Wed, 02 Jan 2013 20:28:09 -0500
8005494: SIGSEGV in Rewriter::relocate_and_link() when testing Weblogic with CompressedOops and KlassPtrs
Summary: Relocate functions with jsr's when rewriting so not repeated after reading shared archive
Reviewed-by: twisti, jrose
1 /*
2 * Copyright (c) 1997, 2012, 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 */
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/verifier.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "gc_implementation/shared/markSweep.inline.hpp"
32 #include "gc_interface/collectedHeap.inline.hpp"
33 #include "interpreter/oopMapCache.hpp"
34 #include "interpreter/rewriter.hpp"
35 #include "jvmtifiles/jvmti.h"
36 #include "memory/genOopClosures.inline.hpp"
37 #include "memory/metadataFactory.hpp"
38 #include "memory/oopFactory.hpp"
39 #include "oops/fieldStreams.hpp"
40 #include "oops/instanceClassLoaderKlass.hpp"
41 #include "oops/instanceKlass.hpp"
42 #include "oops/instanceMirrorKlass.hpp"
43 #include "oops/instanceOop.hpp"
44 #include "oops/klass.inline.hpp"
45 #include "oops/method.hpp"
46 #include "oops/oop.inline.hpp"
47 #include "oops/symbol.hpp"
48 #include "prims/jvmtiExport.hpp"
49 #include "prims/jvmtiRedefineClassesTrace.hpp"
50 #include "prims/methodComparator.hpp"
51 #include "runtime/fieldDescriptor.hpp"
52 #include "runtime/handles.inline.hpp"
53 #include "runtime/javaCalls.hpp"
54 #include "runtime/mutexLocker.hpp"
55 #include "runtime/thread.inline.hpp"
56 #include "services/threadService.hpp"
57 #include "utilities/dtrace.hpp"
58 #ifndef SERIALGC
59 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
60 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
61 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
62 #include "gc_implementation/g1/g1RemSet.inline.hpp"
63 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
64 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
65 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
66 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
67 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
68 #include "oops/oop.pcgc.inline.hpp"
69 #endif
70 #ifdef COMPILER1
71 #include "c1/c1_Compiler.hpp"
72 #endif
74 #ifdef DTRACE_ENABLED
76 #ifndef USDT2
78 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
79 char*, intptr_t, oop, intptr_t);
80 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
81 char*, intptr_t, oop, intptr_t, int);
82 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
83 char*, intptr_t, oop, intptr_t, int);
84 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
85 char*, intptr_t, oop, intptr_t, int);
86 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
87 char*, intptr_t, oop, intptr_t, int);
88 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
89 char*, intptr_t, oop, intptr_t, int);
90 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
91 char*, intptr_t, oop, intptr_t, int);
92 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
93 char*, intptr_t, oop, intptr_t, int);
95 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
96 { \
97 char* data = NULL; \
98 int len = 0; \
99 Symbol* name = (clss)->name(); \
100 if (name != NULL) { \
101 data = (char*)name->bytes(); \
102 len = name->utf8_length(); \
103 } \
104 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \
105 data, len, (clss)->class_loader(), thread_type); \
106 }
108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
109 { \
110 char* data = NULL; \
111 int len = 0; \
112 Symbol* name = (clss)->name(); \
113 if (name != NULL) { \
114 data = (char*)name->bytes(); \
115 len = name->utf8_length(); \
116 } \
117 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \
118 data, len, (clss)->class_loader(), thread_type, wait); \
119 }
120 #else /* USDT2 */
122 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
123 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
124 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
125 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
126 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
127 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
128 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
129 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
130 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
131 { \
132 char* data = NULL; \
133 int len = 0; \
134 Symbol* name = (clss)->name(); \
135 if (name != NULL) { \
136 data = (char*)name->bytes(); \
137 len = name->utf8_length(); \
138 } \
139 HOTSPOT_CLASS_INITIALIZATION_##type( \
140 data, len, (clss)->class_loader(), thread_type); \
141 }
143 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
144 { \
145 char* data = NULL; \
146 int len = 0; \
147 Symbol* name = (clss)->name(); \
148 if (name != NULL) { \
149 data = (char*)name->bytes(); \
150 len = name->utf8_length(); \
151 } \
152 HOTSPOT_CLASS_INITIALIZATION_##type( \
153 data, len, (clss)->class_loader(), thread_type, wait); \
154 }
155 #endif /* USDT2 */
157 #else // ndef DTRACE_ENABLED
159 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
160 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
162 #endif // ndef DTRACE_ENABLED
164 Klass* InstanceKlass::allocate_instance_klass(ClassLoaderData* loader_data,
165 int vtable_len,
166 int itable_len,
167 int static_field_size,
168 int nonstatic_oop_map_size,
169 ReferenceType rt,
170 AccessFlags access_flags,
171 Symbol* name,
172 Klass* super_klass,
173 KlassHandle host_klass,
174 TRAPS) {
176 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
177 access_flags.is_interface(),
178 !host_klass.is_null());
180 // Allocation
181 InstanceKlass* ik;
182 if (rt == REF_NONE) {
183 if (name == vmSymbols::java_lang_Class()) {
184 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
185 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
186 access_flags, !host_klass.is_null());
187 } else if (name == vmSymbols::java_lang_ClassLoader() ||
188 (SystemDictionary::ClassLoader_klass_loaded() &&
189 super_klass != NULL &&
190 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
191 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
192 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
193 access_flags, !host_klass.is_null());
194 } else {
195 // normal class
196 ik = new (loader_data, size, THREAD) InstanceKlass(
197 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
198 access_flags, !host_klass.is_null());
199 }
200 } else {
201 // reference klass
202 ik = new (loader_data, size, THREAD) InstanceRefKlass(
203 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
204 access_flags, !host_klass.is_null());
205 }
207 return ik;
208 }
210 InstanceKlass::InstanceKlass(int vtable_len,
211 int itable_len,
212 int static_field_size,
213 int nonstatic_oop_map_size,
214 ReferenceType rt,
215 AccessFlags access_flags,
216 bool is_anonymous) {
217 No_Safepoint_Verifier no_safepoint; // until k becomes parsable
219 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
220 access_flags.is_interface(), is_anonymous);
222 // The sizes of these these three variables are used for determining the
223 // size of the instanceKlassOop. It is critical that these are set to the right
224 // sizes before the first GC, i.e., when we allocate the mirror.
225 this->set_vtable_length(vtable_len);
226 this->set_itable_length(itable_len);
227 this->set_static_field_size(static_field_size);
228 this->set_nonstatic_oop_map_size(nonstatic_oop_map_size);
229 this->set_access_flags(access_flags);
230 this->set_is_anonymous(is_anonymous);
231 assert(this->size() == size, "wrong size for object");
233 this->set_array_klasses(NULL);
234 this->set_methods(NULL);
235 this->set_method_ordering(NULL);
236 this->set_local_interfaces(NULL);
237 this->set_transitive_interfaces(NULL);
238 this->init_implementor();
239 this->set_fields(NULL, 0);
240 this->set_constants(NULL);
241 this->set_class_loader_data(NULL);
242 this->set_protection_domain(NULL);
243 this->set_signers(NULL);
244 this->set_source_file_name(NULL);
245 this->set_source_debug_extension(NULL, 0);
246 this->set_array_name(NULL);
247 this->set_inner_classes(NULL);
248 this->set_static_oop_field_count(0);
249 this->set_nonstatic_field_size(0);
250 this->set_is_marked_dependent(false);
251 this->set_init_state(InstanceKlass::allocated);
252 this->set_init_thread(NULL);
253 this->set_init_lock(NULL);
254 this->set_reference_type(rt);
255 this->set_oop_map_cache(NULL);
256 this->set_jni_ids(NULL);
257 this->set_osr_nmethods_head(NULL);
258 this->set_breakpoints(NULL);
259 this->init_previous_versions();
260 this->set_generic_signature(NULL);
261 this->release_set_methods_jmethod_ids(NULL);
262 this->release_set_methods_cached_itable_indices(NULL);
263 this->set_annotations(NULL);
264 this->set_jvmti_cached_class_field_map(NULL);
265 this->set_initial_method_idnum(0);
267 // initialize the non-header words to zero
268 intptr_t* p = (intptr_t*)this;
269 for (int index = InstanceKlass::header_size(); index < size; index++) {
270 p[index] = NULL_WORD;
271 }
273 // Set temporary value until parseClassFile updates it with the real instance
274 // size.
275 this->set_layout_helper(Klass::instance_layout_helper(0, true));
276 }
279 // This function deallocates the metadata and C heap pointers that the
280 // InstanceKlass points to.
281 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
283 // Orphan the mirror first, CMS thinks it's still live.
284 java_lang_Class::set_klass(java_mirror(), NULL);
286 // Need to take this class off the class loader data list.
287 loader_data->remove_class(this);
289 // The array_klass for this class is created later, after error handling.
290 // For class redefinition, we keep the original class so this scratch class
291 // doesn't have an array class. Either way, assert that there is nothing
292 // to deallocate.
293 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
295 // Release C heap allocated data that this might point to, which includes
296 // reference counting symbol names.
297 release_C_heap_structures();
299 Array<Method*>* ms = methods();
300 if (ms != Universe::the_empty_method_array()) {
301 for (int i = 0; i <= methods()->length() -1 ; i++) {
302 Method* method = methods()->at(i);
303 // Only want to delete methods that are not executing for RedefineClasses.
304 // The previous version will point to them so they're not totally dangling
305 assert (!method->on_stack(), "shouldn't be called with methods on stack");
306 MetadataFactory::free_metadata(loader_data, method);
307 }
308 MetadataFactory::free_array<Method*>(loader_data, methods());
309 }
310 set_methods(NULL);
312 if (method_ordering() != Universe::the_empty_int_array()) {
313 MetadataFactory::free_array<int>(loader_data, method_ordering());
314 }
315 set_method_ordering(NULL);
317 // This array is in Klass, but remove it with the InstanceKlass since
318 // this place would be the only caller and it can share memory with transitive
319 // interfaces.
320 if (secondary_supers() != Universe::the_empty_klass_array() &&
321 secondary_supers() != transitive_interfaces()) {
322 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
323 }
324 set_secondary_supers(NULL);
326 // Only deallocate transitive interfaces if not empty, same as super class
327 // or same as local interfaces. See code in parseClassFile.
328 Array<Klass*>* ti = transitive_interfaces();
329 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces()) {
330 // check that the interfaces don't come from super class
331 Array<Klass*>* sti = (super() == NULL) ? NULL :
332 InstanceKlass::cast(super())->transitive_interfaces();
333 if (ti != sti) {
334 MetadataFactory::free_array<Klass*>(loader_data, ti);
335 }
336 }
337 set_transitive_interfaces(NULL);
339 // local interfaces can be empty
340 Array<Klass*>* li = local_interfaces();
341 if (li != Universe::the_empty_klass_array()) {
342 MetadataFactory::free_array<Klass*>(loader_data, li);
343 }
344 set_local_interfaces(NULL);
346 MetadataFactory::free_array<jushort>(loader_data, fields());
347 set_fields(NULL, 0);
349 // If a method from a redefined class is using this constant pool, don't
350 // delete it, yet. The new class's previous version will point to this.
351 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
352 MetadataFactory::free_metadata(loader_data, constants());
353 set_constants(NULL);
355 if (inner_classes() != Universe::the_empty_short_array()) {
356 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
357 }
358 set_inner_classes(NULL);
360 // Null out Java heap objects, although these won't be walked to keep
361 // alive once this InstanceKlass is deallocated.
362 set_protection_domain(NULL);
363 set_signers(NULL);
364 set_init_lock(NULL);
366 // We should deallocate the Annotations instance
367 MetadataFactory::free_metadata(loader_data, annotations());
368 set_annotations(NULL);
369 }
371 volatile oop InstanceKlass::init_lock() const {
372 volatile oop lock = _init_lock; // read once
373 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
374 "only fully initialized state can have a null lock");
375 return lock;
376 }
378 // Set the initialization lock to null so the object can be GC'ed. Any racing
379 // threads to get this lock will see a null lock and will not lock.
380 // That's okay because they all check for initialized state after getting
381 // the lock and return.
382 void InstanceKlass::fence_and_clear_init_lock() {
383 // make sure previous stores are all done, notably the init_state.
384 OrderAccess::storestore();
385 klass_oop_store(&_init_lock, NULL);
386 assert(!is_not_initialized(), "class must be initialized now");
387 }
390 bool InstanceKlass::should_be_initialized() const {
391 return !is_initialized();
392 }
394 klassVtable* InstanceKlass::vtable() const {
395 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
396 }
398 klassItable* InstanceKlass::itable() const {
399 return new klassItable(instanceKlassHandle(this));
400 }
402 void InstanceKlass::eager_initialize(Thread *thread) {
403 if (!EagerInitialization) return;
405 if (this->is_not_initialized()) {
406 // abort if the the class has a class initializer
407 if (this->class_initializer() != NULL) return;
409 // abort if it is java.lang.Object (initialization is handled in genesis)
410 Klass* super = this->super();
411 if (super == NULL) return;
413 // abort if the super class should be initialized
414 if (!InstanceKlass::cast(super)->is_initialized()) return;
416 // call body to expose the this pointer
417 instanceKlassHandle this_oop(thread, this);
418 eager_initialize_impl(this_oop);
419 }
420 }
423 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
424 EXCEPTION_MARK;
425 volatile oop init_lock = this_oop->init_lock();
426 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
428 // abort if someone beat us to the initialization
429 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
431 ClassState old_state = this_oop->init_state();
432 link_class_impl(this_oop, true, THREAD);
433 if (HAS_PENDING_EXCEPTION) {
434 CLEAR_PENDING_EXCEPTION;
435 // Abort if linking the class throws an exception.
437 // Use a test to avoid redundantly resetting the state if there's
438 // no change. Set_init_state() asserts that state changes make
439 // progress, whereas here we might just be spinning in place.
