1 /*
2 * Copyright (c) 1997, 2017, 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 "aot/aotLoader.hpp"
27 #include "classfile/classFileParser.hpp"
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/javaClasses.hpp"
31 #include "classfile/moduleEntry.hpp"
32 #include "classfile/systemDictionary.hpp"
33 #include "classfile/systemDictionaryShared.hpp"
34 #include "classfile/verifier.hpp"
35 #include "classfile/vmSymbols.hpp"
36 #include "code/dependencyContext.hpp"
37 #include "compiler/compileBroker.hpp"
38 #include "gc/shared/collectedHeap.inline.hpp"
39 #include "gc/shared/specialized_oop_closures.hpp"
40 #include "interpreter/oopMapCache.hpp"
41 #include "interpreter/rewriter.hpp"
42 #include "jvmtifiles/jvmti.h"
43 #include "logging/log.hpp"
44 #include "logging/logMessage.hpp"
45 #include "memory/heapInspection.hpp"
46 #include "memory/iterator.inline.hpp"
47 #include "memory/metadataFactory.hpp"
48 #include "memory/metaspaceShared.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "oops/fieldStreams.hpp"
52 #include "oops/instanceClassLoaderKlass.hpp"
53 #include "oops/instanceKlass.inline.hpp"
54 #include "oops/instanceMirrorKlass.hpp"
55 #include "oops/instanceOop.hpp"
56 #include "oops/klass.inline.hpp"
57 #include "oops/method.hpp"
58 #include "oops/oop.inline.hpp"
59 #include "oops/symbol.hpp"
60 #include "oops/valueKlass.hpp"
61 #include "prims/jvmtiExport.hpp"
62 #include "prims/jvmtiRedefineClasses.hpp"
63 #include "prims/jvmtiThreadState.hpp"
64 #include "prims/methodComparator.hpp"
65 #include "runtime/atomic.hpp"
66 #include "runtime/fieldDescriptor.hpp"
67 #include "runtime/handles.inline.hpp"
68 #include "runtime/javaCalls.hpp"
69 #include "runtime/mutexLocker.hpp"
70 #include "runtime/orderAccess.inline.hpp"
71 #include "runtime/thread.inline.hpp"
72 #include "services/classLoadingService.hpp"
73 #include "services/threadService.hpp"
74 #include "utilities/dtrace.hpp"
75 #include "utilities/macros.hpp"
76 #include "utilities/stringUtils.hpp"
77 #ifdef COMPILER1
78 #include "c1/c1_Compiler.hpp"
79 #endif
80
81 #ifdef DTRACE_ENABLED
82
83
84 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
85 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
86 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
87 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
88 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
89 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
90 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
91 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
92 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
93 { \
94 char* data = NULL; \
95 int len = 0; \
96 Symbol* clss_name = name(); \
97 if (clss_name != NULL) { \
98 data = (char*)clss_name->bytes(); \
99 len = clss_name->utf8_length(); \
100 } \
101 HOTSPOT_CLASS_INITIALIZATION_##type( \
102 data, len, class_loader(), thread_type); \
103 }
104
105 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
106 { \
107 char* data = NULL; \
108 int len = 0; \
109 Symbol* clss_name = name(); \
110 if (clss_name != NULL) { \
111 data = (char*)clss_name->bytes(); \
112 len = clss_name->utf8_length(); \
113 } \
114 HOTSPOT_CLASS_INITIALIZATION_##type( \
115 data, len, class_loader(), thread_type, wait); \
116 }
117
118 #else // ndef DTRACE_ENABLED
119
120 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
121 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
122
123 #endif // ndef DTRACE_ENABLED
124
125 volatile int InstanceKlass::_total_instanceKlass_count = 0;
126
127 static inline bool is_class_loader(const Symbol* class_name,
128 const ClassFileParser& parser) {
129 assert(class_name != NULL, "invariant");
130
131 if (class_name == vmSymbols::java_lang_ClassLoader()) {
132 return true;
133 }
134
135 if (SystemDictionary::ClassLoader_klass_loaded()) {
136 const Klass* const super_klass = parser.super_klass();
137 if (super_klass != NULL) {
138 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
139 return true;
140 }
141 }
142 }
143 return false;
144 }
145
146 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
147 const int size = InstanceKlass::size(parser.vtable_size(),
148 parser.itable_size(),
149 nonstatic_oop_map_size(parser.total_oop_map_count()),
150 parser.is_interface(),
151 parser.is_anonymous(),
152 should_store_fingerprint(),
153 parser.has_value_fields() ? parser.java_fields_count() : 0,
154 parser.is_value_type());
155
156 const Symbol* const class_name = parser.class_name();
157 assert(class_name != NULL, "invariant");
158 ClassLoaderData* loader_data = parser.loader_data();
159 assert(loader_data != NULL, "invariant");
160
161 InstanceKlass* ik;
162
163 // Allocation
164 if (REF_NONE == parser.reference_type()) {
165 if (class_name == vmSymbols::java_lang_Class()) {
166 // mirror
167 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
168 }
169 else if (is_class_loader(class_name, parser)) {
170 // class loader
171 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
172 } else if (parser.is_value_type()) {
173 // value type
174 ik = new (loader_data, size, THREAD) ValueKlass(parser);
175 } else {
176 // normal
177 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
178 }
179 }
180 else {
181 // reference
182 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
183 }
184
185 // Check for pending exception before adding to the loader data and incrementing
186 // class count. Can get OOM here.
187 if (HAS_PENDING_EXCEPTION) {
188 return NULL;
189 }
190
191 assert(ik != NULL, "invariant");
192
193 const bool publicize = !parser.is_internal();
194 #ifdef ASSERT
195 assert(ik->size() == size, "");
196 ik->bounds_check((address) ik->start_of_vtable(), false, size);
197 ik->bounds_check((address) ik->start_of_itable(), false, size);
198 ik->bounds_check((address) ik->end_of_itable(), true, size);
199 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
200 #endif //ASSERT
201
202 // Add all classes to our internal class loader list here,
203 // including classes in the bootstrap (NULL) class loader.
204 loader_data->add_class(ik, publicize);
205 Atomic::inc(&_total_instanceKlass_count);
206
207 return ik;
208 }
209
210 #ifndef PRODUCT
211 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
212 const char* bad = NULL;
213 address end = NULL;
214 if (addr < (address)this) {
215 bad = "before";
216 } else if (addr == (address)this) {
217 if (edge_ok) return true;
218 bad = "just before";
219 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
220 if (edge_ok) return true;
221 bad = "just after";
222 } else if (addr > end) {
223 bad = "after";
224 } else {
225 return true;
226 }
227 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
228 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
229 Verbose = WizardMode = true; this->print(); //@@
230 return false;
231 }
232 #endif //PRODUCT
233
234 // copy method ordering from resource area to Metaspace
235 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
236 if (m != NULL) {
237 // allocate a new array and copy contents (memcpy?)
238 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
239 for (int i = 0; i < m->length(); i++) {
240 _method_ordering->at_put(i, m->at(i));
241 }
242 } else {
243 _method_ordering = Universe::the_empty_int_array();
244 }
245 }
246
247 // create a new array of vtable_indices for default methods
248 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
249 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
250 assert(default_vtable_indices() == NULL, "only create once");
251 set_default_vtable_indices(vtable_indices);
252 return vtable_indices;
253 }
254
255 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
256 _static_field_size(parser.static_field_size()),
257 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
258 _itable_len(parser.itable_size()),
259 _reference_type(parser.reference_type()),
260 _extra_flags(0) {
261 set_vtable_length(parser.vtable_size());
262 set_kind(kind);
263 set_access_flags(parser.access_flags());
264 set_is_anonymous(parser.is_anonymous());
265 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
266 false));
267 if (parser.has_value_fields()) {
268 set_has_value_fields();
269 }
270 _java_fields_count = parser.java_fields_count();
271
272 assert(NULL == _methods, "underlying memory not zeroed?");
273 assert(is_instance_klass(), "is layout incorrect?");
274 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
275 }
276
277 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
278 Array<Method*>* methods) {
279 if (methods != NULL && methods != Universe::the_empty_method_array() &&
280 !methods->is_shared()) {
281 for (int i = 0; i < methods->length(); i++) {
282 Method* method = methods->at(i);
283 if (method == NULL) continue; // maybe null if error processing
284 // Only want to delete methods that are not executing for RedefineClasses.
285 // The previous version will point to them so they're not totally dangling
286 assert (!method->on_stack(), "shouldn't be called with methods on stack");
287 MetadataFactory::free_metadata(loader_data, method);
288 }
289 MetadataFactory::free_array<Method*>(loader_data, methods);
290 }
291 }
292
293 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
294 const Klass* super_klass,
295 Array<Klass*>* local_interfaces,
296 Array<Klass*>* transitive_interfaces) {
297 // Only deallocate transitive interfaces if not empty, same as super class
298 // or same as local interfaces. See code in parseClassFile.
299 Array<Klass*>* ti = transitive_interfaces;
300 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
301 // check that the interfaces don't come from super class
302 Array<Klass*>* sti = (super_klass == NULL) ? NULL :
303 InstanceKlass::cast(super_klass)->transitive_interfaces();
304 if (ti != sti && ti != NULL && !ti->is_shared()) {
305 MetadataFactory::free_array<Klass*>(loader_data, ti);
306 }
307 }
308
309 // local interfaces can be empty
310 if (local_interfaces != Universe::the_empty_klass_array() &&
311 local_interfaces != NULL && !local_interfaces->is_shared()) {
312 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
313 }
314 }
315
316 // This function deallocates the metadata and C heap pointers that the
317 // InstanceKlass points to.
318 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
319
320 // Orphan the mirror first, CMS thinks it's still live.
321 if (java_mirror() != NULL) {
322 java_lang_Class::set_klass(java_mirror(), NULL);
323 }
324
325 // Need to take this class off the class loader data list.
326 loader_data->remove_class(this);
327
328 // The array_klass for this class is created later, after error handling.
329 // For class redefinition, we keep the original class so this scratch class
330 // doesn't have an array class. Either way, assert that there is nothing
331 // to deallocate.
332 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
333
334 // Release C heap allocated data that this might point to, which includes
335 // reference counting symbol names.
336 release_C_heap_structures();
337
338 deallocate_methods(loader_data, methods());
339 set_methods(NULL);
340
341 if (method_ordering() != NULL &&
342 method_ordering() != Universe::the_empty_int_array() &&
343 !method_ordering()->is_shared()) {
344 MetadataFactory::free_array<int>(loader_data, method_ordering());
345 }
346 set_method_ordering(NULL);
347
348 // default methods can be empty
349 if (default_methods() != NULL &&
350 default_methods() != Universe::the_empty_method_array() &&
351 !default_methods()->is_shared()) {
352 MetadataFactory::free_array<Method*>(loader_data, default_methods());
353 }
354 // Do NOT deallocate the default methods, they are owned by superinterfaces.
355 set_default_methods(NULL);
356
357 // default methods vtable indices can be empty
358 if (default_vtable_indices() != NULL &&
359 !default_vtable_indices()->is_shared()) {
360 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
361 }
362 set_default_vtable_indices(NULL);
363
364
365 // This array is in Klass, but remove it with the InstanceKlass since
366 // this place would be the only caller and it can share memory with transitive
367 // interfaces.
368 if (secondary_supers() != NULL &&
369 secondary_supers() != Universe::the_empty_klass_array() &&
370 secondary_supers() != transitive_interfaces() &&
371 !secondary_supers()->is_shared()) {
372 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
373 }
374 set_secondary_supers(NULL);
375
376 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
377 set_transitive_interfaces(NULL);
378 set_local_interfaces(NULL);
379
380 if (fields() != NULL && !fields()->is_shared()) {
381 MetadataFactory::free_array<jushort>(loader_data, fields());
382 }
383 set_fields(NULL, 0);
384
385 // If a method from a redefined class is using this constant pool, don't
386 // delete it, yet. The new class's previous version will point to this.
387 if (constants() != NULL) {
388 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
389 if (!constants()->is_shared()) {
390 MetadataFactory::free_metadata(loader_data, constants());
391 }
392 // Delete any cached resolution errors for the constant pool
393 SystemDictionary::delete_resolution_error(constants());
394
395 set_constants(NULL);
396 }
397
398 if (inner_classes() != NULL &&
399 inner_classes() != Universe::the_empty_short_array() &&
400 !inner_classes()->is_shared()) {
401 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
402 }
403 set_inner_classes(NULL);
404
405 // We should deallocate the Annotations instance if it's not in shared spaces.
406 if (annotations() != NULL && !annotations()->is_shared()) {
407 MetadataFactory::free_metadata(loader_data, annotations());
408 }
409 set_annotations(NULL);
410 }
411
412 bool InstanceKlass::should_be_initialized() const {
413 return !is_initialized();
414 }
415
416 klassItable InstanceKlass::itable() const {
417 return klassItable(const_cast<InstanceKlass*>(this));
418 }
419
420 void InstanceKlass::eager_initialize(Thread *thread) {
421 if (!EagerInitialization) return;
422
423 if (this->is_not_initialized()) {
424 // abort if the the class has a class initializer
425 if (this->class_initializer() != NULL) return;
426
427 // abort if it is java.lang.Object (initialization is handled in genesis)
428 Klass* super_klass = super();
429 if (super_klass == NULL) return;
430
431 // abort if the super class should be initialized
432 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
433
434 // call body to expose the this pointer
435 eager_initialize_impl();
436 }
437 }
438
439 // JVMTI spec thinks there are signers and protection domain in the
440 // instanceKlass. These accessors pretend these fields are there.
441 // The hprof specification also thinks these fields are in InstanceKlass.
442 oop InstanceKlass::protection_domain() const {
443 // return the protection_domain from the mirror
444 return java_lang_Class::protection_domain(java_mirror());
445 }
446
447 // To remove these from requires an incompatible change and CCC request.
448 objArrayOop InstanceKlass::signers() const {
449 // return the signers from the mirror
450 return java_lang_Class::signers(java_mirror());
451 }
452
453 oop InstanceKlass::init_lock() const {
454 // return the init lock from the mirror
455 oop lock = java_lang_Class::init_lock(java_mirror());
456 // Prevent reordering with any access of initialization state
457 OrderAccess::loadload();
458 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
459 "only fully initialized state can have a null lock");
460 return lock;
461 }
462
463 // Set the initialization lock to null so the object can be GC'ed. Any racing
464 // threads to get this lock will see a null lock and will not lock.
465 // That's okay because they all check for initialized state after getting
466 // the lock and return.
467 void InstanceKlass::fence_and_clear_init_lock() {
468 // make sure previous stores are all done, notably the init_state.
469 OrderAccess::storestore();
470 java_lang_Class::set_init_lock(java_mirror(), NULL);
471 assert(!is_not_initialized(), "class must be initialized now");
472 }
473
474 void InstanceKlass::eager_initialize_impl() {
475 EXCEPTION_MARK;
476 HandleMark hm(THREAD);
477 Handle h_init_lock(THREAD, init_lock());
478 ObjectLocker ol(h_init_lock, THREAD, init_lock() != NULL);
479
480 // abort if someone beat us to the initialization
481 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
482
483 ClassState old_state = init_state();
484 link_class_impl(true, THREAD);
485 if (HAS_PENDING_EXCEPTION) {
486 CLEAR_PENDING_EXCEPTION;
487 // Abort if linking the class throws an exception.
488
489 // Use a test to avoid redundantly resetting the state if there's
490 // no change. Set_init_state() asserts that state changes make
491 // progress, whereas here we might just be spinning in place.
