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