1 /*
2 * Copyright (c) 1997, 2018, 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 "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/javaClasses.hpp"
32 #include "classfile/moduleEntry.hpp"
33 #include "classfile/systemDictionary.hpp"
34 #include "classfile/systemDictionaryShared.hpp"
35 #include "classfile/verifier.hpp"
36 #include "classfile/vmSymbols.hpp"
37 #include "code/dependencyContext.hpp"
38 #include "compiler/compileBroker.hpp"
39 #include "gc/shared/collectedHeap.inline.hpp"
40 #include "gc/shared/specialized_oop_closures.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "interpreter/rewriter.hpp"
43 #include "jvmtifiles/jvmti.h"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/heapInspection.hpp"
48 #include "memory/iterator.inline.hpp"
49 #include "memory/metadataFactory.hpp"
50 #include "memory/metaspaceClosure.hpp"
51 #include "memory/metaspaceShared.hpp"
52 #include "memory/oopFactory.hpp"
53 #include "memory/resourceArea.hpp"
54 #include "oops/fieldStreams.hpp"
55 #include "oops/instanceClassLoaderKlass.hpp"
56 #include "oops/instanceKlass.inline.hpp"
57 #include "oops/instanceMirrorKlass.hpp"
58 #include "oops/instanceOop.hpp"
59 #include "oops/klass.inline.hpp"
60 #include "oops/method.hpp"
61 #include "oops/oop.inline.hpp"
62 #include "oops/symbol.hpp"
63 #include "oops/valueKlass.hpp"
64 #include "prims/jvmtiExport.hpp"
65 #include "prims/jvmtiRedefineClasses.hpp"
66 #include "prims/jvmtiThreadState.hpp"
67 #include "prims/methodComparator.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/fieldDescriptor.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/javaCalls.hpp"
72 #include "runtime/mutexLocker.hpp"
73 #include "runtime/orderAccess.inline.hpp"
74 #include "runtime/thread.inline.hpp"
75 #include "services/classLoadingService.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/dtrace.hpp"
78 #include "utilities/macros.hpp"
79 #include "utilities/stringUtils.hpp"
80 #ifdef COMPILER1
81 #include "c1/c1_Compiler.hpp"
82 #endif
83
84 #ifdef DTRACE_ENABLED
85
86
87 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
88 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
89 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
90 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
91 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
92 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
93 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
94 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
95 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
96 { \
97 char* data = NULL; \
98 int len = 0; \
99 Symbol* clss_name = name(); \
100 if (clss_name != NULL) { \
101 data = (char*)clss_name->bytes(); \
102 len = clss_name->utf8_length(); \
103 } \
104 HOTSPOT_CLASS_INITIALIZATION_##type( \
105 data, len, (void*)class_loader(), thread_type); \
106 }
107
108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
109 { \
110 char* data = NULL; \
111 int len = 0; \
112 Symbol* clss_name = name(); \
113 if (clss_name != NULL) { \
114 data = (char*)clss_name->bytes(); \
115 len = clss_name->utf8_length(); \
116 } \
117 HOTSPOT_CLASS_INITIALIZATION_##type( \
118 data, len, (void*)class_loader(), thread_type, wait); \
119 }
120
121 #else // ndef DTRACE_ENABLED
122
123 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
125
126 #endif // ndef DTRACE_ENABLED
127
128 volatile int InstanceKlass::_total_instanceKlass_count = 0;
129
130 static inline bool is_class_loader(const Symbol* class_name,
131 const ClassFileParser& parser) {
132 assert(class_name != NULL, "invariant");
133
134 if (class_name == vmSymbols::java_lang_ClassLoader()) {
135 return true;
136 }
137
138 if (SystemDictionary::ClassLoader_klass_loaded()) {
139 const Klass* const super_klass = parser.super_klass();
140 if (super_klass != NULL) {
141 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
142 return true;
143 }
144 }
145 }
146 return false;
147 }
148
149 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
150 const int size = InstanceKlass::size(parser.vtable_size(),
151 parser.itable_size(),
152 nonstatic_oop_map_size(parser.total_oop_map_count()),
153 parser.is_interface(),
154 parser.is_anonymous(),
155 should_store_fingerprint(parser.is_anonymous()),
156 parser.has_value_fields() ? parser.java_fields_count() : 0,
157 parser.is_value_type());
158
159 const Symbol* const class_name = parser.class_name();
160 assert(class_name != NULL, "invariant");
161 ClassLoaderData* loader_data = parser.loader_data();
162 assert(loader_data != NULL, "invariant");
163
164 InstanceKlass* ik;
165
166 // Allocation
167 if (REF_NONE == parser.reference_type()) {
168 if (class_name == vmSymbols::java_lang_Class()) {
169 // mirror
170 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
171 } else if (is_class_loader(class_name, parser)) {
172 // class loader
173 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
174 } else if (parser.is_value_type()) {
175 // value type
176 ik = new (loader_data, size, THREAD) ValueKlass(parser);
177 } else {
178 // normal
179 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
180 }
181 } else {
182 // reference
183 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
184 }
185
186 // Check for pending exception before adding to the loader data and incrementing
187 // class count. Can get OOM here.
188 if (HAS_PENDING_EXCEPTION) {
189 return NULL;
190 }
191
192 assert(ik != NULL, "invariant");
193
194 const bool publicize = !parser.is_internal();
195 #ifdef ASSERT
196 assert(ik->size() == size, "");
197 ik->bounds_check((address) ik->start_of_vtable(), false, size);
198 ik->bounds_check((address) ik->start_of_itable(), false, size);
199 ik->bounds_check((address) ik->end_of_itable(), true, size);
200 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
201 #endif //ASSERT
202
203 // Add all classes to our internal class loader list here,
204 // including classes in the bootstrap (NULL) class loader.
205 loader_data->add_class(ik, publicize);
206 Atomic::inc(&_total_instanceKlass_count);
207
208 return ik;
209 }
210
211 #ifndef PRODUCT
212 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
213 const char* bad = NULL;
214 address end = NULL;
215 if (addr < (address)this) {
216 bad = "before";
217 } else if (addr == (address)this) {
218 if (edge_ok) return true;
219 bad = "just before";
220 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
221 if (edge_ok) return true;
222 bad = "just after";
223 } else if (addr > end) {
224 bad = "after";
225 } else {
226 return true;
227 }
228 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
229 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
230 Verbose = WizardMode = true; this->print(); //@@
231 return false;
232 }
233 #endif //PRODUCT
234
235 // copy method ordering from resource area to Metaspace
236 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
237 if (m != NULL) {
238 // allocate a new array and copy contents (memcpy?)
239 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
240 for (int i = 0; i < m->length(); i++) {
241 _method_ordering->at_put(i, m->at(i));
242 }
243 } else {
244 _method_ordering = Universe::the_empty_int_array();
245 }
246 }
247
248 // create a new array of vtable_indices for default methods
249 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
250 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
251 assert(default_vtable_indices() == NULL, "only create once");
252 set_default_vtable_indices(vtable_indices);
253 return vtable_indices;
254 }
255
256 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
257 _static_field_size(parser.static_field_size()),
258 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
259 _itable_len(parser.itable_size()),
260 _reference_type(parser.reference_type()),
261 _extra_flags(0) {
262 set_vtable_length(parser.vtable_size());
263 set_kind(kind);
264 set_access_flags(parser.access_flags());
265 set_is_anonymous(parser.is_anonymous());
266 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
267 false));
268 if (parser.has_value_fields()) {
269 set_has_value_fields();
270 }
271 _java_fields_count = parser.java_fields_count();
272
273 assert(NULL == _methods, "underlying memory not zeroed?");
274 assert(is_instance_klass(), "is layout incorrect?");
275 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
276 }
277
278 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
279 Array<Method*>* methods) {
280 if (methods != NULL && methods != Universe::the_empty_method_array() &&
281 !methods->is_shared()) {
282 for (int i = 0; i < methods->length(); i++) {
283 Method* method = methods->at(i);
284 if (method == NULL) continue; // maybe null if error processing
285 // Only want to delete methods that are not executing for RedefineClasses.
286 // The previous version will point to them so they're not totally dangling
287 assert (!method->on_stack(), "shouldn't be called with methods on stack");
288 MetadataFactory::free_metadata(loader_data, method);
289 }
290 MetadataFactory::free_array<Method*>(loader_data, methods);
291 }
292 }
293
294 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
295 const Klass* super_klass,
296 Array<Klass*>* local_interfaces,
297 Array<Klass*>* transitive_interfaces) {
298 // Only deallocate transitive interfaces if not empty, same as super class
299 // or same as local interfaces. See code in parseClassFile.
300 Array<Klass*>* ti = transitive_interfaces;
301 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
302 // check that the interfaces don't come from super class
303 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
304 InstanceKlass::cast(super_klass)->transitive_interfaces();
305 if (ti != sti && ti != NULL && !ti->is_shared()) {
306 MetadataFactory::free_array<Klass*>(loader_data, ti);
307 }
308 }
309
310 // local interfaces can be empty
311 if (local_interfaces != Universe::the_empty_klass_array() &&
312 local_interfaces != NULL && !local_interfaces->is_shared()) {
313 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
314 }
315 }
316
317 // This function deallocates the metadata and C heap pointers that the
318 // InstanceKlass points to.
319 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
320
321 // Orphan the mirror first, CMS thinks it's still live.
322 if (java_mirror() != NULL) {
323 java_lang_Class::set_klass(java_mirror(), NULL);
324 }
325
326 // Also remove mirror from handles
327 loader_data->remove_handle(_java_mirror);
328
329 // Need to take this class off the class loader data list.
330 loader_data->remove_class(this);
331
332 // The array_klass for this class is created later, after error handling.
333 // For class redefinition, we keep the original class so this scratch class
334 // doesn't have an array class. Either way, assert that there is nothing
335 // to deallocate.
336 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
337
338 // Release C heap allocated data that this might point to, which includes
339 // reference counting symbol names.
340 release_C_heap_structures();
341
342 deallocate_methods(loader_data, methods());
343 set_methods(NULL);
344
345 if (method_ordering() != NULL &&
346 method_ordering() != Universe::the_empty_int_array() &&
347 !method_ordering()->is_shared()) {
348 MetadataFactory::free_array<int>(loader_data, method_ordering());
349 }
350 set_method_ordering(NULL);
351
352 // default methods can be empty
353 if (default_methods() != NULL &&
354 default_methods() != Universe::the_empty_method_array() &&
355 !default_methods()->is_shared()) {
356 MetadataFactory::free_array<Method*>(loader_data, default_methods());
357 }
358 // Do NOT deallocate the default methods, they are owned by superinterfaces.
359 set_default_methods(NULL);
360
361 // default methods vtable indices can be empty
362 if (default_vtable_indices() != NULL &&
363 !default_vtable_indices()->is_shared()) {
364 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
365 }
366 set_default_vtable_indices(NULL);
367
368
369 // This array is in Klass, but remove it with the InstanceKlass since
370 // this place would be the only caller and it can share memory with transitive
371 // interfaces.
372 if (secondary_supers() != NULL &&
373 secondary_supers() != Universe::the_empty_klass_array() &&
374 secondary_supers() != transitive_interfaces() &&
375 !secondary_supers()->is_shared()) {
376 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
377 }
378 set_secondary_supers(NULL);
379
380 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
381 set_transitive_interfaces(NULL);
382 set_local_interfaces(NULL);
383
384 if (fields() != NULL && !fields()->is_shared()) {
385 MetadataFactory::free_array<jushort>(loader_data, fields());
386 }
387 set_fields(NULL, 0);
388
389 // If a method from a redefined class is using this constant pool, don't
390 // delete it, yet. The new class's previous version will point to this.
391 if (constants() != NULL) {
392 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
393 if (!constants()->is_shared()) {
394 MetadataFactory::free_metadata(loader_data, constants());
395 }
396 // Delete any cached resolution errors for the constant pool
397 SystemDictionary::delete_resolution_error(constants());
398
399 set_constants(NULL);
400 }
401
402 if (inner_classes() != NULL &&
403 inner_classes() != Universe::the_empty_short_array() &&
404 !inner_classes()->is_shared()) {
405 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
406 }
407 set_inner_classes(NULL);
408
409 // We should deallocate the Annotations instance if it's not in shared spaces.
410 if (annotations() != NULL && !annotations()->is_shared()) {
411 MetadataFactory::free_metadata(loader_data, annotations());
412 }
413 set_annotations(NULL);
414 }
415
416 bool InstanceKlass::should_be_initialized() const {
417 return !is_initialized();
418 }
419
420 klassItable InstanceKlass::itable() const {
421 return klassItable(const_cast<InstanceKlass*>(this));
422 }
423
424 void InstanceKlass::eager_initialize(Thread *thread) {
425 if (!EagerInitialization) return;
426
427 if (this->is_not_initialized()) {
428 // abort if the the class has a class initializer
429 if (this->class_initializer() != NULL) return;
430
431 // abort if it is java.lang.Object (initialization is handled in genesis)
432 Klass* super_klass = super();
433 if (super_klass == NULL) return;
434
435 // abort if the super class should be initialized
436 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
437
438 // call body to expose the this pointer
439 eager_initialize_impl();
440 }
441 }
442
443 // JVMTI spec thinks there are signers and protection domain in the
444 // instanceKlass. These accessors pretend these fields are there.
445 // The hprof specification also thinks these fields are in InstanceKlass.
446 oop InstanceKlass::protection_domain() const {
447 // return the protection_domain from the mirror
448 return java_lang_Class::protection_domain(java_mirror());
449 }
450
451 // To remove these from requires an incompatible change and CCC request.
452 objArrayOop InstanceKlass::signers() const {
453 // return the signers from the mirror
454 return java_lang_Class::signers(java_mirror());
455 }
456
457 oop InstanceKlass::init_lock() const {
458 // return the init lock from the mirror
459 oop lock = java_lang_Class::init_lock(java_mirror());
460 // Prevent reordering with any access of initialization state
461 OrderAccess::loadload();
462 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
463 "only fully initialized state can have a null lock");
464 return lock;
465 }
466
467 // Set the initialization lock to null so the object can be GC'ed. Any racing
468 // threads to get this lock will see a null lock and will not lock.
469 // That's okay because they all check for initialized state after getting
470 // the lock and return.
471 void InstanceKlass::fence_and_clear_init_lock() {
472 // make sure previous stores are all done, notably the init_state.
473 OrderAccess::storestore();
474 java_lang_Class::set_init_lock(java_mirror(), NULL);
475 assert(!is_not_initialized(), "class must be initialized now");
476 }
477
478 void InstanceKlass::eager_initialize_impl() {
479 EXCEPTION_MARK;
480 HandleMark hm(THREAD);
481 Handle h_init_lock(THREAD, init_lock());
482 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
483
484 // abort if someone beat us to the initialization
485 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
486
487 ClassState old_state = init_state();
488 link_class_impl(true, THREAD);
489 if (HAS_PENDING_EXCEPTION) {
490 CLEAR_PENDING_EXCEPTION;
491 // Abort if linking the class throws an exception.
492
493 // Use a test to avoid redundantly resetting the state if there's
494 // no change. Set_init_state() asserts that state changes make
495 // progress, whereas here we might just be spinning in place.
496 if (old_state != _init_state)
497 set_init_state(old_state);
498 } else {
499 // linking successfull, mark class as initialized
500 set_init_state(fully_initialized);
501 fence_and_clear_init_lock();
502 // trace
503 if (log_is_enabled(Info, class, init)) {
504 ResourceMark rm(THREAD);
505 log_info(class, init)("[Initialized %s without side effects]", external_name());
506 }
507 }
508 }
509
510
511 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
512 // process. The step comments refers to the procedure described in that section.
