1 /*
2 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/verifier.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "gc_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
80
81 #ifdef DTRACE_ENABLED
82
83 #ifndef USDT2
84
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);
101
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 }
114
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 */
128
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 }
149
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 */
163
164 #else // ndef DTRACE_ENABLED
165
166 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
167 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
168
169 #endif // ndef DTRACE_ENABLED
170
171 bool instanceKlass::should_be_initialized() const {
172 return !is_initialized();
173 }
174
175 klassVtable* instanceKlass::vtable() const {
176 return new klassVtable(as_klassOop(), start_of_vtable(), vtable_length() / vtableEntry::size());
177 }
178
179 klassItable* instanceKlass::itable() const {
180 return new klassItable(as_klassOop());
181 }
182
183 void instanceKlass::eager_initialize(Thread *thread) {
184 if (!EagerInitialization) return;
185
186 if (this->is_not_initialized()) {
187 // abort if the the class has a class initializer
188 if (this->class_initializer() != NULL) return;
189
190 // abort if it is java.lang.Object (initialization is handled in genesis)
191 klassOop super = this->super();
192 if (super == NULL) return;
193
194 // abort if the super class should be initialized
195 if (!instanceKlass::cast(super)->is_initialized()) return;
196
197 // call body to expose the this pointer
198 instanceKlassHandle this_oop(thread, this->as_klassOop());
199 eager_initialize_impl(this_oop);
200 }
201 }
202
203
204 void instanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
205 EXCEPTION_MARK;
206 ObjectLocker ol(this_oop, THREAD);
207
208 // abort if someone beat us to the initialization
209 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized()
210
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.
216
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 }
232
233
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 }
249
250
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 }
258
259
260 // Used exclusively by the shared spaces dump mechanism to prevent
261 // classes mapped into the shared regions in new VMs from appearing linked.
262
263 void instanceKlass::unlink_class() {
264 assert(is_linked(), "must be linked");
265 _init_state = loaded;
266 }
267
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 }
275
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 }
286
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 }
299
300 // Timing
301 // timer handles recursion
302 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
303 JavaThread* jt = (JavaThread*)THREAD;
304
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 }
319
320 link_class_impl(super, throw_verifyerror, CHECK_false);
321 }
322
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 }
331
332 // in case the class is linked in the process of linking its superclasses
333 if (this_oop->is_linked()) {
334 return true;
335 }
336
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);
345
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 }
368
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 }
375
376 // also sets rewritten
377 this_oop->rewrite_class(CHECK_false);
378 }
379
380 // relocate jsrs and link methods after they are all rewritten
381 this_oop->relocate_and_link_methods(CHECK_false);
382
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 }
410
411
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 }
425
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 }
434
435
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);
440
441 DTRACE_CLASSINIT_PROBE(required, instanceKlass::cast(this_oop()), -1);
442
443 bool wait = false;
444
445 // refer to the JVM book page 47 for description of steps
446 // Step 1
447 { ObjectLocker ol(this_oop, THREAD);
448
449 Thread *self = THREAD; // it's passed the current thread
450
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 }
459
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 }
465
466 // Step 4
467 if (this_oop->is_initialized()) {
468 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, instanceKlass::cast(this_oop()), -1,wait);
469 return;
470 }
471
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 }
488
489 // Step 6
490 this_oop->set_init_state(being_initialized);
491 this_oop->set_init_thread(self);
492 }
493
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);
498
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 }
511
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 }
527
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 }
556
557
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 }
563
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 }
569
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;
575
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;
585
586 // Update number of implementors
587 int i = _nof_implementors++;
588
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 }
598
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 }
604
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 }
610
611
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 }
622
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 }
629
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 }
648
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 }
656
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 }
667
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 THROW_OOP_0(Universe::out_of_memory_error_array_size());
673 }
674 int size = objArrayOopDesc::object_size(length);
675 klassOop ak = array_klass(n, CHECK_NULL);
676 KlassHandle h_ak (THREAD, ak);
677 objArrayOop o =
678 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
679 return o;
680 }
681
682 instanceOop instanceKlass::register_finalizer(instanceOop i, TRAPS) {
683 if (TraceFinalizerRegistration) {
684 tty->print("Registered ");
685 i->print_value_on(tty);
686 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
687 }
688 instanceHandle h_i(THREAD, i);
689 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
690 JavaValue result(T_VOID);
691 JavaCallArguments args(h_i);
692 methodHandle mh (THREAD, Universe::finalizer_register_method());
693 JavaCalls::call(&result, mh, &args, CHECK_NULL);
694 return h_i();
695 }
696
697 instanceOop instanceKlass::allocate_instance(TRAPS) {
698 assert(!oop_is_instanceMirror(), "wrong allocation path");
699 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
700 int size = size_helper(); // Query before forming handle.
701
702 KlassHandle h_k(THREAD, as_klassOop());
703
704 instanceOop i;
705
706 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
707 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
708 i = register_finalizer(i, CHECK_NULL);
709 }
710 return i;
711 }
712
713 instanceOop instanceKlass::allocate_permanent_instance(TRAPS) {
714 // Finalizer registration occurs in the Object.<init> constructor
715 // and constructors normally aren't run when allocating perm
716 // instances so simply disallow finalizable perm objects. This can
717 // be relaxed if a need for it is found.
718 assert(!has_finalizer(), "perm objects not allowed to have finalizers");
719 assert(!oop_is_instanceMirror(), "wrong allocation path");
720 int size = size_helper(); // Query before forming handle.
721 KlassHandle h_k(THREAD, as_klassOop());
722 instanceOop i = (instanceOop)
723 CollectedHeap::permanent_obj_allocate(h_k, size, CHECK_NULL);
724 return i;
725 }
726
727 void instanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
728 if (is_interface() || is_abstract()) {
729 ResourceMark rm(THREAD);
730 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
731 : vmSymbols::java_lang_InstantiationException(), external_name());
732 }
733 if (as_klassOop() == SystemDictionary::Class_klass()) {
734 ResourceMark rm(THREAD);
735 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
736 : vmSymbols::java_lang_IllegalAccessException(), external_name());
737 }
738 }
739
740 klassOop instanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
741 instanceKlassHandle this_oop(THREAD, as_klassOop());
742 return array_klass_impl(this_oop, or_null, n, THREAD);
743 }
744
745 klassOop instanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
746 if (this_oop->array_klasses() == NULL) {
747 if (or_null) return NULL;
748
749 ResourceMark rm;
750 JavaThread *jt = (JavaThread *)THREAD;
751 {
752 // Atomic creation of array_klasses
753 MutexLocker mc(Compile_lock, THREAD); // for vtables
754 MutexLocker ma(MultiArray_lock, THREAD);
755
756 // Check if update has already taken place
757 if (this_oop->array_klasses() == NULL) {
758 objArrayKlassKlass* oakk =
759 (objArrayKlassKlass*)Universe::objArrayKlassKlassObj()->klass_part();
760
761 klassOop k = oakk->allocate_objArray_klass(1, this_oop, CHECK_NULL);
762 this_oop->set_array_klasses(k);
763 }
764 }
765 }
766 // _this will always be set at this point
767 objArrayKlass* oak = (objArrayKlass*)this_oop->array_klasses()->klass_part();
768 if (or_null) {
769 return oak->array_klass_or_null(n);
770 }
771 return oak->array_klass(n, CHECK_NULL);
772 }
773
774 klassOop instanceKlass::array_klass_impl(bool or_null, TRAPS) {
775 return array_klass_impl(or_null, 1, THREAD);
776 }
777
778 void instanceKlass::call_class_initializer(TRAPS) {
779 instanceKlassHandle ik (THREAD, as_klassOop());
780 call_class_initializer_impl(ik, THREAD);
781 }
782
783 static int call_class_initializer_impl_counter = 0; // for debugging
784
785 methodOop instanceKlass::class_initializer() {
786 methodOop clinit = find_method(
787 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
788 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
789 return clinit;
790 }
791 return NULL;
792 }
793
794 void instanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
795 methodHandle h_method(THREAD, this_oop->class_initializer());
796 assert(!this_oop->is_initialized(), "we cannot initialize twice");
797 if (TraceClassInitialization) {
798 tty->print("%d Initializing ", call_class_initializer_impl_counter++);
799 this_oop->name()->print_value();
800 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
801 }
802 if (h_method() != NULL) {
803 JavaCallArguments args; // No arguments
804 JavaValue result(T_VOID);
805 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
806 }
807 }
808
809
810 void instanceKlass::mask_for(methodHandle method, int bci,
811 InterpreterOopMap* entry_for) {
812 // Dirty read, then double-check under a lock.
813 if (_oop_map_cache == NULL) {
814 // Otherwise, allocate a new one.
815 MutexLocker x(OopMapCacheAlloc_lock);
816 // First time use. Allocate a cache in C heap
817 if (_oop_map_cache == NULL) {
818 _oop_map_cache = new OopMapCache();
819 }
820 }
821 // _oop_map_cache is constant after init; lookup below does is own locking.
822 _oop_map_cache->lookup(method, bci, entry_for);
823 }
824
825
826 bool instanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
827 for (JavaFieldStream fs(as_klassOop()); !fs.done(); fs.next()) {
828 Symbol* f_name = fs.name();
829 Symbol* f_sig = fs.signature();
830 if (f_name == name && f_sig == sig) {
831 fd->initialize(as_klassOop(), fs.index());
832 return true;
833 }
834 }
835 return false;
836 }
837
838
839 void instanceKlass::shared_symbols_iterate(SymbolClosure* closure) {
840 Klass::shared_symbols_iterate(closure);
841 closure->do_symbol(&_generic_signature);
842 closure->do_symbol(&_source_file_name);
843 closure->do_symbol(&_source_debug_extension);
844
845 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
846 int name_index = fs.name_index();
847 closure->do_symbol(constants()->symbol_at_addr(name_index));
848 int sig_index = fs.signature_index();
849 closure->do_symbol(constants()->symbol_at_addr(sig_index));
850 }
851 }
852
853
854 klassOop instanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
855 const int n = local_interfaces()->length();
856 for (int i = 0; i < n; i++) {
857 klassOop intf1 = klassOop(local_interfaces()->obj_at(i));
858 assert(Klass::cast(intf1)->is_interface(), "just checking type");
859 // search for field in current interface
860 if (instanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
861 assert(fd->is_static(), "interface field must be static");
862 return intf1;
863 }
864 // search for field in direct superinterfaces
865 klassOop intf2 = instanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
866 if (intf2 != NULL) return intf2;
867 }
868 // otherwise field lookup fails
869 return NULL;
870 }
871
872
873 klassOop instanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
874 // search order according to newest JVM spec (5.4.3.2, p.167).
