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