instanceKlass.cpp revision 9727:f944761a3ce3
1/*
2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled.hpp"
26#include "classfile/classFileParser.hpp"
27#include "classfile/javaClasses.hpp"
28#include "classfile/systemDictionary.hpp"
29#include "classfile/verifier.hpp"
30#include "classfile/vmSymbols.hpp"
31#include "code/dependencyContext.hpp"
32#include "compiler/compileBroker.hpp"
33#include "gc/shared/collectedHeap.inline.hpp"
34#include "gc/shared/specialized_oop_closures.hpp"
35#include "interpreter/oopMapCache.hpp"
36#include "interpreter/rewriter.hpp"
37#include "jvmtifiles/jvmti.h"
38#include "memory/heapInspection.hpp"
39#include "memory/iterator.inline.hpp"
40#include "memory/metadataFactory.hpp"
41#include "memory/oopFactory.hpp"
42#include "oops/fieldStreams.hpp"
43#include "oops/instanceClassLoaderKlass.hpp"
44#include "oops/instanceKlass.inline.hpp"
45#include "oops/instanceMirrorKlass.hpp"
46#include "oops/instanceOop.hpp"
47#include "oops/klass.inline.hpp"
48#include "oops/method.hpp"
49#include "oops/oop.inline.hpp"
50#include "oops/symbol.hpp"
51#include "prims/jvmtiExport.hpp"
52#include "prims/jvmtiRedefineClasses.hpp"
53#include "prims/jvmtiRedefineClassesTrace.hpp"
54#include "prims/jvmtiThreadState.hpp"
55#include "prims/methodComparator.hpp"
56#include "runtime/atomic.inline.hpp"
57#include "runtime/fieldDescriptor.hpp"
58#include "runtime/handles.inline.hpp"
59#include "runtime/javaCalls.hpp"
60#include "runtime/mutexLocker.hpp"
61#include "runtime/orderAccess.inline.hpp"
62#include "runtime/thread.inline.hpp"
63#include "services/classLoadingService.hpp"
64#include "services/threadService.hpp"
65#include "utilities/dtrace.hpp"
66#include "utilities/macros.hpp"
67#include "logging/log.hpp"
68#ifdef COMPILER1
69#include "c1/c1_Compiler.hpp"
70#endif
71
72#ifdef DTRACE_ENABLED
73
74
75#define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
76#define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
77#define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
78#define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
79#define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
80#define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
81#define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
82#define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
83#define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)          \
84  {                                                              \
85    char* data = NULL;                                           \
86    int len = 0;                                                 \
87    Symbol* name = (clss)->name();                               \
88    if (name != NULL) {                                          \
89      data = (char*)name->bytes();                               \
90      len = name->utf8_length();                                 \
91    }                                                            \
92    HOTSPOT_CLASS_INITIALIZATION_##type(                         \
93      data, len, (clss)->class_loader(), thread_type);           \
94  }
95
96#define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
97  {                                                              \
98    char* data = NULL;                                           \
99    int len = 0;                                                 \
100    Symbol* name = (clss)->name();                               \
101    if (name != NULL) {                                          \
102      data = (char*)name->bytes();                               \
103      len = name->utf8_length();                                 \
104    }                                                            \
105    HOTSPOT_CLASS_INITIALIZATION_##type(                         \
106      data, len, (clss)->class_loader(), thread_type, wait);     \
107  }
108
109#else //  ndef DTRACE_ENABLED
110
111#define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
112#define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
113
114#endif //  ndef DTRACE_ENABLED
115
116volatile int InstanceKlass::_total_instanceKlass_count = 0;
117
118static inline bool is_class_loader(const Symbol* class_name,
119                                   const ClassFileParser& parser) {
120  assert(class_name != NULL, "invariant");
121
122  if (class_name == vmSymbols::java_lang_ClassLoader()) {
123    return true;
124  }
125
126  if (SystemDictionary::ClassLoader_klass_loaded()) {
127    const Klass* const super_klass = parser.super_klass();
128    if (super_klass != NULL) {
129      if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
130        return true;
131      }
132    }
133  }
134  return false;
135}
136
137InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
138  const int size = InstanceKlass::size(parser.vtable_size(),
139                                       parser.itable_size(),
140                                       nonstatic_oop_map_size(parser.total_oop_map_count()),
141                                       parser.is_interface(),
142                                       parser.is_anonymous());
143
144  const Symbol* const class_name = parser.class_name();
145  assert(class_name != NULL, "invariant");
146  ClassLoaderData* loader_data = parser.loader_data();
147  assert(loader_data != NULL, "invariant");
148
149  InstanceKlass* ik;
150
151  // Allocation
152  if (REF_NONE == parser.reference_type()) {
153    if (class_name == vmSymbols::java_lang_Class()) {
154      // mirror
155      ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
156    }
157    else if (is_class_loader(class_name, parser)) {
158      // class loader
159      ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
160    }
161    else {
162      // normal
163      ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
164    }
165  }
166  else {
167    // reference
168    ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
169  }
170
171  // Check for pending exception before adding to the loader data and incrementing
172  // class count.  Can get OOM here.
