Sat, 17 Mar 2012 17:31:59 -0400
Merge
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/oopFactory.hpp"
38 #include "memory/permGen.hpp"
39 #include "oops/fieldStreams.hpp"
40 #include "oops/instanceKlass.hpp"
41 #include "oops/instanceMirrorKlass.hpp"
42 #include "oops/instanceOop.hpp"
43 #include "oops/methodOop.hpp"
44 #include "oops/objArrayKlassKlass.hpp"
45 #include "oops/oop.inline.hpp"
46 #include "oops/symbol.hpp"
47 #include "prims/jvmtiExport.hpp"
48 #include "prims/jvmtiRedefineClassesTrace.hpp"
49 #include "runtime/fieldDescriptor.hpp"
50 #include "runtime/handles.inline.hpp"
51 #include "runtime/javaCalls.hpp"
52 #include "runtime/mutexLocker.hpp"
53 #include "services/threadService.hpp"
54 #include "utilities/dtrace.hpp"
55 #ifdef TARGET_OS_FAMILY_linux
56 # include "thread_linux.inline.hpp"
57 #endif
58 #ifdef TARGET_OS_FAMILY_solaris
59 # include "thread_solaris.inline.hpp"
60 #endif
61 #ifdef TARGET_OS_FAMILY_windows
62 # include "thread_windows.inline.hpp"
63 #endif
64 #ifdef TARGET_OS_FAMILY_bsd
65 # include "thread_bsd.inline.hpp"
66 #endif
67 #ifndef SERIALGC
68 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
69 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
70 #include "gc_implementation/g1/g1RemSet.inline.hpp"
71 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
72 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
73 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
74 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
75 #include "oops/oop.pcgc.inline.hpp"
76 #endif
77 #ifdef COMPILER1
78 #include "c1/c1_Compiler.hpp"
79 #endif
81 #ifdef DTRACE_ENABLED
83 #ifndef USDT2
85 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
86 char*, intptr_t, oop, intptr_t);
87 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
88 char*, intptr_t, oop, intptr_t, int);
89 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
90 char*, intptr_t, oop, intptr_t, int);
91 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
92 char*, intptr_t, oop, intptr_t, int);
93 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
94 char*, intptr_t, oop, intptr_t, int);
95 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
96 char*, intptr_t, oop, intptr_t, int);
97 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
98 char*, intptr_t, oop, intptr_t, int);
99 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
100 char*, intptr_t, oop, intptr_t, int);
102 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
103 { \
104 char* data = NULL; \
105 int len = 0; \
106 Symbol* name = (clss)->name(); \
107 if (name != NULL) { \
108 data = (char*)name->bytes(); \
109 len = name->utf8_length(); \
110 } \
111 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \
112 data, len, (clss)->class_loader(), thread_type); \
113 }
115 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
116 { \
117 char* data = NULL; \
118 int len = 0; \
119 Symbol* name = (clss)->name(); \
120 if (name != NULL) { \
121 data = (char*)name->bytes(); \
122 len = name->utf8_length(); \
123 } \
124 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \
125 data, len, (clss)->class_loader(), thread_type, wait); \
126 }
127 #else /* USDT2 */
129 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
130 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
131 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
132 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
133 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
134 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
135 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
136 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
137 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \
138 { \
139 char* data = NULL; \
140 int len = 0; \
141 Symbol* name = (clss)->name(); \
142 if (name != NULL) { \
143 data = (char*)name->bytes(); \
144 len = name->utf8_length(); \
145 } \
146 HOTSPOT_CLASS_INITIALIZATION_##type( \
147 data, len, (clss)->class_loader(), thread_type); \
148 }
150 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
151 { \
152 char* data = NULL; \
153 int len = 0; \
154 Symbol* name = (clss)->name(); \
155 if (name != NULL) { \
156 data = (char*)name->bytes(); \
157 len = name->utf8_length(); \
158 } \
159 HOTSPOT_CLASS_INITIALIZATION_##type( \
160 data, len, (clss)->class_loader(), thread_type, wait); \
161 }
162 #endif /* USDT2 */
164 #else // ndef DTRACE_ENABLED
166 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
167 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
169 #endif // ndef DTRACE_ENABLED
171 bool instanceKlass::should_be_initialized() const {
172 return !is_initialized();
173 }
175 klassVtable* instanceKlass::vtable() const {
176 return new klassVtable(as_klassOop(), start_of_vtable(), vtable_length() / vtableEntry::size());
177 }
179 klassItable* instanceKlass::itable() const {
180 return new klassItable(as_klassOop());
181 }
183 void instanceKlass::eager_initialize(Thread *thread) {
184 if (!EagerInitialization) return;
186 if (this->is_not_initialized()) {
187 // abort if the the class has a class initializer
188 if (this->class_initializer() != NULL) return;
190 // abort if it is java.lang.Object (initialization is handled in genesis)
191 klassOop super = this->super();
192 if (super == NULL) return;
194 // abort if the super class should be initialized
195 if (!instanceKlass::cast(super)->is_initialized()) return;
197 // call body to expose the this pointer
198 instanceKlassHandle this_oop(thread, this->as_klassOop());
199 eager_initialize_impl(this_oop);
200 }
201 }
204 void instanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
205 EXCEPTION_MARK;
206 ObjectLocker ol(this_oop, THREAD);
208 // abort if someone beat us to the initialization
209 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
211 ClassState old_state = this_oop->init_state();
212 link_class_impl(this_oop, true, THREAD);
213 if (HAS_PENDING_EXCEPTION) {
214 CLEAR_PENDING_EXCEPTION;
215 // Abort if linking the class throws an exception.
217 // Use a test to avoid redundantly resetting the state if there's
218 // no change. Set_init_state() asserts that state changes make
219 // progress, whereas here we might just be spinning in place.
220 if( old_state != this_oop->_init_state )
221 this_oop->set_init_state (old_state);
222 } else {
223 // linking successfull, mark class as initialized
224 this_oop->set_init_state (fully_initialized);
225 // trace
226 if (TraceClassInitialization) {
227 ResourceMark rm(THREAD);
228 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
229 }
230 }
231 }
234 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
235 // process. The step comments refers to the procedure described in that section.
236 // Note: implementation moved to static method to expose the this pointer.
237 void instanceKlass::initialize(TRAPS) {
238 if (this->should_be_initialized()) {
239 HandleMark hm(THREAD);
240 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
241 initialize_impl(this_oop, CHECK);
242 // Note: at this point the class may be initialized
243 // OR it may be in the state of being initialized
244 // in case of recursive initialization!
245 } else {
246 assert(is_initialized(), "sanity check");
247 }
248 }
251 bool instanceKlass::verify_code(
252 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
253 // 1) Verify the bytecodes
254 Verifier::Mode mode =
255 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
256 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
257 }
260 // Used exclusively by the shared spaces dump mechanism to prevent
261 // classes mapped into the shared regions in new VMs from appearing linked.
263 void instanceKlass::unlink_class() {
264 assert(is_linked(), "must be linked");
265 _init_state = loaded;
266 }
268 void instanceKlass::link_class(TRAPS) {
269 assert(is_loaded(), "must be loaded");
270 if (!is_linked()) {
271 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
272 link_class_impl(this_oop, true, CHECK);
273 }
274 }
276 // Called to verify that a class can link during initialization, without
277 // throwing a VerifyError.
278 bool instanceKlass::link_class_or_fail(TRAPS) {
279 assert(is_loaded(), "must be loaded");
280 if (!is_linked()) {
281 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
282 link_class_impl(this_oop, false, CHECK_false);
283 }
284 return is_linked();
285 }
287 bool instanceKlass::link_class_impl(
288 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
289 // check for error state
290 if (this_oop->is_in_error_state()) {
291 ResourceMark rm(THREAD);
292 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
293 this_oop->external_name(), false);
294 }
295 // return if already verified
296 if (this_oop->is_linked()) {
297 return true;
298 }
300 // Timing
301 // timer handles recursion
302 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
303 JavaThread* jt = (JavaThread*)THREAD;
305 // link super class before linking this class
306 instanceKlassHandle super(THREAD, this_oop->super());
307 if (super.not_null()) {
308 if (super->is_interface()) { // check if super class is an interface
309 ResourceMark rm(THREAD);
310 Exceptions::fthrow(
311 THREAD_AND_LOCATION,
312 vmSymbols::java_lang_IncompatibleClassChangeError(),
313 "class %s has interface %s as super class",
314 this_oop->external_name(),
315 super->external_name()
316 );
317 return false;
318 }
320 link_class_impl(super, throw_verifyerror, CHECK_false);
321 }
323 // link all interfaces implemented by this class before linking this class
324 objArrayHandle interfaces (THREAD, this_oop->local_interfaces());
325 int num_interfaces = interfaces->length();
326 for (int index = 0; index < num_interfaces; index++) {
327 HandleMark hm(THREAD);
328 instanceKlassHandle ih(THREAD, klassOop(interfaces->obj_at(index)));
329 link_class_impl(ih, throw_verifyerror, CHECK_false);
330 }
332 // in case the class is linked in the process of linking its superclasses
333 if (this_oop->is_linked()) {
334 return true;
335 }
337 // trace only the link time for this klass that includes
338 // the verification time
339 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
340 ClassLoader::perf_class_link_selftime(),
341 ClassLoader::perf_classes_linked(),
342 jt->get_thread_stat()->perf_recursion_counts_addr(),
343 jt->get_thread_stat()->perf_timers_addr(),
344 PerfClassTraceTime::CLASS_LINK);
346 // verification & rewriting
347 {
348 ObjectLocker ol(this_oop, THREAD);
349 // rewritten will have been set if loader constraint error found
350 // on an earlier link attempt
351 // don't verify or rewrite if already rewritten
352 if (!this_oop->is_linked()) {
353 if (!this_oop->is_rewritten()) {
354 {
355 // Timer includes any side effects of class verification (resolution,
356 // etc), but not recursive entry into verify_code().
357 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
358 ClassLoader::perf_class_verify_selftime(),
359 ClassLoader::perf_classes_verified(),
360 jt->get_thread_stat()->perf_recursion_counts_addr(),
361 jt->get_thread_stat()->perf_timers_addr(),
362 PerfClassTraceTime::CLASS_VERIFY);
363 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
364 if (!verify_ok) {
365 return false;
366 }
367 }
369 // Just in case a side-effect of verify linked this class already
370 // (which can sometimes happen since the verifier loads classes
371 // using custom class loaders, which are free to initialize things)
372 if (this_oop->is_linked()) {
373 return true;
374 }
376 // also sets rewritten
377 this_oop->rewrite_class(CHECK_false);
378 }
380 // relocate jsrs and link methods after they are all rewritten
381 this_oop->relocate_and_link_methods(CHECK_false);
383 // Initialize the vtable and interface table after
384 // methods have been rewritten since rewrite may
385 // fabricate new methodOops.
386 // also does loader constraint checking
387 if (!this_oop()->is_shared()) {
388 ResourceMark rm(THREAD);
389 this_oop->vtable()->initialize_vtable(true, CHECK_false);
390 this_oop->itable()->initialize_itable(true, CHECK_false);
391 }
392 #ifdef ASSERT
393 else {
394 ResourceMark rm(THREAD);
395 this_oop->vtable()->verify(tty, true);
396 // In case itable verification is ever added.
397 // this_oop->itable()->verify(tty, true);
398 }
399 #endif
400 this_oop->set_init_state(linked);
401 if (JvmtiExport::should_post_class_prepare()) {
402 Thread *thread = THREAD;
403 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
404 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
405 }
406 }
407 }
408 return true;
409 }
412 // Rewrite the byte codes of all of the methods of a class.
413 // The rewriter must be called exactly once. Rewriting must happen after
414 // verification but before the first method of the class is executed.
415 void instanceKlass::rewrite_class(TRAPS) {
416 assert(is_loaded(), "must be loaded");
417 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
418 if (this_oop->is_rewritten()) {
419 assert(this_oop()->is_shared(), "rewriting an unshared class?");
420 return;
421 }
422 Rewriter::rewrite(this_oop, CHECK);
423 this_oop->set_rewritten();
424 }
426 // Now relocate and link method entry points after class is rewritten.
427 // This is outside is_rewritten flag. In case of an exception, it can be
428 // executed more than once.