440 if( old_state != this_oop->_init_state )
441 this_oop->set_init_state (old_state);
442 } else {
443 // linking successfull, mark class as initialized
444 this_oop->set_init_state (fully_initialized);
445 this_oop->fence_and_clear_init_lock();
446 // trace
447 if (TraceClassInitialization) {
448 ResourceMark rm(THREAD);
449 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
450 }
451 }
452 }
455 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
456 // process. The step comments refers to the procedure described in that section.
457 // Note: implementation moved to static method to expose the this pointer.
458 void InstanceKlass::initialize(TRAPS) {
459 if (this->should_be_initialized()) {
460 HandleMark hm(THREAD);
461 instanceKlassHandle this_oop(THREAD, this);
462 initialize_impl(this_oop, CHECK);
463 // Note: at this point the class may be initialized
464 // OR it may be in the state of being initialized
465 // in case of recursive initialization!
466 } else {
467 assert(is_initialized(), "sanity check");
468 }
469 }
472 bool InstanceKlass::verify_code(
473 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
474 // 1) Verify the bytecodes
475 Verifier::Mode mode =
476 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
477 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
478 }
481 // Used exclusively by the shared spaces dump mechanism to prevent
482 // classes mapped into the shared regions in new VMs from appearing linked.
484 void InstanceKlass::unlink_class() {
485 assert(is_linked(), "must be linked");
486 _init_state = loaded;
487 }
489 void InstanceKlass::link_class(TRAPS) {
490 assert(is_loaded(), "must be loaded");
491 if (!is_linked()) {
492 HandleMark hm(THREAD);
493 instanceKlassHandle this_oop(THREAD, this);
494 link_class_impl(this_oop, true, CHECK);
495 }
496 }
498 // Called to verify that a class can link during initialization, without
499 // throwing a VerifyError.
500 bool InstanceKlass::link_class_or_fail(TRAPS) {
501 assert(is_loaded(), "must be loaded");
502 if (!is_linked()) {
503 HandleMark hm(THREAD);
504 instanceKlassHandle this_oop(THREAD, this);
505 link_class_impl(this_oop, false, CHECK_false);
506 }
507 return is_linked();
508 }
510 bool InstanceKlass::link_class_impl(
511 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
512 // check for error state
513 if (this_oop->is_in_error_state()) {
514 ResourceMark rm(THREAD);
515 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
516 this_oop->external_name(), false);
517 }
518 // return if already verified
519 if (this_oop->is_linked()) {
520 return true;
521 }
523 // Timing
524 // timer handles recursion
525 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
526 JavaThread* jt = (JavaThread*)THREAD;
528 // link super class before linking this class
529 instanceKlassHandle super(THREAD, this_oop->super());
530 if (super.not_null()) {
531 if (super->is_interface()) { // check if super class is an interface
532 ResourceMark rm(THREAD);
533 Exceptions::fthrow(
534 THREAD_AND_LOCATION,
535 vmSymbols::java_lang_IncompatibleClassChangeError(),
536 "class %s has interface %s as super class",
537 this_oop->external_name(),
538 super->external_name()
539 );
540 return false;
541 }
543 link_class_impl(super, throw_verifyerror, CHECK_false);
544 }
546 // link all interfaces implemented by this class before linking this class
547 Array<Klass*>* interfaces = this_oop->local_interfaces();
548 int num_interfaces = interfaces->length();
549 for (int index = 0; index < num_interfaces; index++) {
550 HandleMark hm(THREAD);
551 instanceKlassHandle ih(THREAD, interfaces->at(index));
552 link_class_impl(ih, throw_verifyerror, CHECK_false);
553 }
555 // in case the class is linked in the process of linking its superclasses
556 if (this_oop->is_linked()) {
557 return true;
558 }
560 // trace only the link time for this klass that includes
561 // the verification time
562 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
563 ClassLoader::perf_class_link_selftime(),
564 ClassLoader::perf_classes_linked(),
565 jt->get_thread_stat()->perf_recursion_counts_addr(),
566 jt->get_thread_stat()->perf_timers_addr(),
567 PerfClassTraceTime::CLASS_LINK);
569 // verification & rewriting
570 {
571 volatile oop init_lock = this_oop->init_lock();
572 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
573 // rewritten will have been set if loader constraint error found
574 // on an earlier link attempt
575 // don't verify or rewrite if already rewritten
577 if (!this_oop->is_linked()) {
578 if (!this_oop->is_rewritten()) {
579 {
580 // Timer includes any side effects of class verification (resolution,
581 // etc), but not recursive entry into verify_code().
582 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
583 ClassLoader::perf_class_verify_selftime(),
584 ClassLoader::perf_classes_verified(),
585 jt->get_thread_stat()->perf_recursion_counts_addr(),
586 jt->get_thread_stat()->perf_timers_addr(),
587 PerfClassTraceTime::CLASS_VERIFY);
588 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
589 if (!verify_ok) {
590 return false;
591 }
592 }
594 // Just in case a side-effect of verify linked this class already
595 // (which can sometimes happen since the verifier loads classes
596 // using custom class loaders, which are free to initialize things)
597 if (this_oop->is_linked()) {
598 return true;
599 }
601 // also sets rewritten
602 this_oop->rewrite_class(CHECK_false);
603 }
605 // relocate jsrs and link methods after they are all rewritten
606 this_oop->link_methods(CHECK_false);
608 // Initialize the vtable and interface table after
609 // methods have been rewritten since rewrite may
610 // fabricate new Method*s.
611 // also does loader constraint checking
612 if (!this_oop()->is_shared()) {
613 ResourceMark rm(THREAD);
614 this_oop->vtable()->initialize_vtable(true, CHECK_false);
615 this_oop->itable()->initialize_itable(true, CHECK_false);
616 }
617 #ifdef ASSERT
618 else {
619 ResourceMark rm(THREAD);
620 this_oop->vtable()->verify(tty, true);
621 // In case itable verification is ever added.
622 // this_oop->itable()->verify(tty, true);
623 }
624 #endif
625 this_oop->set_init_state(linked);
626 if (JvmtiExport::should_post_class_prepare()) {
627 Thread *thread = THREAD;
628 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
629 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
630 }
631 }
632 }
633 return true;
634 }
637 // Rewrite the byte codes of all of the methods of a class.
638 // The rewriter must be called exactly once. Rewriting must happen after
639 // verification but before the first method of the class is executed.
640 void InstanceKlass::rewrite_class(TRAPS) {
641 assert(is_loaded(), "must be loaded");
642 instanceKlassHandle this_oop(THREAD, this);
643 if (this_oop->is_rewritten()) {
644 assert(this_oop()->is_shared(), "rewriting an unshared class?");
645 return;
646 }
647 Rewriter::rewrite(this_oop, CHECK);
648 this_oop->set_rewritten();
649 }
651 // Now relocate and link method entry points after class is rewritten.
652 // This is outside is_rewritten flag. In case of an exception, it can be
653 // executed more than once.
654 void InstanceKlass::link_methods(TRAPS) {
655 int len = methods()->length();
656 for (int i = len-1; i >= 0; i--) {
657 methodHandle m(THREAD, methods()->at(i));
659 // Set up method entry points for compiler and interpreter .
660 m->link_method(m, CHECK);
662 // This is for JVMTI and unrelated to relocator but the last thing we do
663 #ifdef ASSERT
664 if (StressMethodComparator) {
665 ResourceMark rm(THREAD);
666 static int nmc = 0;
667 for (int j = i; j >= 0 && j >= i-4; j--) {
668 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc);
669 bool z = MethodComparator::methods_EMCP(m(),
670 methods()->at(j));
671 if (j == i && !z) {
672 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
673 assert(z, "method must compare equal to itself");
674 }
675 }
676 }
677 #endif //ASSERT
678 }
679 }
682 void InstanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
683 // Make sure klass is linked (verified) before initialization
684 // A class could already be verified, since it has been reflected upon.
685 this_oop->link_class(CHECK);
687 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_oop()), -1);
689 bool wait = false;
691 // refer to the JVM book page 47 for description of steps
692 // Step 1
693 {
694 volatile oop init_lock = this_oop->init_lock();
695 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
697 Thread *self = THREAD; // it's passed the current thread
699 // Step 2
700 // If we were to use wait() instead of waitInterruptibly() then
701 // we might end up throwing IE from link/symbol resolution sites
702 // that aren't expected to throw. This would wreak havoc. See 6320309.
703 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
704 wait = true;
705 ol.waitUninterruptibly(CHECK);
706 }
708 // Step 3
709 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
710 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_oop()), -1,wait);
711 return;
712 }
714 // Step 4
715 if (this_oop->is_initialized()) {
716 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_oop()), -1,wait);
717 return;
718 }
720 // Step 5
721 if (this_oop->is_in_error_state()) {
722 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_oop()), -1,wait);
723 ResourceMark rm(THREAD);
724 const char* desc = "Could not initialize class ";
725 const char* className = this_oop->external_name();
726 size_t msglen = strlen(desc) + strlen(className) + 1;
727 char* message = NEW_RESOURCE_ARRAY(char, msglen);
728 if (NULL == message) {
729 // Out of memory: can't create detailed error message
730 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
731 } else {
732 jio_snprintf(message, msglen, "%s%s", desc, className);
733 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
734 }
735 }
737 // Step 6
738 this_oop->set_init_state(being_initialized);
739 this_oop->set_init_thread(self);
740 }
742 // Step 7
743 Klass* super_klass = this_oop->super();
744 if (super_klass != NULL && !this_oop->is_interface() && super_klass->should_be_initialized()) {
745 super_klass->initialize(THREAD);
747 if (HAS_PENDING_EXCEPTION) {
748 Handle e(THREAD, PENDING_EXCEPTION);
749 CLEAR_PENDING_EXCEPTION;
750 {
751 EXCEPTION_MARK;
752 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
753 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
754 }
755 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_oop()), -1,wait);
756 THROW_OOP(e());
757 }
758 }
760 if (this_oop->has_default_methods()) {
761 // Step 7.5: initialize any interfaces which have default methods
762 for (int i = 0; i < this_oop->local_interfaces()->length(); ++i) {
763 Klass* iface = this_oop->local_interfaces()->at(i);
764 InstanceKlass* ik = InstanceKlass::cast(iface);
765 if (ik->has_default_methods() && ik->should_be_initialized()) {
766 ik->initialize(THREAD);
768 if (HAS_PENDING_EXCEPTION) {
769 Handle e(THREAD, PENDING_EXCEPTION);
770 CLEAR_PENDING_EXCEPTION;
771 {
772 EXCEPTION_MARK;
773 // Locks object, set state, and notify all waiting threads
774 this_oop->set_initialization_state_and_notify(
775 initialization_error, THREAD);
777 // ignore any exception thrown, superclass initialization error is
778 // thrown below
779 CLEAR_PENDING_EXCEPTION;
780 }
781 DTRACE_CLASSINIT_PROBE_WAIT(
782 super__failed, InstanceKlass::cast(this_oop()), -1, wait);
783 THROW_OOP(e());
784 }
785 }
786 }
787 }
789 // Step 8
790 {
791 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
792 JavaThread* jt = (JavaThread*)THREAD;
793 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_oop()), -1,wait);
794 // Timer includes any side effects of class initialization (resolution,
795 // etc), but not recursive entry into call_class_initializer().
796 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
797 ClassLoader::perf_class_init_selftime(),
798 ClassLoader::perf_classes_inited(),
799 jt->get_thread_stat()->perf_recursion_counts_addr(),
800 jt->get_thread_stat()->perf_timers_addr(),
801 PerfClassTraceTime::CLASS_CLINIT);
802 this_oop->call_class_initializer(THREAD);
803 }
805 // Step 9
806 if (!HAS_PENDING_EXCEPTION) {
807 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
808 { ResourceMark rm(THREAD);
809 debug_only(this_oop->vtable()->verify(tty, true);)
810 }
811 }
812 else {
813 // Step 10 and 11
814 Handle e(THREAD, PENDING_EXCEPTION);
815 CLEAR_PENDING_EXCEPTION;
816 {
817 EXCEPTION_MARK;
818 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
819 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
820 }
821 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_oop()), -1,wait);
822 if (e->is_a(SystemDictionary::Error_klass())) {
823 THROW_OOP(e());
824 } else {
825 JavaCallArguments args(e);
826 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
827 vmSymbols::throwable_void_signature(),
828 &args);
829 }
830 }
831 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_oop()), -1,wait);
832 }
835 // Note: implementation moved to static method to expose the this pointer.
836 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
837 instanceKlassHandle kh(THREAD, this);
838 set_initialization_state_and_notify_impl(kh, state, CHECK);
839 }
841 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
842 volatile oop init_lock = this_oop->init_lock();
843 ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
844 this_oop->set_init_state(state);
845 this_oop->fence_and_clear_init_lock();
846 ol.notify_all(CHECK);
847 }
849 // The embedded _implementor field can only record one implementor.
850 // When there are more than one implementors, the _implementor field
851 // is set to the interface Klass* itself. Following are the possible
852 // values for the _implementor field:
853 // NULL - no implementor
854 // implementor Klass* - one implementor
855 // self - more than one implementor
856 //
857 // The _implementor field only exists for interfaces.
858 void InstanceKlass::add_implementor(Klass* k) {
859 assert(Compile_lock->owned_by_self(), "");
860 assert(is_interface(), "not interface");
861 // Filter out my subinterfaces.
862 // (Note: Interfaces are never on the subklass list.)
863 if (InstanceKlass::cast(k)->is_interface()) return;
865 // Filter out subclasses whose supers already implement me.
866 // (Note: CHA must walk subclasses of direct implementors
867 // in order to locate indirect implementors.)
868 Klass* sk = InstanceKlass::cast(k)->super();
869 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
870 // We only need to check one immediate superclass, since the
871 // implements_interface query looks at transitive_interfaces.
872 // Any supers of the super have the same (or fewer) transitive_interfaces.
873 return;
875 Klass* ik = implementor();
876 if (ik == NULL) {
877 set_implementor(k);
878 } else if (ik != this) {
879 // There is already an implementor. Use itself as an indicator of
880 // more than one implementors.