875 // 1) search for field in current klass
876 if (find_local_field(name, sig, fd)) {
877 return as_klassOop();
878 }
879 // 2) search for field recursively in direct superinterfaces
880 { klassOop intf = find_interface_field(name, sig, fd);
881 if (intf != NULL) return intf;
882 }
883 // 3) apply field lookup recursively if superclass exists
884 { klassOop supr = super();
885 if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, fd);
886 }
887 // 4) otherwise field lookup fails
888 return NULL;
889 }
890
891
892 klassOop instanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
893 // search order according to newest JVM spec (5.4.3.2, p.167).
894 // 1) search for field in current klass
895 if (find_local_field(name, sig, fd)) {
896 if (fd->is_static() == is_static) return as_klassOop();
897 }
898 // 2) search for field recursively in direct superinterfaces
899 if (is_static) {
900 klassOop intf = find_interface_field(name, sig, fd);
901 if (intf != NULL) return intf;
902 }
903 // 3) apply field lookup recursively if superclass exists
904 { klassOop supr = super();
905 if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
906 }
907 // 4) otherwise field lookup fails
908 return NULL;
909 }
910
911
912 bool instanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
913 for (JavaFieldStream fs(as_klassOop()); !fs.done(); fs.next()) {
914 if (fs.offset() == offset) {
915 fd->initialize(as_klassOop(), fs.index());
916 if (fd->is_static() == is_static) return true;
917 }
918 }
919 return false;
920 }
921
922
923 bool instanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
924 klassOop klass = as_klassOop();
925 while (klass != NULL) {
926 if (instanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
927 return true;
928 }
929 klass = Klass::cast(klass)->super();
930 }
931 return false;
932 }
933
934
935 void instanceKlass::methods_do(void f(methodOop method)) {
936 int len = methods()->length();
937 for (int index = 0; index < len; index++) {
938 methodOop m = methodOop(methods()->obj_at(index));
939 assert(m->is_method(), "must be method");
940 f(m);
941 }
942 }
943
944
945 void instanceKlass::do_local_static_fields(FieldClosure* cl) {
946 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
947 if (fs.access_flags().is_static()) {
948 fieldDescriptor fd;
949 fd.initialize(as_klassOop(), fs.index());
950 cl->do_field(&fd);
951 }
952 }
953 }
954
955
956 void instanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
957 instanceKlassHandle h_this(THREAD, as_klassOop());
958 do_local_static_fields_impl(h_this, f, CHECK);
959 }
960
961
962 void instanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
963 for (JavaFieldStream fs(this_oop()); !fs.done(); fs.next()) {
964 if (fs.access_flags().is_static()) {
965 fieldDescriptor fd;
966 fd.initialize(this_oop(), fs.index());
967 f(&fd, CHECK);
968 }
969 }
970 }
971
972
973 static int compare_fields_by_offset(int* a, int* b) {
974 return a[0] - b[0];
975 }
976
977 void instanceKlass::do_nonstatic_fields(FieldClosure* cl) {
978 instanceKlass* super = superklass();
979 if (super != NULL) {
980 super->do_nonstatic_fields(cl);
981 }
982 fieldDescriptor fd;
983 int length = java_fields_count();
984 // In DebugInfo nonstatic fields are sorted by offset.
985 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1));
986 int j = 0;
987 for (int i = 0; i < length; i += 1) {
988 fd.initialize(as_klassOop(), i);
989 if (!fd.is_static()) {
990 fields_sorted[j + 0] = fd.offset();
991 fields_sorted[j + 1] = i;
992 j += 2;
993 }
994 }
995 if (j > 0) {
996 length = j;
997 // _sort_Fn is defined in growableArray.hpp.
998 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
999 for (int i = 0; i < length; i += 2) {
1000 fd.initialize(as_klassOop(), fields_sorted[i + 1]);
1001 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1002 cl->do_field(&fd);
1003 }
1004 }
1005 FREE_C_HEAP_ARRAY(int, fields_sorted);
1006 }
1007
1008
1009 void instanceKlass::array_klasses_do(void f(klassOop k)) {
1010 if (array_klasses() != NULL)
1011 arrayKlass::cast(array_klasses())->array_klasses_do(f);
1012 }
1013
1014
1015 void instanceKlass::with_array_klasses_do(void f(klassOop k)) {
1016 f(as_klassOop());
1017 array_klasses_do(f);
1018 }
1019
1020 #ifdef ASSERT
1021 static int linear_search(objArrayOop methods, Symbol* name, Symbol* signature) {
1022 int len = methods->length();
1023 for (int index = 0; index < len; index++) {
1024 methodOop m = (methodOop)(methods->obj_at(index));
1025 assert(m->is_method(), "must be method");
1026 if (m->signature() == signature && m->name() == name) {
1027 return index;
1028 }
1029 }
1030 return -1;
1031 }
1032 #endif
1033
1034 methodOop instanceKlass::find_method(Symbol* name, Symbol* signature) const {
1035 return instanceKlass::find_method(methods(), name, signature);
1036 }
1037
1038 methodOop instanceKlass::find_method(objArrayOop methods, Symbol* name, Symbol* signature) {
1039 int len = methods->length();
1040 // methods are sorted, so do binary search
1041 int l = 0;
1042 int h = len - 1;
1043 while (l <= h) {
1044 int mid = (l + h) >> 1;
1045 methodOop m = (methodOop)methods->obj_at(mid);
1046 assert(m->is_method(), "must be method");
1047 int res = m->name()->fast_compare(name);
1048 if (res == 0) {
1049 // found matching name; do linear search to find matching signature
1050 // first, quick check for common case
1051 if (m->signature() == signature) return m;
1052 // search downwards through overloaded methods
1053 int i;
1054 for (i = mid - 1; i >= l; i--) {
1055 methodOop m = (methodOop)methods->obj_at(i);
1056 assert(m->is_method(), "must be method");
1057 if (m->name() != name) break;
1058 if (m->signature() == signature) return m;
1059 }
1060 // search upwards
1061 for (i = mid + 1; i <= h; i++) {
1062 methodOop m = (methodOop)methods->obj_at(i);
1063 assert(m->is_method(), "must be method");
1064 if (m->name() != name) break;
1065 if (m->signature() == signature) return m;
1066 }
1067 // not found
1068 #ifdef ASSERT
1069 int index = linear_search(methods, name, signature);
1070 assert(index == -1, err_msg("binary search should have found entry %d", index));
1071 #endif
1072 return NULL;
1073 } else if (res < 0) {
1074 l = mid + 1;
1075 } else {
1076 h = mid - 1;
1077 }
1078 }
1079 #ifdef ASSERT
1080 int index = linear_search(methods, name, signature);
1081 assert(index == -1, err_msg("binary search should have found entry %d", index));
1082 #endif
1083 return NULL;
1084 }
1085
1086 methodOop instanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
1087 klassOop klass = as_klassOop();
1088 while (klass != NULL) {
1089 methodOop method = instanceKlass::cast(klass)->find_method(name, signature);
1090 if (method != NULL) return method;
1091 klass = instanceKlass::cast(klass)->super();
1092 }
1093 return NULL;
1094 }
1095
1096 // lookup a method in all the interfaces that this class implements
1097 methodOop instanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1098 Symbol* signature) const {
1099 objArrayOop all_ifs = instanceKlass::cast(as_klassOop())->transitive_interfaces();
1100 int num_ifs = all_ifs->length();
1101 instanceKlass *ik = NULL;
1102 for (int i = 0; i < num_ifs; i++) {
1103 ik = instanceKlass::cast(klassOop(all_ifs->obj_at(i)));
1104 methodOop m = ik->lookup_method(name, signature);
1105 if (m != NULL) {
1106 return m;
1107 }
1108 }
1109 return NULL;
1110 }
1111
1112 /* jni_id_for_impl for jfieldIds only */
1113 JNIid* instanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
1114 MutexLocker ml(JfieldIdCreation_lock);
1115 // Retry lookup after we got the lock
1116 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
1117 if (probe == NULL) {
1118 // Slow case, allocate new static field identifier
1119 probe = new JNIid(this_oop->as_klassOop(), offset, this_oop->jni_ids());
1120 this_oop->set_jni_ids(probe);
1121 }
1122 return probe;
1123 }
1124
1125
1126 /* jni_id_for for jfieldIds only */
1127 JNIid* instanceKlass::jni_id_for(int offset) {
1128 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1129 if (probe == NULL) {
1130 probe = jni_id_for_impl(this->as_klassOop(), offset);
1131 }
1132 return probe;
1133 }
1134
1135
1136 // Lookup or create a jmethodID.
1137 // This code is called by the VMThread and JavaThreads so the
1138 // locking has to be done very carefully to avoid deadlocks
1139 // and/or other cache consistency problems.
1140 //
1141 jmethodID instanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
1142 size_t idnum = (size_t)method_h->method_idnum();
1143 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1144 size_t length = 0;
1145 jmethodID id = NULL;
1146
1147 // We use a double-check locking idiom here because this cache is
1148 // performance sensitive. In the normal system, this cache only
1149 // transitions from NULL to non-NULL which is safe because we use
1150 // release_set_methods_jmethod_ids() to advertise the new cache.
1151 // A partially constructed cache should never be seen by a racing
1152 // thread. We also use release_store_ptr() to save a new jmethodID
1153 // in the cache so a partially constructed jmethodID should never be
1154 // seen either. Cache reads of existing jmethodIDs proceed without a
1155 // lock, but cache writes of a new jmethodID requires uniqueness and
1156 // creation of the cache itself requires no leaks so a lock is
1157 // generally acquired in those two cases.
1158 //
1159 // If the RedefineClasses() API has been used, then this cache can
1160 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1161 // Cache creation requires no leaks and we require safety between all
1162 // cache accesses and freeing of the old cache so a lock is generally
1163 // acquired when the RedefineClasses() API has been used.