429 void instanceKlass::relocate_and_link_methods(TRAPS) {
430 assert(is_loaded(), "must be loaded");
431 instanceKlassHandle this_oop(THREAD, this->as_klassOop());
432 Rewriter::relocate_and_link(this_oop, CHECK);
433 }
436 void instanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
437 // Make sure klass is linked (verified) before initialization
438 // A class could already be verified, since it has been reflected upon.
439 this_oop->link_class(CHECK);
441 DTRACE_CLASSINIT_PROBE(required, instanceKlass::cast(this_oop()), -1);
443 bool wait = false;
445 // refer to the JVM book page 47 for description of steps
446 // Step 1
447 { ObjectLocker ol(this_oop, THREAD);
449 Thread *self = THREAD; // it's passed the current thread
451 // Step 2
452 // If we were to use wait() instead of waitInterruptibly() then
453 // we might end up throwing IE from link/symbol resolution sites
454 // that aren't expected to throw. This would wreak havoc. See 6320309.
455 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
456 wait = true;
457 ol.waitUninterruptibly(CHECK);
458 }
460 // Step 3
461 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
462 DTRACE_CLASSINIT_PROBE_WAIT(recursive, instanceKlass::cast(this_oop()), -1,wait);
463 return;
464 }
466 // Step 4
467 if (this_oop->is_initialized()) {
468 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, instanceKlass::cast(this_oop()), -1,wait);
469 return;
470 }
472 // Step 5
473 if (this_oop->is_in_error_state()) {
474 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, instanceKlass::cast(this_oop()), -1,wait);
475 ResourceMark rm(THREAD);
476 const char* desc = "Could not initialize class ";
477 const char* className = this_oop->external_name();
478 size_t msglen = strlen(desc) + strlen(className) + 1;
479 char* message = NEW_RESOURCE_ARRAY(char, msglen);
480 if (NULL == message) {
481 // Out of memory: can't create detailed error message
482 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
483 } else {
484 jio_snprintf(message, msglen, "%s%s", desc, className);
485 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
486 }
487 }
489 // Step 6
490 this_oop->set_init_state(being_initialized);
491 this_oop->set_init_thread(self);
492 }
494 // Step 7
495 klassOop super_klass = this_oop->super();
496 if (super_klass != NULL && !this_oop->is_interface() && Klass::cast(super_klass)->should_be_initialized()) {
497 Klass::cast(super_klass)->initialize(THREAD);
499 if (HAS_PENDING_EXCEPTION) {
500 Handle e(THREAD, PENDING_EXCEPTION);
501 CLEAR_PENDING_EXCEPTION;
502 {
503 EXCEPTION_MARK;
504 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
505 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below
506 }
507 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, instanceKlass::cast(this_oop()), -1,wait);
508 THROW_OOP(e());
509 }
510 }
512 // Step 8
513 {
514 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
515 JavaThread* jt = (JavaThread*)THREAD;
516 DTRACE_CLASSINIT_PROBE_WAIT(clinit, instanceKlass::cast(this_oop()), -1,wait);
517 // Timer includes any side effects of class initialization (resolution,
518 // etc), but not recursive entry into call_class_initializer().
519 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
520 ClassLoader::perf_class_init_selftime(),
521 ClassLoader::perf_classes_inited(),
522 jt->get_thread_stat()->perf_recursion_counts_addr(),
523 jt->get_thread_stat()->perf_timers_addr(),
524 PerfClassTraceTime::CLASS_CLINIT);
525 this_oop->call_class_initializer(THREAD);
526 }
528 // Step 9
529 if (!HAS_PENDING_EXCEPTION) {
530 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
531 { ResourceMark rm(THREAD);
532 debug_only(this_oop->vtable()->verify(tty, true);)
533 }
534 }
535 else {
536 // Step 10 and 11
537 Handle e(THREAD, PENDING_EXCEPTION);
538 CLEAR_PENDING_EXCEPTION;
539 {
540 EXCEPTION_MARK;
541 this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
542 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
543 }
544 DTRACE_CLASSINIT_PROBE_WAIT(error, instanceKlass::cast(this_oop()), -1,wait);
545 if (e->is_a(SystemDictionary::Error_klass())) {
546 THROW_OOP(e());
547 } else {
548 JavaCallArguments args(e);
549 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
550 vmSymbols::throwable_void_signature(),
551 &args);
552 }
553 }
554 DTRACE_CLASSINIT_PROBE_WAIT(end, instanceKlass::cast(this_oop()), -1,wait);
555 }
558 // Note: implementation moved to static method to expose the this pointer.
559 void instanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
560 instanceKlassHandle kh(THREAD, this->as_klassOop());
561 set_initialization_state_and_notify_impl(kh, state, CHECK);
562 }
564 void instanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
565 ObjectLocker ol(this_oop, THREAD);
566 this_oop->set_init_state(state);
567 ol.notify_all(CHECK);
568 }
570 void instanceKlass::add_implementor(klassOop k) {
571 assert(Compile_lock->owned_by_self(), "");
572 // Filter out my subinterfaces.
573 // (Note: Interfaces are never on the subklass list.)
574 if (instanceKlass::cast(k)->is_interface()) return;
576 // Filter out subclasses whose supers already implement me.
577 // (Note: CHA must walk subclasses of direct implementors
578 // in order to locate indirect implementors.)
579 klassOop sk = instanceKlass::cast(k)->super();
580 if (sk != NULL && instanceKlass::cast(sk)->implements_interface(as_klassOop()))
581 // We only need to check one immediate superclass, since the
582 // implements_interface query looks at transitive_interfaces.
583 // Any supers of the super have the same (or fewer) transitive_interfaces.
584 return;
586 // Update number of implementors
587 int i = _nof_implementors++;
589 // Record this implementor, if there are not too many already
590 if (i < implementors_limit) {
591 assert(_implementors[i] == NULL, "should be exactly one implementor");
592 oop_store_without_check((oop*)&_implementors[i], k);
593 } else if (i == implementors_limit) {
594 // clear out the list on first overflow
595 for (int i2 = 0; i2 < implementors_limit; i2++)
596 oop_store_without_check((oop*)&_implementors[i2], NULL);
597 }
599 // The implementor also implements the transitive_interfaces
600 for (int index = 0; index < local_interfaces()->length(); index++) {
601 instanceKlass::cast(klassOop(local_interfaces()->obj_at(index)))->add_implementor(k);
602 }
603 }
605 void instanceKlass::init_implementor() {
606 for (int i = 0; i < implementors_limit; i++)
607 oop_store_without_check((oop*)&_implementors[i], NULL);
608 _nof_implementors = 0;
609 }
612 void instanceKlass::process_interfaces(Thread *thread) {
613 // link this class into the implementors list of every interface it implements
614 KlassHandle this_as_oop (thread, this->as_klassOop());
615 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
616 assert(local_interfaces()->obj_at(i)->is_klass(), "must be a klass");
617 instanceKlass* interf = instanceKlass::cast(klassOop(local_interfaces()->obj_at(i)));
618 assert(interf->is_interface(), "expected interface");
619 interf->add_implementor(this_as_oop());
620 }
621 }
623 bool instanceKlass::can_be_primary_super_slow() const {
624 if (is_interface())
625 return false;
626 else
627 return Klass::can_be_primary_super_slow();
628 }
630 objArrayOop instanceKlass::compute_secondary_supers(int num_extra_slots, TRAPS) {
631 // The secondaries are the implemented interfaces.
632 instanceKlass* ik = instanceKlass::cast(as_klassOop());
633 objArrayHandle interfaces (THREAD, ik->transitive_interfaces());
634 int num_secondaries = num_extra_slots + interfaces->length();
635 if (num_secondaries == 0) {
636 return Universe::the_empty_system_obj_array();
637 } else if (num_extra_slots == 0) {
638 return interfaces();
639 } else {
640 // a mix of both
641 objArrayOop secondaries = oopFactory::new_system_objArray(num_secondaries, CHECK_NULL);
642 for (int i = 0; i < interfaces->length(); i++) {
643 secondaries->obj_at_put(num_extra_slots+i, interfaces->obj_at(i));
644 }
645 return secondaries;
646 }
647 }
649 bool instanceKlass::compute_is_subtype_of(klassOop k) {
650 if (Klass::cast(k)->is_interface()) {
651 return implements_interface(k);
652 } else {
653 return Klass::compute_is_subtype_of(k);
654 }
655 }
657 bool instanceKlass::implements_interface(klassOop k) const {
658 if (as_klassOop() == k) return true;
659 assert(Klass::cast(k)->is_interface(), "should be an interface class");
660 for (int i = 0; i < transitive_interfaces()->length(); i++) {
661 if (transitive_interfaces()->obj_at(i) == k) {
662 return true;
663 }
664 }
665 return false;
666 }
668 objArrayOop instanceKlass::allocate_objArray(int n, int length, TRAPS) {
669 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
670 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
671 report_java_out_of_memory("Requested array size exceeds VM limit");
672 JvmtiExport::post_array_size_exhausted();
673 THROW_OOP_0(Universe::out_of_memory_error_array_size());
674 }
675 int size = objArrayOopDesc::object_size(length);
676 klassOop ak = array_klass(n, CHECK_NULL);
677 KlassHandle h_ak (THREAD, ak);
678 objArrayOop o =
679 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
680 return o;
681 }
683 instanceOop instanceKlass::register_finalizer(instanceOop i, TRAPS) {
684 if (TraceFinalizerRegistration) {
685 tty->print("Registered ");
686 i->print_value_on(tty);
687 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
688 }
689 instanceHandle h_i(THREAD, i);
690 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
691 JavaValue result(T_VOID);
692 JavaCallArguments args(h_i);
693 methodHandle mh (THREAD, Universe::finalizer_register_method());
694 JavaCalls::call(&result, mh, &args, CHECK_NULL);
695 return h_i();
696 }
698 instanceOop instanceKlass::allocate_instance(TRAPS) {
699 assert(!oop_is_instanceMirror(), "wrong allocation path");
700 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
701 int size = size_helper(); // Query before forming handle.
703 KlassHandle h_k(THREAD, as_klassOop());
705 instanceOop i;
707 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
708 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
709 i = register_finalizer(i, CHECK_NULL);
710 }
711 return i;
712 }
714 instanceOop instanceKlass::allocate_permanent_instance(TRAPS) {
715 // Finalizer registration occurs in the Object.<init> constructor
716 // and constructors normally aren't run when allocating perm
717 // instances so simply disallow finalizable perm objects. This can
718 // be relaxed if a need for it is found.
719 assert(!has_finalizer(), "perm objects not allowed to have finalizers");
720 assert(!oop_is_instanceMirror(), "wrong allocation path");
721 int size = size_helper(); // Query before forming handle.
722 KlassHandle h_k(THREAD, as_klassOop());
723 instanceOop i = (instanceOop)
724 CollectedHeap::permanent_obj_allocate(h_k, size, CHECK_NULL);
725 return i;
726 }
728 void instanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
729 if (is_interface() || is_abstract()) {
730 ResourceMark rm(THREAD);
731 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
732 : vmSymbols::java_lang_InstantiationException(), external_name());
733 }
734 if (as_klassOop() == SystemDictionary::Class_klass()) {
735 ResourceMark rm(THREAD);
736 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
737 : vmSymbols::java_lang_IllegalAccessException(), external_name());
738 }
739 }
741 klassOop instanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
742 instanceKlassHandle this_oop(THREAD, as_klassOop());
743 return array_klass_impl(this_oop, or_null, n, THREAD);
744 }
746 klassOop instanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
747 if (this_oop->array_klasses() == NULL) {
748 if (or_null) return NULL;
750 ResourceMark rm;
751 JavaThread *jt = (JavaThread *)THREAD;
752 {
753 // Atomic creation of array_klasses
754 MutexLocker mc(Compile_lock, THREAD); // for vtables
755 MutexLocker ma(MultiArray_lock, THREAD);
757 // Check if update has already taken place
758 if (this_oop->array_klasses() == NULL) {
759 objArrayKlassKlass* oakk =
760 (objArrayKlassKlass*)Universe::objArrayKlassKlassObj()->klass_part();
762 klassOop k = oakk->allocate_objArray_klass(1, this_oop, CHECK_NULL);
763 this_oop->set_array_klasses(k);
764 }
765 }
766 }
767 // _this will always be set at this point
768 objArrayKlass* oak = (objArrayKlass*)this_oop->array_klasses()->klass_part();
769 if (or_null) {
770 return oak->array_klass_or_null(n);
771 }
772 return oak->array_klass(n, CHECK_NULL);
773 }
775 klassOop instanceKlass::array_klass_impl(bool or_null, TRAPS) {
776 return array_klass_impl(or_null, 1, THREAD);
777 }
779 void instanceKlass::call_class_initializer(TRAPS) {
780 instanceKlassHandle ik (THREAD, as_klassOop());
781 call_class_initializer_impl(ik, THREAD);
782 }
784 static int call_class_initializer_impl_counter = 0; // for debugging
786 methodOop instanceKlass::class_initializer() {
787 methodOop clinit = find_method(
788 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
789 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
790 return clinit;
791 }
792 return NULL;
793 }
795 void instanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
796 methodHandle h_method(THREAD, this_oop->class_initializer());
797 assert(!this_oop->is_initialized(), "we cannot initialize twice");
798 if (TraceClassInitialization) {
799 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
800 this_oop->name()->print_value();
801 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
802 }
803 if (h_method() != NULL) {
804 JavaCallArguments args; // No arguments
805 JavaValue result(T_VOID);
806 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
807 }
808 }
811 void instanceKlass::mask_for(methodHandle method, int bci,
812 InterpreterOopMap* entry_for) {
813 // Dirty read, then double-check under a lock.
