unlikely to happen.
2420 assert((length+1) > length, "Overflow checking");
2421 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2422 for (int i = 0; i < length; i++) {
2423 sde[i] = array[i];
2424 }
2425 sde[length] = '\0';
2426 _source_debug_extension = sde;
2427 }
2428 }
2430 address InstanceKlass::static_field_addr(int offset) {
2431 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2432 }
2435 const char* InstanceKlass::signature_name() const {
2436 int hash_len = 0;
2437 char hash_buf[40];
2439 // If this is an anonymous class, append a hash to make the name unique
2440 if (is_anonymous()) {
2441 assert(EnableInvokeDynamic, "EnableInvokeDynamic was not set.");
2442 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2443 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
2444 hash_len = (int)strlen(hash_buf);
2445 }
2447 // Get the internal name as a c string
2448 const char* src = (const char*) (name()->as_C_string());
2449 const int src_length = (int)strlen(src);
2451 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2453 // Add L as type indicator
2454 int dest_index = 0;
2455 dest[dest_index++] = 'L';
2457 // Add the actual class name
2458 for (int src_index = 0; src_index < src_length; ) {
2459 dest[dest_index++] = src[src_index++];
2460 }
2462 // If we have a hash, append it
2463 for (int hash_index = 0; hash_index < hash_len; ) {
2464 dest[dest_index++] = hash_buf[hash_index++];
2465 }
2467 // Add the semicolon and the NULL
2468 dest[dest_index++] = ';';
2469 dest[dest_index] = '\0';
2470 return dest;
2471 }
2473 // different verisons of is_same_class_package
2474 bool InstanceKlass::is_same_class_package(Klass* class2) {
2475 Klass* class1 = this;
2476 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2477 Symbol* classname1 = class1->name();
2479 if (class2->oop_is_objArray()) {
2480 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2481 }
2482 oop classloader2;
2483 if (class2->oop_is_instance()) {
2484 classloader2 = InstanceKlass::cast(class2)->class_loader();
2485 } else {
2486 assert(class2->oop_is_typeArray(), "should be type array");
2487 classloader2 = NULL;
2488 }
2489 Symbol* classname2 = class2->name();
2491 return InstanceKlass::is_same_class_package(classloader1, classname1,
2492 classloader2, classname2);
2493 }
2495 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2496 Klass* class1 = this;
2497 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2498 Symbol* classname1 = class1->name();
2500 return InstanceKlass::is_same_class_package(classloader1, classname1,
2501 classloader2, classname2);
2502 }
2504 // return true if two classes are in the same package, classloader
2505 // and classname information is enough to determine a class's package
2506 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2507 oop class_loader2, Symbol* class_name2) {
2508 if (class_loader1 != class_loader2) {
2509 return false;
2510 } else if (class_name1 == class_name2) {
2511 return true; // skip painful bytewise comparison
2512 } else {
2513 ResourceMark rm;
2515 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2516 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2517 // Otherwise, we just compare jbyte values between the strings.
2518 const jbyte *name1 = class_name1->base();
2519 const jbyte *name2 = class_name2->base();
2521 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2522 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2524 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2525 // One of the two doesn't have a package. Only return true
2526 // if the other one also doesn't have a package.
2527 return last_slash1 == last_slash2;
2528 } else {
2529 // Skip over '['s
2530 if (*name1 == '[') {
2531 do {
2532 name1++;
2533 } while (*name1 == '[');
2534 if (*name1 != 'L') {
2535 // Something is terribly wrong. Shouldn't be here.
2536 return false;
2537 }
2538 }
2539 if (*name2 == '[') {
2540 do {
2541 name2++;
2542 } while (*name2 == '[');
2543 if (*name2 != 'L') {
2544 // Something is terribly wrong. Shouldn't be here.
2545 return false;
2546 }
2547 }
2549 // Check that package part is identical
2550 int length1 = last_slash1 - name1;
2551 int length2 = last_slash2 - name2;
2553 return UTF8::equal(name1, length1, name2, length2);
2554 }
2555 }
2556 }
2558 // Returns true iff super_method can be overridden by a method in targetclassname
2559 // See JSL 3rd edition 8.4.6.1
2560 // Assumes name-signature match
2561 // "this" is InstanceKlass of super_method which must exist
2562 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2563 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2564 // Private methods can not be overridden
2565 if (super_method->is_private()) {
2566 return false;
2567 }
2568 // If super method is accessible, then override
2569 if ((super_method->is_protected()) ||
2570 (super_method->is_public())) {
2571 return true;
2572 }
2573 // Package-private methods are not inherited outside of package
2574 assert(super_method->is_package_private(), "must be package private");
2575 return(is_same_class_package(targetclassloader(), targetclassname));
2576 }
2578 /* defined for now in jvm.cpp, for historical reasons *--
2579 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2580 Symbol*& simple_name_result, TRAPS) {
2581 ...
