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