1164
1165 if (jmeths != NULL) {
1166 // the cache already exists
1167 if (!ik_h->idnum_can_increment()) {
1168 // the cache can't grow so we can just get the current values
1169 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1170 } else {
1171 // cache can grow so we have to be more careful
1172 if (Threads::number_of_threads() == 0 ||
1173 SafepointSynchronize::is_at_safepoint()) {
1174 // we're single threaded or at a safepoint - no locking needed
1175 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1176 } else {
1177 MutexLocker ml(JmethodIdCreation_lock);
1178 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1179 }
1180 }
1181 }
1182 // implied else:
1183 // we need to allocate a cache so default length and id values are good
1184
1185 if (jmeths == NULL || // no cache yet
1186 length <= idnum || // cache is too short
1187 id == NULL) { // cache doesn't contain entry
1188
1189 // This function can be called by the VMThread so we have to do all
1190 // things that might block on a safepoint before grabbing the lock.
1191 // Otherwise, we can deadlock with the VMThread or have a cache
1192 // consistency issue. These vars keep track of what we might have
1193 // to free after the lock is dropped.
1194 jmethodID to_dealloc_id = NULL;
1195 jmethodID* to_dealloc_jmeths = NULL;
1196
1197 // may not allocate new_jmeths or use it if we allocate it
1198 jmethodID* new_jmeths = NULL;
1199 if (length <= idnum) {
1200 // allocate a new cache that might be used
1201 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1202 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1);
1203 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1204 // cache size is stored in element[0], other elements offset by one
1205 new_jmeths[0] = (jmethodID)size;
1206 }
1207
1208 // allocate a new jmethodID that might be used
1209 jmethodID new_id = NULL;
1210 if (method_h->is_old() && !method_h->is_obsolete()) {
1211 // The method passed in is old (but not obsolete), we need to use the current version
1212 methodOop current_method = ik_h->method_with_idnum((int)idnum);
1213 assert(current_method != NULL, "old and but not obsolete, so should exist");
1214 methodHandle current_method_h(current_method == NULL? method_h() : current_method);
1215 new_id = JNIHandles::make_jmethod_id(current_method_h);
1216 } else {
1217 // It is the current version of the method or an obsolete method,
1218 // use the version passed in
1219 new_id = JNIHandles::make_jmethod_id(method_h);
1220 }
1221
1222 if (Threads::number_of_threads() == 0 ||
1223 SafepointSynchronize::is_at_safepoint()) {
1224 // we're single threaded or at a safepoint - no locking needed
1225 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1226 &to_dealloc_id, &to_dealloc_jmeths);
1227 } else {
1228 MutexLocker ml(JmethodIdCreation_lock);
1229 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1230 &to_dealloc_id, &to_dealloc_jmeths);
1231 }
1232
1233 // The lock has been dropped so we can free resources.
1234 // Free up either the old cache or the new cache if we allocated one.
1235 if (to_dealloc_jmeths != NULL) {
1236 FreeHeap(to_dealloc_jmeths);
1237 }
1238 // free up the new ID since it wasn't needed
1239 if (to_dealloc_id != NULL) {
1240 JNIHandles::destroy_jmethod_id(to_dealloc_id);
1241 }
1242 }
1243 return id;
1244 }
1245
1246
1247 // Common code to fetch the jmethodID from the cache or update the
1248 // cache with the new jmethodID. This function should never do anything
1249 // that causes the caller to go to a safepoint or we can deadlock with
1250 // the VMThread or have cache consistency issues.
1251 //
1252 jmethodID instanceKlass::get_jmethod_id_fetch_or_update(
1253 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1254 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1255 jmethodID** to_dealloc_jmeths_p) {
1256 assert(new_id != NULL, "sanity check");
1257 assert(to_dealloc_id_p != NULL, "sanity check");
1258 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1259 assert(Threads::number_of_threads() == 0 ||
1260 SafepointSynchronize::is_at_safepoint() ||
1261 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1262
1263 // reacquire the cache - we are locked, single threaded or at a safepoint
1264 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1265 jmethodID id = NULL;
1266 size_t length = 0;
1267
1268 if (jmeths == NULL || // no cache yet
1269 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1270 if (jmeths != NULL) {
1271 // copy any existing entries from the old cache
1272 for (size_t index = 0; index < length; index++) {
1273 new_jmeths[index+1] = jmeths[index+1];
1274 }
1275 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1276 }
1277 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1278 } else {
1279 // fetch jmethodID (if any) from the existing cache
1280 id = jmeths[idnum+1];
1281 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1282 }
1283 if (id == NULL) {
1284 // No matching jmethodID in the existing cache or we have a new
1285 // cache or we just grew the cache. This cache write is done here
1286 // by the first thread to win the foot race because a jmethodID
1287 // needs to be unique once it is generally available.
1288 id = new_id;
1289
1290 // The jmethodID cache can be read while unlocked so we have to
1291 // make sure the new jmethodID is complete before installing it
1292 // in the cache.
1293 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1294 } else {
1295 *to_dealloc_id_p = new_id; // save new id for later delete
1296 }
1297 return id;
1298 }
1299
1300
1301 // Common code to get the jmethodID cache length and the jmethodID
1302 // value at index idnum if there is one.
1303 //
1304 void instanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1305 size_t idnum, size_t *length_p, jmethodID* id_p) {
1306 assert(cache != NULL, "sanity check");
1307 assert(length_p != NULL, "sanity check");
1308 assert(id_p != NULL, "sanity check");
1309
1310 // cache size is stored in element[0], other elements offset by one
1311 *length_p = (size_t)cache[0];
1312 if (*length_p <= idnum) { // cache is too short
1313 *id_p = NULL;
1314 } else {
1315 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1316 }
1317 }
1318
1319
1320 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1321 jmethodID instanceKlass::jmethod_id_or_null(methodOop method) {
1322 size_t idnum = (size_t)method->method_idnum();
1323 jmethodID* jmeths = methods_jmethod_ids_acquire();
1324 size_t length; // length assigned as debugging crumb
1325 jmethodID id = NULL;
1326 if (jmeths != NULL && // If there is a cache
1327 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1328 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1329 }
1330 return id;
1331 }
1332
1333
1334 // Cache an itable index
1335 void instanceKlass::set_cached_itable_index(size_t idnum, int index) {
1336 int* indices = methods_cached_itable_indices_acquire();
1337 int* to_dealloc_indices = NULL;
1338
1339 // We use a double-check locking idiom here because this cache is
1340 // performance sensitive. In the normal system, this cache only
1341 // transitions from NULL to non-NULL which is safe because we use
1342 // release_set_methods_cached_itable_indices() to advertise the
1343 // new cache. A partially constructed cache should never be seen
1344 // by a racing thread. Cache reads and writes proceed without a
1345 // lock, but creation of the cache itself requires no leaks so a
1346 // lock is generally acquired in that case.
1347 //
1348 // If the RedefineClasses() API has been used, then this cache can
1349 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1350 // Cache creation requires no leaks and we require safety between all
1351 // cache accesses and freeing of the old cache so a lock is generally
1352 // acquired when the RedefineClasses() API has been used.
1353
1354 if (indices == NULL || idnum_can_increment()) {
1355 // we need a cache or the cache can grow
1356 MutexLocker ml(JNICachedItableIndex_lock);
1357 // reacquire the cache to see if another thread already did the work
1358 indices = methods_cached_itable_indices_acquire();
1359 size_t length = 0;
1360 // cache size is stored in element[0], other elements offset by one
1361 if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
1362 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1363 int* new_indices = NEW_C_HEAP_ARRAY(int, size+1);
1364 new_indices[0] = (int)size;
1365 // copy any existing entries
1366 size_t i;
1367 for (i = 0; i < length; i++) {
1368 new_indices[i+1] = indices[i+1];
1369 }
1370 // Set all the rest to -1
1371 for (i = length; i < size; i++) {
1372 new_indices[i+1] = -1;
1373 }
1374 if (indices != NULL) {
1375 // We have an old cache to delete so save it for after we
1376 // drop the lock.
1377 to_dealloc_indices = indices;
1378 }
1379 release_set_methods_cached_itable_indices(indices = new_indices);
1380 }
1381
1382 if (idnum_can_increment()) {
1383 // this cache can grow so we have to write to it safely
1384 indices[idnum+1] = index;
1385 }
1386 } else {
1387 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
1388 }
1389
1390 if (!idnum_can_increment()) {
1391 // The cache cannot grow and this JNI itable index value does not
1392 // have to be unique like a jmethodID. If there is a race to set it,
1393 // it doesn't matter.
1394 indices[idnum+1] = index;
1395 }
1396
1397 if (to_dealloc_indices != NULL) {
1398 // we allocated a new cache so free the old one
1399 FreeHeap(to_dealloc_indices);
1400 }
1401 }
1402
1403
1404 // Retrieve a cached itable index
1405 int instanceKlass::cached_itable_index(size_t idnum) {
1406 int* indices = methods_cached_itable_indices_acquire();
1407 if (indices != NULL && ((size_t)indices[0]) > idnum) {
1408 // indices exist and are long enough, retrieve possible cached
1409 return indices[idnum+1];
1410 }
1411 return -1;
1412 }
1413
1414
1415 //
1416 // Walk the list of dependent nmethods searching for nmethods which
1417 // are dependent on the changes that were passed in and mark them for
1418 // deoptimization. Returns the number of nmethods found.
1419 //
1420 int instanceKlass::mark_dependent_nmethods(DepChange& changes) {
1421 assert_locked_or_safepoint(CodeCache_lock);
1422 int found = 0;
1423 nmethodBucket* b = _dependencies;
1424 while (b != NULL) {
1425 nmethod* nm = b->get_nmethod();
1426 // since dependencies aren't removed until an nmethod becomes a zombie,
1427 // the dependency list may contain nmethods which aren't alive.
1428 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1429 if (TraceDependencies) {
1430 ResourceMark rm;
1431 tty->print_cr("Marked for deoptimization");
1432 tty->print_cr(" context = %s", this->external_name());
1433 changes.print();
1434 nm->print();
1435 nm->print_dependencies();
1436 }
1437 nm->mark_for_deoptimization();
1438 found++;
1439 }
1440 b = b->next();
1441 }
1442 return found;
1443 }
1444
1445
1446 //
1447 // Add an nmethodBucket to the list of dependencies for this nmethod.
1448 // It's possible that an nmethod has multiple dependencies on this klass
1449 // so a count is kept for each bucket to guarantee that creation and
1450 // deletion of dependencies is consistent.
