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 "code/dependencyContext.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "gc/shared/collectedHeap.inline.hpp"
33 #include "gc/shared/specialized_oop_closures.hpp"
34 #include "interpreter/oopMapCache.hpp"
35 #include "interpreter/rewriter.hpp"
36 #include "jvmtifiles/jvmti.h"
37 #include "memory/heapInspection.hpp"
38 #include "memory/iterator.inline.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/oopFactory.hpp"
41 #include "oops/fieldStreams.hpp"
42 #include "oops/instanceClassLoaderKlass.hpp"
43 #include "oops/instanceKlass.inline.hpp"
44 #include "oops/instanceMirrorKlass.hpp"
45 #include "oops/instanceOop.hpp"
46 #include "oops/klass.inline.hpp"
47 #include "oops/method.hpp"
48 #include "oops/oop.inline.hpp"
49 #include "oops/symbol.hpp"
50 #include "prims/jvmtiExport.hpp"
51 #include "prims/jvmtiRedefineClasses.hpp"
52 #include "prims/jvmtiRedefineClassesTrace.hpp"
53 #include "prims/jvmtiThreadState.hpp"
54 #include "prims/methodComparator.hpp"
55 #include "runtime/atomic.inline.hpp"
56 #include "runtime/fieldDescriptor.hpp"
57 #include "runtime/handles.inline.hpp"
58 #include "runtime/javaCalls.hpp"
59 #include "runtime/mutexLocker.hpp"
60 #include "runtime/orderAccess.inline.hpp"
61 #include "runtime/thread.inline.hpp"
62 #include "services/classLoadingService.hpp"
63 #include "services/threadService.hpp"
64 #include "utilities/dtrace.hpp"
65 #include "utilities/macros.hpp"
66 #ifdef COMPILER1
67 #include "c1/c1_Compiler.hpp"
68 #endif
69
70 #ifdef DTRACE_ENABLED
71
72
73 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
74 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
75 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
76 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
77 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
78 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
79 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
80 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
81 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
82 { \
83 char* data = NULL; \
84 int len = 0; \
85 Symbol* name = (clss)->name(); \
86 if (name != NULL) { \
87 data = (char*)name->bytes(); \
88 len = name->utf8_length(); \
89 } \
90 HOTSPOT_CLASS_INITIALIZATION_##type( \
91 data, len, (clss)->class_loader(), thread_type); \
92 }
93
94 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
95 { \
96 char* data = NULL; \
97 int len = 0; \
98 Symbol* name = (clss)->name(); \
99 if (name != NULL) { \
100 data = (char*)name->bytes(); \
101 len = name->utf8_length(); \
102 } \
103 HOTSPOT_CLASS_INITIALIZATION_##type( \
104 data, len, (clss)->class_loader(), thread_type, wait); \
105 }
106
107 #else // ndef DTRACE_ENABLED
108
109 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
110 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
111
112 #endif // ndef DTRACE_ENABLED
113
114 volatile int InstanceKlass::_total_instanceKlass_count = 0;
115
116 InstanceKlass* InstanceKlass::allocate_instance_klass(
117 ClassLoaderData* loader_data,
118 int vtable_len,
119 int itable_len,
120 int static_field_size,
121 int nonstatic_oop_map_size,
122 ReferenceType rt,
123 AccessFlags access_flags,
124 Symbol* name,
125 Klass* super_klass,
126 bool is_anonymous,
127 TRAPS) {
128
129 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
130 access_flags.is_interface(), is_anonymous);
131
132 // Allocation
133 InstanceKlass* ik;
134 if (rt == REF_NONE) {
135 if (name == vmSymbols::java_lang_Class()) {
136 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
137 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
138 access_flags, is_anonymous);
139 } else if (name == vmSymbols::java_lang_ClassLoader() ||
140 (SystemDictionary::ClassLoader_klass_loaded() &&
141 super_klass != NULL &&
142 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
143 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
144 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
145 access_flags, is_anonymous);
146 } else {
147 // normal class
148 ik = new (loader_data, size, THREAD) InstanceKlass(
149 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size,
150 InstanceKlass::_misc_kind_other, rt, access_flags, is_anonymous);
151 }
152 } else {
153 // reference klass
154 ik = new (loader_data, size, THREAD) InstanceRefKlass(
155 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
156 access_flags, is_anonymous);
157 }
158
159 // Check for pending exception before adding to the loader data and incrementing
160 // class count. Can get OOM here.
161 if (HAS_PENDING_EXCEPTION) {
162 return NULL;
163 }
164
165 // Add all classes to our internal class loader list here,
166 // including classes in the bootstrap (NULL) class loader.
167 loader_data->add_class(ik);
168
169 Atomic::inc(&_total_instanceKlass_count);
170 return ik;
171 }
172
173
174 // copy method ordering from resource area to Metaspace
175 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
176 if (m != NULL) {
177 // allocate a new array and copy contents (memcpy?)
178 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
179 for (int i = 0; i < m->length(); i++) {
180 _method_ordering->at_put(i, m->at(i));
181 }
182 } else {
183 _method_ordering = Universe::the_empty_int_array();
184 }
185 }
186
187 // create a new array of vtable_indices for default methods
188 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
189 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
190 assert(default_vtable_indices() == NULL, "only create once");
191 set_default_vtable_indices(vtable_indices);
192 return vtable_indices;
193 }
194
195 InstanceKlass::InstanceKlass(int vtable_len,
196 int itable_len,
197 int static_field_size,
198 int nonstatic_oop_map_size,
199 unsigned kind,
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 set_vtable_length(vtable_len);
208 set_itable_length(itable_len);
209 set_static_field_size(static_field_size);
210 set_nonstatic_oop_map_size(nonstatic_oop_map_size);
211 set_access_flags(access_flags);
212 _misc_flags = 0; // initialize to zero
213 set_kind(kind);
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 _dep_context = DependencyContext::EMPTY;
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 set_jvmti_cached_class_field_map(NULL);
250 set_cached_class_file(NULL);
251 set_initial_method_idnum(0);
252 set_minor_version(0);
253 set_major_version(0);
254 NOT_PRODUCT(_verify_count = 0;)
255
256 // initialize the non-header words to zero
257 intptr_t* p = (intptr_t*)this;
258 for (int index = InstanceKlass::header_size(); index < iksize; index++) {
259 p[index] = NULL_WORD;
260 }
261
262 // Set temporary value until parseClassFile updates it with the real instance
263 // size.
264 set_layout_helper(Klass::instance_layout_helper(0, true));
265 }
266
267
268 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
269 Array<Method*>* methods) {
270 if (methods != NULL && methods != Universe::the_empty_method_array() &&
271 !methods->is_shared()) {
272 for (int i = 0; i < methods->length(); i++) {
273 Method* method = methods->at(i);
274 if (method == NULL) continue; // maybe null if error processing
275 // Only want to delete methods that are not executing for RedefineClasses.
276 // The previous version will point to them so they're not totally dangling
277 assert (!method->on_stack(), "shouldn't be called with methods on stack");
278 MetadataFactory::free_metadata(loader_data, method);
279 }
280 MetadataFactory::free_array<Method*>(loader_data, methods);
281 }
282 }
283
284 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
285 Klass* super_klass,
286 Array<Klass*>* local_interfaces,
287 Array<Klass*>* transitive_interfaces) {
288 // Only deallocate transitive interfaces if not empty, same as super class
289 // or same as local interfaces. See code in parseClassFile.
290 Array<Klass*>* ti = transitive_interfaces;
291 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
292 // check that the interfaces don't come from super class
293 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
294 InstanceKlass::cast(super_klass)->transitive_interfaces();
295 if (ti != sti && ti != NULL && !ti->is_shared()) {
296 MetadataFactory::free_array<Klass*>(loader_data, ti);
297 }
298 }
299
300 // local interfaces can be empty
301 if (local_interfaces != Universe::the_empty_klass_array() &&
302 local_interfaces != NULL && !local_interfaces->is_shared()) {
303 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
304 }
305 }
306
307 // This function deallocates the metadata and C heap pointers that the
308 // InstanceKlass points to.
309 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
310
311 // Orphan the mirror first, CMS thinks it's still live.
312 if (java_mirror() != NULL) {
313 java_lang_Class::set_klass(java_mirror(), NULL);
314 }
315
316 // Need to take this class off the class loader data list.
317 loader_data->remove_class(this);
318
319 // The array_klass for this class is created later, after error handling.
320 // For class redefinition, we keep the original class so this scratch class
321 // doesn't have an array class. Either way, assert that there is nothing
322 // to deallocate.
323 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
324
325 // Release C heap allocated data that this might point to, which includes
326 // reference counting symbol names.
327 release_C_heap_structures();
328
329 deallocate_methods(loader_data, methods());
330 set_methods(NULL);
331
332 if (method_ordering() != NULL &&
333 method_ordering() != Universe::the_empty_int_array() &&
334 !method_ordering()->is_shared()) {
335 MetadataFactory::free_array<int>(loader_data, method_ordering());
336 }
337 set_method_ordering(NULL);
338
339 // default methods can be empty
340 if (default_methods() != NULL &&
341 default_methods() != Universe::the_empty_method_array() &&
342 !default_methods()->is_shared()) {
343 MetadataFactory::free_array<Method*>(loader_data, default_methods());
344 }
345 // Do NOT deallocate the default methods, they are owned by superinterfaces.
346 set_default_methods(NULL);
347
348 // default methods vtable indices can be empty
349 if (default_vtable_indices() != NULL &&
350 !default_vtable_indices()->is_shared()) {
351 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
352 }
353 set_default_vtable_indices(NULL);
354
355
356 // This array is in Klass, but remove it with the InstanceKlass since
357 // this place would be the only caller and it can share memory with transitive
358 // interfaces.
359 if (secondary_supers() != NULL &&
360 secondary_supers() != Universe::the_empty_klass_array() &&
361 secondary_supers() != transitive_interfaces() &&
362 !secondary_supers()->is_shared()) {
363 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
364 }
365 set_secondary_supers(NULL);
366
367 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
368 set_transitive_interfaces(NULL);
369 set_local_interfaces(NULL);
370
371 if (fields() != NULL && !fields()->is_shared()) {
372 MetadataFactory::free_array<jushort>(loader_data, fields());
373 }
374 set_fields(NULL, 0);
375
376 // If a method from a redefined class is using this constant pool, don't
377 // delete it, yet. The new class's previous version will point to this.
378 if (constants() != NULL) {
379 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
380 if (!constants()->is_shared()) {
381 MetadataFactory::free_metadata(loader_data, constants());
382 }
383 // Delete any cached resolution errors for the constant pool
384 SystemDictionary::delete_resolution_error(constants());
385
386 set_constants(NULL);
387 }
388
389 if (inner_classes() != NULL &&
390 inner_classes() != Universe::the_empty_short_array() &&
391 !inner_classes()->is_shared()) {
392 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
393 }
394 set_inner_classes(NULL);
395
396 // We should deallocate the Annotations instance if it's not in shared spaces.
397 if (annotations() != NULL && !annotations()->is_shared()) {
398 MetadataFactory::free_metadata(loader_data, annotations());
399 }
400 set_annotations(NULL);
401 }
402
403 bool InstanceKlass::should_be_initialized() const {
404 return !is_initialized();
405 }
406
407 klassVtable* InstanceKlass::vtable() const {
408 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
409 }
410
411 klassItable* InstanceKlass::itable() const {
412 return new klassItable(instanceKlassHandle(this));
413 }
414
415 void InstanceKlass::eager_initialize(Thread *thread) {
416 if (!EagerInitialization) return;
417
418 if (this->is_not_initialized()) {
419 // abort if the the class has a class initializer
420 if (this->class_initializer() != NULL) return;
421
422 // abort if it is java.lang.Object (initialization is handled in genesis)
423 Klass* super = this->super();
424 if (super == NULL) return;
425
426 // abort if the super class should be initialized
427 if (!InstanceKlass::cast(super)->is_initialized()) return;
428
429 // call body to expose the this pointer
430 instanceKlassHandle this_k(thread, this);
431 eager_initialize_impl(this_k);
432 }
433 }
434
435 // JVMTI spec thinks there are signers and protection domain in the
436 // instanceKlass. These accessors pretend these fields are there.
437 // The hprof specification also thinks these fields are in InstanceKlass.
438 oop InstanceKlass::protection_domain() const {
439 // return the protection_domain from the mirror
440 return java_lang_Class::protection_domain(java_mirror());
441 }
442
443 // To remove these from requires an incompatible change and CCC request.
444 objArrayOop InstanceKlass::signers() const {
445 // return the signers from the mirror
446 return java_lang_Class::signers(java_mirror());
447 }
448
449 oop InstanceKlass::init_lock() const {
450 // return the init lock from the mirror
451 oop lock = java_lang_Class::init_lock(java_mirror());
452 // Prevent reordering with any access of initialization state
453 OrderAccess::loadload();
454 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
455 "only fully initialized state can have a null lock");
456 return lock;
457 }
458
459 // Set the initialization lock to null so the object can be GC'ed. Any racing
460 // threads to get this lock will see a null lock and will not lock.
461 // That's okay because they all check for initialized state after getting
462 // the lock and return.
463 void InstanceKlass::fence_and_clear_init_lock() {
464 // make sure previous stores are all done, notably the init_state.