814 if (_oop_map_cache == NULL) {
815 // Otherwise, allocate a new one.
816 MutexLocker x(OopMapCacheAlloc_lock);
817 // First time use. Allocate a cache in C heap
818 if (_oop_map_cache == NULL) {
819 _oop_map_cache = new OopMapCache();
820 }
821 }
822 // _oop_map_cache is constant after init; lookup below does is own locking.
823 _oop_map_cache->lookup(method, bci, entry_for);
824 }
827 bool instanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
828 for (JavaFieldStream fs(as_klassOop()); !fs.done(); fs.next()) {
829 Symbol* f_name = fs.name();
830 Symbol* f_sig = fs.signature();
831 if (f_name == name && f_sig == sig) {
832 fd->initialize(as_klassOop(), fs.index());
833 return true;
834 }
835 }
836 return false;
837 }
840 void instanceKlass::shared_symbols_iterate(SymbolClosure* closure) {
841 Klass::shared_symbols_iterate(closure);
842 closure->do_symbol(&_generic_signature);
843 closure->do_symbol(&_source_file_name);
844 closure->do_symbol(&_source_debug_extension);
846 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
847 int name_index = fs.name_index();
848 closure->do_symbol(constants()->symbol_at_addr(name_index));
849 int sig_index = fs.signature_index();
850 closure->do_symbol(constants()->symbol_at_addr(sig_index));
851 }
852 }
855 klassOop instanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
856 const int n = local_interfaces()->length();
857 for (int i = 0; i < n; i++) {
858 klassOop intf1 = klassOop(local_interfaces()->obj_at(i));
859 assert(Klass::cast(intf1)->is_interface(), "just checking type");
860 // search for field in current interface
861 if (instanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
862 assert(fd->is_static(), "interface field must be static");
863 return intf1;
864 }
865 // search for field in direct superinterfaces
866 klassOop intf2 = instanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
867 if (intf2 != NULL) return intf2;
868 }
869 // otherwise field lookup fails
870 return NULL;
871 }
874 klassOop instanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
875 // search order according to newest JVM spec (5.4.3.2, p.167).
876 // 1) search for field in current klass
877 if (find_local_field(name, sig, fd)) {
878 return as_klassOop();
879 }
880 // 2) search for field recursively in direct superinterfaces
881 { klassOop intf = find_interface_field(name, sig, fd);
882 if (intf != NULL) return intf;
883 }
884 // 3) apply field lookup recursively if superclass exists
885 { klassOop supr = super();
886 if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, fd);
887 }
888 // 4) otherwise field lookup fails
889 return NULL;
890 }
893 klassOop instanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
894 // search order according to newest JVM spec (5.4.3.2, p.167).
895 // 1) search for field in current klass
896 if (find_local_field(name, sig, fd)) {
897 if (fd->is_static() == is_static) return as_klassOop();
898 }
899 // 2) search for field recursively in direct superinterfaces
900 if (is_static) {
901 klassOop intf = find_interface_field(name, sig, fd);
902 if (intf != NULL) return intf;
903 }
904 // 3) apply field lookup recursively if superclass exists
905 { klassOop supr = super();
906 if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
907 }
908 // 4) otherwise field lookup fails
909 return NULL;
910 }
913 bool instanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
914 for (JavaFieldStream fs(as_klassOop()); !fs.done(); fs.next()) {
915 if (fs.offset() == offset) {
916 fd->initialize(as_klassOop(), fs.index());
917 if (fd->is_static() == is_static) return true;
918 }
919 }
920 return false;
921 }
924 bool instanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
925 klassOop klass = as_klassOop();
926 while (klass != NULL) {
927 if (instanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
928 return true;
929 }
930 klass = Klass::cast(klass)->super();
931 }
932 return false;
933 }
936 void instanceKlass::methods_do(void f(methodOop method)) {
937 int len = methods()->length();
938 for (int index = 0; index < len; index++) {
939 methodOop m = methodOop(methods()->obj_at(index));
940 assert(m->is_method(), "must be method");
941 f(m);
942 }
943 }
946 void instanceKlass::do_local_static_fields(FieldClosure* cl) {
947 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
948 if (fs.access_flags().is_static()) {
949 fieldDescriptor fd;
950 fd.initialize(as_klassOop(), fs.index());
951 cl->do_field(&fd);
952 }
953 }
954 }
957 void instanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
958 instanceKlassHandle h_this(THREAD, as_klassOop());
959 do_local_static_fields_impl(h_this, f, CHECK);
960 }
963 void instanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
964 for (JavaFieldStream fs(this_oop()); !fs.done(); fs.next()) {
965 if (fs.access_flags().is_static()) {
966 fieldDescriptor fd;
967 fd.initialize(this_oop(), fs.index());
968 f(&fd, CHECK);
969 }
970 }
971 }
974 static int compare_fields_by_offset(int* a, int* b) {
975 return a[0] - b[0];
976 }
978 void instanceKlass::do_nonstatic_fields(FieldClosure* cl) {
979 instanceKlass* super = superklass();
980 if (super != NULL) {
981 super->do_nonstatic_fields(cl);
982 }
983 fieldDescriptor fd;
984 int length = java_fields_count();
985 // In DebugInfo nonstatic fields are sorted by offset.
986 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1));
987 int j = 0;
988 for (int i = 0; i < length; i += 1) {
989 fd.initialize(as_klassOop(), i);
990 if (!fd.is_static()) {
991 fields_sorted[j + 0] = fd.offset();
992 fields_sorted[j + 1] = i;
993 j += 2;
994 }
995 }
996 if (j > 0) {
997 length = j;
998 // _sort_Fn is defined in growableArray.hpp.
999 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1000 for (int i = 0; i < length; i += 2) {
1001 fd.initialize(as_klassOop(), fields_sorted[i + 1]);
1002 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1003 cl->do_field(&fd);
1004 }
1005 }
1006 FREE_C_HEAP_ARRAY(int, fields_sorted);
1007 }
1010 void instanceKlass::array_klasses_do(void f(klassOop k)) {
1011 if (array_klasses() != NULL)
1012 arrayKlass::cast(array_klasses())->array_klasses_do(f);
1013 }
1016 void instanceKlass::with_array_klasses_do(void f(klassOop k)) {
1017 f(as_klassOop());
1018 array_klasses_do(f);
1019 }
1021 #ifdef ASSERT
1022 static int linear_search(objArrayOop methods, Symbol* name, Symbol* signature) {
1023 int len = methods->length();
1024 for (int index = 0; index < len; index++) {
1025 methodOop m = (methodOop)(methods->obj_at(index));
1026 assert(m->is_method(), "must be method");
1027 if (m->signature() == signature && m->name() == name) {
1028 return index;
1029 }
1030 }
1031 return -1;
1032 }
1033 #endif
1035 methodOop instanceKlass::find_method(Symbol* name, Symbol* signature) const {
1036 return instanceKlass::find_method(methods(), name, signature);
1037 }
1039 methodOop instanceKlass::find_method(objArrayOop methods, Symbol* name, Symbol* signature) {
1040 int len = methods->length();
1041 // methods are sorted, so do binary search
1042 int l = 0;
1043 int h = len - 1;
1044 while (l <= h) {
1045 int mid = (l + h) >> 1;
1046 methodOop m = (methodOop)methods->obj_at(mid);
1047 assert(m->is_method(), "must be method");
1048 int res = m->name()->fast_compare(name);
1049 if (res == 0) {
1050 // found matching name; do linear search to find matching signature
1051 // first, quick check for common case
1052 if (m->signature() == signature) return m;
1053 // search downwards through overloaded methods
1054 int i;
1055 for (i = mid - 1; i >= l; i--) {
1056 methodOop m = (methodOop)methods->obj_at(i);
1057 assert(m->is_method(), "must be method");
1058 if (m->name() != name) break;
1059 if (m->signature() == signature) return m;
1060 }
1061 // search upwards
1062 for (i = mid + 1; i <= h; i++) {
1063 methodOop m = (methodOop)methods->obj_at(i);
1064 assert(m->is_method(), "must be method");
1065 if (m->name() != name) break;
1066 if (m->signature() == signature) return m;
1067 }
1068 // not found
1069 #ifdef ASSERT
1070 int index = linear_search(methods, name, signature);
1071 assert(index == -1, err_msg("binary search should have found entry %d", index));
1072 #endif
1073 return NULL;
1074 } else if (res < 0) {
1075 l = mid + 1;
1076 } else {
1077 h = mid - 1;
1078 }
1079 }
1080 #ifdef ASSERT
1081 int index = linear_search(methods, name, signature);
1082 assert(index == -1, err_msg("binary search should have found entry %d", index));
1083 #endif
1084 return NULL;
1085 }
1087 methodOop instanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
1088 klassOop klass = as_klassOop();
1089 while (klass != NULL) {
1090 methodOop method = instanceKlass::cast(klass)->find_method(name, signature);
1091 if (method != NULL) return method;
1092 klass = instanceKlass::cast(klass)->super();
1093 }
1094 return NULL;
1095 }
1097 // lookup a method in all the interfaces that this class implements
1098 methodOop instanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1099 Symbol* signature) const {
1100 objArrayOop all_ifs = instanceKlass::cast(as_klassOop())->transitive_interfaces();
1101 int num_ifs = all_ifs->length();
1102 instanceKlass *ik = NULL;
1103 for (int i = 0; i < num_ifs; i++) {
1104 ik = instanceKlass::cast(klassOop(all_ifs->obj_at(i)));
1105 methodOop m = ik->lookup_method(name, signature);
1106 if (m != NULL) {
1107 return m;
1108 }
1109 }
1110 return NULL;
1111 }
1113 /* jni_id_for_impl for jfieldIds only */
1114 JNIid* instanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1115 MutexLocker ml(JfieldIdCreation_lock);
1116 // Retry lookup after we got the lock
1117 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1118 if (probe == NULL) {
1119 // Slow case, allocate new static field identifier
1120 probe = new JNIid(this_oop->as_klassOop(), offset, this_oop->jni_ids());
1121 this_oop->set_jni_ids(probe);
1122 }
1123 return probe;
1124 }
1127 /* jni_id_for for jfieldIds only */
1128 JNIid* instanceKlass::jni_id_for(int offset) {
1129 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1130 if (probe == NULL) {
1131 probe = jni_id_for_impl(this->as_klassOop(), offset);
1132 }
1133 return probe;
1134 }
1136 u2 instanceKlass::enclosing_method_data(int offset) {
1137 typeArrayOop inner_class_list = inner_classes();
1138 if (inner_class_list == NULL) {
1139 return 0;
1140 }
1141 int length = inner_class_list->length();
1142 if (length % inner_class_next_offset == 0) {
1143 return 0;
1144 } else {
1145 int index = length - enclosing_method_attribute_size;
1146 typeArrayHandle inner_class_list_h(inner_class_list);
1147 assert(offset < enclosing_method_attribute_size, "invalid offset");
1148 return inner_class_list_h->ushort_at(index + offset);
1149 }
1150 }
1152 void instanceKlass::set_enclosing_method_indices(u2 class_index,
1153 u2 method_index) {
1154 typeArrayOop inner_class_list = inner_classes();
1155 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1156 int length = inner_class_list->length();
1157 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1158 int index = length - enclosing_method_attribute_size;
1159 typeArrayHandle inner_class_list_h(inner_class_list);
1160 inner_class_list_h->ushort_at_put(
1161 index + enclosing_method_class_index_offset, class_index);
1162 inner_class_list_h->ushort_at_put(
1163 index + enclosing_method_method_index_offset, method_index);
1164 }
1165 }
1167 // Lookup or create a jmethodID.