513 // Note: implementation moved to static method to expose the this pointer.
514 void InstanceKlass::initialize(TRAPS) {
515 if (this->should_be_initialized()) {
516 initialize_impl(CHECK);
517 // Note: at this point the class may be initialized
518 // OR it may be in the state of being initialized
519 // in case of recursive initialization!
520 } else {
521 assert(is_initialized(), "sanity check");
522 }
523 }
524
525
526 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
527 // 1) Verify the bytecodes
528 Verifier::Mode mode =
529 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
530 return Verifier::verify(this, mode, should_verify_class(), THREAD);
531 }
532
533
534 // Used exclusively by the shared spaces dump mechanism to prevent
535 // classes mapped into the shared regions in new VMs from appearing linked.
536
537 void InstanceKlass::unlink_class() {
538 assert(is_linked(), "must be linked");
539 _init_state = loaded;
540 }
541
542 void InstanceKlass::link_class(TRAPS) {
543 assert(is_loaded(), "must be loaded");
544 if (!is_linked()) {
545 link_class_impl(true, CHECK);
546 }
547 }
548
549 // Called to verify that a class can link during initialization, without
550 // throwing a VerifyError.
551 bool InstanceKlass::link_class_or_fail(TRAPS) {
552 assert(is_loaded(), "must be loaded");
553 if (!is_linked()) {
554 link_class_impl(false, CHECK_false);
555 }
556 return is_linked();
557 }
558
559 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
560 if (DumpSharedSpaces && is_in_error_state()) {
561 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
562 // the class has failed verification. Throwing the NoClassDefFoundError here is just
563 // a convenient way to stop repeat attempts to verify the same (bad) class.
564 //
565 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
566 // if we are executing Java code. This is not a problem for CDS dumping phase since
567 // it doesn't execute any Java code.
568 ResourceMark rm(THREAD);
569 Exceptions::fthrow(THREAD_AND_LOCATION,
570 vmSymbols::java_lang_NoClassDefFoundError(),
571 "Class %s, or one of its supertypes, failed class initialization",
572 external_name());
573 return false;
574 }
575 // return if already verified
576 if (is_linked()) {
577 return true;
578 }
579
580 // Timing
581 // timer handles recursion
582 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
583 JavaThread* jt = (JavaThread*)THREAD;
584
585 // link super class before linking this class
586 Klass* super_klass = super();
587 if (super_klass != NULL) {
588 if (super_klass->is_interface()) { // check if super class is an interface
589 ResourceMark rm(THREAD);
590 Exceptions::fthrow(
591 THREAD_AND_LOCATION,
592 vmSymbols::java_lang_IncompatibleClassChangeError(),
593 "class %s has interface %s as super class",
594 external_name(),
595 super_klass->external_name()
596 );
597 return false;
598 }
599
600 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
601 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
602 }
603
604 // link all interfaces implemented by this class before linking this class
605 Array<Klass*>* interfaces = local_interfaces();
606 int num_interfaces = interfaces->length();
607 for (int index = 0; index < num_interfaces; index++) {
608 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
609 interk->link_class_impl(throw_verifyerror, CHECK_false);
610 }
611
612 // If a value type is referenced by a class (either as a field type or a
613 // method argument or return type) this value type must be loaded during
614 // the linking of this class because size and properties of the value type
615 // must be known in order to be able to perform value type optimizations
616
617 // Note: circular dependencies between value types are not handled yet
618
619 // Note: one case is not handled yet: arrays of value types => FixMe
620
621 // Note: the current implementation is not optimized because the search for
622 // value types is performed on all classes. It would be more efficient to
623 // detect value types during verification and 'tag' the classes for which
624 // value type loading is required. However, this optimization won't be
625 // applicable to classes that are not verified
626
627 // First step: fields
628 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
629 ResourceMark rm(THREAD);
630 if (fs.field_descriptor().field_type() == T_VALUETYPE) {
631 Symbol* signature = fs.field_descriptor().signature();
632 // Get current loader and protection domain first.
633 oop loader = class_loader();
634 oop prot_domain = protection_domain();
635 Klass* klass = SystemDictionary::resolve_or_fail(signature,
636 Handle(THREAD, loader), Handle(THREAD, prot_domain), true,
637 THREAD);
638 if (klass == NULL) {
639 THROW_(vmSymbols::java_lang_LinkageError(), false);
640 }
641 }
642 }
643
644 // Second step: methods arguments and return types
645 // for (int i = 0; i < this_k->constants()->length(); i++) {
646 // if (this_k->constants()->tag_at(i).is_method()) {
647 // Symbol* signature = this_k->constants()->signature_ref_at(i);
648 // ResourceMark rm(THREAD);
649 // for (SignatureStream ss(signature); !ss.is_done(); ss.next()) {
650 // if (ss.type() == T_VALUETYPE) {
651 // Symbol* sig = ss.as_symbol(THREAD);
652 // // Get current loader and protection domain first.
653 // oop loader = this_k->class_loader();
654 // oop protection_domain = this_k->protection_domain();
655 //
656 // bool ok = SystemDictionary::resolve_or_fail(sig,
657 // Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
658 // THREAD);
659 // if (!ok) {
660 // THROW_(vmSymbols::java_lang_LinkageError(), false);
661 // }
662 // }
663 // }
664 // }
665 // }
666
667 // in case the class is linked in the process of linking its superclasses
668 if (is_linked()) {
669 return true;
670 }
671
672 // trace only the link time for this klass that includes
673 // the verification time
674 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
675 ClassLoader::perf_class_link_selftime(),
676 ClassLoader::perf_classes_linked(),
677 jt->get_thread_stat()->perf_recursion_counts_addr(),
678 jt->get_thread_stat()->perf_timers_addr(),
679 PerfClassTraceTime::CLASS_LINK);
680
681 // verification & rewriting
682 {
683 HandleMark hm(THREAD);
684 Handle h_init_lock(THREAD, init_lock());
685 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
686 // rewritten will have been set if loader constraint error found
687 // on an earlier link attempt
688 // don't verify or rewrite if already rewritten
689 //
690
691 if (!is_linked()) {
692 // The VCC must be linked before the DVT
693 if (get_vcc_klass() != NULL) {
694 InstanceKlass::cast(get_vcc_klass())->link_class(CHECK_false);
695 }
696
697 if (!is_rewritten()) {
698 {
699 bool verify_ok = verify_code(throw_verifyerror, THREAD);
700 if (!verify_ok) {
701 return false;
702 }
703 }
704
705 // Just in case a side-effect of verify linked this class already
706 // (which can sometimes happen since the verifier loads classes
707 // using custom class loaders, which are free to initialize things)
708 if (is_linked()) {
709 return true;
710 }
711
712 // also sets rewritten
713 rewrite_class(CHECK_false);
714 } else if (is_shared()) {
715 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
716 }
717
718 // relocate jsrs and link methods after they are all rewritten
719 link_methods(CHECK_false);
720
721 // Initialize the vtable and interface table after
722 // methods have been rewritten since rewrite may
723 // fabricate new Method*s.
724 // also does loader constraint checking
725 //
726 // initialize_vtable and initialize_itable need to be rerun for
727 // a shared class if the class is not loaded by the NULL classloader.
728 ClassLoaderData * loader_data = class_loader_data();
729 if (!(is_shared() &&
730 loader_data->is_the_null_class_loader_data())) {
731 ResourceMark rm(THREAD);
732 vtable().initialize_vtable(true, CHECK_false);
733 itable().initialize_itable(true, CHECK_false);
734 }
735 #ifdef ASSERT
736 else {
737 vtable().verify(tty, true);
738 // In case itable verification is ever added.
739 // itable().verify(tty, true);
740 }
741 #endif
742
743 set_init_state(linked);
744 if (JvmtiExport::should_post_class_prepare()) {
745 Thread *thread = THREAD;
746 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
747 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
748 }
749 }
750 }
751 return true;
752 }
753
754
755 // Rewrite the byte codes of all of the methods of a class.
756 // The rewriter must be called exactly once. Rewriting must happen after
757 // verification but before the first method of the class is executed.
758 void InstanceKlass::rewrite_class(TRAPS) {
759 assert(is_loaded(), "must be loaded");
760 if (is_rewritten()) {
761 assert(is_shared(), "rewriting an unshared class?");
762 return;
763 }
764 Rewriter::rewrite(this, CHECK);
765 set_rewritten();
766 }
767
768 // Now relocate and link method entry points after class is rewritten.
769 // This is outside is_rewritten flag. In case of an exception, it can be
770 // executed more than once.
771 void InstanceKlass::link_methods(TRAPS) {
772 int len = methods()->length();
773 for (int i = len-1; i >= 0; i--) {
774 methodHandle m(THREAD, methods()->at(i));
775
776 // Set up method entry points for compiler and interpreter .
777 m->link_method(m, CHECK);
778 }
779 }
780
781 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
782 void InstanceKlass::initialize_super_interfaces(TRAPS) {
783 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
784 for (int i = 0; i < local_interfaces()->length(); ++i) {
785 Klass* iface = local_interfaces()->at(i);
786 InstanceKlass* ik = InstanceKlass::cast(iface);
787
788 // Initialization is depth first search ie. we start with top of the inheritance tree
789 // has_nonstatic_concrete_methods drives searching superinterfaces since it
790 // means has_nonstatic_concrete_methods in its superinterface hierarchy
791 if (ik->has_nonstatic_concrete_methods()) {
792 ik->initialize_super_interfaces(CHECK);
793 }
794
795 // Only initialize() interfaces that "declare" concrete methods.
796 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
797 ik->initialize(CHECK);
798 }
799 }
800 }
801
802 void InstanceKlass::initialize_impl(TRAPS) {
803 HandleMark hm(THREAD);
804
805 // ensure outer VCC is initialized, possible some crafty code referred to VT 1st
806 if (get_vcc_klass() != NULL) {
807 get_vcc_klass()->initialize(CHECK);
808 }
809
810 // Make sure klass is linked (verified) before initialization
811 // A class could already be verified, since it has been reflected upon.
812 link_class(CHECK);
813
814 DTRACE_CLASSINIT_PROBE(required, -1);
815
816 bool wait = false;
817
818 // refer to the JVM book page 47 for description of steps
819 // Step 1
820 {
821 Handle h_init_lock(THREAD, init_lock());
822 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
823
824 Thread *self = THREAD; // it's passed the current thread
825
826 // Step 2
827 // If we were to use wait() instead of waitInterruptibly() then
828 // we might end up throwing IE from link/symbol resolution sites
829 // that aren't expected to throw. This would wreak havoc. See 6320309.
830 while(is_being_initialized() && !is_reentrant_initialization(self)) {
831 wait = true;
832 ol.waitUninterruptibly(CHECK);
833 }
834
835 // Step 3
836 if (is_being_initialized() && is_reentrant_initialization(self)) {
837 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
838 return;
839 }
840
841 // Step 4
842 if (is_initialized()) {
843 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
844 return;
845 }
846
847 // Step 5
848 if (is_in_error_state()) {
849 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
850 ResourceMark rm(THREAD);
851 const char* desc = "Could not initialize class ";
852 const char* className = external_name();
853 size_t msglen = strlen(desc) + strlen(className) + 1;
854 char* message = NEW_RESOURCE_ARRAY(char, msglen);
855 if (NULL == message) {
856 // Out of memory: can't create detailed error message
857 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
858 } else {
859 jio_snprintf(message, msglen, "%s%s", desc, className);
860 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
861 }
862 }
863
864 // Step 6
865 set_init_state(being_initialized);
866 set_init_thread(self);
867 }
868
869 // Step 7
870 // Next, if C is a class rather than an interface, initialize it's super class and super
871 // interfaces.
872 if (!is_interface()) {
873 Klass* super_klass = super();
874 if (super_klass != NULL && super_klass->should_be_initialized()) {
875 super_klass->initialize(THREAD);
876 }
877 // If C implements any interface that declares a non-static, concrete method,
878 // the initialization of C triggers initialization of its super interfaces.
879 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
880 // having a superinterface that declares, non-static, concrete methods
881 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
882 initialize_super_interfaces(THREAD);
883 }
884
885 // If any exceptions, complete abruptly, throwing the same exception as above.
886 if (HAS_PENDING_EXCEPTION) {
887 Handle e(THREAD, PENDING_EXCEPTION);
888 CLEAR_PENDING_EXCEPTION;
889 {
890 EXCEPTION_MARK;
891 // Locks object, set state, and notify all waiting threads
892 set_initialization_state_and_notify(initialization_error, THREAD);
893 CLEAR_PENDING_EXCEPTION;
894 }
895 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
896 THROW_OOP(e());
897 }
898 }
899
900
901 // Look for aot compiled methods for this klass, including class initializer.
902 AOTLoader::load_for_klass(this, THREAD);
903
904 // Step 8
905 {
906 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
907 JavaThread* jt = (JavaThread*)THREAD;
908 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
909 // Timer includes any side effects of class initialization (resolution,
910 // etc), but not recursive entry into call_class_initializer().
911 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
912 ClassLoader::perf_class_init_selftime(),
913 ClassLoader::perf_classes_inited(),
914 jt->get_thread_stat()->perf_recursion_counts_addr(),
915 jt->get_thread_stat()->perf_timers_addr(),
916 PerfClassTraceTime::CLASS_CLINIT);
917 call_class_initializer(THREAD);
918 }
919
920 // Step 9
921 if (!HAS_PENDING_EXCEPTION) {
922 set_initialization_state_and_notify(fully_initialized, CHECK);
923 {
924 debug_only(vtable().verify(tty, true);)
925 }
926 }
927 else {
928 // Step 10 and 11
929 Handle e(THREAD, PENDING_EXCEPTION);
930 CLEAR_PENDING_EXCEPTION;
931 // JVMTI has already reported the pending exception
932 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
933 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
934 {
935 EXCEPTION_MARK;
936 set_initialization_state_and_notify(initialization_error, THREAD);
937 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
938 // JVMTI has already reported the pending exception
939 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
940 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
941 }
942 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
943 if (e->is_a(SystemDictionary::Error_klass())) {
944 THROW_OOP(e());
945 } else {
946 JavaCallArguments args(e);
947 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
948 vmSymbols::throwable_void_signature(),
949 &args);
950 }
951 }
952 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
953 }
954
955
956 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
957 Handle h_init_lock(THREAD, init_lock());
958 if (h_init_lock() != NULL) {
959 ObjectLocker ol(h_init_lock, THREAD);
960 set_init_state(state);
961 fence_and_clear_init_lock();
962 ol.notify_all(CHECK);
963 } else {
964 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
965 set_init_state(state);
966 }
967 }
968
969 // The embedded _implementor field can only record one implementor.
970 // When there are more than one implementors, the _implementor field
971 // is set to the interface Klass* itself. Following are the possible
972 // values for the _implementor field:
973 // NULL - no implementor
974 // implementor Klass* - one implementor
975 // self - more than one implementor
976 //
977 // The _implementor field only exists for interfaces.
978 void InstanceKlass::add_implementor(Klass* k) {
979 assert(Compile_lock->owned_by_self(), "");
980 assert(is_interface(), "not interface");
981 // Filter out my subinterfaces.
982 // (Note: Interfaces are never on the subklass list.)
983 if (InstanceKlass::cast(k)->is_interface()) return;
984
985 // Filter out subclasses whose supers already implement me.
986 // (Note: CHA must walk subclasses of direct implementors
987 // in order to locate indirect implementors.)
988 Klass* sk = k->super();
989 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
990 // We only need to check one immediate superclass, since the
991 // implements_interface query looks at transitive_interfaces.
992 // Any supers of the super have the same (or fewer) transitive_interfaces.