465 OrderAccess::storestore();
466 java_lang_Class::set_init_lock(java_mirror(), NULL);
467 assert(!is_not_initialized(), "class must be initialized now");
468 }
469
470 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
471 EXCEPTION_MARK;
472 oop init_lock = this_k->init_lock();
473 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
474
475 // abort if someone beat us to the initialization
476 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized()
477
478 ClassState old_state = this_k->init_state();
479 link_class_impl(this_k, true, THREAD);
480 if (HAS_PENDING_EXCEPTION) {
481 CLEAR_PENDING_EXCEPTION;
482 // Abort if linking the class throws an exception.
483
484 // Use a test to avoid redundantly resetting the state if there's
485 // no change. Set_init_state() asserts that state changes make
486 // progress, whereas here we might just be spinning in place.
487 if( old_state != this_k->_init_state )
488 this_k->set_init_state (old_state);
489 } else {
490 // linking successfull, mark class as initialized
491 this_k->set_init_state (fully_initialized);
492 this_k->fence_and_clear_init_lock();
493 // trace
494 if (TraceClassInitialization) {
495 ResourceMark rm(THREAD);
496 tty->print_cr("[Initialized %s without side effects]", this_k->external_name());
497 }
498 }
499 }
500
501
502 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
503 // process. The step comments refers to the procedure described in that section.
504 // Note: implementation moved to static method to expose the this pointer.
505 void InstanceKlass::initialize(TRAPS) {
506 if (this->should_be_initialized()) {
507 HandleMark hm(THREAD);
508 instanceKlassHandle this_k(THREAD, this);
509 initialize_impl(this_k, CHECK);
510 // Note: at this point the class may be initialized
511 // OR it may be in the state of being initialized
512 // in case of recursive initialization!
513 } else {
514 assert(is_initialized(), "sanity check");
515 }
516 }
517
518
519 bool InstanceKlass::verify_code(
520 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
521 // 1) Verify the bytecodes
522 Verifier::Mode mode =
523 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
524 return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD);
525 }
526
527
528 // Used exclusively by the shared spaces dump mechanism to prevent
529 // classes mapped into the shared regions in new VMs from appearing linked.
530
531 void InstanceKlass::unlink_class() {
532 assert(is_linked(), "must be linked");
533 _init_state = loaded;
534 }
535
536 void InstanceKlass::link_class(TRAPS) {
537 assert(is_loaded(), "must be loaded");
538 if (!is_linked()) {
539 HandleMark hm(THREAD);
540 instanceKlassHandle this_k(THREAD, this);
541 link_class_impl(this_k, true, CHECK);
542 }
543 }
544
545 // Called to verify that a class can link during initialization, without
546 // throwing a VerifyError.
547 bool InstanceKlass::link_class_or_fail(TRAPS) {
548 assert(is_loaded(), "must be loaded");
549 if (!is_linked()) {
550 HandleMark hm(THREAD);
551 instanceKlassHandle this_k(THREAD, this);
552 link_class_impl(this_k, false, CHECK_false);
553 }
554 return is_linked();
555 }
556
557 bool InstanceKlass::link_class_impl(
558 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
559 // check for error state
560 if (this_k->is_in_error_state()) {
561 ResourceMark rm(THREAD);
562 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
563 this_k->external_name(), false);
564 }
565 // return if already verified
566 if (this_k->is_linked()) {
567 return true;
568 }
569
570 // Timing
571 // timer handles recursion
572 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
573 JavaThread* jt = (JavaThread*)THREAD;
574
575 // link super class before linking this class
576 instanceKlassHandle super(THREAD, this_k->super());
577 if (super.not_null()) {
578 if (super->is_interface()) { // check if super class is an interface
579 ResourceMark rm(THREAD);
580 Exceptions::fthrow(
581 THREAD_AND_LOCATION,
582 vmSymbols::java_lang_IncompatibleClassChangeError(),
583 "class %s has interface %s as super class",
584 this_k->external_name(),
585 super->external_name()
586 );
587 return false;
588 }
589
590 link_class_impl(super, throw_verifyerror, CHECK_false);
591 }
592
593 // link all interfaces implemented by this class before linking this class
594 Array<Klass*>* interfaces = this_k->local_interfaces();
595 int num_interfaces = interfaces->length();
596 for (int index = 0; index < num_interfaces; index++) {
597 HandleMark hm(THREAD);
598 instanceKlassHandle ih(THREAD, interfaces->at(index));
599 link_class_impl(ih, throw_verifyerror, CHECK_false);
600 }
601
602 // in case the class is linked in the process of linking its superclasses
603 if (this_k->is_linked()) {
604 return true;
605 }
606
607 // trace only the link time for this klass that includes
608 // the verification time
609 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
610 ClassLoader::perf_class_link_selftime(),
611 ClassLoader::perf_classes_linked(),
612 jt->get_thread_stat()->perf_recursion_counts_addr(),
613 jt->get_thread_stat()->perf_timers_addr(),
614 PerfClassTraceTime::CLASS_LINK);
615
616 // verification & rewriting
617 {
618 oop init_lock = this_k->init_lock();
619 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
620 // rewritten will have been set if loader constraint error found
621 // on an earlier link attempt
622 // don't verify or rewrite if already rewritten
623
624 if (!this_k->is_linked()) {
625 if (!this_k->is_rewritten()) {
626 {
627 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
628 if (!verify_ok) {
629 return false;
630 }
631 }
632
633 // Just in case a side-effect of verify linked this class already
634 // (which can sometimes happen since the verifier loads classes
635 // using custom class loaders, which are free to initialize things)
636 if (this_k->is_linked()) {
637 return true;
638 }
639
640 // also sets rewritten
641 this_k->rewrite_class(CHECK_false);
642 }
643
644 // relocate jsrs and link methods after they are all rewritten
645 this_k->link_methods(CHECK_false);
646
647 // Initialize the vtable and interface table after
648 // methods have been rewritten since rewrite may
649 // fabricate new Method*s.
650 // also does loader constraint checking
651 if (!this_k()->is_shared()) {
652 ResourceMark rm(THREAD);
653 this_k->vtable()->initialize_vtable(true, CHECK_false);
654 this_k->itable()->initialize_itable(true, CHECK_false);
655 }
656 #ifdef ASSERT
657 else {
658 ResourceMark rm(THREAD);
659 this_k->vtable()->verify(tty, true);
660 // In case itable verification is ever added.
661 // this_k->itable()->verify(tty, true);
662 }
663 #endif
664 this_k->set_init_state(linked);
665 if (JvmtiExport::should_post_class_prepare()) {
666 Thread *thread = THREAD;
667 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
668 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
669 }
670 }
671 }
672 return true;
673 }
674
675
676 // Rewrite the byte codes of all of the methods of a class.
677 // The rewriter must be called exactly once. Rewriting must happen after
678 // verification but before the first method of the class is executed.
679 void InstanceKlass::rewrite_class(TRAPS) {
680 assert(is_loaded(), "must be loaded");
681 instanceKlassHandle this_k(THREAD, this);
682 if (this_k->is_rewritten()) {
683 assert(this_k()->is_shared(), "rewriting an unshared class?");
684 return;
685 }
686 Rewriter::rewrite(this_k, CHECK);
687 this_k->set_rewritten();
688 }
689
690 // Now relocate and link method entry points after class is rewritten.
691 // This is outside is_rewritten flag. In case of an exception, it can be
692 // executed more than once.
693 void InstanceKlass::link_methods(TRAPS) {
694 int len = methods()->length();
695 for (int i = len-1; i >= 0; i--) {
696 methodHandle m(THREAD, methods()->at(i));
697
698 // Set up method entry points for compiler and interpreter .
699 m->link_method(m, CHECK);
700 }
701 }
702
703 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
704 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) {
705 if (this_k->has_default_methods()) {
706 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
707 Klass* iface = this_k->local_interfaces()->at(i);
708 InstanceKlass* ik = InstanceKlass::cast(iface);
709 if (ik->should_be_initialized()) {
710 if (ik->has_default_methods()) {
711 ik->initialize_super_interfaces(ik, THREAD);
712 }
713 // Only initialize() interfaces that "declare" concrete methods.
714 // has_default_methods drives searching superinterfaces since it
715 // means has_default_methods in its superinterface hierarchy
716 if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) {
717 ik->initialize(THREAD);
718 }
719 if (HAS_PENDING_EXCEPTION) {
720 Handle e(THREAD, PENDING_EXCEPTION);
721 CLEAR_PENDING_EXCEPTION;
722 {
723 EXCEPTION_MARK;
724 // Locks object, set state, and notify all waiting threads
725 this_k->set_initialization_state_and_notify(
726 initialization_error, THREAD);
727
728 // ignore any exception thrown, superclass initialization error is
729 // thrown below
730 CLEAR_PENDING_EXCEPTION;
731 }
732 THROW_OOP(e());
733 }
734 }
735 }
736 }
737 }
738
739 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
740 // Make sure klass is linked (verified) before initialization
741 // A class could already be verified, since it has been reflected upon.
742 this_k->link_class(CHECK);
743
744 DTRACE_CLASSINIT_PROBE(required, this_k(), -1);
745
746 bool wait = false;
747
748 // refer to the JVM book page 47 for description of steps
749 // Step 1
750 {
751 oop init_lock = this_k->init_lock();
752 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
753
754 Thread *self = THREAD; // it's passed the current thread
755
756 // Step 2
757 // If we were to use wait() instead of waitInterruptibly() then
758 // we might end up throwing IE from link/symbol resolution sites
759 // that aren't expected to throw. This would wreak havoc. See 6320309.
760 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
761 wait = true;
762 ol.waitUninterruptibly(CHECK);
763 }
764
765 // Step 3
766 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
767 DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k(), -1,wait);
768 return;
769 }
770
771 // Step 4
772 if (this_k->is_initialized()) {
773 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k(), -1,wait);
774 return;
775 }
776
777 // Step 5
778 if (this_k->is_in_error_state()) {
779 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k(), -1,wait);
780 ResourceMark rm(THREAD);
781 const char* desc = "Could not initialize class ";
782 const char* className = this_k->external_name();
783 size_t msglen = strlen(desc) + strlen(className) + 1;
784 char* message = NEW_RESOURCE_ARRAY(char, msglen);
785 if (NULL == message) {
786 // Out of memory: can't create detailed error message
787 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
788 } else {
789 jio_snprintf(message, msglen, "%s%s", desc, className);
790 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
791 }
792 }
793
794 // Step 6
795 this_k->set_init_state(being_initialized);
796 this_k->set_init_thread(self);
797 }
798
799 // Step 7
800 Klass* super_klass = this_k->super();
801 if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) {
802 super_klass->initialize(THREAD);
803
804 if (HAS_PENDING_EXCEPTION) {
805 Handle e(THREAD, PENDING_EXCEPTION);
806 CLEAR_PENDING_EXCEPTION;
807 {
808 EXCEPTION_MARK;
809 this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
810 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
811 }
812 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k(), -1,wait);
813 THROW_OOP(e());
814 }
815 }
816
817 // If C is an interface that declares a non-abstract, non-static method,
818 // the initialization of a class (not an interface) that implements C directly or
819 // indirectly.
820 // Recursively initialize any superinterfaces that declare default methods
821 // Only need to recurse if has_default_methods which includes declaring and
822 // inheriting default methods
823 if (!this_k->is_interface() && this_k->has_default_methods()) {
824 this_k->initialize_super_interfaces(this_k, CHECK);
825 }
826
827 // Step 8
828 {
829 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
830 JavaThread* jt = (JavaThread*)THREAD;
831 DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k(), -1,wait);
832 // Timer includes any side effects of class initialization (resolution,
833 // etc), but not recursive entry into call_class_initializer().
834 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
835 ClassLoader::perf_class_init_selftime(),
836 ClassLoader::perf_classes_inited(),
837 jt->get_thread_stat()->perf_recursion_counts_addr(),
838 jt->get_thread_stat()->perf_timers_addr(),
839 PerfClassTraceTime::CLASS_CLINIT);
840 this_k->call_class_initializer(THREAD);
841 }
842
843 // Step 9
844 if (!HAS_PENDING_EXCEPTION) {
845 this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
846 { ResourceMark rm(THREAD);
847 debug_only(this_k->vtable()->verify(tty, true);)
848 }
849 }
850 else {
851 // Step 10 and 11
852 Handle e(THREAD, PENDING_EXCEPTION);
853 CLEAR_PENDING_EXCEPTION;
854 // JVMTI has already reported the pending exception
855 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
856 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
857 {
858 EXCEPTION_MARK;
859 this_k->set_initialization_state_and_notify(initialization_error, THREAD);
860 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
861 // JVMTI has already reported the pending exception
862 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
863 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
864 }
865 DTRACE_CLASSINIT_PROBE_WAIT(error, this_k(), -1,wait);
866 if (e->is_a(SystemDictionary::Error_klass())) {
867 THROW_OOP(e());
868 } else {
869 JavaCallArguments args(e);
870 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
871 vmSymbols::throwable_void_signature(),
872 &args);
873 }
874 }
875 DTRACE_CLASSINIT_PROBE_WAIT(end, this_k(), -1,wait);
876 }
877
878
879 // Note: implementation moved to static method to expose the this pointer.