2582 }
2583 */
2585 // tell if two classes have the same enclosing class (at package level)
2586 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2587 Klass* class2_oop, TRAPS) {
2588 if (class2_oop == class1()) return true;
2589 if (!class2_oop->oop_is_instance()) return false;
2590 instanceKlassHandle class2(THREAD, class2_oop);
2592 // must be in same package before we try anything else
2593 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2594 return false;
2596 // As long as there is an outer1.getEnclosingClass,
2597 // shift the search outward.
2598 instanceKlassHandle outer1 = class1;
2599 for (;;) {
2600 // As we walk along, look for equalities between outer1 and class2.
2601 // Eventually, the walks will terminate as outer1 stops
2602 // at the top-level class around the original class.
2603 bool ignore_inner_is_member;
2604 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2605 CHECK_false);
2606 if (next == NULL) break;
2607 if (next == class2()) return true;
2608 outer1 = instanceKlassHandle(THREAD, next);
2609 }
2611 // Now do the same for class2.
2612 instanceKlassHandle outer2 = class2;
2613 for (;;) {
2614 bool ignore_inner_is_member;
2615 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2616 CHECK_false);
2617 if (next == NULL) break;
2618 // Might as well check the new outer against all available values.
2619 if (next == class1()) return true;
2620 if (next == outer1()) return true;
2621 outer2 = instanceKlassHandle(THREAD, next);
2622 }
2624 // If by this point we have not found an equality between the
2625 // two classes, we know they are in separate package members.
2626 return false;
2627 }
2630 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2631 jint access = access_flags().as_int();
2633 // But check if it happens to be member class.
2634 instanceKlassHandle ik(THREAD, this);
2635 InnerClassesIterator iter(ik);
2636 for (; !iter.done(); iter.next()) {
2637 int ioff = iter.inner_class_info_index();
2638 // Inner class attribute can be zero, skip it.
2639 // Strange but true: JVM spec. allows null inner class refs.
2640 if (ioff == 0) continue;
2642 // only look at classes that are already loaded
2643 // since we are looking for the flags for our self.
2644 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2645 if ((ik->name() == inner_name)) {
2646 // This is really a member class.
2647 access = iter.inner_access_flags();
2648 break;
2649 }
2650 }
2651 // Remember to strip ACC_SUPER bit
2652 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2653 }
2655 jint InstanceKlass::jvmti_class_status() const {
2656 jint result = 0;
2658 if (is_linked()) {
2659 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2660 }
2662 if (is_initialized()) {
2663 assert(is_linked(), "Class status is not consistent");
2664 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2665 }
2666 if (is_in_error_state()) {
2667 result |= JVMTI_CLASS_STATUS_ERROR;
2668 }
2669 return result;
2670 }
2672 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2673 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2674 int method_table_offset_in_words = ioe->offset()/wordSize;
2675 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2676 / itableOffsetEntry::size();
2678 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2679 // If the interface isn't implemented by the receiver class,
2680 // the VM should throw IncompatibleClassChangeError.
2681 if (cnt >= nof_interfaces) {
2682 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2683 }
2685 Klass* ik = ioe->interface_klass();
2686 if (ik == holder) break;
2687 }
2689 itableMethodEntry* ime = ioe->first_method_entry(this);
2690 Method* m = ime[index].method();
2691 if (m == NULL) {
2692 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2693 }
2694 return m;
2695 }
2698 #if INCLUDE_JVMTI
2699 // update default_methods for redefineclasses for methods that are
2700 // not yet in the vtable due to concurrent subclass define and superinterface
2701 // redefinition
2702 // Note: those in the vtable, should have been updated via adjust_method_entries
2703 void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods,
2704 int methods_length, bool* trace_name_printed) {
2705 // search the default_methods for uses of either obsolete or EMCP methods
2706 if (default_methods() != NULL) {
2707 for (int j = 0; j < methods_length; j++) {
2708 Method* old_method = old_methods[j];
2709 Method* new_method = new_methods[j];
2711 for (int index = 0; index < default_methods()->length(); index ++) {
2712 if (default_methods()->at(index) == old_method) {
2713 default_methods()->at_put(index, new_method);
2714 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2715 if (!(*trace_name_printed)) {
2716 // RC_TRACE_MESG macro has an embedded ResourceMark
2717 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2718 external_name(),
2719 old_method->method_holder()->external_name()));
2720 *trace_name_printed = true;
2721 }
2722 RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2723 new_method->name()->as_C_string(),
2724 new_method->signature()->as_C_string()));
2725 }
2726 }
2727 }
2728 }
2729 }
2730 }
2731 #endif // INCLUDE_JVMTI
2733 // On-stack replacement stuff
2734 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2735 // only one compilation can be active
2736 NEEDS_CLEANUP
2737 // This is a short non-blocking critical region, so the no safepoint check is ok.
2738 OsrList_lock->lock_without_safepoint_check();
2739 assert(n->is_osr_method(), "wrong kind of nmethod");
2740 n->set_osr_link(osr_nmethods_head());
2741 set_osr_nmethods_head(n);
2742 // Raise the highest osr level if necessary
2743 if (TieredCompilation) {
2744 Method* m = n->method();
2745 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2746 }
2747 // Remember to unlock again
2748 OsrList_lock->unlock();
2750 // Get rid of the osr methods for the same bci that have lower levels.