993 return;
994
995 Klass* ik = implementor();
996 if (ik == NULL) {
997 set_implementor(k);
998 } else if (ik != this) {
999 // There is already an implementor. Use itself as an indicator of
1000 // more than one implementors.
1001 set_implementor(this);
1002 }
1003
1004 // The implementor also implements the transitive_interfaces
1005 for (int index = 0; index < local_interfaces()->length(); index++) {
1006 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1007 }
1008 }
1009
1010 void InstanceKlass::init_implementor() {
1011 if (is_interface()) {
1012 set_implementor(NULL);
1013 }
1014 }
1015
1016
1017 void InstanceKlass::process_interfaces(Thread *thread) {
1018 // link this class into the implementors list of every interface it implements
1019 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1020 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1021 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1022 assert(interf->is_interface(), "expected interface");
1023 interf->add_implementor(this);
1024 }
1025 }
1026
1027 bool InstanceKlass::can_be_primary_super_slow() const {
1028 if (is_interface())
1029 return false;
1030 else
1031 return Klass::can_be_primary_super_slow();
1032 }
1033
1034 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1035 // The secondaries are the implemented interfaces.
1036 Array<Klass*>* interfaces = transitive_interfaces();
1037 int num_secondaries = num_extra_slots + interfaces->length();
1038 if (num_secondaries == 0) {
1039 // Must share this for correct bootstrapping!
1040 set_secondary_supers(Universe::the_empty_klass_array());
1041 return NULL;
1042 } else if (num_extra_slots == 0) {
1043 // The secondary super list is exactly the same as the transitive interfaces.
1044 // Redefine classes has to be careful not to delete this!
1045 set_secondary_supers(interfaces);
1046 return NULL;
1047 } else {
1048 // Copy transitive interfaces to a temporary growable array to be constructed
1049 // into the secondary super list with extra slots.
1050 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1051 for (int i = 0; i < interfaces->length(); i++) {
1052 secondaries->push(interfaces->at(i));
1053 }
1054 return secondaries;
1055 }
1056 }
1057
1058 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1059 if (k->is_interface()) {
1060 return implements_interface(k);
1061 } else {
1062 return Klass::compute_is_subtype_of(k);
1063 }
1064 }
1065
1066 bool InstanceKlass::implements_interface(Klass* k) const {
1067 if (this == k) return true;
1068 assert(k->is_interface(), "should be an interface class");
1069 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1070 if (transitive_interfaces()->at(i) == k) {
1071 return true;
1072 }
1073 }
1074 return false;
1075 }
1076
1077 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1078 // Verify direct super interface
1079 if (this == k) return true;
1080 assert(k->is_interface(), "should be an interface class");
1081 for (int i = 0; i < local_interfaces()->length(); i++) {
1082 if (local_interfaces()->at(i) == k) {
1083 return true;
1084 }
1085 }
1086 return false;
1087 }
1088
1089 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1090 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1091 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1092 report_java_out_of_memory("Requested array size exceeds VM limit");
1093 JvmtiExport::post_array_size_exhausted();
1094 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1095 }
1096 int size = objArrayOopDesc::object_size(length);
1097 Klass* ak = array_klass(n, CHECK_NULL);
1098 objArrayOop o =
1099 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1100 return o;
1101 }
1102
1103 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1104 if (TraceFinalizerRegistration) {
1105 tty->print("Registered ");
1106 i->print_value_on(tty);
1107 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1108 }
1109 instanceHandle h_i(THREAD, i);
1110 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1111 JavaValue result(T_VOID);
1112 JavaCallArguments args(h_i);
1113 methodHandle mh (THREAD, Universe::finalizer_register_method());
1114 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1115 return h_i();
1116 }
1117
1118 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1119 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1120 int size = size_helper(); // Query before forming handle.
1121
1122 instanceOop i;
1123
1124 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1125 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1126 i = register_finalizer(i, CHECK_NULL);
1127 }
1128 return i;
1129 }
1130
1131 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1132 if (is_interface() || is_abstract()) {
1133 ResourceMark rm(THREAD);
1134 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1135 : vmSymbols::java_lang_InstantiationException(), external_name());
1136 }
1137 if (this == SystemDictionary::Class_klass()) {
1138 ResourceMark rm(THREAD);
1139 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1140 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1141 }
1142 }
1143
1144 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1145 // Need load-acquire for lock-free read
1146 if (array_klasses_acquire() == NULL) {
1147 if (or_null) return NULL;
1148
1149 ResourceMark rm;
1150 JavaThread *jt = (JavaThread *)THREAD;
1151 {
1152 // Atomic creation of array_klasses
1153 MutexLocker mc(Compile_lock, THREAD); // for vtables
1154 MutexLocker ma(MultiArray_lock, THREAD);
1155
1156 // Check if update has already taken place
1157 if (array_klasses() == NULL) {
1158 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1159 // use 'release' to pair with lock-free load
1160 release_set_array_klasses(k);
1161 }
1162 }
1163 }
1164 // _this will always be set at this point
1165 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1166 if (or_null) {
1167 return oak->array_klass_or_null(n);
1168 }
1169 return oak->array_klass(n, THREAD);
1170 }
1171
1172 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1173 return array_klass_impl(or_null, 1, THREAD);
1174 }
1175
1176 static int call_class_initializer_counter = 0; // for debugging
1177
1178 Method* InstanceKlass::class_initializer() const {
1179 Method* clinit = find_method(
1180 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1181 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1182 return clinit;
1183 }
1184 return NULL;
1185 }
1186
1187 void InstanceKlass::call_class_initializer(TRAPS) {
1188 if (ReplayCompiles &&
1189 (ReplaySuppressInitializers == 1 ||
1190 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1191 // Hide the existence of the initializer for the purpose of replaying the compile
1192 return;
1193 }
1194
1195 methodHandle h_method(THREAD, class_initializer());
1196 assert(!is_initialized(), "we cannot initialize twice");
1197 LogTarget(Info, class, init) lt;
1198 if (lt.is_enabled()) {
1199 ResourceMark rm;
1200 LogStream ls(lt);
1201 ls.print("%d Initializing ", call_class_initializer_counter++);
1202 name()->print_value_on(&ls);
1203 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1204 }
1205 if (h_method() != NULL) {
1206 JavaCallArguments args; // No arguments
1207 JavaValue result(T_VOID);
1208 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1209 }
1210 }
1211
1212
1213 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1214 InterpreterOopMap* entry_for) {
1215 // Lazily create the _oop_map_cache at first request
1216 // Lock-free access requires load_acquire.
1217 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1218 if (oop_map_cache == NULL) {
1219 MutexLockerEx x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1220 // Check if _oop_map_cache was allocated while we were waiting for this lock
1221 if ((oop_map_cache = _oop_map_cache) == NULL) {
1222 oop_map_cache = new OopMapCache();
1223 // Ensure _oop_map_cache is stable, since it is examined without a lock
1224 OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1225 }
1226 }
1227 // _oop_map_cache is constant after init; lookup below does its own locking.
1228 oop_map_cache->lookup(method, bci, entry_for);
1229 }
1230
1231
1232 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1233 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1234 Symbol* f_name = fs.name();
1235 Symbol* f_sig = fs.signature();
1236 if (f_name == name && f_sig == sig) {
1237 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1238 return true;
1239 }
1240 }
1241 return false;
1242 }
1243
1244
1245 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1246 const int n = local_interfaces()->length();
1247 for (int i = 0; i < n; i++) {
1248 Klass* intf1 = local_interfaces()->at(i);
1249 assert(intf1->is_interface(), "just checking type");
1250 // search for field in current interface
1251 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1252 assert(fd->is_static(), "interface field must be static");
1253 return intf1;
1254 }
1255 // search for field in direct superinterfaces
1256 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1257 if (intf2 != NULL) return intf2;
1258 }
1259 // otherwise field lookup fails
1260 return NULL;
1261 }
1262
1263
1264 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1265 // search order according to newest JVM spec (5.4.3.2, p.167).
1266 // 1) search for field in current klass
1267 if (find_local_field(name, sig, fd)) {
1268 return const_cast<InstanceKlass*>(this);
1269 }
1270 // 2) search for field recursively in direct superinterfaces
1271 { Klass* intf = find_interface_field(name, sig, fd);
1272 if (intf != NULL) return intf;
1273 }
1274 // 3) apply field lookup recursively if superclass exists
1275 { Klass* supr = super();
1276 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1277 }
1278 // 4) otherwise field lookup fails
1279 return NULL;
1280 }
1281
1282
1283 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1284 // search order according to newest JVM spec (5.4.3.2, p.167).
1285 // 1) search for field in current klass
1286 if (find_local_field(name, sig, fd)) {
1287 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1288 }
1289 // 2) search for field recursively in direct superinterfaces
1290 if (is_static) {
1291 Klass* intf = find_interface_field(name, sig, fd);
1292 if (intf != NULL) return intf;
1293 }
1294 // 3) apply field lookup recursively if superclass exists
1295 { Klass* supr = super();
1296 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1297 }
1298 // 4) otherwise field lookup fails
1299 return NULL;
1300 }
1301
1302
1303 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1304 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1305 if (fs.offset() == offset) {
1306 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1307 if (fd->is_static() == is_static) return true;
1308 }
1309 }
1310 return false;
1311 }
1312
1313
1314 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1315 Klass* klass = const_cast<InstanceKlass*>(this);
1316 while (klass != NULL) {
1317 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1318 return true;
1319 }
1320 klass = klass->super();
1321 }
1322 return false;
1323 }
1324
1325
1326 void InstanceKlass::methods_do(void f(Method* method)) {
1327 // Methods aren't stable until they are loaded. This can be read outside
1328 // a lock through the ClassLoaderData for profiling
1329 if (!is_loaded()) {
1330 return;
1331 }
1332
1333 int len = methods()->length();
1334 for (int index = 0; index < len; index++) {
1335 Method* m = methods()->at(index);
1336 assert(m->is_method(), "must be method");
1337 f(m);
1338 }
1339 }
1340
1341
1342 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1343 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1344 if (fs.access_flags().is_static()) {
1345 fieldDescriptor& fd = fs.field_descriptor();
1346 cl->do_field(&fd);
1347 }
1348 }
1349 }
1350
1351
1352 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1353 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1354 if (fs.access_flags().is_static()) {
1355 fieldDescriptor& fd = fs.field_descriptor();
1356 f(&fd, mirror, CHECK);
1357 }
1358 }
1359 }
1360
1361
1362 static int compare_fields_by_offset(int* a, int* b) {
1363 return a[0] - b[0];
1364 }
1365
1366 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1367 InstanceKlass* super = superklass();
1368 if (super != NULL) {
1369 super->do_nonstatic_fields(cl);
1370 }
1371 fieldDescriptor fd;
1372 int length = java_fields_count();
1373 // In DebugInfo nonstatic fields are sorted by offset.
1374 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1375 int j = 0;
1376 for (int i = 0; i < length; i += 1) {
1377 fd.reinitialize(this, i);
1378 if (!fd.is_static()) {
1379 fields_sorted[j + 0] = fd.offset();
1380 fields_sorted[j + 1] = i;
1381 j += 2;
1382 }
1383 }
1384 if (j > 0) {
1385 length = j;
1386 // _sort_Fn is defined in growableArray.hpp.
1387 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1388 for (int i = 0; i < length; i += 2) {
1389 fd.reinitialize(this, fields_sorted[i + 1]);
1390 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1391 cl->do_field(&fd);
1392 }
1393 }
1394 FREE_C_HEAP_ARRAY(int, fields_sorted);
1395 }
1396
1397
1398 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1399 if (array_klasses() != NULL)
1400 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1401 }
1402
1403 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1404 if (array_klasses() != NULL)
1405 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1406 }
1407
1408 #ifdef ASSERT
1409 static int linear_search(const Array<Method*>* methods,
1410 const Symbol* name,
1411 const Symbol* signature) {
1412 const int len = methods->length();
1413 for (int index = 0; index < len; index++) {
1414 const Method* const m = methods->at(index);
1415 assert(m->is_method(), "must be method");
1416 if (m->signature() == signature && m->name() == name) {
1417 return index;
1418 }
1419 }
1420 return -1;
1421 }
1422 #endif
1423
1424 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1425 int len = methods->length();
1426 // methods are sorted, so do binary search
1427 int l = 0;
1428 int h = len - 1;
1429 while (l <= h) {
1430 int mid = (l + h) >> 1;
1431 Method* m = methods->at(mid);
1432 assert(m->is_method(), "must be method");
1433 int res = m->name()->fast_compare(name);
1434 if (res == 0) {
1435 return mid;
1436 } else if (res < 0) {
1437 l = mid + 1;
1438 } else {
1439 h = mid - 1;
1440 }
1441 }
1442 return -1;
1443 }
1444
1445 // find_method looks up the name/signature in the local methods array
1446 Method* InstanceKlass::find_method(const Symbol* name,
1447 const Symbol* signature) const {
1448 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1449 }
1450
1451 Method* InstanceKlass::find_method_impl(const Symbol* name,
1452 const Symbol* signature,
1453 OverpassLookupMode overpass_mode,
1454 StaticLookupMode static_mode,
1455 PrivateLookupMode private_mode) const {
1456 return InstanceKlass::find_method_impl(methods(),
1457 name,
1458 signature,
1459 overpass_mode,
1460 static_mode,
1461 private_mode);
1462 }
1463
1464 // find_instance_method looks up the name/signature in the local methods array
1465 // and skips over static methods
1466 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1467 const Symbol* name,
1468 const Symbol* signature) {
1469 Method* const meth = InstanceKlass::find_method_impl(methods,
1470 name,
1471 signature,
1472 find_overpass,
1473 skip_static,
1474 find_private);
1475 assert(((meth == NULL) || !meth->is_static()),
1476 "find_instance_method should have skipped statics");
1477 return meth;
1478 }
1479
1480 // find_instance_method looks up the name/signature in the local methods array
1481 // and skips over static methods
1482 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1483 return InstanceKlass::find_instance_method(methods(), name, signature);
1484 }
1485
1486 // Find looks up the name/signature in the local methods array
1487 // and filters on the overpass, static and private flags
1488 // This returns the first one found
1489 // note that the local methods array can have up to one overpass, one static
1490 // and one instance (private or not) with the same name/signature
1491 Method* InstanceKlass::find_local_method(const Symbol* name,
1492 const Symbol* signature,
1493 OverpassLookupMode overpass_mode,
1494 StaticLookupMode static_mode,
1495 PrivateLookupMode private_mode) const {
1496 return InstanceKlass::find_method_impl(methods(),
1497 name,
1498 signature,
1499 overpass_mode,
1500 static_mode,
1501 private_mode);
1502 }
1503
1504 // Find looks up the name/signature in the local methods array
1505 // and filters on the overpass, static and private flags
1506 // This returns the first one found
1507 // note that the local methods array can have up to one overpass, one static
1508 // and one instance (private or not) with the same name/signature
1509 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1510 const Symbol* name,
1511 const Symbol* signature,
1512 OverpassLookupMode overpass_mode,
1513 StaticLookupMode static_mode,
1514 PrivateLookupMode private_mode) {
1515 return InstanceKlass::find_method_impl(methods,
1516 name,
1517 signature,
1518 overpass_mode,
1519 static_mode,
1520 private_mode);
1521 }
1522
1523 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1524 const Symbol* name,
1525 const Symbol* signature) {
1526 return InstanceKlass::find_method_impl(methods,
1527 name,
1528 signature,
1529 find_overpass,
1530 find_static,
1531 find_private);
1532 }
1533
1534 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1535 const Symbol* name,
1536 const Symbol* signature,
1537 OverpassLookupMode overpass_mode,
1538 StaticLookupMode static_mode,
1539 PrivateLookupMode private_mode) {
1540 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1541 return hit >= 0 ? methods->at(hit): NULL;
1542 }
1543
1544 // true if method matches signature and conforms to skipping_X conditions.