880 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
881 instanceKlassHandle kh(THREAD, this);
882 set_initialization_state_and_notify_impl(kh, state, CHECK);
883 }
884
885 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
886 oop init_lock = this_k->init_lock();
887 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
888 this_k->set_init_state(state);
889 this_k->fence_and_clear_init_lock();
890 ol.notify_all(CHECK);
891 }
892
893 // The embedded _implementor field can only record one implementor.
894 // When there are more than one implementors, the _implementor field
895 // is set to the interface Klass* itself. Following are the possible
896 // values for the _implementor field:
897 // NULL - no implementor
898 // implementor Klass* - one implementor
899 // self - more than one implementor
900 //
901 // The _implementor field only exists for interfaces.
902 void InstanceKlass::add_implementor(Klass* k) {
903 assert(Compile_lock->owned_by_self(), "");
904 assert(is_interface(), "not interface");
905 // Filter out my subinterfaces.
906 // (Note: Interfaces are never on the subklass list.)
907 if (InstanceKlass::cast(k)->is_interface()) return;
908
909 // Filter out subclasses whose supers already implement me.
910 // (Note: CHA must walk subclasses of direct implementors
911 // in order to locate indirect implementors.)
912 Klass* sk = k->super();
913 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
914 // We only need to check one immediate superclass, since the
915 // implements_interface query looks at transitive_interfaces.
916 // Any supers of the super have the same (or fewer) transitive_interfaces.
917 return;
918
919 Klass* ik = implementor();
920 if (ik == NULL) {
921 set_implementor(k);
922 } else if (ik != this) {
923 // There is already an implementor. Use itself as an indicator of
924 // more than one implementors.
925 set_implementor(this);
926 }
927
928 // The implementor also implements the transitive_interfaces
929 for (int index = 0; index < local_interfaces()->length(); index++) {
930 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
931 }
932 }
933
934 void InstanceKlass::init_implementor() {
935 if (is_interface()) {
936 set_implementor(NULL);
937 }
938 }
939
940
941 void InstanceKlass::process_interfaces(Thread *thread) {
942 // link this class into the implementors list of every interface it implements
943 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
944 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
945 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
946 assert(interf->is_interface(), "expected interface");
947 interf->add_implementor(this);
948 }
949 }
950
951 bool InstanceKlass::can_be_primary_super_slow() const {
952 if (is_interface())
953 return false;
954 else
955 return Klass::can_be_primary_super_slow();
956 }
957
958 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
959 // The secondaries are the implemented interfaces.
960 Array<Klass*>* interfaces = transitive_interfaces();
961 int num_secondaries = num_extra_slots + interfaces->length();
962 if (num_secondaries == 0) {
963 // Must share this for correct bootstrapping!
964 set_secondary_supers(Universe::the_empty_klass_array());
965 return NULL;
966 } else if (num_extra_slots == 0) {
967 // The secondary super list is exactly the same as the transitive interfaces.
968 // Redefine classes has to be careful not to delete this!
969 set_secondary_supers(interfaces);
970 return NULL;
971 } else {
972 // Copy transitive interfaces to a temporary growable array to be constructed
973 // into the secondary super list with extra slots.
974 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
975 for (int i = 0; i < interfaces->length(); i++) {
976 secondaries->push(interfaces->at(i));
977 }
978 return secondaries;
979 }
980 }
981
982 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
983 if (k->is_interface()) {
984 return implements_interface(k);
985 } else {
986 return Klass::compute_is_subtype_of(k);
987 }
988 }
989
990 bool InstanceKlass::implements_interface(Klass* k) const {
991 if (this == k) return true;
992 assert(k->is_interface(), "should be an interface class");
993 for (int i = 0; i < transitive_interfaces()->length(); i++) {
994 if (transitive_interfaces()->at(i) == k) {
995 return true;
996 }
997 }
998 return false;
999 }
1000
1001 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1002 // Verify direct super interface
1003 if (this == k) return true;
1004 assert(k->is_interface(), "should be an interface class");
1005 for (int i = 0; i < local_interfaces()->length(); i++) {
1006 if (local_interfaces()->at(i) == k) {
1007 return true;
1008 }
1009 }
1010 return false;
1011 }
1012
1013 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1014 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1015 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1016 report_java_out_of_memory("Requested array size exceeds VM limit");
1017 JvmtiExport::post_array_size_exhausted();
1018 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1019 }
1020 int size = objArrayOopDesc::object_size(length);
1021 Klass* ak = array_klass(n, CHECK_NULL);
1022 KlassHandle h_ak (THREAD, ak);
1023 objArrayOop o =
1024 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1025 return o;
1026 }
1027
1028 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1029 if (TraceFinalizerRegistration) {
1030 tty->print("Registered ");
1031 i->print_value_on(tty);
1032 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1033 }
1034 instanceHandle h_i(THREAD, i);
1035 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1036 JavaValue result(T_VOID);
1037 JavaCallArguments args(h_i);
1038 methodHandle mh (THREAD, Universe::finalizer_register_method());
1039 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1040 return h_i();
1041 }
1042
1043 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1044 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1045 int size = size_helper(); // Query before forming handle.
1046
1047 KlassHandle h_k(THREAD, this);
1048
1049 instanceOop i;
1050
1051 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1052 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1053 i = register_finalizer(i, CHECK_NULL);
1054 }
1055 return i;
1056 }
1057
1058 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1059 if (is_interface() || is_abstract()) {
1060 ResourceMark rm(THREAD);
1061 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1062 : vmSymbols::java_lang_InstantiationException(), external_name());
1063 }
1064 if (this == SystemDictionary::Class_klass()) {
1065 ResourceMark rm(THREAD);
1066 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1067 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1068 }
1069 }
1070
1071 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1072 instanceKlassHandle this_k(THREAD, this);
1073 return array_klass_impl(this_k, or_null, n, THREAD);
1074 }
1075
1076 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1077 if (this_k->array_klasses() == NULL) {
1078 if (or_null) return NULL;
1079
1080 ResourceMark rm;
1081 JavaThread *jt = (JavaThread *)THREAD;
1082 {
1083 // Atomic creation of array_klasses
1084 MutexLocker mc(Compile_lock, THREAD); // for vtables
1085 MutexLocker ma(MultiArray_lock, THREAD);
1086
1087 // Check if update has already taken place
1088 if (this_k->array_klasses() == NULL) {
1089 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1090 this_k->set_array_klasses(k);
1091 }
1092 }
1093 }
1094 // _this will always be set at this point
1095 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1096 if (or_null) {
1097 return oak->array_klass_or_null(n);
1098 }
1099 return oak->array_klass(n, THREAD);
1100 }
1101
1102 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1103 return array_klass_impl(or_null, 1, THREAD);
1104 }
1105
1106 void InstanceKlass::call_class_initializer(TRAPS) {
1107 instanceKlassHandle ik (THREAD, this);
1108 call_class_initializer_impl(ik, THREAD);
1109 }
1110
1111 static int call_class_initializer_impl_counter = 0; // for debugging
1112
1113 Method* InstanceKlass::class_initializer() {
1114 Method* clinit = find_method(
1115 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1116 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1117 return clinit;
1118 }
1119 return NULL;
1120 }
1121
1122 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1123 if (ReplayCompiles &&
1124 (ReplaySuppressInitializers == 1 ||
1125 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1126 // Hide the existence of the initializer for the purpose of replaying the compile
1127 return;
1128 }
1129
1130 methodHandle h_method(THREAD, this_k->class_initializer());
1131 assert(!this_k->is_initialized(), "we cannot initialize twice");
1132 if (TraceClassInitialization) {
1133 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1134 this_k->name()->print_value();
1135 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k()));
1136 }
1137 if (h_method() != NULL) {
1138 JavaCallArguments args; // No arguments
1139 JavaValue result(T_VOID);
1140 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1141 }
1142 }
1143
1144
1145 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1146 InterpreterOopMap* entry_for) {
1147 // Dirty read, then double-check under a lock.
1148 if (_oop_map_cache == NULL) {
1149 // Otherwise, allocate a new one.
1150 MutexLocker x(OopMapCacheAlloc_lock);
1151 // First time use. Allocate a cache in C heap
1152 if (_oop_map_cache == NULL) {
1153 // Release stores from OopMapCache constructor before assignment
1154 // to _oop_map_cache. C++ compilers on ppc do not emit the
1155 // required memory barrier only because of the volatile
1156 // qualifier of _oop_map_cache.
1157 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1158 }
1159 }
1160 // _oop_map_cache is constant after init; lookup below does is own locking.
1161 _oop_map_cache->lookup(method, bci, entry_for);
1162 }
1163
1164
1165 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1166 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1167 Symbol* f_name = fs.name();
1168 Symbol* f_sig = fs.signature();
1169 if (f_name == name && f_sig == sig) {
1170 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1171 return true;
1172 }
1173 }
1174 return false;
1175 }
1176
1177
1178 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1179 const int n = local_interfaces()->length();
1180 for (int i = 0; i < n; i++) {
1181 Klass* intf1 = local_interfaces()->at(i);
1182 assert(intf1->is_interface(), "just checking type");
1183 // search for field in current interface
1184 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1185 assert(fd->is_static(), "interface field must be static");
1186 return intf1;
1187 }
1188 // search for field in direct superinterfaces
1189 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1190 if (intf2 != NULL) return intf2;
1191 }
1192 // otherwise field lookup fails
1193 return NULL;
1194 }
1195
1196
1197 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1198 // search order according to newest JVM spec (5.4.3.2, p.167).
1199 // 1) search for field in current klass
1200 if (find_local_field(name, sig, fd)) {
1201 return const_cast<InstanceKlass*>(this);
1202 }
1203 // 2) search for field recursively in direct superinterfaces
1204 { Klass* intf = find_interface_field(name, sig, fd);
1205 if (intf != NULL) return intf;
1206 }
1207 // 3) apply field lookup recursively if superclass exists
1208 { Klass* supr = super();
1209 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1210 }
1211 // 4) otherwise field lookup fails
1212 return NULL;
1213 }
1214
1215
1216 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1217 // search order according to newest JVM spec (5.4.3.2, p.167).
1218 // 1) search for field in current klass
1219 if (find_local_field(name, sig, fd)) {
1220 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1221 }
1222 // 2) search for field recursively in direct superinterfaces
1223 if (is_static) {
1224 Klass* intf = find_interface_field(name, sig, fd);
1225 if (intf != NULL) return intf;
1226 }
1227 // 3) apply field lookup recursively if superclass exists
1228 { Klass* supr = super();
1229 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1230 }
1231 // 4) otherwise field lookup fails
1232 return NULL;
1233 }
1234
1235
1236 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1237 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1238 if (fs.offset() == offset) {
1239 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1240 if (fd->is_static() == is_static) return true;
1241 }
1242 }
1243 return false;
1244 }
1245
1246
1247 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1248 Klass* klass = const_cast<InstanceKlass*>(this);
1249 while (klass != NULL) {
1250 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1251 return true;
1252 }
1253 klass = klass->super();
1254 }
1255 return false;
1256 }
1257
1258
1259 void InstanceKlass::methods_do(void f(Method* method)) {
1260 // Methods aren't stable until they are loaded. This can be read outside
1261 // a lock through the ClassLoaderData for profiling
1262 if (!is_loaded()) {
1263 return;
1264 }
1265
1266 int len = methods()->length();
1267 for (int index = 0; index < len; index++) {
1268 Method* m = methods()->at(index);
1269 assert(m->is_method(), "must be method");
1270 f(m);
1271 }
1272 }
1273
1274
1275 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1276 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1277 if (fs.access_flags().is_static()) {
1278 fieldDescriptor& fd = fs.field_descriptor();
1279 cl->do_field(&fd);
1280 }
1281 }
1282 }
1283
1284
1285 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1286 instanceKlassHandle h_this(THREAD, this);
1287 do_local_static_fields_impl(h_this, f, mirror, CHECK);
1288 }
1289
1290
1291 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1292 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1293 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1294 if (fs.access_flags().is_static()) {
1295 fieldDescriptor& fd = fs.field_descriptor();
1296 f(&fd, mirror, CHECK);
1297 }
1298 }
1299 }
1300
1301
1302 static int compare_fields_by_offset(int* a, int* b) {
1303 return a[0] - b[0];
1304 }
1305
1306 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1307 InstanceKlass* super = superklass();
1308 if (super != NULL) {
1309 super->do_nonstatic_fields(cl);
1310 }
1311 fieldDescriptor fd;
1312 int length = java_fields_count();
1313 // In DebugInfo nonstatic fields are sorted by offset.
1314 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1315 int j = 0;
1316 for (int i = 0; i < length; i += 1) {
1317 fd.reinitialize(this, i);
1318 if (!fd.is_static()) {
1319 fields_sorted[j + 0] = fd.offset();
1320 fields_sorted[j + 1] = i;
1321 j += 2;
1322 }
1323 }
1324 if (j > 0) {
1325 length = j;
1326 // _sort_Fn is defined in growableArray.hpp.