2751 if (TieredCompilation) {
2752 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2753 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2754 if (inv != NULL && inv->is_in_use()) {
2755 inv->make_not_entrant();
2756 }
2757 }
2758 }
2759 }
2762 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2763 // This is a short non-blocking critical region, so the no safepoint check is ok.
2764 OsrList_lock->lock_without_safepoint_check();
2765 assert(n->is_osr_method(), "wrong kind of nmethod");
2766 nmethod* last = NULL;
2767 nmethod* cur = osr_nmethods_head();
2768 int max_level = CompLevel_none; // Find the max comp level excluding n
2769 Method* m = n->method();
2770 // Search for match
2771 while(cur != NULL && cur != n) {
2772 if (TieredCompilation) {
2773 // Find max level before n
2774 max_level = MAX2(max_level, cur->comp_level());
2775 }
2776 last = cur;
2777 cur = cur->osr_link();
2778 }
2779 nmethod* next = NULL;
2780 if (cur == n) {
2781 next = cur->osr_link();
2782 if (last == NULL) {
2783 // Remove first element
2784 set_osr_nmethods_head(next);
2785 } else {
2786 last->set_osr_link(next);
2787 }
2788 }
2789 n->set_osr_link(NULL);
2790 if (TieredCompilation) {
2791 cur = next;
2792 while (cur != NULL) {
2793 // Find max level after n
2794 max_level = MAX2(max_level, cur->comp_level());
2795 cur = cur->osr_link();
2796 }
2797 m->set_highest_osr_comp_level(max_level);
2798 }
2799 // Remember to unlock again
2800 OsrList_lock->unlock();
2801 }
2803 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2804 // This is a short non-blocking critical region, so the no safepoint check is ok.
2805 OsrList_lock->lock_without_safepoint_check();
2806 nmethod* osr = osr_nmethods_head();
2807 nmethod* best = NULL;
2808 while (osr != NULL) {
2809 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2810 // There can be a time when a c1 osr method exists but we are waiting
2811 // for a c2 version. When c2 completes its osr nmethod we will trash
2812 // the c1 version and only be able to find the c2 version. However
2813 // while we overflow in the c1 code at back branches we don't want to
2814 // try and switch to the same code as we are already running
2816 if (osr->method() == m &&
2817 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2818 if (match_level) {
2819 if (osr->comp_level() == comp_level) {
2820 // Found a match - return it.
2821 OsrList_lock->unlock();
2822 return osr;
2823 }
2824 } else {
2825 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2826 if (osr->comp_level() == CompLevel_highest_tier) {
2827 // Found the best possible - return it.
2828 OsrList_lock->unlock();
2829 return osr;
2830 }
2831 best = osr;
2832 }
2833 }
2834 }
2835 osr = osr->osr_link();
2836 }
2837 OsrList_lock->unlock();
2838 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2839 return best;
2840 }
2841 return NULL;
2842 }
2844 void InstanceKlass::add_member_name(int index, Handle mem_name) {
2845 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2846 MutexLocker ml(MemberNameTable_lock);
2847 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2848 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2850 if (_member_names == NULL) {
2851 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2852 }
2853 _member_names->add_member_name(index, mem_name_wref);
2854 }
2856 oop InstanceKlass::get_member_name(int index) {
2857 MutexLocker ml(MemberNameTable_lock);
2858 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
2859 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2861 if (_member_names == NULL) {
2862 return NULL;
2863 }
2864 oop mem_name =_member_names->get_member_name(index);
2865 return mem_name;
2866 }
2868 // -----------------------------------------------------------------------------------------------------
2869 // Printing
2871 #ifndef PRODUCT
2873 #define BULLET " - "
2875 static const char* state_names[] = {
2876 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2877 };
2879 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2880 for (int i = 0; i < len; i++) {
2881 intptr_t e = start[i];
2882 st->print("%d : " INTPTR_FORMAT, i, e);
2883 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2884 st->print(" ");
2885 ((Metadata*)e)->print_value_on(st);
2886 }
2887 st->cr();
2888 }
2889 }
2891 void InstanceKlass::print_on(outputStream* st) const {
2892 assert(is_klass(), "must be klass");
2893 Klass::print_on(st);
2895 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2896 st->print(BULLET"klass size: %d", size()); st->cr();
2897 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2898 st->print(BULLET"state: "); st->print_cr(state_names[_init_state]);
2899 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2900 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2901 st->print(BULLET"sub: ");
2902 Klass* sub = subklass();
2903 int n;
2904 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2905 if (n < MaxSubklassPrintSize) {
2906 sub->print_value_on(st);
2907 st->print(" ");
2908 }
2909 }
2910 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2911 st->cr();
2913 if (is_interface()) {
2914 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2915 if (nof_implementors() == 1) {
2916 st->print_cr(BULLET"implementor: ");
2917 st->print(" ");
2918 implementor()->print_value_on(st);
2919 st->cr();
2920 }
2921 }
2923 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2924 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2925 if (Verbose || WizardMode) {