1545 static bool method_matches(const Method* m,
1546 const Symbol* signature,
1547 bool skipping_overpass,
1548 bool skipping_static,
1549 bool skipping_private) {
1550 return ((m->signature() == signature) &&
1551 (!skipping_overpass || !m->is_overpass()) &&
1552 (!skipping_static || !m->is_static()) &&
1553 (!skipping_private || !m->is_private()));
1554 }
1555
1556 // Used directly for default_methods to find the index into the
1557 // default_vtable_indices, and indirectly by find_method
1558 // find_method_index looks in the local methods array to return the index
1559 // of the matching name/signature. If, overpass methods are being ignored,
1560 // the search continues to find a potential non-overpass match. This capability
1561 // is important during method resolution to prefer a static method, for example,
1562 // over an overpass method.
1563 // There is the possibility in any _method's array to have the same name/signature
1564 // for a static method, an overpass method and a local instance method
1565 // To correctly catch a given method, the search criteria may need
1566 // to explicitly skip the other two. For local instance methods, it
1567 // is often necessary to skip private methods
1568 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1569 const Symbol* name,
1570 const Symbol* signature,
1571 OverpassLookupMode overpass_mode,
1572 StaticLookupMode static_mode,
1573 PrivateLookupMode private_mode) {
1574 const bool skipping_overpass = (overpass_mode == skip_overpass);
1575 const bool skipping_static = (static_mode == skip_static);
1576 const bool skipping_private = (private_mode == skip_private);
1577 const int hit = binary_search(methods, name);
1578 if (hit != -1) {
1579 const Method* const m = methods->at(hit);
1580
1581 // Do linear search to find matching signature. First, quick check
1582 // for common case, ignoring overpasses if requested.
1583 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1584 return hit;
1585 }
1586
1587 // search downwards through overloaded methods
1588 int i;
1589 for (i = hit - 1; i >= 0; --i) {
1590 const Method* const m = methods->at(i);
1591 assert(m->is_method(), "must be method");
1592 if (m->name() != name) {
1593 break;
1594 }
1595 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1596 return i;
1597 }
1598 }
1599 // search upwards
1600 for (i = hit + 1; i < methods->length(); ++i) {
1601 const Method* const m = methods->at(i);
1602 assert(m->is_method(), "must be method");
1603 if (m->name() != name) {
1604 break;
1605 }
1606 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1607 return i;
1608 }
1609 }
1610 // not found
1611 #ifdef ASSERT
1612 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1613 linear_search(methods, name, signature);
1614 assert(-1 == index, "binary search should have found entry %d", index);
1615 #endif
1616 }
1617 return -1;
1618 }
1619
1620 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1621 return find_method_by_name(methods(), name, end);
1622 }
1623
1624 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1625 const Symbol* name,
1626 int* end_ptr) {
1627 assert(end_ptr != NULL, "just checking");
1628 int start = binary_search(methods, name);
1629 int end = start + 1;
1630 if (start != -1) {
1631 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1632 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1633 *end_ptr = end;
1634 return start;
1635 }
1636 return -1;
1637 }
1638
1639 // uncached_lookup_method searches both the local class methods array and all
1640 // superclasses methods arrays, skipping any overpass methods in superclasses.
1641 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1642 const Symbol* signature,
1643 OverpassLookupMode overpass_mode) const {
1644 OverpassLookupMode overpass_local_mode = overpass_mode;
1645 const Klass* klass = this;
1646 while (klass != NULL) {
1647 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1648 signature,
1649 overpass_local_mode,
1650 find_static,
1651 find_private);
1652 if (method != NULL) {
1653 return method;
1654 }
1655 klass = klass->super();
1656 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1657 }
1658 return NULL;
1659 }
1660
1661 #ifdef ASSERT
1662 // search through class hierarchy and return true if this class or
1663 // one of the superclasses was redefined
1664 bool InstanceKlass::has_redefined_this_or_super() const {
1665 const Klass* klass = this;
1666 while (klass != NULL) {
1667 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1668 return true;
1669 }
1670 klass = klass->super();
1671 }
1672 return false;
1673 }
1674 #endif
1675
1676 // lookup a method in the default methods list then in all transitive interfaces
1677 // Do NOT return private or static methods
1678 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1679 Symbol* signature) const {
1680 Method* m = NULL;
1681 if (default_methods() != NULL) {
1682 m = find_method(default_methods(), name, signature);
1683 }
1684 // Look up interfaces
1685 if (m == NULL) {
1686 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1687 }
1688 return m;
1689 }
1690
1691 // lookup a method in all the interfaces that this class implements
1692 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1693 // They should only be found in the initial InterfaceMethodRef
1694 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1695 Symbol* signature,
1696 DefaultsLookupMode defaults_mode) const {
1697 Array<Klass*>* all_ifs = transitive_interfaces();
1698 int num_ifs = all_ifs->length();
1699 InstanceKlass *ik = NULL;
1700 for (int i = 0; i < num_ifs; i++) {
1701 ik = InstanceKlass::cast(all_ifs->at(i));
1702 Method* m = ik->lookup_method(name, signature);
1703 if (m != NULL && m->is_public() && !m->is_static() &&
1704 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1705 return m;
1706 }
1707 }
1708 return NULL;
1709 }
1710
1711 /* jni_id_for_impl for jfieldIds only */
1712 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1713 MutexLocker ml(JfieldIdCreation_lock);
1714 // Retry lookup after we got the lock
1715 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1716 if (probe == NULL) {
1717 // Slow case, allocate new static field identifier
1718 probe = new JNIid(this, offset, jni_ids());
1719 set_jni_ids(probe);
1720 }
1721 return probe;
1722 }
1723
1724
1725 /* jni_id_for for jfieldIds only */
1726 JNIid* InstanceKlass::jni_id_for(int offset) {
1727 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1728 if (probe == NULL) {
1729 probe = jni_id_for_impl(offset);
1730 }
1731 return probe;
1732 }
1733
1734 u2 InstanceKlass::enclosing_method_data(int offset) const {
1735 const Array<jushort>* const inner_class_list = inner_classes();
1736 if (inner_class_list == NULL) {
1737 return 0;
1738 }
1739 const int length = inner_class_list->length();
1740 if (length % inner_class_next_offset == 0) {
1741 return 0;
1742 }
1743 const int index = length - enclosing_method_attribute_size;
1744 assert(offset < enclosing_method_attribute_size, "invalid offset");
1745 return inner_class_list->at(index + offset);
1746 }
1747
1748 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1749 u2 method_index) {
1750 Array<jushort>* inner_class_list = inner_classes();
1751 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1752 int length = inner_class_list->length();
1753 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1754 int index = length - enclosing_method_attribute_size;
1755 inner_class_list->at_put(
1756 index + enclosing_method_class_index_offset, class_index);
1757 inner_class_list->at_put(
1758 index + enclosing_method_method_index_offset, method_index);
1759 }
1760 }
1761
1762 // Lookup or create a jmethodID.
1763 // This code is called by the VMThread and JavaThreads so the
1764 // locking has to be done very carefully to avoid deadlocks
1765 // and/or other cache consistency problems.
1766 //
1767 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1768 size_t idnum = (size_t)method_h->method_idnum();
1769 jmethodID* jmeths = methods_jmethod_ids_acquire();
1770 size_t length = 0;
1771 jmethodID id = NULL;
1772
1773 // We use a double-check locking idiom here because this cache is
1774 // performance sensitive. In the normal system, this cache only
1775 // transitions from NULL to non-NULL which is safe because we use
1776 // release_set_methods_jmethod_ids() to advertise the new cache.
1777 // A partially constructed cache should never be seen by a racing
1778 // thread. We also use release_store() to save a new jmethodID
1779 // in the cache so a partially constructed jmethodID should never be
1780 // seen either. Cache reads of existing jmethodIDs proceed without a
1781 // lock, but cache writes of a new jmethodID requires uniqueness and
1782 // creation of the cache itself requires no leaks so a lock is
1783 // generally acquired in those two cases.
1784 //
1785 // If the RedefineClasses() API has been used, then this cache can
1786 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1787 // Cache creation requires no leaks and we require safety between all
1788 // cache accesses and freeing of the old cache so a lock is generally
1789 // acquired when the RedefineClasses() API has been used.
1790
1791 if (jmeths != NULL) {
1792 // the cache already exists
1793 if (!idnum_can_increment()) {
1794 // the cache can't grow so we can just get the current values
1795 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1796 } else {
1797 // cache can grow so we have to be more careful
1798 if (Threads::number_of_threads() == 0 ||
1799 SafepointSynchronize::is_at_safepoint()) {
1800 // we're single threaded or at a safepoint - no locking needed
1801 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1802 } else {
1803 MutexLocker ml(JmethodIdCreation_lock);
1804 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1805 }
1806 }
1807 }
1808 // implied else:
1809 // we need to allocate a cache so default length and id values are good
1810
1811 if (jmeths == NULL || // no cache yet
1812 length <= idnum || // cache is too short
1813 id == NULL) { // cache doesn't contain entry
1814
1815 // This function can be called by the VMThread so we have to do all
1816 // things that might block on a safepoint before grabbing the lock.
1817 // Otherwise, we can deadlock with the VMThread or have a cache
1818 // consistency issue. These vars keep track of what we might have
1819 // to free after the lock is dropped.
1820 jmethodID to_dealloc_id = NULL;
1821 jmethodID* to_dealloc_jmeths = NULL;
1822
1823 // may not allocate new_jmeths or use it if we allocate it
1824 jmethodID* new_jmeths = NULL;
1825 if (length <= idnum) {
1826 // allocate a new cache that might be used
1827 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1828 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1829 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1830 // cache size is stored in element[0], other elements offset by one
1831 new_jmeths[0] = (jmethodID)size;
1832 }
1833
1834 // allocate a new jmethodID that might be used
1835 jmethodID new_id = NULL;
1836 if (method_h->is_old() && !method_h->is_obsolete()) {
1837 // The method passed in is old (but not obsolete), we need to use the current version
1838 Method* current_method = method_with_idnum((int)idnum);
1839 assert(current_method != NULL, "old and but not obsolete, so should exist");
1840 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1841 } else {
1842 // It is the current version of the method or an obsolete method,
1843 // use the version passed in
1844 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1845 }
1846
1847 if (Threads::number_of_threads() == 0 ||
1848 SafepointSynchronize::is_at_safepoint()) {
1849 // we're single threaded or at a safepoint - no locking needed
1850 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1851 &to_dealloc_id, &to_dealloc_jmeths);
1852 } else {
1853 MutexLocker ml(JmethodIdCreation_lock);
1854 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1855 &to_dealloc_id, &to_dealloc_jmeths);
1856 }
1857
1858 // The lock has been dropped so we can free resources.
1859 // Free up either the old cache or the new cache if we allocated one.
1860 if (to_dealloc_jmeths != NULL) {
1861 FreeHeap(to_dealloc_jmeths);
1862 }
1863 // free up the new ID since it wasn't needed
1864 if (to_dealloc_id != NULL) {
1865 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1866 }
1867 }
1868 return id;
1869 }
1870
1871 // Figure out how many jmethodIDs haven't been allocated, and make
1872 // sure space for them is pre-allocated. This makes getting all
1873 // method ids much, much faster with classes with more than 8
1874 // methods, and has a *substantial* effect on performance with jvmti
1875 // code that loads all jmethodIDs for all classes.
1876 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1877 int new_jmeths = 0;
1878 int length = methods()->length();
1879 for (int index = start_offset; index < length; index++) {
1880 Method* m = methods()->at(index);
1881 jmethodID id = m->find_jmethod_id_or_null();
1882 if (id == NULL) {
1883 new_jmeths++;
1884 }
1885 }
1886 if (new_jmeths != 0) {
1887 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1888 }
1889 }
1890
1891 // Common code to fetch the jmethodID from the cache or update the
1892 // cache with the new jmethodID. This function should never do anything
1893 // that causes the caller to go to a safepoint or we can deadlock with
1894 // the VMThread or have cache consistency issues.
1895 //
1896 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1897 size_t idnum, jmethodID new_id,
1898 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1899 jmethodID** to_dealloc_jmeths_p) {
1900 assert(new_id != NULL, "sanity check");
1901 assert(to_dealloc_id_p != NULL, "sanity check");
1902 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1903 assert(Threads::number_of_threads() == 0 ||
1904 SafepointSynchronize::is_at_safepoint() ||
1905 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1906
1907 // reacquire the cache - we are locked, single threaded or at a safepoint
1908 jmethodID* jmeths = methods_jmethod_ids_acquire();
1909 jmethodID id = NULL;
1910 size_t length = 0;
1911
1912 if (jmeths == NULL || // no cache yet
1913 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1914 if (jmeths != NULL) {
1915 // copy any existing entries from the old cache
1916 for (size_t index = 0; index < length; index++) {
1917 new_jmeths[index+1] = jmeths[index+1];
1918 }
1919 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1920 }
1921 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1922 } else {
1923 // fetch jmethodID (if any) from the existing cache
1924 id = jmeths[idnum+1];
1925 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1926 }
1927 if (id == NULL) {
1928 // No matching jmethodID in the existing cache or we have a new
1929 // cache or we just grew the cache. This cache write is done here
1930 // by the first thread to win the foot race because a jmethodID
1931 // needs to be unique once it is generally available.
1932 id = new_id;
1933
1934 // The jmethodID cache can be read while unlocked so we have to
1935 // make sure the new jmethodID is complete before installing it
1936 // in the cache.
1937 OrderAccess::release_store(&jmeths[idnum+1], id);
1938 } else {
1939 *to_dealloc_id_p = new_id; // save new id for later delete
1940 }
1941 return id;
1942 }
1943
1944
1945 // Common code to get the jmethodID cache length and the jmethodID
1946 // value at index idnum if there is one.
1947 //
1948 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1949 size_t idnum, size_t *length_p, jmethodID* id_p) {
1950 assert(cache != NULL, "sanity check");
1951 assert(length_p != NULL, "sanity check");
1952 assert(id_p != NULL, "sanity check");
1953
1954 // cache size is stored in element[0], other elements offset by one
1955 *length_p = (size_t)cache[0];
1956 if (*length_p <= idnum) { // cache is too short
1957 *id_p = NULL;
1958 } else {
1959 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1960 }
1961 }
1962
1963
1964 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1965 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1966 size_t idnum = (size_t)method->method_idnum();
1967 jmethodID* jmeths = methods_jmethod_ids_acquire();
1968 size_t length; // length assigned as debugging crumb
1969 jmethodID id = NULL;
1970 if (jmeths != NULL && // If there is a cache
1971 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1972 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1973 }
1974 return id;
1975 }
1976
1977 inline DependencyContext InstanceKlass::dependencies() {
1978 DependencyContext dep_context(&_dep_context);
1979 return dep_context;
1980 }
1981
1982 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1983 return dependencies().mark_dependent_nmethods(changes);
1984 }
1985
1986 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1987 dependencies().add_dependent_nmethod(nm);
1988 }
1989
1990 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1991 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1992 }
1993
1994 #ifndef PRODUCT
1995 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1996 dependencies().print_dependent_nmethods(verbose);
1997 }
1998
1999 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2000 return dependencies().is_dependent_nmethod(nm);
2001 }
2002 #endif //PRODUCT
2003
2004 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2005 clean_implementors_list(is_alive);
2006 clean_method_data(is_alive);
2007
2008 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2009 DependencyContext dep_context(&_dep_context);
2010 dep_context.expunge_stale_entries();
2011 }
2012
2013 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2014 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2015 if (is_interface()) {
2016 if (ClassUnloading) {
2017 Klass* impl = implementor();
2018 if (impl != NULL) {
2019 if (!impl->is_loader_alive(is_alive)) {
2020 // remove this guy
2021 Klass** klass = adr_implementor();
2022 assert(klass != NULL, "null klass");
2023 if (klass != NULL) {
2024 *klass = NULL;
2025 }
2026 }
2027 }
2028 }
2029 }
2030 }
2031
2032 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2033 for (int m = 0; m < methods()->length(); m++) {
2034 MethodData* mdo = methods()->at(m)->method_data();
2035 if (mdo != NULL) {
2036 mdo->clean_method_data(is_alive);
2037 }
2038 }
2039 }
2040
2041 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2042 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2043 ResourceMark rm;
2044 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2045 return false;
2046 }
2047
2048 Array<Klass*>* local_interfaces = this->local_interfaces();
2049 if (local_interfaces != NULL) {
2050 int length = local_interfaces->length();
2051 for (int i = 0; i < length; i++) {
2052 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2053 if (!intf->has_passed_fingerprint_check()) {
2054 ResourceMark rm;
2055 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2056 return false;
2057 }
2058 }
2059 }
2060
2061 return true;
2062 }
2063
2064 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) {
2065 #if INCLUDE_AOT
2066 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2067 if (CalculateClassFingerprint) {
2068 // (1) We are running AOT to generate a shared library.