1168 // This code is called by the VMThread and JavaThreads so the
1169 // locking has to be done very carefully to avoid deadlocks
1170 // and/or other cache consistency problems.
1171 //
1172 jmethodID instanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1173 size_t idnum = (size_t)method_h->method_idnum();
1174 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1175 size_t length = 0;
1176 jmethodID id = NULL;
1178 // We use a double-check locking idiom here because this cache is
1179 // performance sensitive. In the normal system, this cache only
1180 // transitions from NULL to non-NULL which is safe because we use
1181 // release_set_methods_jmethod_ids() to advertise the new cache.
1182 // A partially constructed cache should never be seen by a racing
1183 // thread. We also use release_store_ptr() to save a new jmethodID
1184 // in the cache so a partially constructed jmethodID should never be
1185 // seen either. Cache reads of existing jmethodIDs proceed without a
1186 // lock, but cache writes of a new jmethodID requires uniqueness and
1187 // creation of the cache itself requires no leaks so a lock is
1188 // generally acquired in those two cases.
1189 //
1190 // If the RedefineClasses() API has been used, then this cache can
1191 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1192 // Cache creation requires no leaks and we require safety between all
1193 // cache accesses and freeing of the old cache so a lock is generally
1194 // acquired when the RedefineClasses() API has been used.
1196 if (jmeths != NULL) {
1197 // the cache already exists
1198 if (!ik_h->idnum_can_increment()) {
1199 // the cache can't grow so we can just get the current values
1200 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1201 } else {
1202 // cache can grow so we have to be more careful
1203 if (Threads::number_of_threads() == 0 ||
1204 SafepointSynchronize::is_at_safepoint()) {
1205 // we're single threaded or at a safepoint - no locking needed
1206 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1207 } else {
1208 MutexLocker ml(JmethodIdCreation_lock);
1209 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1210 }
1211 }
1212 }
1213 // implied else:
1214 // we need to allocate a cache so default length and id values are good
1216 if (jmeths == NULL || // no cache yet
1217 length <= idnum || // cache is too short
1218 id == NULL) { // cache doesn't contain entry
1220 // This function can be called by the VMThread so we have to do all
1221 // things that might block on a safepoint before grabbing the lock.
1222 // Otherwise, we can deadlock with the VMThread or have a cache
1223 // consistency issue. These vars keep track of what we might have
1224 // to free after the lock is dropped.
1225 jmethodID to_dealloc_id = NULL;
1226 jmethodID* to_dealloc_jmeths = NULL;
1228 // may not allocate new_jmeths or use it if we allocate it
1229 jmethodID* new_jmeths = NULL;
1230 if (length <= idnum) {
1231 // allocate a new cache that might be used
1232 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1233 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1);
1234 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1235 // cache size is stored in element[0], other elements offset by one
1236 new_jmeths[0] = (jmethodID)size;
1237 }
1239 // allocate a new jmethodID that might be used
1240 jmethodID new_id = NULL;
1241 if (method_h->is_old() && !method_h->is_obsolete()) {
1242 // The method passed in is old (but not obsolete), we need to use the current version
1243 methodOop current_method = ik_h->method_with_idnum((int)idnum);
1244 assert(current_method != NULL, "old and but not obsolete, so should exist");
1245 methodHandle current_method_h(current_method == NULL? method_h() : current_method);
1246 new_id = JNIHandles::make_jmethod_id(current_method_h);
1247 } else {
1248 // It is the current version of the method or an obsolete method,
1249 // use the version passed in
1250 new_id = JNIHandles::make_jmethod_id(method_h);
1251 }
1253 if (Threads::number_of_threads() == 0 ||
1254 SafepointSynchronize::is_at_safepoint()) {
1255 // we're single threaded or at a safepoint - no locking needed
1256 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1257 &to_dealloc_id, &to_dealloc_jmeths);
1258 } else {
1259 MutexLocker ml(JmethodIdCreation_lock);
1260 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1261 &to_dealloc_id, &to_dealloc_jmeths);
1262 }
1264 // The lock has been dropped so we can free resources.
1265 // Free up either the old cache or the new cache if we allocated one.
1266 if (to_dealloc_jmeths != NULL) {
1267 FreeHeap(to_dealloc_jmeths);
1268 }
1269 // free up the new ID since it wasn't needed
1270 if (to_dealloc_id != NULL) {
1271 JNIHandles::destroy_jmethod_id(to_dealloc_id);
1272 }
1273 }
1274 return id;
1275 }
1278 // Common code to fetch the jmethodID from the cache or update the
1279 // cache with the new jmethodID. This function should never do anything
1280 // that causes the caller to go to a safepoint or we can deadlock with
1281 // the VMThread or have cache consistency issues.
1282 //
1283 jmethodID instanceKlass::get_jmethod_id_fetch_or_update(
1284 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1285 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1286 jmethodID** to_dealloc_jmeths_p) {
1287 assert(new_id != NULL, "sanity check");
1288 assert(to_dealloc_id_p != NULL, "sanity check");
1289 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1290 assert(Threads::number_of_threads() == 0 ||
1291 SafepointSynchronize::is_at_safepoint() ||
1292 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1294 // reacquire the cache - we are locked, single threaded or at a safepoint
1295 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1296 jmethodID id = NULL;
1297 size_t length = 0;
1299 if (jmeths == NULL || // no cache yet
1300 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1301 if (jmeths != NULL) {
1302 // copy any existing entries from the old cache
1303 for (size_t index = 0; index < length; index++) {
1304 new_jmeths[index+1] = jmeths[index+1];
1305 }
1306 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1307 }
1308 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1309 } else {
1310 // fetch jmethodID (if any) from the existing cache
1311 id = jmeths[idnum+1];
1312 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1313 }
1314 if (id == NULL) {
1315 // No matching jmethodID in the existing cache or we have a new
1316 // cache or we just grew the cache. This cache write is done here
1317 // by the first thread to win the foot race because a jmethodID
1318 // needs to be unique once it is generally available.
1319 id = new_id;
1321 // The jmethodID cache can be read while unlocked so we have to
1322 // make sure the new jmethodID is complete before installing it
1323 // in the cache.
1324 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1325 } else {
1326 *to_dealloc_id_p = new_id; // save new id for later delete
1327 }
1328 return id;
1329 }
1332 // Common code to get the jmethodID cache length and the jmethodID
1333 // value at index idnum if there is one.
1334 //
1335 void instanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1336 size_t idnum, size_t *length_p, jmethodID* id_p) {
1337 assert(cache != NULL, "sanity check");
1338 assert(length_p != NULL, "sanity check");
1339 assert(id_p != NULL, "sanity check");
1341 // cache size is stored in element[0], other elements offset by one
1342 *length_p = (size_t)cache[0];
1343 if (*length_p <= idnum) { // cache is too short
1344 *id_p = NULL;
1345 } else {
1346 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1347 }
1348 }
1351 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1352 jmethodID instanceKlass::jmethod_id_or_null(methodOop method) {
1353 size_t idnum = (size_t)method->method_idnum();
1354 jmethodID* jmeths = methods_jmethod_ids_acquire();
1355 size_t length; // length assigned as debugging crumb
1356 jmethodID id = NULL;
1357 if (jmeths != NULL && // If there is a cache
1358 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1359 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1360 }
1361 return id;
1362 }
1365 // Cache an itable index
1366 void instanceKlass::set_cached_itable_index(size_t idnum, int index) {
1367 int* indices = methods_cached_itable_indices_acquire();
1368 int* to_dealloc_indices = NULL;
1370 // We use a double-check locking idiom here because this cache is
1371 // performance sensitive. In the normal system, this cache only
1372 // transitions from NULL to non-NULL which is safe because we use
1373 // release_set_methods_cached_itable_indices() to advertise the
1374 // new cache. A partially constructed cache should never be seen
1375 // by a racing thread. Cache reads and writes proceed without a
1376 // lock, but creation of the cache itself requires no leaks so a
1377 // lock is generally acquired in that case.
1378 //
1379 // If the RedefineClasses() API has been used, then this cache can
1380 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1381 // Cache creation requires no leaks and we require safety between all
1382 // cache accesses and freeing of the old cache so a lock is generally
1383 // acquired when the RedefineClasses() API has been used.
1385 if (indices == NULL || idnum_can_increment()) {
1386 // we need a cache or the cache can grow
1387 MutexLocker ml(JNICachedItableIndex_lock);
1388 // reacquire the cache to see if another thread already did the work
1389 indices = methods_cached_itable_indices_acquire();
1390 size_t length = 0;
1391 // cache size is stored in element[0], other elements offset by one
1392 if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
1393 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1394 int* new_indices = NEW_C_HEAP_ARRAY(int, size+1);
1395 new_indices[0] = (int)size;
1396 // copy any existing entries
1397 size_t i;
1398 for (i = 0; i < length; i++) {
1399 new_indices[i+1] = indices[i+1];
1400 }
1401 // Set all the rest to -1
1402 for (i = length; i < size; i++) {
1403 new_indices[i+1] = -1;
1404 }
1405 if (indices != NULL) {
1406 // We have an old cache to delete so save it for after we
1407 // drop the lock.
1408 to_dealloc_indices = indices;
1409 }
1410 release_set_methods_cached_itable_indices(indices = new_indices);
1411 }
1413 if (idnum_can_increment()) {
1414 // this cache can grow so we have to write to it safely
1415 indices[idnum+1] = index;
1416 }
1417 } else {
1418 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
1419 }
1421 if (!idnum_can_increment()) {
1422 // The cache cannot grow and this JNI itable index value does not
1423 // have to be unique like a jmethodID. If there is a race to set it,
1424 // it doesn't matter.
1425 indices[idnum+1] = index;
1426 }
1428 if (to_dealloc_indices != NULL) {
1429 // we allocated a new cache so free the old one
1430 FreeHeap(to_dealloc_indices);
1431 }
1432 }
1435 // Retrieve a cached itable index
1436 int instanceKlass::cached_itable_index(size_t idnum) {
1437 int* indices = methods_cached_itable_indices_acquire();
1438 if (indices != NULL && ((size_t)indices[0]) > idnum) {
1439 // indices exist and are long enough, retrieve possible cached
1440 return indices[idnum+1];
1441 }
1442 return -1;
1443 }
1446 //
1447 // Walk the list of dependent nmethods searching for nmethods which
1448 // are dependent on the changes that were passed in and mark them for
1449 // deoptimization. Returns the number of nmethods found.
1450 //
1451 int instanceKlass::mark_dependent_nmethods(DepChange& changes) {
1452 assert_locked_or_safepoint(CodeCache_lock);
1453 int found = 0;
1454 nmethodBucket* b = _dependencies;
1455 while (b != NULL) {
1456 nmethod* nm = b->get_nmethod();
1457 // since dependencies aren't removed until an nmethod becomes a zombie,
1458 // the dependency list may contain nmethods which aren't alive.
1459 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1460 if (TraceDependencies) {
1461 ResourceMark rm;
1462 tty->print_cr("Marked for deoptimization");
1463 tty->print_cr(" context = %s", this->external_name());
1464 changes.print();
1465 nm->print();
1466 nm->print_dependencies();
1467 }
1468 nm->mark_for_deoptimization();
1469 found++;
1470 }
1471 b = b->next();
1472 }
1473 return found;
1474 }
1477 //
1478 // Add an nmethodBucket to the list of dependencies for this nmethod.
1479 // It's possible that an nmethod has multiple dependencies on this klass
1480 // so a count is kept for each bucket to guarantee that creation and
1481 // deletion of dependencies is consistent.