2926 Array<Method*>* method_array = methods();
2927 for (int i = 0; i < method_array->length(); i++) {
2928 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2929 }
2930 }
2931 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2932 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2933 if (Verbose && default_methods() != NULL) {
2934 Array<Method*>* method_array = default_methods();
2935 for (int i = 0; i < method_array->length(); i++) {
2936 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2937 }
2938 }
2939 if (default_vtable_indices() != NULL) {
2940 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2941 }
2942 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2943 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2944 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2945 if (class_loader_data() != NULL) {
2946 st->print(BULLET"class loader data: ");
2947 class_loader_data()->print_value_on(st);
2948 st->cr();
2949 }
2950 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2951 if (source_file_name() != NULL) {
2952 st->print(BULLET"source file: ");
2953 source_file_name()->print_value_on(st);
2954 st->cr();
2955 }
2956 if (source_debug_extension() != NULL) {
2957 st->print(BULLET"source debug extension: ");
2958 st->print("%s", source_debug_extension());
2959 st->cr();
2960 }
2961 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2962 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2963 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2964 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2965 {
2966 bool have_pv = false;
2967 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
2968 for (PreviousVersionNode * pv_node = pvw.next_previous_version();
2969 pv_node != NULL; pv_node = pvw.next_previous_version()) {
2970 if (!have_pv)
2971 st->print(BULLET"previous version: ");
2972 have_pv = true;
2973 pv_node->prev_constant_pool()->print_value_on(st);
2974 }
2975 if (have_pv) st->cr();
2976 } // pvw is cleaned up
2978 if (generic_signature() != NULL) {
2979 st->print(BULLET"generic signature: ");
2980 generic_signature()->print_value_on(st);
2981 st->cr();
2982 }
2983 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2984 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2985 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
2986 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2987 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
2988 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2989 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2990 FieldPrinter print_static_field(st);
2991 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2992 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2993 FieldPrinter print_nonstatic_field(st);
2994 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
2996 st->print(BULLET"non-static oop maps: ");
2997 OopMapBlock* map = start_of_nonstatic_oop_maps();
2998 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2999 while (map < end_map) {
3000 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3001 map++;
3002 }
3003 st->cr();
3004 }
3006 #endif //PRODUCT
3008 void InstanceKlass::print_value_on(outputStream* st) const {
3009 assert(is_klass(), "must be klass");
3010 if (Verbose || WizardMode) access_flags().print_on(st);
3011 name()->print_value_on(st);
3012 }
3014 #ifndef PRODUCT
3016 void FieldPrinter::do_field(fieldDescriptor* fd) {
3017 _st->print(BULLET);
3018 if (_obj == NULL) {
3019 fd->print_on(_st);
3020 _st->cr();
3021 } else {
3022 fd->print_on_for(_st, _obj);
3023 _st->cr();
3024 }
3025 }
3028 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3029 Klass::oop_print_on(obj, st);
3031 if (this == SystemDictionary::String_klass()) {
3032 typeArrayOop value = java_lang_String::value(obj);
3033 juint offset = java_lang_String::offset(obj);
3034 juint length = java_lang_String::length(obj);
3035 if (value != NULL &&
3036 value->is_typeArray() &&
3037 offset <= (juint) value->length() &&
3038 offset + length <= (juint) value->length()) {
3039 st->print(BULLET"string: ");
3040 Handle h_obj(obj);
3041 java_lang_String::print(h_obj, st);
3042 st->cr();
3043 if (!WizardMode) return; // that is enough
3044 }
3045 }
3047 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3048 FieldPrinter print_field(st, obj);
3049 do_nonstatic_fields(&print_field);
3051 if (this == SystemDictionary::Class_klass()) {
3052 st->print(BULLET"signature: ");
3053 java_lang_Class::print_signature(obj, st);
3054 st->cr();
3055 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3056 st->print(BULLET"fake entry for mirror: ");
3057 mirrored_klass->print_value_on_maybe_null(st);
3058 st->cr();
3059 Klass* array_klass = java_lang_Class::array_klass(obj);
3060 st->print(BULLET"fake entry for array: ");
3061 array_klass->print_value_on_maybe_null(st);
3062 st->cr();
3063 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3064 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3065 Klass* real_klass = java_lang_Class::as_Klass(obj);
3066 if (real_klass != NULL && real_klass->oop_is_instance()) {
3067 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3068 }
3069 } else if (this == SystemDictionary::MethodType_klass()) {
3070 st->print(BULLET"signature: ");
3071 java_lang_invoke_MethodType::print_signature(obj, st);
3072 st->cr();
3073 }
3074 }
3076 #endif //PRODUCT