1327 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1328 for (int i = 0; i < length; i += 2) {
1329 fd.reinitialize(this, fields_sorted[i + 1]);
1330 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1331 cl->do_field(&fd);
1332 }
1333 }
1334 FREE_C_HEAP_ARRAY(int, fields_sorted);
1335 }
1336
1337
1338 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1339 if (array_klasses() != NULL)
1340 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1341 }
1342
1343 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1344 if (array_klasses() != NULL)
1345 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1346 }
1347
1348 #ifdef ASSERT
1349 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1350 int len = methods->length();
1351 for (int index = 0; index < len; index++) {
1352 Method* m = methods->at(index);
1353 assert(m->is_method(), "must be method");
1354 if (m->signature() == signature && m->name() == name) {
1355 return index;
1356 }
1357 }
1358 return -1;
1359 }
1360 #endif
1361
1362 static int binary_search(Array<Method*>* methods, Symbol* name) {
1363 int len = methods->length();
1364 // methods are sorted, so do binary search
1365 int l = 0;
1366 int h = len - 1;
1367 while (l <= h) {
1368 int mid = (l + h) >> 1;
1369 Method* m = methods->at(mid);
1370 assert(m->is_method(), "must be method");
1371 int res = m->name()->fast_compare(name);
1372 if (res == 0) {
1373 return mid;
1374 } else if (res < 0) {
1375 l = mid + 1;
1376 } else {
1377 h = mid - 1;
1378 }
1379 }
1380 return -1;
1381 }
1382
1383 // find_method looks up the name/signature in the local methods array
1384 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1385 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1386 }
1387
1388 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature,
1389 OverpassLookupMode overpass_mode,
1390 StaticLookupMode static_mode,
1391 PrivateLookupMode private_mode) const {
1392 return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode, private_mode);
1393 }
1394
1395 // find_instance_method looks up the name/signature in the local methods array
1396 // and skips over static methods
1397 Method* InstanceKlass::find_instance_method(
1398 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1399 Method* meth = InstanceKlass::find_method_impl(methods, name, signature,
1400 find_overpass, skip_static, find_private);
1401 assert(((meth == NULL) || !meth->is_static()), "find_instance_method should have skipped statics");
1402 return meth;
1403 }
1404
1405 // find_instance_method looks up the name/signature in the local methods array
1406 // and skips over static methods
1407 Method* InstanceKlass::find_instance_method(Symbol* name, Symbol* signature) {
1408 return InstanceKlass::find_instance_method(methods(), name, signature);
1409 }
1410
1411 // Find looks up the name/signature in the local methods array
1412 // and filters on the overpass, static and private flags
1413 // This returns the first one found
1414 // note that the local methods array can have up to one overpass, one static
1415 // and one instance (private or not) with the same name/signature
1416 Method* InstanceKlass::find_local_method(Symbol* name, Symbol* signature,
1417 OverpassLookupMode overpass_mode,
1418 StaticLookupMode static_mode,
1419 PrivateLookupMode private_mode) const {
1420 return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode, private_mode);
1421 }
1422
1423 // Find looks up the name/signature in the local methods array
1424 // and filters on the overpass, static and private flags
1425 // This returns the first one found
1426 // note that the local methods array can have up to one overpass, one static
1427 // and one instance (private or not) with the same name/signature
1428 Method* InstanceKlass::find_local_method(Array<Method*>* methods,
1429 Symbol* name, Symbol* signature,
1430 OverpassLookupMode overpass_mode,
1431 StaticLookupMode static_mode,
1432 PrivateLookupMode private_mode) {
1433 return InstanceKlass::find_method_impl(methods, name, signature, overpass_mode, static_mode, private_mode);
1434 }
1435
1436
1437 // find_method looks up the name/signature in the local methods array
1438 Method* InstanceKlass::find_method(
1439 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1440 return InstanceKlass::find_method_impl(methods, name, signature, find_overpass, find_static, find_private);
1441 }
1442
1443 Method* InstanceKlass::find_method_impl(
1444 Array<Method*>* methods, Symbol* name, Symbol* signature,
1445 OverpassLookupMode overpass_mode, StaticLookupMode static_mode,
1446 PrivateLookupMode private_mode) {
1447 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1448 return hit >= 0 ? methods->at(hit): NULL;
1449 }
1450
1451 bool InstanceKlass::method_matches(Method* m, Symbol* signature, bool skipping_overpass, bool skipping_static, bool skipping_private) {
1452 return ((m->signature() == signature) &&
1453 (!skipping_overpass || !m->is_overpass()) &&
1454 (!skipping_static || !m->is_static()) &&
1455 (!skipping_private || !m->is_private()));
1456 }
1457
1458 // Used directly for default_methods to find the index into the
1459 // default_vtable_indices, and indirectly by find_method
1460 // find_method_index looks in the local methods array to return the index
1461 // of the matching name/signature. If, overpass methods are being ignored,
1462 // the search continues to find a potential non-overpass match. This capability
1463 // is important during method resolution to prefer a static method, for example,
1464 // over an overpass method.
1465 // There is the possibility in any _method's array to have the same name/signature
1466 // for a static method, an overpass method and a local instance method
1467 // To correctly catch a given method, the search criteria may need
1468 // to explicitly skip the other two. For local instance methods, it
1469 // is often necessary to skip private methods
1470 int InstanceKlass::find_method_index(
1471 Array<Method*>* methods, Symbol* name, Symbol* signature,
1472 OverpassLookupMode overpass_mode, StaticLookupMode static_mode,
1473 PrivateLookupMode private_mode) {
1474 bool skipping_overpass = (overpass_mode == skip_overpass);
1475 bool skipping_static = (static_mode == skip_static);
1476 bool skipping_private = (private_mode == skip_private);
1477 int hit = binary_search(methods, name);
1478 if (hit != -1) {
1479 Method* m = methods->at(hit);
1480
1481 // Do linear search to find matching signature. First, quick check
1482 // for common case, ignoring overpasses if requested.
1483 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return hit;
1484
1485 // search downwards through overloaded methods
1486 int i;
1487 for (i = hit - 1; i >= 0; --i) {
1488 Method* m = methods->at(i);
1489 assert(m->is_method(), "must be method");
1490 if (m->name() != name) break;
1491 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return i;
1492 }
1493 // search upwards
1494 for (i = hit + 1; i < methods->length(); ++i) {
1495 Method* m = methods->at(i);
1496 assert(m->is_method(), "must be method");
1497 if (m->name() != name) break;
1498 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return i;
1499 }
1500 // not found
1501 #ifdef ASSERT
1502 int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : linear_search(methods, name, signature);
1503 assert(index == -1, "binary search should have found entry %d", index);
1504 #endif
1505 }
1506 return -1;
1507 }
1508 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1509 return find_method_by_name(methods(), name, end);
1510 }
1511
1512 int InstanceKlass::find_method_by_name(
1513 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1514 assert(end_ptr != NULL, "just checking");
1515 int start = binary_search(methods, name);
1516 int end = start + 1;
1517 if (start != -1) {
1518 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1519 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1520 *end_ptr = end;
1521 return start;
1522 }
1523 return -1;
1524 }
1525
1526 // uncached_lookup_method searches both the local class methods array and all
1527 // superclasses methods arrays, skipping any overpass methods in superclasses.
1528 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, OverpassLookupMode overpass_mode) const {
1529 OverpassLookupMode overpass_local_mode = overpass_mode;
1530 Klass* klass = const_cast<InstanceKlass*>(this);
1531 while (klass != NULL) {
1532 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, overpass_local_mode, find_static, find_private);
1533 if (method != NULL) {
1534 return method;
1535 }
1536 klass = klass->super();
1537 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1538 }
1539 return NULL;
1540 }
1541
1542 #ifdef ASSERT
1543 // search through class hierarchy and return true if this class or
1544 // one of the superclasses was redefined
1545 bool InstanceKlass::has_redefined_this_or_super() {
1546 Klass* klass = this;
1547 while (klass != NULL) {
1548 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1549 return true;
1550 }
1551 klass = klass->super();
1552 }
1553 return false;
1554 }
1555 #endif
1556
1557 // lookup a method in the default methods list then in all transitive interfaces
1558 // Do NOT return private or static methods
1559 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1560 Symbol* signature) const {
1561 Method* m = NULL;
1562 if (default_methods() != NULL) {
1563 m = find_method(default_methods(), name, signature);
1564 }
1565 // Look up interfaces
1566 if (m == NULL) {
1567 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1568 }
1569 return m;
1570 }
1571
1572 // lookup a method in all the interfaces that this class implements
1573 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1574 // They should only be found in the initial InterfaceMethodRef
1575 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1576 Symbol* signature,
1577 DefaultsLookupMode defaults_mode) const {
1578 Array<Klass*>* all_ifs = transitive_interfaces();
1579 int num_ifs = all_ifs->length();
1580 InstanceKlass *ik = NULL;
1581 for (int i = 0; i < num_ifs; i++) {
1582 ik = InstanceKlass::cast(all_ifs->at(i));
1583 Method* m = ik->lookup_method(name, signature);
1584 if (m != NULL && m->is_public() && !m->is_static() &&
1585 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1586 return m;
1587 }
1588 }
1589 return NULL;
1590 }
1591
1592 /* jni_id_for_impl for jfieldIds only */
1593 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1594 MutexLocker ml(JfieldIdCreation_lock);
1595 // Retry lookup after we got the lock
1596 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1597 if (probe == NULL) {
1598 // Slow case, allocate new static field identifier
1599 probe = new JNIid(this_k(), offset, this_k->jni_ids());
1600 this_k->set_jni_ids(probe);
1601 }
1602 return probe;
1603 }
1604
1605
1606 /* jni_id_for for jfieldIds only */
1607 JNIid* InstanceKlass::jni_id_for(int offset) {
1608 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1609 if (probe == NULL) {
1610 probe = jni_id_for_impl(this, offset);
1611 }
1612 return probe;
1613 }
1614
1615 u2 InstanceKlass::enclosing_method_data(int offset) {
1616 Array<jushort>* inner_class_list = inner_classes();
1617 if (inner_class_list == NULL) {
1618 return 0;
1619 }
1620 int length = inner_class_list->length();
1621 if (length % inner_class_next_offset == 0) {
1622 return 0;
1623 } else {
1624 int index = length - enclosing_method_attribute_size;
1625 assert(offset < enclosing_method_attribute_size, "invalid offset");
1626 return inner_class_list->at(index + offset);
1627 }
1628 }
1629
1630 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1631 u2 method_index) {
1632 Array<jushort>* inner_class_list = inner_classes();
1633 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1634 int length = inner_class_list->length();
1635 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1636 int index = length - enclosing_method_attribute_size;
1637 inner_class_list->at_put(
1638 index + enclosing_method_class_index_offset, class_index);
1639 inner_class_list->at_put(
1640 index + enclosing_method_method_index_offset, method_index);
1641 }
1642 }
1643
1644 // Lookup or create a jmethodID.
1645 // This code is called by the VMThread and JavaThreads so the
1646 // locking has to be done very carefully to avoid deadlocks
1647 // and/or other cache consistency problems.
1648 //
1649 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, const methodHandle& method_h) {
1650 size_t idnum = (size_t)method_h->method_idnum();
1651 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1652 size_t length = 0;
1653 jmethodID id = NULL;
1654
1655 // We use a double-check locking idiom here because this cache is
1656 // performance sensitive. In the normal system, this cache only
1657 // transitions from NULL to non-NULL which is safe because we use
1658 // release_set_methods_jmethod_ids() to advertise the new cache.
1659 // A partially constructed cache should never be seen by a racing
1660 // thread. We also use release_store_ptr() to save a new jmethodID
1661 // in the cache so a partially constructed jmethodID should never be
1662 // seen either. Cache reads of existing jmethodIDs proceed without a
1663 // lock, but cache writes of a new jmethodID requires uniqueness and
1664 // creation of the cache itself requires no leaks so a lock is
1665 // generally acquired in those two cases.
1666 //
1667 // If the RedefineClasses() API has been used, then this cache can
1668 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1669 // Cache creation requires no leaks and we require safety between all
1670 // cache accesses and freeing of the old cache so a lock is generally
1671 // acquired when the RedefineClasses() API has been used.
1672
1673 if (jmeths != NULL) {
1674 // the cache already exists
1675 if (!ik_h->idnum_can_increment()) {
1676 // the cache can't grow so we can just get the current values
1677 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1678 } else {
1679 // cache can grow so we have to be more careful
1680 if (Threads::number_of_threads() == 0 ||
1681 SafepointSynchronize::is_at_safepoint()) {
1682 // we're single threaded or at a safepoint - no locking needed
1683 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1684 } else {
1685 MutexLocker ml(JmethodIdCreation_lock);
1686 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1687 }
1688 }
1689 }
1690 // implied else:
1691 // we need to allocate a cache so default length and id values are good
1692
1693 if (jmeths == NULL || // no cache yet
1694 length <= idnum || // cache is too short
1695 id == NULL) { // cache doesn't contain entry
1696
1697 // This function can be called by the VMThread so we have to do all
1698 // things that might block on a safepoint before grabbing the lock.
1699 // Otherwise, we can deadlock with the VMThread or have a cache
1700 // consistency issue. These vars keep track of what we might have
1701 // to free after the lock is dropped.
