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