3078 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3079 st->print("a ");
3080 name()->print_value_on(st);
3081 obj->print_address_on(st);
3082 if (this == SystemDictionary::String_klass()
3083 && java_lang_String::value(obj) != NULL) {
3084 ResourceMark rm;
3085 int len = java_lang_String::length(obj);
3086 int plen = (len < 24 ? len : 12);
3087 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3088 st->print(" = \"%s\"", str);
3089 if (len > plen)
3090 st->print("...[%d]", len);
3091 } else if (this == SystemDictionary::Class_klass()) {
3092 Klass* k = java_lang_Class::as_Klass(obj);
3093 st->print(" = ");
3094 if (k != NULL) {
3095 k->print_value_on(st);
3096 } else {
3097 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3098 st->print("%s", tname ? tname : "type?");
3099 }
3100 } else if (this == SystemDictionary::MethodType_klass()) {
3101 st->print(" = ");
3102 java_lang_invoke_MethodType::print_signature(obj, st);
3103 } else if (java_lang_boxing_object::is_instance(obj)) {
3104 st->print(" = ");
3105 java_lang_boxing_object::print(obj, st);
3106 } else if (this == SystemDictionary::LambdaForm_klass()) {
3107 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3108 if (vmentry != NULL) {
3109 st->print(" => ");
3110 vmentry->print_value_on(st);
3111 }
3112 } else if (this == SystemDictionary::MemberName_klass()) {
3113 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3114 if (vmtarget != NULL) {
3115 st->print(" = ");
3116 vmtarget->print_value_on(st);
3117 } else {
3118 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3119 st->print(".");
3120 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3121 }
3122 }
3123 }
3125 const char* InstanceKlass::internal_name() const {
3126 return external_name();
3127 }
3129 #if INCLUDE_SERVICES
3130 // Size Statistics
3131 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3132 Klass::collect_statistics(sz);
3134 sz->_inst_size = HeapWordSize * size_helper();
3135 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
3136 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
3137 sz->_nonstatic_oopmap_bytes = HeapWordSize *
3138 ((is_interface() || is_anonymous()) ?
3139 align_object_offset(nonstatic_oop_map_size()) :
3140 nonstatic_oop_map_size());
3142 int n = 0;
3143 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3144 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3145 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3146 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3147 n += (sz->_fields_bytes = sz->count_array(fields()));
3148 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3149 sz->_ro_bytes += n;
3151 const ConstantPool* cp = constants();
3152 if (cp) {
3153 cp->collect_statistics(sz);
3154 }
3156 const Annotations* anno = annotations();
3157 if (anno) {
3158 anno->collect_statistics(sz);
3159 }
3161 const Array<Method*>* methods_array = methods();
3162 if (methods()) {
3163 for (int i = 0; i < methods_array->length(); i++) {
3164 Method* method = methods_array->at(i);
3165 if (method) {
3166 sz->_method_count ++;
3167 method->collect_statistics(sz);
3168 }
3169 }
3170 }
3171 }
3172 #endif // INCLUDE_SERVICES
3174 // Verification
3176 class VerifyFieldClosure: public OopClosure {
3177 protected:
3178 template <class T> void do_oop_work(T* p) {
3179 oop obj = oopDesc::load_decode_heap_oop(p);
3180 if (!obj->is_oop_or_null()) {
3181 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
3182 Universe::print();
3183 guarantee(false, "boom");
3184 }
3185 }
3186 public:
3187 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3188 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3189 };
3191 void InstanceKlass::verify_on(outputStream* st) {
3192 #ifndef PRODUCT
3193 // Avoid redundant verifies, this really should be in product.
3194 if (_verify_count == Universe::verify_count()) return;
3195 _verify_count = Universe::verify_count();
3196 #endif
3198 // Verify Klass
3199 Klass::verify_on(st);
3201 // Verify that klass is present in ClassLoaderData
3202 guarantee(class_loader_data()->contains_klass(this),
3203 "this class isn't found in class loader data");
3205 // Verify vtables
3206 if (is_linked()) {
3207 ResourceMark rm;
3208 // $$$ This used to be done only for m/s collections. Doing it
3209 // always seemed a valid generalization. (DLD -- 6/00)
3210 vtable()->verify(st);
3211 }
3213 // Verify first subklass
3214 if (subklass_oop() != NULL) {
3215 guarantee(subklass_oop()->is_klass(), "should be klass");
3216 }
3218 // Verify siblings
3219 Klass* super = this->super();
3220 Klass* sib = next_sibling();
3221 if (sib != NULL) {
3222 if (sib == this) {
3223 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3224 }
3226 guarantee(sib->is_klass(), "should be klass");
3227 guarantee(sib->super() == super, "siblings should have same superklass");
3228 }
3230 // Verify implementor fields
3231 Klass* im = implementor();
3232 if (im != NULL) {
3233 guarantee(is_interface(), "only interfaces should have implementor set");
3234 guarantee(im->is_klass(), "should be klass");
3235 guarantee(!im->is_interface() || im == this,
3236 "implementors cannot be interfaces");
3237 }
3239 // Verify local interfaces
3240 if (local_interfaces()) {
3241 Array<Klass*>* local_interfaces = this->local_interfaces();
3242 for (int j = 0; j < local_interfaces->length(); j++) {
3243 Klass* e = local_interfaces->at(j);
3244 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3245 }
3246 }