1702 jmethodID to_dealloc_id = NULL;
1703 jmethodID* to_dealloc_jmeths = NULL;
1704
1705 // may not allocate new_jmeths or use it if we allocate it
1706 jmethodID* new_jmeths = NULL;
1707 if (length <= idnum) {
1708 // allocate a new cache that might be used
1709 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1710 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1711 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1712 // cache size is stored in element[0], other elements offset by one
1713 new_jmeths[0] = (jmethodID)size;
1714 }
1715
1716 // allocate a new jmethodID that might be used
1717 jmethodID new_id = NULL;
1718 if (method_h->is_old() && !method_h->is_obsolete()) {
1719 // The method passed in is old (but not obsolete), we need to use the current version
1720 Method* current_method = ik_h->method_with_idnum((int)idnum);
1721 assert(current_method != NULL, "old and but not obsolete, so should exist");
1722 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1723 } else {
1724 // It is the current version of the method or an obsolete method,
1725 // use the version passed in
1726 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1727 }
1728
1729 if (Threads::number_of_threads() == 0 ||
1730 SafepointSynchronize::is_at_safepoint()) {
1731 // we're single threaded or at a safepoint - no locking needed
1732 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1733 &to_dealloc_id, &to_dealloc_jmeths);
1734 } else {
1735 MutexLocker ml(JmethodIdCreation_lock);
1736 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1737 &to_dealloc_id, &to_dealloc_jmeths);
1738 }
1739
1740 // The lock has been dropped so we can free resources.
1741 // Free up either the old cache or the new cache if we allocated one.
1742 if (to_dealloc_jmeths != NULL) {
1743 FreeHeap(to_dealloc_jmeths);
1744 }
1745 // free up the new ID since it wasn't needed
1746 if (to_dealloc_id != NULL) {
1747 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1748 }
1749 }
1750 return id;
1751 }
1752
1753 // Figure out how many jmethodIDs haven't been allocated, and make
1754 // sure space for them is pre-allocated. This makes getting all
1755 // method ids much, much faster with classes with more than 8
1756 // methods, and has a *substantial* effect on performance with jvmti
1757 // code that loads all jmethodIDs for all classes.
1758 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1759 int new_jmeths = 0;
1760 int length = methods()->length();
1761 for (int index = start_offset; index < length; index++) {
1762 Method* m = methods()->at(index);
1763 jmethodID id = m->find_jmethod_id_or_null();
1764 if (id == NULL) {
1765 new_jmeths++;
1766 }
1767 }
1768 if (new_jmeths != 0) {
1769 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1770 }
1771 }
1772
1773 // Common code to fetch the jmethodID from the cache or update the
1774 // cache with the new jmethodID. This function should never do anything
1775 // that causes the caller to go to a safepoint or we can deadlock with
1776 // the VMThread or have cache consistency issues.
1777 //
1778 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1779 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1780 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1781 jmethodID** to_dealloc_jmeths_p) {
1782 assert(new_id != NULL, "sanity check");
1783 assert(to_dealloc_id_p != NULL, "sanity check");
1784 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1785 assert(Threads::number_of_threads() == 0 ||
1786 SafepointSynchronize::is_at_safepoint() ||
1787 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1788
1789 // reacquire the cache - we are locked, single threaded or at a safepoint
1790 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1791 jmethodID id = NULL;
1792 size_t length = 0;
1793
1794 if (jmeths == NULL || // no cache yet
1795 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1796 if (jmeths != NULL) {
1797 // copy any existing entries from the old cache
1798 for (size_t index = 0; index < length; index++) {
1799 new_jmeths[index+1] = jmeths[index+1];
1800 }
1801 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1802 }
1803 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1804 } else {
1805 // fetch jmethodID (if any) from the existing cache
1806 id = jmeths[idnum+1];
1807 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1808 }
1809 if (id == NULL) {
1810 // No matching jmethodID in the existing cache or we have a new
1811 // cache or we just grew the cache. This cache write is done here
1812 // by the first thread to win the foot race because a jmethodID
1813 // needs to be unique once it is generally available.
1814 id = new_id;
1815
1816 // The jmethodID cache can be read while unlocked so we have to
1817 // make sure the new jmethodID is complete before installing it
1818 // in the cache.
1819 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1820 } else {
1821 *to_dealloc_id_p = new_id; // save new id for later delete
1822 }
1823 return id;
1824 }
1825
1826
1827 // Common code to get the jmethodID cache length and the jmethodID
1828 // value at index idnum if there is one.
1829 //
1830 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1831 size_t idnum, size_t *length_p, jmethodID* id_p) {
1832 assert(cache != NULL, "sanity check");
1833 assert(length_p != NULL, "sanity check");
1834 assert(id_p != NULL, "sanity check");
1835
1836 // cache size is stored in element[0], other elements offset by one
1837 *length_p = (size_t)cache[0];
1838 if (*length_p <= idnum) { // cache is too short
1839 *id_p = NULL;
1840 } else {
1841 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1842 }
1843 }
1844
1845
1846 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1847 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1848 size_t idnum = (size_t)method->method_idnum();
1849 jmethodID* jmeths = methods_jmethod_ids_acquire();
1850 size_t length; // length assigned as debugging crumb
1851 jmethodID id = NULL;
1852 if (jmeths != NULL && // If there is a cache
1853 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1854 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1855 }
1856 return id;
1857 }
1858
1859 inline DependencyContext InstanceKlass::dependencies() {
1860 DependencyContext dep_context(&_dep_context);
1861 return dep_context;
1862 }
1863
1864 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1865 return dependencies().mark_dependent_nmethods(changes);
1866 }
1867
1868 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1869 dependencies().add_dependent_nmethod(nm);
1870 }
1871
1872 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1873 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1874 }
1875
1876 #ifndef PRODUCT
1877 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1878 dependencies().print_dependent_nmethods(verbose);
1879 }
1880
1881 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1882 return dependencies().is_dependent_nmethod(nm);
1883 }
1884 #endif //PRODUCT
1885
1886 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
1887 clean_implementors_list(is_alive);
1888 clean_method_data(is_alive);
1889
1890 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
1891 DependencyContext dep_context(&_dep_context);
1892 dep_context.expunge_stale_entries();
1893 }
1894
1895 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
1896 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
1897 if (is_interface()) {
1898 if (ClassUnloading) {
1899 Klass* impl = implementor();
1900 if (impl != NULL) {
1901 if (!impl->is_loader_alive(is_alive)) {
1902 // remove this guy
1903 Klass** klass = adr_implementor();
1904 assert(klass != NULL, "null klass");
1905 if (klass != NULL) {
1906 *klass = NULL;
1907 }
1908 }
1909 }
1910 }
1911 }
1912 }
1913
1914 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
1915 for (int m = 0; m < methods()->length(); m++) {
1916 MethodData* mdo = methods()->at(m)->method_data();
1917 if (mdo != NULL) {
1918 mdo->clean_method_data(is_alive);
1919 }
1920 }
1921 }
1922
1923
1924 static void remove_unshareable_in_class(Klass* k) {
1925 // remove klass's unshareable info
1926 k->remove_unshareable_info();
1927 }
1928
1929 void InstanceKlass::remove_unshareable_info() {
1930 Klass::remove_unshareable_info();
1931 // Unlink the class
1932 if (is_linked()) {
1933 unlink_class();
1934 }
1935 init_implementor();
1936
1937 constants()->remove_unshareable_info();
1938
1939 assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable");
1940
1941 for (int i = 0; i < methods()->length(); i++) {
1942 Method* m = methods()->at(i);
1943 m->remove_unshareable_info();
1944 }
1945
1946 // do array classes also.
1947 array_klasses_do(remove_unshareable_in_class);
1948 }
1949
1950 static void restore_unshareable_in_class(Klass* k, TRAPS) {
1951 // Array classes have null protection domain.
1952 // --> see ArrayKlass::complete_create_array_klass()
1953 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
1954 }
1955
1956 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
1957 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
1958 instanceKlassHandle ik(THREAD, this);
1959
1960 Array<Method*>* methods = ik->methods();
1961 int num_methods = methods->length();
1962 for (int index2 = 0; index2 < num_methods; ++index2) {
1963 methodHandle m(THREAD, methods->at(index2));
1964 m->restore_unshareable_info(CHECK);
1965 }
1966 if (JvmtiExport::has_redefined_a_class()) {
1967 // Reinitialize vtable because RedefineClasses may have changed some
1968 // entries in this vtable for super classes so the CDS vtable might
1969 // point to old or obsolete entries. RedefineClasses doesn't fix up
1970 // vtables in the shared system dictionary, only the main one.
1971 // It also redefines the itable too so fix that too.
1972 ResourceMark rm(THREAD);
1973 ik->vtable()->initialize_vtable(false, CHECK);
1974 ik->itable()->initialize_itable(false, CHECK);
1975 }
1976
1977 // restore constant pool resolved references
1978 ik->constants()->restore_unshareable_info(CHECK);
1979
1980 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
1981 }
1982
1983 // returns true IFF is_in_error_state() has been changed as a result of this call.
1984 bool InstanceKlass::check_sharing_error_state() {
1985 assert(DumpSharedSpaces, "should only be called during dumping");
1986 bool old_state = is_in_error_state();
1987
1988 if (!is_in_error_state()) {
1989 bool bad = false;
1990 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
1991 if (sup->is_in_error_state()) {
1992 bad = true;
1993 break;
1994 }
1995 }
1996 if (!bad) {
1997 Array<Klass*>* interfaces = transitive_interfaces();
1998 for (int i = 0; i < interfaces->length(); i++) {
1999 Klass* iface = interfaces->at(i);
2000 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2001 bad = true;
2002 break;
2003 }
2004 }
2005 }
2006
2007 if (bad) {
2008 set_in_error_state();
2009 }
2010 }
2011
2012 return (old_state != is_in_error_state());
2013 }
2014
2015 static void clear_all_breakpoints(Method* m) {
2016 m->clear_all_breakpoints();
2017 }
2018
2019
2020 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2021 // notify the debugger
2022 if (JvmtiExport::should_post_class_unload()) {
2023 JvmtiExport::post_class_unload(ik);
2024 }
2025
2026 // notify ClassLoadingService of class unload
2027 ClassLoadingService::notify_class_unloaded(ik);
2028 }
2029
2030 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2031 // Clean up C heap
2032 ik->release_C_heap_structures();
2033 ik->constants()->release_C_heap_structures();
2034 }
2035
2036 void InstanceKlass::release_C_heap_structures() {
2037
2038 // Can't release the constant pool here because the constant pool can be
2039 // deallocated separately from the InstanceKlass for default methods and
2040 // redefine classes.
2041
2042 // Deallocate oop map cache
2043 if (_oop_map_cache != NULL) {
2044 delete _oop_map_cache;
2045 _oop_map_cache = NULL;
2046 }
2047
2048 // Deallocate JNI identifiers for jfieldIDs
2049 JNIid::deallocate(jni_ids());
2050 set_jni_ids(NULL);
2051
2052 jmethodID* jmeths = methods_jmethod_ids_acquire();
2053 if (jmeths != (jmethodID*)NULL) {
2054 release_set_methods_jmethod_ids(NULL);
2055 FreeHeap(jmeths);
2056 }
2057
2058 // Deallocate MemberNameTable
2059 {
2060 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2061 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2062 MemberNameTable* mnt = member_names();
2063 if (mnt != NULL) {
2064 delete mnt;
2065 set_member_names(NULL);
2066 }
2067 }
2068
2069 // Release dependencies.
2070 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2071 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2072 // context can contain live dependencies, since there's a race between nmethod &
2073 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2074 // dependencies aren't removed from the context associated with the class (see
2075 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2076 // live dependencies pointing to unloaded nmethods and causes a crash in
2077 // DC::remove_all_dependents() when it touches unloaded nmethod.
2078 dependencies().wipe();
2079
2080 // Deallocate breakpoint records
2081 if (breakpoints() != 0x0) {
2082 methods_do(clear_all_breakpoints);
2083 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2084 }
2085
2086 // deallocate the cached class file
2087 if (_cached_class_file != NULL) {
2088 os::free(_cached_class_file);
2089 _cached_class_file = NULL;
2090 }
2091
2092 // Decrement symbol reference counts associated with the unloaded class.
2093 if (_name != NULL) _name->decrement_refcount();
2094 // unreference array name derived from this class name (arrays of an unloaded
2095 // class can't be referenced anymore).
2096 if (_array_name != NULL) _array_name->decrement_refcount();
2097 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2098
2099 assert(_total_instanceKlass_count >= 1, "Sanity check");
2100 Atomic::dec(&_total_instanceKlass_count);
2101 }
2102
2103 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2104 if (array == NULL) {
2105 _source_debug_extension = NULL;
2106 } else {
2107 // Adding one to the attribute length in order to store a null terminator
2108 // character could cause an overflow because the attribute length is
2109 // already coded with an u4 in the classfile, but in practice, it's
2110 // unlikely to happen.