1451 //
1452 void instanceKlass::add_dependent_nmethod(nmethod* nm) {
1453 assert_locked_or_safepoint(CodeCache_lock);
1454 nmethodBucket* b = _dependencies;
1455 nmethodBucket* last = NULL;
1456 while (b != NULL) {
1457 if (nm == b->get_nmethod()) {
1458 b->increment();
1459 return;
1460 }
1461 b = b->next();
1462 }
1463 _dependencies = new nmethodBucket(nm, _dependencies);
1464 }
1465
1466
1467 //
1468 // Decrement count of the nmethod in the dependency list and remove
1469 // the bucket competely when the count goes to 0. This method must
1470 // find a corresponding bucket otherwise there's a bug in the
1471 // recording of dependecies.
1472 //
1473 void instanceKlass::remove_dependent_nmethod(nmethod* nm) {
1474 assert_locked_or_safepoint(CodeCache_lock);
1475 nmethodBucket* b = _dependencies;
1476 nmethodBucket* last = NULL;
1477 while (b != NULL) {
1478 if (nm == b->get_nmethod()) {
1479 if (b->decrement() == 0) {
1480 if (last == NULL) {
1481 _dependencies = b->next();
1482 } else {
1483 last->set_next(b->next());
1484 }
1485 delete b;
1486 }
1487 return;
1488 }
1489 last = b;
1490 b = b->next();
1491 }
1492 #ifdef ASSERT
1493 tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
1494 nm->print();
1495 #endif // ASSERT
1496 ShouldNotReachHere();
1497 }
1498
1499
1500 #ifndef PRODUCT
1501 void instanceKlass::print_dependent_nmethods(bool verbose) {
1502 nmethodBucket* b = _dependencies;
1503 int idx = 0;
1504 while (b != NULL) {
1505 nmethod* nm = b->get_nmethod();
1506 tty->print("[%d] count=%d { ", idx++, b->count());
1507 if (!verbose) {
1508 nm->print_on(tty, "nmethod");
1509 tty->print_cr(" } ");
1510 } else {
1511 nm->print();
1512 nm->print_dependencies();
1513 tty->print_cr("--- } ");
1514 }
1515 b = b->next();
1516 }
1517 }
1518
1519
1520 bool instanceKlass::is_dependent_nmethod(nmethod* nm) {
1521 nmethodBucket* b = _dependencies;
1522 while (b != NULL) {
1523 if (nm == b->get_nmethod()) {
1524 return true;
1525 }
1526 b = b->next();
1527 }
1528 return false;
1529 }
1530 #endif //PRODUCT
1531
1532
1533 #ifdef ASSERT
1534 template <class T> void assert_is_in(T *p) {
1535 T heap_oop = oopDesc::load_heap_oop(p);
1536 if (!oopDesc::is_null(heap_oop)) {
1537 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1538 assert(Universe::heap()->is_in(o), "should be in heap");
1539 }
1540 }
1541 template <class T> void assert_is_in_closed_subset(T *p) {
1542 T heap_oop = oopDesc::load_heap_oop(p);
1543 if (!oopDesc::is_null(heap_oop)) {
1544 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1545 assert(Universe::heap()->is_in_closed_subset(o), "should be in closed");
1546 }
1547 }
1548 template <class T> void assert_is_in_reserved(T *p) {
1549 T heap_oop = oopDesc::load_heap_oop(p);
1550 if (!oopDesc::is_null(heap_oop)) {
1551 oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
1552 assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
1553 }
1554 }
1555 template <class T> void assert_nothing(T *p) {}
1556
1557 #else
1558 template <class T> void assert_is_in(T *p) {}
1559 template <class T> void assert_is_in_closed_subset(T *p) {}
1560 template <class T> void assert_is_in_reserved(T *p) {}
1561 template <class T> void assert_nothing(T *p) {}
1562 #endif // ASSERT
1563
1564 //
1565 // Macros that iterate over areas of oops which are specialized on type of
1566 // oop pointer either narrow or wide, depending on UseCompressedOops
1567 //
1568 // Parameters are:
1569 // T - type of oop to point to (either oop or narrowOop)
1570 // start_p - starting pointer for region to iterate over
1571 // count - number of oops or narrowOops to iterate over
1572 // do_oop - action to perform on each oop (it's arbitrary C code which
1573 // makes it more efficient to put in a macro rather than making
1574 // it a template function)
1575 // assert_fn - assert function which is template function because performance
1576 // doesn't matter when enabled.
1577 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
1578 T, start_p, count, do_oop, \
1579 assert_fn) \
1580 { \
1581 T* p = (T*)(start_p); \
1582 T* const end = p + (count); \
1583 while (p < end) { \
1584 (assert_fn)(p); \
1585 do_oop; \
1586 ++p; \
1587 } \
1588 }
1589
1590 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
1591 T, start_p, count, do_oop, \
1592 assert_fn) \
1593 { \
1594 T* const start = (T*)(start_p); \
1595 T* p = start + (count); \
1596 while (start < p) { \
1597 --p; \
1598 (assert_fn)(p); \
1599 do_oop; \
1600 } \
1601 }
1602
1603 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
1604 T, start_p, count, low, high, \
1605 do_oop, assert_fn) \
1606 { \
1607 T* const l = (T*)(low); \
1608 T* const h = (T*)(high); \
1609 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
1610 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \
1611 "bounded region must be properly aligned"); \
1612 T* p = (T*)(start_p); \
1613 T* end = p + (count); \
1614 if (p < l) p = l; \
1615 if (end > h) end = h; \
1616 while (p < end) { \
1617 (assert_fn)(p); \
1618 do_oop; \
1619 ++p; \
1620 } \
1621 }
1622
1623
1624 // The following macros call specialized macros, passing either oop or
1625 // narrowOop as the specialization type. These test the UseCompressedOops
1626 // flag.
1627 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \
1628 { \
1629 /* Compute oopmap block range. The common case \
1630 is nonstatic_oop_map_size == 1. */ \
1631 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1632 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
1633 if (UseCompressedOops) { \
1634 while (map < end_map) { \
1635 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
1636 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1637 do_oop, assert_fn) \
1638 ++map; \
1639 } \
1640 } else { \
1641 while (map < end_map) { \
1642 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \
1643 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1644 do_oop, assert_fn) \
1645 ++map; \
1646 } \
1647 } \
1648 }
1649
1650 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \
1651 { \
1652 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \
1653 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \
1654 if (UseCompressedOops) { \
1655 while (start_map < map) { \
1656 --map; \
1657 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \
1658 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1659 do_oop, assert_fn) \
1660 } \
1661 } else { \
1662 while (start_map < map) { \
1663 --map; \
1664 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \
1665 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1666 do_oop, assert_fn) \
1667 } \
1668 } \
1669 }
1670
1671 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \
1672 assert_fn) \
1673 { \
1674 /* Compute oopmap block range. The common case is \
1675 nonstatic_oop_map_size == 1, so we accept the \
1676 usually non-existent extra overhead of examining \
1677 all the maps. */ \
1678 OopMapBlock* map = start_of_nonstatic_oop_maps(); \
1679 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \
1680 if (UseCompressedOops) { \
1681 while (map < end_map) { \
1682 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
1683 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \
1684 low, high, \
1685 do_oop, assert_fn) \
1686 ++map; \
1687 } \
1688 } else { \
1689 while (map < end_map) { \
1690 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \
1691 obj->obj_field_addr<oop>(map->offset()), map->count(), \
1692 low, high, \
1693 do_oop, assert_fn) \
1694 ++map; \
1695 } \
1696 } \
1697 }
1698
1699 void instanceKlass::oop_follow_contents(oop obj) {
1700 assert(obj != NULL, "can't follow the content of NULL object");
1701 obj->follow_header();
1702 InstanceKlass_OOP_MAP_ITERATE( \
1703 obj, \
1704 MarkSweep::mark_and_push(p), \
1705 assert_is_in_closed_subset)
1706 }
1707
1708 #ifndef SERIALGC
1709 void instanceKlass::oop_follow_contents(ParCompactionManager* cm,
1710 oop obj) {
1711 assert(obj != NULL, "can't follow the content of NULL object");
1712 obj->follow_header(cm);
1713 InstanceKlass_OOP_MAP_ITERATE( \
1714 obj, \
1715 PSParallelCompact::mark_and_push(cm, p), \
1716 assert_is_in)
1717 }
1718 #endif // SERIALGC
1719
1720 // closure's do_header() method dicates whether the given closure should be
1721 // applied to the klass ptr in the object header.
1722
1723 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
1724 \
1725 int instanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
1726 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
1727 /* header */ \
1728 if (closure->do_header()) { \
1729 obj->oop_iterate_header(closure); \
1730 } \
1731 InstanceKlass_OOP_MAP_ITERATE( \
1732 obj, \
1733 SpecializationStats:: \
1734 record_do_oop_call##nv_suffix(SpecializationStats::ik); \
1735 (closure)->do_oop##nv_suffix(p), \
1736 assert_is_in_closed_subset) \
1737 return size_helper(); \
1738 }
1739
1740 #ifndef SERIALGC
1741 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
1742 \
1743 int instanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \
1744 OopClosureType* closure) { \
1745 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
1746 /* header */ \
1747 if (closure->do_header()) { \
1748 obj->oop_iterate_header(closure); \
1749 } \
1750 /* instance variables */ \
1751 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
1752 obj, \
1753 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
1754 (closure)->do_oop##nv_suffix(p), \
1755 assert_is_in_closed_subset) \
1756 return size_helper(); \
1757 }
1758 #endif // !SERIALGC
1759
1760 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
1761 \
1762 int instanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \
1763 OopClosureType* closure, \
1764 MemRegion mr) { \
1765 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
1766 if (closure->do_header()) { \
1767 obj->oop_iterate_header(closure, mr); \
1768 } \
1769 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
1770 obj, mr.start(), mr.end(), \
1771 (closure)->do_oop##nv_suffix(p), \
1772 assert_is_in_closed_subset) \
1773 return size_helper(); \
1774 }
1775
1776 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
1777 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
1778 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
1779 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
1780 #ifndef SERIALGC
1781 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
1782 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
1783 #endif // !SERIALGC
1784
1785 int instanceKlass::oop_adjust_pointers(oop obj) {
1786 int size = size_helper();
1787 InstanceKlass_OOP_MAP_ITERATE( \
1788 obj, \
1789 MarkSweep::adjust_pointer(p), \
1790 assert_is_in)
1791 obj->adjust_header();
1792 return size;
1793 }
1794
1795 #ifndef SERIALGC
1796 void instanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
1797 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
1798 obj, \
1799 if (PSScavenge::should_scavenge(p)) { \
1800 pm->claim_or_forward_depth(p); \
1801 }, \
1802 assert_nothing )
1803 }
1804
1805 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
1806 InstanceKlass_OOP_MAP_ITERATE( \
1807 obj, \
1808 PSParallelCompact::adjust_pointer(p), \
1809 assert_nothing)
1810 return size_helper();
1811 }
1812
1813 #endif // SERIALGC
1814
1815 // This klass is alive but the implementor link is not followed/updated.