881 set_implementor(this);
882 }
884 // The implementor also implements the transitive_interfaces
885 for (int index = 0; index < local_interfaces()->length(); index++) {
886 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
887 }
888 }
890 void InstanceKlass::init_implementor() {
891 if (is_interface()) {
892 set_implementor(NULL);
893 }
894 }
897 void InstanceKlass::process_interfaces(Thread *thread) {
898 // link this class into the implementors list of every interface it implements
899 Klass* this_as_klass_oop = this;
900 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
901 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
902 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
903 assert(interf->is_interface(), "expected interface");
904 interf->add_implementor(this_as_klass_oop);
905 }
906 }
908 bool InstanceKlass::can_be_primary_super_slow() const {
909 if (is_interface())
910 return false;
911 else
912 return Klass::can_be_primary_super_slow();
913 }
915 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
916 // The secondaries are the implemented interfaces.
917 InstanceKlass* ik = InstanceKlass::cast(this);
918 Array<Klass*>* interfaces = ik->transitive_interfaces();
919 int num_secondaries = num_extra_slots + interfaces->length();
920 if (num_secondaries == 0) {
921 // Must share this for correct bootstrapping!
922 set_secondary_supers(Universe::the_empty_klass_array());
923 return NULL;
924 } else if (num_extra_slots == 0) {
925 // The secondary super list is exactly the same as the transitive interfaces.
926 // Redefine classes has to be careful not to delete this!
927 set_secondary_supers(interfaces);
928 return NULL;
929 } else {
930 // Copy transitive interfaces to a temporary growable array to be constructed
931 // into the secondary super list with extra slots.
932 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
933 for (int i = 0; i < interfaces->length(); i++) {
934 secondaries->push(interfaces->at(i));
935 }
936 return secondaries;
937 }
938 }
940 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
941 if (k->is_interface()) {
942 return implements_interface(k);
943 } else {
944 return Klass::compute_is_subtype_of(k);
945 }
946 }
948 bool InstanceKlass::implements_interface(Klass* k) const {
949 if (this == k) return true;
950 assert(k->is_interface(), "should be an interface class");
951 for (int i = 0; i < transitive_interfaces()->length(); i++) {
952 if (transitive_interfaces()->at(i) == k) {
953 return true;
954 }
955 }
956 return false;
957 }
959 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
960 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
961 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
962 report_java_out_of_memory("Requested array size exceeds VM limit");
963 JvmtiExport::post_array_size_exhausted();
964 THROW_OOP_0(Universe::out_of_memory_error_array_size());
965 }
966 int size = objArrayOopDesc::object_size(length);
967 Klass* ak = array_klass(n, CHECK_NULL);
968 KlassHandle h_ak (THREAD, ak);
969 objArrayOop o =
970 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
971 return o;
972 }
974 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
975 if (TraceFinalizerRegistration) {
976 tty->print("Registered ");
977 i->print_value_on(tty);
978 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
979 }
980 instanceHandle h_i(THREAD, i);
981 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
982 JavaValue result(T_VOID);
983 JavaCallArguments args(h_i);
984 methodHandle mh (THREAD, Universe::finalizer_register_method());
985 JavaCalls::call(&result, mh, &args, CHECK_NULL);
986 return h_i();
987 }
989 instanceOop InstanceKlass::allocate_instance(TRAPS) {
990 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
991 int size = size_helper(); // Query before forming handle.
993 KlassHandle h_k(THREAD, this);
995 instanceOop i;
997 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
998 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
999 i = register_finalizer(i, CHECK_NULL);
1000 }
1001 return i;
1002 }
1004 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1005 if (is_interface() || is_abstract()) {
1006 ResourceMark rm(THREAD);
1007 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1008 : vmSymbols::java_lang_InstantiationException(), external_name());
1009 }
1010 if (this == SystemDictionary::Class_klass()) {
1011 ResourceMark rm(THREAD);
1012 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1013 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1014 }
1015 }
1017 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1018 instanceKlassHandle this_oop(THREAD, this);
1019 return array_klass_impl(this_oop, or_null, n, THREAD);
1020 }
1022 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
1023 if (this_oop->array_klasses() == NULL) {
1024 if (or_null) return NULL;
1026 ResourceMark rm;
1027 JavaThread *jt = (JavaThread *)THREAD;
1028 {
1029 // Atomic creation of array_klasses
1030 MutexLocker mc(Compile_lock, THREAD); // for vtables
1031 MutexLocker ma(MultiArray_lock, THREAD);
1033 // Check if update has already taken place
1034 if (this_oop->array_klasses() == NULL) {
1035 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_oop->class_loader_data(), 1, this_oop, CHECK_NULL);
1036 this_oop->set_array_klasses(k);
1037 }
1038 }
1039 }
1040 // _this will always be set at this point
1041 ObjArrayKlass* oak = (ObjArrayKlass*)this_oop->array_klasses();
1042 if (or_null) {
1043 return oak->array_klass_or_null(n);
1044 }
1045 return oak->array_klass(n, CHECK_NULL);
1046 }
1048 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1049 return array_klass_impl(or_null, 1, THREAD);
1050 }
1052 void InstanceKlass::call_class_initializer(TRAPS) {
1053 instanceKlassHandle ik (THREAD, this);
1054 call_class_initializer_impl(ik, THREAD);
1055 }
1057 static int call_class_initializer_impl_counter = 0; // for debugging
1059 Method* InstanceKlass::class_initializer() {
1060 Method* clinit = find_method(
1061 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1062 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1063 return clinit;
1064 }
1065 return NULL;
1066 }
1068 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
1069 if (ReplayCompiles &&
1070 (ReplaySuppressInitializers == 1 ||
1071 ReplaySuppressInitializers >= 2 && this_oop->class_loader() != NULL)) {
1072 // Hide the existence of the initializer for the purpose of replaying the compile
1073 return;
1074 }
1076 methodHandle h_method(THREAD, this_oop->class_initializer());
1077 assert(!this_oop->is_initialized(), "we cannot initialize twice");
1078 if (TraceClassInitialization) {
1079 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1080 this_oop->name()->print_value();
1081 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
1082 }
1083 if (h_method() != NULL) {
1084 JavaCallArguments args; // No arguments
1085 JavaValue result(T_VOID);
1086 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1087 }
1088 }
1091 void InstanceKlass::mask_for(methodHandle method, int bci,
1092 InterpreterOopMap* entry_for) {
1093 // Dirty read, then double-check under a lock.
1094 if (_oop_map_cache == NULL) {
1095 // Otherwise, allocate a new one.
1096 MutexLocker x(OopMapCacheAlloc_lock);
1097 // First time use. Allocate a cache in C heap
1098 if (_oop_map_cache == NULL) {
1099 _oop_map_cache = new OopMapCache();
1100 }
1101 }
1102 // _oop_map_cache is constant after init; lookup below does is own locking.
1103 _oop_map_cache->lookup(method, bci, entry_for);
1104 }
1107 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1108 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1109 Symbol* f_name = fs.name();
1110 Symbol* f_sig = fs.signature();
1111 if (f_name == name && f_sig == sig) {
1112 fd->initialize(const_cast<InstanceKlass*>(this), fs.index());
1113 return true;
1114 }
1115 }
1116 return false;
1117 }
1120 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1121 const int n = local_interfaces()->length();
1122 for (int i = 0; i < n; i++) {
1123 Klass* intf1 = local_interfaces()->at(i);
1124 assert(intf1->is_interface(), "just checking type");
1125 // search for field in current interface
1126 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1127 assert(fd->is_static(), "interface field must be static");
1128 return intf1;
1129 }
1130 // search for field in direct superinterfaces
1131 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1132 if (intf2 != NULL) return intf2;
1133 }
1134 // otherwise field lookup fails
1135 return NULL;
1136 }
1139 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1140 // search order according to newest JVM spec (5.4.3.2, p.167).
1141 // 1) search for field in current klass
1142 if (find_local_field(name, sig, fd)) {
1143 return const_cast<InstanceKlass*>(this);
1144 }
1145 // 2) search for field recursively in direct superinterfaces
1146 { Klass* intf = find_interface_field(name, sig, fd);
1147 if (intf != NULL) return intf;
1148 }
1149 // 3) apply field lookup recursively if superclass exists
1150 { Klass* supr = super();
1151 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1152 }
1153 // 4) otherwise field lookup fails
1154 return NULL;
1155 }
1158 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1159 // search order according to newest JVM spec (5.4.3.2, p.167).
1160 // 1) search for field in current klass
1161 if (find_local_field(name, sig, fd)) {
1162 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1163 }
1164 // 2) search for field recursively in direct superinterfaces
1165 if (is_static) {
1166 Klass* intf = find_interface_field(name, sig, fd);
1167 if (intf != NULL) return intf;
1168 }
1169 // 3) apply field lookup recursively if superclass exists
1170 { Klass* supr = super();
1171 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1172 }
1173 // 4) otherwise field lookup fails
1174 return NULL;
1175 }
1178 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1179 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1180 if (fs.offset() == offset) {
1181 fd->initialize(const_cast<InstanceKlass*>(this), fs.index());
1182 if (fd->is_static() == is_static) return true;
1183 }
1184 }
1185 return false;
1186 }
1189 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1190 Klass* klass = const_cast<InstanceKlass*>(this);
1191 while (klass != NULL) {
1192 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1193 return true;
1194 }
1195 klass = klass->super();
1196 }
1197 return false;
1198 }
1201 void InstanceKlass::methods_do(void f(Method* method)) {
1202 int len = methods()->length();
1203 for (int index = 0; index < len; index++) {
1204 Method* m = methods()->at(index);
1205 assert(m->is_method(), "must be method");
1206 f(m);
1207 }
1208 }
1211 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1212 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1213 if (fs.access_flags().is_static()) {
1214 fieldDescriptor fd;
1215 fd.initialize(this, fs.index());
1216 cl->do_field(&fd);
1217 }
1218 }
1219 }
1222 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
1223 instanceKlassHandle h_this(THREAD, this);
1224 do_local_static_fields_impl(h_this, f, CHECK);
1225 }
1228 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
1229 for (JavaFieldStream fs(this_oop()); !fs.done(); fs.next()) {
1230 if (fs.access_flags().is_static()) {
1231 fieldDescriptor fd;
1232 fd.initialize(this_oop(), fs.index());
1233 f(&fd, CHECK);
1234 }
1235 }
1236 }
1239 static int compare_fields_by_offset(int* a, int* b) {
1240 return a[0] - b[0];
1241 }
1243 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1244 InstanceKlass* super = superklass();
1245 if (super != NULL) {
1246 super->do_nonstatic_fields(cl);
1247 }
1248 fieldDescriptor fd;
1249 int length = java_fields_count();
1250 // In DebugInfo nonstatic fields are sorted by offset.
1251 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1252 int j = 0;
1253 for (int i = 0; i < length; i += 1) {
1254 fd.initialize(this, i);
1255 if (!fd.is_static()) {
1256 fields_sorted[j + 0] = fd.offset();
1257 fields_sorted[j + 1] = i;
1258 j += 2;
1259 }
1260 }
1261 if (j > 0) {
1262 length = j;
1263 // _sort_Fn is defined in growableArray.hpp.
1264 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1265 for (int i = 0; i < length; i += 2) {
1266 fd.initialize(this, fields_sorted[i + 1]);
1267 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1268 cl->do_field(&fd);
1269 }
1270 }
1271 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
1272 }
1275 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1276 if (array_klasses() != NULL)
1277 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1278 }
1280 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1281 if (array_klasses() != NULL)
1282 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1283 }
1286 void InstanceKlass::with_array_klasses_do(void f(Klass* k)) {
1287 f(this);
1288 array_klasses_do(f);
1289 }
1291 #ifdef ASSERT
1292 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1293 int len = methods->length();
1294 for (int index = 0; index < len; index++) {
1295 Method* m = methods->at(index);
1296 assert(m->is_method(), "must be method");
1297 if (m->signature() == signature && m->name() == name) {
1298 return index;
1299 }
1300 }
1301 return -1;
1302 }
1303 #endif
1305 static int binary_search(Array<Method*>* methods, Symbol* name) {
1306 int len = methods->length();
1307 // methods are sorted, so do binary search
1308 int l = 0;
1309 int h = len - 1;
1310 while (l <= h) {
1311 int mid = (l + h) >> 1;
1312 Method* m = methods->at(mid);
1313 assert(m->is_method(), "must be method");
1314 int res = m->name()->fast_compare(name);
1315 if (res == 0) {
1316 return mid;
1317 } else if (res < 0) {
1318 l = mid + 1;
1319 } else {
1320 h = mid - 1;
1321 }
1322 }
1323 return -1;
1324 }
1326 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1327 return InstanceKlass::find_method(methods(), name, signature);
1328 }
1330 Method* InstanceKlass::find_method(
1331 Array<Method*>* methods, Symbol* name, Symbol* signature) {
1332 int hit = binary_search(methods, name);
1333 if (hit != -1) {
1334 Method* m = methods->at(hit);
1335 // Do linear search to find matching signature. First, quick check
1336 // for common case
1337 if (m->signature() == signature) return m;
1338 // search downwards through overloaded methods
1339 int i;
1340 for (i = hit - 1; i >= 0; --i) {
1341 Method* m = methods->at(i);
1342 assert(m->is_method(), "must be method");
1343 if (m->name() != name) break;
1344 if (m->signature() == signature) return m;
1345 }
1346 // search upwards
1347 for (i = hit + 1; i < methods->length(); ++i) {
1348 Method* m = methods->at(i);
1349 assert(m->is_method(), "must be method");
1350 if (m->name() != name) break;
1351 if (m->signature() == signature) return m;
1352 }
1353 // not found
1354 #ifdef ASSERT
1355 int index = linear_search(methods, name, signature);
1356 assert(index == -1, err_msg("binary search should have found entry %d", index));
1357 #endif
1358 }
1359 return NULL;
1360 }
1362 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1363 return find_method_by_name(methods(), name, end);
1364 }
1366 int InstanceKlass::find_method_by_name(
1367 Array<Method*>* methods, Symbol* name, int* end_ptr) {
1368 assert(end_ptr != NULL, "just checking");
1369 int start = binary_search(methods, name);
1370 int end = start + 1;
1371 if (start != -1) {
1372 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1373 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1374 *end_ptr = end;
1375 return start;
1376 }
1377 return -1;
1378 }
1380 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
1381 Klass* klass = const_cast<InstanceKlass*>(this);
1382 while (klass != NULL) {
1383 Method* method = InstanceKlass::cast(klass)->find_method(name, signature);
1384 if (method != NULL) return method;
1385 klass = InstanceKlass::cast(klass)->super();
1386 }
1387 return NULL;
1388 }
1390 // lookup a method in all the interfaces that this class implements
1391 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1392 Symbol* signature) const {
1393 Array<Klass*>* all_ifs = transitive_interfaces();
1394 int num_ifs = all_ifs->length();
1395 InstanceKlass *ik = NULL;
1396 for (int i = 0; i < num_ifs; i++) {
1397 ik = InstanceKlass::cast(all_ifs->at(i));
1398 Method* m = ik->lookup_method(name, signature);
1399 if (m != NULL) {
1400 return m;
1401 }
1402 }
1403 return NULL;
1404 }
1406 /* jni_id_for_impl for jfieldIds only */
1407 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1408 MutexLocker ml(JfieldIdCreation_lock);
1409 // Retry lookup after we got the lock
1410 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1411 if (probe == NULL) {
1412 // Slow case, allocate new static field identifier
1413 probe = new JNIid(this_oop(), offset, this_oop->jni_ids());
1414 this_oop->set_jni_ids(probe);
1415 }
1416 return probe;
1417 }
1420 /* jni_id_for for jfieldIds only */
1421 JNIid* InstanceKlass::jni_id_for(int offset) {
1422 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1423 if (probe == NULL) {
1424 probe = jni_id_for_impl(this, offset);
1425 }
1426 return probe;
1427 }
1429 u2 InstanceKlass::enclosing_method_data(int offset) {
1430 Array<jushort>* inner_class_list = inner_classes();
1431 if (inner_class_list == NULL) {
1432 return 0;
1433 }
1434 int length = inner_class_list->length();
1435 if (length % inner_class_next_offset == 0) {
1436 return 0;
1437 } else {
1438 int index = length - enclosing_method_attribute_size;
1439 assert(offset < enclosing_method_attribute_size, "invalid offset");
1440 return inner_class_list->at(index + offset);
1441 }
1442 }
1444 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1445 u2 method_index) {
1446 Array<jushort>* inner_class_list = inner_classes();
1447 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1448 int length = inner_class_list->length();
1449 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1450 int index = length - enclosing_method_attribute_size;
1451 inner_class_list->at_put(
1452 index + enclosing_method_class_index_offset, class_index);
1453 inner_class_list->at_put(
1454 index + enclosing_method_method_index_offset, method_index);
1455 }
1456 }
1458 // Lookup or create a jmethodID.