2069 return true;
2070 }
2071 if (DumpSharedSpaces) {
2072 // (2) We are running -Xshare:dump to create a shared archive
2073 return true;
2074 }
2075 if (UseAOT && is_anonymous) {
2076 // (3) We are using AOT code from a shared library and see an anonymous class
2077 return true;
2078 }
2079 #endif
2080
2081 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2082 // but do not store the 64-bit fingerprint to save space.
2083 return false;
2084 }
2085
2086 bool InstanceKlass::has_stored_fingerprint() const {
2087 #if INCLUDE_AOT
2088 return should_store_fingerprint() || is_shared();
2089 #else
2090 return false;
2091 #endif
2092 }
2093
2094 uint64_t InstanceKlass::get_stored_fingerprint() const {
2095 address adr = adr_fingerprint();
2096 if (adr != NULL) {
2097 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2098 }
2099 return 0;
2100 }
2101
2102 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2103 address adr = adr_fingerprint();
2104 if (adr != NULL) {
2105 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2106
2107 ResourceMark rm;
2108 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2109 }
2110 }
2111
2112 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2113 Klass::metaspace_pointers_do(it);
2114
2115 if (log_is_enabled(Trace, cds)) {
2116 ResourceMark rm;
2117 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2118 }
2119
2120 it->push(&_annotations);
2121 it->push((Klass**)&_array_klasses);
2122 it->push(&_constants);
2123 it->push(&_inner_classes);
2124 it->push(&_array_name);
2125 #if INCLUDE_JVMTI
2126 it->push(&_previous_versions);
2127 #endif
2128 it->push(&_methods);
2129 it->push(&_default_methods);
2130 it->push(&_local_interfaces);
2131 it->push(&_transitive_interfaces);
2132 it->push(&_method_ordering);
2133 it->push(&_default_vtable_indices);
2134 it->push(&_fields);
2135
2136 if (itable_length() > 0) {
2137 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2138 int method_table_offset_in_words = ioe->offset()/wordSize;
2139 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2140 / itableOffsetEntry::size();
2141
2142 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2143 if (ioe->interface_klass() != NULL) {
2144 it->push(ioe->interface_klass_addr());
2145 itableMethodEntry* ime = ioe->first_method_entry(this);
2146 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2147 for (int index = 0; index < n; index ++) {
2148 it->push(ime[index].method_addr());
2149 }
2150 }
2151 }
2152 }
2153 }
2154
2155 void InstanceKlass::remove_unshareable_info() {
2156 Klass::remove_unshareable_info();
2157
2158 if (is_in_error_state()) {
2159 // Classes are attempted to link during dumping and may fail,
2160 // but these classes are still in the dictionary and class list in CLD.
2161 // Check in_error state first because in_error is > linked state, so
2162 // is_linked() is true.
2163 // If there's a linking error, there is nothing else to remove.
2164 return;
2165 }
2166
2167 // Unlink the class
2168 if (is_linked()) {
2169 unlink_class();
2170 }
2171 init_implementor();
2172
2173 constants()->remove_unshareable_info();
2174
2175 for (int i = 0; i < methods()->length(); i++) {
2176 Method* m = methods()->at(i);
2177 m->remove_unshareable_info();
2178 }
2179
2180 // do array classes also.
2181 if (array_klasses() != NULL) {
2182 array_klasses()->remove_unshareable_info();
2183 }
2184
2185 // These are not allocated from metaspace, but they should should all be empty
2186 // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2187 guarantee(_source_debug_extension == NULL, "must be");
2188 guarantee(_dep_context == DependencyContext::EMPTY, "must be");
2189 guarantee(_osr_nmethods_head == NULL, "must be");
2190
2191 #if INCLUDE_JVMTI
2192 guarantee(_breakpoints == NULL, "must be");
2193 guarantee(_previous_versions == NULL, "must be");
2194 #endif
2195
2196 _init_thread = NULL;
2197 _methods_jmethod_ids = NULL;
2198 _jni_ids = NULL;
2199 _oop_map_cache = NULL;
2200 }
2201
2202 void InstanceKlass::remove_java_mirror() {
2203 Klass::remove_java_mirror();
2204
2205 // do array classes also.
2206 if (array_klasses() != NULL) {
2207 array_klasses()->remove_java_mirror();
2208 }
2209 }
2210
2211 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2212 set_package(loader_data, CHECK);
2213 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2214
2215 Array<Method*>* methods = this->methods();
2216 int num_methods = methods->length();
2217 for (int index2 = 0; index2 < num_methods; ++index2) {
2218 methodHandle m(THREAD, methods->at(index2));
2219 m->restore_unshareable_info(CHECK);
2220 }
2221 if (JvmtiExport::has_redefined_a_class()) {
2222 // Reinitialize vtable because RedefineClasses may have changed some
2223 // entries in this vtable for super classes so the CDS vtable might
2224 // point to old or obsolete entries. RedefineClasses doesn't fix up
2225 // vtables in the shared system dictionary, only the main one.
2226 // It also redefines the itable too so fix that too.
2227 ResourceMark rm(THREAD);
2228 vtable().initialize_vtable(false, CHECK);
2229 itable().initialize_itable(false, CHECK);
2230 }
2231
2232 // restore constant pool resolved references
2233 constants()->restore_unshareable_info(CHECK);
2234
2235 if (array_klasses() != NULL) {
2236 // Array classes have null protection domain.
2237 // --> see ArrayKlass::complete_create_array_klass()
2238 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2239 }
2240 }
2241
2242 // returns true IFF is_in_error_state() has been changed as a result of this call.
2243 bool InstanceKlass::check_sharing_error_state() {
2244 assert(DumpSharedSpaces, "should only be called during dumping");
2245 bool old_state = is_in_error_state();
2246
2247 if (!is_in_error_state()) {
2248 bool bad = false;
2249 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2250 if (sup->is_in_error_state()) {
2251 bad = true;
2252 break;
2253 }
2254 }
2255 if (!bad) {
2256 Array<Klass*>* interfaces = transitive_interfaces();
2257 for (int i = 0; i < interfaces->length(); i++) {
2258 Klass* iface = interfaces->at(i);
2259 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2260 bad = true;
2261 break;
2262 }
2263 }
2264 }
2265
2266 if (bad) {
2267 set_in_error_state();
2268 }
2269 }
2270
2271 return (old_state != is_in_error_state());
2272 }
2273
2274 #if INCLUDE_JVMTI
2275 static void clear_all_breakpoints(Method* m) {
2276 m->clear_all_breakpoints();
2277 }
2278 #endif
2279
2280 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2281 // notify the debugger
2282 if (JvmtiExport::should_post_class_unload()) {
2283 JvmtiExport::post_class_unload(ik);
2284 }
2285
2286 // notify ClassLoadingService of class unload
2287 ClassLoadingService::notify_class_unloaded(ik);
2288 }
2289
2290 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2291 // Clean up C heap
2292 ik->release_C_heap_structures();
2293 ik->constants()->release_C_heap_structures();
2294 }
2295
2296 void InstanceKlass::release_C_heap_structures() {
2297 // Can't release the constant pool here because the constant pool can be
2298 // deallocated separately from the InstanceKlass for default methods and
2299 // redefine classes.
2300
2301 // Deallocate oop map cache
2302 if (_oop_map_cache != NULL) {
2303 delete _oop_map_cache;
2304 _oop_map_cache = NULL;
2305 }
2306
2307 // Deallocate JNI identifiers for jfieldIDs
2308 JNIid::deallocate(jni_ids());
2309 set_jni_ids(NULL);
2310
2311 jmethodID* jmeths = methods_jmethod_ids_acquire();
2312 if (jmeths != (jmethodID*)NULL) {
2313 release_set_methods_jmethod_ids(NULL);
2314 FreeHeap(jmeths);
2315 }
2316
2317 // Release dependencies.
2318 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2319 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2320 // context can contain live dependencies, since there's a race between nmethod &
2321 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2322 // dependencies aren't removed from the context associated with the class (see
2323 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2324 // live dependencies pointing to unloaded nmethods and causes a crash in
2325 // DC::remove_all_dependents() when it touches unloaded nmethod.
2326 dependencies().wipe();
2327
2328 #if INCLUDE_JVMTI
2329 // Deallocate breakpoint records
2330 if (breakpoints() != 0x0) {
2331 methods_do(clear_all_breakpoints);
2332 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2333 }
2334
2335 // deallocate the cached class file
2336 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2337 os::free(_cached_class_file);
2338 _cached_class_file = NULL;
2339 }
2340 #endif
2341
2342 // Decrement symbol reference counts associated with the unloaded class.
2343 if (_name != NULL) _name->decrement_refcount();
2344 // unreference array name derived from this class name (arrays of an unloaded
2345 // class can't be referenced anymore).
2346 if (_array_name != NULL) _array_name->decrement_refcount();
2347 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2348
2349 assert(_total_instanceKlass_count >= 1, "Sanity check");
2350 Atomic::dec(&_total_instanceKlass_count);
2351 }
2352
2353 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2354 if (array == NULL) {
2355 _source_debug_extension = NULL;
2356 } else {
2357 // Adding one to the attribute length in order to store a null terminator
2358 // character could cause an overflow because the attribute length is
2359 // already coded with an u4 in the classfile, but in practice, it's
2360 // unlikely to happen.
2361 assert((length+1) > length, "Overflow checking");
2362 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2363 for (int i = 0; i < length; i++) {
2364 sde[i] = array[i];
2365 }
2366 sde[length] = '\0';
2367 _source_debug_extension = sde;
2368 }
2369 }
2370
2371 address InstanceKlass::static_field_addr(int offset) {
2372 assert(offset >= InstanceMirrorKlass::offset_of_static_fields(), "has already been adjusted");
2373 return (address)(offset + cast_from_oop<intptr_t>(java_mirror()));
2374 }
2375
2376
2377 const char* InstanceKlass::signature_name() const {
2378 int hash_len = 0;
2379 char hash_buf[40];
2380
2381 // If this is an anonymous class, append a hash to make the name unique
2382 if (is_anonymous()) {
2383 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2384 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2385 hash_len = (int)strlen(hash_buf);
2386 }
2387
2388 // Get the internal name as a c string
2389 const char* src = (const char*) (name()->as_C_string());
2390 const int src_length = (int)strlen(src);
2391
2392 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2393
2394 // Add L as type indicator
2395 int dest_index = 0;
2396 dest[dest_index++] = is_value_type_klass() ? 'Q' : 'L';
2397
2398 // Add the actual class name
2399 for (int src_index = 0; src_index < src_length; ) {
2400 dest[dest_index++] = src[src_index++];
2401 }
2402
2403 // If we have a hash, append it
2404 for (int hash_index = 0; hash_index < hash_len; ) {
2405 dest[dest_index++] = hash_buf[hash_index++];
2406 }
2407
2408 // Add the semicolon and the NULL
2409 dest[dest_index++] = ';';
2410 dest[dest_index] = '\0';
2411 return dest;
2412 }
2413
2414 // Used to obtain the package name from a fully qualified class name.
2415 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2416 if (name == NULL) {
2417 return NULL;
2418 } else {
2419 if (name->utf8_length() <= 0) {
2420 return NULL;
2421 }
2422 ResourceMark rm;
2423 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2424 if (package_name == NULL) {
2425 return NULL;
2426 }
2427 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2428 return pkg_name;
2429 }
2430 }
2431
2432 ModuleEntry* InstanceKlass::module() const {
2433 if (!in_unnamed_package()) {
2434 return _package_entry->module();
2435 }
2436 const Klass* host = host_klass();
2437 if (host == NULL) {
2438 return class_loader_data()->unnamed_module();
2439 }
2440 return host->class_loader_data()->unnamed_module();
2441 }
2442
2443 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2444
2445 // ensure java/ packages only loaded by boot or platform builtin loaders
2446 Handle class_loader(THREAD, loader_data->class_loader());
2447 check_prohibited_package(name(), class_loader, CHECK);
2448
2449 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2450
2451 if (pkg_name != NULL && loader_data != NULL) {
2452
2453 // Find in class loader's package entry table.
2454 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2455
2456 // If the package name is not found in the loader's package
2457 // entry table, it is an indication that the package has not
2458 // been defined. Consider it defined within the unnamed module.
2459 if (_package_entry == NULL) {
2460 ResourceMark rm;
2461
2462 if (!ModuleEntryTable::javabase_defined()) {
2463 // Before java.base is defined during bootstrapping, define all packages in
2464 // the java.base module. If a non-java.base package is erroneously placed
2465 // in the java.base module it will be caught later when java.base
2466 // is defined by ModuleEntryTable::verify_javabase_packages check.
2467 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2468 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2469 } else {
2470 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2471 _package_entry = loader_data->packages()->lookup(pkg_name,
2472 loader_data->unnamed_module());
2473 }
2474
2475 // A package should have been successfully created
2476 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2477 name()->as_C_string(), loader_data->loader_name());
2478 }
2479
2480 if (log_is_enabled(Debug, module)) {
2481 ResourceMark rm;
2482 ModuleEntry* m = _package_entry->module();
2483 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2484 external_name(),
2485 pkg_name->as_C_string(),
2486 loader_data->loader_name(),
2487 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2488 }
2489 } else {
2490 ResourceMark rm;
2491 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2492 external_name(),
2493 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2494 UNNAMED_MODULE);
2495 }
2496 }
2497
2498
2499 // different versions of is_same_class_package
2500
2501 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2502 oop classloader1 = this->class_loader();
2503 PackageEntry* classpkg1 = this->package();
2504 if (class2->is_objArray_klass()) {
2505 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2506 }
2507
2508 oop classloader2;
2509 PackageEntry* classpkg2;
2510 if (class2->is_instance_klass()) {
2511 classloader2 = class2->class_loader();
2512 classpkg2 = class2->package();
2513 } else {
2514 assert(class2->is_typeArray_klass(), "should be type array");
2515 classloader2 = NULL;
2516 classpkg2 = NULL;
2517 }
2518
2519 // Same package is determined by comparing class loader
2520 // and package entries. Both must be the same. This rule
2521 // applies even to classes that are defined in the unnamed
2522 // package, they still must have the same class loader.