1816 // Subklass and sibling links are handled by Klass::follow_weak_klass_links
1817
1818 void instanceKlass::follow_weak_klass_links(
1819 BoolObjectClosure* is_alive, OopClosure* keep_alive) {
1820 assert(is_alive->do_object_b(as_klassOop()), "this oop should be live");
1821 if (ClassUnloading) {
1822 for (int i = 0; i < implementors_limit; i++) {
1823 klassOop impl = _implementors[i];
1824 if (impl == NULL) break; // no more in the list
1825 if (!is_alive->do_object_b(impl)) {
1826 // remove this guy from the list by overwriting him with the tail
1827 int lasti = --_nof_implementors;
1828 assert(lasti >= i && lasti < implementors_limit, "just checking");
1829 _implementors[i] = _implementors[lasti];
1830 _implementors[lasti] = NULL;
1831 --i; // rerun the loop at this index
1832 }
1833 }
1834 } else {
1835 for (int i = 0; i < implementors_limit; i++) {
1836 keep_alive->do_oop(&adr_implementors()[i]);
1837 }
1838 }
1839 Klass::follow_weak_klass_links(is_alive, keep_alive);
1840 }
1841
1842 void instanceKlass::remove_unshareable_info() {
1843 Klass::remove_unshareable_info();
1844 init_implementor();
1845 }
1846
1847 static void clear_all_breakpoints(methodOop m) {
1848 m->clear_all_breakpoints();
1849 }
1850
1851 void instanceKlass::release_C_heap_structures() {
1852 // Deallocate oop map cache
1853 if (_oop_map_cache != NULL) {
1854 delete _oop_map_cache;
1855 _oop_map_cache = NULL;
1856 }
1857
1858 // Deallocate JNI identifiers for jfieldIDs
1859 JNIid::deallocate(jni_ids());
1860 set_jni_ids(NULL);
1861
1862 jmethodID* jmeths = methods_jmethod_ids_acquire();
1863 if (jmeths != (jmethodID*)NULL) {
1864 release_set_methods_jmethod_ids(NULL);
1865 FreeHeap(jmeths);
1866 }
1867
1868 int* indices = methods_cached_itable_indices_acquire();
1869 if (indices != (int*)NULL) {
1870 release_set_methods_cached_itable_indices(NULL);
1871 FreeHeap(indices);
1872 }
1873
1874 // release dependencies
1875 nmethodBucket* b = _dependencies;
1876 _dependencies = NULL;
1877 while (b != NULL) {
1878 nmethodBucket* next = b->next();
1879 delete b;
1880 b = next;
1881 }
1882
1883 // Deallocate breakpoint records
1884 if (breakpoints() != 0x0) {
1885 methods_do(clear_all_breakpoints);
1886 assert(breakpoints() == 0x0, "should have cleared breakpoints");
1887 }
1888
1889 // deallocate information about previous versions
1890 if (_previous_versions != NULL) {
1891 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
1892 PreviousVersionNode * pv_node = _previous_versions->at(i);
1893 delete pv_node;
1894 }
1895 delete _previous_versions;
1896 _previous_versions = NULL;
1897 }
1898
1899 // deallocate the cached class file
1900 if (_cached_class_file_bytes != NULL) {
1901 os::free(_cached_class_file_bytes);
1902 _cached_class_file_bytes = NULL;
1903 _cached_class_file_len = 0;
1904 }
1905
1906 // Decrement symbol reference counts associated with the unloaded class.
1907 if (_name != NULL) _name->decrement_refcount();
1908 // unreference array name derived from this class name (arrays of an unloaded
1909 // class can't be referenced anymore).
1910 if (_array_name != NULL) _array_name->decrement_refcount();
1911 if (_source_file_name != NULL) _source_file_name->decrement_refcount();
1912 if (_source_debug_extension != NULL) _source_debug_extension->decrement_refcount();
1913 // walk constant pool and decrement symbol reference counts
1914 _constants->unreference_symbols();
1915 }
1916
1917 void instanceKlass::set_source_file_name(Symbol* n) {
1918 _source_file_name = n;
1919 if (_source_file_name != NULL) _source_file_name->increment_refcount();
1920 }
1921
1922 void instanceKlass::set_source_debug_extension(Symbol* n) {
1923 _source_debug_extension = n;
1924 if (_source_debug_extension != NULL) _source_debug_extension->increment_refcount();
1925 }
1926
1927 address instanceKlass::static_field_addr(int offset) {
1928 return (address)(offset + instanceMirrorKlass::offset_of_static_fields() + (intptr_t)java_mirror());
1929 }
1930
1931
1932 const char* instanceKlass::signature_name() const {
1933 const char* src = (const char*) (name()->as_C_string());
1934 const int src_length = (int)strlen(src);
1935 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
1936 int src_index = 0;
1937 int dest_index = 0;
1938 dest[dest_index++] = 'L';
1939 while (src_index < src_length) {
1940 dest[dest_index++] = src[src_index++];
1941 }
1942 dest[dest_index++] = ';';
1943 dest[dest_index] = '\0';
1944 return dest;
1945 }
1946
1947 // different verisons of is_same_class_package
1948 bool instanceKlass::is_same_class_package(klassOop class2) {
1949 klassOop class1 = as_klassOop();
1950 oop classloader1 = instanceKlass::cast(class1)->class_loader();
1951 Symbol* classname1 = Klass::cast(class1)->name();
1952
1953 if (Klass::cast(class2)->oop_is_objArray()) {
1954 class2 = objArrayKlass::cast(class2)->bottom_klass();
1955 }
1956 oop classloader2;
1957 if (Klass::cast(class2)->oop_is_instance()) {
1958 classloader2 = instanceKlass::cast(class2)->class_loader();
1959 } else {
1960 assert(Klass::cast(class2)->oop_is_typeArray(), "should be type array");
1961 classloader2 = NULL;
1962 }
1963 Symbol* classname2 = Klass::cast(class2)->name();
1964
1965 return instanceKlass::is_same_class_package(classloader1, classname1,
1966 classloader2, classname2);
1967 }
1968
1969 bool instanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
1970 klassOop class1 = as_klassOop();
1971 oop classloader1 = instanceKlass::cast(class1)->class_loader();
1972 Symbol* classname1 = Klass::cast(class1)->name();
1973
1974 return instanceKlass::is_same_class_package(classloader1, classname1,
1975 classloader2, classname2);
1976 }
1977
1978 // return true if two classes are in the same package, classloader
1979 // and classname information is enough to determine a class's package
1980 bool instanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
1981 oop class_loader2, Symbol* class_name2) {
1982 if (class_loader1 != class_loader2) {
1983 return false;
1984 } else if (class_name1 == class_name2) {
1985 return true; // skip painful bytewise comparison
1986 } else {
1987 ResourceMark rm;
1988
1989 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
1990 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
1991 // Otherwise, we just compare jbyte values between the strings.
1992 const jbyte *name1 = class_name1->base();
1993 const jbyte *name2 = class_name2->base();
1994
1995 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
1996 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
1997
1998 if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
1999 // One of the two doesn't have a package. Only return true
2000 // if the other one also doesn't have a package.
2001 return last_slash1 == last_slash2;
2002 } else {
2003 // Skip over '['s
2004 if (*name1 == '[') {
2005 do {
2006 name1++;
2007 } while (*name1 == '[');
2008 if (*name1 != 'L') {
2009 // Something is terribly wrong. Shouldn't be here.
2010 return false;
2011 }
2012 }
2013 if (*name2 == '[') {
2014 do {
2015 name2++;
2016 } while (*name2 == '[');
2017 if (*name2 != 'L') {
2018 // Something is terribly wrong. Shouldn't be here.
2019 return false;
2020 }
2021 }
2022
2023 // Check that package part is identical
2024 int length1 = last_slash1 - name1;
2025 int length2 = last_slash2 - name2;
2026
2027 return UTF8::equal(name1, length1, name2, length2);
2028 }
2029 }
2030 }
2031
2032 // Returns true iff super_method can be overridden by a method in targetclassname
2033 // See JSL 3rd edition 8.4.6.1
2034 // Assumes name-signature match
2035 // "this" is instanceKlass of super_method which must exist
2036 // note that the instanceKlass of the method in the targetclassname has not always been created yet
2037 bool instanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2038 // Private methods can not be overridden
2039 if (super_method->is_private()) {
2040 return false;
2041 }
2042 // If super method is accessible, then override
2043 if ((super_method->is_protected()) ||
2044 (super_method->is_public())) {
2045 return true;
2046 }
2047 // Package-private methods are not inherited outside of package
2048 assert(super_method->is_package_private(), "must be package private");
2049 return(is_same_class_package(targetclassloader(), targetclassname));
2050 }
2051
2052 /* defined for now in jvm.cpp, for historical reasons *--
2053 klassOop instanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2054 Symbol*& simple_name_result, TRAPS) {
2055 ...
2056 }
2057 */
2058
2059 // tell if two classes have the same enclosing class (at package level)
2060 bool instanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2061 klassOop class2_oop, TRAPS) {
2062 if (class2_oop == class1->as_klassOop()) return true;
2063 if (!Klass::cast(class2_oop)->oop_is_instance()) return false;
2064 instanceKlassHandle class2(THREAD, class2_oop);
2065
2066 // must be in same package before we try anything else
2067 if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2068 return false;
2069
2070 // As long as there is an outer1.getEnclosingClass,
2071 // shift the search outward.
2072 instanceKlassHandle outer1 = class1;
2073 for (;;) {
2074 // As we walk along, look for equalities between outer1 and class2.
2075 // Eventually, the walks will terminate as outer1 stops
2076 // at the top-level class around the original class.
2077 bool ignore_inner_is_member;
2078 klassOop next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2079 CHECK_false);
2080 if (next == NULL) break;
2081 if (next == class2()) return true;
2082 outer1 = instanceKlassHandle(THREAD, next);
2083 }
2084
2085 // Now do the same for class2.