1482 //
1483 void instanceKlass::add_dependent_nmethod(nmethod* nm) {
1484 assert_locked_or_safepoint(CodeCache_lock);
1485 nmethodBucket* b = _dependencies;
1486 nmethodBucket* last = NULL;
1487 while (b != NULL) {
1488 if (nm == b->get_nmethod()) {
1489 b->increment();
1490 return;
1491 }
1492 b = b->next();
1493 }
1494 _dependencies = new nmethodBucket(nm, _dependencies);
1495 }
1498 //
1499 // Decrement count of the nmethod in the dependency list and remove
1500 // the bucket competely when the count goes to 0. This method must
1501 // find a corresponding bucket otherwise there's a bug in the
1502 // recording of dependecies.
1503 //
1504 void instanceKlass::remove_dependent_nmethod(nmethod* nm) {
1505 assert_locked_or_safepoint(CodeCache_lock);
1506 nmethodBucket* b = _dependencies;
1507 nmethodBucket* last = NULL;
1508 while (b != NULL) {
1509 if (nm == b->get_nmethod()) {
1510 if (b->decrement() == 0) {
1511 if (last == NULL) {
1512 _dependencies = b->next();
1513 } else {
1514 last->set_next(b->next());
1515 }
1516 delete b;
1517 }
1518 return;
1519 }
1520 last = b;
1521 b = b->next();
1522 }
1523 #ifdef ASSERT
1524 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1525 nm->print();
1526 #endif // ASSERT
1527 ShouldNotReachHere();
1528 }
1531 #ifndef PRODUCT
1532 void instanceKlass::print_dependent_nmethods(bool verbose) {
1533 nmethodBucket* b = _dependencies;
1534 int idx = 0;
1535 while (b != NULL) {
1536 nmethod* nm = b->get_nmethod();
1537 tty->print("[%d] count=%d { ", idx++, b->count());
1538 if (!verbose) {
1539 nm->print_on(tty, "nmethod");
1540 tty->print_cr(" } ");
1541 } else {
1542 nm->print();
1543 nm->print_dependencies();
1544 tty->print_cr("--- } ");
1545 }
1546 b = b->next();
1547 }
1548 }
1551 bool instanceKlass::is_dependent_nmethod(nmethod* nm) {
1552 nmethodBucket* b = _dependencies;
1553 while (b != NULL) {
1554 if (nm == b->get_nmethod()) {
1555 return true;
1556 }
1557 b = b->next();
1558 }
1559 return false;
1560 }
1561 #endif //PRODUCT
1564 #ifdef ASSERT
1565 template <class T> void assert_is_in(T *p) {
1566 T heap_oop = oopDesc::load_heap_oop(p);
1567 if (!oopDesc::is_null(heap_oop)) {
1568 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1569 assert(Universe::heap()->is_in(o), "should be in heap");
1570 }
1571 }
1572 template <class T> void assert_is_in_closed_subset(T *p) {
1573 T heap_oop = oopDesc::load_heap_oop(p);
1574 if (!oopDesc::is_null(heap_oop)) {
1575 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1576 assert(Universe::heap()->is_in_closed_subset(o), "should be in closed");
1577 }
1578 }
1579 template <class T> void assert_is_in_reserved(T *p) {
1580 T heap_oop = oopDesc::load_heap_oop(p);
1581 if (!oopDesc::is_null(heap_oop)) {
1582 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1583 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1584 }
1585 }
1586 template <class T> void assert_nothing(T *p) {}
1588 #else
1589 template <class T> void assert_is_in(T *p) {}
1590 template <class T> void assert_is_in_closed_subset(T *p) {}
1591 template <class T> void assert_is_in_reserved(T *p) {}
1592 template <class T> void assert_nothing(T *p) {}
1593 #endif // ASSERT
1595 //
1596 // Macros that iterate over areas of oops which are specialized on type of
1597 // oop pointer either narrow or wide, depending on UseCompressedOops
1598 //
1599 // Parameters are:
1600 // T - type of oop to point to (either oop or narrowOop)
1601 // start_p - starting pointer for region to iterate over
1602 // count - number of oops or narrowOops to iterate over
1603 // do_oop - action to perform on each oop (it's arbitrary C code which
1604 // makes it more efficient to put in a macro rather than making
1605 // it a template function)
1606 // assert_fn - assert function which is template function because performance
1607 // doesn't matter when enabled.
1608 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1609 T, start_p, count, do_oop, \
1610 assert_fn) \
1611 { \
1612 T* p = (T*)(start_p); \
1613 T* const end = p + (count); \
1614 while (p < end) { \
1615 (assert_fn)(p); \
1616 do_oop; \
1617 ++p; \
1618 } \
1619 }
1621 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1622 T, start_p, count, do_oop, \
1623 assert_fn) \
1624 { \
1625 T* const start = (T*)(start_p); \
1626 T* p = start + (count); \
1627 while (start < p) { \
1628 --p; \
1629 (assert_fn)(p); \
1630 do_oop; \
1631 } \
1632 }
1634 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
1635 T, start_p, count, low, high, \
1636 do_oop, assert_fn) \
1637 { \
1638 T* const l = (T*)(low); \
1639 T* const h = (T*)(high); \
1640 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
1641 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
1642 "bounded region must be properly aligned"); \
1643 T* p = (T*)(start_p); \
1644 T* end = p + (count); \
1645 if (p < l) p = l; \
1646 if (end > h) end = h; \
1647 while (p < end) { \
1648 (assert_fn)(p); \
1649 do_oop; \
1650 ++p; \
1651 } \
1652 }
1655 // The following macros call specialized macros, passing either oop or
1656 // narrowOop as the specialization type. These test the UseCompressedOops
1657 // flag.
1658 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
1659 { \
1660 /* Compute oopmap block range. The common case \
1661 is nonstatic_oop_map_size == 1. */ \
1662 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1663 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
1664 if (UseCompressedOops) { \
1665 while (map < end_map) { \
1666 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
1667 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1668 do_oop, assert_fn) \
1669 ++map; \
1670 } \
1671 } else { \
1672 while (map < end_map) { \
1673 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
1674 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1675 do_oop, assert_fn) \
1676 ++map; \
1677 } \
1678 } \
1679 }
1681 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
1682 { \
1683 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
1684 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
1685 if (UseCompressedOops) { \
1686 while (start_map < map) { \
1687 --map; \
1688 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
1689 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1690 do_oop, assert_fn) \
1691 } \
1692 } else { \
1693 while (start_map < map) { \
1694 --map; \
1695 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
1696 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1697 do_oop, assert_fn) \
1698 } \
1699 } \
1700 }
1702 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
1703 assert_fn) \
1704 { \
1705 /* Compute oopmap block range. The common case is \
1706 nonstatic_oop_map_size == 1, so we accept the \
1707 usually non-existent extra overhead of examining \
1708 all the maps. */ \
1709 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1710 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
1711 if (UseCompressedOops) { \
1712 while (map < end_map) { \
1713 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
1714 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1715 low, high, \
1716 do_oop, assert_fn) \
1717 ++map; \
1718 } \
1719 } else { \
1720 while (map < end_map) { \
1721 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
1722 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1723 low, high, \
1724 do_oop, assert_fn) \
1725 ++map; \
1726 } \
1727 } \
1728 }
1730 void instanceKlass::oop_follow_contents(oop obj) {
1731 assert(obj != NULL, "can't follow the content of NULL object");
1732 obj->follow_header();
1733 InstanceKlass_OOP_MAP_ITERATE( \
1734 obj, \
1735 MarkSweep::mark_and_push(p), \
1736 assert_is_in_closed_subset)
1737 }
1739 #ifndef SERIALGC
1740 void instanceKlass::oop_follow_contents(ParCompactionManager* cm,
1741 oop obj) {
1742 assert(obj != NULL, "can't follow the content of NULL object");
1743 obj->follow_header(cm);
1744 InstanceKlass_OOP_MAP_ITERATE( \
1745 obj, \
1746 PSParallelCompact::mark_and_push(cm, p), \
1747 assert_is_in)
1748 }
1749 #endif // SERIALGC
1751 // closure's do_header() method dicates whether the given closure should be
1752 // applied to the klass ptr in the object header.
1754 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
1755 \
1756 int instanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
1757 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
1758 /* header */ \
1759 if (closure->do_header()) { \
1760 obj->oop_iterate_header(closure); \
1761 } \
1762 InstanceKlass_OOP_MAP_ITERATE( \
1763 obj, \
1764 SpecializationStats:: \
1765 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
1766 (closure)->do_oop##nv_suffix(p), \
1767 assert_is_in_closed_subset) \
1768 return size_helper(); \
1769 }
1771 #ifndef SERIALGC
1772 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
1773 \
1774 int instanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
1775 OopClosureType* closure) { \
1776 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
1777 /* header */ \
1778 if (closure->do_header()) { \
1779 obj->oop_iterate_header(closure); \
1780 } \
1781 /* instance variables */ \
1782 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
1783 obj, \
1784 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
1785 (closure)->do_oop##nv_suffix(p), \
1786 assert_is_in_closed_subset) \
1787 return size_helper(); \
1788 }
1789 #endif // !SERIALGC
1791 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
1792 \
1793 int instanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
1794 OopClosureType* closure, \
1795 MemRegion mr) { \
1796 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
1797 if (closure->do_header()) { \
1798 obj->oop_iterate_header(closure, mr); \
1799 } \
1800 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
1801 obj, mr.start(), mr.end(), \
1802 (closure)->do_oop##nv_suffix(p), \
1803 assert_is_in_closed_subset) \
1804 return size_helper(); \
1805 }
1807 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
1808 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
1809 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
1810 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
1811 #ifndef SERIALGC
1812 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
1813 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
1814 #endif // !SERIALGC
1816 int instanceKlass::oop_adjust_pointers(oop obj) {
1817 int size = size_helper();
1818 InstanceKlass_OOP_MAP_ITERATE( \
1819 obj, \
1820 MarkSweep::adjust_pointer(p), \
1821 assert_is_in)
1822 obj->adjust_header();
1823 return size;
1824 }
1826 #ifndef SERIALGC
1827 void instanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
1828 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
1829 obj, \
1830 if (PSScavenge::should_scavenge(p)) { \
1831 pm->claim_or_forward_depth(p); \
1832 }, \
1833 assert_nothing )
1834 }
1836 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
1837 InstanceKlass_OOP_MAP_ITERATE( \
1838 obj, \
1839 PSParallelCompact::adjust_pointer(p), \
1840 assert_nothing)
1841 return size_helper();
1842 }
1844 #endif // SERIALGC
1846 // This klass is alive but the implementor link is not followed/updated.
1847 // Subklass and sibling links are handled by Klass::follow_weak_klass_links
1849 void instanceKlass::follow_weak_klass_links(
1850 BoolObjectClosure* is_alive, OopClosure* keep_alive) {
1851 assert(is_alive->do_object_b(as_klassOop()), "this oop should be live");
1852 if (ClassUnloading) {
1853 for (int i = 0; i < implementors_limit; i++) {
1854 klassOop impl = _implementors[i];
1855 if (impl == NULL) break; // no more in the list
1856 if (!is_alive->do_object_b(impl)) {
1857 // remove this guy from the list by overwriting him with the tail
1858 int lasti = --_nof_implementors;
1859 assert(lasti >= i && lasti < implementors_limit, "just checking");
1860 _implementors[i] = _implementors[lasti];
1861 _implementors[lasti] = NULL;
1862 --i; // rerun the loop at this index
1863 }
1864 }
1865 } else {
1866 for (int i = 0; i < implementors_limit; i++) {
1867 keep_alive->do_oop(&adr_implementors()[i]);
1868 }
1869 }
1870 Klass::follow_weak_klass_links(is_alive, keep_alive);
1871 }
1873 void instanceKlass::remove_unshareable_info() {
1874 Klass::remove_unshareable_info();
1875 init_implementor();
1876 }
1878 static void clear_all_breakpoints(methodOop m) {
1879 m->clear_all_breakpoints();
1880 }
1882 void instanceKlass::release_C_heap_structures() {
1883 // Deallocate oop map cache
1884 if (_oop_map_cache != NULL) {
1885 delete _oop_map_cache;
1886 _oop_map_cache = NULL;
1887 }
1889 // Deallocate JNI identifiers for jfieldIDs
1890 JNIid::deallocate(jni_ids());
1891 set_jni_ids(NULL);
1893 jmethodID* jmeths = methods_jmethod_ids_acquire();
1894 if (jmeths != (jmethodID*)NULL) {
1895 release_set_methods_jmethod_ids(NULL);
1896 FreeHeap(jmeths);
1897 }
1899 int* indices = methods_cached_itable_indices_acquire();
1900 if (indices != (int*)NULL) {
1901 release_set_methods_cached_itable_indices(NULL);
1902 FreeHeap(indices);
1903 }
1905 // release dependencies
1906 nmethodBucket* b = _dependencies;
1907 _dependencies = NULL;
1908 while (b != NULL) {
1909 nmethodBucket* next = b->next();
1910 delete b;
1911 b = next;
1912 }
1914 // Deallocate breakpoint records
1915 if (breakpoints() != 0x0) {
1916 methods_do(clear_all_breakpoints);
1917 assert(breakpoints() == 0x0, "should have cleared breakpoints");
1918 }
1920 // deallocate information about previous versions
1921 if (_previous_versions != NULL) {
1922 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
1923 PreviousVersionNode * pv_node = _previous_versions->at(i);
1924 delete pv_node;
1925 }
1926 delete _previous_versions;
1927 _previous_versions = NULL;
1928 }
1930 // deallocate the cached class file
1931 if (_cached_class_file_bytes != NULL) {
1932 os::free(_cached_class_file_bytes);
1933 _cached_class_file_bytes = NULL;
1934 _cached_class_file_len = 0;
1935 }
1937 // Decrement symbol reference counts associated with the unloaded class.