1459 // This code is called by the VMThread and JavaThreads so the
1460 // locking has to be done very carefully to avoid deadlocks
1461 // and/or other cache consistency problems.
1462 //
1463 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1464 size_t idnum = (size_t)method_h->method_idnum();
1465 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1466 size_t length = 0;
1467 jmethodID id = NULL;
1469 // We use a double-check locking idiom here because this cache is
1470 // performance sensitive. In the normal system, this cache only
1471 // transitions from NULL to non-NULL which is safe because we use
1472 // release_set_methods_jmethod_ids() to advertise the new cache.
1473 // A partially constructed cache should never be seen by a racing
1474 // thread. We also use release_store_ptr() to save a new jmethodID
1475 // in the cache so a partially constructed jmethodID should never be
1476 // seen either. Cache reads of existing jmethodIDs proceed without a
1477 // lock, but cache writes of a new jmethodID requires uniqueness and
1478 // creation of the cache itself requires no leaks so a lock is
1479 // generally acquired in those two cases.
1480 //
1481 // If the RedefineClasses() API has been used, then this cache can
1482 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1483 // Cache creation requires no leaks and we require safety between all
1484 // cache accesses and freeing of the old cache so a lock is generally
1485 // acquired when the RedefineClasses() API has been used.
1487 if (jmeths != NULL) {
1488 // the cache already exists
1489 if (!ik_h->idnum_can_increment()) {
1490 // the cache can't grow so we can just get the current values
1491 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1492 } else {
1493 // cache can grow so we have to be more careful
1494 if (Threads::number_of_threads() == 0 ||
1495 SafepointSynchronize::is_at_safepoint()) {
1496 // we're single threaded or at a safepoint - no locking needed
1497 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1498 } else {
1499 MutexLocker ml(JmethodIdCreation_lock);
1500 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1501 }
1502 }
1503 }
1504 // implied else:
1505 // we need to allocate a cache so default length and id values are good
1507 if (jmeths == NULL || // no cache yet
1508 length <= idnum || // cache is too short
1509 id == NULL) { // cache doesn't contain entry
1511 // This function can be called by the VMThread so we have to do all
1512 // things that might block on a safepoint before grabbing the lock.
1513 // Otherwise, we can deadlock with the VMThread or have a cache
1514 // consistency issue. These vars keep track of what we might have
1515 // to free after the lock is dropped.
1516 jmethodID to_dealloc_id = NULL;
1517 jmethodID* to_dealloc_jmeths = NULL;
1519 // may not allocate new_jmeths or use it if we allocate it
1520 jmethodID* new_jmeths = NULL;
1521 if (length <= idnum) {
1522 // allocate a new cache that might be used
1523 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1524 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1525 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1526 // cache size is stored in element[0], other elements offset by one
1527 new_jmeths[0] = (jmethodID)size;
1528 }
1530 // allocate a new jmethodID that might be used
1531 jmethodID new_id = NULL;
1532 if (method_h->is_old() && !method_h->is_obsolete()) {
1533 // The method passed in is old (but not obsolete), we need to use the current version
1534 Method* current_method = ik_h->method_with_idnum((int)idnum);
1535 assert(current_method != NULL, "old and but not obsolete, so should exist");
1536 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1537 } else {
1538 // It is the current version of the method or an obsolete method,
1539 // use the version passed in
1540 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1541 }
1543 if (Threads::number_of_threads() == 0 ||
1544 SafepointSynchronize::is_at_safepoint()) {
1545 // we're single threaded or at a safepoint - no locking needed
1546 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1547 &to_dealloc_id, &to_dealloc_jmeths);
1548 } else {
1549 MutexLocker ml(JmethodIdCreation_lock);
1550 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1551 &to_dealloc_id, &to_dealloc_jmeths);
1552 }
1554 // The lock has been dropped so we can free resources.
1555 // Free up either the old cache or the new cache if we allocated one.
1556 if (to_dealloc_jmeths != NULL) {
1557 FreeHeap(to_dealloc_jmeths);
1558 }
1559 // free up the new ID since it wasn't needed
1560 if (to_dealloc_id != NULL) {
1561 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1562 }
1563 }
1564 return id;
1565 }
1568 // Common code to fetch the jmethodID from the cache or update the
1569 // cache with the new jmethodID. This function should never do anything
1570 // that causes the caller to go to a safepoint or we can deadlock with
1571 // the VMThread or have cache consistency issues.
1572 //
1573 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1574 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1575 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1576 jmethodID** to_dealloc_jmeths_p) {
1577 assert(new_id != NULL, "sanity check");
1578 assert(to_dealloc_id_p != NULL, "sanity check");
1579 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1580 assert(Threads::number_of_threads() == 0 ||
1581 SafepointSynchronize::is_at_safepoint() ||
1582 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1584 // reacquire the cache - we are locked, single threaded or at a safepoint
1585 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1586 jmethodID id = NULL;
1587 size_t length = 0;
1589 if (jmeths == NULL || // no cache yet
1590 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1591 if (jmeths != NULL) {
1592 // copy any existing entries from the old cache
1593 for (size_t index = 0; index < length; index++) {
1594 new_jmeths[index+1] = jmeths[index+1];
1595 }
1596 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1597 }
1598 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1599 } else {
1600 // fetch jmethodID (if any) from the existing cache
1601 id = jmeths[idnum+1];
1602 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1603 }
1604 if (id == NULL) {
1605 // No matching jmethodID in the existing cache or we have a new
1606 // cache or we just grew the cache. This cache write is done here
1607 // by the first thread to win the foot race because a jmethodID
1608 // needs to be unique once it is generally available.
1609 id = new_id;
1611 // The jmethodID cache can be read while unlocked so we have to
1612 // make sure the new jmethodID is complete before installing it
1613 // in the cache.
1614 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1615 } else {
1616 *to_dealloc_id_p = new_id; // save new id for later delete
1617 }
1618 return id;
1619 }
1622 // Common code to get the jmethodID cache length and the jmethodID
1623 // value at index idnum if there is one.
1624 //
1625 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1626 size_t idnum, size_t *length_p, jmethodID* id_p) {
1627 assert(cache != NULL, "sanity check");
1628 assert(length_p != NULL, "sanity check");
1629 assert(id_p != NULL, "sanity check");
1631 // cache size is stored in element[0], other elements offset by one
1632 *length_p = (size_t)cache[0];
1633 if (*length_p <= idnum) { // cache is too short
1634 *id_p = NULL;
1635 } else {
1636 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1637 }
1638 }
1641 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1642 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1643 size_t idnum = (size_t)method->method_idnum();
1644 jmethodID* jmeths = methods_jmethod_ids_acquire();
1645 size_t length; // length assigned as debugging crumb
1646 jmethodID id = NULL;
1647 if (jmeths != NULL && // If there is a cache
1648 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1649 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1650 }
1651 return id;
1652 }
1655 // Cache an itable index
1656 void InstanceKlass::set_cached_itable_index(size_t idnum, int index) {
1657 int* indices = methods_cached_itable_indices_acquire();
1658 int* to_dealloc_indices = NULL;
1660 // We use a double-check locking idiom here because this cache is
1661 // performance sensitive. In the normal system, this cache only
1662 // transitions from NULL to non-NULL which is safe because we use
1663 // release_set_methods_cached_itable_indices() to advertise the
1664 // new cache. A partially constructed cache should never be seen
1665 // by a racing thread. Cache reads and writes proceed without a
1666 // lock, but creation of the cache itself requires no leaks so a
1667 // lock is generally acquired in that case.
1668 //
1669 // If the RedefineClasses() API has been used, then this cache can
1670 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1671 // Cache creation requires no leaks and we require safety between all
1672 // cache accesses and freeing of the old cache so a lock is generally
1673 // acquired when the RedefineClasses() API has been used.
1675 if (indices == NULL || idnum_can_increment()) {
1676 // we need a cache or the cache can grow
1677 MutexLocker ml(JNICachedItableIndex_lock);
1678 // reacquire the cache to see if another thread already did the work
1679 indices = methods_cached_itable_indices_acquire();
1680 size_t length = 0;
1681 // cache size is stored in element[0], other elements offset by one
1682 if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
1683 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1684 int* new_indices = NEW_C_HEAP_ARRAY(int, size+1, mtClass);
1685 new_indices[0] = (int)size;
1686 // copy any existing entries
1687 size_t i;
1688 for (i = 0; i < length; i++) {
1689 new_indices[i+1] = indices[i+1];
1690 }
1691 // Set all the rest to -1
1692 for (i = length; i < size; i++) {
1693 new_indices[i+1] = -1;
1694 }
1695 if (indices != NULL) {
1696 // We have an old cache to delete so save it for after we
1697 // drop the lock.
1698 to_dealloc_indices = indices;
1699 }
1700 release_set_methods_cached_itable_indices(indices = new_indices);
1701 }
1703 if (idnum_can_increment()) {
1704 // this cache can grow so we have to write to it safely
1705 indices[idnum+1] = index;
1706 }
1707 } else {
1708 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
1709 }
1711 if (!idnum_can_increment()) {
1712 // The cache cannot grow and this JNI itable index value does not
1713 // have to be unique like a jmethodID. If there is a race to set it,
1714 // it doesn't matter.
1715 indices[idnum+1] = index;
1716 }
1718 if (to_dealloc_indices != NULL) {
1719 // we allocated a new cache so free the old one
1720 FreeHeap(to_dealloc_indices);
1721 }
1722 }
1725 // Retrieve a cached itable index
1726 int InstanceKlass::cached_itable_index(size_t idnum) {
1727 int* indices = methods_cached_itable_indices_acquire();
1728 if (indices != NULL && ((size_t)indices[0]) > idnum) {
1729 // indices exist and are long enough, retrieve possible cached
1730 return indices[idnum+1];
1731 }
1732 return -1;
1733 }
1736 //
1737 // Walk the list of dependent nmethods searching for nmethods which
1738 // are dependent on the changes that were passed in and mark them for
1739 // deoptimization. Returns the number of nmethods found.
1740 //
1741 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1742 assert_locked_or_safepoint(CodeCache_lock);
1743 int found = 0;
1744 nmethodBucket* b = _dependencies;
1745 while (b != NULL) {
1746 nmethod* nm = b->get_nmethod();
1747 // since dependencies aren't removed until an nmethod becomes a zombie,
1748 // the dependency list may contain nmethods which aren't alive.
1749 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1750 if (TraceDependencies) {
1751 ResourceMark rm;
1752 tty->print_cr("Marked for deoptimization");
1753 tty->print_cr(" context = %s", this->external_name());
1754 changes.print();
1755 nm->print();
1756 nm->print_dependencies();
1757 }
1758 nm->mark_for_deoptimization();
1759 found++;
1760 }
1761 b = b->next();
1762 }
1763 return found;
1764 }
1767 //
1768 // Add an nmethodBucket to the list of dependencies for this nmethod.
1769 // It's possible that an nmethod has multiple dependencies on this klass
1770 // so a count is kept for each bucket to guarantee that creation and
1771 // deletion of dependencies is consistent.
1772 //
1773 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1774 assert_locked_or_safepoint(CodeCache_lock);
1775 nmethodBucket* b = _dependencies;
1776 nmethodBucket* last = NULL;
1777 while (b != NULL) {
1778 if (nm == b->get_nmethod()) {
1779 b->increment();
1780 return;
1781 }
1782 b = b->next();
1783 }
1784 _dependencies = new nmethodBucket(nm, _dependencies);
1785 }
1788 //
1789 // Decrement count of the nmethod in the dependency list and remove
1790 // the bucket competely when the count goes to 0. This method must
1791 // find a corresponding bucket otherwise there's a bug in the
1792 // recording of dependecies.