2086 instanceKlassHandle outer2 = class2;
2087 for (;;) {
2088 bool ignore_inner_is_member;
2089 klassOop next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2090 CHECK_false);
2091 if (next == NULL) break;
2092 // Might as well check the new outer against all available values.
2093 if (next == class1()) return true;
2094 if (next == outer1()) return true;
2095 outer2 = instanceKlassHandle(THREAD, next);
2096 }
2097
2098 // If by this point we have not found an equality between the
2099 // two classes, we know they are in separate package members.
2100 return false;
2101 }
2102
2103
2104 jint instanceKlass::compute_modifier_flags(TRAPS) const {
2105 klassOop k = as_klassOop();
2106 jint access = access_flags().as_int();
2107
2108 // But check if it happens to be member class.
2109 typeArrayOop inner_class_list = inner_classes();
2110 int length = (inner_class_list == NULL) ? 0 : inner_class_list->length();
2111 assert (length % instanceKlass::inner_class_next_offset == 0, "just checking");
2112 if (length > 0) {
2113 typeArrayHandle inner_class_list_h(THREAD, inner_class_list);
2114 instanceKlassHandle ik(THREAD, k);
2115 for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) {
2116 int ioff = inner_class_list_h->ushort_at(
2117 i + instanceKlass::inner_class_inner_class_info_offset);
2118
2119 // Inner class attribute can be zero, skip it.
2120 // Strange but true: JVM spec. allows null inner class refs.
2121 if (ioff == 0) continue;
2122
2123 // only look at classes that are already loaded
2124 // since we are looking for the flags for our self.
2125 Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2126 if ((ik->name() == inner_name)) {
2127 // This is really a member class.
2128 access = inner_class_list_h->ushort_at(i + instanceKlass::inner_class_access_flags_offset);
2129 break;
2130 }
2131 }
2132 }
2133 // Remember to strip ACC_SUPER bit
2134 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2135 }
2136
2137 jint instanceKlass::jvmti_class_status() const {
2138 jint result = 0;
2139
2140 if (is_linked()) {
2141 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2142 }
2143
2144 if (is_initialized()) {
2145 assert(is_linked(), "Class status is not consistent");
2146 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2147 }
2148 if (is_in_error_state()) {
2149 result |= JVMTI_CLASS_STATUS_ERROR;
2150 }
2151 return result;
2152 }
2153
2154 methodOop instanceKlass::method_at_itable(klassOop holder, int index, TRAPS) {
2155 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2156 int method_table_offset_in_words = ioe->offset()/wordSize;
2157 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2158 / itableOffsetEntry::size();
2159
2160 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2161 // If the interface isn't implemented by the receiver class,
2162 // the VM should throw IncompatibleClassChangeError.
2163 if (cnt >= nof_interfaces) {
2164 THROW_0(vmSymbols::java_lang_IncompatibleClassChangeError());
2165 }
2166
2167 klassOop ik = ioe->interface_klass();
2168 if (ik == holder) break;
2169 }
2170
2171 itableMethodEntry* ime = ioe->first_method_entry(as_klassOop());
2172 methodOop m = ime[index].method();
2173 if (m == NULL) {
2174 THROW_0(vmSymbols::java_lang_AbstractMethodError());
2175 }
2176 return m;
2177 }
2178
2179 // On-stack replacement stuff
2180 void instanceKlass::add_osr_nmethod(nmethod* n) {
2181 // only one compilation can be active
2182 NEEDS_CLEANUP
2183 #ifdef COMPILER1
2184 // Get rid of the osr methods for the same bci
2185 if (C1ProfileInlining) {
2186 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
2187 if (inv != NULL && inv->is_in_use()) {
2188 inv->make_not_entrant();
2189 }
2190 }
2191 #endif
2192 // This is a short non-blocking critical region, so the no safepoint check is ok.
2193 OsrList_lock->lock_without_safepoint_check();
2194 assert(n->is_osr_method(), "wrong kind of nmethod");
2195 n->set_osr_link(osr_nmethods_head());
2196 set_osr_nmethods_head(n);
2197 // Raise the highest osr level if necessary
2198 if (TieredCompilation) {
2199 methodOop m = n->method();
2200 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2201 }
2202 // Remember to unlock again
2203 OsrList_lock->unlock();
2204
2205 // Get rid of the osr methods for the same bci that have lower levels.
2206 if (TieredCompilation) {
2207 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2208 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2209 if (inv != NULL && inv->is_in_use()) {
2210 inv->make_not_entrant();
2211 }
2212 }
2213 }
2214 }
2215
2216
2217 void instanceKlass::remove_osr_nmethod(nmethod* n) {
2218 // This is a short non-blocking critical region, so the no safepoint check is ok.
2219 OsrList_lock->lock_without_safepoint_check();
2220 assert(n->is_osr_method(), "wrong kind of nmethod");
2221 nmethod* last = NULL;
2222 nmethod* cur = osr_nmethods_head();
2223 int max_level = CompLevel_none; // Find the max comp level excluding n
2224 methodOop m = n->method();
2225 // Search for match
2226 while(cur != NULL && cur != n) {
2227 if (TieredCompilation) {
2228 // Find max level before n
2229 max_level = MAX2(max_level, cur->comp_level());
2230 }
2231 last = cur;
2232 cur = cur->osr_link();
2233 }
2234 nmethod* next = NULL;
2235 if (cur == n) {
2236 next = cur->osr_link();
2237 if (last == NULL) {
2238 // Remove first element
2239 set_osr_nmethods_head(next);
2240 } else {
2241 last->set_osr_link(next);
2242 }
2243 }
2244 n->set_osr_link(NULL);
2245 if (TieredCompilation) {
2246 cur = next;
2247 while (cur != NULL) {
2248 // Find max level after n
2249 max_level = MAX2(max_level, cur->comp_level());
2250 cur = cur->osr_link();
2251 }
2252 m->set_highest_osr_comp_level(max_level);
2253 }
2254 // Remember to unlock again
2255 OsrList_lock->unlock();
2256 }
2257
2258 nmethod* instanceKlass::lookup_osr_nmethod(const methodOop m, int bci, int comp_level, bool match_level) const {
2259 // This is a short non-blocking critical region, so the no safepoint check is ok.
2260 OsrList_lock->lock_without_safepoint_check();
2261 nmethod* osr = osr_nmethods_head();
2262 nmethod* best = NULL;
2263 while (osr != NULL) {
2264 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2265 // There can be a time when a c1 osr method exists but we are waiting
2266 // for a c2 version. When c2 completes its osr nmethod we will trash
2267 // the c1 version and only be able to find the c2 version. However
2268 // while we overflow in the c1 code at back branches we don't want to
2269 // try and switch to the same code as we are already running
2270
2271 if (osr->method() == m &&
2272 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2273 if (match_level) {
2274 if (osr->comp_level() == comp_level) {
2275 // Found a match - return it.
2276 OsrList_lock->unlock();
2277 return osr;
2278 }
2279 } else {
2280 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2281 if (osr->comp_level() == CompLevel_highest_tier) {
2282 // Found the best possible - return it.
2283 OsrList_lock->unlock();
2284 return osr;
2285 }
2286 best = osr;
2287 }
2288 }
2289 }
2290 osr = osr->osr_link();
2291 }
2292 OsrList_lock->unlock();
2293 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2294 return best;
2295 }
2296 return NULL;
2297 }
2298
2299 // -----------------------------------------------------------------------------------------------------
2300 #ifndef PRODUCT
2301
2302 // Printing
2303
2304 #define BULLET " - "
2305
2306 void FieldPrinter::do_field(fieldDescriptor* fd) {
2307 _st->print(BULLET);
2308 if (_obj == NULL) {
2309 fd->print_on(_st);
2310 _st->cr();
2311 } else {
2312 fd->print_on_for(_st, _obj);
2313 _st->cr();
2314 }
2315 }
2316
2317
2318 void instanceKlass::oop_print_on(oop obj, outputStream* st) {
2319 Klass::oop_print_on(obj, st);
2320
2321 if (as_klassOop() == SystemDictionary::String_klass()) {
2322 typeArrayOop value = java_lang_String::value(obj);
2323 juint offset = java_lang_String::offset(obj);
2324 juint length = java_lang_String::length(obj);
2325 if (value != NULL &&
2326 value->is_typeArray() &&
2327 offset <= (juint) value->length() &&
2328 offset + length <= (juint) value->length()) {
2329 st->print(BULLET"string: ");
2330 Handle h_obj(obj);
2331 java_lang_String::print(h_obj, st);
2332 st->cr();
2333 if (!WizardMode) return; // that is enough
2334 }
2335 }
2336
2337 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2338 FieldPrinter print_field(st, obj);
2339 do_nonstatic_fields(&print_field);
2340
2341 if (as_klassOop() == SystemDictionary::Class_klass()) {
2342 st->print(BULLET"signature: ");
2343 java_lang_Class::print_signature(obj, st);
2344 st->cr();
2345 klassOop mirrored_klass = java_lang_Class::as_klassOop(obj);
2346 st->print(BULLET"fake entry for mirror: ");
2347 mirrored_klass->print_value_on(st);
2348 st->cr();
2349 st->print(BULLET"fake entry resolved_constructor: ");
2350 methodOop ctor = java_lang_Class::resolved_constructor(obj);
2351 ctor->print_value_on(st);
2352 klassOop array_klass = java_lang_Class::array_klass(obj);
2353 st->cr();
2354 st->print(BULLET"fake entry for array: ");
2355 array_klass->print_value_on(st);
2356 st->cr();
2357 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2358 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2359 klassOop real_klass = java_lang_Class::as_klassOop(obj);
2360 if (real_klass != NULL && real_klass->klass_part()->oop_is_instance()) {
2361 instanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2362 }
2363 } else if (as_klassOop() == SystemDictionary::MethodType_klass()) {
2364 st->print(BULLET"signature: ");
2365 java_lang_invoke_MethodType::print_signature(obj, st);
2366 st->cr();
2367 }
2368 }
2369
2370 #endif //PRODUCT
2371
2372 void instanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2373 st->print("a ");
2374 name()->print_value_on(st);
2375 obj->print_address_on(st);
2376 if (as_klassOop() == SystemDictionary::String_klass()
2377 && java_lang_String::value(obj) != NULL) {
2378 ResourceMark rm;
2379 int len = java_lang_String::length(obj);
2380 int plen = (len < 24 ? len : 12);
2381 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2382 st->print(" = \"%s\"", str);
2383 if (len > plen)
2384 st->print("...[%d]", len);
2385 } else if (as_klassOop() == SystemDictionary::Class_klass()) {
2386 klassOop k = java_lang_Class::as_klassOop(obj);
2387 st->print(" = ");
2388 if (k != NULL) {
2389 k->print_value_on(st);
2390 } else {
2391 const char* tname = type2name(java_lang_Class::primitive_type(obj));
2392 st->print("%s", tname ? tname : "type?");
2393 }
2394 } else if (as_klassOop() == SystemDictionary::MethodType_klass()) {
2395 st->print(" = ");
2396 java_lang_invoke_MethodType::print_signature(obj, st);
2397 } else if (java_lang_boxing_object::is_instance(obj)) {
2398 st->print(" = ");
2399 java_lang_boxing_object::print(obj, st);
2400 }
2401 }
2402
2403 const char* instanceKlass::internal_name() const {
2404 return external_name();
2405 }
2406
2407 // Verification
2408
2409 class VerifyFieldClosure: public OopClosure {
2410 protected:
2411 template <class T> void do_oop_work(T* p) {
2412 guarantee(Universe::heap()->is_in_closed_subset(p), "should be in heap");
2413 oop obj = oopDesc::load_decode_heap_oop(p);
2414 if (!obj->is_oop_or_null()) {
2415 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
2416 Universe::print();
2417 guarantee(false, "boom");
2418 }
2419 }
2420 public:
2421 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
2422 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2423 };
2424
2425 void instanceKlass::oop_verify_on(oop obj, outputStream* st) {
2426 Klass::oop_verify_on(obj, st);
2427 VerifyFieldClosure blk;
2428 oop_oop_iterate(obj, &blk);
2429 }
2430
2431 // JNIid class for jfieldIDs only
2432 // Note to reviewers:
2433 // These JNI functions are just moved over to column 1 and not changed
2434 // in the compressed oops workspace.
