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