1793 //
1794 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
1795 assert_locked_or_safepoint(CodeCache_lock);
1796 nmethodBucket* b = _dependencies;
1797 nmethodBucket* last = NULL;
1798 while (b != NULL) {
1799 if (nm == b->get_nmethod()) {
1800 if (b->decrement() == 0) {
1801 if (last == NULL) {
1802 _dependencies = b->next();
1803 } else {
1804 last->set_next(b->next());
1805 }
1806 delete b;
1807 }
1808 return;
1809 }
1810 last = b;
1811 b = b->next();
1812 }
1813 #ifdef ASSERT
1814 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1815 nm->print();
1816 #endif // ASSERT
1817 ShouldNotReachHere();
1818 }
1821 #ifndef PRODUCT
1822 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1823 nmethodBucket* b = _dependencies;
1824 int idx = 0;
1825 while (b != NULL) {
1826 nmethod* nm = b->get_nmethod();
1827 tty->print("[%d] count=%d { ", idx++, b->count());
1828 if (!verbose) {
1829 nm->print_on(tty, "nmethod");
1830 tty->print_cr(" } ");
1831 } else {
1832 nm->print();
1833 nm->print_dependencies();
1834 tty->print_cr("--- } ");
1835 }
1836 b = b->next();
1837 }
1838 }
1841 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1842 nmethodBucket* b = _dependencies;
1843 while (b != NULL) {
1844 if (nm == b->get_nmethod()) {
1845 return true;
1846 }
1847 b = b->next();
1848 }
1849 return false;
1850 }
1851 #endif //PRODUCT
1854 // Garbage collection
1856 void InstanceKlass::oops_do(OopClosure* cl) {
1857 Klass::oops_do(cl);
1859 cl->do_oop(adr_protection_domain());
1860 cl->do_oop(adr_signers());
1861 cl->do_oop(adr_init_lock());
1863 // Don't walk the arrays since they are walked from the ClassLoaderData objects.
1864 }
1866 #ifdef ASSERT
1867 template <class T> void assert_is_in(T *p) {
1868 T heap_oop = oopDesc::load_heap_oop(p);
1869 if (!oopDesc::is_null(heap_oop)) {
1870 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1871 assert(Universe::heap()->is_in(o), "should be in heap");
1872 }
1873 }
1874 template <class T> void assert_is_in_closed_subset(T *p) {
1875 T heap_oop = oopDesc::load_heap_oop(p);
1876 if (!oopDesc::is_null(heap_oop)) {
1877 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1878 assert(Universe::heap()->is_in_closed_subset(o),
1879 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
1880 }
1881 }
1882 template <class T> void assert_is_in_reserved(T *p) {
1883 T heap_oop = oopDesc::load_heap_oop(p);
1884 if (!oopDesc::is_null(heap_oop)) {
1885 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1886 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1887 }
1888 }
1889 template <class T> void assert_nothing(T *p) {}
1891 #else
1892 template <class T> void assert_is_in(T *p) {}
1893 template <class T> void assert_is_in_closed_subset(T *p) {}
1894 template <class T> void assert_is_in_reserved(T *p) {}
1895 template <class T> void assert_nothing(T *p) {}
1896 #endif // ASSERT
1898 //
1899 // Macros that iterate over areas of oops which are specialized on type of
1900 // oop pointer either narrow or wide, depending on UseCompressedOops
1901 //
1902 // Parameters are:
1903 // T - type of oop to point to (either oop or narrowOop)
1904 // start_p - starting pointer for region to iterate over
1905 // count - number of oops or narrowOops to iterate over
1906 // do_oop - action to perform on each oop (it's arbitrary C code which
1907 // makes it more efficient to put in a macro rather than making
1908 // it a template function)
1909 // assert_fn - assert function which is template function because performance
1910 // doesn't matter when enabled.
1911 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1912 T, start_p, count, do_oop, \
1913 assert_fn) \
1914 { \
1915 T* p = (T*)(start_p); \
1916 T* const end = p + (count); \
1917 while (p < end) { \
1918 (assert_fn)(p); \
1919 do_oop; \
1920 ++p; \
1921 } \
1922 }
1924 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1925 T, start_p, count, do_oop, \
1926 assert_fn) \
1927 { \
1928 T* const start = (T*)(start_p); \
1929 T* p = start + (count); \
1930 while (start < p) { \
1931 --p; \
1932 (assert_fn)(p); \
1933 do_oop; \
1934 } \
1935 }
1937 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
1938 T, start_p, count, low, high, \
1939 do_oop, assert_fn) \
1940 { \
1941 T* const l = (T*)(low); \
1942 T* const h = (T*)(high); \
1943 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
1944 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
1945 "bounded region must be properly aligned"); \
1946 T* p = (T*)(start_p); \
1947 T* end = p + (count); \
1948 if (p < l) p = l; \
1949 if (end > h) end = h; \
1950 while (p < end) { \
1951 (assert_fn)(p); \
1952 do_oop; \
1953 ++p; \
1954 } \
1955 }
1958 // The following macros call specialized macros, passing either oop or
1959 // narrowOop as the specialization type. These test the UseCompressedOops
1960 // flag.
1961 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
1962 { \
1963 /* Compute oopmap block range. The common case \
1964 is nonstatic_oop_map_size == 1. */ \
1965 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1966 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
1967 if (UseCompressedOops) { \
1968 while (map < end_map) { \
1969 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
1970 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1971 do_oop, assert_fn) \
1972 ++map; \
1973 } \
1974 } else { \
1975 while (map < end_map) { \
1976 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
1977 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1978 do_oop, assert_fn) \
1979 ++map; \
1980 } \
1981 } \
1982 }
1984 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
1985 { \
1986 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
1987 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
1988 if (UseCompressedOops) { \
1989 while (start_map < map) { \
1990 --map; \
1991 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
1992 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1993 do_oop, assert_fn) \
1994 } \
1995 } else { \
1996 while (start_map < map) { \
1997 --map; \
1998 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
1999 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2000 do_oop, assert_fn) \
2001 } \
2002 } \
2003 }
2005 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
2006 assert_fn) \
2007 { \
2008 /* Compute oopmap block range. The common case is \
2009 nonstatic_oop_map_size == 1, so we accept the \
2010 usually non-existent extra overhead of examining \
2011 all the maps. */ \
2012 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
2013 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
2014 if (UseCompressedOops) { \
2015 while (map < end_map) { \
2016 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
2017 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
2018 low, high, \
2019 do_oop, assert_fn) \
2020 ++map; \
2021 } \
2022 } else { \
2023 while (map < end_map) { \
2024 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
2025 obj->obj_field_addr<oop>(map->offset()), map->count(), \
2026 low, high, \
2027 do_oop, assert_fn) \
2028 ++map; \
2029 } \
2030 } \
2031 }
2033 void InstanceKlass::oop_follow_contents(oop obj) {
2034 assert(obj != NULL, "can't follow the content of NULL object");
2035 MarkSweep::follow_klass(obj->klass());
2036 InstanceKlass_OOP_MAP_ITERATE( \
2037 obj, \
2038 MarkSweep::mark_and_push(p), \
2039 assert_is_in_closed_subset)
2040 }
2042 #ifndef SERIALGC
2043 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
2044 oop obj) {
2045 assert(obj != NULL, "can't follow the content of NULL object");
2046 PSParallelCompact::follow_klass(cm, obj->klass());
2047 // Only mark the header and let the scan of the meta-data mark
2048 // everything else.
2049 InstanceKlass_OOP_MAP_ITERATE( \
2050 obj, \
2051 PSParallelCompact::mark_and_push(cm, p), \
2052 assert_is_in)
2053 }
2054 #endif // SERIALGC
2056 // closure's do_metadata() method dictates whether the given closure should be
2057 // applied to the klass ptr in the object header.
2059 #define if_do_metadata_checked(closure, nv_suffix) \
2060 /* Make sure the non-virtual and the virtual versions match. */ \
2061 assert(closure->do_metadata##nv_suffix() == closure->do_metadata(), \
2062 "Inconsistency in do_metadata"); \
2063 if (closure->do_metadata##nv_suffix())
2065 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
2066 \
2067 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
2068 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2069 /* header */ \
2070 if_do_metadata_checked(closure, nv_suffix) { \
2071 closure->do_klass##nv_suffix(obj->klass()); \
2072 } \
2073 InstanceKlass_OOP_MAP_ITERATE( \
2074 obj, \
2075 SpecializationStats:: \
2076 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
2077 (closure)->do_oop##nv_suffix(p), \
2078 assert_is_in_closed_subset) \
2079 return size_helper(); \
2080 }
2082 #ifndef SERIALGC
2083 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
2084 \
2085 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
2086 OopClosureType* closure) { \
2087 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
2088 /* header */ \
2089 if_do_metadata_checked(closure, nv_suffix) { \
2090 closure->do_klass##nv_suffix(obj->klass()); \
2091 } \
2092 /* instance variables */ \
2093 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2094 obj, \
2095 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
2096 (closure)->do_oop##nv_suffix(p), \
2097 assert_is_in_closed_subset) \
2098 return size_helper(); \
2099 }
2100 #endif // !SERIALGC
2102 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
2103 \
2104 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
2105 OopClosureType* closure, \
2106 MemRegion mr) { \
2107 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
2108 if_do_metadata_checked(closure, nv_suffix) { \
2109 if (mr.contains(obj)) { \
2110 closure->do_klass##nv_suffix(obj->klass()); \
2111 } \
2112 } \
2113 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
2114 obj, mr.start(), mr.end(), \
2115 (closure)->do_oop##nv_suffix(p), \
2116 assert_is_in_closed_subset) \
2117 return size_helper(); \
2118 }
2120 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2121 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
2122 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2123 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
2124 #ifndef SERIALGC
2125 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2126 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
2127 #endif // !SERIALGC
2129 int InstanceKlass::oop_adjust_pointers(oop obj) {
2130 int size = size_helper();
2131 InstanceKlass_OOP_MAP_ITERATE( \
2132 obj, \
2133 MarkSweep::adjust_pointer(p), \
2134 assert_is_in)
2135 MarkSweep::adjust_klass(obj->klass());
2136 return size;
2137 }
2139 #ifndef SERIALGC
2140 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
2141 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
2142 obj, \
2143 if (PSScavenge::should_scavenge(p)) { \
2144 pm->claim_or_forward_depth(p); \
2145 }, \
2146 assert_nothing )
2147 }
2149 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
2150 int size = size_helper();
2151 InstanceKlass_OOP_MAP_ITERATE( \
2152 obj, \
2153 PSParallelCompact::adjust_pointer(p), \
2154 assert_is_in)
2155 obj->update_header(cm);
2156 return size;
2157 }
2159 #endif // SERIALGC
2161 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2162 assert(is_loader_alive(is_alive), "this klass should be live");
2163 if (is_interface()) {
2164 if (ClassUnloading) {
2165 Klass* impl = implementor();
2166 if (impl != NULL) {
2167 if (!impl->is_loader_alive(is_alive)) {
2168 // remove this guy
2169 *adr_implementor() = NULL;
2170 }
2171 }
2172 }
2173 }
2174 }
2176 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2177 #ifdef COMPILER2
2178 // Currently only used by C2.
2179 for (int m = 0; m < methods()->length(); m++) {
2180 MethodData* mdo = methods()->at(m)->method_data();
2181 if (mdo != NULL) {
2182 for (ProfileData* data = mdo->first_data();
2183 mdo->is_valid(data);
2184 data = mdo->next_data(data)) {
2185 data->clean_weak_klass_links(is_alive);
2186 }
2187 }
2188 }
2189 #else
2190 #ifdef ASSERT
2191 // Verify that we haven't started to use MDOs for C1.
2192 for (int m = 0; m < methods()->length(); m++) {
2193 MethodData* mdo = methods()->at(m)->method_data();
2194 assert(mdo == NULL, "Didn't expect C1 to use MDOs");
2195 }
2196 #endif // ASSERT
2197 #endif // !COMPILER2
2198 }
2201 static void remove_unshareable_in_class(Klass* k) {
2202 // remove klass's unshareable info
2203 k->remove_unshareable_info();
2204 }
2206 void InstanceKlass::remove_unshareable_info() {
2207 Klass::remove_unshareable_info();
2208 // Unlink the class
2209 if (is_linked()) {
2210 unlink_class();
2211 }
2212 init_implementor();
2214 constants()->remove_unshareable_info();
2216 for (int i = 0; i < methods()->length(); i++) {
2217 Method* m = methods()->at(i);
2218 m->remove_unshareable_info();
2219 }
2221 // Need to reinstate when reading back the class.
2222 set_init_lock(NULL);
2224 // do array classes also.
2225 array_klasses_do(remove_unshareable_in_class);
2226 }
2228 void restore_unshareable_in_class(Klass* k, TRAPS) {
2229 k->restore_unshareable_info(CHECK);
2230 }
2232 void InstanceKlass::restore_unshareable_info(TRAPS) {
2233 Klass::restore_unshareable_info(CHECK);
2234 instanceKlassHandle ik(THREAD, this);
2236 Array<Method*>* methods = ik->methods();
2237 int num_methods = methods->length();
2238 for (int index2 = 0; index2 < num_methods; ++index2) {
2239 methodHandle m(THREAD, methods->at(index2));
2240 m()->link_method(m, CHECK);
2241 // restore method's vtable by calling a virtual function
2242 m->restore_vtable();
2243 }
2244 if (JvmtiExport::has_redefined_a_class()) {
2245 // Reinitialize vtable because RedefineClasses may have changed some
2246 // entries in this vtable for super classes so the CDS vtable might
2247 // point to old or obsolete entries. RedefineClasses doesn't fix up
2248 // vtables in the shared system dictionary, only the main one.
2249 // It also redefines the itable too so fix that too.