3248 // Verify transitive interfaces
3249 if (transitive_interfaces() != NULL) {
3250 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3251 for (int j = 0; j < transitive_interfaces->length(); j++) {
3252 Klass* e = transitive_interfaces->at(j);
3253 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3254 }
3255 }
3257 // Verify methods
3258 if (methods() != NULL) {
3259 Array<Method*>* methods = this->methods();
3260 for (int j = 0; j < methods->length(); j++) {
3261 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3262 }
3263 for (int j = 0; j < methods->length() - 1; j++) {
3264 Method* m1 = methods->at(j);
3265 Method* m2 = methods->at(j + 1);
3266 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3267 }
3268 }
3270 // Verify method ordering
3271 if (method_ordering() != NULL) {
3272 Array<int>* method_ordering = this->method_ordering();
3273 int length = method_ordering->length();
3274 if (JvmtiExport::can_maintain_original_method_order() ||
3275 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3276 guarantee(length == methods()->length(), "invalid method ordering length");
3277 jlong sum = 0;
3278 for (int j = 0; j < length; j++) {
3279 int original_index = method_ordering->at(j);
3280 guarantee(original_index >= 0, "invalid method ordering index");
3281 guarantee(original_index < length, "invalid method ordering index");
3282 sum += original_index;
3283 }
3284 // Verify sum of indices 0,1,...,length-1
3285 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3286 } else {
3287 guarantee(length == 0, "invalid method ordering length");
3288 }
3289 }
3291 // Verify default methods
3292 if (default_methods() != NULL) {
3293 Array<Method*>* methods = this->default_methods();
3294 for (int j = 0; j < methods->length(); j++) {
3295 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3296 }
3297 for (int j = 0; j < methods->length() - 1; j++) {
3298 Method* m1 = methods->at(j);
3299 Method* m2 = methods->at(j + 1);
3300 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3301 }
3302 }
3304 // Verify JNI static field identifiers
3305 if (jni_ids() != NULL) {
3306 jni_ids()->verify(this);
3307 }
3309 // Verify other fields
3310 if (array_klasses() != NULL) {
3311 guarantee(array_klasses()->is_klass(), "should be klass");
3312 }
3313 if (constants() != NULL) {
3314 guarantee(constants()->is_constantPool(), "should be constant pool");
3315 }
3316 const Klass* host = host_klass();
3317 if (host != NULL) {
3318 guarantee(host->is_klass(), "should be klass");
3319 }
3320 }
3322 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3323 Klass::oop_verify_on(obj, st);
3324 VerifyFieldClosure blk;
3325 obj->oop_iterate_no_header(&blk);
3326 }
3329 // JNIid class for jfieldIDs only
3330 // Note to reviewers:
3331 // These JNI functions are just moved over to column 1 and not changed
3332 // in the compressed oops workspace.
3333 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3334 _holder = holder;
3335 _offset = offset;
3336 _next = next;
3337 debug_only(_is_static_field_id = false;)
3338 }
3341 JNIid* JNIid::find(int offset) {
3342 JNIid* current = this;
3343 while (current != NULL) {
3344 if (current->offset() == offset) return current;
3345 current = current->next();
3346 }
3347 return NULL;
3348 }
3350 void JNIid::deallocate(JNIid* current) {
3351 while (current != NULL) {
3352 JNIid* next = current->next();
3353 delete current;
3354 current = next;
3355 }
3356 }
3359 void JNIid::verify(Klass* holder) {
3360 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3361 int end_field_offset;
3362 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3364 JNIid* current = this;
3365 while (current != NULL) {
3366 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3367 #ifdef ASSERT
3368 int o = current->offset();
3369 if (current->is_static_field_id()) {
3370 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3371 }
3372 #endif
3373 current = current->next();
3374 }
3375 }
3378 #ifdef ASSERT
3379 void InstanceKlass::set_init_state(ClassState state) {
3380 bool good_state = is_shared() ? (_init_state <= state)
3381 : (_init_state < state);
3382 assert(good_state || state == allocated, "illegal state transition");
3383 _init_state = (u1)state;
3384 }
3385 #endif
3388 // RedefineClasses() support for previous versions:
3390 // Purge previous versions
3391 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3392 if (ik->previous_versions() != NULL) {
3393 // This klass has previous versions so see what we can cleanup
3394 // while it is safe to do so.
3396 int deleted_count = 0; // leave debugging breadcrumbs
3397 int live_count = 0;
3398 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3399 ClassLoaderData::the_null_class_loader_data() :
3400 ik->class_loader_data();
3402 // RC_TRACE macro has an embedded ResourceMark
3403 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3404 ik->external_name(), ik->previous_versions()->length()));
3406 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3407 // check the previous versions array
3408 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3409 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3410 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3412 ConstantPool* pvcp = cp_ref;
3413 if (!pvcp->on_stack()) {
3414 // If the constant pool isn't on stack, none of the methods
3415 // are executing. Delete all the methods, the constant pool and
3416 // and this previous version node.