492 if (old_state != _init_state)
493 set_init_state(old_state);
494 } else {
495 // linking successfull, mark class as initialized
496 set_init_state(fully_initialized);
497 fence_and_clear_init_lock();
498 // trace
499 if (log_is_enabled(Info, class, init)) {
500 ResourceMark rm(THREAD);
501 log_info(class, init)("[Initialized %s without side effects]", external_name());
502 }
503 }
504 }
505
506
507 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
508 // process. The step comments refers to the procedure described in that section.
509 // Note: implementation moved to static method to expose the this pointer.
510 void InstanceKlass::initialize(TRAPS) {
511 if (this->should_be_initialized()) {
512 initialize_impl(CHECK);
513 // Note: at this point the class may be initialized
514 // OR it may be in the state of being initialized
515 // in case of recursive initialization!
516 } else {
517 assert(is_initialized(), "sanity check");
518 }
519 }
520
521
522 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) {
523 // 1) Verify the bytecodes
524 Verifier::Mode mode =
525 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
526 return Verifier::verify(this, mode, should_verify_class(), THREAD);
527 }
528
529
530 // Used exclusively by the shared spaces dump mechanism to prevent
531 // classes mapped into the shared regions in new VMs from appearing linked.
532
533 void InstanceKlass::unlink_class() {
534 assert(is_linked(), "must be linked");
535 _init_state = loaded;
536 }
537
538 void InstanceKlass::link_class(TRAPS) {
539 assert(is_loaded(), "must be loaded");
540 if (!is_linked()) {
541 link_class_impl(true, CHECK);
542 }
543 }
544
545 // Called to verify that a class can link during initialization, without
546 // throwing a VerifyError.
547 bool InstanceKlass::link_class_or_fail(TRAPS) {
548 assert(is_loaded(), "must be loaded");
549 if (!is_linked()) {
550 link_class_impl(false, CHECK_false);
551 }
552 return is_linked();
553 }
554
555 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) {
556 if (DumpSharedSpaces && is_in_error_state()) {
557 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
558 // the class has failed verification. Throwing the NoClassDefFoundError here is just
559 // a convenient way to stop repeat attempts to verify the same (bad) class.
560 //
561 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
562 // if we are executing Java code. This is not a problem for CDS dumping phase since
563 // it doesn't execute any Java code.
564 ResourceMark rm(THREAD);
565 Exceptions::fthrow(THREAD_AND_LOCATION,
566 vmSymbols::java_lang_NoClassDefFoundError(),
567 "Class %s, or one of its supertypes, failed class initialization",
568 external_name());
569 return false;
570 }
571 // return if already verified
572 if (is_linked()) {
573 return true;
574 }
575
576 // Timing
577 // timer handles recursion
578 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
579 JavaThread* jt = (JavaThread*)THREAD;
580
581 // link super class before linking this class
582 Klass* super_klass = super();
583 if (super_klass != NULL) {
584 if (super_klass->is_interface()) { // check if super class is an interface
585 ResourceMark rm(THREAD);
586 Exceptions::fthrow(
587 THREAD_AND_LOCATION,
588 vmSymbols::java_lang_IncompatibleClassChangeError(),
589 "class %s has interface %s as super class",
590 external_name(),
591 super_klass->external_name()
592 );
593 return false;
594 }
595
596 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
597 ik_super->link_class_impl(throw_verifyerror, CHECK_false);
598 }
599
600 // link all interfaces implemented by this class before linking this class
601 Array<Klass*>* interfaces = local_interfaces();
602 int num_interfaces = interfaces->length();
603 for (int index = 0; index < num_interfaces; index++) {
604 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
605 interk->link_class_impl(throw_verifyerror, CHECK_false);
606 }
607
608 // If a value type is referenced by a class (either as a field type or a
609 // method argument or return type) this value type must be loaded during
610 // the linking of this class because size and properties of the value type
611 // must be known in order to be able to perform value type optimizations
612
613 // Note: circular dependencies between value types are not handled yet
614
615 // Note: one case is not handled yet: arrays of value types => FixMe
616
617 // Note: the current implementation is not optimized because the search for
618 // value types is performed on all classes. It would be more efficient to
619 // detect value types during verification and 'tag' the classes for which
620 // value type loading is required. However, this optimization won't be
621 // applicable to classes that are not verified
622
623 // First step: fields
624 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
625 ResourceMark rm(THREAD);
626 if (fs.field_descriptor().field_type() == T_VALUETYPE) {
627 Symbol* signature = fs.field_descriptor().signature();
628 // Get current loader and protection domain first.
629 oop loader = class_loader();
630 oop prot_domain = protection_domain();
631 Klass* klass = SystemDictionary::resolve_or_fail(signature,
632 Handle(THREAD, loader), Handle(THREAD, prot_domain), true,
633 THREAD);
634 if (klass == NULL) {
635 THROW_(vmSymbols::java_lang_LinkageError(), false);
636 }
637 }
638 }
639
640 // Second step: methods arguments and return types
641 // for (int i = 0; i < this_k->constants()->length(); i++) {
642 // if (this_k->constants()->tag_at(i).is_method()) {
643 // Symbol* signature = this_k->constants()->signature_ref_at(i);
644 // ResourceMark rm(THREAD);
645 // for (SignatureStream ss(signature); !ss.is_done(); ss.next()) {
646 // if (ss.type() == T_VALUETYPE) {
647 // Symbol* sig = ss.as_symbol(THREAD);
648 // // Get current loader and protection domain first.
649 // oop loader = this_k->class_loader();
650 // oop protection_domain = this_k->protection_domain();
651 //
652 // bool ok = SystemDictionary::resolve_or_fail(sig,
653 // Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
654 // THREAD);
655 // if (!ok) {
656 // THROW_(vmSymbols::java_lang_LinkageError(), false);
657 // }
658 // }
659 // }
660 // }
661 // }
662
663 // in case the class is linked in the process of linking its superclasses
664 if (is_linked()) {
665 return true;
666 }
667
668 // trace only the link time for this klass that includes
669 // the verification time
670 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
671 ClassLoader::perf_class_link_selftime(),
672 ClassLoader::perf_classes_linked(),
673 jt->get_thread_stat()->perf_recursion_counts_addr(),
674 jt->get_thread_stat()->perf_timers_addr(),
675 PerfClassTraceTime::CLASS_LINK);
676
677 // verification & rewriting
678 {
679 HandleMark hm(THREAD);
680 Handle h_init_lock(THREAD, init_lock());
681 ObjectLocker ol(h_init_lock, THREAD, init_lock() != NULL);
682 // rewritten will have been set if loader constraint error found
683 // on an earlier link attempt
684 // don't verify or rewrite if already rewritten
685 //
686
687 if (!is_linked()) {
688 // The VCC must be linked before the DVT
689 if (get_vcc_klass() != NULL) {
690 InstanceKlass::cast(get_vcc_klass())->link_class(CHECK_false);
691 }
692
693 if (!is_rewritten()) {
694 {
695 bool verify_ok = verify_code(throw_verifyerror, THREAD);
696 if (!verify_ok) {
697 return false;
698 }
699 }
700
701 // Just in case a side-effect of verify linked this class already
702 // (which can sometimes happen since the verifier loads classes
703 // using custom class loaders, which are free to initialize things)
704 if (is_linked()) {
705 return true;
706 }
707
708 // also sets rewritten
709 rewrite_class(CHECK_false);
710 } else if (is_shared()) {
711 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
712 }
713
714 // relocate jsrs and link methods after they are all rewritten
715 link_methods(CHECK_false);
716
717 // Initialize the vtable and interface table after
718 // methods have been rewritten since rewrite may
719 // fabricate new Method*s.
720 // also does loader constraint checking
721 //
722 // initialize_vtable and initialize_itable need to be rerun for
723 // a shared class if the class is not loaded by the NULL classloader.
724 ClassLoaderData * loader_data = class_loader_data();
725 if (!(is_shared() &&
726 loader_data->is_the_null_class_loader_data())) {
727 ResourceMark rm(THREAD);
728 vtable().initialize_vtable(true, CHECK_false);
729 itable().initialize_itable(true, CHECK_false);
730 }
731 #ifdef ASSERT
732 else {
733 vtable().verify(tty, true);
734 // In case itable verification is ever added.
735 // itable().verify(tty, true);
736 }
737 #endif
738
739 set_init_state(linked);
740 if (JvmtiExport::should_post_class_prepare()) {
741 Thread *thread = THREAD;
742 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
743 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
744 }
745 }
746 }
747 return true;
748 }
749
750
751 // Rewrite the byte codes of all of the methods of a class.
752 // The rewriter must be called exactly once. Rewriting must happen after
753 // verification but before the first method of the class is executed.
754 void InstanceKlass::rewrite_class(TRAPS) {
755 assert(is_loaded(), "must be loaded");
756 if (is_rewritten()) {
757 assert(is_shared(), "rewriting an unshared class?");
758 return;
759 }
760 Rewriter::rewrite(this, CHECK);
761 set_rewritten();
762 }
763
764 // Now relocate and link method entry points after class is rewritten.
765 // This is outside is_rewritten flag. In case of an exception, it can be
766 // executed more than once.
767 void InstanceKlass::link_methods(TRAPS) {
768 int len = methods()->length();
769 for (int i = len-1; i >= 0; i--) {
770 methodHandle m(THREAD, methods()->at(i));
771
772 // Set up method entry points for compiler and interpreter .
773 m->link_method(m, CHECK);
774 }
775 }
776
777 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
778 void InstanceKlass::initialize_super_interfaces(TRAPS) {
779 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
780 for (int i = 0; i < local_interfaces()->length(); ++i) {
781 Klass* iface = local_interfaces()->at(i);
782 InstanceKlass* ik = InstanceKlass::cast(iface);
783
784 // Initialization is depth first search ie. we start with top of the inheritance tree
785 // has_nonstatic_concrete_methods drives searching superinterfaces since it
786 // means has_nonstatic_concrete_methods in its superinterface hierarchy
787 if (ik->has_nonstatic_concrete_methods()) {
788 ik->initialize_super_interfaces(CHECK);
789 }
790
791 // Only initialize() interfaces that "declare" concrete methods.
792 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
793 ik->initialize(CHECK);
794 }
795 }
796 }
797
798 void InstanceKlass::initialize_impl(TRAPS) {
799 HandleMark hm(THREAD);
800
801 // ensure outer VCC is initialized, possible some crafty code referred to VT 1st
802 if (get_vcc_klass() != NULL) {
803 get_vcc_klass()->initialize(CHECK);
804 }
805
806 // Make sure klass is linked (verified) before initialization
807 // A class could already be verified, since it has been reflected upon.
808 link_class(CHECK);
809
810 DTRACE_CLASSINIT_PROBE(required, -1);
811
812 bool wait = false;
813
814 // refer to the JVM book page 47 for description of steps
815 // Step 1
816 {
817 Handle h_init_lock(THREAD, init_lock());
818 ObjectLocker ol(h_init_lock, THREAD, init_lock() != NULL);
819
820 Thread *self = THREAD; // it's passed the current thread
821
822 // Step 2
823 // If we were to use wait() instead of waitInterruptibly() then
824 // we might end up throwing IE from link/symbol resolution sites
825 // that aren't expected to throw. This would wreak havoc. See 6320309.
826 while(is_being_initialized() && !is_reentrant_initialization(self)) {
827 wait = true;
828 ol.waitUninterruptibly(CHECK);
829 }
830
831 // Step 3
832 if (is_being_initialized() && is_reentrant_initialization(self)) {
833 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
834 return;
835 }
836
837 // Step 4
838 if (is_initialized()) {
839 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
840 return;
841 }
842
843 // Step 5
844 if (is_in_error_state()) {
845 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
846 ResourceMark rm(THREAD);
847 const char* desc = "Could not initialize class ";
848 const char* className = external_name();
849 size_t msglen = strlen(desc) + strlen(className) + 1;
850 char* message = NEW_RESOURCE_ARRAY(char, msglen);
851 if (NULL == message) {
852 // Out of memory: can't create detailed error message
853 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
854 } else {
855 jio_snprintf(message, msglen, "%s%s", desc, className);
856 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
857 }
858 }
859
860 // Step 6
861 set_init_state(being_initialized);
862 set_init_thread(self);
863 }
864
865 // Step 7
866 // Next, if C is a class rather than an interface, initialize it's super class and super
867 // interfaces.
868 if (!is_interface()) {
869 Klass* super_klass = super();
870 if (super_klass != NULL && super_klass->should_be_initialized()) {
871 super_klass->initialize(THREAD);
872 }
873 // If C implements any interface that declares a non-static, concrete method,
874 // the initialization of C triggers initialization of its super interfaces.
875 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
876 // having a superinterface that declares, non-static, concrete methods
877 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
878 initialize_super_interfaces(THREAD);
879 }
880
881 // If any exceptions, complete abruptly, throwing the same exception as above.
882 if (HAS_PENDING_EXCEPTION) {
883 Handle e(THREAD, PENDING_EXCEPTION);
884 CLEAR_PENDING_EXCEPTION;
885 {
886 EXCEPTION_MARK;
887 // Locks object, set state, and notify all waiting threads
888 set_initialization_state_and_notify(initialization_error, THREAD);
889 CLEAR_PENDING_EXCEPTION;
890 }
891 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
892 THROW_OOP(e());
893 }
894 }
895
896
897 // Look for aot compiled methods for this klass, including class initializer.
898 AOTLoader::load_for_klass(this, THREAD);
899
900 // Step 8
901 {
902 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
903 JavaThread* jt = (JavaThread*)THREAD;
904 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
905 // Timer includes any side effects of class initialization (resolution,
906 // etc), but not recursive entry into call_class_initializer().
907 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
908 ClassLoader::perf_class_init_selftime(),
909 ClassLoader::perf_classes_inited(),
910 jt->get_thread_stat()->perf_recursion_counts_addr(),
911 jt->get_thread_stat()->perf_timers_addr(),
912 PerfClassTraceTime::CLASS_CLINIT);
913 call_class_initializer(THREAD);
914 }
915
916 // Step 9
917 if (!HAS_PENDING_EXCEPTION) {
918 set_initialization_state_and_notify(fully_initialized, CHECK);
919 {
920 debug_only(vtable().verify(tty, true);)
921 }
922 }
923 else {
924 // Step 10 and 11
925 Handle e(THREAD, PENDING_EXCEPTION);
926 CLEAR_PENDING_EXCEPTION;
927 // JVMTI has already reported the pending exception
928 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
929 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
930 {
931 EXCEPTION_MARK;
932 set_initialization_state_and_notify(initialization_error, THREAD);
933 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
934 // JVMTI has already reported the pending exception
935 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
936 JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
937 }
938 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
939 if (e->is_a(SystemDictionary::Error_klass())) {
940 THROW_OOP(e());
941 } else {
942 JavaCallArguments args(e);
943 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
944 vmSymbols::throwable_void_signature(),
945 &args);
946 }
947 }
948 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
949 }
950
951
952 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
953 Handle h_init_lock(THREAD, init_lock());
954 if (init_lock() != NULL) {
955 ObjectLocker ol(h_init_lock, THREAD);
956 set_init_state(state);
957 fence_and_clear_init_lock();
958 ol.notify_all(CHECK);
959 } else {
960 assert(init_lock() != NULL, "The initialization state should never be set twice");
961 set_init_state(state);
962 }
963 }
964
965 // The embedded _implementor field can only record one implementor.
966 // When there are more than one implementors, the _implementor field
967 // is set to the interface Klass* itself. Following are the possible
968 // values for the _implementor field:
969 // NULL - no implementor
970 // implementor Klass* - one implementor
971 // self - more than one implementor
972 //
973 // The _implementor field only exists for interfaces.
974 void InstanceKlass::add_implementor(Klass* k) {
975 assert(Compile_lock->owned_by_self(), "");
976 assert(is_interface(), "not interface");
977 // Filter out my subinterfaces.
978 // (Note: Interfaces are never on the subklass list.)