2250 ResourceMark rm(THREAD);
2251 ik->vtable()->initialize_vtable(false, CHECK);
2252 ik->itable()->initialize_itable(false, CHECK);
2253 }
2255 // Allocate a simple java object for a lock.
2256 // This needs to be a java object because during class initialization
2257 // it can be held across a java call.
2258 typeArrayOop r = oopFactory::new_typeArray(T_INT, 0, CHECK);
2259 Handle h(THREAD, (oop)r);
2260 ik->set_init_lock(h());
2262 // restore constant pool resolved references
2263 ik->constants()->restore_unshareable_info(CHECK);
2265 ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2266 }
2268 static void clear_all_breakpoints(Method* m) {
2269 m->clear_all_breakpoints();
2270 }
2272 void InstanceKlass::release_C_heap_structures() {
2273 // Deallocate oop map cache
2274 if (_oop_map_cache != NULL) {
2275 delete _oop_map_cache;
2276 _oop_map_cache = NULL;
2277 }
2279 // Deallocate JNI identifiers for jfieldIDs
2280 JNIid::deallocate(jni_ids());
2281 set_jni_ids(NULL);
2283 jmethodID* jmeths = methods_jmethod_ids_acquire();
2284 if (jmeths != (jmethodID*)NULL) {
2285 release_set_methods_jmethod_ids(NULL);
2286 FreeHeap(jmeths);
2287 }
2289 int* indices = methods_cached_itable_indices_acquire();
2290 if (indices != (int*)NULL) {
2291 release_set_methods_cached_itable_indices(NULL);
2292 FreeHeap(indices);
2293 }
2295 // release dependencies
2296 nmethodBucket* b = _dependencies;
2297 _dependencies = NULL;
2298 while (b != NULL) {
2299 nmethodBucket* next = b->next();
2300 delete b;
2301 b = next;
2302 }
2304 // Deallocate breakpoint records
2305 if (breakpoints() != 0x0) {
2306 methods_do(clear_all_breakpoints);
2307 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2308 }
2310 // deallocate information about previous versions
2311 if (_previous_versions != NULL) {
2312 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2313 PreviousVersionNode * pv_node = _previous_versions->at(i);
2314 delete pv_node;
2315 }
2316 delete _previous_versions;
2317 _previous_versions = NULL;
2318 }
2320 // deallocate the cached class file
2321 if (_cached_class_file_bytes != NULL) {
2322 os::free(_cached_class_file_bytes, mtClass);
2323 _cached_class_file_bytes = NULL;
2324 _cached_class_file_len = 0;
2325 }
2327 // Decrement symbol reference counts associated with the unloaded class.
2328 if (_name != NULL) _name->decrement_refcount();
2329 // unreference array name derived from this class name (arrays of an unloaded
2330 // class can't be referenced anymore).
2331 if (_array_name != NULL) _array_name->decrement_refcount();
2332 if (_source_file_name != NULL) _source_file_name->decrement_refcount();
2333 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
2334 }
2336 void InstanceKlass::set_source_file_name(Symbol* n) {
2337 _source_file_name = n;
2338 if (_source_file_name != NULL) _source_file_name->increment_refcount();
2339 }
2341 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2342 if (array == NULL) {
2343 _source_debug_extension = NULL;
2344 } else {
2345 // Adding one to the attribute length in order to store a null terminator
2346 // character could cause an overflow because the attribute length is
2347 // already coded with an u4 in the classfile, but in practice, it's
2348 // unlikely to happen.
2349 assert((length+1) > length, "Overflow checking");
2350 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2351 for (int i = 0; i < length; i++) {
2352 sde[i] = array[i];
2353 }
2354 sde[length] = '\0';
2355 _source_debug_extension = sde;
2356 }
2357 }
2359 address InstanceKlass::static_field_addr(int offset) {
2360 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + (intptr_t)java_mirror());
2361 }
2364 const char* InstanceKlass::signature_name() const {
2365 const char* src = (const char*) (name()->as_C_string());
2366 const int src_length = (int)strlen(src);
2367 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
2368 int src_index = 0;
2369 int dest_index = 0;
2370 dest[dest_index++] = 'L';
2371 while (src_index < src_length) {
2372 dest[dest_index++] = src[src_index++];
2373 }
2374 dest[dest_index++] = ';';
2375 dest[dest_index] = '\0';
2376 return dest;
2377 }
2379 // different verisons of is_same_class_package
2380 bool InstanceKlass::is_same_class_package(Klass* class2) {
2381 Klass* class1 = this;
2382 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2383 Symbol* classname1 = class1->name();
2385 if (class2->oop_is_objArray()) {
2386 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2387 }
2388 oop classloader2;
2389 if (class2->oop_is_instance()) {
2390 classloader2 = InstanceKlass::cast(class2)->class_loader();
2391 } else {
2392 assert(class2->oop_is_typeArray(), "should be type array");
2393 classloader2 = NULL;
2394 }
2395 Symbol* classname2 = class2->name();
2397 return InstanceKlass::is_same_class_package(classloader1, classname1,
2398 classloader2, classname2);
2399 }
2401 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2402 Klass* class1 = this;
2403 oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2404 Symbol* classname1 = class1->name();
2406 return InstanceKlass::is_same_class_package(classloader1, classname1,
2407 classloader2, classname2);
2408 }
2410 // return true if two classes are in the same package, classloader
2411 // and classname information is enough to determine a class's package
2412 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2413 oop class_loader2, Symbol* class_name2) {
2414 if (class_loader1 != class_loader2) {
2415 return false;
2416 } else if (class_name1 == class_name2) {
2417 return true; // skip painful bytewise comparison
2418 } else {
2419 ResourceMark rm;
2421 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2422 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2423 // Otherwise, we just compare jbyte values between the strings.
2424 const jbyte *name1 = class_name1->base();
2425 const jbyte *name2 = class_name2->base();
2427 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2428 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2430 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2431 // One of the two doesn't have a package. Only return true
2432 // if the other one also doesn't have a package.
2433 return last_slash1 == last_slash2;
2434 } else {
2435 // Skip over '['s
2436 if (*name1 == '[') {
2437 do {
2438 name1++;
2439 } while (*name1 == '[');
2440 if (*name1 != 'L') {
2441 // Something is terribly wrong. Shouldn't be here.
2442 return false;
2443 }
2444 }
2445 if (*name2 == '[') {
2446 do {
2447 name2++;
2448 } while (*name2 == '[');
2449 if (*name2 != 'L') {
2450 // Something is terribly wrong. Shouldn't be here.
2451 return false;
2452 }
2453 }
2455 // Check that package part is identical
2456 int length1 = last_slash1 - name1;
2457 int length2 = last_slash2 - name2;
2459 return UTF8::equal(name1, length1, name2, length2);
2460 }
2461 }
2462 }
2464 // Returns true iff super_method can be overridden by a method in targetclassname
2465 // See JSL 3rd edition 8.4.6.1
2466 // Assumes name-signature match
2467 // "this" is InstanceKlass of super_method which must exist
2468 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2469 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2470 // Private methods can not be overridden
2471 if (super_method->is_private()) {
2472 return false;
2473 }
2474 // If super method is accessible, then override
2475 if ((super_method->is_protected()) ||
2476 (super_method->is_public())) {
2477 return true;
2478 }
2479 // Package-private methods are not inherited outside of package
2480 assert(super_method->is_package_private(), "must be package private");
2481 return(is_same_class_package(targetclassloader(), targetclassname));
2482 }
2484 /* defined for now in jvm.cpp, for historical reasons *--
2485 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2486 Symbol*& simple_name_result, TRAPS) {
2487 ...
2488 }
2489 */
2491 // tell if two classes have the same enclosing class (at package level)
2492 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2493 Klass* class2_oop, TRAPS) {
2494 if (class2_oop == class1()) return true;
2495 if (!class2_oop->oop_is_instance()) return false;
2496 instanceKlassHandle class2(THREAD, class2_oop);
2498 // must be in same package before we try anything else
2499 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2500 return false;
2502 // As long as there is an outer1.getEnclosingClass,
2503 // shift the search outward.
2504 instanceKlassHandle outer1 = class1;
2505 for (;;) {
2506 // As we walk along, look for equalities between outer1 and class2.
2507 // Eventually, the walks will terminate as outer1 stops
2508 // at the top-level class around the original class.
2509 bool ignore_inner_is_member;
2510 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2511 CHECK_false);
2512 if (next == NULL) break;
2513 if (next == class2()) return true;
2514 outer1 = instanceKlassHandle(THREAD, next);
2515 }
2517 // Now do the same for class2.
2518 instanceKlassHandle outer2 = class2;
2519 for (;;) {
2520 bool ignore_inner_is_member;
2521 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2522 CHECK_false);
2523 if (next == NULL) break;
2524 // Might as well check the new outer against all available values.
2525 if (next == class1()) return true;
2526 if (next == outer1()) return true;
2527 outer2 = instanceKlassHandle(THREAD, next);
2528 }
2530 // If by this point we have not found an equality between the
2531 // two classes, we know they are in separate package members.
2532 return false;
2533 }
2536 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2537 jint access = access_flags().as_int();
2539 // But check if it happens to be member class.
2540 instanceKlassHandle ik(THREAD, this);
2541 InnerClassesIterator iter(ik);
2542 for (; !iter.done(); iter.next()) {
2543 int ioff = iter.inner_class_info_index();
2544 // Inner class attribute can be zero, skip it.
2545 // Strange but true: JVM spec. allows null inner class refs.
2546 if (ioff == 0) continue;
2548 // only look at classes that are already loaded
2549 // since we are looking for the flags for our self.
2550 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2551 if ((ik->name() == inner_name)) {
2552 // This is really a member class.
2553 access = iter.inner_access_flags();
2554 break;
2555 }
2556 }
2557 // Remember to strip ACC_SUPER bit
2558 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2559 }
2561 jint InstanceKlass::jvmti_class_status() const {
2562 jint result = 0;
2564 if (is_linked()) {
2565 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2566 }
2568 if (is_initialized()) {
2569 assert(is_linked(), "Class status is not consistent");
2570 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2571 }
2572 if (is_in_error_state()) {
2573 result |= JVMTI_CLASS_STATUS_ERROR;
2574 }
2575 return result;
2576 }
2578 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2579 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2580 int method_table_offset_in_words = ioe->offset()/wordSize;
2581 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2582 / itableOffsetEntry::size();
2584 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2585 // If the interface isn't implemented by the receiver class,
2586 // the VM should throw IncompatibleClassChangeError.
2587 if (cnt >= nof_interfaces) {
2588 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2589 }
2591 Klass* ik = ioe->interface_klass();
2592 if (ik == holder) break;
2593 }
2595 itableMethodEntry* ime = ioe->first_method_entry(this);
2596 Method* m = ime[index].method();
2597 if (m == NULL) {
2598 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2599 }
2600 return m;
2601 }
2603 // On-stack replacement stuff
2604 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2605 // only one compilation can be active
2606 NEEDS_CLEANUP
2607 // This is a short non-blocking critical region, so the no safepoint check is ok.
2608 OsrList_lock->lock_without_safepoint_check();
2609 assert(n->is_osr_method(), "wrong kind of nmethod");
2610 n->set_osr_link(osr_nmethods_head());
2611 set_osr_nmethods_head(n);
2612 // Raise the highest osr level if necessary
2613 if (TieredCompilation) {
2614 Method* m = n->method();
2615 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2616 }
2617 // Remember to unlock again
2618 OsrList_lock->unlock();
2620 // Get rid of the osr methods for the same bci that have lower levels.
2621 if (TieredCompilation) {
2622 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2623 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2624 if (inv != NULL && inv->is_in_use()) {
2625 inv->make_not_entrant();
2626 }
2627 }
2628 }
2629 }
2632 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2633 // This is a short non-blocking critical region, so the no safepoint check is ok.
2634 OsrList_lock->lock_without_safepoint_check();
2635 assert(n->is_osr_method(), "wrong kind of nmethod");
2636 nmethod* last = NULL;
2637 nmethod* cur = osr_nmethods_head();
2638 int max_level = CompLevel_none; // Find the max comp level excluding n
2639 Method* m = n->method();
2640 // Search for match
2641 while(cur != NULL && cur != n) {
2642 if (TieredCompilation) {
2643 // Find max level before n
2644 max_level = MAX2(max_level, cur->comp_level());
2645 }
2646 last = cur;
2647 cur = cur->osr_link();
2648 }
2649 nmethod* next = NULL;
2650 if (cur == n) {
2651 next = cur->osr_link();
2652 if (last == NULL) {
2653 // Remove first element
2654 set_osr_nmethods_head(next);
2655 } else {
2656 last->set_osr_link(next);
2657 }
2658 }
2659 n->set_osr_link(NULL);
2660 if (TieredCompilation) {
2661 cur = next;
2662 while (cur != NULL) {
2663 // Find max level after n
2664 max_level = MAX2(max_level, cur->comp_level());
2665 cur = cur->osr_link();
2666 }
2667 m->set_highest_osr_comp_level(max_level);
2668 }
2669 // Remember to unlock again
2670 OsrList_lock->unlock();
2671 }
2673 nmethod* InstanceKlass::lookup_osr_nmethod(Method* const m, int bci, int comp_level, bool match_level) const {
2674 // This is a short non-blocking critical region, so the no safepoint check is ok.
2675 OsrList_lock->lock_without_safepoint_check();
2676 nmethod* osr = osr_nmethods_head();
2677 nmethod* best = NULL;
2678 while (osr != NULL) {
2679 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2680 // There can be a time when a c1 osr method exists but we are waiting
2681 // for a c2 version. When c2 completes its osr nmethod we will trash
2682 // the c1 version and only be able to find the c2 version. However
2683 // while we overflow in the c1 code at back branches we don't want to
2684 // try and switch to the same code as we are already running
2686 if (osr->method() == m &&
2687 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2688 if (match_level) {
2689 if (osr->comp_level() == comp_level) {
2690 // Found a match - return it.
2691 OsrList_lock->unlock();
2692 return osr;
2693 }
2694 } else {
2695 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2696 if (osr->comp_level() == CompLevel_highest_tier) {
2697 // Found the best possible - return it.