3417 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3418 if (method_refs != NULL) {
3419 for (int j = method_refs->length() - 1; j >= 0; j--) {
3420 Method* method = method_refs->at(j);
3421 assert(method != NULL, "method ref was unexpectedly cleared");
3422 method_refs->remove_at(j);
3423 // method will be freed with associated class.
3424 }
3425 }
3426 // Remove the constant pool
3427 delete pv_node;
3428 // Since we are traversing the array backwards, we don't have to
3429 // do anything special with the index.
3430 ik->previous_versions()->remove_at(i);
3431 deleted_count++;
3432 continue;
3433 } else {
3434 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3435 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3436 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3437 live_count++;
3438 }
3440 // At least one method is live in this previous version, clean out
3441 // the others or mark them as obsolete.
3442 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3443 if (method_refs != NULL) {
3444 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3445 method_refs->length()));
3446 for (int j = method_refs->length() - 1; j >= 0; j--) {
3447 Method* method = method_refs->at(j);
3448 assert(method != NULL, "method ref was unexpectedly cleared");
3450 // Remove the emcp method if it's not executing
3451 // If it's been made obsolete by a redefinition of a non-emcp
3452 // method, mark it as obsolete but leave it to clean up later.
3453 if (!method->on_stack()) {
3454 method_refs->remove_at(j);
3455 } else if (emcp_method_count == 0) {
3456 method->set_is_obsolete();
3457 } else {
3458 // RC_TRACE macro has an embedded ResourceMark
3459 RC_TRACE(0x00000200,
3460 ("purge: %s(%s): prev method @%d in version @%d is alive",
3461 method->name()->as_C_string(),
3462 method->signature()->as_C_string(), j, i));
3463 }
3464 }
3465 }
3466 }
3467 assert(ik->previous_versions()->length() == live_count, "sanity check");
3468 RC_TRACE(0x00000200,
3469 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3470 deleted_count));
3471 }
3472 }
3474 // External interface for use during class unloading.
3475 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3476 // Call with >0 emcp methods since they are not currently being redefined.
3477 purge_previous_versions_internal(ik, 1);
3478 }
3481 // Potentially add an information node that contains pointers to the
3482 // interesting parts of the previous version of the_class.
3483 // This is also where we clean out any unused references.
3484 // Note that while we delete nodes from the _previous_versions
3485 // array, we never delete the array itself until the klass is
3486 // unloaded. The has_been_redefined() query depends on that fact.
3487 //
3488 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3489 BitMap* emcp_methods, int emcp_method_count) {
3490 assert(Thread::current()->is_VM_thread(),
3491 "only VMThread can add previous versions");
3493 if (_previous_versions == NULL) {
3494 // This is the first previous version so make some space.
3495 // Start with 2 elements under the assumption that the class
3496 // won't be redefined much.
3497 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3498 GrowableArray<PreviousVersionNode *>(2, true);
3499 }
3501 ConstantPool* cp_ref = ikh->constants();
3503 // RC_TRACE macro has an embedded ResourceMark
3504 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3505 "on_stack=%d",
3506 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3507 cp_ref->on_stack()));
3509 // If the constant pool for this previous version of the class
3510 // is not marked as being on the stack, then none of the methods
3511 // in this previous version of the class are on the stack so
3512 // we don't need to create a new PreviousVersionNode. However,
3513 // we still need to examine older previous versions below.
3514 Array<Method*>* old_methods = ikh->methods();
3516 if (cp_ref->on_stack()) {
3517 PreviousVersionNode * pv_node = NULL;
3518 if (emcp_method_count == 0) {
3519 // non-shared ConstantPool gets a reference
3520 pv_node = new PreviousVersionNode(cp_ref, NULL);
3521 RC_TRACE(0x00000400,
3522 ("add: all methods are obsolete; flushing any EMCP refs"));
3523 } else {
3524 int local_count = 0;
3525 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3526 GrowableArray<Method*>(emcp_method_count, true);
3527 for (int i = 0; i < old_methods->length(); i++) {
3528 if (emcp_methods->at(i)) {
3529 // this old method is EMCP. Save it only if it's on the stack
3530 Method* old_method = old_methods->at(i);
3531 if (old_method->on_stack()) {
3532 method_refs->append(old_method);
3533 }
3534 if (++local_count >= emcp_method_count) {
3535 // no more EMCP methods so bail out now
3536 break;
3537 }
3538 }
3539 }
3540 // non-shared ConstantPool gets a reference
3541 pv_node = new PreviousVersionNode(cp_ref, method_refs);
3542 }
3543 // append new previous version.
3544 _previous_versions->append(pv_node);
3545 }
3547 // Since the caller is the VMThread and we are at a safepoint, this
3548 // is a good time to clear out unused references.
3550 RC_TRACE(0x00000400, ("add: previous version length=%d",
3551 _previous_versions->length()));
3553 // Purge previous versions not executing on the stack
3554 purge_previous_versions_internal(this, emcp_method_count);
3556 int obsolete_method_count = old_methods->length() - emcp_method_count;
3558 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3559 _previous_versions->length() > 0) {
3560 // We have a mix of obsolete and EMCP methods so we have to
3561 // clear out any matching EMCP method entries the hard way.