979 if (InstanceKlass::cast(k)->is_interface()) return;
980
981 // Filter out subclasses whose supers already implement me.
982 // (Note: CHA must walk subclasses of direct implementors
983 // in order to locate indirect implementors.)
984 Klass* sk = k->super();
985 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
986 // We only need to check one immediate superclass, since the
987 // implements_interface query looks at transitive_interfaces.
988 // Any supers of the super have the same (or fewer) transitive_interfaces.
989 return;
990
991 Klass* ik = implementor();
992 if (ik == NULL) {
993 set_implementor(k);
994 } else if (ik != this) {
995 // There is already an implementor. Use itself as an indicator of
996 // more than one implementors.
997 set_implementor(this);
998 }
999
1000 // The implementor also implements the transitive_interfaces
1001 for (int index = 0; index < local_interfaces()->length(); index++) {
1002 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1003 }
1004 }
1005
1006 void InstanceKlass::init_implementor() {
1007 if (is_interface()) {
1008 set_implementor(NULL);
1009 }
1010 }
1011
1012
1013 void InstanceKlass::process_interfaces(Thread *thread) {
1014 // link this class into the implementors list of every interface it implements
1015 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1016 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1017 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1018 assert(interf->is_interface(), "expected interface");
1019 interf->add_implementor(this);
1020 }
1021 }
1022
1023 bool InstanceKlass::can_be_primary_super_slow() const {
1024 if (is_interface())
1025 return false;
1026 else
1027 return Klass::can_be_primary_super_slow();
1028 }
1029
1030 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1031 // The secondaries are the implemented interfaces.
1032 Array<Klass*>* interfaces = transitive_interfaces();
1033 int num_secondaries = num_extra_slots + interfaces->length();
1034 if (num_secondaries == 0) {
1035 // Must share this for correct bootstrapping!
1036 set_secondary_supers(Universe::the_empty_klass_array());
1037 return NULL;
1038 } else if (num_extra_slots == 0) {
1039 // The secondary super list is exactly the same as the transitive interfaces.
1040 // Redefine classes has to be careful not to delete this!
1041 set_secondary_supers(interfaces);
1042 return NULL;
1043 } else {
1044 // Copy transitive interfaces to a temporary growable array to be constructed
1045 // into the secondary super list with extra slots.
1046 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1047 for (int i = 0; i < interfaces->length(); i++) {
1048 secondaries->push(interfaces->at(i));
1049 }
1050 return secondaries;
1051 }
1052 }
1053
1054 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1055 if (k->is_interface()) {
1056 return implements_interface(k);
1057 } else {
1058 return Klass::compute_is_subtype_of(k);
1059 }
1060 }
1061
1062 bool InstanceKlass::implements_interface(Klass* k) const {
1063 if (this == k) return true;
1064 assert(k->is_interface(), "should be an interface class");
1065 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1066 if (transitive_interfaces()->at(i) == k) {
1067 return true;
1068 }
1069 }
1070 return false;
1071 }
1072
1073 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1074 // Verify direct super interface
1075 if (this == k) return true;
1076 assert(k->is_interface(), "should be an interface class");
1077 for (int i = 0; i < local_interfaces()->length(); i++) {
1078 if (local_interfaces()->at(i) == k) {
1079 return true;
1080 }
1081 }
1082 return false;
1083 }
1084
1085 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1086 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1087 if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1088 report_java_out_of_memory("Requested array size exceeds VM limit");
1089 JvmtiExport::post_array_size_exhausted();
1090 THROW_OOP_0(Universe::out_of_memory_error_array_size());
1091 }
1092 int size = objArrayOopDesc::object_size(length);
1093 Klass* ak = array_klass(n, CHECK_NULL);
1094 objArrayOop o =
1095 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
1096 return o;
1097 }
1098
1099 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1100 if (TraceFinalizerRegistration) {
1101 tty->print("Registered ");
1102 i->print_value_on(tty);
1103 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1104 }
1105 instanceHandle h_i(THREAD, i);
1106 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1107 JavaValue result(T_VOID);
1108 JavaCallArguments args(h_i);
1109 methodHandle mh (THREAD, Universe::finalizer_register_method());
1110 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1111 return h_i();
1112 }
1113
1114 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1115 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1116 int size = size_helper(); // Query before forming handle.
1117
1118 instanceOop i;
1119
1120 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1121 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1122 i = register_finalizer(i, CHECK_NULL);
1123 }
1124 return i;
1125 }
1126
1127 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1128 if (is_interface() || is_abstract()) {
1129 ResourceMark rm(THREAD);
1130 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1131 : vmSymbols::java_lang_InstantiationException(), external_name());
1132 }
1133 if (this == SystemDictionary::Class_klass()) {
1134 ResourceMark rm(THREAD);
1135 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1136 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1137 }
1138 }
1139
1140 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1141 // Need load-acquire for lock-free read
1142 if (array_klasses_acquire() == NULL) {
1143 if (or_null) return NULL;
1144
1145 ResourceMark rm;
1146 JavaThread *jt = (JavaThread *)THREAD;
1147 {
1148 // Atomic creation of array_klasses
1149 MutexLocker mc(Compile_lock, THREAD); // for vtables
1150 MutexLocker ma(MultiArray_lock, THREAD);
1151
1152 // Check if update has already taken place
1153 if (array_klasses() == NULL) {
1154 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1155 // use 'release' to pair with lock-free load
1156 release_set_array_klasses(k);
1157 }
1158 }
1159 }
1160 // _this will always be set at this point
1161 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1162 if (or_null) {
1163 return oak->array_klass_or_null(n);
1164 }
1165 return oak->array_klass(n, THREAD);
1166 }
1167
1168 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1169 return array_klass_impl(or_null, 1, THREAD);
1170 }
1171
1172 static int call_class_initializer_counter = 0; // for debugging
1173
1174 Method* InstanceKlass::class_initializer() const {
1175 Method* clinit = find_method(
1176 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1177 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1178 return clinit;
1179 }
1180 return NULL;
1181 }
1182
1183 void InstanceKlass::call_class_initializer(TRAPS) {
1184 if (ReplayCompiles &&
1185 (ReplaySuppressInitializers == 1 ||
1186 ReplaySuppressInitializers >= 2 && class_loader() != NULL)) {
1187 // Hide the existence of the initializer for the purpose of replaying the compile
1188 return;
1189 }
1190
1191 methodHandle h_method(THREAD, class_initializer());
1192 assert(!is_initialized(), "we cannot initialize twice");
1193 if (log_is_enabled(Info, class, init)) {
1194 ResourceMark rm;
1195 outputStream* log = Log(class, init)::info_stream();
1196 log->print("%d Initializing ", call_class_initializer_counter++);
1197 name()->print_value_on(log);
1198 log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1199 }
1200 if (h_method() != NULL) {
1201 JavaCallArguments args; // No arguments
1202 JavaValue result(T_VOID);
1203 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1204 }
1205 }
1206
1207
1208 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1209 InterpreterOopMap* entry_for) {
1210 // Lazily create the _oop_map_cache at first request
1211 // Lock-free access requires load_ptr_acquire.
1212 OopMapCache* oop_map_cache =
1213 static_cast<OopMapCache*>(OrderAccess::load_ptr_acquire(&_oop_map_cache));
1214 if (oop_map_cache == NULL) {
1215 MutexLockerEx x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag);
1216 // Check if _oop_map_cache was allocated while we were waiting for this lock
1217 if ((oop_map_cache = _oop_map_cache) == NULL) {
1218 oop_map_cache = new OopMapCache();
1219 // Ensure _oop_map_cache is stable, since it is examined without a lock
1220 OrderAccess::release_store_ptr(&_oop_map_cache, oop_map_cache);
1221 }
1222 }
1223 // _oop_map_cache is constant after init; lookup below does its own locking.
1224 oop_map_cache->lookup(method, bci, entry_for);
1225 }
1226
1227
1228 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1229 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1230 Symbol* f_name = fs.name();
1231 Symbol* f_sig = fs.signature();
1232 if (f_name == name && f_sig == sig) {
1233 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1234 return true;
1235 }
1236 }
1237 return false;
1238 }
1239
1240
1241 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1242 const int n = local_interfaces()->length();
1243 for (int i = 0; i < n; i++) {
1244 Klass* intf1 = local_interfaces()->at(i);
1245 assert(intf1->is_interface(), "just checking type");
1246 // search for field in current interface
1247 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1248 assert(fd->is_static(), "interface field must be static");
1249 return intf1;
1250 }
1251 // search for field in direct superinterfaces
1252 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1253 if (intf2 != NULL) return intf2;
1254 }
1255 // otherwise field lookup fails
1256 return NULL;
1257 }
1258
1259
1260 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1261 // search order according to newest JVM spec (5.4.3.2, p.167).
1262 // 1) search for field in current klass
1263 if (find_local_field(name, sig, fd)) {
1264 return const_cast<InstanceKlass*>(this);
1265 }
1266 // 2) search for field recursively in direct superinterfaces
1267 { Klass* intf = find_interface_field(name, sig, fd);
1268 if (intf != NULL) return intf;
1269 }
1270 // 3) apply field lookup recursively if superclass exists
1271 { Klass* supr = super();
1272 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1273 }
1274 // 4) otherwise field lookup fails
1275 return NULL;
1276 }
1277
1278
1279 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1280 // search order according to newest JVM spec (5.4.3.2, p.167).
1281 // 1) search for field in current klass
1282 if (find_local_field(name, sig, fd)) {
1283 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1284 }
1285 // 2) search for field recursively in direct superinterfaces
1286 if (is_static) {
1287 Klass* intf = find_interface_field(name, sig, fd);
1288 if (intf != NULL) return intf;
1289 }
1290 // 3) apply field lookup recursively if superclass exists
1291 { Klass* supr = super();
1292 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1293 }
1294 // 4) otherwise field lookup fails
1295 return NULL;
1296 }
1297
1298
1299 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1300 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1301 if (fs.offset() == offset) {
1302 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1303 if (fd->is_static() == is_static) return true;
1304 }
1305 }
1306 return false;
1307 }
1308
1309
1310 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1311 Klass* klass = const_cast<InstanceKlass*>(this);
1312 while (klass != NULL) {
1313 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1314 return true;
1315 }
1316 klass = klass->super();
1317 }
1318 return false;
1319 }
1320
1321
1322 void InstanceKlass::methods_do(void f(Method* method)) {
1323 // Methods aren't stable until they are loaded. This can be read outside
1324 // a lock through the ClassLoaderData for profiling
1325 if (!is_loaded()) {
1326 return;
1327 }
1328
1329 int len = methods()->length();
1330 for (int index = 0; index < len; index++) {
1331 Method* m = methods()->at(index);
1332 assert(m->is_method(), "must be method");
1333 f(m);
1334 }
1335 }
1336
1337
1338 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1339 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1340 if (fs.access_flags().is_static()) {
1341 fieldDescriptor& fd = fs.field_descriptor();
1342 cl->do_field(&fd);
1343 }
1344 }
1345 }
1346
1347
1348 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1349 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1350 if (fs.access_flags().is_static()) {
1351 fieldDescriptor& fd = fs.field_descriptor();
1352 f(&fd, mirror, CHECK);
1353 }
1354 }
1355 }
1356
1357
1358 static int compare_fields_by_offset(int* a, int* b) {
1359 return a[0] - b[0];
1360 }
1361
1362 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1363 InstanceKlass* super = superklass();
1364 if (super != NULL) {
1365 super->do_nonstatic_fields(cl);
1366 }
1367 fieldDescriptor fd;
1368 int length = java_fields_count();
1369 // In DebugInfo nonstatic fields are sorted by offset.
1370 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1371 int j = 0;
1372 for (int i = 0; i < length; i += 1) {
1373 fd.reinitialize(this, i);
1374 if (!fd.is_static()) {
1375 fields_sorted[j + 0] = fd.offset();
1376 fields_sorted[j + 1] = i;
1377 j += 2;
1378 }
1379 }
1380 if (j > 0) {
1381 length = j;
1382 // _sort_Fn is defined in growableArray.hpp.
1383 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1384 for (int i = 0; i < length; i += 2) {
1385 fd.reinitialize(this, fields_sorted[i + 1]);
1386 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1387 cl->do_field(&fd);
1388 }
1389 }
1390 FREE_C_HEAP_ARRAY(int, fields_sorted);
1391 }
1392
1393
1394 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1395 if (array_klasses() != NULL)
1396 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1397 }
1398
1399 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1400 if (array_klasses() != NULL)
1401 ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1402 }
1403
1404 #ifdef ASSERT
1405 static int linear_search(const Array<Method*>* methods,
1406 const Symbol* name,
1407 const Symbol* signature) {
1408 const int len = methods->length();
1409 for (int index = 0; index < len; index++) {
1410 const Method* const m = methods->at(index);
1411 assert(m->is_method(), "must be method");
1412 if (m->signature() == signature && m->name() == name) {
1413 return index;
1414 }
1415 }
1416 return -1;
1417 }
1418 #endif
1419
1420 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1421 int len = methods->length();
1422 // methods are sorted, so do binary search
1423 int l = 0;
1424 int h = len - 1;
1425 while (l <= h) {
1426 int mid = (l + h) >> 1;
1427 Method* m = methods->at(mid);
1428 assert(m->is_method(), "must be method");
1429 int res = m->name()->fast_compare(name);
1430 if (res == 0) {
1431 return mid;
1432 } else if (res < 0) {
1433 l = mid + 1;
1434 } else {
1435 h = mid - 1;
1436 }
1437 }
1438 return -1;
1439 }
1440
1441 // find_method looks up the name/signature in the local methods array
1442 Method* InstanceKlass::find_method(const Symbol* name,
1443 const Symbol* signature) const {
1444 return find_method_impl(name, signature, find_overpass, find_static, find_private);
1445 }
1446
1447 Method* InstanceKlass::find_method_impl(const Symbol* name,
1448 const Symbol* signature,
1449 OverpassLookupMode overpass_mode,
1450 StaticLookupMode static_mode,
1451 PrivateLookupMode private_mode) const {
1452 return InstanceKlass::find_method_impl(methods(),
1453 name,
1454 signature,
1455 overpass_mode,
1456 static_mode,
1457 private_mode);
1458 }
1459
1460 // find_instance_method looks up the name/signature in the local methods array
1461 // and skips over static methods
1462 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1463 const Symbol* name,
1464 const Symbol* signature) {
1465 Method* const meth = InstanceKlass::find_method_impl(methods,
1466 name,
1467 signature,
1468 find_overpass,
1469 skip_static,
1470 find_private);
1471 assert(((meth == NULL) || !meth->is_static()),
1472 "find_instance_method should have skipped statics");
1473 return meth;
1474 }
1475
1476 // find_instance_method looks up the name/signature in the local methods array
1477 // and skips over static methods
1478 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1479 return InstanceKlass::find_instance_method(methods(), name, signature);
1480 }
1481
1482 // Find looks up the name/signature in the local methods array
1483 // and filters on the overpass, static and private flags
1484 // This returns the first one found
1485 // note that the local methods array can have up to one overpass, one static
1486 // and one instance (private or not) with the same name/signature
1487 Method* InstanceKlass::find_local_method(const Symbol* name,
1488 const Symbol* signature,
1489 OverpassLookupMode overpass_mode,
1490 StaticLookupMode static_mode,
1491 PrivateLookupMode private_mode) const {
1492 return InstanceKlass::find_method_impl(methods(),
1493 name,
1494 signature,
1495 overpass_mode,
1496 static_mode,
1497 private_mode);
1498 }
1499
1500 // Find looks up the name/signature in the local methods array
1501 // and filters on the overpass, static and private flags
1502 // This returns the first one found
1503 // note that the local methods array can have up to one overpass, one static
1504 // and one instance (private or not) with the same name/signature
1505 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1506 const Symbol* name,
1507 const Symbol* signature,
1508 OverpassLookupMode overpass_mode,
1509 StaticLookupMode static_mode,
1510 PrivateLookupMode private_mode) {
1511 return InstanceKlass::find_method_impl(methods,
1512 name,
1513 signature,
1514 overpass_mode,
1515 static_mode,
1516 private_mode);
1517 }
1518
1519 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1520 const Symbol* name,
1521 const Symbol* signature) {
1522 return InstanceKlass::find_method_impl(methods,
1523 name,
1524 signature,
1525 find_overpass,
1526 find_static,
1527 find_private);
1528 }
1529
1530 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1531 const Symbol* name,
1532 const Symbol* signature,
1533 OverpassLookupMode overpass_mode,
1534 StaticLookupMode static_mode,
1535 PrivateLookupMode private_mode) {
1536 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1537 return hit >= 0 ? methods->at(hit): NULL;
1538 }
1539
1540 // true if method matches signature and conforms to skipping_X conditions.