173  if (HAS_PENDING_EXCEPTION) {
174    return NULL;
175  }
176
177  assert(ik != NULL, "invariant");
178
179  const bool publicize = !parser.is_internal();
180
181  // Add all classes to our internal class loader list here,
182  // including classes in the bootstrap (NULL) class loader.
183  loader_data->add_class(ik, publicize);
184  Atomic::inc(&_total_instanceKlass_count);
185
186  return ik;
187}
188
189
190// copy method ordering from resource area to Metaspace
191void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
192  if (m != NULL) {
193    // allocate a new array and copy contents (memcpy?)
194    _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
195    for (int i = 0; i < m->length(); i++) {
196      _method_ordering->at_put(i, m->at(i));
197    }
198  } else {
199    _method_ordering = Universe::the_empty_int_array();
200  }
201}
202
203// create a new array of vtable_indices for default methods
204Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
205  Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
206  assert(default_vtable_indices() == NULL, "only create once");
207  set_default_vtable_indices(vtable_indices);
208  return vtable_indices;
209}
210
211InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
212  _static_field_size(parser.static_field_size()),
213  _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
214  _vtable_len(parser.vtable_size()),
215  _itable_len(parser.itable_size()),
216  _reference_type(parser.reference_type()) {
217    set_kind(kind);
218    set_access_flags(parser.access_flags());
219    set_is_anonymous(parser.is_anonymous());
220    set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
221                                                    false));
222
223    assert(NULL == _methods, "underlying memory not zeroed?");
224    assert(is_instance_klass(), "is layout incorrect?");
225    assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
226}
227
228void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
229                                       Array<Method*>* methods) {
230  if (methods != NULL && methods != Universe::the_empty_method_array() &&
231      !methods->is_shared()) {
232    for (int i = 0; i < methods->length(); i++) {
233      Method* method = methods->at(i);
234      if (method == NULL) continue;  // maybe null if error processing
235      // Only want to delete methods that are not executing for RedefineClasses.
236      // The previous version will point to them so they're not totally dangling
237      assert (!method->on_stack(), "shouldn't be called with methods on stack");
238      MetadataFactory::free_metadata(loader_data, method);
239    }
240    MetadataFactory::free_array<Method*>(loader_data, methods);
241  }
242}
243
244void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
245                                          const Klass* super_klass,
246                                          Array<Klass*>* local_interfaces,
247                                          Array<Klass*>* transitive_interfaces) {
248  // Only deallocate transitive interfaces if not empty, same as super class
249  // or same as local interfaces.  See code in parseClassFile.
250  Array<Klass*>* ti = transitive_interfaces;
251  if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
252    // check that the interfaces don't come from super class
253    Array<Klass*>* sti = (super_klass == NULL) ? NULL :
254                    InstanceKlass::cast(super_klass)->transitive_interfaces();
255    if (ti != sti && ti != NULL && !ti->is_shared()) {
256      MetadataFactory::free_array<Klass*>(loader_data, ti);
257    }
258  }
259
260  // local interfaces can be empty
261  if (local_interfaces != Universe::the_empty_klass_array() &&
262      local_interfaces != NULL && !local_interfaces->is_shared()) {
263    MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
264  }
265}
266
267// This function deallocates the metadata and C heap pointers that the
268// InstanceKlass points to.
269void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
270
271  // Orphan the mirror first, CMS thinks it's still live.
272  if (java_mirror() != NULL) {
273    java_lang_Class::set_klass(java_mirror(), NULL);
274  }
275
276  // Need to take this class off the class loader data list.
277  loader_data->remove_class(this);
278
279  // The array_klass for this class is created later, after error handling.
280  // For class redefinition, we keep the original class so this scratch class
281  // doesn't have an array class.  Either way, assert that there is nothing
282  // to deallocate.
283  assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
284
285  // Release C heap allocated data that this might point to, which includes
286  // reference counting symbol names.
287  release_C_heap_structures();
288
289  deallocate_methods(loader_data, methods());
290  set_methods(NULL);
291
292  if (method_ordering() != NULL &&
293      method_ordering() != Universe::the_empty_int_array() &&
294      !method_ordering()->is_shared()) {
295    MetadataFactory::free_array<int>(loader_data, method_ordering());
296  }
297  set_method_ordering(NULL);
298
299  // default methods can be empty
300  if (default_methods() != NULL &&
301      default_methods() != Universe::the_empty_method_array() &&
302      !default_methods()->is_shared()) {
303    MetadataFactory::free_array<Method*>(loader_data, default_methods());
304  }
305  // Do NOT deallocate the default methods, they are owned by superinterfaces.