3562 int local_count = 0;
3563 for (int i = 0; i < old_methods->length(); i++) {
3564 if (!emcp_methods->at(i)) {
3565 // only obsolete methods are interesting
3566 Method* old_method = old_methods->at(i);
3567 Symbol* m_name = old_method->name();
3568 Symbol* m_signature = old_method->signature();
3570 // we might not have added the last entry
3571 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3572 // check the previous versions array for non executing obsolete methods
3573 PreviousVersionNode * pv_node = _previous_versions->at(j);
3575 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3576 if (method_refs == NULL) {
3577 // We have run into a PreviousVersion generation where
3578 // all methods were made obsolete during that generation's
3579 // RedefineClasses() operation. At the time of that
3580 // operation, all EMCP methods were flushed so we don't
3581 // have to go back any further.
3582 //
3583 // A NULL method_refs is different than an empty method_refs.
3584 // We cannot infer any optimizations about older generations
3585 // from an empty method_refs for the current generation.
3586 break;
3587 }
3589 for (int k = method_refs->length() - 1; k >= 0; k--) {
3590 Method* method = method_refs->at(k);
3592 if (!method->is_obsolete() &&
3593 method->name() == m_name &&
3594 method->signature() == m_signature) {
3595 // The current RedefineClasses() call has made all EMCP
3596 // versions of this method obsolete so mark it as obsolete
3597 // and remove the reference.
3598 RC_TRACE(0x00000400,
3599 ("add: %s(%s): flush obsolete method @%d in version @%d",
3600 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3602 method->set_is_obsolete();
3603 // Leave obsolete methods on the previous version list to
3604 // clean up later.
3605 break;
3606 }
3607 }
3609 // The previous loop may not find a matching EMCP method, but
3610 // that doesn't mean that we can optimize and not go any
3611 // further back in the PreviousVersion generations. The EMCP
3612 // method for this generation could have already been deleted,
3613 // but there still may be an older EMCP method that has not
3614 // been deleted.
3615 }
3617 if (++local_count >= obsolete_method_count) {
3618 // no more obsolete methods so bail out now
3619 break;
3620 }
3621 }
3622 }
3623 }
3624 } // end add_previous_version()
3627 // Determine if InstanceKlass has a previous version.
3628 bool InstanceKlass::has_previous_version() const {
3629 return (_previous_versions != NULL && _previous_versions->length() > 0);
3630 } // end has_previous_version()
3633 Method* InstanceKlass::method_with_idnum(int idnum) {
3634 Method* m = NULL;
3635 if (idnum < methods()->length()) {
3636 m = methods()->at(idnum);
3637 }
3638 if (m == NULL || m->method_idnum() != idnum) {
3639 for (int index = 0; index < methods()->length(); ++index) {
3640 m = methods()->at(index);
3641 if (m->method_idnum() == idnum) {
3642 return m;
3643 }
3644 }
3645 // None found, return null for the caller to handle.
3646 return NULL;
3647 }
3648 return m;
3649 }
3651 jint InstanceKlass::get_cached_class_file_len() {
3652 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3653 }
3655 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3656 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3657 }
3660 // Construct a PreviousVersionNode entry for the array hung off
3661 // the InstanceKlass.
3662 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3663 GrowableArray<Method*>* prev_EMCP_methods) {
3665 _prev_constant_pool = prev_constant_pool;
3666 _prev_EMCP_methods = prev_EMCP_methods;
3667 }
3670 // Destroy a PreviousVersionNode
3671 PreviousVersionNode::~PreviousVersionNode() {
3672 if (_prev_constant_pool != NULL) {
3673 _prev_constant_pool = NULL;
3674 }
3676 if (_prev_EMCP_methods != NULL) {
3677 delete _prev_EMCP_methods;
3678 }
3679 }
3681 // Construct a helper for walking the previous versions array
3682 PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) {
3683 _thread = thread;
3684 _previous_versions = ik->previous_versions();
3685 _current_index = 0;
3686 _current_p = NULL;
3687 _current_constant_pool_handle = constantPoolHandle(thread, ik->constants());
3688 }
3691 // Return the interesting information for the next previous version
3692 // of the klass. Returns NULL if there are no more previous versions.
3693 PreviousVersionNode* PreviousVersionWalker::next_previous_version() {
3694 if (_previous_versions == NULL) {
3695 // no previous versions so nothing to return
3696 return NULL;
3697 }
3699 _current_p = NULL; // reset to NULL
3700 _current_constant_pool_handle = NULL;
3702 int length = _previous_versions->length();
3704 while (_current_index < length) {
3705 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3707 // Save a handle to the constant pool for this previous version,
3708 // which keeps all the methods from being deallocated.
3709 _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool());
3710 _current_p = pv_node;
3711 return pv_node;
3712 }
3714 return NULL;
3715 } // end next_previous_version()