1541 static bool method_matches(const Method* m,
1542 const Symbol* signature,
1543 bool skipping_overpass,
1544 bool skipping_static,
1545 bool skipping_private) {
1546 return ((m->signature() == signature) &&
1547 (!skipping_overpass || !m->is_overpass()) &&
1548 (!skipping_static || !m->is_static()) &&
1549 (!skipping_private || !m->is_private()));
1550 }
1551
1552 // Used directly for default_methods to find the index into the
1553 // default_vtable_indices, and indirectly by find_method
1554 // find_method_index looks in the local methods array to return the index
1555 // of the matching name/signature. If, overpass methods are being ignored,
1556 // the search continues to find a potential non-overpass match. This capability
1557 // is important during method resolution to prefer a static method, for example,
1558 // over an overpass method.
1559 // There is the possibility in any _method's array to have the same name/signature
1560 // for a static method, an overpass method and a local instance method
1561 // To correctly catch a given method, the search criteria may need
1562 // to explicitly skip the other two. For local instance methods, it
1563 // is often necessary to skip private methods
1564 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1565 const Symbol* name,
1566 const Symbol* signature,
1567 OverpassLookupMode overpass_mode,
1568 StaticLookupMode static_mode,
1569 PrivateLookupMode private_mode) {
1570 const bool skipping_overpass = (overpass_mode == skip_overpass);
1571 const bool skipping_static = (static_mode == skip_static);
1572 const bool skipping_private = (private_mode == skip_private);
1573 const int hit = binary_search(methods, name);
1574 if (hit != -1) {
1575 const Method* const m = methods->at(hit);
1576
1577 // Do linear search to find matching signature. First, quick check
1578 // for common case, ignoring overpasses if requested.
1579 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1580 return hit;
1581 }
1582
1583 // search downwards through overloaded methods
1584 int i;
1585 for (i = hit - 1; i >= 0; --i) {
1586 const Method* const m = methods->at(i);
1587 assert(m->is_method(), "must be method");
1588 if (m->name() != name) {
1589 break;
1590 }
1591 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1592 return i;
1593 }
1594 }
1595 // search upwards
1596 for (i = hit + 1; i < methods->length(); ++i) {
1597 const Method* const m = methods->at(i);
1598 assert(m->is_method(), "must be method");
1599 if (m->name() != name) {
1600 break;
1601 }
1602 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1603 return i;
1604 }
1605 }
1606 // not found
1607 #ifdef ASSERT
1608 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1609 linear_search(methods, name, signature);
1610 assert(-1 == index, "binary search should have found entry %d", index);
1611 #endif
1612 }
1613 return -1;
1614 }
1615
1616 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1617 return find_method_by_name(methods(), name, end);
1618 }
1619
1620 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1621 const Symbol* name,
1622 int* end_ptr) {
1623 assert(end_ptr != NULL, "just checking");
1624 int start = binary_search(methods, name);
1625 int end = start + 1;
1626 if (start != -1) {
1627 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1628 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1629 *end_ptr = end;
1630 return start;
1631 }
1632 return -1;
1633 }
1634
1635 // uncached_lookup_method searches both the local class methods array and all
1636 // superclasses methods arrays, skipping any overpass methods in superclasses.
1637 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1638 const Symbol* signature,
1639 OverpassLookupMode overpass_mode) const {
1640 OverpassLookupMode overpass_local_mode = overpass_mode;
1641 const Klass* klass = this;
1642 while (klass != NULL) {
1643 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1644 signature,
1645 overpass_local_mode,
1646 find_static,
1647 find_private);
1648 if (method != NULL) {
1649 return method;
1650 }
1651 klass = klass->super();
1652 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses
1653 }
1654 return NULL;
1655 }
1656
1657 #ifdef ASSERT
1658 // search through class hierarchy and return true if this class or
1659 // one of the superclasses was redefined
1660 bool InstanceKlass::has_redefined_this_or_super() const {
1661 const Klass* klass = this;
1662 while (klass != NULL) {
1663 if (InstanceKlass::cast(klass)->has_been_redefined()) {
1664 return true;
1665 }
1666 klass = klass->super();
1667 }
1668 return false;
1669 }
1670 #endif
1671
1672 // lookup a method in the default methods list then in all transitive interfaces
1673 // Do NOT return private or static methods
1674 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1675 Symbol* signature) const {
1676 Method* m = NULL;
1677 if (default_methods() != NULL) {
1678 m = find_method(default_methods(), name, signature);
1679 }
1680 // Look up interfaces
1681 if (m == NULL) {
1682 m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1683 }
1684 return m;
1685 }
1686
1687 // lookup a method in all the interfaces that this class implements
1688 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1689 // They should only be found in the initial InterfaceMethodRef
1690 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1691 Symbol* signature,
1692 DefaultsLookupMode defaults_mode) const {
1693 Array<Klass*>* all_ifs = transitive_interfaces();
1694 int num_ifs = all_ifs->length();
1695 InstanceKlass *ik = NULL;
1696 for (int i = 0; i < num_ifs; i++) {
1697 ik = InstanceKlass::cast(all_ifs->at(i));
1698 Method* m = ik->lookup_method(name, signature);
1699 if (m != NULL && m->is_public() && !m->is_static() &&
1700 ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1701 return m;
1702 }
1703 }
1704 return NULL;
1705 }
1706
1707 /* jni_id_for_impl for jfieldIds only */
1708 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1709 MutexLocker ml(JfieldIdCreation_lock);
1710 // Retry lookup after we got the lock
1711 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1712 if (probe == NULL) {
1713 // Slow case, allocate new static field identifier
1714 probe = new JNIid(this, offset, jni_ids());
1715 set_jni_ids(probe);
1716 }
1717 return probe;
1718 }
1719
1720
1721 /* jni_id_for for jfieldIds only */
1722 JNIid* InstanceKlass::jni_id_for(int offset) {
1723 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1724 if (probe == NULL) {
1725 probe = jni_id_for_impl(offset);
1726 }
1727 return probe;
1728 }
1729
1730 u2 InstanceKlass::enclosing_method_data(int offset) const {
1731 const Array<jushort>* const inner_class_list = inner_classes();
1732 if (inner_class_list == NULL) {
1733 return 0;
1734 }
1735 const int length = inner_class_list->length();
1736 if (length % inner_class_next_offset == 0) {
1737 return 0;
1738 }
1739 const int index = length - enclosing_method_attribute_size;
1740 assert(offset < enclosing_method_attribute_size, "invalid offset");
1741 return inner_class_list->at(index + offset);
1742 }
1743
1744 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1745 u2 method_index) {
1746 Array<jushort>* inner_class_list = inner_classes();
1747 assert (inner_class_list != NULL, "_inner_classes list is not set up");
1748 int length = inner_class_list->length();
1749 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1750 int index = length - enclosing_method_attribute_size;
1751 inner_class_list->at_put(
1752 index + enclosing_method_class_index_offset, class_index);
1753 inner_class_list->at_put(
1754 index + enclosing_method_method_index_offset, method_index);
1755 }
1756 }
1757
1758 // Lookup or create a jmethodID.
1759 // This code is called by the VMThread and JavaThreads so the
1760 // locking has to be done very carefully to avoid deadlocks
1761 // and/or other cache consistency problems.
1762 //
1763 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1764 size_t idnum = (size_t)method_h->method_idnum();
1765 jmethodID* jmeths = methods_jmethod_ids_acquire();
1766 size_t length = 0;
1767 jmethodID id = NULL;
1768
1769 // We use a double-check locking idiom here because this cache is
1770 // performance sensitive. In the normal system, this cache only
1771 // transitions from NULL to non-NULL which is safe because we use
1772 // release_set_methods_jmethod_ids() to advertise the new cache.
1773 // A partially constructed cache should never be seen by a racing
1774 // thread. We also use release_store_ptr() to save a new jmethodID
1775 // in the cache so a partially constructed jmethodID should never be
1776 // seen either. Cache reads of existing jmethodIDs proceed without a
1777 // lock, but cache writes of a new jmethodID requires uniqueness and
1778 // creation of the cache itself requires no leaks so a lock is
1779 // generally acquired in those two cases.
1780 //
1781 // If the RedefineClasses() API has been used, then this cache can
1782 // grow and we'll have transitions from non-NULL to bigger non-NULL.
1783 // Cache creation requires no leaks and we require safety between all
1784 // cache accesses and freeing of the old cache so a lock is generally
1785 // acquired when the RedefineClasses() API has been used.
1786
1787 if (jmeths != NULL) {
1788 // the cache already exists
1789 if (!idnum_can_increment()) {
1790 // the cache can't grow so we can just get the current values
1791 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1792 } else {
1793 // cache can grow so we have to be more careful
1794 if (Threads::number_of_threads() == 0 ||
1795 SafepointSynchronize::is_at_safepoint()) {
1796 // we're single threaded or at a safepoint - no locking needed
1797 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1798 } else {
1799 MutexLocker ml(JmethodIdCreation_lock);
1800 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1801 }
1802 }
1803 }
1804 // implied else:
1805 // we need to allocate a cache so default length and id values are good
1806
1807 if (jmeths == NULL || // no cache yet
1808 length <= idnum || // cache is too short
1809 id == NULL) { // cache doesn't contain entry
1810
1811 // This function can be called by the VMThread so we have to do all
1812 // things that might block on a safepoint before grabbing the lock.
1813 // Otherwise, we can deadlock with the VMThread or have a cache
1814 // consistency issue. These vars keep track of what we might have
1815 // to free after the lock is dropped.
1816 jmethodID to_dealloc_id = NULL;
1817 jmethodID* to_dealloc_jmeths = NULL;
1818
1819 // may not allocate new_jmeths or use it if we allocate it
1820 jmethodID* new_jmeths = NULL;
1821 if (length <= idnum) {
1822 // allocate a new cache that might be used
1823 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1824 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1825 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1826 // cache size is stored in element[0], other elements offset by one
1827 new_jmeths[0] = (jmethodID)size;
1828 }
1829
1830 // allocate a new jmethodID that might be used
1831 jmethodID new_id = NULL;
1832 if (method_h->is_old() && !method_h->is_obsolete()) {
1833 // The method passed in is old (but not obsolete), we need to use the current version
1834 Method* current_method = method_with_idnum((int)idnum);
1835 assert(current_method != NULL, "old and but not obsolete, so should exist");
1836 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1837 } else {
1838 // It is the current version of the method or an obsolete method,
1839 // use the version passed in
1840 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1841 }
1842
1843 if (Threads::number_of_threads() == 0 ||
1844 SafepointSynchronize::is_at_safepoint()) {
1845 // we're single threaded or at a safepoint - no locking needed
1846 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1847 &to_dealloc_id, &to_dealloc_jmeths);
1848 } else {
1849 MutexLocker ml(JmethodIdCreation_lock);
1850 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1851 &to_dealloc_id, &to_dealloc_jmeths);
1852 }
1853
1854 // The lock has been dropped so we can free resources.
1855 // Free up either the old cache or the new cache if we allocated one.
1856 if (to_dealloc_jmeths != NULL) {
1857 FreeHeap(to_dealloc_jmeths);
1858 }
1859 // free up the new ID since it wasn't needed
1860 if (to_dealloc_id != NULL) {
1861 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
1862 }
1863 }
1864 return id;
1865 }
1866
1867 // Figure out how many jmethodIDs haven't been allocated, and make
1868 // sure space for them is pre-allocated. This makes getting all
1869 // method ids much, much faster with classes with more than 8
1870 // methods, and has a *substantial* effect on performance with jvmti
1871 // code that loads all jmethodIDs for all classes.
1872 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1873 int new_jmeths = 0;
1874 int length = methods()->length();
1875 for (int index = start_offset; index < length; index++) {
1876 Method* m = methods()->at(index);
1877 jmethodID id = m->find_jmethod_id_or_null();
1878 if (id == NULL) {
1879 new_jmeths++;
1880 }
1881 }
1882 if (new_jmeths != 0) {
1883 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1884 }
1885 }
1886
1887 // Common code to fetch the jmethodID from the cache or update the
1888 // cache with the new jmethodID. This function should never do anything
1889 // that causes the caller to go to a safepoint or we can deadlock with
1890 // the VMThread or have cache consistency issues.
1891 //
1892 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1893 size_t idnum, jmethodID new_id,
1894 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1895 jmethodID** to_dealloc_jmeths_p) {
1896 assert(new_id != NULL, "sanity check");
1897 assert(to_dealloc_id_p != NULL, "sanity check");
1898 assert(to_dealloc_jmeths_p != NULL, "sanity check");
1899 assert(Threads::number_of_threads() == 0 ||
1900 SafepointSynchronize::is_at_safepoint() ||
1901 JmethodIdCreation_lock->owned_by_self(), "sanity check");
1902
1903 // reacquire the cache - we are locked, single threaded or at a safepoint
1904 jmethodID* jmeths = methods_jmethod_ids_acquire();
1905 jmethodID id = NULL;
1906 size_t length = 0;
1907
1908 if (jmeths == NULL || // no cache yet
1909 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
1910 if (jmeths != NULL) {
1911 // copy any existing entries from the old cache
1912 for (size_t index = 0; index < length; index++) {
1913 new_jmeths[index+1] = jmeths[index+1];
1914 }
1915 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
1916 }
1917 release_set_methods_jmethod_ids(jmeths = new_jmeths);
1918 } else {
1919 // fetch jmethodID (if any) from the existing cache
1920 id = jmeths[idnum+1];
1921 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
1922 }
1923 if (id == NULL) {
1924 // No matching jmethodID in the existing cache or we have a new
1925 // cache or we just grew the cache. This cache write is done here
1926 // by the first thread to win the foot race because a jmethodID
1927 // needs to be unique once it is generally available.
1928 id = new_id;
1929
1930 // The jmethodID cache can be read while unlocked so we have to
1931 // make sure the new jmethodID is complete before installing it
1932 // in the cache.
1933 OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1934 } else {
1935 *to_dealloc_id_p = new_id; // save new id for later delete
1936 }
1937 return id;
1938 }
1939
1940
1941 // Common code to get the jmethodID cache length and the jmethodID
1942 // value at index idnum if there is one.