2435 JNIid::JNIid(klassOop holder, int offset, JNIid* next) {
2436 _holder = holder;
2437 _offset = offset;
2438 _next = next;
2439 debug_only(_is_static_field_id = false;)
2440 }
2441
2442
2443 JNIid* JNIid::find(int offset) {
2444 JNIid* current = this;
2445 while (current != NULL) {
2446 if (current->offset() == offset) return current;
2447 current = current->next();
2448 }
2449 return NULL;
2450 }
2451
2452 void JNIid::oops_do(OopClosure* f) {
2453 for (JNIid* cur = this; cur != NULL; cur = cur->next()) {
2454 f->do_oop(cur->holder_addr());
2455 }
2456 }
2457
2458 void JNIid::deallocate(JNIid* current) {
2459 while (current != NULL) {
2460 JNIid* next = current->next();
2461 delete current;
2462 current = next;
2463 }
2464 }
2465
2466
2467 void JNIid::verify(klassOop holder) {
2468 int first_field_offset = instanceMirrorKlass::offset_of_static_fields();
2469 int end_field_offset;
2470 end_field_offset = first_field_offset + (instanceKlass::cast(holder)->static_field_size() * wordSize);
2471
2472 JNIid* current = this;
2473 while (current != NULL) {
2474 guarantee(current->holder() == holder, "Invalid klass in JNIid");
2475 #ifdef ASSERT
2476 int o = current->offset();
2477 if (current->is_static_field_id()) {
2478 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
2479 }
2480 #endif
2481 current = current->next();
2482 }
2483 }
2484
2485
2486 #ifdef ASSERT
2487 void instanceKlass::set_init_state(ClassState state) {
2488 bool good_state = as_klassOop()->is_shared() ? (_init_state <= state)
2489 : (_init_state < state);
2490 assert(good_state || state == allocated, "illegal state transition");
2491 _init_state = state;
2492 }
2493 #endif
2494
2495
2496 // RedefineClasses() support for previous versions:
2497
2498 // Add an information node that contains weak references to the
2499 // interesting parts of the previous version of the_class.
2500 // This is also where we clean out any unused weak references.
2501 // Note that while we delete nodes from the _previous_versions
2502 // array, we never delete the array itself until the klass is
2503 // unloaded. The has_been_redefined() query depends on that fact.
2504 //
2505 void instanceKlass::add_previous_version(instanceKlassHandle ikh,
2506 BitMap* emcp_methods, int emcp_method_count) {
2507 assert(Thread::current()->is_VM_thread(),
2508 "only VMThread can add previous versions");
2509
2510 if (_previous_versions == NULL) {
2511 // This is the first previous version so make some space.
2512 // Start with 2 elements under the assumption that the class
2513 // won't be redefined much.
2514 _previous_versions = new (ResourceObj::C_HEAP)
2515 GrowableArray<PreviousVersionNode *>(2, true);
2516 }
2517
2518 // RC_TRACE macro has an embedded ResourceMark
2519 RC_TRACE(0x00000100, ("adding previous version ref for %s @%d, EMCP_cnt=%d",
2520 ikh->external_name(), _previous_versions->length(), emcp_method_count));
2521 constantPoolHandle cp_h(ikh->constants());
2522 jobject cp_ref;
2523 if (cp_h->is_shared()) {
2524 // a shared ConstantPool requires a regular reference; a weak
2525 // reference would be collectible
2526 cp_ref = JNIHandles::make_global(cp_h);
2527 } else {
2528 cp_ref = JNIHandles::make_weak_global(cp_h);
2529 }
2530 PreviousVersionNode * pv_node = NULL;
2531 objArrayOop old_methods = ikh->methods();
2532
2533 if (emcp_method_count == 0) {
2534 // non-shared ConstantPool gets a weak reference
2535 pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), NULL);
2536 RC_TRACE(0x00000400,
2537 ("add: all methods are obsolete; flushing any EMCP weak refs"));
2538 } else {
2539 int local_count = 0;
2540 GrowableArray<jweak>* method_refs = new (ResourceObj::C_HEAP)
2541 GrowableArray<jweak>(emcp_method_count, true);
2542 for (int i = 0; i < old_methods->length(); i++) {
2543 if (emcp_methods->at(i)) {
2544 // this old method is EMCP so save a weak ref
2545 methodOop old_method = (methodOop) old_methods->obj_at(i);
2546 methodHandle old_method_h(old_method);
2547 jweak method_ref = JNIHandles::make_weak_global(old_method_h);
2548 method_refs->append(method_ref);
2549 if (++local_count >= emcp_method_count) {
2550 // no more EMCP methods so bail out now
2551 break;
2552 }
2553 }
2554 }
2555 // non-shared ConstantPool gets a weak reference
2556 pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), method_refs);
2557 }
2558
2559 _previous_versions->append(pv_node);
2560
2561 // Using weak references allows the interesting parts of previous
2562 // classes to be GC'ed when they are no longer needed. Since the
2563 // caller is the VMThread and we are at a safepoint, this is a good
2564 // time to clear out unused weak references.
2565
2566 RC_TRACE(0x00000400, ("add: previous version length=%d",
2567 _previous_versions->length()));
2568
2569 // skip the last entry since we just added it
2570 for (int i = _previous_versions->length() - 2; i >= 0; i--) {
2571 // check the previous versions array for a GC'ed weak refs
2572 pv_node = _previous_versions->at(i);
2573 cp_ref = pv_node->prev_constant_pool();
2574 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
2575 if (cp_ref == NULL) {
2576 delete pv_node;
2577 _previous_versions->remove_at(i);
2578 // Since we are traversing the array backwards, we don't have to
2579 // do anything special with the index.
2580 continue; // robustness
2581 }
2582
2583 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2584 if (cp == NULL) {
2585 // this entry has been GC'ed so remove it
2586 delete pv_node;
2587 _previous_versions->remove_at(i);
2588 // Since we are traversing the array backwards, we don't have to
2589 // do anything special with the index.
2590 continue;
2591 } else {
2592 RC_TRACE(0x00000400, ("add: previous version @%d is alive", i));
2593 }
2594
2595 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2596 if (method_refs != NULL) {
2597 RC_TRACE(0x00000400, ("add: previous methods length=%d",
2598 method_refs->length()));
2599 for (int j = method_refs->length() - 1; j >= 0; j--) {
2600 jweak method_ref = method_refs->at(j);
2601 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
2602 if (method_ref == NULL) {
2603 method_refs->remove_at(j);
2604 // Since we are traversing the array backwards, we don't have to
2605 // do anything special with the index.
2606 continue; // robustness
2607 }
2608
2609 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2610 if (method == NULL || emcp_method_count == 0) {
2611 // This method entry has been GC'ed or the current
2612 // RedefineClasses() call has made all methods obsolete
2613 // so remove it.
2614 JNIHandles::destroy_weak_global(method_ref);
2615 method_refs->remove_at(j);
2616 } else {
2617 // RC_TRACE macro has an embedded ResourceMark
2618 RC_TRACE(0x00000400,
2619 ("add: %s(%s): previous method @%d in version @%d is alive",
2620 method->name()->as_C_string(), method->signature()->as_C_string(),
2621 j, i));
2622 }
2623 }
2624 }
2625 }
2626
2627 int obsolete_method_count = old_methods->length() - emcp_method_count;
2628
2629 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
2630 _previous_versions->length() > 1) {
2631 // We have a mix of obsolete and EMCP methods. If there is more
2632 // than the previous version that we just added, then we have to
2633 // clear out any matching EMCP method entries the hard way.
2634 int local_count = 0;
2635 for (int i = 0; i < old_methods->length(); i++) {
2636 if (!emcp_methods->at(i)) {
2637 // only obsolete methods are interesting
2638 methodOop old_method = (methodOop) old_methods->obj_at(i);
2639 Symbol* m_name = old_method->name();
2640 Symbol* m_signature = old_method->signature();
2641
2642 // skip the last entry since we just added it
2643 for (int j = _previous_versions->length() - 2; j >= 0; j--) {
2644 // check the previous versions array for a GC'ed weak refs
2645 pv_node = _previous_versions->at(j);
2646 cp_ref = pv_node->prev_constant_pool();
2647 assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
2648 if (cp_ref == NULL) {
2649 delete pv_node;
2650 _previous_versions->remove_at(j);
2651 // Since we are traversing the array backwards, we don't have to
2652 // do anything special with the index.