1938 if (_name != NULL) _name->decrement_refcount();
1939 // unreference array name derived from this class name (arrays of an unloaded
1940 // class can't be referenced anymore).
1941 if (_array_name != NULL) _array_name->decrement_refcount();
1942 if (_source_file_name != NULL) _source_file_name->decrement_refcount();
1943 if (_source_debug_extension != NULL) _source_debug_extension->decrement_refcount();
1944 // walk constant pool and decrement symbol reference counts
1945 _constants->unreference_symbols();
1946 }
1948 void instanceKlass::set_source_file_name(Symbol* n) {
1949 _source_file_name = n;
1950 if (_source_file_name != NULL) _source_file_name->increment_refcount();
1951 }
1953 void instanceKlass::set_source_debug_extension(Symbol* n) {
1954 _source_debug_extension = n;
1955 if (_source_debug_extension != NULL) _source_debug_extension->increment_refcount();
1956 }
1958 address instanceKlass::static_field_addr(int offset) {
1959 return (address)(offset + instanceMirrorKlass::offset_of_static_fields() + (intptr_t)java_mirror());
1960 }
1963 const char* instanceKlass::signature_name() const {
1964 const char* src = (const char*) (name()->as_C_string());
1965 const int src_length = (int)strlen(src);
1966 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
1967 int src_index = 0;
1968 int dest_index = 0;
1969 dest[dest_index++] = 'L';
1970 while (src_index < src_length) {
1971 dest[dest_index++] = src[src_index++];
1972 }
1973 dest[dest_index++] = ';';
1974 dest[dest_index] = '\0';
1975 return dest;
1976 }
1978 // different verisons of is_same_class_package
1979 bool instanceKlass::is_same_class_package(klassOop class2) {
1980 klassOop class1 = as_klassOop();
1981 oop classloader1 = instanceKlass::cast(class1)->class_loader();
1982 Symbol* classname1 = Klass::cast(class1)->name();
1984 if (Klass::cast(class2)->oop_is_objArray()) {
1985 class2 = objArrayKlass::cast(class2)->bottom_klass();
1986 }
1987 oop classloader2;
1988 if (Klass::cast(class2)->oop_is_instance()) {
1989 classloader2 = instanceKlass::cast(class2)->class_loader();
1990 } else {
1991 assert(Klass::cast(class2)->oop_is_typeArray(), "should be type array");
1992 classloader2 = NULL;
1993 }
1994 Symbol* classname2 = Klass::cast(class2)->name();
1996 return instanceKlass::is_same_class_package(classloader1, classname1,
1997 classloader2, classname2);
1998 }
2000 bool instanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2001 klassOop class1 = as_klassOop();
2002 oop classloader1 = instanceKlass::cast(class1)->class_loader();
2003 Symbol* classname1 = Klass::cast(class1)->name();
2005 return instanceKlass::is_same_class_package(classloader1, classname1,
2006 classloader2, classname2);
2007 }
2009 // return true if two classes are in the same package, classloader
2010 // and classname information is enough to determine a class's package
2011 bool instanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2012 oop class_loader2, Symbol* class_name2) {
2013 if (class_loader1 != class_loader2) {
2014 return false;
2015 } else if (class_name1 == class_name2) {
2016 return true; // skip painful bytewise comparison
2017 } else {
2018 ResourceMark rm;
2020 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2021 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2022 // Otherwise, we just compare jbyte values between the strings.
2023 const jbyte *name1 = class_name1->base();
2024 const jbyte *name2 = class_name2->base();
2026 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2027 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2029 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2030 // One of the two doesn't have a package. Only return true
2031 // if the other one also doesn't have a package.
2032 return last_slash1 == last_slash2;
2033 } else {
2034 // Skip over '['s
2035 if (*name1 == '[') {
2036 do {
2037 name1++;
2038 } while (*name1 == '[');
2039 if (*name1 != 'L') {
2040 // Something is terribly wrong. Shouldn't be here.
2041 return false;
2042 }
2043 }
2044 if (*name2 == '[') {
2045 do {
2046 name2++;
2047 } while (*name2 == '[');
2048 if (*name2 != 'L') {
2049 // Something is terribly wrong. Shouldn't be here.
2050 return false;
2051 }
2052 }
2054 // Check that package part is identical
2055 int length1 = last_slash1 - name1;
2056 int length2 = last_slash2 - name2;
2058 return UTF8::equal(name1, length1, name2, length2);
2059 }
2060 }
2061 }
2063 // Returns true iff super_method can be overridden by a method in targetclassname
2064 // See JSL 3rd edition 8.4.6.1
2065 // Assumes name-signature match
2066 // "this" is instanceKlass of super_method which must exist
2067 // note that the instanceKlass of the method in the targetclassname has not always been created yet
2068 bool instanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2069 // Private methods can not be overridden
2070 if (super_method->is_private()) {
2071 return false;
2072 }
2073 // If super method is accessible, then override
2074 if ((super_method->is_protected()) ||
2075 (super_method->is_public())) {
2076 return true;
2077 }
2078 // Package-private methods are not inherited outside of package
2079 assert(super_method->is_package_private(), "must be package private");
2080 return(is_same_class_package(targetclassloader(), targetclassname));
2081 }
2083 /* defined for now in jvm.cpp, for historical reasons *--
2084 klassOop instanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2085 Symbol*& simple_name_result, TRAPS) {
2086 ...
2087 }
2088 */
2090 // tell if two classes have the same enclosing class (at package level)
2091 bool instanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2092 klassOop class2_oop, TRAPS) {
2093 if (class2_oop == class1->as_klassOop()) return true;
2094 if (!Klass::cast(class2_oop)->oop_is_instance()) return false;
2095 instanceKlassHandle class2(THREAD, class2_oop);
2097 // must be in same package before we try anything else
2098 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2099 return false;
2101 // As long as there is an outer1.getEnclosingClass,
2102 // shift the search outward.
2103 instanceKlassHandle outer1 = class1;
2104 for (;;) {
2105 // As we walk along, look for equalities between outer1 and class2.
2106 // Eventually, the walks will terminate as outer1 stops
2107 // at the top-level class around the original class.
2108 bool ignore_inner_is_member;
2109 klassOop next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2110 CHECK_false);
2111 if (next == NULL) break;
2112 if (next == class2()) return true;
2113 outer1 = instanceKlassHandle(THREAD, next);
2114 }
2116 // Now do the same for class2.
2117 instanceKlassHandle outer2 = class2;
2118 for (;;) {
2119 bool ignore_inner_is_member;
2120 klassOop next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2121 CHECK_false);
2122 if (next == NULL) break;
2123 // Might as well check the new outer against all available values.
2124 if (next == class1()) return true;
2125 if (next == outer1()) return true;
2126 outer2 = instanceKlassHandle(THREAD, next);
2127 }
2129 // If by this point we have not found an equality between the
2130 // two classes, we know they are in separate package members.
2131 return false;
2132 }
2135 jint instanceKlass::compute_modifier_flags(TRAPS) const {
2136 klassOop k = as_klassOop();
2137 jint access = access_flags().as_int();
2139 // But check if it happens to be member class.
2140 instanceKlassHandle ik(THREAD, k);
2141 InnerClassesIterator iter(ik);
2142 for (; !iter.done(); iter.next()) {
2143 int ioff = iter.inner_class_info_index();
2144 // Inner class attribute can be zero, skip it.
2145 // Strange but true: JVM spec. allows null inner class refs.
2146 if (ioff == 0) continue;
2148 // only look at classes that are already loaded
2149 // since we are looking for the flags for our self.
2150 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2151 if ((ik->name() == inner_name)) {
2152 // This is really a member class.
2153 access = iter.inner_access_flags();
2154 break;
2155 }
2156 }
2157 // Remember to strip ACC_SUPER bit
2158 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2159 }
2161 jint instanceKlass::jvmti_class_status() const {
2162 jint result = 0;
2164 if (is_linked()) {
2165 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2166 }
2168 if (is_initialized()) {
2169 assert(is_linked(), "Class status is not consistent");
2170 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2171 }
2172 if (is_in_error_state()) {
2173 result |= JVMTI_CLASS_STATUS_ERROR;
2174 }
2175 return result;
2176 }
2178 methodOop instanceKlass::method_at_itable(klassOop holder, int index, TRAPS) {
2179 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2180 int method_table_offset_in_words = ioe->offset()/wordSize;
2181 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2182 / itableOffsetEntry::size();
2184 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2185 // If the interface isn't implemented by the receiver class,
2186 // the VM should throw IncompatibleClassChangeError.
2187 if (cnt >= nof_interfaces) {
2188 THROW_0(vmSymbols::java_lang_IncompatibleClassChangeError());
2189 }
2191 klassOop ik = ioe->interface_klass();
2192 if (ik == holder) break;
2193 }
2195 itableMethodEntry* ime = ioe->first_method_entry(as_klassOop());
2196 methodOop m = ime[index].method();
2197 if (m == NULL) {
2198 THROW_0(vmSymbols::java_lang_AbstractMethodError());
2199 }
2200 return m;
2201 }
2203 // On-stack replacement stuff
2204 void instanceKlass::add_osr_nmethod(nmethod* n) {
2205 // only one compilation can be active
2206 NEEDS_CLEANUP
2207 // This is a short non-blocking critical region, so the no safepoint check is ok.
2208 OsrList_lock->lock_without_safepoint_check();
2209 assert(n->is_osr_method(), "wrong kind of nmethod");
2210 n->set_osr_link(osr_nmethods_head());
2211 set_osr_nmethods_head(n);
2212 // Raise the highest osr level if necessary
2213 if (TieredCompilation) {
2214 methodOop m = n->method();
2215 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2216 }
2217 // Remember to unlock again
2218 OsrList_lock->unlock();
2220 // Get rid of the osr methods for the same bci that have lower levels.
2221 if (TieredCompilation) {
2222 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2223 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2224 if (inv != NULL && inv->is_in_use()) {
2225 inv->make_not_entrant();
2226 }
2227 }
2228 }
2229 }
2232 void instanceKlass::remove_osr_nmethod(nmethod* n) {
2233 // This is a short non-blocking critical region, so the no safepoint check is ok.
2234 OsrList_lock->lock_without_safepoint_check();
2235 assert(n->is_osr_method(), "wrong kind of nmethod");
2236 nmethod* last = NULL;
2237 nmethod* cur = osr_nmethods_head();
2238 int max_level = CompLevel_none; // Find the max comp level excluding n
2239 methodOop m = n->method();
2240 // Search for match
2241 while(cur != NULL && cur != n) {
2242 if (TieredCompilation) {
2243 // Find max level before n
2244 max_level = MAX2(max_level, cur->comp_level());
2245 }
2246 last = cur;
2247 cur = cur->osr_link();
2248 }
2249 nmethod* next = NULL;
2250 if (cur == n) {
2251 next = cur->osr_link();
2252 if (last == NULL) {
2253 // Remove first element
2254 set_osr_nmethods_head(next);
2255 } else {
2256 last->set_osr_link(next);
2257 }
2258 }
2259 n->set_osr_link(NULL);
2260 if (TieredCompilation) {
2261 cur = next;
2262 while (cur != NULL) {
2263 // Find max level after n
2264 max_level = MAX2(max_level, cur->comp_level());
2265 cur = cur->osr_link();
2266 }
2267 m->set_highest_osr_comp_level(max_level);
2268 }
2269 // Remember to unlock again
2270 OsrList_lock->unlock();
2271 }
2273 nmethod* instanceKlass::lookup_osr_nmethod(const methodOop m, int bci, int comp_level, bool match_level) const {
2274 // This is a short non-blocking critical region, so the no safepoint check is ok.