1943 //
1944 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1945 size_t idnum, size_t *length_p, jmethodID* id_p) {
1946 assert(cache != NULL, "sanity check");
1947 assert(length_p != NULL, "sanity check");
1948 assert(id_p != NULL, "sanity check");
1949
1950 // cache size is stored in element[0], other elements offset by one
1951 *length_p = (size_t)cache[0];
1952 if (*length_p <= idnum) { // cache is too short
1953 *id_p = NULL;
1954 } else {
1955 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
1956 }
1957 }
1958
1959
1960 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
1961 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1962 size_t idnum = (size_t)method->method_idnum();
1963 jmethodID* jmeths = methods_jmethod_ids_acquire();
1964 size_t length; // length assigned as debugging crumb
1965 jmethodID id = NULL;
1966 if (jmeths != NULL && // If there is a cache
1967 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
1968 id = jmeths[idnum+1]; // Look up the id (may be NULL)
1969 }
1970 return id;
1971 }
1972
1973 inline DependencyContext InstanceKlass::dependencies() {
1974 DependencyContext dep_context(&_dep_context);
1975 return dep_context;
1976 }
1977
1978 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1979 return dependencies().mark_dependent_nmethods(changes);
1980 }
1981
1982 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1983 dependencies().add_dependent_nmethod(nm);
1984 }
1985
1986 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1987 dependencies().remove_dependent_nmethod(nm, delete_immediately);
1988 }
1989
1990 #ifndef PRODUCT
1991 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1992 dependencies().print_dependent_nmethods(verbose);
1993 }
1994
1995 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1996 return dependencies().is_dependent_nmethod(nm);
1997 }
1998 #endif //PRODUCT
1999
2000 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2001 clean_implementors_list(is_alive);
2002 clean_method_data(is_alive);
2003
2004 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2005 DependencyContext dep_context(&_dep_context);
2006 dep_context.expunge_stale_entries();
2007 }
2008
2009 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2010 assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2011 if (is_interface()) {
2012 if (ClassUnloading) {
2013 Klass* impl = implementor();
2014 if (impl != NULL) {
2015 if (!impl->is_loader_alive(is_alive)) {
2016 // remove this guy
2017 Klass** klass = adr_implementor();
2018 assert(klass != NULL, "null klass");
2019 if (klass != NULL) {
2020 *klass = NULL;
2021 }
2022 }
2023 }
2024 }
2025 }
2026 }
2027
2028 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2029 for (int m = 0; m < methods()->length(); m++) {
2030 MethodData* mdo = methods()->at(m)->method_data();
2031 if (mdo != NULL) {
2032 mdo->clean_method_data(is_alive);
2033 }
2034 }
2035 }
2036
2037 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2038 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2039 ResourceMark rm;
2040 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2041 return false;
2042 }
2043
2044 Array<Klass*>* local_interfaces = this->local_interfaces();
2045 if (local_interfaces != NULL) {
2046 int length = local_interfaces->length();
2047 for (int i = 0; i < length; i++) {
2048 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
2049 if (!intf->has_passed_fingerprint_check()) {
2050 ResourceMark rm;
2051 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2052 return false;
2053 }
2054 }
2055 }
2056
2057 return true;
2058 }
2059
2060 bool InstanceKlass::should_store_fingerprint() {
2061 #if INCLUDE_AOT
2062 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2063 if (EnableJVMCI && !UseJVMCICompiler) {
2064 // (1) We are running AOT to generate a shared library.
2065 return true;
2066 }
2067 if (DumpSharedSpaces) {
2068 // (2) We are running -Xshare:dump to create a shared archive
2069 return true;
2070 }
2071 #endif
2072
2073 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2074 // but do not store the 64-bit fingerprint to save space.
2075 return false;
2076 }
2077
2078 bool InstanceKlass::has_stored_fingerprint() const {
2079 #if INCLUDE_AOT
2080 return should_store_fingerprint() || is_shared();
2081 #else
2082 return false;
2083 #endif
2084 }
2085
2086 uint64_t InstanceKlass::get_stored_fingerprint() const {
2087 address adr = adr_fingerprint();
2088 if (adr != NULL) {
2089 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2090 }
2091 return 0;
2092 }
2093
2094 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2095 address adr = adr_fingerprint();
2096 if (adr != NULL) {
2097 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2098
2099 ResourceMark rm;
2100 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2101 }
2102 }
2103
2104 static void remove_unshareable_in_class(Klass* k) {
2105 // remove klass's unshareable info
2106 k->remove_unshareable_info();
2107 }
2108
2109 void InstanceKlass::remove_unshareable_info() {
2110 Klass::remove_unshareable_info();
2111 // Unlink the class
2112 if (is_linked()) {
2113 unlink_class();
2114 }
2115 init_implementor();
2116
2117 constants()->remove_unshareable_info();
2118
2119 assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable");
2120
2121 for (int i = 0; i < methods()->length(); i++) {
2122 Method* m = methods()->at(i);
2123 m->remove_unshareable_info();
2124 }
2125
2126 // do array classes also.
2127 array_klasses_do(remove_unshareable_in_class);
2128 }
2129
2130 static void restore_unshareable_in_class(Klass* k, TRAPS) {
2131 // Array classes have null protection domain.
2132 // --> see ArrayKlass::complete_create_array_klass()
2133 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2134 }
2135
2136 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2137 set_package(loader_data, CHECK);
2138 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2139
2140 Array<Method*>* methods = this->methods();
2141 int num_methods = methods->length();
2142 for (int index2 = 0; index2 < num_methods; ++index2) {
2143 methodHandle m(THREAD, methods->at(index2));
2144 m->restore_unshareable_info(CHECK);
2145 }
2146 if (JvmtiExport::has_redefined_a_class()) {
2147 // Reinitialize vtable because RedefineClasses may have changed some
2148 // entries in this vtable for super classes so the CDS vtable might
2149 // point to old or obsolete entries. RedefineClasses doesn't fix up
2150 // vtables in the shared system dictionary, only the main one.
2151 // It also redefines the itable too so fix that too.
2152 ResourceMark rm(THREAD);
2153 vtable().initialize_vtable(false, CHECK);
2154 itable().initialize_itable(false, CHECK);
2155 }
2156
2157 // restore constant pool resolved references
2158 constants()->restore_unshareable_info(CHECK);
2159
2160 array_klasses_do(restore_unshareable_in_class, CHECK);
2161 }
2162
2163 // returns true IFF is_in_error_state() has been changed as a result of this call.
2164 bool InstanceKlass::check_sharing_error_state() {
2165 assert(DumpSharedSpaces, "should only be called during dumping");
2166 bool old_state = is_in_error_state();
2167
2168 if (!is_in_error_state()) {
2169 bool bad = false;
2170 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2171 if (sup->is_in_error_state()) {
2172 bad = true;
2173 break;
2174 }
2175 }
2176 if (!bad) {
2177 Array<Klass*>* interfaces = transitive_interfaces();
2178 for (int i = 0; i < interfaces->length(); i++) {
2179 Klass* iface = interfaces->at(i);
2180 if (InstanceKlass::cast(iface)->is_in_error_state()) {
2181 bad = true;
2182 break;
2183 }
2184 }
2185 }
2186
2187 if (bad) {
2188 set_in_error_state();
2189 }
2190 }
2191
2192 return (old_state != is_in_error_state());
2193 }
2194
2195 #if INCLUDE_JVMTI
2196 static void clear_all_breakpoints(Method* m) {
2197 m->clear_all_breakpoints();
2198 }
2199 #endif
2200
2201 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2202 // notify the debugger
2203 if (JvmtiExport::should_post_class_unload()) {
2204 JvmtiExport::post_class_unload(ik);
2205 }
2206
2207 // notify ClassLoadingService of class unload
2208 ClassLoadingService::notify_class_unloaded(ik);
2209 }
2210
2211 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2212 // Clean up C heap
2213 ik->release_C_heap_structures();
2214 ik->constants()->release_C_heap_structures();
2215 }
2216
2217 void InstanceKlass::release_C_heap_structures() {
2218 // Can't release the constant pool here because the constant pool can be
2219 // deallocated separately from the InstanceKlass for default methods and
2220 // redefine classes.
2221
2222 // Deallocate oop map cache
2223 if (_oop_map_cache != NULL) {
2224 delete _oop_map_cache;
2225 _oop_map_cache = NULL;
2226 }
2227
2228 // Deallocate JNI identifiers for jfieldIDs
2229 JNIid::deallocate(jni_ids());
2230 set_jni_ids(NULL);
2231
2232 jmethodID* jmeths = methods_jmethod_ids_acquire();
2233 if (jmeths != (jmethodID*)NULL) {
2234 release_set_methods_jmethod_ids(NULL);
2235 FreeHeap(jmeths);
2236 }
2237
2238 // Deallocate MemberNameTable
2239 {
2240 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2241 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2242 MemberNameTable* mnt = member_names();
2243 if (mnt != NULL) {
2244 delete mnt;
2245 set_member_names(NULL);
2246 }
2247 }
2248
2249 // Release dependencies.
2250 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2251 // it is not safe (see JDK-8143408). The problem is that the klass dependency
2252 // context can contain live dependencies, since there's a race between nmethod &
2253 // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2254 // dependencies aren't removed from the context associated with the class (see
2255 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2256 // live dependencies pointing to unloaded nmethods and causes a crash in
2257 // DC::remove_all_dependents() when it touches unloaded nmethod.
2258 dependencies().wipe();
2259
2260 #if INCLUDE_JVMTI
2261 // Deallocate breakpoint records
2262 if (breakpoints() != 0x0) {
2263 methods_do(clear_all_breakpoints);
2264 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2265 }
2266
2267 // deallocate the cached class file
2268 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_space(_cached_class_file)) {
2269 os::free(_cached_class_file);
2270 _cached_class_file = NULL;
2271 }
2272 #endif
2273
2274 // Decrement symbol reference counts associated with the unloaded class.
2275 if (_name != NULL) _name->decrement_refcount();
2276 // unreference array name derived from this class name (arrays of an unloaded
2277 // class can't be referenced anymore).
2278 if (_array_name != NULL) _array_name->decrement_refcount();
2279 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2280
2281 assert(_total_instanceKlass_count >= 1, "Sanity check");
2282 Atomic::dec(&_total_instanceKlass_count);
2283 }
2284
2285 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2286 if (array == NULL) {
2287 _source_debug_extension = NULL;
2288 } else {
2289 // Adding one to the attribute length in order to store a null terminator
2290 // character could cause an overflow because the attribute length is
2291 // already coded with an u4 in the classfile, but in practice, it's
2292 // unlikely to happen.
2293 assert((length+1) > length, "Overflow checking");
2294 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2295 for (int i = 0; i < length; i++) {
2296 sde[i] = array[i];
2297 }
2298 sde[length] = '\0';
2299 _source_debug_extension = sde;
2300 }
2301 }
2302
2303 address InstanceKlass::static_field_addr(int offset) {
2304 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2305 }
2306
2307
2308 const char* InstanceKlass::signature_name() const {
2309 int hash_len = 0;
2310 char hash_buf[40];
2311
2312 // If this is an anonymous class, append a hash to make the name unique
2313 if (is_anonymous()) {
2314 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2315 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2316 hash_len = (int)strlen(hash_buf);
2317 }
2318
2319 // Get the internal name as a c string
2320 const char* src = (const char*) (name()->as_C_string());
2321 const int src_length = (int)strlen(src);
2322
2323 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2324
2325 // Add L as type indicator
2326 int dest_index = 0;
2327 dest[dest_index++] = is_value_type_klass() ? 'Q' : 'L';
2328
2329 // Add the actual class name
2330 for (int src_index = 0; src_index < src_length; ) {
2331 dest[dest_index++] = src[src_index++];
2332 }
2333
2334 // If we have a hash, append it
2335 for (int hash_index = 0; hash_index < hash_len; ) {
2336 dest[dest_index++] = hash_buf[hash_index++];
2337 }
2338
2339 // Add the semicolon and the NULL
2340 dest[dest_index++] = ';';
2341 dest[dest_index] = '\0';
2342 return dest;
2343 }
2344
2345 // Used to obtain the package name from a fully qualified class name.
2346 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2347 if (name == NULL) {
2348 return NULL;
2349 } else {
2350 if (name->utf8_length() <= 0) {
2351 return NULL;
2352 }
2353 ResourceMark rm;
2354 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2355 if (package_name == NULL) {
2356 return NULL;
2357 }
2358 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2359 return pkg_name;
2360 }
2361 }
2362
2363 ModuleEntry* InstanceKlass::module() const {
2364 if (!in_unnamed_package()) {
2365 return _package_entry->module();
2366 }
2367 const Klass* host = host_klass();
2368 if (host == NULL) {
2369 return class_loader_data()->unnamed_module();
2370 }
2371 return host->class_loader_data()->unnamed_module();
2372 }
2373
2374 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2375
2376 // ensure java/ packages only loaded by boot or platform builtin loaders
2377 Handle class_loader(THREAD, loader_data->class_loader());
2378 check_prohibited_package(name(), class_loader, CHECK);
2379
2380 TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2381
2382 if (pkg_name != NULL && loader_data != NULL) {
2383
2384 // Find in class loader's package entry table.
2385 _package_entry = loader_data->packages()->lookup_only(pkg_name);
2386
2387 // If the package name is not found in the loader's package
2388 // entry table, it is an indication that the package has not
2389 // been defined. Consider it defined within the unnamed module.
2390 if (_package_entry == NULL) {
2391 ResourceMark rm;
2392
2393 if (!ModuleEntryTable::javabase_defined()) {
2394 // Before java.base is defined during bootstrapping, define all packages in
2395 // the java.base module. If a non-java.base package is erroneously placed
2396 // in the java.base module it will be caught later when java.base
2397 // is defined by ModuleEntryTable::verify_javabase_packages check.
2398 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2399 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2400 } else {
2401 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2402 _package_entry = loader_data->packages()->lookup(pkg_name,
2403 loader_data->unnamed_module());
2404 }
2405
2406 // A package should have been successfully created
2407 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2408 name()->as_C_string(), loader_data->loader_name());
2409 }
2410
2411 if (log_is_enabled(Debug, module)) {
2412 ResourceMark rm;
2413 ModuleEntry* m = _package_entry->module();
2414 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2415 external_name(),
2416 pkg_name->as_C_string(),
2417 loader_data->loader_name(),
2418 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2419 }
2420 } else {
2421 ResourceMark rm;
2422 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2423 external_name(),
2424 (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2425 UNNAMED_MODULE);
2426 }
2427 }
2428
2429
2430 // different versions of is_same_class_package
2431
2432 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2433 oop classloader1 = this->class_loader();
2434 PackageEntry* classpkg1 = this->package();
2435 if (class2->is_objArray_klass()) {
2436 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2437 }
2438
2439 oop classloader2;
2440 PackageEntry* classpkg2;
2441 if (class2->is_instance_klass()) {
2442 classloader2 = class2->class_loader();
2443 classpkg2 = class2->package();
2444 } else {
2445 assert(class2->is_typeArray_klass(), "should be type array");
2446 classloader2 = NULL;
2447 classpkg2 = NULL;
2448 }
2449
2450 // Same package is determined by comparing class loader
2451 // and package entries. Both must be the same. This rule
2452 // applies even to classes that are defined in the unnamed
2453 // package, they still must have the same class loader.
2454 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2455 return true;
2456 }
2457
2458 return false;
2459 }
2460
2461 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2462 const Symbol* other_class_name) const {
2463 oop this_class_loader = class_loader();
2464 const Symbol* const this_class_name = name();
2465
2466 return InstanceKlass::is_same_class_package(this_class_loader,
2467 this_class_name,
2468 other_class_loader,
2469 other_class_name);
2470 }
2471
2472 // return true if two classes are in the same package, classloader
2473 // and classname information is enough to determine a class's package
2474 bool InstanceKlass::is_same_class_package(oop class_loader1, const Symbol* class_name1,
2475 oop class_loader2, const Symbol* class_name2) {
2476 if (class_loader1 != class_loader2) {
2477 return false;
2478 } else if (class_name1 == class_name2) {
2479 return true;
2480 } else {
2481 ResourceMark rm;
2482
2483 bool bad_class_name = false;
2484 const char* name1 = ClassLoader::package_from_name((const char*) class_name1->as_C_string(), &bad_class_name);
2485 if (bad_class_name) {
2486 return false;
2487 }
2488
2489 const char* name2 = ClassLoader::package_from_name((const char*) class_name2->as_C_string(), &bad_class_name);
2490 if (bad_class_name) {
2491 return false;
2492 }
2493
2494 if ((name1 == NULL) || (name2 == NULL)) {
2495 // One of the two doesn't have a package. Only return true
2496 // if the other one also doesn't have a package.