2111 assert((length+1) > length, "Overflow checking");
2112 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2113 for (int i = 0; i < length; i++) {
2114 sde[i] = array[i];
2115 }
2116 sde[length] = '\0';
2117 _source_debug_extension = sde;
2118 }
2119 }
2120
2121 address InstanceKlass::static_field_addr(int offset) {
2122 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2123 }
2124
2125
2126 const char* InstanceKlass::signature_name() const {
2127 int hash_len = 0;
2128 char hash_buf[40];
2129
2130 // If this is an anonymous class, append a hash to make the name unique
2131 if (is_anonymous()) {
2132 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2133 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2134 hash_len = (int)strlen(hash_buf);
2135 }
2136
2137 // Get the internal name as a c string
2138 const char* src = (const char*) (name()->as_C_string());
2139 const int src_length = (int)strlen(src);
2140
2141 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2142
2143 // Add L as type indicator
2144 int dest_index = 0;
2145 dest[dest_index++] = 'L';
2146
2147 // Add the actual class name
2148 for (int src_index = 0; src_index < src_length; ) {
2149 dest[dest_index++] = src[src_index++];
2150 }
2151
2152 // If we have a hash, append it
2153 for (int hash_index = 0; hash_index < hash_len; ) {
2154 dest[dest_index++] = hash_buf[hash_index++];
2155 }
2156
2157 // Add the semicolon and the NULL
2158 dest[dest_index++] = ';';
2159 dest[dest_index] = '\0';
2160 return dest;
2161 }
2162
2163 // different verisons of is_same_class_package
2164 bool InstanceKlass::is_same_class_package(Klass* class2) {
2165 if (class2->is_objArray_klass()) {
2166 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2167 }
2168 oop classloader2 = class2->class_loader();
2169 Symbol* classname2 = class2->name();
2170
2171 return InstanceKlass::is_same_class_package(class_loader(), name(),
2172 classloader2, classname2);
2173 }
2174
2175 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2176 return InstanceKlass::is_same_class_package(class_loader(), name(),
2177 classloader2, classname2);
2178 }
2179
2180 // return true if two classes are in the same package, classloader
2181 // and classname information is enough to determine a class's package
2182 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2183 oop class_loader2, Symbol* class_name2) {
2184 if (class_loader1 != class_loader2) {
2185 return false;
2186 } else if (class_name1 == class_name2) {
2187 return true; // skip painful bytewise comparison
2188 } else {
2189 ResourceMark rm;
2190
2191 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2192 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2193 // Otherwise, we just compare jbyte values between the strings.
2194 const jbyte *name1 = class_name1->base();
2195 const jbyte *name2 = class_name2->base();
2196
2197 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2198 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2199
2200 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2201 // One of the two doesn't have a package. Only return true
2202 // if the other one also doesn't have a package.
2203 return last_slash1 == last_slash2;
2204 } else {
2205 // Skip over '['s
2206 if (*name1 == '[') {
2207 do {
2208 name1++;
2209 } while (*name1 == '[');
2210 if (*name1 != 'L') {
2211 // Something is terribly wrong. Shouldn't be here.
2212 return false;
2213 }
2214 }
2215 if (*name2 == '[') {
2216 do {
2217 name2++;
2218 } while (*name2 == '[');
2219 if (*name2 != 'L') {
2220 // Something is terribly wrong. Shouldn't be here.
2221 return false;
2222 }
2223 }
2224
2225 // Check that package part is identical
2226 int length1 = last_slash1 - name1;
2227 int length2 = last_slash2 - name2;
2228
2229 return UTF8::equal(name1, length1, name2, length2);
2230 }
2231 }
2232 }
2233
2234 // Returns true iff super_method can be overridden by a method in targetclassname
2235 // See JSL 3rd edition 8.4.6.1
2236 // Assumes name-signature match
2237 // "this" is InstanceKlass of super_method which must exist
2238 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2239 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2240 // Private methods can not be overridden
2241 if (super_method->is_private()) {
2242 return false;
2243 }
2244 // If super method is accessible, then override
2245 if ((super_method->is_protected()) ||
2246 (super_method->is_public())) {
2247 return true;
2248 }
2249 // Package-private methods are not inherited outside of package
2250 assert(super_method->is_package_private(), "must be package private");
2251 return(is_same_class_package(targetclassloader(), targetclassname));
2252 }
2253
2254 /* defined for now in jvm.cpp, for historical reasons *--
2255 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2256 Symbol*& simple_name_result, TRAPS) {
2257 ...
2258 }
2259 */
2260
2261 // tell if two classes have the same enclosing class (at package level)
2262 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2263 Klass* class2_oop, TRAPS) {
2264 if (class2_oop == class1()) return true;
2265 if (!class2_oop->is_instance_klass()) return false;
2266 instanceKlassHandle class2(THREAD, class2_oop);
2267
2268 // must be in same package before we try anything else
2269 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2270 return false;
2271
2272 // As long as there is an outer1.getEnclosingClass,
2273 // shift the search outward.
2274 instanceKlassHandle outer1 = class1;
2275 for (;;) {
2276 // As we walk along, look for equalities between outer1 and class2.
2277 // Eventually, the walks will terminate as outer1 stops
2278 // at the top-level class around the original class.
2279 bool ignore_inner_is_member;
2280 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2281 CHECK_false);
2282 if (next == NULL) break;
2283 if (next == class2()) return true;
2284 outer1 = instanceKlassHandle(THREAD, next);
2285 }
2286
2287 // Now do the same for class2.
2288 instanceKlassHandle outer2 = class2;
2289 for (;;) {
2290 bool ignore_inner_is_member;
2291 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2292 CHECK_false);
2293 if (next == NULL) break;
2294 // Might as well check the new outer against all available values.
2295 if (next == class1()) return true;
2296 if (next == outer1()) return true;
2297 outer2 = instanceKlassHandle(THREAD, next);
2298 }
2299
2300 // If by this point we have not found an equality between the
2301 // two classes, we know they are in separate package members.
2302 return false;
2303 }
2304
2305 bool InstanceKlass::find_inner_classes_attr(instanceKlassHandle k, int* ooff, int* noff, TRAPS) {
2306 constantPoolHandle i_cp(THREAD, k->constants());
2307 for (InnerClassesIterator iter(k); !iter.done(); iter.next()) {
2308 int ioff = iter.inner_class_info_index();
2309 if (ioff != 0) {
2310 // Check to see if the name matches the class we're looking for
2311 // before attempting to find the class.
2312 if (i_cp->klass_name_at_matches(k, ioff)) {
2313 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2314 if (k() == inner_klass) {
2315 *ooff = iter.outer_class_info_index();
2316 *noff = iter.inner_name_index();
2317 return true;
2318 }
2319 }
2320 }
2321 }
2322 return false;
2323 }
2324
2325 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle k, bool* inner_is_member, TRAPS) {
2326 instanceKlassHandle outer_klass;
2327 *inner_is_member = false;
2328 int ooff = 0, noff = 0;
2329 if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) {
2330 constantPoolHandle i_cp(THREAD, k->constants());
2331 if (ooff != 0) {
2332 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2333 outer_klass = instanceKlassHandle(THREAD, ok);
2334 *inner_is_member = true;
2335 }
2336 if (outer_klass.is_null()) {
2337 // It may be anonymous; try for that.
2338 int encl_method_class_idx = k->enclosing_method_class_index();
2339 if (encl_method_class_idx != 0) {
2340 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2341 outer_klass = instanceKlassHandle(THREAD, ok);
2342 *inner_is_member = false;
2343 }
2344 }
2345 }
2346
2347 // If no inner class attribute found for this class.
2348 if (outer_klass.is_null()) return NULL;
2349
2350 // Throws an exception if outer klass has not declared k as an inner klass
2351 // We need evidence that each klass knows about the other, or else
2352 // the system could allow a spoof of an inner class to gain access rights.
2353 Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL);
2354 return outer_klass();
2355 }
2356
2357 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2358 jint access = access_flags().as_int();
2359
2360 // But check if it happens to be member class.
2361 instanceKlassHandle ik(THREAD, this);
2362 InnerClassesIterator iter(ik);
2363 for (; !iter.done(); iter.next()) {
2364 int ioff = iter.inner_class_info_index();
2365 // Inner class attribute can be zero, skip it.
2366 // Strange but true: JVM spec. allows null inner class refs.
2367 if (ioff == 0) continue;
2368
2369 // only look at classes that are already loaded
2370 // since we are looking for the flags for our self.
2371 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2372 if ((ik->name() == inner_name)) {
2373 // This is really a member class.
2374 access = iter.inner_access_flags();
2375 break;
2376 }
2377 }
2378 // Remember to strip ACC_SUPER bit
2379 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2380 }
2381
2382 jint InstanceKlass::jvmti_class_status() const {
2383 jint result = 0;
2384
2385 if (is_linked()) {
2386 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2387 }
2388
2389 if (is_initialized()) {
2390 assert(is_linked(), "Class status is not consistent");
2391 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2392 }
2393 if (is_in_error_state()) {
2394 result |= JVMTI_CLASS_STATUS_ERROR;
2395 }
2396 return result;
2397 }
2398
2399 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2400 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2401 int method_table_offset_in_words = ioe->offset()/wordSize;
2402 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2403 / itableOffsetEntry::size();
2404
2405 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2406 // If the interface isn't implemented by the receiver class,
2407 // the VM should throw IncompatibleClassChangeError.
2408 if (cnt >= nof_interfaces) {
2409 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2410 }
2411
2412 Klass* ik = ioe->interface_klass();
2413 if (ik == holder) break;
2414 }
2415
2416 itableMethodEntry* ime = ioe->first_method_entry(this);
2417 Method* m = ime[index].method();
2418 if (m == NULL) {
2419 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2420 }
2421 return m;
2422 }
2423
2424
2425 #if INCLUDE_JVMTI
2426 // update default_methods for redefineclasses for methods that are
2427 // not yet in the vtable due to concurrent subclass define and superinterface
2428 // redefinition
2429 // Note: those in the vtable, should have been updated via adjust_method_entries
2430 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2431 // search the default_methods for uses of either obsolete or EMCP methods
2432 if (default_methods() != NULL) {
2433 for (int index = 0; index < default_methods()->length(); index ++) {
2434 Method* old_method = default_methods()->at(index);
2435 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2436 continue; // skip uninteresting entries
2437 }
2438 assert(!old_method->is_deleted(), "default methods may not be deleted");
2439
2440 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2441
2442 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2443 assert(old_method != new_method, "sanity check");
2444
2445 default_methods()->at_put(index, new_method);
2446 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2447 if (!(*trace_name_printed)) {
2448 // RC_TRACE_MESG macro has an embedded ResourceMark
2449 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2450 external_name(),
2451 old_method->method_holder()->external_name()));
2452 *trace_name_printed = true;
2453 }
2454 RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2455 new_method->name()->as_C_string(),
2456 new_method->signature()->as_C_string()));
2457 }
2458 }
2459 }
2460 }
2461 #endif // INCLUDE_JVMTI
2462
2463 // On-stack replacement stuff
2464 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2465 // only one compilation can be active
2466 {
2467 // This is a short non-blocking critical region, so the no safepoint check is ok.
2468 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2469 assert(n->is_osr_method(), "wrong kind of nmethod");
2470 n->set_osr_link(osr_nmethods_head());
2471 set_osr_nmethods_head(n);
2472 // Raise the highest osr level if necessary
2473 if (TieredCompilation) {
2474 Method* m = n->method();
2475 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2476 }
2477 }
2478
2479 // Get rid of the osr methods for the same bci that have lower levels.
2480 if (TieredCompilation) {
2481 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2482 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2483 if (inv != NULL && inv->is_in_use()) {
2484 inv->make_not_entrant();
2485 }
2486 }
2487 }
2488 }
2489
2490
2491 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2492 // This is a short non-blocking critical region, so the no safepoint check is ok.
2493 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2494 assert(n->is_osr_method(), "wrong kind of nmethod");
2495 nmethod* last = NULL;
2496 nmethod* cur = osr_nmethods_head();
2497 int max_level = CompLevel_none; // Find the max comp level excluding n
2498 Method* m = n->method();
2499 // Search for match
2500 while(cur != NULL && cur != n) {
2501 if (TieredCompilation && m == cur->method()) {
2502 // Find max level before n
2503 max_level = MAX2(max_level, cur->comp_level());
2504 }
2505 last = cur;
2506 cur = cur->osr_link();
2507 }
2508 nmethod* next = NULL;
2509 if (cur == n) {
2510 next = cur->osr_link();
2511 if (last == NULL) {
2512 // Remove first element
2513 set_osr_nmethods_head(next);
2514 } else {
2515 last->set_osr_link(next);
2516 }
2517 }
2518 n->set_osr_link(NULL);
2519 if (TieredCompilation) {
2520 cur = next;
2521 while (cur != NULL) {
2522 // Find max level after n
2523 if (m == cur->method()) {
2524 max_level = MAX2(max_level, cur->comp_level());
2525 }
2526 cur = cur->osr_link();
2527 }
2528 m->set_highest_osr_comp_level(max_level);
2529 }
2530 }
2531
2532 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2533 // This is a short non-blocking critical region, so the no safepoint check is ok.
2534 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2535 nmethod* osr = osr_nmethods_head();
2536 int found = 0;
2537 while (osr != NULL) {
2538 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2539 if (osr->method() == m) {
2540 osr->mark_for_deoptimization();
2541 found++;
2542 }
2543 osr = osr->osr_link();
2544 }
2545 return found;
2546 }
2547
2548 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2549 // This is a short non-blocking critical region, so the no safepoint check is ok.