2275 OsrList_lock->lock_without_safepoint_check();
2276 nmethod* osr = osr_nmethods_head();
2277 nmethod* best = NULL;
2278 while (osr != NULL) {
2279 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2280 // There can be a time when a c1 osr method exists but we are waiting
2281 // for a c2 version. When c2 completes its osr nmethod we will trash
2282 // the c1 version and only be able to find the c2 version. However
2283 // while we overflow in the c1 code at back branches we don't want to
2284 // try and switch to the same code as we are already running
2286 if (osr->method() == m &&
2287 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2288 if (match_level) {
2289 if (osr->comp_level() == comp_level) {
2290 // Found a match - return it.
2291 OsrList_lock->unlock();
2292 return osr;
2293 }
2294 } else {
2295 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2296 if (osr->comp_level() == CompLevel_highest_tier) {
2297 // Found the best possible - return it.
2298 OsrList_lock->unlock();
2299 return osr;
2300 }
2301 best = osr;
2302 }
2303 }
2304 }
2305 osr = osr->osr_link();
2306 }
2307 OsrList_lock->unlock();
2308 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2309 return best;
2310 }
2311 return NULL;
2312 }
2314 // -----------------------------------------------------------------------------------------------------
2315 #ifndef PRODUCT
2317 // Printing
2319 #define BULLET " - "
2321 void FieldPrinter::do_field(fieldDescriptor* fd) {
2322 _st->print(BULLET);
2323 if (_obj == NULL) {
2324 fd->print_on(_st);
2325 _st->cr();
2326 } else {
2327 fd->print_on_for(_st, _obj);
2328 _st->cr();
2329 }
2330 }
2333 void instanceKlass::oop_print_on(oop obj, outputStream* st) {
2334 Klass::oop_print_on(obj, st);
2336 if (as_klassOop() == SystemDictionary::String_klass()) {
2337 typeArrayOop value = java_lang_String::value(obj);
2338 juint offset = java_lang_String::offset(obj);
2339 juint length = java_lang_String::length(obj);
2340 if (value != NULL &&
2341 value->is_typeArray() &&
2342 offset <= (juint) value->length() &&
2343 offset + length <= (juint) value->length()) {
2344 st->print(BULLET"string: ");
2345 Handle h_obj(obj);
2346 java_lang_String::print(h_obj, st);
2347 st->cr();
2348 if (!WizardMode) return; // that is enough
2349 }
2350 }
2352 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2353 FieldPrinter print_field(st, obj);
2354 do_nonstatic_fields(&print_field);
2356 if (as_klassOop() == SystemDictionary::Class_klass()) {
2357 st->print(BULLET"signature: ");
2358 java_lang_Class::print_signature(obj, st);
2359 st->cr();
2360 klassOop mirrored_klass = java_lang_Class::as_klassOop(obj);
2361 st->print(BULLET"fake entry for mirror: ");
2362 mirrored_klass->print_value_on(st);
2363 st->cr();
2364 st->print(BULLET"fake entry resolved_constructor: ");
2365 methodOop ctor = java_lang_Class::resolved_constructor(obj);
2366 ctor->print_value_on(st);
2367 klassOop array_klass = java_lang_Class::array_klass(obj);
2368 st->cr();
2369 st->print(BULLET"fake entry for array: ");
2370 array_klass->print_value_on(st);
2371 st->cr();
2372 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2373 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2374 klassOop real_klass = java_lang_Class::as_klassOop(obj);
2375 if (real_klass != NULL && real_klass->klass_part()->oop_is_instance()) {
2376 instanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2377 }
2378 } else if (as_klassOop() == SystemDictionary::MethodType_klass()) {
2379 st->print(BULLET"signature: ");
2380 java_lang_invoke_MethodType::print_signature(obj, st);
2381 st->cr();
2382 }
2383 }
2385 #endif //PRODUCT
2387 void instanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2388 st->print("a ");
2389 name()->print_value_on(st);
2390 obj->print_address_on(st);
2391 if (as_klassOop() == SystemDictionary::String_klass()
2392 && java_lang_String::value(obj) != NULL) {
2393 ResourceMark rm;
2394 int len = java_lang_String::length(obj);
2395 int plen = (len < 24 ? len : 12);
2396 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2397 st->print(" = \"%s\"", str);
2398 if (len > plen)
2399 st->print("...[%d]", len);
2400 } else if (as_klassOop() == SystemDictionary::Class_klass()) {
2401 klassOop k = java_lang_Class::as_klassOop(obj);
2402 st->print(" = ");
2403 if (k != NULL) {
2404 k->print_value_on(st);
2405 } else {
2406 const char* tname = type2name(java_lang_Class::primitive_type(obj));
2407 st->print("%s", tname ? tname : "type?");
2408 }
2409 } else if (as_klassOop() == SystemDictionary::MethodType_klass()) {
2410 st->print(" = ");
2411 java_lang_invoke_MethodType::print_signature(obj, st);
2412 } else if (java_lang_boxing_object::is_instance(obj)) {
2413 st->print(" = ");
2414 java_lang_boxing_object::print(obj, st);
2415 }
2416 }
2418 const char* instanceKlass::internal_name() const {
2419 return external_name();
2420 }
2422 // Verification
2424 class VerifyFieldClosure: public OopClosure {
2425 protected:
2426 template <class T> void do_oop_work(T* p) {
2427 guarantee(Universe::heap()->is_in_closed_subset(p), "should be in heap");
2428 oop obj = oopDesc::load_decode_heap_oop(p);
2429 if (!obj->is_oop_or_null()) {
2430 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
2431 Universe::print();
2432 guarantee(false, "boom");
2433 }
2434 }
2435 public:
2436 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
2437 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2438 };
2440 void instanceKlass::oop_verify_on(oop obj, outputStream* st) {
2441 Klass::oop_verify_on(obj, st);
2442 VerifyFieldClosure blk;
2443 oop_oop_iterate(obj, &blk);
2444 }
2446 // JNIid class for jfieldIDs only
2447 // Note to reviewers:
2448 // These JNI functions are just moved over to column 1 and not changed
2449 // in the compressed oops workspace.
2450 JNIid::JNIid(klassOop holder, int offset, JNIid* next) {
2451 _holder = holder;
2452 _offset = offset;
2453 _next = next;
2454 debug_only(_is_static_field_id = false;)
2455 }
2458 JNIid* JNIid::find(int offset) {
2459 JNIid* current = this;
2460 while (current != NULL) {
2461 if (current->offset() == offset) return current;
2462 current = current->next();
2463 }
2464 return NULL;
2465 }
2467 void JNIid::oops_do(OopClosure* f) {
2468 for (JNIid* cur = this; cur != NULL; cur = cur->next()) {
2469 f->do_oop(cur->holder_addr());
2470 }
2471 }
2473 void JNIid::deallocate(JNIid* current) {
2474 while (current != NULL) {
2475 JNIid* next = current->next();
2476 delete current;
2477 current = next;
2478 }
2479 }
2482 void JNIid::verify(klassOop holder) {
2483 int first_field_offset = instanceMirrorKlass::offset_of_static_fields();
2484 int end_field_offset;
2485 end_field_offset = first_field_offset + (instanceKlass::cast(holder)->static_field_size() * wordSize);
2487 JNIid* current = this;
2488 while (current != NULL) {
2489 guarantee(current->holder() == holder, "Invalid klass in JNIid");
2490 #ifdef ASSERT
2491 int o = current->offset();
2492 if (current->is_static_field_id()) {
2493 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
2494 }
2495 #endif
2496 current = current->next();
2497 }
2498 }
2501 #ifdef ASSERT
2502 void instanceKlass::set_init_state(ClassState state) {
2503 bool good_state = as_klassOop()->is_shared() ? (_init_state <= state)
2504 : (_init_state < state);
2505 assert(good_state || state == allocated, "illegal state transition");
2506 _init_state = (u1)state;
2507 }
2508 #endif
2511 // RedefineClasses() support for previous versions:
2513 // Add an information node that contains weak references to the
2514 // interesting parts of the previous version of the_class.
2515 // This is also where we clean out any unused weak references.
2516 // Note that while we delete nodes from the _previous_versions
2517 // array, we never delete the array itself until the klass is
2518 // unloaded. The has_been_redefined() query depends on that fact.
2519 //
2520 void instanceKlass::add_previous_version(instanceKlassHandle ikh,
2521 BitMap* emcp_methods, int emcp_method_count) {
2522 assert(Thread::current()->is_VM_thread(),
2523 "only VMThread can add previous versions");
2525 if (_previous_versions == NULL) {
2526 // This is the first previous version so make some space.
2527 // Start with 2 elements under the assumption that the class
2528 // won't be redefined much.
2529 _previous_versions = new (ResourceObj::C_HEAP)
2530 GrowableArray<PreviousVersionNode *>(2, true);
2531 }
2533 // RC_TRACE macro has an embedded ResourceMark
2534 RC_TRACE(0x00000100, ("adding previous version ref for %s @%d, EMCP_cnt=%d",
2535 ikh->external_name(), _previous_versions->length(), emcp_method_count));
2536 constantPoolHandle cp_h(ikh->constants());
2537 jobject cp_ref;
2538 if (cp_h->is_shared()) {
2539 // a shared ConstantPool requires a regular reference; a weak
2540 // reference would be collectible
2541 cp_ref = JNIHandles::make_global(cp_h);
2542 } else {
2543 cp_ref = JNIHandles::make_weak_global(cp_h);
2544 }
2545 PreviousVersionNode * pv_node = NULL;
2546 objArrayOop old_methods = ikh->methods();
2548 if (emcp_method_count == 0) {
2549 // non-shared ConstantPool gets a weak reference
2550 pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), NULL);
2551 RC_TRACE(0x00000400,
2552 ("add: all methods are obsolete; flushing any EMCP weak refs"));
2553 } else {
2554 int local_count = 0;
2555 GrowableArray<jweak>* method_refs = new (ResourceObj::C_HEAP)
2556 GrowableArray<jweak>(emcp_method_count, true);
2557 for (int i = 0; i < old_methods->length(); i++) {
2558 if (emcp_methods->at(i)) {
2559 // this old method is EMCP so save a weak ref
2560 methodOop old_method = (methodOop) old_methods->obj_at(i);
2561 methodHandle old_method_h(old_method);
2562 jweak method_ref = JNIHandles::make_weak_global(old_method_h);
2563 method_refs->append(method_ref);
2564 if (++local_count >= emcp_method_count) {
2565 // no more EMCP methods so bail out now
2566 break;
2567 }
2568 }
2569 }
2570 // non-shared ConstantPool gets a weak reference
2571 pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), method_refs);
2572 }
2574 _previous_versions->append(pv_node);
2576 // Using weak references allows the interesting parts of previous
2577 // classes to be GC'ed when they are no longer needed. Since the
2578 // caller is the VMThread and we are at a safepoint, this is a good
2579 // time to clear out unused weak references.
2581 RC_TRACE(0x00000400, ("add: previous version length=%d",
2582 _previous_versions->length()));
2584 // skip the last entry since we just added it
2585 for (int i = _previous_versions->length() - 2; i >= 0; i--) {
2586 // check the previous versions array for a GC'ed weak refs
2587 pv_node = _previous_versions->at(i);
2588 cp_ref = pv_node->prev_constant_pool();
2589 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
2590 if (cp_ref == NULL) {
2591 delete pv_node;
2592 _previous_versions->remove_at(i);
2593 // Since we are traversing the array backwards, we don't have to
2594 // do anything special with the index.
2595 continue; // robustness
2596 }
2598 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2599 if (cp == NULL) {
2600 // this entry has been GC'ed so remove it
2601 delete pv_node;
2602 _previous_versions->remove_at(i);
2603 // Since we are traversing the array backwards, we don't have to
2604 // do anything special with the index.