2497 return name1 == name2;
2498 }
2499
2500 // Check that package is identical
2501 return (strcmp(name1, name2) == 0);
2502 }
2503 }
2504
2505 // Returns true iff super_method can be overridden by a method in targetclassname
2506 // See JLS 3rd edition 8.4.6.1
2507 // Assumes name-signature match
2508 // "this" is InstanceKlass of super_method which must exist
2509 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2510 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2511 // Private methods can not be overridden
2512 if (super_method->is_private()) {
2513 return false;
2514 }
2515 // If super method is accessible, then override
2516 if ((super_method->is_protected()) ||
2517 (super_method->is_public())) {
2518 return true;
2519 }
2520 // Package-private methods are not inherited outside of package
2521 assert(super_method->is_package_private(), "must be package private");
2522 return(is_same_class_package(targetclassloader(), targetclassname));
2523 }
2524
2525 // Only boot and platform class loaders can define classes in "java/" packages.
2526 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2527 Handle class_loader,
2528 TRAPS) {
2529 if (!class_loader.is_null() &&
2530 !SystemDictionary::is_platform_class_loader(class_loader()) &&
2531 class_name != NULL) {
2532 ResourceMark rm(THREAD);
2533 char* name = class_name->as_C_string();
2534 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2535 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2536 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2537 name = pkg_name->as_C_string();
2538 const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2539 StringUtils::replace_no_expand(name, "/", ".");
2540 const char* msg_text1 = "Class loader (instance of): ";
2541 const char* msg_text2 = " tried to load prohibited package name: ";
2542 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2543 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2544 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2545 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2546 }
2547 }
2548 return;
2549 }
2550
2551 // tell if two classes have the same enclosing class (at package level)
2552 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const {
2553 if (class2 == this) return true;
2554 if (!class2->is_instance_klass()) return false;
2555
2556 // must be in same package before we try anything else
2557 if (!is_same_class_package(class2))
2558 return false;
2559
2560 // As long as there is an outer_this.getEnclosingClass,
2561 // shift the search outward.
2562 const InstanceKlass* outer_this = this;
2563 for (;;) {
2564 // As we walk along, look for equalities between outer_this and class2.
2565 // Eventually, the walks will terminate as outer_this stops
2566 // at the top-level class around the original class.
2567 bool ignore_inner_is_member;
2568 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member,
2569 CHECK_false);
2570 if (next == NULL) break;
2571 if (next == class2) return true;
2572 outer_this = InstanceKlass::cast(next);
2573 }
2574
2575 // Now do the same for class2.
2576 const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2577 for (;;) {
2578 bool ignore_inner_is_member;
2579 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2580 CHECK_false);
2581 if (next == NULL) break;
2582 // Might as well check the new outer against all available values.
2583 if (next == this) return true;
2584 if (next == outer_this) return true;
2585 outer2 = InstanceKlass::cast(next);
2586 }
2587
2588 // If by this point we have not found an equality between the
2589 // two classes, we know they are in separate package members.
2590 return false;
2591 }
2592
2593 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2594 constantPoolHandle i_cp(THREAD, constants());
2595 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2596 int ioff = iter.inner_class_info_index();
2597 if (ioff != 0) {
2598 // Check to see if the name matches the class we're looking for
2599 // before attempting to find the class.
2600 if (i_cp->klass_name_at_matches(this, ioff)) {
2601 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2602 if (this == inner_klass) {
2603 *ooff = iter.outer_class_info_index();
2604 *noff = iter.inner_name_index();
2605 return true;
2606 }
2607 }
2608 }
2609 }
2610 return false;
2611 }
2612
2613 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2614 InstanceKlass* outer_klass = NULL;
2615 *inner_is_member = false;
2616 int ooff = 0, noff = 0;
2617 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2618 if (has_inner_classes_attr) {
2619 constantPoolHandle i_cp(THREAD, constants());
2620 if (ooff != 0) {
2621 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2622 outer_klass = InstanceKlass::cast(ok);
2623 *inner_is_member = true;
2624 }
2625 if (NULL == outer_klass) {
2626 // It may be anonymous; try for that.
2627 int encl_method_class_idx = enclosing_method_class_index();
2628 if (encl_method_class_idx != 0) {
2629 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2630 outer_klass = InstanceKlass::cast(ok);
2631 *inner_is_member = false;
2632 }
2633 }
2634 }
2635
2636 // If no inner class attribute found for this class.
2637 if (NULL == outer_klass) return NULL;
2638
2639 // Throws an exception if outer klass has not declared k as an inner klass
2640 // We need evidence that each klass knows about the other, or else
2641 // the system could allow a spoof of an inner class to gain access rights.
2642 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2643 return outer_klass;
2644 }
2645
2646 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2647 jint access = access_flags().as_int();
2648
2649 // But check if it happens to be member class.
2650 InnerClassesIterator iter(this);
2651 for (; !iter.done(); iter.next()) {
2652 int ioff = iter.inner_class_info_index();
2653 // Inner class attribute can be zero, skip it.
2654 // Strange but true: JVM spec. allows null inner class refs.
2655 if (ioff == 0) continue;
2656
2657 // only look at classes that are already loaded
2658 // since we are looking for the flags for our self.
2659 Symbol* inner_name = constants()->klass_name_at(ioff);
2660 if (name() == inner_name) {
2661 // This is really a member class.
2662 access = iter.inner_access_flags();
2663 break;
2664 }
2665 }
2666 // Remember to strip ACC_SUPER bit
2667 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2668 }
2669
2670 jint InstanceKlass::jvmti_class_status() const {
2671 jint result = 0;
2672
2673 if (is_linked()) {
2674 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2675 }
2676
2677 if (is_initialized()) {
2678 assert(is_linked(), "Class status is not consistent");
2679 result |= JVMTI_CLASS_STATUS_INITIALIZED;
2680 }
2681 if (is_in_error_state()) {
2682 result |= JVMTI_CLASS_STATUS_ERROR;
2683 }
2684 return result;
2685 }
2686
2687 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2688 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2689 int method_table_offset_in_words = ioe->offset()/wordSize;
2690 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2691 / itableOffsetEntry::size();
2692
2693 for (int cnt = 0 ; ; cnt ++, ioe ++) {
2694 // If the interface isn't implemented by the receiver class,
2695 // the VM should throw IncompatibleClassChangeError.
2696 if (cnt >= nof_interfaces) {
2697 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2698 }
2699
2700 Klass* ik = ioe->interface_klass();
2701 if (ik == holder) break;
2702 }
2703
2704 itableMethodEntry* ime = ioe->first_method_entry(this);
2705 Method* m = ime[index].method();
2706 if (m == NULL) {
2707 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2708 }
2709 return m;
2710 }
2711
2712
2713 #if INCLUDE_JVMTI
2714 // update default_methods for redefineclasses for methods that are
2715 // not yet in the vtable due to concurrent subclass define and superinterface
2716 // redefinition
2717 // Note: those in the vtable, should have been updated via adjust_method_entries
2718 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2719 // search the default_methods for uses of either obsolete or EMCP methods
2720 if (default_methods() != NULL) {
2721 for (int index = 0; index < default_methods()->length(); index ++) {
2722 Method* old_method = default_methods()->at(index);
2723 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2724 continue; // skip uninteresting entries
2725 }
2726 assert(!old_method->is_deleted(), "default methods may not be deleted");
2727
2728 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2729
2730 assert(new_method != NULL, "method_with_idnum() should not be NULL");
2731 assert(old_method != new_method, "sanity check");
2732
2733 default_methods()->at_put(index, new_method);
2734 if (log_is_enabled(Info, redefine, class, update)) {
2735 ResourceMark rm;
2736 if (!(*trace_name_printed)) {
2737 log_info(redefine, class, update)
2738 ("adjust: klassname=%s default methods from name=%s",
2739 external_name(), old_method->method_holder()->external_name());
2740 *trace_name_printed = true;
2741 }
2742 log_debug(redefine, class, update, vtables)
2743 ("default method update: %s(%s) ",
2744 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2745 }
2746 }
2747 }
2748 }
2749 #endif // INCLUDE_JVMTI
2750
2751 // On-stack replacement stuff
2752 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2753 // only one compilation can be active
2754 {
2755 // This is a short non-blocking critical region, so the no safepoint check is ok.
2756 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2757 assert(n->is_osr_method(), "wrong kind of nmethod");
2758 n->set_osr_link(osr_nmethods_head());
2759 set_osr_nmethods_head(n);
2760 // Raise the highest osr level if necessary
2761 if (TieredCompilation) {
2762 Method* m = n->method();
2763 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2764 }
2765 }
2766
2767 // Get rid of the osr methods for the same bci that have lower levels.
2768 if (TieredCompilation) {
2769 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2770 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2771 if (inv != NULL && inv->is_in_use()) {
2772 inv->make_not_entrant();
2773 }
2774 }
2775 }
2776 }
2777
2778 // Remove osr nmethod from the list. Return true if found and removed.
2779 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2780 // This is a short non-blocking critical region, so the no safepoint check is ok.
2781 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2782 assert(n->is_osr_method(), "wrong kind of nmethod");
2783 nmethod* last = NULL;
2784 nmethod* cur = osr_nmethods_head();
2785 int max_level = CompLevel_none; // Find the max comp level excluding n
2786 Method* m = n->method();
2787 // Search for match
2788 bool found = false;
2789 while(cur != NULL && cur != n) {
2790 if (TieredCompilation && m == cur->method()) {
2791 // Find max level before n
2792 max_level = MAX2(max_level, cur->comp_level());
2793 }
2794 last = cur;
2795 cur = cur->osr_link();
2796 }
2797 nmethod* next = NULL;
2798 if (cur == n) {
2799 found = true;
2800 next = cur->osr_link();
2801 if (last == NULL) {
2802 // Remove first element
2803 set_osr_nmethods_head(next);
2804 } else {
2805 last->set_osr_link(next);
2806 }
2807 }
2808 n->set_osr_link(NULL);
2809 if (TieredCompilation) {
2810 cur = next;
2811 while (cur != NULL) {
2812 // Find max level after n
2813 if (m == cur->method()) {
2814 max_level = MAX2(max_level, cur->comp_level());
2815 }
2816 cur = cur->osr_link();
2817 }
2818 m->set_highest_osr_comp_level(max_level);
2819 }
2820 return found;
2821 }
2822
2823 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2824 // This is a short non-blocking critical region, so the no safepoint check is ok.
2825 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2826 nmethod* osr = osr_nmethods_head();
2827 int found = 0;
2828 while (osr != NULL) {
2829 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2830 if (osr->method() == m) {
2831 osr->mark_for_deoptimization();
2832 found++;
2833 }
2834 osr = osr->osr_link();
2835 }
2836 return found;
2837 }
2838
2839 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2840 // This is a short non-blocking critical region, so the no safepoint check is ok.
2841 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2842 nmethod* osr = osr_nmethods_head();
2843 nmethod* best = NULL;
2844 while (osr != NULL) {
2845 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2846 // There can be a time when a c1 osr method exists but we are waiting
2847 // for a c2 version. When c2 completes its osr nmethod we will trash
2848 // the c1 version and only be able to find the c2 version. However
2849 // while we overflow in the c1 code at back branches we don't want to
2850 // try and switch to the same code as we are already running
2851
2852 if (osr->method() == m &&
2853 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2854 if (match_level) {
2855 if (osr->comp_level() == comp_level) {
2856 // Found a match - return it.
2857 return osr;
2858 }
2859 } else {
2860 if (best == NULL || (osr->comp_level() > best->comp_level())) {
2861 if (osr->comp_level() == CompLevel_highest_tier) {
2862 // Found the best possible - return it.
2863 return osr;
2864 }
2865 best = osr;
2866 }
2867 }
2868 }
2869 osr = osr->osr_link();
2870 }
2871 if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2872 return best;
2873 }
2874 return NULL;
2875 }
2876
2877 oop InstanceKlass::add_member_name(Handle mem_name, bool intern) {
2878 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2879 MutexLocker ml(MemberNameTable_lock);
2880 DEBUG_ONLY(NoSafepointVerifier nsv);
2881
2882 // Check if method has been redefined while taking out MemberNameTable_lock, if so
2883 // return false. We cannot cache obsolete methods. They will crash when the function
2884 // is called!