2550 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2551 nmethod* osr = osr_nmethods_head();
2552 nmethod* best = NULL;
2553 while (osr != NULL) {
2554 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2555 // There can be a time when a c1 osr method exists but we are waiting
2556 // for a c2 version. When c2 completes its osr nmethod we will trash
2557 // the c1 version and only be able to find the c2 version. However
2558 // while we overflow in the c1 code at back branches we don't want to
2559 // try and switch to the same code as we are already running
2560
2561 if (osr->method() == m &&
2562 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2563 if (match_level) {
2564 if (osr->comp_level() == comp_level) {
2565 // Found a match - return it.
2566 return osr;
2567 }
2568 } else {
2569 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2570 if (osr->comp_level() == CompLevel_highest_tier) {
2571 // Found the best possible - return it.
2572 return osr;
2573 }
2574 best = osr;
2575 }
2576 }
2577 }
2578 osr = osr->osr_link();
2579 }
2580 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2581 return best;
2582 }
2583 return NULL;
2584 }
2585
2586 bool InstanceKlass::add_member_name(Handle mem_name) {
2587 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2588 MutexLocker ml(MemberNameTable_lock);
2589 DEBUG_ONLY(No_Safepoint_Verifier nsv);
2590
2591 // Check if method has been redefined while taking out MemberNameTable_lock, if so
2592 // return false. We cannot cache obsolete methods. They will crash when the function
2593 // is called!
2594 Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
2595 if (method->is_obsolete()) {
2596 return false;
2597 } else if (method->is_old()) {
2598 // Replace method with redefined version
2599 java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
2600 }
2601
2602 if (_member_names == NULL) {
2603 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2604 }
2605 _member_names->add_member_name(mem_name_wref);
2606 return true;
2607 }
2608
2609 // -----------------------------------------------------------------------------------------------------
2610 // Printing
2611
2612 #ifndef PRODUCT
2613
2614 #define BULLET " - "
2615
2616 static const char* state_names[] = {
2617 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2618 };
2619
2620 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2621 for (int i = 0; i < len; i++) {
2622 intptr_t e = start[i];
2623 st->print("%d : " INTPTR_FORMAT, i, e);
2624 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2625 st->print(" ");
2626 ((Metadata*)e)->print_value_on(st);
2627 }
2628 st->cr();
2629 }
2630 }
2631
2632 void InstanceKlass::print_on(outputStream* st) const {
2633 assert(is_klass(), "must be klass");
2634 Klass::print_on(st);
2635
2636 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2637 st->print(BULLET"klass size: %d", size()); st->cr();
2638 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2639 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2640 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2641 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2642 st->print(BULLET"sub: ");
2643 Klass* sub = subklass();
2644 int n;
2645 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2646 if (n < MaxSubklassPrintSize) {
2647 sub->print_value_on(st);
2648 st->print(" ");
2649 }
2650 }
2651 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2652 st->cr();
2653
2654 if (is_interface()) {
2655 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2656 if (nof_implementors() == 1) {
2657 st->print_cr(BULLET"implementor: ");
2658 st->print(" ");
2659 implementor()->print_value_on(st);
2660 st->cr();
2661 }
2662 }
2663
2664 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2665 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2666 if (Verbose || WizardMode) {
2667 Array<Method*>* method_array = methods();
2668 for (int i = 0; i < method_array->length(); i++) {
2669 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2670 }
2671 }
2672 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2673 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
2674 if (Verbose && default_methods() != NULL) {
2675 Array<Method*>* method_array = default_methods();
2676 for (int i = 0; i < method_array->length(); i++) {
2677 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2678 }
2679 }
2680 if (default_vtable_indices() != NULL) {
2681 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
2682 }
2683 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2684 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2685 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2686 if (class_loader_data() != NULL) {
2687 st->print(BULLET"class loader data: ");
2688 class_loader_data()->print_value_on(st);
2689 st->cr();
2690 }
2691 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2692 if (source_file_name() != NULL) {
2693 st->print(BULLET"source file: ");
2694 source_file_name()->print_value_on(st);
2695 st->cr();
2696 }
2697 if (source_debug_extension() != NULL) {
2698 st->print(BULLET"source debug extension: ");
2699 st->print("%s", source_debug_extension());
2700 st->cr();
2701 }
2702 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
2703 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
2704 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
2705 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
2706 {
2707 bool have_pv = false;
2708 // previous versions are linked together through the InstanceKlass
2709 for (InstanceKlass* pv_node = _previous_versions;
2710 pv_node != NULL;
2711 pv_node = pv_node->previous_versions()) {
2712 if (!have_pv)
2713 st->print(BULLET"previous version: ");
2714 have_pv = true;
2715 pv_node->constants()->print_value_on(st);
2716 }
2717 if (have_pv) st->cr();
2718 }
2719
2720 if (generic_signature() != NULL) {
2721 st->print(BULLET"generic signature: ");
2722 generic_signature()->print_value_on(st);
2723 st->cr();
2724 }
2725 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2726 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2727 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2728 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
2729 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2730 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
2731 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2732 FieldPrinter print_static_field(st);
2733 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2734 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2735 FieldPrinter print_nonstatic_field(st);
2736 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2737 ik->do_nonstatic_fields(&print_nonstatic_field);
2738
2739 st->print(BULLET"non-static oop maps: ");
2740 OopMapBlock* map = start_of_nonstatic_oop_maps();
2741 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2742 while (map < end_map) {
2743 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2744 map++;
2745 }
2746 st->cr();
2747 }
2748
2749 #endif //PRODUCT
2750
2751 void InstanceKlass::print_value_on(outputStream* st) const {
2752 assert(is_klass(), "must be klass");
2753 if (Verbose || WizardMode) access_flags().print_on(st);
2754 name()->print_value_on(st);
2755 }
2756
2757 #ifndef PRODUCT
2758
2759 void FieldPrinter::do_field(fieldDescriptor* fd) {
2760 _st->print(BULLET);
2761 if (_obj == NULL) {
2762 fd->print_on(_st);
2763 _st->cr();
2764 } else {
2765 fd->print_on_for(_st, _obj);
2766 _st->cr();
2767 }
2768 }
2769
2770
2771 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2772 Klass::oop_print_on(obj, st);
2773
2774 if (this == SystemDictionary::String_klass()) {
2775 typeArrayOop value = java_lang_String::value(obj);
2776 juint length = java_lang_String::length(obj);
2777 if (value != NULL &&
2778 value->is_typeArray() &&
2779 length <= (juint) value->length()) {
2780 st->print(BULLET"string: ");
2781 java_lang_String::print(obj, st);
2782 st->cr();
2783 if (!WizardMode) return; // that is enough
2784 }
2785 }
2786
2787 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2788 FieldPrinter print_field(st, obj);
2789 do_nonstatic_fields(&print_field);
2790
2791 if (this == SystemDictionary::Class_klass()) {
2792 st->print(BULLET"signature: ");
2793 java_lang_Class::print_signature(obj, st);
2794 st->cr();
2795 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2796 st->print(BULLET"fake entry for mirror: ");
2797 mirrored_klass->print_value_on_maybe_null(st);
2798 st->cr();
2799 Klass* array_klass = java_lang_Class::array_klass(obj);
2800 st->print(BULLET"fake entry for array: ");
2801 array_klass->print_value_on_maybe_null(st);
2802 st->cr();
2803 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2804 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2805 Klass* real_klass = java_lang_Class::as_Klass(obj);
2806 if (real_klass != NULL && real_klass->is_instance_klass()) {
2807 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2808 }
2809 } else if (this == SystemDictionary::MethodType_klass()) {
2810 st->print(BULLET"signature: ");
2811 java_lang_invoke_MethodType::print_signature(obj, st);
2812 st->cr();
2813 }
2814 }
2815
2816 #endif //PRODUCT
2817
2818 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2819 st->print("a ");
2820 name()->print_value_on(st);
2821 obj->print_address_on(st);
2822 if (this == SystemDictionary::String_klass()
2823 && java_lang_String::value(obj) != NULL) {
2824 ResourceMark rm;
2825 int len = java_lang_String::length(obj);
2826 int plen = (len < 24 ? len : 12);
2827 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2828 st->print(" = \"%s\"", str);
2829 if (len > plen)
2830 st->print("...[%d]", len);
2831 } else if (this == SystemDictionary::Class_klass()) {
2832 Klass* k = java_lang_Class::as_Klass(obj);
2833 st->print(" = ");
2834 if (k != NULL) {
2835 k->print_value_on(st);
2836 } else {
2837 const char* tname = type2name(java_lang_Class::primitive_type(obj));
2838 st->print("%s", tname ? tname : "type?");
2839 }
2840 } else if (this == SystemDictionary::MethodType_klass()) {
2841 st->print(" = ");
2842 java_lang_invoke_MethodType::print_signature(obj, st);
2843 } else if (java_lang_boxing_object::is_instance(obj)) {
2844 st->print(" = ");
2845 java_lang_boxing_object::print(obj, st);
2846 } else if (this == SystemDictionary::LambdaForm_klass()) {
2847 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
2848 if (vmentry != NULL) {
2849 st->print(" => ");
2850 vmentry->print_value_on(st);
2851 }
2852 } else if (this == SystemDictionary::MemberName_klass()) {
2853 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
2854 if (vmtarget != NULL) {
2855 st->print(" = ");
2856 vmtarget->print_value_on(st);
2857 } else {
2858 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
2859 st->print(".");
2860 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
2861 }
2862 }
2863 }
2864
2865 const char* InstanceKlass::internal_name() const {
2866 return external_name();
2867 }
2868
2869 #if INCLUDE_SERVICES
2870 // Size Statistics
2871 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
2872 Klass::collect_statistics(sz);
2873
2874 sz->_inst_size = HeapWordSize * size_helper();
2875 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
2876 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
2877 sz->_nonstatic_oopmap_bytes = HeapWordSize *
2878 ((is_interface() || is_anonymous()) ?
2879 align_object_offset(nonstatic_oop_map_size()) :
2880 nonstatic_oop_map_size());
2881
2882 int n = 0;
2883 n += (sz->_methods_array_bytes = sz->count_array(methods()));
2884 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
2885 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
2886 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
2887 n += (sz->_fields_bytes = sz->count_array(fields()));
2888 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
2889 sz->_ro_bytes += n;
2890
2891 const ConstantPool* cp = constants();
2892 if (cp) {
2893 cp->collect_statistics(sz);
2894 }
2895
2896 const Annotations* anno = annotations();
2897 if (anno) {
2898 anno->collect_statistics(sz);
2899 }
2900
2901 const Array<Method*>* methods_array = methods();
2902 if (methods()) {
2903 for (int i = 0; i < methods_array->length(); i++) {
2904 Method* method = methods_array->at(i);
2905 if (method) {
2906 sz->_method_count ++;
2907 method->collect_statistics(sz);
2908 }
2909 }
2910 }
2911 }
2912 #endif // INCLUDE_SERVICES
2913
2914 // Verification
2915
2916 class VerifyFieldClosure: public OopClosure {
2917 protected:
2918 template <class T> void do_oop_work(T* p) {
2919 oop obj = oopDesc::load_decode_heap_oop(p);
2920 if (!obj->is_oop_or_null()) {
2921 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
2922 Universe::print();
2923 guarantee(false, "boom");
2924 }
2925 }
2926 public:
2927 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
2928 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2929 };
2930
2931 void InstanceKlass::verify_on(outputStream* st) {
2932 #ifndef PRODUCT
2933 // Avoid redundant verifies, this really should be in product.