2523 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2524 return true;
2525 }
2526
2527 return false;
2528 }
2529
2530 // return true if this class and other_class are in the same package. Classloader
2531 // and classname information is enough to determine a class's package
2532 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2533 const Symbol* other_class_name) const {
2534 if (class_loader() != other_class_loader) {
2535 return false;
2536 }
2537 if (name()->fast_compare(other_class_name) == 0) {
2538 return true;
2539 }
2540
2541 {
2542 ResourceMark rm;
2543
2544 bool bad_class_name = false;
2545 const char* other_pkg =
2546 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2547 if (bad_class_name) {
2548 return false;
2549 }
2550 // Check that package_from_name() returns NULL, not "", if there is no package.
2551 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2552
2553 const Symbol* const this_package_name =
2554 this->package() != NULL ? this->package()->name() : NULL;
2555
2556 if (this_package_name == NULL || other_pkg == NULL) {
2557 // One of the two doesn't have a package. Only return true if the other
2558 // one also doesn't have a package.
2559 return (const char*)this_package_name == other_pkg;
2560 }
2561
2562 // Check if package is identical
2563 return this_package_name->equals(other_pkg);
2564 }
2565 }
2566
2567 // Returns true iff super_method can be overridden by a method in targetclassname
2568 // See JLS 3rd edition 8.4.6.1
2569 // Assumes name-signature match
2570 // "this" is InstanceKlass of super_method which must exist
2571 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2572 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2573 // Private methods can not be overridden
2574 if (super_method->is_private()) {
2575 return false;
2576 }
2577 // If super method is accessible, then override
2578 if ((super_method->is_protected()) ||
2579 (super_method->is_public())) {
2580 return true;
2581 }
2582 // Package-private methods are not inherited outside of package
2583 assert(super_method->is_package_private(), "must be package private");
2584 return(is_same_class_package(targetclassloader(), targetclassname));
2585 }
2586
2587 // Only boot and platform class loaders can define classes in "java/" packages.
2588 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2589 Handle class_loader,
2590 TRAPS) {
2591 if (!class_loader.is_null() &&
2592 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2593 class_name != NULL) {
2594 ResourceMark rm(THREAD);
2595 char* name = class_name->as_C_string();
2596 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2597 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2598 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2599 name = pkg_name->as_C_string();
2600 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2601 StringUtils::replace_no_expand(name, "/", ".");
2602 const char* msg_text1 = "Class loader (instance of): ";
2603 const char* msg_text2 = " tried to load prohibited package name: ";
2604 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2605 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2606 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2607 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2608 }
2609 }
2610 return;
2611 }
2612
2613 // tell if two classes have the same enclosing class (at package level)
2614 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2615 if (class2 == this) return true;
2616 if (!class2->is_instance_klass()) return false;
2617
2618 // must be in same package before we try anything else
2619 if (!is_same_class_package(class2))
2620 return false;
2621
2622 // As long as there is an outer_this.getEnclosingClass,
2623 // shift the search outward.
2624 const InstanceKlass* outer_this = this;
2625 for (;;) {
2626 // As we walk along, look for equalities between outer_this and class2.
2627 // Eventually, the walks will terminate as outer_this stops
2628 // at the top-level class around the original class.
2629 bool ignore_inner_is_member;
2630 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2631 CHECK_false);
2632 if (next == NULL) break;
2633 if (next == class2) return true;
2634 outer_this = InstanceKlass::cast(next);
2635 }
2636
2637 // Now do the same for class2.
2638 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2639 for (;;) {
2640 bool ignore_inner_is_member;
2641 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2642 CHECK_false);
2643 if (next == NULL) break;
2644 // Might as well check the new outer against all available values.
2645 if (next == this) return true;
2646 if (next == outer_this) return true;
2647 outer2 = InstanceKlass::cast(next);
2648 }
2649
2650 // If by this point we have not found an equality between the
2651 // two classes, we know they are in separate package members.
2652 return false;
2653 }
2654
2655 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2656 constantPoolHandle i_cp(THREAD, constants());
2657 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2658 int ioff = iter.inner_class_info_index();
2659 if (ioff != 0) {
2660 // Check to see if the name matches the class we're looking for
2661 // before attempting to find the class.
2662 if (i_cp->klass_name_at_matches(this, ioff)) {
2663 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2664 if (this == inner_klass) {
2665 *ooff = iter.outer_class_info_index();
2666 *noff = iter.inner_name_index();
2667 return true;
2668 }
2669 }
2670 }
2671 }
2672 return false;
2673 }
2674
2675 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2676 InstanceKlass* outer_klass = NULL;
2677 *inner_is_member = false;
2678 int ooff = 0, noff = 0;
2679 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2680 if (has_inner_classes_attr) {
2681 constantPoolHandle i_cp(THREAD, constants());
2682 if (ooff != 0) {
2683 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2684 outer_klass = InstanceKlass::cast(ok);
2685 *inner_is_member = true;
2686 }
2687 if (NULL == outer_klass) {
2688 // It may be anonymous; try for that.
2689 int encl_method_class_idx = enclosing_method_class_index();
2690 if (encl_method_class_idx != 0) {
2691 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2692 outer_klass = InstanceKlass::cast(ok);
2693 *inner_is_member = false;
2694 }
2695 }
2696 }
2697
2698 // If no inner class attribute found for this class.
2699 if (NULL == outer_klass) return NULL;
2700
2701 // Throws an exception if outer klass has not declared k as an inner klass
2702 // We need evidence that each klass knows about the other, or else
2703 // the system could allow a spoof of an inner class to gain access rights.
2704 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2705 return outer_klass;
2706 }
2707
2708 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2709 jint access = access_flags().as_int();
2710
2711 // But check if it happens to be member class.
2712 InnerClassesIterator iter(this);
2713 for (; !iter.done(); iter.next()) {
2714 int ioff = iter.inner_class_info_index();
2715 // Inner class attribute can be zero, skip it.
2716 // Strange but true: JVM spec. allows null inner class refs.
2717 if (ioff == 0) continue;
2718
2719 // only look at classes that are already loaded
2720 // since we are looking for the flags for our self.
2721 Symbol* inner_name = constants()->klass_name_at(ioff);
2722 if (name() == inner_name) {
2723 // This is really a member class.
2724 access = iter.inner_access_flags();
2725 break;
2726 }
2727 }
2728 // Remember to strip ACC_SUPER bit
2729 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2730 }
2731
2732 jint InstanceKlass::jvmti_class_status() const {
2733 jint result = 0;
2734
2735 if (is_linked()) {
2736 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2737 }
2738
2739 if (is_initialized()) {
2740 assert(is_linked(), "Class status is not consistent");
2741 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2742 }
2743 if (is_in_error_state()) {
2744 result |= JVMTI_CLASS_STATUS_ERROR;
2745 }
2746 return result;
2747 }
2748
2749 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2750 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2751 int method_table_offset_in_words = ioe->offset()/wordSize;
2752 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2753 / itableOffsetEntry::size();
2754
2755 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2756 // If the interface isn't implemented by the receiver class,
2757 // the VM should throw IncompatibleClassChangeError.
2758 if (cnt >= nof_interfaces) {
2759 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2760 }
2761
2762 Klass* ik = ioe->interface_klass();
2763 if (ik == holder) break;
2764 }
2765
2766 itableMethodEntry* ime = ioe->first_method_entry(this);
2767 Method* m = ime[index].method();
2768 if (m == NULL) {
2769 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2770 }
2771 return m;
2772 }
2773
2774
2775 #if INCLUDE_JVMTI
2776 // update default_methods for redefineclasses for methods that are
2777 // not yet in the vtable due to concurrent subclass define and superinterface
2778 // redefinition
2779 // Note: those in the vtable, should have been updated via adjust_method_entries
2780 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2781 // search the default_methods for uses of either obsolete or EMCP methods
2782 if (default_methods() != NULL) {
2783 for (int index = 0; index < default_methods()->length(); index ++) {
2784 Method* old_method = default_methods()->at(index);
2785 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2786 continue; // skip uninteresting entries
2787 }
2788 assert(!old_method->is_deleted(), "default methods may not be deleted");
2789
2790 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2791
2792 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2793 assert(old_method != new_method, "sanity check");
2794
2795 default_methods()->at_put(index, new_method);
2796 if (log_is_enabled(Info, redefine, class, update)) {
2797 ResourceMark rm;
2798 if (!(*trace_name_printed)) {
2799 log_info(redefine, class, update)
2800 ("adjust: klassname=%s default methods from name=%s",
2801 external_name(), old_method->method_holder()->external_name());
2802 *trace_name_printed = true;
2803 }
2804 log_debug(redefine, class, update, vtables)
2805 ("default method update: %s(%s) ",
2806 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2807 }
2808 }
2809 }
2810 }
2811 #endif // INCLUDE_JVMTI
2812
2813 // On-stack replacement stuff
2814 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2815 // only one compilation can be active
2816 {
2817 // This is a short non-blocking critical region, so the no safepoint check is ok.
2818 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2819 assert(n->is_osr_method(), "wrong kind of nmethod");
2820 n->set_osr_link(osr_nmethods_head());
2821 set_osr_nmethods_head(n);
2822 // Raise the highest osr level if necessary
2823 if (TieredCompilation) {
2824 Method* m = n->method();
2825 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2826 }
2827 }
2828
2829 // Get rid of the osr methods for the same bci that have lower levels.
2830 if (TieredCompilation) {
2831 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2832 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2833 if (inv != NULL && inv->is_in_use()) {
2834 inv->make_not_entrant();
2835 }
2836 }
2837 }
2838 }
2839
2840 // Remove osr nmethod from the list. Return true if found and removed.
2841 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2842 // This is a short non-blocking critical region, so the no safepoint check is ok.
2843 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2844 assert(n->is_osr_method(), "wrong kind of nmethod");
2845 nmethod* last = NULL;
2846 nmethod* cur = osr_nmethods_head();
2847 int max_level = CompLevel_none; // Find the max comp level excluding n
2848 Method* m = n->method();
2849 // Search for match
2850 bool found = false;
2851 while(cur != NULL && cur != n) {
2852 if (TieredCompilation && m == cur->method()) {
2853 // Find max level before n
2854 max_level = MAX2(max_level, cur->comp_level());
2855 }
2856 last = cur;
2857 cur = cur->osr_link();
2858 }
2859 nmethod* next = NULL;
2860 if (cur == n) {
2861 found = true;
2862 next = cur->osr_link();
2863 if (last == NULL) {
2864 // Remove first element
2865 set_osr_nmethods_head(next);
2866 } else {
2867 last->set_osr_link(next);
2868 }
2869 }
2870 n->set_osr_link(NULL);
2871 if (TieredCompilation) {
2872 cur = next;
2873 while (cur != NULL) {
2874 // Find max level after n
2875 if (m == cur->method()) {
2876 max_level = MAX2(max_level, cur->comp_level());
2877 }
2878 cur = cur->osr_link();
2879 }
2880 m->set_highest_osr_comp_level(max_level);
2881 }
2882 return found;
2883 }
2884
2885 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2886 // This is a short non-blocking critical region, so the no safepoint check is ok.
2887 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2888 nmethod* osr = osr_nmethods_head();
2889 int found = 0;
2890 while (osr != NULL) {
2891 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2892 if (osr->method() == m) {
2893 osr->mark_for_deoptimization();
2894 found++;
2895 }
2896 osr = osr->osr_link();
2897 }
2898 return found;
2899 }
2900
2901 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2902 // This is a short non-blocking critical region, so the no safepoint check is ok.
2903 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2904 nmethod* osr = osr_nmethods_head();
2905 nmethod* best = NULL;
2906 while (osr != NULL) {
2907 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2908 // There can be a time when a c1 osr method exists but we are waiting
2909 // for a c2 version. When c2 completes its osr nmethod we will trash
2910 // the c1 version and only be able to find the c2 version. However
2911 // while we overflow in the c1 code at back branches we don't want to
2912 // try and switch to the same code as we are already running
2913
2914 if (osr->method() == m &&
2915 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2916 if (match_level) {
2917 if (osr->comp_level() == comp_level) {
2918 // Found a match - return it.
2919 return osr;
2920 }
2921 } else {
2922 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2923 if (osr->comp_level() == CompLevel_highest_tier) {
2924 // Found the best possible - return it.