2605 continue;
2606 } else {
2607 RC_TRACE(0x00000400, ("add: previous version @%d is alive", i));
2608 }
2610 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2611 if (method_refs != NULL) {
2612 RC_TRACE(0x00000400, ("add: previous methods length=%d",
2613 method_refs->length()));
2614 for (int j = method_refs->length() - 1; j >= 0; j--) {
2615 jweak method_ref = method_refs->at(j);
2616 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
2617 if (method_ref == NULL) {
2618 method_refs->remove_at(j);
2619 // Since we are traversing the array backwards, we don't have to
2620 // do anything special with the index.
2621 continue; // robustness
2622 }
2624 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2625 if (method == NULL || emcp_method_count == 0) {
2626 // This method entry has been GC'ed or the current
2627 // RedefineClasses() call has made all methods obsolete
2628 // so remove it.
2629 JNIHandles::destroy_weak_global(method_ref);
2630 method_refs->remove_at(j);
2631 } else {
2632 // RC_TRACE macro has an embedded ResourceMark
2633 RC_TRACE(0x00000400,
2634 ("add: %s(%s): previous method @%d in version @%d is alive",
2635 method->name()->as_C_string(), method->signature()->as_C_string(),
2636 j, i));
2637 }
2638 }
2639 }
2640 }
2642 int obsolete_method_count = old_methods->length() - emcp_method_count;
2644 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
2645 _previous_versions->length() > 1) {
2646 // We have a mix of obsolete and EMCP methods. If there is more
2647 // than the previous version that we just added, then we have to
2648 // clear out any matching EMCP method entries the hard way.
2649 int local_count = 0;
2650 for (int i = 0; i < old_methods->length(); i++) {
2651 if (!emcp_methods->at(i)) {
2652 // only obsolete methods are interesting
2653 methodOop old_method = (methodOop) old_methods->obj_at(i);
2654 Symbol* m_name = old_method->name();
2655 Symbol* m_signature = old_method->signature();
2657 // skip the last entry since we just added it
2658 for (int j = _previous_versions->length() - 2; j >= 0; j--) {
2659 // check the previous versions array for a GC'ed weak refs
2660 pv_node = _previous_versions->at(j);
2661 cp_ref = pv_node->prev_constant_pool();
2662 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
2663 if (cp_ref == NULL) {
2664 delete pv_node;
2665 _previous_versions->remove_at(j);
2666 // Since we are traversing the array backwards, we don't have to
2667 // do anything special with the index.
2668 continue; // robustness
2669 }
2671 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2672 if (cp == NULL) {
2673 // this entry has been GC'ed so remove it
2674 delete pv_node;
2675 _previous_versions->remove_at(j);
2676 // Since we are traversing the array backwards, we don't have to
2677 // do anything special with the index.
2678 continue;
2679 }
2681 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2682 if (method_refs == NULL) {
2683 // We have run into a PreviousVersion generation where
2684 // all methods were made obsolete during that generation's
2685 // RedefineClasses() operation. At the time of that
2686 // operation, all EMCP methods were flushed so we don't
2687 // have to go back any further.
2688 //
2689 // A NULL method_refs is different than an empty method_refs.
2690 // We cannot infer any optimizations about older generations
2691 // from an empty method_refs for the current generation.
2692 break;
2693 }
2695 for (int k = method_refs->length() - 1; k >= 0; k--) {
2696 jweak method_ref = method_refs->at(k);
2697 assert(method_ref != NULL,
2698 "weak method ref was unexpectedly cleared");
2699 if (method_ref == NULL) {
2700 method_refs->remove_at(k);
2701 // Since we are traversing the array backwards, we don't
2702 // have to do anything special with the index.
2703 continue; // robustness
2704 }
2706 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2707 if (method == NULL) {
2708 // this method entry has been GC'ed so skip it
2709 JNIHandles::destroy_weak_global(method_ref);
2710 method_refs->remove_at(k);
2711 continue;
2712 }
2714 if (method->name() == m_name &&
2715 method->signature() == m_signature) {
2716 // The current RedefineClasses() call has made all EMCP
2717 // versions of this method obsolete so mark it as obsolete
2718 // and remove the weak ref.
2719 RC_TRACE(0x00000400,
2720 ("add: %s(%s): flush obsolete method @%d in version @%d",
2721 m_name->as_C_string(), m_signature->as_C_string(), k, j));
2723 method->set_is_obsolete();
2724 JNIHandles::destroy_weak_global(method_ref);
2725 method_refs->remove_at(k);
2726 break;
2727 }
2728 }
2730 // The previous loop may not find a matching EMCP method, but
2731 // that doesn't mean that we can optimize and not go any
2732 // further back in the PreviousVersion generations. The EMCP
2733 // method for this generation could have already been GC'ed,
2734 // but there still may be an older EMCP method that has not
2735 // been GC'ed.
2736 }
2738 if (++local_count >= obsolete_method_count) {
2739 // no more obsolete methods so bail out now
2740 break;
2741 }
2742 }
2743 }
2744 }
2745 } // end add_previous_version()
2748 // Determine if instanceKlass has a previous version.
2749 bool instanceKlass::has_previous_version() const {
2750 if (_previous_versions == NULL) {
2751 // no previous versions array so answer is easy
2752 return false;
2753 }
2755 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2756 // Check the previous versions array for an info node that hasn't
2757 // been GC'ed
2758 PreviousVersionNode * pv_node = _previous_versions->at(i);
2760 jobject cp_ref = pv_node->prev_constant_pool();
2761 assert(cp_ref != NULL, "cp reference was unexpectedly cleared");
2762 if (cp_ref == NULL) {
2763 continue; // robustness
2764 }
2766 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2767 if (cp != NULL) {
2768 // we have at least one previous version
2769 return true;
2770 }
2772 // We don't have to check the method refs. If the constant pool has
2773 // been GC'ed then so have the methods.
2774 }
2776 // all of the underlying nodes' info has been GC'ed
2777 return false;
2778 } // end has_previous_version()
2780 methodOop instanceKlass::method_with_idnum(int idnum) {
2781 methodOop m = NULL;
2782 if (idnum < methods()->length()) {
2783 m = (methodOop) methods()->obj_at(idnum);
2784 }
2785 if (m == NULL || m->method_idnum() != idnum) {
2786 for (int index = 0; index < methods()->length(); ++index) {
2787 m = (methodOop) methods()->obj_at(index);
2788 if (m->method_idnum() == idnum) {
2789 return m;
2790 }
2791 }
2792 }
2793 return m;
2794 }
2797 // Set the annotation at 'idnum' to 'anno'.
2798 // We don't want to create or extend the array if 'anno' is NULL, since that is the
2799 // default value. However, if the array exists and is long enough, we must set NULL values.
2800 void instanceKlass::set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p) {
2801 objArrayOop md = *md_p;
2802 if (md != NULL && md->length() > idnum) {
2803 md->obj_at_put(idnum, anno);
2804 } else if (anno != NULL) {
2805 // create the array
2806 int length = MAX2(idnum+1, (int)_idnum_allocated_count);
2807 md = oopFactory::new_system_objArray(length, Thread::current());
2808 if (*md_p != NULL) {
2809 // copy the existing entries
2810 for (int index = 0; index < (*md_p)->length(); index++) {
2811 md->obj_at_put(index, (*md_p)->obj_at(index));
2812 }
2813 }
2814 set_annotations(md, md_p);
2815 md->obj_at_put(idnum, anno);
2816 } // if no array and idnum isn't included there is nothing to do
2817 }
2819 // Construct a PreviousVersionNode entry for the array hung off
2820 // the instanceKlass.
2821 PreviousVersionNode::PreviousVersionNode(jobject prev_constant_pool,
2822 bool prev_cp_is_weak, GrowableArray<jweak>* prev_EMCP_methods) {
2824 _prev_constant_pool = prev_constant_pool;
2825 _prev_cp_is_weak = prev_cp_is_weak;
2826 _prev_EMCP_methods = prev_EMCP_methods;
2827 }
2830 // Destroy a PreviousVersionNode
2831 PreviousVersionNode::~PreviousVersionNode() {
2832 if (_prev_constant_pool != NULL) {
2833 if (_prev_cp_is_weak) {
2834 JNIHandles::destroy_weak_global(_prev_constant_pool);
2835 } else {
2836 JNIHandles::destroy_global(_prev_constant_pool);
2837 }
2838 }
2840 if (_prev_EMCP_methods != NULL) {
2841 for (int i = _prev_EMCP_methods->length() - 1; i >= 0; i--) {
2842 jweak method_ref = _prev_EMCP_methods->at(i);
2843 if (method_ref != NULL) {
2844 JNIHandles::destroy_weak_global(method_ref);
2845 }
2846 }
2847 delete _prev_EMCP_methods;
2848 }
2849 }
2852 // Construct a PreviousVersionInfo entry
2853 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
2854 _prev_constant_pool_handle = constantPoolHandle(); // NULL handle
2855 _prev_EMCP_method_handles = NULL;
2857 jobject cp_ref = pv_node->prev_constant_pool();
2858 assert(cp_ref != NULL, "constant pool ref was unexpectedly cleared");
2859 if (cp_ref == NULL) {
2860 return; // robustness
2861 }
2863 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2864 if (cp == NULL) {
2865 // Weak reference has been GC'ed. Since the constant pool has been
2866 // GC'ed, the methods have also been GC'ed.
2867 return;
2868 }
2870 // make the constantPoolOop safe to return
2871 _prev_constant_pool_handle = constantPoolHandle(cp);
2873 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2874 if (method_refs == NULL) {
2875 // the instanceKlass did not have any EMCP methods
2876 return;
2877 }
2879 _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
2881 int n_methods = method_refs->length();
2882 for (int i = 0; i < n_methods; i++) {
2883 jweak method_ref = method_refs->at(i);
2884 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
2885 if (method_ref == NULL) {
2886 continue; // robustness
2887 }
2889 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2890 if (method == NULL) {
2891 // this entry has been GC'ed so skip it
2892 continue;
2893 }
2895 // make the methodOop safe to return
2896 _prev_EMCP_method_handles->append(methodHandle(method));
2897 }
2898 }
2901 // Destroy a PreviousVersionInfo
2902 PreviousVersionInfo::~PreviousVersionInfo() {
2903 // Since _prev_EMCP_method_handles is not C-heap allocated, we
2904 // don't have to delete it.
2905 }
2908 // Construct a helper for walking the previous versions array
2909 PreviousVersionWalker::PreviousVersionWalker(instanceKlass *ik) {
2910 _previous_versions = ik->previous_versions();
2911 _current_index = 0;
2912 // _hm needs no initialization
2913 _current_p = NULL;
2914 }
2917 // Destroy a PreviousVersionWalker
2918 PreviousVersionWalker::~PreviousVersionWalker() {
2919 // Delete the current info just in case the caller didn't walk to
2920 // the end of the previous versions list. No harm if _current_p is
2921 // already NULL.
2922 delete _current_p;
2924 // When _hm is destroyed, all the Handles returned in
2925 // PreviousVersionInfo objects will be destroyed.
2926 // Also, after this destructor is finished it will be
2927 // safe to delete the GrowableArray allocated in the
2928 // PreviousVersionInfo objects.
2929 }
2932 // Return the interesting information for the next previous version
2933 // of the klass. Returns NULL if there are no more previous versions.
2934 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
2935 if (_previous_versions == NULL) {
2936 // no previous versions so nothing to return
2937 return NULL;
2938 }
2940 delete _current_p; // cleanup the previous info for the caller
2941 _current_p = NULL; // reset to NULL so we don't delete same object twice
2943 int length = _previous_versions->length();
2945 while (_current_index < length) {
2946 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
2947 PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP)
2948 PreviousVersionInfo(pv_node);
2950 constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
2951 if (cp_h.is_null()) {
2952 delete pv_info;
2954 // The underlying node's info has been GC'ed so try the next one.
2955 // We don't have to check the methods. If the constant pool has
2956 // GC'ed then so have the methods.
2957 continue;
2958 }
2960 // Found a node with non GC'ed info so return it. The caller will
2961 // need to delete pv_info when they are done with it.
2962 _current_p = pv_info;
2963 return pv_info;
2964 }
2966 // all of the underlying nodes' info has been GC'ed
2967 return NULL;
2968 } // end next_previous_version()