2885 Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
2886 if (method->is_obsolete()) {
2887 return NULL;
2888 } else if (method->is_old()) {
2889 // Replace method with redefined version
2890 java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
2891 }
2892
2893 if (_member_names == NULL) {
2894 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2895 }
2896 if (intern) {
2897 return _member_names->find_or_add_member_name(mem_name_wref);
2898 } else {
2899 return _member_names->add_member_name(mem_name_wref);
2900 }
2901 }
2902
2903 // -----------------------------------------------------------------------------------------------------
2904 // Printing
2905
2906 #ifndef PRODUCT
2907
2908 #define BULLET " - "
2909
2910 static const char* state_names[] = {
2911 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2912 };
2913
2914 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
2915 ResourceMark rm;
2916 int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
2917 for (int i = 0; i < len; i++) forward_refs[i] = 0;
2918 for (int i = 0; i < len; i++) {
2919 intptr_t e = start[i];
2920 st->print("%d : " INTPTR_FORMAT, i, e);
2921 if (forward_refs[i] != 0) {
2922 int from = forward_refs[i];
2923 int off = (int) start[from];
2924 st->print(" (offset %d <= [%d])", off, from);
2925 }
2926 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2927 st->print(" ");
2928 ((Metadata*)e)->print_value_on(st);
2929 } else if (self != NULL && e > 0 && e < 0x10000) {
2930 address location = self + e;
2931 int index = (int)((intptr_t*)location - start);
2932 st->print(" (offset %d => [%d])", (int)e, index);
2933 if (index >= 0 && index < len)
2934 forward_refs[index] = i;
2935 }
2936 st->cr();
2937 }
2938 }
2939
2940 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2941 return print_vtable(NULL, reinterpret_cast<intptr_t*>(start), len, st);
2942 }
2943
2944 template<typename T>
2945 static void print_array_on(outputStream* st, Array<T>* array) {
2946 if (array == NULL) { st->print_cr("NULL"); return; }
2947 array->print_value_on(st); st->cr();
2948 if (Verbose || WizardMode) {
2949 for (int i = 0; i < array->length(); i++) {
2950 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
2951 }
2952 }
2953 }
2954
2955 static void print_array_on(outputStream* st, Array<int>* array) {
2956 if (array == NULL) { st->print_cr("NULL"); return; }
2957 array->print_value_on(st); st->cr();
2958 if (Verbose || WizardMode) {
2959 for (int i = 0; i < array->length(); i++) {
2960 st->print("%d : %d", i, array->at(i)); st->cr();
2961 }
2962 }
2963 }
2964
2965 void InstanceKlass::print_on(outputStream* st) const {
2966 assert(is_klass(), "must be klass");
2967 Klass::print_on(st);
2968
2969 st->print(BULLET"instance size: %d", size_helper()); st->cr();
2970 st->print(BULLET"klass size: %d", size()); st->cr();
2971 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
2972 st->print(BULLET"misc flags: 0x%x", _misc_flags); st->cr();
2973 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
2974 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
2975 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr();
2976 st->print(BULLET"sub: ");
2977 Klass* sub = subklass();
2978 int n;
2979 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2980 if (n < MaxSubklassPrintSize) {
2981 sub->print_value_on(st);
2982 st->print(" ");
2983 }
2984 }
2985 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2986 st->cr();
2987
2988 if (is_interface()) {
2989 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
2990 if (nof_implementors() == 1) {
2991 st->print_cr(BULLET"implementor: ");
2992 st->print(" ");
2993 implementor()->print_value_on(st);
2994 st->cr();
2995 }
2996 }
2997
2998 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2999 st->print(BULLET"methods: "); print_array_on(st, methods());
3000 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering());
3001 st->print(BULLET"default_methods: "); print_array_on(st, default_methods());
3002 if (default_vtable_indices() != NULL) {
3003 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices());
3004 }
3005 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces());
3006 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
3007 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3008 if (class_loader_data() != NULL) {
3009 st->print(BULLET"class loader data: ");
3010 class_loader_data()->print_value_on(st);
3011 st->cr();
3012 }
3013 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr();
3014 if (source_file_name() != NULL) {
3015 st->print(BULLET"source file: ");
3016 source_file_name()->print_value_on(st);
3017 st->cr();
3018 }
3019 if (source_debug_extension() != NULL) {
3020 st->print(BULLET"source debug extension: ");
3021 st->print("%s", source_debug_extension());
3022 st->cr();
3023 }
3024 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3025 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3026 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3027 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3028 {
3029 bool have_pv = false;
3030 // previous versions are linked together through the InstanceKlass
3031 for (InstanceKlass* pv_node = previous_versions();
3032 pv_node != NULL;
3033 pv_node = pv_node->previous_versions()) {
3034 if (!have_pv)
3035 st->print(BULLET"previous version: ");
3036 have_pv = true;
3037 pv_node->constants()->print_value_on(st);
3038 }
3039 if (have_pv) st->cr();
3040 }
3041
3042 if (generic_signature() != NULL) {
3043 st->print(BULLET"generic signature: ");
3044 generic_signature()->print_value_on(st);
3045 st->cr();
3046 }
3047 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3048 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr();
3049 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3050 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3051 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3052 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(NULL, start_of_itable(), itable_length(), st);
3053 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3054 FieldPrinter print_static_field(st);
3055 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3056 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3057 FieldPrinter print_nonstatic_field(st);
3058 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3059 ik->do_nonstatic_fields(&print_nonstatic_field);
3060
3061 st->print(BULLET"non-static oop maps: ");
3062 OopMapBlock* map = start_of_nonstatic_oop_maps();
3063 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3064 while (map < end_map) {
3065 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3066 map++;
3067 }
3068 st->cr();
3069 }
3070
3071 #endif //PRODUCT
3072
3073 void InstanceKlass::print_value_on(outputStream* st) const {
3074 assert(is_klass(), "must be klass");
3075 if (Verbose || WizardMode) access_flags().print_on(st);
3076 name()->print_value_on(st);
3077 }
3078
3079 #ifndef PRODUCT
3080
3081 void FieldPrinter::do_field(fieldDescriptor* fd) {
3082 _st->print(BULLET);
3083 if (_obj == NULL) {
3084 fd->print_on(_st);
3085 _st->cr();
3086 } else {
3087 fd->print_on_for(_st, _obj);
3088 _st->cr();
3089 }
3090 }
3091
3092
3093 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3094 Klass::oop_print_on(obj, st);
3095
3096 if (this == SystemDictionary::String_klass()) {
3097 typeArrayOop value = java_lang_String::value(obj);
3098 juint length = java_lang_String::length(obj);
3099 if (value != NULL &&
3100 value->is_typeArray() &&
3101 length <= (juint) value->length()) {
3102 st->print(BULLET"string: ");
3103 java_lang_String::print(obj, st);
3104 st->cr();
3105 if (!WizardMode) return; // that is enough
3106 }
3107 }
3108
3109 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3110 FieldPrinter print_field(st, obj);
3111 do_nonstatic_fields(&print_field);
3112
3113 if (this == SystemDictionary::Class_klass()) {
3114 st->print(BULLET"signature: ");
3115 java_lang_Class::print_signature(obj, st);
3116 st->cr();
3117 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3118 st->print(BULLET"fake entry for mirror: ");
3119 mirrored_klass->print_value_on_maybe_null(st);
3120 st->cr();
3121 Klass* array_klass = java_lang_Class::array_klass(obj);
3122 st->print(BULLET"fake entry for array: ");
3123 array_klass->print_value_on_maybe_null(st);
3124 st->cr();
3125 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3126 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3127 Klass* real_klass = java_lang_Class::as_Klass(obj);
3128 if (real_klass != NULL && real_klass->is_instance_klass()) {
3129 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3130 }
3131 } else if (this == SystemDictionary::MethodType_klass()) {
3132 st->print(BULLET"signature: ");
3133 java_lang_invoke_MethodType::print_signature(obj, st);
3134 st->cr();
3135 }
3136 }
3137
3138 #endif //PRODUCT
3139
3140 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3141 st->print("a ");
3142 name()->print_value_on(st);
3143 obj->print_address_on(st);
3144 if (this == SystemDictionary::String_klass()
3145 && java_lang_String::value(obj) != NULL) {
3146 ResourceMark rm;
3147 int len = java_lang_String::length(obj);
3148 int plen = (len < 24 ? len : 12);
3149 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3150 st->print(" = \"%s\"", str);
3151 if (len > plen)
3152 st->print("...[%d]", len);
3153 } else if (this == SystemDictionary::Class_klass()) {
3154 Klass* k = java_lang_Class::as_Klass(obj);
3155 st->print(" = ");
3156 if (k != NULL) {
3157 k->print_value_on(st);
3158 } else {
3159 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3160 st->print("%s", tname ? tname : "type?");
3161 }
3162 } else if (this == SystemDictionary::MethodType_klass()) {
3163 st->print(" = ");
3164 java_lang_invoke_MethodType::print_signature(obj, st);
3165 } else if (java_lang_boxing_object::is_instance(obj)) {
3166 st->print(" = ");
3167 java_lang_boxing_object::print(obj, st);
3168 } else if (this == SystemDictionary::LambdaForm_klass()) {
3169 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3170 if (vmentry != NULL) {
3171 st->print(" => ");
3172 vmentry->print_value_on(st);
3173 }
3174 } else if (this == SystemDictionary::MemberName_klass()) {
3175 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3176 if (vmtarget != NULL) {
3177 st->print(" = ");
3178 vmtarget->print_value_on(st);
3179 } else {
3180 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3181 st->print(".");
3182 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3183 }
3184 }
3185 }
3186
3187 const char* InstanceKlass::internal_name() const {
3188 return external_name();
3189 }
3190
3191 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3192 const char* module_name,
3193 const ClassFileStream* cfs) const {
3194 if (!log_is_enabled(Info, class, load)) {
3195 return;
3196 }
3197
3198 ResourceMark rm;
3199 LogMessage(class, load) msg;
3200 stringStream info_stream;
3201
3202 // Name and class hierarchy info
3203 info_stream.print("%s", external_name());
3204
3205 // Source
3206 if (cfs != NULL) {
3207 if (cfs->source() != NULL) {
3208 if (module_name != NULL) {
3209 if (ClassLoader::is_jrt(cfs->source())) {
3210 info_stream.print(" source: jrt:/%s", module_name);
3211 } else {
3212 info_stream.print(" source: %s", cfs->source());
3213 }
3214 } else {
3215 info_stream.print(" source: %s", cfs->source());
3216 }
3217 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3218 Thread* THREAD = Thread::current();
3219 Klass* caller =
3220 THREAD->is_Java_thread()
3221 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3222 : NULL;
3223 // caller can be NULL, for example, during a JVMTI VM_Init hook
3224 if (caller != NULL) {
3225 info_stream.print(" source: instance of %s", caller->external_name());
3226 } else {
3227 // source is unknown
3228 }
3229 } else {
3230 oop class_loader = loader_data->class_loader();
3231 info_stream.print(" source: %s", class_loader->klass()->external_name());
3232 }
3233 } else {
3234 info_stream.print(" source: shared objects file");
3235 }
3236
3237 msg.info("%s", info_stream.as_string());
3238
3239 if (log_is_enabled(Debug, class, load)) {
3240 stringStream debug_stream;
3241
3242 // Class hierarchy info
3243 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3244 p2i(this), p2i(superklass()));
3245
3246 // Interfaces
3247 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3248 debug_stream.print(" interfaces:");
3249 int length = local_interfaces()->length();
3250 for (int i = 0; i < length; i++) {
3251 debug_stream.print(" " INTPTR_FORMAT,
3252 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3253 }
3254 }
3255
3256 // Class loader
3257 debug_stream.print(" loader: [");
3258 loader_data->print_value_on(&debug_stream);
3259 debug_stream.print("]");
3260
3261 // Classfile checksum
3262 if (cfs) {
3263 debug_stream.print(" bytes: %d checksum: %08x",
3264 cfs->length(),
3265 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3266 cfs->length()));
3267 }
3268
3269 msg.debug("%s", debug_stream.as_string());
3270 }
3271 }
3272
3273 #if INCLUDE_SERVICES
3274 // Size Statistics
3275 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3276 Klass::collect_statistics(sz);
3277
3278 sz->_inst_size = wordSize * size_helper();
3279 sz->_vtab_bytes = wordSize * vtable_length();
3280 sz->_itab_bytes = wordSize * itable_length();
3281 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3282
3283 int n = 0;
3284 n += (sz->_methods_array_bytes = sz->count_array(methods()));
3285 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering()));
3286 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces()));
3287 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3288 n += (sz->_fields_bytes = sz->count_array(fields()));
3289 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes()));
3290 sz->_ro_bytes += n;
3291
3292 const ConstantPool* cp = constants();
3293 if (cp) {
3294 cp->collect_statistics(sz);
3295 }
3296
3297 const Annotations* anno = annotations();
3298 if (anno) {
3299 anno->collect_statistics(sz);
3300 }
3301
3302 const Array<Method*>* methods_array = methods();
3303 if (methods()) {
3304 for (int i = 0; i < methods_array->length(); i++) {
3305 Method* method = methods_array->at(i);
3306 if (method) {
3307 sz->_method_count ++;
3308 method->collect_statistics(sz);
3309 }
3310 }
3311 }
3312 }
3313 #endif // INCLUDE_SERVICES
3314
3315 // Verification
3316
3317 class VerifyFieldClosure: public OopClosure {
3318 protected:
3319 template <class T> void do_oop_work(T* p) {
3320 oop obj = oopDesc::load_decode_heap_oop(p);
3321 if (!obj->is_oop_or_null()) {
3322 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3323 Universe::print_on(tty);
3324 guarantee(false, "boom");
3325 }
3326 }
3327 public:
3328 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3329 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3330 };
3331
3332 void InstanceKlass::verify_on(outputStream* st) {
3333 #ifndef PRODUCT
3334 // Avoid redundant verifies, this really should be in product.
3335 if (_verify_count == Universe::verify_count()) return;
3336 _verify_count = Universe::verify_count();
3337 #endif
3338
3339 // Verify Klass
3340 Klass::verify_on(st);
3341
3342 // Verify that klass is present in ClassLoaderData
3343 guarantee(class_loader_data()->contains_klass(this),
3344 "this class isn't found in class loader data");
3345
3346 // Verify vtables
3347 if (is_linked()) {
3348 // $$$ This used to be done only for m/s collections. Doing it
3349 // always seemed a valid generalization. (DLD -- 6/00)
3350 vtable().verify(st);
3351 }
3352
3353 // Verify first subklass
3354 if (subklass() != NULL) {
3355 guarantee(subklass()->is_klass(), "should be klass");
3356 }
3357
3358 // Verify siblings
3359 Klass* super = this->super();
3360 Klass* sib = next_sibling();
3361 if (sib != NULL) {
3362 if (sib == this) {
3363 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3364 }
3365
3366 guarantee(sib->is_klass(), "should be klass");
3367 guarantee(sib->super() == super, "siblings should have same superklass");
3368 }
3369
3370 // Verify implementor fields
3371 Klass* im = implementor();
3372 if (im != NULL) {
3373 guarantee(is_interface(), "only interfaces should have implementor set");
3374 guarantee(im->is_klass(), "should be klass");
3375 guarantee(!im->is_interface() || im == this,
3376 "implementors cannot be interfaces");
3377 }
3378
3379 // Verify local interfaces
3380 if (local_interfaces()) {
3381 Array<Klass*>* local_interfaces = this->local_interfaces();
3382 for (int j = 0; j < local_interfaces->length(); j++) {
3383 Klass* e = local_interfaces->at(j);
3384 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3385 }
3386 }
3387
3388 // Verify transitive interfaces
3389 if (transitive_interfaces() != NULL) {
3390 Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3391 for (int j = 0; j < transitive_interfaces->length(); j++) {
3392 Klass* e = transitive_interfaces->at(j);
3393 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3394 }
3395 }
3396
3397 // Verify methods
3398 if (methods() != NULL) {
3399 Array<Method*>* methods = this->methods();
3400 for (int j = 0; j < methods->length(); j++) {
3401 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3402 }
3403 for (int j = 0; j < methods->length() - 1; j++) {
3404 Method* m1 = methods->at(j);
3405 Method* m2 = methods->at(j + 1);
3406 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3407 }
3408 }
3409
3410 // Verify method ordering
3411 if (method_ordering() != NULL) {
3412 Array<int>* method_ordering = this->method_ordering();
3413 int length = method_ordering->length();
3414 if (JvmtiExport::can_maintain_original_method_order() ||
3415 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3416 guarantee(length == methods()->length(), "invalid method ordering length");
3417 jlong sum = 0;
3418 for (int j = 0; j < length; j++) {
3419 int original_index = method_ordering->at(j);
3420 guarantee(original_index >= 0, "invalid method ordering index");
3421 guarantee(original_index < length, "invalid method ordering index");
3422 sum += original_index;
3423 }
3424 // Verify sum of indices 0,1,...,length-1
3425 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3426 } else {
3427 guarantee(length == 0, "invalid method ordering length");
3428 }
3429 }
3430
3431 // Verify default methods
3432 if (default_methods() != NULL) {
3433 Array<Method*>* methods = this->default_methods();
3434 for (int j = 0; j < methods->length(); j++) {
3435 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3436 }
3437 for (int j = 0; j < methods->length() - 1; j++) {
3438 Method* m1 = methods->at(j);
3439 Method* m2 = methods->at(j + 1);
3440 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3441 }
3442 }
3443
3444 // Verify JNI static field identifiers
3445 if (jni_ids() != NULL) {
3446 jni_ids()->verify(this);
3447 }
3448
3449 // Verify other fields
3450 if (array_klasses() != NULL) {
3451 guarantee(array_klasses()->is_klass(), "should be klass");
3452 }
3453 if (constants() != NULL) {
3454 guarantee(constants()->is_constantPool(), "should be constant pool");
3455 }
3456 const Klass* host = host_klass();
3457 if (host != NULL) {
3458 guarantee(host->is_klass(), "should be klass");
3459 }
3460 }
3461
3462 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3463 Klass::oop_verify_on(obj, st);
3464 VerifyFieldClosure blk;
3465 obj->oop_iterate_no_header(&blk);
3466 }
3467
3468
3469 // JNIid class for jfieldIDs only
3470 // Note to reviewers:
3471 // These JNI functions are just moved over to column 1 and not changed
3472 // in the compressed oops workspace.