2698 OsrList_lock->unlock();
2699 return osr;
2700 }
2701 best = osr;
2702 }
2703 }
2704 }
2705 osr = osr->osr_link();
2706 }
2707 OsrList_lock->unlock();
2708 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2709 return best;
2710 }
2711 return NULL;
2712 }
2714 // -----------------------------------------------------------------------------------------------------
2715 // Printing
2717 #ifndef PRODUCT
2719 #define BULLET " - "
2721 static const char* state_names[] = {
2722 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2723 };
2725 void InstanceKlass::print_on(outputStream* st) const {
2726 assert(is_klass(), "must be klass");
2727 Klass::print_on(st);
2729 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2730 st->print(BULLET"klass size: %d", size()); st->cr();
2731 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2732 st->print(BULLET"state: "); st->print_cr(state_names[_init_state]);
2733 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2734 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2735 st->print(BULLET"sub: ");
2736 Klass* sub = subklass();
2737 int n;
2738 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2739 if (n < MaxSubklassPrintSize) {
2740 sub->print_value_on(st);
2741 st->print(" ");
2742 }
2743 }
2744 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
2745 st->cr();
2747 if (is_interface()) {
2748 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2749 if (nof_implementors() == 1) {
2750 st->print_cr(BULLET"implementor: ");
2751 st->print(" ");
2752 implementor()->print_value_on(st);
2753 st->cr();
2754 }
2755 }
2757 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2758 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
2759 if (Verbose) {
2760 Array<Method*>* method_array = methods();
2761 for(int i = 0; i < method_array->length(); i++) {
2762 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2763 }
2764 }
2765 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
2766 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
2767 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2768 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
2769 if (class_loader_data() != NULL) {
2770 st->print(BULLET"class loader data: ");
2771 class_loader_data()->print_value_on(st);
2772 st->cr();
2773 }
2774 st->print(BULLET"protection domain: "); ((InstanceKlass*)this)->protection_domain()->print_value_on(st); st->cr();
2775 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
2776 st->print(BULLET"signers: "); signers()->print_value_on(st); st->cr();
2777 st->print(BULLET"init_lock: "); ((oop)init_lock())->print_value_on(st); st->cr();
2778 if (source_file_name() != NULL) {
2779 st->print(BULLET"source file: ");
2780 source_file_name()->print_value_on(st);
2781 st->cr();
2782 }
2783 if (source_debug_extension() != NULL) {
2784 st->print(BULLET"source debug extension: ");
2785 st->print("%s", source_debug_extension());
2786 st->cr();
2787 }
2788 st->print(BULLET"annotations: "); annotations()->print_value_on(st); st->cr();
2789 {
2790 ResourceMark rm;
2791 // PreviousVersionInfo objects returned via PreviousVersionWalker
2792 // contain a GrowableArray of handles. We have to clean up the
2793 // GrowableArray _after_ the PreviousVersionWalker destructor
2794 // has destroyed the handles.
2795 {
2796 bool have_pv = false;
2797 PreviousVersionWalker pvw((InstanceKlass*)this);
2798 for (PreviousVersionInfo * pv_info = pvw.next_previous_version();
2799 pv_info != NULL; pv_info = pvw.next_previous_version()) {
2800 if (!have_pv)
2801 st->print(BULLET"previous version: ");
2802 have_pv = true;
2803 pv_info->prev_constant_pool_handle()()->print_value_on(st);
2804 }
2805 if (have_pv) st->cr();
2806 } // pvw is cleaned up
2807 } // rm is cleaned up
2809 if (generic_signature() != NULL) {
2810 st->print(BULLET"generic signature: ");
2811 generic_signature()->print_value_on(st);
2812 st->cr();
2813 }
2814 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
2815 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
2816 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr();
2817 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
2818 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2819 FieldPrinter print_static_field(st);
2820 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2821 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2822 FieldPrinter print_nonstatic_field(st);
2823 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
2825 st->print(BULLET"non-static oop maps: ");
2826 OopMapBlock* map = start_of_nonstatic_oop_maps();
2827 OopMapBlock* end_map = map + nonstatic_oop_map_count();
2828 while (map < end_map) {
2829 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2830 map++;
2831 }
2832 st->cr();
2833 }
2835 #endif //PRODUCT
2837 void InstanceKlass::print_value_on(outputStream* st) const {
2838 assert(is_klass(), "must be klass");
2839 name()->print_value_on(st);
2840 }
2842 #ifndef PRODUCT
2844 void FieldPrinter::do_field(fieldDescriptor* fd) {
2845 _st->print(BULLET);
2846 if (_obj == NULL) {
2847 fd->print_on(_st);
2848 _st->cr();
2849 } else {
2850 fd->print_on_for(_st, _obj);
2851 _st->cr();
2852 }
2853 }
2856 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2857 Klass::oop_print_on(obj, st);
2859 if (this == SystemDictionary::String_klass()) {
2860 typeArrayOop value = java_lang_String::value(obj);
2861 juint offset = java_lang_String::offset(obj);
2862 juint length = java_lang_String::length(obj);
2863 if (value != NULL &&
2864 value->is_typeArray() &&
2865 offset <= (juint) value->length() &&
2866 offset + length <= (juint) value->length()) {
2867 st->print(BULLET"string: ");
2868 Handle h_obj(obj);
2869 java_lang_String::print(h_obj, st);
2870 st->cr();
2871 if (!WizardMode) return; // that is enough
2872 }
2873 }
2875 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2876 FieldPrinter print_field(st, obj);
2877 do_nonstatic_fields(&print_field);
2879 if (this == SystemDictionary::Class_klass()) {
2880 st->print(BULLET"signature: ");
2881 java_lang_Class::print_signature(obj, st);
2882 st->cr();
2883 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2884 st->print(BULLET"fake entry for mirror: ");
2885 mirrored_klass->print_value_on_maybe_null(st);
2886 st->cr();
2887 st->print(BULLET"fake entry resolved_constructor: ");
2888 Method* ctor = java_lang_Class::resolved_constructor(obj);
2889 ctor->print_value_on_maybe_null(st);
2890 Klass* array_klass = java_lang_Class::array_klass(obj);
2891 st->cr();
2892 st->print(BULLET"fake entry for array: ");
2893 array_klass->print_value_on_maybe_null(st);
2894 st->cr();
2895 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2896 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2897 Klass* real_klass = java_lang_Class::as_Klass(obj);
2898 if (real_klass != NULL && real_klass->oop_is_instance()) {
2899 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2900 }
2901 } else if (this == SystemDictionary::MethodType_klass()) {
2902 st->print(BULLET"signature: ");
2903 java_lang_invoke_MethodType::print_signature(obj, st);
2904 st->cr();
2905 }
2906 }
2908 #endif //PRODUCT
2910 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2911 st->print("a ");
2912 name()->print_value_on(st);
2913 obj->print_address_on(st);
2914 if (this == SystemDictionary::String_klass()
2915 && java_lang_String::value(obj) != NULL) {
2916 ResourceMark rm;
2917 int len = java_lang_String::length(obj);
2918 int plen = (len < 24 ? len : 12);
2919 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2920 st->print(" = \"%s\"", str);
2921 if (len > plen)
2922 st->print("...[%d]", len);
2923 } else if (this == SystemDictionary::Class_klass()) {
2924 Klass* k = java_lang_Class::as_Klass(obj);
2925 st->print(" = ");
2926 if (k != NULL) {
2927 k->print_value_on(st);
2928 } else {
2929 const char* tname = type2name(java_lang_Class::primitive_type(obj));
2930 st->print("%s", tname ? tname : "type?");
2931 }
2932 } else if (this == SystemDictionary::MethodType_klass()) {
2933 st->print(" = ");
2934 java_lang_invoke_MethodType::print_signature(obj, st);
2935 } else if (java_lang_boxing_object::is_instance(obj)) {
2936 st->print(" = ");
2937 java_lang_boxing_object::print(obj, st);
2938 } else if (this == SystemDictionary::LambdaForm_klass()) {
2939 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
2940 if (vmentry != NULL) {
2941 st->print(" => ");
2942 vmentry->print_value_on(st);
2943 }
2944 } else if (this == SystemDictionary::MemberName_klass()) {
2945 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
2946 if (vmtarget != NULL) {
2947 st->print(" = ");
2948 vmtarget->print_value_on(st);
2949 } else {
2950 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
2951 st->print(".");
2952 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
2953 }
2954 }
2955 }
2957 const char* InstanceKlass::internal_name() const {
2958 return external_name();
2959 }
2961 // Verification
2963 class VerifyFieldClosure: public OopClosure {
2964 protected:
2965 template <class T> void do_oop_work(T* p) {
2966 oop obj = oopDesc::load_decode_heap_oop(p);
2967 if (!obj->is_oop_or_null()) {
2968 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
2969 Universe::print();
2970 guarantee(false, "boom");
2971 }
2972 }
2973 public:
2974 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
2975 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2976 };
2978 void InstanceKlass::verify_on(outputStream* st) {
2979 Klass::verify_on(st);
2980 Thread *thread = Thread::current();
2982 #ifndef PRODUCT
2983 // Avoid redundant verifies
2984 if (_verify_count == Universe::verify_count()) return;
2985 _verify_count = Universe::verify_count();
2986 #endif
2987 // Verify that klass is present in SystemDictionary
2988 if (is_loaded() && !is_anonymous()) {
2989 Symbol* h_name = name();
2990 SystemDictionary::verify_obj_klass_present(h_name, class_loader_data());
2991 }
2993 // Verify static fields
2994 VerifyFieldClosure blk;
2996 // Verify vtables
2997 if (is_linked()) {
2998 ResourceMark rm(thread);
2999 // $$$ This used to be done only for m/s collections. Doing it
3000 // always seemed a valid generalization. (DLD -- 6/00)
3001 vtable()->verify(st);
3002 }
3004 // Verify first subklass
3005 if (subklass_oop() != NULL) {
3006 guarantee(subklass_oop()->is_metadata(), "should be in metaspace");
3007 guarantee(subklass_oop()->is_klass(), "should be klass");
3008 }
3010 // Verify siblings
3011 Klass* super = this->super();
3012 Klass* sib = next_sibling();
3013 if (sib != NULL) {
3014 if (sib == this) {
3015 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
3016 }
3018 guarantee(sib->is_metadata(), "should be in metaspace");
3019 guarantee(sib->is_klass(), "should be klass");
3020 guarantee(sib->super() == super, "siblings should have same superklass");
3021 }
3023 // Verify implementor fields
3024 Klass* im = implementor();
3025 if (im != NULL) {
3026 guarantee(is_interface(), "only interfaces should have implementor set");
3027 guarantee(im->is_klass(), "should be klass");
3028 guarantee(!im->is_interface() || im == this,
3029 "implementors cannot be interfaces");
3030 }
3032 // Verify local interfaces
3033 if (local_interfaces()) {
3034 Array<Klass*>* local_interfaces = this->local_interfaces();
3035 for (int j = 0; j < local_interfaces->length(); j++) {
3036 Klass* e = local_interfaces->at(j);
3037 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3038 }
3039 }
3041 // Verify transitive interfaces
3042 if (transitive_interfaces() != NULL) {
3043 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3044 for (int j = 0; j < transitive_interfaces->length(); j++) {
3045 Klass* e = transitive_interfaces->at(j);
3046 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3047 }
3048 }
3050 // Verify methods
3051 if (methods() != NULL) {
3052 Array<Method*>* methods = this->methods();
3053 for (int j = 0; j < methods->length(); j++) {
3054 guarantee(methods->at(j)->is_metadata(), "should be in metaspace");
3055 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3056 }
3057 for (int j = 0; j < methods->length() - 1; j++) {
3058 Method* m1 = methods->at(j);
3059 Method* m2 = methods->at(j + 1);
3060 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3061 }
3062 }
3064 // Verify method ordering
3065 if (method_ordering() != NULL) {
3066 Array<int>* method_ordering = this->method_ordering();
3067 int length = method_ordering->length();
3068 if (JvmtiExport::can_maintain_original_method_order() ||
3069 (UseSharedSpaces && length != 0)) {
3070 guarantee(length == methods()->length(), "invalid method ordering length");
3071 jlong sum = 0;
3072 for (int j = 0; j < length; j++) {
3073 int original_index = method_ordering->at(j);
3074 guarantee(original_index >= 0, "invalid method ordering index");
3075 guarantee(original_index < length, "invalid method ordering index");
3076 sum += original_index;
3077 }
3078 // Verify sum of indices 0,1,...,length-1
3079 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3080 } else {
3081 guarantee(length == 0, "invalid method ordering length");
3082 }
3083 }
3085 // Verify JNI static field identifiers
3086 if (jni_ids() != NULL) {
3087 jni_ids()->verify(this);
3088 }
3090 // Verify other fields
3091 if (array_klasses() != NULL) {
3092 guarantee(array_klasses()->is_metadata(), "should be in metaspace");
3093 guarantee(array_klasses()->is_klass(), "should be klass");
3094 }
3095 if (constants() != NULL) {
3096 guarantee(constants()->is_metadata(), "should be in metaspace");
3097 guarantee(constants()->is_constantPool(), "should be constant pool");
3098 }
3099 if (protection_domain() != NULL) {
3100 guarantee(protection_domain()->is_oop(), "should be oop");
3101 }
3102 if (host_klass() != NULL) {
3103 guarantee(host_klass()->is_metadata(), "should be in metaspace");
3104 guarantee(host_klass()->is_klass(), "should be klass");
3105 }
3106 if (signers() != NULL) {
3107 guarantee(signers()->is_objArray(), "should be obj array");
3108 }
3109 }
3111 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3112 Klass::oop_verify_on(obj, st);
3113 VerifyFieldClosure blk;
3114 obj->oop_iterate_no_header(&blk);
3115 }
3118 // JNIid class for jfieldIDs only
3119 // Note to reviewers:
3120 // These JNI functions are just moved over to column 1 and not changed
3121 // in the compressed oops workspace.