2934 if (_verify_count == Universe::verify_count()) return;
2935 _verify_count = Universe::verify_count();
2936 #endif
2937
2938 // Verify Klass
2939 Klass::verify_on(st);
2940
2941 // Verify that klass is present in ClassLoaderData
2942 guarantee(class_loader_data()->contains_klass(this),
2943 "this class isn't found in class loader data");
2944
2945 // Verify vtables
2946 if (is_linked()) {
2947 ResourceMark rm;
2948 // $$$ This used to be done only for m/s collections. Doing it
2949 // always seemed a valid generalization. (DLD -- 6/00)
2950 vtable()->verify(st);
2951 }
2952
2953 // Verify first subklass
2954 if (subklass() != NULL) {
2955 guarantee(subklass()->is_klass(), "should be klass");
2956 }
2957
2958 // Verify siblings
2959 Klass* super = this->super();
2960 Klass* sib = next_sibling();
2961 if (sib != NULL) {
2962 if (sib == this) {
2963 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
2964 }
2965
2966 guarantee(sib->is_klass(), "should be klass");
2967 guarantee(sib->super() == super, "siblings should have same superklass");
2968 }
2969
2970 // Verify implementor fields
2971 Klass* im = implementor();
2972 if (im != NULL) {
2973 guarantee(is_interface(), "only interfaces should have implementor set");
2974 guarantee(im->is_klass(), "should be klass");
2975 guarantee(!im->is_interface() || im == this,
2976 "implementors cannot be interfaces");
2977 }
2978
2979 // Verify local interfaces
2980 if (local_interfaces()) {
2981 Array<Klass*>* local_interfaces = this->local_interfaces();
2982 for (int j = 0; j < local_interfaces->length(); j++) {
2983 Klass* e = local_interfaces->at(j);
2984 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
2985 }
2986 }
2987
2988 // Verify transitive interfaces
2989 if (transitive_interfaces() != NULL) {
2990 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
2991 for (int j = 0; j < transitive_interfaces->length(); j++) {
2992 Klass* e = transitive_interfaces->at(j);
2993 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
2994 }
2995 }
2996
2997 // Verify methods
2998 if (methods() != NULL) {
2999 Array<Method*>* methods = this->methods();
3000 for (int j = 0; j < methods->length(); j++) {
3001 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3002 }
3003 for (int j = 0; j < methods->length() - 1; j++) {
3004 Method* m1 = methods->at(j);
3005 Method* m2 = methods->at(j + 1);
3006 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3007 }
3008 }
3009
3010 // Verify method ordering
3011 if (method_ordering() != NULL) {
3012 Array<int>* method_ordering = this->method_ordering();
3013 int length = method_ordering->length();
3014 if (JvmtiExport::can_maintain_original_method_order() ||
3015 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3016 guarantee(length == methods()->length(), "invalid method ordering length");
3017 jlong sum = 0;
3018 for (int j = 0; j < length; j++) {
3019 int original_index = method_ordering->at(j);
3020 guarantee(original_index >= 0, "invalid method ordering index");
3021 guarantee(original_index < length, "invalid method ordering index");
3022 sum += original_index;
3023 }
3024 // Verify sum of indices 0,1,...,length-1
3025 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3026 } else {
3027 guarantee(length == 0, "invalid method ordering length");
3028 }
3029 }
3030
3031 // Verify default methods
3032 if (default_methods() != NULL) {
3033 Array<Method*>* methods = this->default_methods();
3034 for (int j = 0; j < methods->length(); j++) {
3035 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3036 }
3037 for (int j = 0; j < methods->length() - 1; j++) {
3038 Method* m1 = methods->at(j);
3039 Method* m2 = methods->at(j + 1);
3040 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3041 }
3042 }
3043
3044 // Verify JNI static field identifiers
3045 if (jni_ids() != NULL) {
3046 jni_ids()->verify(this);
3047 }
3048
3049 // Verify other fields
3050 if (array_klasses() != NULL) {
3051 guarantee(array_klasses()->is_klass(), "should be klass");
3052 }
3053 if (constants() != NULL) {
3054 guarantee(constants()->is_constantPool(), "should be constant pool");
3055 }
3056 const Klass* host = host_klass();
3057 if (host != NULL) {
3058 guarantee(host->is_klass(), "should be klass");
3059 }
3060 }
3061
3062 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3063 Klass::oop_verify_on(obj, st);
3064 VerifyFieldClosure blk;
3065 obj->oop_iterate_no_header(&blk);
3066 }
3067
3068
3069 // JNIid class for jfieldIDs only
3070 // Note to reviewers:
3071 // These JNI functions are just moved over to column 1 and not changed
3072 // in the compressed oops workspace.
3073 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3074 _holder = holder;
3075 _offset = offset;
3076 _next = next;
3077 debug_only(_is_static_field_id = false;)
3078 }
3079
3080
3081 JNIid* JNIid::find(int offset) {
3082 JNIid* current = this;
3083 while (current != NULL) {
3084 if (current->offset() == offset) return current;
3085 current = current->next();
3086 }
3087 return NULL;
3088 }
3089
3090 void JNIid::deallocate(JNIid* current) {
3091 while (current != NULL) {
3092 JNIid* next = current->next();
3093 delete current;
3094 current = next;
3095 }
3096 }
3097
3098
3099 void JNIid::verify(Klass* holder) {
3100 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3101 int end_field_offset;
3102 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3103
3104 JNIid* current = this;
3105 while (current != NULL) {
3106 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3107 #ifdef ASSERT
3108 int o = current->offset();
3109 if (current->is_static_field_id()) {
3110 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3111 }
3112 #endif
3113 current = current->next();
3114 }
3115 }
3116
3117
3118 #ifdef ASSERT
3119 void InstanceKlass::set_init_state(ClassState state) {
3120 bool good_state = is_shared() ? (_init_state <= state)
3121 : (_init_state < state);
3122 assert(good_state || state == allocated, "illegal state transition");
3123 _init_state = (u1)state;
3124 }
3125 #endif
3126
3127
3128
3129 // RedefineClasses() support for previous versions:
3130 int InstanceKlass::_previous_version_count = 0;
3131
3132 // Purge previous versions before adding new previous versions of the class.
3133 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3134 if (ik->previous_versions() != NULL) {
3135 // This klass has previous versions so see what we can cleanup
3136 // while it is safe to do so.
3137
3138 int deleted_count = 0; // leave debugging breadcrumbs
3139 int live_count = 0;
3140 ClassLoaderData* loader_data = ik->class_loader_data();
3141 assert(loader_data != NULL, "should never be null");
3142
3143 // RC_TRACE macro has an embedded ResourceMark
3144 RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name()));
3145
3146 // previous versions are linked together through the InstanceKlass
3147 InstanceKlass* pv_node = ik->previous_versions();
3148 InstanceKlass* last = ik;
3149 int version = 0;
3150
3151 // check the previous versions list
3152 for (; pv_node != NULL; ) {
3153
3154 ConstantPool* pvcp = pv_node->constants();
3155 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3156
3157 if (!pvcp->on_stack()) {
3158 // If the constant pool isn't on stack, none of the methods
3159 // are executing. Unlink this previous_version.
3160 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3161 // so will be deallocated during the next phase of class unloading.
3162 RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead",
3163 p2i(pv_node)));
3164 // For debugging purposes.
3165 pv_node->set_is_scratch_class();
3166 pv_node->class_loader_data()->add_to_deallocate_list(pv_node);
3167 pv_node = pv_node->previous_versions();
3168 last->link_previous_versions(pv_node);
3169 deleted_count++;
3170 version++;
3171 continue;
3172 } else {
3173 RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive",
3174 p2i(pv_node)));
3175 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3176 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3177 live_count++;
3178 }
3179
3180 // At least one method is live in this previous version.
3181 // Reset dead EMCP methods not to get breakpoints.
3182 // All methods are deallocated when all of the methods for this class are no
3183 // longer running.
3184 Array<Method*>* method_refs = pv_node->methods();
3185 if (method_refs != NULL) {
3186 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3187 method_refs->length()));
3188 for (int j = 0; j < method_refs->length(); j++) {
3189 Method* method = method_refs->at(j);
3190
3191 if (!method->on_stack()) {
3192 // no breakpoints for non-running methods
3193 if (method->is_running_emcp()) {
3194 method->set_running_emcp(false);
3195 }
3196 } else {
3197 assert (method->is_obsolete() || method->is_running_emcp(),
3198 "emcp method cannot run after emcp bit is cleared");
3199 // RC_TRACE macro has an embedded ResourceMark
3200 RC_TRACE(0x00000200,
3201 ("purge: %s(%s): prev method @%d in version @%d is alive",
3202 method->name()->as_C_string(),
3203 method->signature()->as_C_string(), j, version));
3204 }
3205 }
3206 }
3207 // next previous version
3208 last = pv_node;
3209 pv_node = pv_node->previous_versions();
3210 version++;
3211 }
3212 RC_TRACE(0x00000200,
3213 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3214 deleted_count));
3215 }
3216 }
3217
3218 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3219 int emcp_method_count) {
3220 int obsolete_method_count = old_methods->length() - emcp_method_count;
3221
3222 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3223 _previous_versions != NULL) {
3224 // We have a mix of obsolete and EMCP methods so we have to
3225 // clear out any matching EMCP method entries the hard way.
3226 int local_count = 0;
3227 for (int i = 0; i < old_methods->length(); i++) {
3228 Method* old_method = old_methods->at(i);
3229 if (old_method->is_obsolete()) {
3230 // only obsolete methods are interesting
3231 Symbol* m_name = old_method->name();
3232 Symbol* m_signature = old_method->signature();
3233
3234 // previous versions are linked together through the InstanceKlass
3235 int j = 0;
3236 for (InstanceKlass* prev_version = _previous_versions;
3237 prev_version != NULL;
3238 prev_version = prev_version->previous_versions(), j++) {
3239
3240 Array<Method*>* method_refs = prev_version->methods();
3241 for (int k = 0; k < method_refs->length(); k++) {
3242 Method* method = method_refs->at(k);
3243
3244 if (!method->is_obsolete() &&
3245 method->name() == m_name &&
3246 method->signature() == m_signature) {
3247 // The current RedefineClasses() call has made all EMCP
3248 // versions of this method obsolete so mark it as obsolete
3249 RC_TRACE(0x00000400,
3250 ("add: %s(%s): flush obsolete method @%d in version @%d",
3251 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3252
3253 method->set_is_obsolete();
3254 break;
3255 }
3256 }
3257
3258 // The previous loop may not find a matching EMCP method, but
3259 // that doesn't mean that we can optimize and not go any
3260 // further back in the PreviousVersion generations. The EMCP
3261 // method for this generation could have already been made obsolete,
3262 // but there still may be an older EMCP method that has not
3263 // been made obsolete.
3264 }
3265
3266 if (++local_count >= obsolete_method_count) {
3267 // no more obsolete methods so bail out now
3268 break;
3269 }
3270 }
3271 }
3272 }
3273 }
3274
3275 // Save the scratch_class as the previous version if any of the methods are running.
3276 // The previous_versions are used to set breakpoints in EMCP methods and they are
3277 // also used to clean MethodData links to redefined methods that are no longer running.
3278 void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class,
3279 int emcp_method_count) {
3280 assert(Thread::current()->is_VM_thread(),
3281 "only VMThread can add previous versions");
3282
3283 // RC_TRACE macro has an embedded ResourceMark
3284 RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d",
3285 scratch_class->external_name(), emcp_method_count));
3286
3287 // Clean out old previous versions
3288 purge_previous_versions(this);
3289
3290 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3291 // a previous redefinition may be made obsolete by this redefinition.
3292 Array<Method*>* old_methods = scratch_class->methods();
3293 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3294
3295 // If the constant pool for this previous version of the class
3296 // is not marked as being on the stack, then none of the methods
3297 // in this previous version of the class are on the stack so
3298 // we don't need to add this as a previous version.
3299 ConstantPool* cp_ref = scratch_class->constants();
3300 if (!cp_ref->on_stack()) {
3301 RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running"));
3302 // For debugging purposes.
3303 scratch_class->set_is_scratch_class();
3304 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class());
3305 // Update count for class unloading.
3306 _previous_version_count--;
3307 return;
3308 }
3309
3310 if (emcp_method_count != 0) {
3311 // At least one method is still running, check for EMCP methods
3312 for (int i = 0; i < old_methods->length(); i++) {
3313 Method* old_method = old_methods->at(i);
3314 if (!old_method->is_obsolete() && old_method->on_stack()) {
3315 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3316 // we can add breakpoints for it.
3317
3318 // We set the method->on_stack bit during safepoints for class redefinition
3319 // and use this bit to set the is_running_emcp bit.
3320 // After the safepoint, the on_stack bit is cleared and the running emcp
3321 // method may exit. If so, we would set a breakpoint in a method that
3322 // is never reached, but this won't be noticeable to the programmer.
3323 old_method->set_running_emcp(true);
3324 RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT,
3325 old_method->name_and_sig_as_C_string(), p2i(old_method)));
3326 } else if (!old_method->is_obsolete()) {
3327 RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT,
3328 old_method->name_and_sig_as_C_string(), p2i(old_method)));
3329 }
3330 }
3331 }
3332
3333 // Add previous version if any methods are still running.
3334 RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack"));
3335 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3336 scratch_class->link_previous_versions(previous_versions());
3337 link_previous_versions(scratch_class());
3338 // Update count for class unloading.
3339 _previous_version_count++;
3340 } // end add_previous_version()
3341
3342
3343 Method* InstanceKlass::method_with_idnum(int idnum) {
3344 Method* m = NULL;
3345 if (idnum < methods()->length()) {
3346 m = methods()->at(idnum);
3347 }
3348 if (m == NULL || m->method_idnum() != idnum) {
3349 for (int index = 0; index < methods()->length(); ++index) {
3350 m = methods()->at(index);
3351 if (m->method_idnum() == idnum) {
3352 return m;
3353 }
3354 }
3355 // None found, return null for the caller to handle.
3356 return NULL;
3357 }
3358 return m;
3359 }
3360
3361
3362 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3363 if (idnum >= methods()->length()) {
3364 return NULL;
3365 }
3366 Method* m = methods()->at(idnum);
3367 if (m != NULL && m->orig_method_idnum() == idnum) {
3368 return m;
3369 }
3370 // Obsolete method idnum does not match the original idnum
3371 for (int index = 0; index < methods()->length(); ++index) {
3372 m = methods()->at(index);
3373 if (m->orig_method_idnum() == idnum) {
3374 return m;
3375 }
3376 }
3377 // None found, return null for the caller to handle.
3378 return NULL;
3379 }
3380
3381
3382 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3383 InstanceKlass* holder = get_klass_version(version);
3384 if (holder == NULL) {
3385 return NULL; // The version of klass is gone, no method is found
3386 }
3387 Method* method = holder->method_with_orig_idnum(idnum);
3388 return method;
3389 }
3390
3391
3392 jint InstanceKlass::get_cached_class_file_len() {
3393 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3394 }
3395
3396 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3397 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3398 }