3473 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3474 _holder = holder;
3475 _offset = offset;
3476 _next = next;
3477 debug_only(_is_static_field_id = false;)
3478 }
3479
3480
3481 JNIid* JNIid::find(int offset) {
3482 JNIid* current = this;
3483 while (current != NULL) {
3484 if (current->offset() == offset) return current;
3485 current = current->next();
3486 }
3487 return NULL;
3488 }
3489
3490 void JNIid::deallocate(JNIid* current) {
3491 while (current != NULL) {
3492 JNIid* next = current->next();
3493 delete current;
3494 current = next;
3495 }
3496 }
3497
3498
3499 void JNIid::verify(Klass* holder) {
3500 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3501 int end_field_offset;
3502 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3503
3504 JNIid* current = this;
3505 while (current != NULL) {
3506 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3507 #ifdef ASSERT
3508 int o = current->offset();
3509 if (current->is_static_field_id()) {
3510 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3511 }
3512 #endif
3513 current = current->next();
3514 }
3515 }
3516
3517
3518 #ifdef ASSERT
3519 void InstanceKlass::set_init_state(ClassState state) {
3520 bool good_state = is_shared() ? (_init_state <= state)
3521 : (_init_state < state);
3522 assert(good_state || state == allocated, "illegal state transition");
3523 _init_state = (u1)state;
3524 }
3525 #endif
3526
3527 #if INCLUDE_JVMTI
3528
3529 // RedefineClasses() support for previous versions
3530
3531 // Globally, there is at least one previous version of a class to walk
3532 // during class unloading, which is saved because old methods in the class
3533 // are still running. Otherwise the previous version list is cleaned up.
3534 bool InstanceKlass::_has_previous_versions = false;
3535
3536 // Returns true if there are previous versions of a class for class
3537 // unloading only. Also resets the flag to false. purge_previous_version
3538 // will set the flag to true if there are any left, i.e., if there's any
3539 // work to do for next time. This is to avoid the expensive code cache
3540 // walk in CLDG::do_unloading().
3541 bool InstanceKlass::has_previous_versions_and_reset() {
3542 bool ret = _has_previous_versions;
3543 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3544 ret ? "true" : "false");
3545 _has_previous_versions = false;
3546 return ret;
3547 }
3548
3549 // Purge previous versions before adding new previous versions of the class and
3550 // during class unloading.
3551 void InstanceKlass::purge_previous_version_list() {
3552 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3553 assert(has_been_redefined(), "Should only be called for main class");
3554
3555 // Quick exit.
3556 if (previous_versions() == NULL) {
3557 return;
3558 }
3559
3560 // This klass has previous versions so see what we can cleanup
3561 // while it is safe to do so.
3562
3563 int deleted_count = 0; // leave debugging breadcrumbs
3564 int live_count = 0;
3565 ClassLoaderData* loader_data = class_loader_data();
3566 assert(loader_data != NULL, "should never be null");
3567
3568 ResourceMark rm;
3569 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3570
3571 // previous versions are linked together through the InstanceKlass
3572 InstanceKlass* pv_node = previous_versions();
3573 InstanceKlass* last = this;
3574 int version = 0;
3575
3576 // check the previous versions list
3577 for (; pv_node != NULL; ) {
3578
3579 ConstantPool* pvcp = pv_node->constants();
3580 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3581
3582 if (!pvcp->on_stack()) {
3583 // If the constant pool isn't on stack, none of the methods
3584 // are executing. Unlink this previous_version.
3585 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3586 // so will be deallocated during the next phase of class unloading.
3587 log_trace(redefine, class, iklass, purge)
3588 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3589 // For debugging purposes.
3590 pv_node->set_is_scratch_class();
3591 // Unlink from previous version list.
3592 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3593 InstanceKlass* next = pv_node->previous_versions();
3594 pv_node->link_previous_versions(NULL); // point next to NULL
3595 last->link_previous_versions(next);
3596 // Add to the deallocate list after unlinking
3597 loader_data->add_to_deallocate_list(pv_node);
3598 pv_node = next;
3599 deleted_count++;
3600 version++;
3601 continue;
3602 } else {
3603 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3604 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3605 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3606 live_count++;
3607 // found a previous version for next time we do class unloading
3608 _has_previous_versions = true;
3609 }
3610
3611 // At least one method is live in this previous version.
3612 // Reset dead EMCP methods not to get breakpoints.
3613 // All methods are deallocated when all of the methods for this class are no
3614 // longer running.
3615 Array<Method*>* method_refs = pv_node->methods();
3616 if (method_refs != NULL) {
3617 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3618 for (int j = 0; j < method_refs->length(); j++) {
3619 Method* method = method_refs->at(j);
3620
3621 if (!method->on_stack()) {
3622 // no breakpoints for non-running methods
3623 if (method->is_running_emcp()) {
3624 method->set_running_emcp(false);
3625 }
3626 } else {
3627 assert (method->is_obsolete() || method->is_running_emcp(),
3628 "emcp method cannot run after emcp bit is cleared");
3629 log_trace(redefine, class, iklass, purge)
3630 ("purge: %s(%s): prev method @%d in version @%d is alive",
3631 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3632 }
3633 }
3634 }
3635 // next previous version
3636 last = pv_node;
3637 pv_node = pv_node->previous_versions();
3638 version++;
3639 }
3640 log_trace(redefine, class, iklass, purge)
3641 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3642 }
3643
3644 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3645 int emcp_method_count) {
3646 int obsolete_method_count = old_methods->length() - emcp_method_count;
3647
3648 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3649 _previous_versions != NULL) {
3650 // We have a mix of obsolete and EMCP methods so we have to
3651 // clear out any matching EMCP method entries the hard way.
3652 int local_count = 0;
3653 for (int i = 0; i < old_methods->length(); i++) {
3654 Method* old_method = old_methods->at(i);
3655 if (old_method->is_obsolete()) {
3656 // only obsolete methods are interesting
3657 Symbol* m_name = old_method->name();
3658 Symbol* m_signature = old_method->signature();
3659
3660 // previous versions are linked together through the InstanceKlass
3661 int j = 0;
3662 for (InstanceKlass* prev_version = _previous_versions;
3663 prev_version != NULL;
3664 prev_version = prev_version->previous_versions(), j++) {
3665
3666 Array<Method*>* method_refs = prev_version->methods();
3667 for (int k = 0; k < method_refs->length(); k++) {
3668 Method* method = method_refs->at(k);
3669
3670 if (!method->is_obsolete() &&
3671 method->name() == m_name &&
3672 method->signature() == m_signature) {
3673 // The current RedefineClasses() call has made all EMCP
3674 // versions of this method obsolete so mark it as obsolete
3675 log_trace(redefine, class, iklass, add)
3676 ("%s(%s): flush obsolete method @%d in version @%d",
3677 m_name->as_C_string(), m_signature->as_C_string(), k, j);
3678
3679 method->set_is_obsolete();
3680 break;
3681 }
3682 }
3683
3684 // The previous loop may not find a matching EMCP method, but
3685 // that doesn't mean that we can optimize and not go any
3686 // further back in the PreviousVersion generations. The EMCP
3687 // method for this generation could have already been made obsolete,
3688 // but there still may be an older EMCP method that has not
3689 // been made obsolete.
3690 }
3691
3692 if (++local_count >= obsolete_method_count) {
3693 // no more obsolete methods so bail out now
3694 break;
3695 }
3696 }
3697 }
3698 }
3699 }
3700
3701 // Save the scratch_class as the previous version if any of the methods are running.
3702 // The previous_versions are used to set breakpoints in EMCP methods and they are
3703 // also used to clean MethodData links to redefined methods that are no longer running.
3704 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3705 int emcp_method_count) {
3706 assert(Thread::current()->is_VM_thread(),
3707 "only VMThread can add previous versions");
3708
3709 ResourceMark rm;
3710 log_trace(redefine, class, iklass, add)
3711 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3712
3713 // Clean out old previous versions for this class
3714 purge_previous_version_list();
3715
3716 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
3717 // a previous redefinition may be made obsolete by this redefinition.
3718 Array<Method*>* old_methods = scratch_class->methods();
3719 mark_newly_obsolete_methods(old_methods, emcp_method_count);
3720
3721 // If the constant pool for this previous version of the class
3722 // is not marked as being on the stack, then none of the methods
3723 // in this previous version of the class are on the stack so
3724 // we don't need to add this as a previous version.
3725 ConstantPool* cp_ref = scratch_class->constants();
3726 if (!cp_ref->on_stack()) {
3727 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3728 // For debugging purposes.
3729 scratch_class->set_is_scratch_class();
3730 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3731 return;
3732 }
3733
3734 if (emcp_method_count != 0) {
3735 // At least one method is still running, check for EMCP methods
3736 for (int i = 0; i < old_methods->length(); i++) {
3737 Method* old_method = old_methods->at(i);
3738 if (!old_method->is_obsolete() && old_method->on_stack()) {
3739 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3740 // we can add breakpoints for it.
3741
3742 // We set the method->on_stack bit during safepoints for class redefinition
3743 // and use this bit to set the is_running_emcp bit.
3744 // After the safepoint, the on_stack bit is cleared and the running emcp
3745 // method may exit. If so, we would set a breakpoint in a method that
3746 // is never reached, but this won't be noticeable to the programmer.
3747 old_method->set_running_emcp(true);
3748 log_trace(redefine, class, iklass, add)
3749 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3750 } else if (!old_method->is_obsolete()) {
3751 log_trace(redefine, class, iklass, add)
3752 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3753 }
3754 }
3755 }
3756
3757 // Add previous version if any methods are still running.
3758 // Set has_previous_version flag for processing during class unloading.
3759 _has_previous_versions = true;
3760 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3761 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3762 scratch_class->link_previous_versions(previous_versions());
3763 link_previous_versions(scratch_class);
3764 } // end add_previous_version()
3765
3766 #endif // INCLUDE_JVMTI
3767
3768 Method* InstanceKlass::method_with_idnum(int idnum) {
3769 Method* m = NULL;
3770 if (idnum < methods()->length()) {
3771 m = methods()->at(idnum);
3772 }
3773 if (m == NULL || m->method_idnum() != idnum) {
3774 for (int index = 0; index < methods()->length(); ++index) {
3775 m = methods()->at(index);
3776 if (m->method_idnum() == idnum) {
3777 return m;
3778 }
3779 }
3780 // None found, return null for the caller to handle.
3781 return NULL;
3782 }
3783 return m;
3784 }
3785
3786
3787 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3788 if (idnum >= methods()->length()) {
3789 return NULL;
3790 }
3791 Method* m = methods()->at(idnum);
3792 if (m != NULL && m->orig_method_idnum() == idnum) {
3793 return m;
3794 }
3795 // Obsolete method idnum does not match the original idnum
3796 for (int index = 0; index < methods()->length(); ++index) {
3797 m = methods()->at(index);
3798 if (m->orig_method_idnum() == idnum) {
3799 return m;
3800 }
3801 }
3802 // None found, return null for the caller to handle.
3803 return NULL;
3804 }
3805
3806
3807 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3808 InstanceKlass* holder = get_klass_version(version);
3809 if (holder == NULL) {
3810 return NULL; // The version of klass is gone, no method is found
3811 }
3812 Method* method = holder->method_with_orig_idnum(idnum);
3813 return method;
3814 }
3815
3816 #if INCLUDE_JVMTI
3817 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3818 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3819 // Ignore the archived class stream data
3820 return NULL;
3821 } else {
3822 return _cached_class_file;
3823 }
3824 }
3825
3826 jint InstanceKlass::get_cached_class_file_len() {
3827 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3828 }
3829
3830 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3831 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3832 }
3833
3834 #if INCLUDE_CDS
3835 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3836 assert(this->is_shared(), "class should be shared");
3837 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3838 return _cached_class_file;
3839 } else {
3840 return NULL;
3841 }
3842 }
3843 #endif
3844 #endif
3845
3846 #define THROW_DVT_ERROR(s) \
3847 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_InternalError(), \
3848 "DeriveValueType class '%s' %s", external_name(),(s)); \
3849 return
3850
3851 void InstanceKlass::create_derive_value_type(Handle class_loader, Handle protection_domain, TRAPS) {
3852 ResourceMark rm(THREAD);
3853 HandleMark hm(THREAD);
3854
3855 if (!EnableMVT) {
3856 return; // Silent fail
3857 }
3858 // Validate VCC...
3859 if (!has_nonstatic_fields()) {
3860 THROW_DVT_ERROR("has no instance fields");
3861 }
3862 if (is_value()) {
3863 THROW_DVT_ERROR("is already a value type");
3864 }
3865 if (!access_flags().is_final()) {
3866 THROW_DVT_ERROR("is not a final class");
3867 }
3868 if (super() != SystemDictionary::Object_klass()) {
3869 THROW_DVT_ERROR("does not derive from Object only");
3870 }
3871
3872 // All non-static are final
3873 GrowableArray<Handle>* fields = new GrowableArray<Handle>(THREAD, java_fields_count()*2);
3874 GrowableArray<jint>* fields_access = new GrowableArray<jint>(THREAD, java_fields_count()*2);
3875 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
3876 AccessFlags access_flags = fs.access_flags();
3877 if (access_flags.is_static()) {
3878 continue;
3879 }
3880 if (!access_flags.is_final()) {
3881 THROW_DVT_ERROR("contains non-final instance field");
3882 }
3883 jint flags = access_flags.get_flags();
3884 // Remember the field name, signature, access modifiers
3885 Handle h = java_lang_String::create_from_symbol(fs.name(), CHECK);
3886 fields->append(h);
3887 h = java_lang_String::create_from_symbol(fs.signature(), CHECK);
3888 fields->append(h);
3889 fields_access->append(access_flags.get_flags());
3890 }
3891
3892 // Generate DVT...
3893 log_debug(load)("Cooking DVT for VCC %s", external_name());
3894 const char* this_name = name()->as_C_string();
3895
3896 // Assemble the Java args...field descriptor array
3897 objArrayOop fdarr_oop = oopFactory::new_objectArray(fields->length(), CHECK);
3898 objArrayHandle fdarr(THREAD, fdarr_oop);
3899 for (int i = 0; i < fields->length(); i++) {
3900 fdarr->obj_at_put(i, fields->at(i)());
3901 }
3902 //...field access modifiers array
3903 typeArrayOop faarr_oop = oopFactory::new_intArray(fields_access->length(), CHECK);
3904 typeArrayHandle faarr(THREAD, faarr_oop);
3905 for (int i = 0; i < fields_access->length(); i++) {
3906 faarr->int_at_put(i, fields_access->at(i));
3907 }
3908
3909 Handle vcc_name_h = java_lang_String::create_from_symbol(name(), CHECK);
3910 // Upcall to our Java helper...
3911 JavaValue result(T_OBJECT);
3912 JavaCallArguments args(5);
3913 args.push_oop(vcc_name_h);
3914 args.push_oop(class_loader);
3915 args.push_oop(protection_domain);
3916 args.push_oop(fdarr);
3917 args.push_oop(faarr);
3918 JavaCalls::call_static(&result,
3919 SystemDictionary::Valhalla_MVT1_0_klass(),
3920 vmSymbols::valhalla_shady_MVT1_0_createDerivedValueType(),
3921 vmSymbols::valhalla_shady_MVT1_0_createDerivedValueType_signature(),
3922 &args,
3923 CHECK);
3924 Handle returned(THREAD, (oop) result.get_jobject());
3925 if (returned.is_null()) {
3926 THROW_DVT_ERROR("unknown error deriving value type");
3927 }
3928 TempNewSymbol dvt_name_sym = java_lang_String::as_symbol(returned(), CHECK);
3929
3930 Klass* dvt_klass = SystemDictionary::resolve_or_null(dvt_name_sym,
3931 class_loader,
3932 protection_domain,
3933 CHECK);
3934 if (!dvt_klass->is_value()) {
3935 THROW_DVT_ERROR("failed to resolve derived value type");
3936 }
3937 /**
3938 * Found it, let's point to each other to denote "is_derive_vt()"...
3939 */
3940 ValueKlass* vt_klass = ValueKlass::cast(dvt_klass);
3941 assert(vt_klass->class_loader() == class_loader(), "DVT Not the same class loader as VCC");
3942 vt_klass->set_vcc_klass(this);
3943 log_debug(load)("Cooked DVT %s for VCC %s", vt_klass->external_name(), external_name());
3944 }
3945