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