2653 continue; // robustness
2654 }
2655
2656 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2657 if (cp == NULL) {
2658 // this entry has been GC'ed so remove it
2659 delete pv_node;
2660 _previous_versions->remove_at(j);
2661 // Since we are traversing the array backwards, we don't have to
2662 // do anything special with the index.
2663 continue;
2664 }
2665
2666 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2667 if (method_refs == NULL) {
2668 // We have run into a PreviousVersion generation where
2669 // all methods were made obsolete during that generation's
2670 // RedefineClasses() operation. At the time of that
2671 // operation, all EMCP methods were flushed so we don't
2672 // have to go back any further.
2673 //
2674 // A NULL method_refs is different than an empty method_refs.
2675 // We cannot infer any optimizations about older generations
2676 // from an empty method_refs for the current generation.
2677 break;
2678 }
2679
2680 for (int k = method_refs->length() - 1; k >= 0; k--) {
2681 jweak method_ref = method_refs->at(k);
2682 assert(method_ref != NULL,
2683 "weak method ref was unexpectedly cleared");
2684 if (method_ref == NULL) {
2685 method_refs->remove_at(k);
2686 // Since we are traversing the array backwards, we don't
2687 // have to do anything special with the index.
2688 continue; // robustness
2689 }
2690
2691 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2692 if (method == NULL) {
2693 // this method entry has been GC'ed so skip it
2694 JNIHandles::destroy_weak_global(method_ref);
2695 method_refs->remove_at(k);
2696 continue;
2697 }
2698
2699 if (method->name() == m_name &&
2700 method->signature() == m_signature) {
2701 // The current RedefineClasses() call has made all EMCP
2702 // versions of this method obsolete so mark it as obsolete
2703 // and remove the weak ref.
2704 RC_TRACE(0x00000400,
2705 ("add: %s(%s): flush obsolete method @%d in version @%d",
2706 m_name->as_C_string(), m_signature->as_C_string(), k, j));
2707
2708 method->set_is_obsolete();
2709 JNIHandles::destroy_weak_global(method_ref);
2710 method_refs->remove_at(k);
2711 break;
2712 }
2713 }
2714
2715 // The previous loop may not find a matching EMCP method, but
2716 // that doesn't mean that we can optimize and not go any
2717 // further back in the PreviousVersion generations. The EMCP
2718 // method for this generation could have already been GC'ed,
2719 // but there still may be an older EMCP method that has not
2720 // been GC'ed.
2721 }
2722
2723 if (++local_count >= obsolete_method_count) {
2724 // no more obsolete methods so bail out now
2725 break;
2726 }
2727 }
2728 }
2729 }
2730 } // end add_previous_version()
2731
2732
2733 // Determine if instanceKlass has a previous version.
2734 bool instanceKlass::has_previous_version() const {
2735 if (_previous_versions == NULL) {
2736 // no previous versions array so answer is easy
2737 return false;
2738 }
2739
2740 for (int i = _previous_versions->length() - 1; i >= 0; i--) {
2741 // Check the previous versions array for an info node that hasn't
2742 // been GC'ed
2743 PreviousVersionNode * pv_node = _previous_versions->at(i);
2744
2745 jobject cp_ref = pv_node->prev_constant_pool();
2746 assert(cp_ref != NULL, "cp reference was unexpectedly cleared");
2747 if (cp_ref == NULL) {
2748 continue; // robustness
2749 }
2750
2751 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2752 if (cp != NULL) {
2753 // we have at least one previous version
2754 return true;
2755 }
2756
2757 // We don't have to check the method refs. If the constant pool has
2758 // been GC'ed then so have the methods.
2759 }
2760
2761 // all of the underlying nodes' info has been GC'ed
2762 return false;
2763 } // end has_previous_version()
2764
2765 methodOop instanceKlass::method_with_idnum(int idnum) {
2766 methodOop m = NULL;
2767 if (idnum < methods()->length()) {
2768 m = (methodOop) methods()->obj_at(idnum);
2769 }
2770 if (m == NULL || m->method_idnum() != idnum) {
2771 for (int index = 0; index < methods()->length(); ++index) {
2772 m = (methodOop) methods()->obj_at(index);
2773 if (m->method_idnum() == idnum) {
2774 return m;
2775 }
2776 }
2777 }
2778 return m;
2779 }
2780
2781
2782 // Set the annotation at 'idnum' to 'anno'.
2783 // We don't want to create or extend the array if 'anno' is NULL, since that is the
2784 // default value. However, if the array exists and is long enough, we must set NULL values.
2785 void instanceKlass::set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p) {
2786 objArrayOop md = *md_p;
2787 if (md != NULL && md->length() > idnum) {
2788 md->obj_at_put(idnum, anno);
2789 } else if (anno != NULL) {
2790 // create the array
2791 int length = MAX2(idnum+1, (int)_idnum_allocated_count);
2792 md = oopFactory::new_system_objArray(length, Thread::current());
2793 if (*md_p != NULL) {
2794 // copy the existing entries
2795 for (int index = 0; index < (*md_p)->length(); index++) {
2796 md->obj_at_put(index, (*md_p)->obj_at(index));
2797 }
2798 }
2799 set_annotations(md, md_p);
2800 md->obj_at_put(idnum, anno);
2801 } // if no array and idnum isn't included there is nothing to do
2802 }
2803
2804 // Construct a PreviousVersionNode entry for the array hung off
2805 // the instanceKlass.
2806 PreviousVersionNode::PreviousVersionNode(jobject prev_constant_pool,
2807 bool prev_cp_is_weak, GrowableArray<jweak>* prev_EMCP_methods) {
2808
2809 _prev_constant_pool = prev_constant_pool;
2810 _prev_cp_is_weak = prev_cp_is_weak;
2811 _prev_EMCP_methods = prev_EMCP_methods;
2812 }
2813
2814
2815 // Destroy a PreviousVersionNode
2816 PreviousVersionNode::~PreviousVersionNode() {
2817 if (_prev_constant_pool != NULL) {
2818 if (_prev_cp_is_weak) {
2819 JNIHandles::destroy_weak_global(_prev_constant_pool);
2820 } else {
2821 JNIHandles::destroy_global(_prev_constant_pool);
2822 }
2823 }
2824
2825 if (_prev_EMCP_methods != NULL) {
2826 for (int i = _prev_EMCP_methods->length() - 1; i >= 0; i--) {
2827 jweak method_ref = _prev_EMCP_methods->at(i);
2828 if (method_ref != NULL) {
2829 JNIHandles::destroy_weak_global(method_ref);
2830 }
2831 }
2832 delete _prev_EMCP_methods;
2833 }
2834 }
2835
2836
2837 // Construct a PreviousVersionInfo entry
2838 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
2839 _prev_constant_pool_handle = constantPoolHandle(); // NULL handle
2840 _prev_EMCP_method_handles = NULL;
2841
2842 jobject cp_ref = pv_node->prev_constant_pool();
2843 assert(cp_ref != NULL, "constant pool ref was unexpectedly cleared");
2844 if (cp_ref == NULL) {
2845 return; // robustness
2846 }
2847
2848 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
2849 if (cp == NULL) {
2850 // Weak reference has been GC'ed. Since the constant pool has been
2851 // GC'ed, the methods have also been GC'ed.
2852 return;
2853 }
2854
2855 // make the constantPoolOop safe to return
2856 _prev_constant_pool_handle = constantPoolHandle(cp);
2857
2858 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
2859 if (method_refs == NULL) {
2860 // the instanceKlass did not have any EMCP methods
2861 return;
2862 }
2863
2864 _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
2865
2866 int n_methods = method_refs->length();
2867 for (int i = 0; i < n_methods; i++) {
2868 jweak method_ref = method_refs->at(i);
2869 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
2870 if (method_ref == NULL) {
2871 continue; // robustness
2872 }
2873
2874 methodOop method = (methodOop)JNIHandles::resolve(method_ref);
2875 if (method == NULL) {
2876 // this entry has been GC'ed so skip it
2877 continue;
2878 }
2879
2880 // make the methodOop safe to return
2881 _prev_EMCP_method_handles->append(methodHandle(method));
2882 }
2883 }
2884
2885
2886 // Destroy a PreviousVersionInfo
2887 PreviousVersionInfo::~PreviousVersionInfo() {
2888 // Since _prev_EMCP_method_handles is not C-heap allocated, we
2889 // don't have to delete it.
2890 }
2891
2892
2893 // Construct a helper for walking the previous versions array
2894 PreviousVersionWalker::PreviousVersionWalker(instanceKlass *ik) {
2895 _previous_versions = ik->previous_versions();
2896 _current_index = 0;
2897 // _hm needs no initialization
2898 _current_p = NULL;
2899 }
2900
2901
2902 // Destroy a PreviousVersionWalker
2903 PreviousVersionWalker::~PreviousVersionWalker() {
2904 // Delete the current info just in case the caller didn't walk to
2905 // the end of the previous versions list. No harm if _current_p is
2906 // already NULL.
2907 delete _current_p;
2908
2909 // When _hm is destroyed, all the Handles returned in
2910 // PreviousVersionInfo objects will be destroyed.
2911 // Also, after this destructor is finished it will be
2912 // safe to delete the GrowableArray allocated in the
2913 // PreviousVersionInfo objects.
2914 }
2915
2916
2917 // Return the interesting information for the next previous version
2918 // of the klass. Returns NULL if there are no more previous versions.
2919 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
2920 if (_previous_versions == NULL) {
2921 // no previous versions so nothing to return
2922 return NULL;
2923 }
2924
2925 delete _current_p; // cleanup the previous info for the caller
2926 _current_p = NULL; // reset to NULL so we don't delete same object twice
2927
2928 int length = _previous_versions->length();
2929
2930 while (_current_index < length) {
2931 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
2932 PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP)
2933 PreviousVersionInfo(pv_node);
2934
2935 constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
2936 if (cp_h.is_null()) {
2937 delete pv_info;
2938
2939 // The underlying node's info has been GC'ed so try the next one.
2940 // We don't have to check the methods. If the constant pool has
2941 // GC'ed then so have the methods.
2942 continue;
2943 }
2944
2945 // Found a node with non GC'ed info so return it. The caller will
2946 // need to delete pv_info when they are done with it.
2947 _current_p = pv_info;
2948 return pv_info;
2949 }
2950
2951 // all of the underlying nodes' info has been GC'ed
2952 return NULL;
2953 } // end next_previous_version()