2925 return osr;
2926 }
2927 best = osr;
2928 }
2929 }
2930 }
2931 osr = osr->osr_link();
2932 }
2933 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2934 return best;
2935 }
2936 return NULL;
2937 }
2938
2939 // -----------------------------------------------------------------------------------------------------
2940 // Printing
2941
2942 #ifndef PRODUCT
2943
2944 #define BULLET " - "
2945
2946 static const char* state_names[] = {
2947 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2948 };
2949
2950 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
2951 ResourceMark rm;
2952 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
2953 for (int i = 0; i < len; i++) forward_refs[i] = 0;
2954 for (int i = 0; i < len; i++) {
2955 intptr_t e = start[i];
2956 st->print("%d : " INTPTR_FORMAT, i, e);
2957 if (forward_refs[i] != 0) {
2958 int from = forward_refs[i];
2959 int off = (int) start[from];
2960 st->print(" (offset %d <= [%d])", off, from);
2961 }
2962 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2963 st->print(" ");
2964 ((Metadata*)e)->print_value_on(st);
2965 } else if (self != NULL && e > 0 && e < 0x10000) {
2966 address location = self + e;
2967 int index = (int)((intptr_t*)location - start);
2968 st->print(" (offset %d => [%d])", (int)e, index);
2969 if (index >= 0 && index < len)
2970 forward_refs[index] = i;
2971 }
2972 st->cr();
2973 }
2974 }
2975
2976 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2977 return print_vtable(NULL, reinterpret_cast<intptr_t*>(start), len, st);
2978 }
2979
2980 template<typename T>
2981 static void print_array_on(outputStream* st, Array<T>* array) {
2982 if (array == NULL) { st->print_cr("NULL"); return; }
2983 array->print_value_on(st); st->cr();
2984 if (Verbose || WizardMode) {
2985 for (int i = 0; i < array->length(); i++) {
2986 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
2987 }
2988 }
2989 }
2990
2991 static void print_array_on(outputStream* st, Array<int>* array) {
2992 if (array == NULL) { st->print_cr("NULL"); return; }
2993 array->print_value_on(st); st->cr();
2994 if (Verbose || WizardMode) {
2995 for (int i = 0; i < array->length(); i++) {
2996 st->print("%d : %d", i, array->at(i)); st->cr();
2997 }
2998 }
2999 }
3000
3001 void InstanceKlass::print_on(outputStream* st) const {
3002 assert(is_klass(), "must be klass");
3003 Klass::print_on(st);
3004
3005 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3006 st->print(BULLET"klass size: %d", size()); st->cr();
3007 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3008 st->print(BULLET"misc flags: 0x%x", _misc_flags); st->cr();
3009 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3010 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3011 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
3012 st->print(BULLET"sub: ");
3013 Klass* sub = subklass();
3014 int n;
3015 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3016 if (n < MaxSubklassPrintSize) {
3017 sub->print_value_on(st);
3018 st->print(" ");
3019 }
3020 }
3021 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3022 st->cr();
3023
3024 if (is_interface()) {
3025 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3026 if (nof_implementors() == 1) {
3027 st->print_cr(BULLET"implementor: ");
3028 st->print(" ");
3029 implementor()->print_value_on(st);
3030 st->cr();
3031 }
3032 }
3033
3034 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
3035 st->print(BULLET"methods: "); print_array_on(st, methods());
3036 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3037 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3038 if (default_vtable_indices() != NULL) {
3039 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3040 }
3041 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3042 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3043 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3044 if (class_loader_data() != NULL) {
3045 st->print(BULLET"class loader data: ");
3046 class_loader_data()->print_value_on(st);
3047 st->cr();
3048 }
3049 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3050 if (source_file_name() != NULL) {
3051 st->print(BULLET"source file: ");
3052 source_file_name()->print_value_on(st);
3053 st->cr();
3054 }
3055 if (source_debug_extension() != NULL) {
3056 st->print(BULLET"source debug extension: ");
3057 st->print("%s", source_debug_extension());
3058 st->cr();
3059 }
3060 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3061 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3062 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3063 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3064 {
3065 bool have_pv = false;
3066 // previous versions are linked together through the InstanceKlass
3067 for (InstanceKlass* pv_node = previous_versions();
3068 pv_node != NULL;
3069 pv_node = pv_node->previous_versions()) {
3070 if (!have_pv)
3071 st->print(BULLET"previous version: ");
3072 have_pv = true;
3073 pv_node->constants()->print_value_on(st);
3074 }
3075 if (have_pv) st->cr();
3076 }
3077
3078 if (generic_signature() != NULL) {
3079 st->print(BULLET"generic signature: ");
3080 generic_signature()->print_value_on(st);
3081 st->cr();
3082 }
3083 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3084 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3085 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3086 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3087 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3088 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(NULL, start_of_itable(), itable_length(), st);
3089 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3090 FieldPrinter print_static_field(st);
3091 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3092 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3093 FieldPrinter print_nonstatic_field(st);
3094 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3095 ik->do_nonstatic_fields(&print_nonstatic_field);
3096
3097 st->print(BULLET"non-static oop maps: ");
3098 OopMapBlock* map = start_of_nonstatic_oop_maps();
3099 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3100 while (map < end_map) {
3101 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3102 map++;
3103 }
3104 st->cr();
3105 }
3106
3107 #endif //PRODUCT
3108
3109 void InstanceKlass::print_value_on(outputStream* st) const {
3110 assert(is_klass(), "must be klass");
3111 if (Verbose || WizardMode) access_flags().print_on(st);
3112 name()->print_value_on(st);
3113 }
3114
3115 #ifndef PRODUCT
3116
3117 void FieldPrinter::do_field(fieldDescriptor* fd) {
3118 _st->print(BULLET);
3119 if (_obj == NULL) {
3120 fd->print_on(_st);
3121 _st->cr();
3122 } else {
3123 fd->print_on_for(_st, _obj);
3124 _st->cr();
3125 }
3126 }
3127
3128
3129 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3130 Klass::oop_print_on(obj, st);
3131
3132 if (this == SystemDictionary::String_klass()) {
3133 typeArrayOop value = java_lang_String::value(obj);
3134 juint length = java_lang_String::length(obj);
3135 if (value != NULL &&
3136 value->is_typeArray() &&
3137 length <= (juint) value->length()) {
3138 st->print(BULLET"string: ");
3139 java_lang_String::print(obj, st);
3140 st->cr();
3141 if (!WizardMode) return; // that is enough
3142 }
3143 }
3144
3145 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3146 FieldPrinter print_field(st, obj);
3147 do_nonstatic_fields(&print_field);
3148
3149 if (this == SystemDictionary::Class_klass()) {
3150 st->print(BULLET"signature: ");
3151 java_lang_Class::print_signature(obj, st);
3152 st->cr();
3153 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3154 st->print(BULLET"fake entry for mirror: ");
3155 mirrored_klass->print_value_on_maybe_null(st);
3156 st->cr();
3157 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3158 st->print(BULLET"fake entry for array: ");
3159 array_klass->print_value_on_maybe_null(st);
3160 st->cr();
3161 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3162 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3163 Klass* real_klass = java_lang_Class::as_Klass(obj);
3164 if (real_klass != NULL && real_klass->is_instance_klass()) {
3165 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3166 }
3167 } else if (this == SystemDictionary::MethodType_klass()) {
3168 st->print(BULLET"signature: ");
3169 java_lang_invoke_MethodType::print_signature(obj, st);
3170 st->cr();
3171 }
3172 }
3173
3174 #endif //PRODUCT
3175
3176 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3177 st->print("a ");
3178 name()->print_value_on(st);
3179 obj->print_address_on(st);
3180 if (this == SystemDictionary::String_klass()
3181 && java_lang_String::value(obj) != NULL) {
3182 ResourceMark rm;
3183 int len = java_lang_String::length(obj);
3184 int plen = (len < 24 ? len : 12);
3185 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3186 st->print(" = \"%s\"", str);
3187 if (len > plen)
3188 st->print("...[%d]", len);
3189 } else if (this == SystemDictionary::Class_klass()) {
3190 Klass* k = java_lang_Class::as_Klass(obj);
3191 st->print(" = ");
3192 if (k != NULL) {
3193 k->print_value_on(st);
3194 } else {
3195 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3196 st->print("%s", tname ? tname : "type?");
3197 }
3198 } else if (this == SystemDictionary::MethodType_klass()) {
3199 st->print(" = ");
3200 java_lang_invoke_MethodType::print_signature(obj, st);
3201 } else if (java_lang_boxing_object::is_instance(obj)) {
3202 st->print(" = ");
3203 java_lang_boxing_object::print(obj, st);
3204 } else if (this == SystemDictionary::LambdaForm_klass()) {
3205 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3206 if (vmentry != NULL) {
3207 st->print(" => ");
3208 vmentry->print_value_on(st);
3209 }
3210 } else if (this == SystemDictionary::MemberName_klass()) {
3211 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3212 if (vmtarget != NULL) {
3213 st->print(" = ");
3214 vmtarget->print_value_on(st);
3215 } else {
3216 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3217 st->print(".");
3218 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3219 }
3220 }
3221 }
3222
3223 const char* InstanceKlass::internal_name() const {
3224 return external_name();
3225 }
3226
3227 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3228 const char* module_name,
3229 const ClassFileStream* cfs) const {
3230 if (!log_is_enabled(Info, class, load)) {
3231 return;
3232 }
3233
3234 ResourceMark rm;
3235 LogMessage(class, load) msg;
3236 stringStream info_stream;
3237
3238 // Name and class hierarchy info
3239 info_stream.print("%s", external_name());
3240
3241 // Source
3242 if (cfs != NULL) {
3243 if (cfs->source() != NULL) {
3244 if (module_name != NULL) {
3245 if (ClassLoader::is_modules_image(cfs->source())) {
3246 info_stream.print(" source: jrt:/%s", module_name);
3247 } else {
3248 info_stream.print(" source: %s", cfs->source());
3249 }
3250 } else {
3251 info_stream.print(" source: %s", cfs->source());
3252 }
3253 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3254 Thread* THREAD = Thread::current();
3255 Klass* caller =
3256 THREAD->is_Java_thread()
3257 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3258 : NULL;
3259 // caller can be NULL, for example, during a JVMTI VM_Init hook
3260 if (caller != NULL) {
3261 info_stream.print(" source: instance of %s", caller->external_name());
3262 } else {
3263 // source is unknown
3264 }
3265 } else {
3266 oop class_loader = loader_data->class_loader();
3267 info_stream.print(" source: %s", class_loader->klass()->external_name());
3268 }
3269 } else {
3270 info_stream.print(" source: shared objects file");
3271 }
3272
3273 msg.info("%s", info_stream.as_string());
3274
3275 if (log_is_enabled(Debug, class, load)) {
3276 stringStream debug_stream;
3277
3278 // Class hierarchy info
3279 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3280 p2i(this), p2i(superklass()));
3281
3282 // Interfaces
3283 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3284 debug_stream.print(" interfaces:");
3285 int length = local_interfaces()->length();
3286 for (int i = 0; i < length; i++) {
3287 debug_stream.print(" " INTPTR_FORMAT,
3288 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3289 }
3290 }
3291
3292 // Class loader
3293 debug_stream.print(" loader: [");
3294 loader_data->print_value_on(&debug_stream);
3295 debug_stream.print("]");
3296
3297 // Classfile checksum
3298 if (cfs) {
3299 debug_stream.print(" bytes: %d checksum: %08x",
3300 cfs->length(),
3301 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3302 cfs->length()));
3303 }
3304
3305 msg.debug("%s", debug_stream.as_string());
3306 }
3307 }
3308
3309 #if INCLUDE_SERVICES
3310 // Size Statistics
3311 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3312 Klass::collect_statistics(sz);
3313
3314 sz->_inst_size = wordSize * size_helper();
3315 sz->_vtab_bytes = wordSize * vtable_length();
3316 sz->_itab_bytes = wordSize * itable_length();
3317 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3318
3319 int n = 0;
3320 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3321 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3322 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3323 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3324 n += (sz->_fields_bytes = sz->count_array(fields()));
3325 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3326 sz->_ro_bytes += n;
3327
3328 const ConstantPool* cp = constants();
3329 if (cp) {
3330 cp->collect_statistics(sz);
3331 }
3332
3333 const Annotations* anno = annotations();
3334 if (anno) {
3335 anno->collect_statistics(sz);
3336 }
3337
3338 const Array<Method*>* methods_array = methods();
3339 if (methods()) {
3340 for (int i = 0; i < methods_array->length(); i++) {
3341 Method* method = methods_array->at(i);
3342 if (method) {
3343 sz->_method_count ++;
3344 method->collect_statistics(sz);
3345 }
3346 }
3347 }
3348 }
3349 #endif // INCLUDE_SERVICES
3350
3351 // Verification
3352
3353 class VerifyFieldClosure: public OopClosure {
3354 protected:
3355 template <class T> void do_oop_work(T* p) {
3356 oop obj = oopDesc::load_decode_heap_oop(p);
3357 if (!oopDesc::is_oop_or_null(obj)) {
3358 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3359 Universe::print_on(tty);
3360 guarantee(false, "boom");
3361 }
3362 }
3363 public:
3364 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3365 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3366 };
3367
3368 void InstanceKlass::verify_on(outputStream* st) {
3369 #ifndef PRODUCT
3370 // Avoid redundant verifies, this really should be in product.
3371 if (_verify_count == Universe::verify_count()) return;
3372 _verify_count = Universe::verify_count();
3373 #endif
3374
3375 // Verify Klass
3376 Klass::verify_on(st);
3377
3378 // Verify that klass is present in ClassLoaderData
3379 guarantee(class_loader_data()->contains_klass(this),
3380 "this class isn't found in class loader data");
3381
3382 // Verify vtables
3383 if (is_linked()) {
3384 // $$$ This used to be done only for m/s collections. Doing it
3385 // always seemed a valid generalization. (DLD -- 6/00)
3386 vtable().verify(st);
3387 }
3388
3389 // Verify first subklass
3390 if (subklass() != NULL) {
3391 guarantee(subklass()->is_klass(), "should be klass");
3392 }
3393
3394 // Verify siblings
3395 Klass* super = this->super();
3396 Klass* sib = next_sibling();
3397 if (sib != NULL) {
3398 if (sib == this) {
3399 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3400 }
3401
3402 guarantee(sib->is_klass(), "should be klass");
3403 guarantee(sib->super() == super, "siblings should have same superklass");
3404 }
3405
3406 // Verify implementor fields
3407 Klass* im = implementor();
3408 if (im != NULL) {
3409 guarantee(is_interface(), "only interfaces should have implementor set");
3410 guarantee(im->is_klass(), "should be klass");
3411 guarantee(!im->is_interface() || im == this,
3412 "implementors cannot be interfaces");
3413 }
3414
3415 // Verify local interfaces
3416 if (local_interfaces()) {
3417 Array<Klass*>* local_interfaces = this->local_interfaces();
3418 for (int j = 0; j < local_interfaces->length(); j++) {
3419 Klass* e = local_interfaces->at(j);
3420 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3421 }
3422 }
3423
3424 // Verify transitive interfaces
3425 if (transitive_interfaces() != NULL) {
3426 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3427 for (int j = 0; j < transitive_interfaces->length(); j++) {
3428 Klass* e = transitive_interfaces->at(j);
3429 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3430 }
3431 }
3432
3433 // Verify methods
3434 if (methods() != NULL) {
3435 Array<Method*>* methods = this->methods();
3436 for (int j = 0; j < methods->length(); j++) {
3437 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3438 }
3439 for (int j = 0; j < methods->length() - 1; j++) {
3440 Method* m1 = methods->at(j);
3441 Method* m2 = methods->at(j + 1);
3442 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3443 }
3444 }
3445
3446 // Verify method ordering
3447 if (method_ordering() != NULL) {
3448 Array<int>* method_ordering = this->method_ordering();
3449 int length = method_ordering->length();
3450 if (JvmtiExport::can_maintain_original_method_order() ||
3451 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3452 guarantee(length == methods()->length(), "invalid method ordering length");
3453 jlong sum = 0;
3454 for (int j = 0; j < length; j++) {
3455 int original_index = method_ordering->at(j);
3456 guarantee(original_index >= 0, "invalid method ordering index");
3457 guarantee(original_index < length, "invalid method ordering index");
3458 sum += original_index;
3459 }
3460 // Verify sum of indices 0,1,...,length-1
3461 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3462 } else {
3463 guarantee(length == 0, "invalid method ordering length");
3464 }
3465 }
3466
3467 // Verify default methods
3468 if (default_methods() != NULL) {
3469 Array<Method*>* methods = this->default_methods();
3470 for (int j = 0; j < methods->length(); j++) {
3471 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3472 }
3473 for (int j = 0; j < methods->length() - 1; j++) {
3474 Method* m1 = methods->at(j);
3475 Method* m2 = methods->at(j + 1);
3476 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3477 }
3478 }
3479
3480 // Verify JNI static field identifiers
3481 if (jni_ids() != NULL) {
3482 jni_ids()->verify(this);
3483 }
3484
3485 // Verify other fields
3486 if (array_klasses() != NULL) {
3487 guarantee(array_klasses()->is_klass(), "should be klass");
3488 }
3489 if (constants() != NULL) {
3490 guarantee(constants()->is_constantPool(), "should be constant pool");
3491 }
3492 const Klass* host = host_klass();
3493 if (host != NULL) {
3494 guarantee(host->is_klass(), "should be klass");
3495 }
3496 }
3497
3498 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3499 Klass::oop_verify_on(obj, st);
3500 VerifyFieldClosure blk;
3501 obj->oop_iterate_no_header(&blk);
3502 }
3503
3504
3505 // JNIid class for jfieldIDs only
3506 // Note to reviewers:
3507 // These JNI functions are just moved over to column 1 and not changed
3508 // in the compressed oops workspace.
3509 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3510 _holder = holder;
3511 _offset = offset;
3512 _next = next;
3513 debug_only(_is_static_field_id = false;)
3514 }
3515
3516
3517 JNIid* JNIid::find(int offset) {
3518 JNIid* current = this;
3519 while (current != NULL) {
3520 if (current->offset() == offset) return current;
3521 current = current->next();
3522 }
3523 return NULL;
3524 }
3525
3526 void JNIid::deallocate(JNIid* current) {
3527 while (current != NULL) {
3528 JNIid* next = current->next();
3529 delete current;
3530 current = next;
3531 }
3532 }
3533
3534
3535 void JNIid::verify(Klass* holder) {
3536 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3537 int end_field_offset;
3538 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3539
3540 JNIid* current = this;
3541 while (current != NULL) {
3542 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3543 #ifdef ASSERT
3544 int o = current->offset();
3545 if (current->is_static_field_id()) {
3546 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3547 }
3548 #endif
3549 current = current->next();
3550 }
3551 }
3552
3553 oop InstanceKlass::klass_holder_phantom() {
3554 oop* addr;
3555 if (is_anonymous()) {
3556 addr = _java_mirror.ptr_raw();
3557 } else {
3558 addr = &class_loader_data()->_class_loader;
3559 }
3560 return RootAccess<IN_CONCURRENT_ROOT | ON_PHANTOM_OOP_REF>::oop_load(addr);
3561 }
3562
3563 #ifdef ASSERT
3564 void InstanceKlass::set_init_state(ClassState state) {
3565 bool good_state = is_shared() ? (_init_state <= state)
3566 : (_init_state < state);
3567 assert(good_state || state == allocated, "illegal state transition");
3568 _init_state = (u1)state;
3569 }
3570 #endif
3571
3572 #if INCLUDE_JVMTI
3573
3574 // RedefineClasses() support for previous versions
3575
3576 // Globally, there is at least one previous version of a class to walk
3577 // during class unloading, which is saved because old methods in the class
3578 // are still running. Otherwise the previous version list is cleaned up.