3122 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3123 _holder = holder;
3124 _offset = offset;
3125 _next = next;
3126 debug_only(_is_static_field_id = false;)
3127 }
3130 JNIid* JNIid::find(int offset) {
3131 JNIid* current = this;
3132 while (current != NULL) {
3133 if (current->offset() == offset) return current;
3134 current = current->next();
3135 }
3136 return NULL;
3137 }
3139 void JNIid::deallocate(JNIid* current) {
3140 while (current != NULL) {
3141 JNIid* next = current->next();
3142 delete current;
3143 current = next;
3144 }
3145 }
3148 void JNIid::verify(Klass* holder) {
3149 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3150 int end_field_offset;
3151 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3153 JNIid* current = this;
3154 while (current != NULL) {
3155 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3156 #ifdef ASSERT
3157 int o = current->offset();
3158 if (current->is_static_field_id()) {
3159 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3160 }
3161 #endif
3162 current = current->next();
3163 }
3164 }
3167 #ifdef ASSERT
3168 void InstanceKlass::set_init_state(ClassState state) {
3169 bool good_state = is_shared() ? (_init_state <= state)
3170 : (_init_state < state);
3171 assert(good_state || state == allocated, "illegal state transition");
3172 _init_state = (u1)state;
3173 }
3174 #endif
3177 // RedefineClasses() support for previous versions:
3179 // Purge previous versions
3180 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
3181 if (ik->previous_versions() != NULL) {
3182 // This klass has previous versions so see what we can cleanup
3183 // while it is safe to do so.
3185 int deleted_count = 0; // leave debugging breadcrumbs
3186 int live_count = 0;
3187 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
3188 ClassLoaderData::the_null_class_loader_data() :
3189 ik->class_loader_data();
3191 // RC_TRACE macro has an embedded ResourceMark
3192 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
3193 ik->external_name(), ik->previous_versions()->length()));
3195 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
3196 // check the previous versions array
3197 PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
3198 ConstantPool* cp_ref = pv_node->prev_constant_pool();
3199 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
3201 ConstantPool* pvcp = cp_ref;
3202 if (!pvcp->on_stack()) {
3203 // If the constant pool isn't on stack, none of the methods
3204 // are executing. Delete all the methods, the constant pool and
3205 // and this previous version node.
3206 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3207 if (method_refs != NULL) {
3208 for (int j = method_refs->length() - 1; j >= 0; j--) {
3209 Method* method = method_refs->at(j);
3210 assert(method != NULL, "method ref was unexpectedly cleared");
3211 method_refs->remove_at(j);
3212 // method will be freed with associated class.
3213 }
3214 }
3215 // Remove the constant pool
3216 delete pv_node;
3217 // Since we are traversing the array backwards, we don't have to
3218 // do anything special with the index.
3219 ik->previous_versions()->remove_at(i);
3220 deleted_count++;
3221 continue;
3222 } else {
3223 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
3224 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3225 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3226 live_count++;
3227 }
3229 // At least one method is live in this previous version, clean out
3230 // the others or mark them as obsolete.
3231 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3232 if (method_refs != NULL) {
3233 RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3234 method_refs->length()));
3235 for (int j = method_refs->length() - 1; j >= 0; j--) {
3236 Method* method = method_refs->at(j);
3237 assert(method != NULL, "method ref was unexpectedly cleared");
3239 // Remove the emcp method if it's not executing
3240 // If it's been made obsolete by a redefinition of a non-emcp
3241 // method, mark it as obsolete but leave it to clean up later.
3242 if (!method->on_stack()) {
3243 method_refs->remove_at(j);
3244 } else if (emcp_method_count == 0) {
3245 method->set_is_obsolete();
3246 } else {
3247 // RC_TRACE macro has an embedded ResourceMark
3248 RC_TRACE(0x00000200,
3249 ("purge: %s(%s): prev method @%d in version @%d is alive",
3250 method->name()->as_C_string(),
3251 method->signature()->as_C_string(), j, i));
3252 }
3253 }
3254 }
3255 }
3256 assert(ik->previous_versions()->length() == live_count, "sanity check");
3257 RC_TRACE(0x00000200,
3258 ("purge: previous version stats: live=%d, deleted=%d", live_count,
3259 deleted_count));
3260 }
3261 }
3263 // External interface for use during class unloading.
3264 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3265 // Call with >0 emcp methods since they are not currently being redefined.
3266 purge_previous_versions_internal(ik, 1);
3267 }
3270 // Potentially add an information node that contains pointers to the
3271 // interesting parts of the previous version of the_class.
3272 // This is also where we clean out any unused references.
3273 // Note that while we delete nodes from the _previous_versions
3274 // array, we never delete the array itself until the klass is
3275 // unloaded. The has_been_redefined() query depends on that fact.
3276 //
3277 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
3278 BitMap* emcp_methods, int emcp_method_count) {
3279 assert(Thread::current()->is_VM_thread(),
3280 "only VMThread can add previous versions");
3282 if (_previous_versions == NULL) {
3283 // This is the first previous version so make some space.
3284 // Start with 2 elements under the assumption that the class
3285 // won't be redefined much.
3286 _previous_versions = new (ResourceObj::C_HEAP, mtClass)
3287 GrowableArray<PreviousVersionNode *>(2, true);
3288 }
3290 ConstantPool* cp_ref = ikh->constants();
3292 // RC_TRACE macro has an embedded ResourceMark
3293 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
3294 "on_stack=%d",
3295 ikh->external_name(), _previous_versions->length(), emcp_method_count,
3296 cp_ref->on_stack()));
3298 // If the constant pool for this previous version of the class
3299 // is not marked as being on the stack, then none of the methods
3300 // in this previous version of the class are on the stack so
3301 // we don't need to create a new PreviousVersionNode. However,
3302 // we still need to examine older previous versions below.
3303 Array<Method*>* old_methods = ikh->methods();
3305 if (cp_ref->on_stack()) {
3306 PreviousVersionNode * pv_node = NULL;
3307 if (emcp_method_count == 0) {
3308 // non-shared ConstantPool gets a reference
3309 pv_node = new PreviousVersionNode(cp_ref, !cp_ref->is_shared(), NULL);
3310 RC_TRACE(0x00000400,
3311 ("add: all methods are obsolete; flushing any EMCP refs"));
3312 } else {
3313 int local_count = 0;
3314 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
3315 GrowableArray<Method*>(emcp_method_count, true);
3316 for (int i = 0; i < old_methods->length(); i++) {
3317 if (emcp_methods->at(i)) {
3318 // this old method is EMCP. Save it only if it's on the stack
3319 Method* old_method = old_methods->at(i);
3320 if (old_method->on_stack()) {
3321 method_refs->append(old_method);
3322 }
3323 if (++local_count >= emcp_method_count) {
3324 // no more EMCP methods so bail out now
3325 break;
3326 }
3327 }
3328 }
3329 // non-shared ConstantPool gets a reference
3330 pv_node = new PreviousVersionNode(cp_ref, !cp_ref->is_shared(), method_refs);
3331 }
3332 // append new previous version.
3333 _previous_versions->append(pv_node);
3334 }
3336 // Since the caller is the VMThread and we are at a safepoint, this
3337 // is a good time to clear out unused references.
3339 RC_TRACE(0x00000400, ("add: previous version length=%d",
3340 _previous_versions->length()));
3342 // Purge previous versions not executing on the stack
3343 purge_previous_versions_internal(this, emcp_method_count);
3345 int obsolete_method_count = old_methods->length() - emcp_method_count;
3347 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3348 _previous_versions->length() > 0) {
3349 // We have a mix of obsolete and EMCP methods so we have to
3350 // clear out any matching EMCP method entries the hard way.
3351 int local_count = 0;
3352 for (int i = 0; i < old_methods->length(); i++) {
3353 if (!emcp_methods->at(i)) {
3354 // only obsolete methods are interesting
3355 Method* old_method = old_methods->at(i);
3356 Symbol* m_name = old_method->name();
3357 Symbol* m_signature = old_method->signature();
3359 // we might not have added the last entry
3360 for (int j = _previous_versions->length() - 1; j >= 0; j--) {
3361 // check the previous versions array for non executing obsolete methods
3362 PreviousVersionNode * pv_node = _previous_versions->at(j);
3364 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3365 if (method_refs == NULL) {
3366 // We have run into a PreviousVersion generation where
3367 // all methods were made obsolete during that generation's
3368 // RedefineClasses() operation. At the time of that
3369 // operation, all EMCP methods were flushed so we don't
3370 // have to go back any further.
3371 //
3372 // A NULL method_refs is different than an empty method_refs.
3373 // We cannot infer any optimizations about older generations
3374 // from an empty method_refs for the current generation.
3375 break;
3376 }
3378 for (int k = method_refs->length() - 1; k >= 0; k--) {
3379 Method* method = method_refs->at(k);
3381 if (!method->is_obsolete() &&
3382 method->name() == m_name &&
3383 method->signature() == m_signature) {
3384 // The current RedefineClasses() call has made all EMCP
3385 // versions of this method obsolete so mark it as obsolete
3386 // and remove the reference.
3387 RC_TRACE(0x00000400,
3388 ("add: %s(%s): flush obsolete method @%d in version @%d",
3389 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3391 method->set_is_obsolete();
3392 // Leave obsolete methods on the previous version list to
3393 // clean up later.
3394 break;
3395 }
3396 }
3398 // The previous loop may not find a matching EMCP method, but
3399 // that doesn't mean that we can optimize and not go any
3400 // further back in the PreviousVersion generations. The EMCP
3401 // method for this generation could have already been deleted,
3402 // but there still may be an older EMCP method that has not
3403 // been deleted.
3404 }
3406 if (++local_count >= obsolete_method_count) {
3407 // no more obsolete methods so bail out now
3408 break;
3409 }
3410 }
3411 }
3412 }
3413 } // end add_previous_version()
3416 // Determine if InstanceKlass has a previous version.
3417 bool InstanceKlass::has_previous_version() const {
3418 return (_previous_versions != NULL && _previous_versions->length() > 0);
3419 } // end has_previous_version()
3422 Method* InstanceKlass::method_with_idnum(int idnum) {
3423 Method* m = NULL;
3424 if (idnum < methods()->length()) {
3425 m = methods()->at(idnum);
3426 }
3427 if (m == NULL || m->method_idnum() != idnum) {
3428 for (int index = 0; index < methods()->length(); ++index) {
3429 m = methods()->at(index);
3430 if (m->method_idnum() == idnum) {
3431 return m;
3432 }
3433 }
3434 }
3435 return m;
3436 }
3439 // Construct a PreviousVersionNode entry for the array hung off
3440 // the InstanceKlass.
3441 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
3442 bool prev_cp_is_weak, GrowableArray<Method*>* prev_EMCP_methods) {
3444 _prev_constant_pool = prev_constant_pool;
3445 _prev_cp_is_weak = prev_cp_is_weak;
3446 _prev_EMCP_methods = prev_EMCP_methods;
3447 }
3450 // Destroy a PreviousVersionNode
3451 PreviousVersionNode::~PreviousVersionNode() {
3452 if (_prev_constant_pool != NULL) {
3453 _prev_constant_pool = NULL;
3454 }
3456 if (_prev_EMCP_methods != NULL) {
3457 delete _prev_EMCP_methods;
3458 }
3459 }
3462 // Construct a PreviousVersionInfo entry
3463 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
3464 _prev_constant_pool_handle = constantPoolHandle(); // NULL handle
3465 _prev_EMCP_method_handles = NULL;
3467 ConstantPool* cp = pv_node->prev_constant_pool();
3468 assert(cp != NULL, "constant pool ref was unexpectedly cleared");
3469 if (cp == NULL) {
3470 return; // robustness
3471 }
3473 // make the ConstantPool* safe to return
3474 _prev_constant_pool_handle = constantPoolHandle(cp);
3476 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
3477 if (method_refs == NULL) {
3478 // the InstanceKlass did not have any EMCP methods
3479 return;
3480 }
3482 _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
3484 int n_methods = method_refs->length();
3485 for (int i = 0; i < n_methods; i++) {
3486 Method* method = method_refs->at(i);
3487 assert (method != NULL, "method has been cleared");
3488 if (method == NULL) {
3489 continue; // robustness
3490 }
3491 // make the Method* safe to return
3492 _prev_EMCP_method_handles->append(methodHandle(method));
3493 }
3494 }
3497 // Destroy a PreviousVersionInfo
3498 PreviousVersionInfo::~PreviousVersionInfo() {
3499 // Since _prev_EMCP_method_handles is not C-heap allocated, we
3500 // don't have to delete it.
3501 }
3504 // Construct a helper for walking the previous versions array
3505 PreviousVersionWalker::PreviousVersionWalker(InstanceKlass *ik) {
3506 _previous_versions = ik->previous_versions();
3507 _current_index = 0;
3508 // _hm needs no initialization
3509 _current_p = NULL;
3510 }
3513 // Destroy a PreviousVersionWalker
3514 PreviousVersionWalker::~PreviousVersionWalker() {
3515 // Delete the current info just in case the caller didn't walk to
3516 // the end of the previous versions list. No harm if _current_p is
3517 // already NULL.
3518 delete _current_p;
3520 // When _hm is destroyed, all the Handles returned in
3521 // PreviousVersionInfo objects will be destroyed.
3522 // Also, after this destructor is finished it will be
3523 // safe to delete the GrowableArray allocated in the
3524 // PreviousVersionInfo objects.
3525 }
3528 // Return the interesting information for the next previous version
3529 // of the klass. Returns NULL if there are no more previous versions.
3530 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
3531 if (_previous_versions == NULL) {
3532 // no previous versions so nothing to return
3533 return NULL;
3534 }
3536 delete _current_p; // cleanup the previous info for the caller
3537 _current_p = NULL; // reset to NULL so we don't delete same object twice
3539 int length = _previous_versions->length();
3541 while (_current_index < length) {
3542 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
3543 PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP, mtClass)
3544 PreviousVersionInfo(pv_node);
3546 constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
3547 assert (!cp_h.is_null(), "null cp found in previous version");
3549 // The caller will need to delete pv_info when they are done with it.
3550 _current_p = pv_info;
3551 return pv_info;
3552 }
3554 // all of the underlying nodes' info has been deleted
3555 return NULL;
3556 } // end next_previous_version()