3579 bool InstanceKlass::_has_previous_versions = false;
3580
3581 // Returns true if there are previous versions of a class for class
3582 // unloading only. Also resets the flag to false. purge_previous_version
3583 // will set the flag to true if there are any left, i.e., if there's any
3584 // work to do for next time. This is to avoid the expensive code cache
3585 // walk in CLDG::do_unloading().
3586 bool InstanceKlass::has_previous_versions_and_reset() {
3587 bool ret = _has_previous_versions;
3588 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3589 ret ? "true" : "false");
3590 _has_previous_versions = false;
3591 return ret;
3592 }
3593
3594 // Purge previous versions before adding new previous versions of the class and
3595 // during class unloading.
3596 void InstanceKlass::purge_previous_version_list() {
3597 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3598 assert(has_been_redefined(), "Should only be called for main class");
3599
3600 // Quick exit.
3601 if (previous_versions() == NULL) {
3602 return;
3603 }
3604
3605 // This klass has previous versions so see what we can cleanup
3606 // while it is safe to do so.
3607
3608 int deleted_count = 0; // leave debugging breadcrumbs
3609 int live_count = 0;
3610 ClassLoaderData* loader_data = class_loader_data();
3611 assert(loader_data != NULL, "should never be null");
3612
3613 ResourceMark rm;
3614 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3615
3616 // previous versions are linked together through the InstanceKlass
3617 InstanceKlass* pv_node = previous_versions();
3618 InstanceKlass* last = this;
3619 int version = 0;
3620
3621 // check the previous versions list
3622 for (; pv_node != NULL; ) {
3623
3624 ConstantPool* pvcp = pv_node->constants();
3625 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3626
3627 if (!pvcp->on_stack()) {
3628 // If the constant pool isn't on stack, none of the methods
3629 // are executing. Unlink this previous_version.
3630 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3631 // so will be deallocated during the next phase of class unloading.
3632 log_trace(redefine, class, iklass, purge)
3633 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3634 // For debugging purposes.
3635 pv_node->set_is_scratch_class();
3636 // Unlink from previous version list.
3637 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3638 InstanceKlass* next = pv_node->previous_versions();
3639 pv_node->link_previous_versions(NULL); // point next to NULL
3640 last->link_previous_versions(next);
3641 // Add to the deallocate list after unlinking
3642 loader_data->add_to_deallocate_list(pv_node);
3643 pv_node = next;
3644 deleted_count++;
3645 version++;
3646 continue;
3647 } else {
3648 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3649 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3650 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3651 live_count++;
3652 // found a previous version for next time we do class unloading
3653 _has_previous_versions = true;
3654 }
3655
3656 // At least one method is live in this previous version.
3657 // Reset dead EMCP methods not to get breakpoints.
3658 // All methods are deallocated when all of the methods for this class are no
3659 // longer running.
3660 Array<Method*>* method_refs = pv_node->methods();
3661 if (method_refs != NULL) {
3662 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3663 for (int j = 0; j < method_refs->length(); j++) {
3664 Method* method = method_refs->at(j);
3665
3666 if (!method->on_stack()) {
3667 // no breakpoints for non-running methods
3668 if (method->is_running_emcp()) {
3669 method->set_running_emcp(false);
3670 }
3671 } else {
3672 assert (method->is_obsolete() || method->is_running_emcp(),
3673 "emcp method cannot run after emcp bit is cleared");
3674 log_trace(redefine, class, iklass, purge)
3675 ("purge: %s(%s): prev method @%d in version @%d is alive",
3676 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3677 }
3678 }
3679 }
3680 // next previous version
3681 last = pv_node;
3682 pv_node = pv_node->previous_versions();
3683 version++;
3684 }
3685 log_trace(redefine, class, iklass, purge)
3686 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3687 }
3688
3689 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3690 int emcp_method_count) {
3691 int obsolete_method_count = old_methods->length() - emcp_method_count;
3692
3693 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3694 _previous_versions != NULL) {
3695 // We have a mix of obsolete and EMCP methods so we have to
3696 // clear out any matching EMCP method entries the hard way.
3697 int local_count = 0;
3698 for (int i = 0; i < old_methods->length(); i++) {
3699 Method* old_method = old_methods->at(i);
3700 if (old_method->is_obsolete()) {
3701 // only obsolete methods are interesting
3702 Symbol* m_name = old_method->name();
3703 Symbol* m_signature = old_method->signature();
3704
3705 // previous versions are linked together through the InstanceKlass
3706 int j = 0;
3707 for (InstanceKlass* prev_version = _previous_versions;
3708 prev_version != NULL;
3709 prev_version = prev_version->previous_versions(), j++) {
3710
3711 Array<Method*>* method_refs = prev_version->methods();
3712 for (int k = 0; k < method_refs->length(); k++) {
3713 Method* method = method_refs->at(k);
3714
3715 if (!method->is_obsolete() &&
3716 method->name() == m_name &&
3717 method->signature() == m_signature) {
3718 // The current RedefineClasses() call has made all EMCP
3719 // versions of this method obsolete so mark it as obsolete
3720 log_trace(redefine, class, iklass, add)
3721 ("%s(%s): flush obsolete method @%d in version @%d",
3722 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3723
3724 method->set_is_obsolete();
3725 break;
3726 }
3727 }
3728
3729 // The previous loop may not find a matching EMCP method, but
3730 // that doesn't mean that we can optimize and not go any
3731 // further back in the PreviousVersion generations. The EMCP
3732 // method for this generation could have already been made obsolete,
3733 // but there still may be an older EMCP method that has not
3734 // been made obsolete.
3735 }
3736
3737 if (++local_count >= obsolete_method_count) {
3738 // no more obsolete methods so bail out now
3739 break;
3740 }
3741 }
3742 }
3743 }
3744 }
3745
3746 // Save the scratch_class as the previous version if any of the methods are running.
3747 // The previous_versions are used to set breakpoints in EMCP methods and they are
3748 // also used to clean MethodData links to redefined methods that are no longer running.
3749 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3750 int emcp_method_count) {
3751 assert(Thread::current()->is_VM_thread(),
3752 "only VMThread can add previous versions");
3753
3754 ResourceMark rm;
3755 log_trace(redefine, class, iklass, add)
3756 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3757
3758 // Clean out old previous versions for this class
3759 purge_previous_version_list();
3760
3761 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3762 // a previous redefinition may be made obsolete by this redefinition.
3763 Array<Method*>* old_methods = scratch_class->methods();
3764 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3765
3766 // If the constant pool for this previous version of the class
3767 // is not marked as being on the stack, then none of the methods
3768 // in this previous version of the class are on the stack so
3769 // we don't need to add this as a previous version.
3770 ConstantPool* cp_ref = scratch_class->constants();
3771 if (!cp_ref->on_stack()) {
3772 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3773 // For debugging purposes.
3774 scratch_class->set_is_scratch_class();
3775 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3776 return;
3777 }
3778
3779 if (emcp_method_count != 0) {
3780 // At least one method is still running, check for EMCP methods
3781 for (int i = 0; i < old_methods->length(); i++) {
3782 Method* old_method = old_methods->at(i);
3783 if (!old_method->is_obsolete() && old_method->on_stack()) {
3784 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3785 // we can add breakpoints for it.
3786
3787 // We set the method->on_stack bit during safepoints for class redefinition
3788 // and use this bit to set the is_running_emcp bit.
3789 // After the safepoint, the on_stack bit is cleared and the running emcp
3790 // method may exit. If so, we would set a breakpoint in a method that
3791 // is never reached, but this won't be noticeable to the programmer.
3792 old_method->set_running_emcp(true);
3793 log_trace(redefine, class, iklass, add)
3794 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3795 } else if (!old_method->is_obsolete()) {
3796 log_trace(redefine, class, iklass, add)
3797 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3798 }
3799 }
3800 }
3801
3802 // Add previous version if any methods are still running.
3803 // Set has_previous_version flag for processing during class unloading.
3804 _has_previous_versions = true;
3805 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3806 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3807 scratch_class->link_previous_versions(previous_versions());
3808 link_previous_versions(scratch_class);
3809 } // end add_previous_version()
3810
3811 #endif // INCLUDE_JVMTI
3812
3813 Method* InstanceKlass::method_with_idnum(int idnum) {
3814 Method* m = NULL;
3815 if (idnum < methods()->length()) {
3816 m = methods()->at(idnum);
3817 }
3818 if (m == NULL || m->method_idnum() != idnum) {
3819 for (int index = 0; index < methods()->length(); ++index) {
3820 m = methods()->at(index);
3821 if (m->method_idnum() == idnum) {
3822 return m;
3823 }
3824 }
3825 // None found, return null for the caller to handle.
3826 return NULL;
3827 }
3828 return m;
3829 }
3830
3831
3832 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3833 if (idnum >= methods()->length()) {
3834 return NULL;
3835 }
3836 Method* m = methods()->at(idnum);
3837 if (m != NULL && m->orig_method_idnum() == idnum) {
3838 return m;
3839 }
3840 // Obsolete method idnum does not match the original idnum
3841 for (int index = 0; index < methods()->length(); ++index) {
3842 m = methods()->at(index);
3843 if (m->orig_method_idnum() == idnum) {
3844 return m;
3845 }
3846 }
3847 // None found, return null for the caller to handle.
3848 return NULL;
3849 }
3850
3851
3852 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3853 InstanceKlass* holder = get_klass_version(version);
3854 if (holder == NULL) {
3855 return NULL; // The version of klass is gone, no method is found
3856 }
3857 Method* method = holder->method_with_orig_idnum(idnum);
3858 return method;
3859 }
3860
3861 #if INCLUDE_JVMTI
3862 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3863 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3864 // Ignore the archived class stream data
3865 return NULL;
3866 } else {
3867 return _cached_class_file;
3868 }
3869 }
3870
3871 jint InstanceKlass::get_cached_class_file_len() {
3872 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3873 }
3874
3875 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3876 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3877 }
3878
3879 #if INCLUDE_CDS
3880 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3881 if (DumpSharedSpaces) {
3882 return _cached_class_file;
3883 } else {
3884 assert(this->is_shared(), "class should be shared");
3885 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3886 return _cached_class_file;
3887 } else {
3888 return NULL;
3889 }
3890 }
3891 }
3892 #endif
3893 #endif
3894
3895 #define THROW_DVT_ERROR(s) \
3896 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_IncompatibleClassChangeError(), \
3897 "ValueCapableClass class '%s' %s", external_name(),(s)); \
3898 return
3899
3900 void InstanceKlass::create_value_capable_class(Handle class_loader, Handle protection_domain, TRAPS) {
3901 ResourceMark rm(THREAD);
3902 HandleMark hm(THREAD);
3903
3904 if (!EnableMVT) {
3905 return; // Silent fail
3906 }
3907 // Validate VCC...
3908 if (!has_nonstatic_fields()) {
3909 THROW_DVT_ERROR("has no instance fields");
3910 }
3911 if (is_value()) {
3912 THROW_DVT_ERROR("is already a value type");
3913 }
3914 if (!access_flags().is_final()) {
3915 THROW_DVT_ERROR("is not a final class");
3916 }
3917 if (super() != SystemDictionary::Object_klass()) {
3918 THROW_DVT_ERROR("does not derive from Object only");
3919 }
3920
3921 // All non-static are final
3922 GrowableArray<Handle>* fields = new GrowableArray<Handle>(THREAD, java_fields_count()*2);
3923 GrowableArray<jint>* fields_access = new GrowableArray<jint>(THREAD, java_fields_count()*2);
3924 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
3925 AccessFlags access_flags = fs.access_flags();
3926 if (access_flags.is_static()) {
3927 continue;
3928 }
3929 if (!access_flags.is_final()) {
3930 THROW_DVT_ERROR("contains non-final instance field");
3931 }
3932 jint flags = access_flags.get_flags();
3933 // Remember the field name, signature, access modifiers
3934 Handle h = java_lang_String::create_from_symbol(fs.name(), CHECK);
3935 fields->append(h);
3936 h = java_lang_String::create_from_symbol(fs.signature(), CHECK);
3937 fields->append(h);
3938 fields_access->append(access_flags.get_flags());
3939 }
3940
3941 // Generate DVT...
3942 log_debug(load)("Cooking DVT for VCC %s", external_name());
3943 const char* this_name = name()->as_C_string();
3944
3945 // Assemble the Java args...field descriptor array
3946 objArrayOop fdarr_oop = oopFactory::new_objectArray(fields->length(), CHECK);
3947 objArrayHandle fdarr(THREAD, fdarr_oop);
3948 for (int i = 0; i < fields->length(); i++) {
3949 fdarr->obj_at_put(i, fields->at(i)());
3950 }
3951 //...field access modifiers array
3952 typeArrayOop faarr_oop = oopFactory::new_intArray(fields_access->length(), CHECK);
3953 typeArrayHandle faarr(THREAD, faarr_oop);
3954 for (int i = 0; i < fields_access->length(); i++) {
3955 faarr->int_at_put(i, fields_access->at(i));
3956 }
3957
3958 Handle vcc_name_h = java_lang_String::create_from_symbol(name(), CHECK);
3959 // Upcall to our Java helper...
3960 JavaValue result(T_OBJECT);
3961 JavaCallArguments args(5);
3962 args.push_oop(vcc_name_h);
3963 args.push_oop(class_loader);
3964 args.push_oop(protection_domain);
3965 args.push_oop(fdarr);
3966 args.push_oop(faarr);
3967 JavaCalls::call_static(&result,
3968 SystemDictionary::Valhalla_MVT1_0_klass(),
3969 vmSymbols::valhalla_shady_MVT1_0_createDerivedValueType(),
3970 vmSymbols::valhalla_shady_MVT1_0_createDerivedValueType_signature(),
3971 &args,
3972 CHECK);
3973 Handle returned(THREAD, (oop) result.get_jobject());
3974 if (returned.is_null()) {
3975 THROW_DVT_ERROR("unknown error deriving value type");
3976 }
3977 TempNewSymbol dvt_name_sym = java_lang_String::as_symbol(returned(), CHECK);
3978
3979 Klass* dvt_klass = SystemDictionary::resolve_or_null(dvt_name_sym,
3980 class_loader,
3981 protection_domain,
3982 CHECK);
3983 if (!dvt_klass->is_value()) {
3984 THROW_DVT_ERROR("failed to resolve derived value type");
3985 }
3986 /**
3987 * Found it, let's point to each other to denote "is_derive_vt()"...
3988 */
3989 ValueKlass* vt_klass = ValueKlass::cast(dvt_klass);
3990 assert(vt_klass->class_loader() == class_loader(), "DVT Not the same class loader as VCC");
3991 vt_klass->set_vcc_klass(this);
3992 log_debug(load)("Cooked DVT %s for VCC %s", vt_klass->external_name(), external_name());
3993 }
3994