306  set_default_methods(NULL);
307
308  // default methods vtable indices can be empty
309  if (default_vtable_indices() != NULL &&
310      !default_vtable_indices()->is_shared()) {
311    MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
312  }
313  set_default_vtable_indices(NULL);
314
315
316  // This array is in Klass, but remove it with the InstanceKlass since
317  // this place would be the only caller and it can share memory with transitive
318  // interfaces.
319  if (secondary_supers() != NULL &&
320      secondary_supers() != Universe::the_empty_klass_array() &&
321      secondary_supers() != transitive_interfaces() &&
322      !secondary_supers()->is_shared()) {
323    MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
324  }
325  set_secondary_supers(NULL);
326
327  deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
328  set_transitive_interfaces(NULL);
329  set_local_interfaces(NULL);
330
331  if (fields() != NULL && !fields()->is_shared()) {
332    MetadataFactory::free_array<jushort>(loader_data, fields());
333  }
334  set_fields(NULL, 0);
335
336  // If a method from a redefined class is using this constant pool, don't
337  // delete it, yet.  The new class's previous version will point to this.
338  if (constants() != NULL) {
339    assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
340    if (!constants()->is_shared()) {
341      MetadataFactory::free_metadata(loader_data, constants());
342    }
343    // Delete any cached resolution errors for the constant pool
344    SystemDictionary::delete_resolution_error(constants());
345
346    set_constants(NULL);
347  }
348
349  if (inner_classes() != NULL &&
350      inner_classes() != Universe::the_empty_short_array() &&
351      !inner_classes()->is_shared()) {
352    MetadataFactory::free_array<jushort>(loader_data, inner_classes());
353  }
354  set_inner_classes(NULL);
355
356  // We should deallocate the Annotations instance if it's not in shared spaces.
357  if (annotations() != NULL && !annotations()->is_shared()) {
358    MetadataFactory::free_metadata(loader_data, annotations());
359  }
360  set_annotations(NULL);
361}
362
363bool InstanceKlass::should_be_initialized() const {
364  return !is_initialized();
365}
366
367klassVtable* InstanceKlass::vtable() const {
368  return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
369}
370
371klassItable* InstanceKlass::itable() const {
372  return new klassItable(instanceKlassHandle(this));
373}
374
375void InstanceKlass::eager_initialize(Thread *thread) {
376  if (!EagerInitialization) return;
377
378  if (this->is_not_initialized()) {
379    // abort if the the class has a class initializer
380    if (this->class_initializer() != NULL) return;
381
382    // abort if it is java.lang.Object (initialization is handled in genesis)
383    Klass* super = this->super();
384    if (super == NULL) return;
385
386    // abort if the super class should be initialized
387    if (!InstanceKlass::cast(super)->is_initialized()) return;
388
389    // call body to expose the this pointer
390    instanceKlassHandle this_k(thread, this);
391    eager_initialize_impl(this_k);
392  }
393}
394
395// JVMTI spec thinks there are signers and protection domain in the
396// instanceKlass.  These accessors pretend these fields are there.
397// The hprof specification also thinks these fields are in InstanceKlass.
398oop InstanceKlass::protection_domain() const {
399  // return the protection_domain from the mirror
400  return java_lang_Class::protection_domain(java_mirror());
401}
402
403// To remove these from requires an incompatible change and CCC request.
404objArrayOop InstanceKlass::signers() const {
405  // return the signers from the mirror
406  return java_lang_Class::signers(java_mirror());
407}
408
409oop InstanceKlass::init_lock() const {
410  // return the init lock from the mirror
411  oop lock = java_lang_Class::init_lock(java_mirror());
412  // Prevent reordering with any access of initialization state
413  OrderAccess::loadload();
414  assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
415         "only fully initialized state can have a null lock");
416  return lock;
417}
418
419// Set the initialization lock to null so the object can be GC'ed.  Any racing
420// threads to get this lock will see a null lock and will not lock.
421// That's okay because they all check for initialized state after getting
422// the lock and return.
423void InstanceKlass::fence_and_clear_init_lock() {
424  // make sure previous stores are all done, notably the init_state.
425  OrderAccess::storestore();
426  java_lang_Class::set_init_lock(java_mirror(), NULL);
427  assert(!is_not_initialized(), "class must be initialized now");
428}
429
430void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
431  EXCEPTION_MARK;
432  oop init_lock = this_k->init_lock();
433  ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
434
435  // abort if someone beat us to the initialization
436  if (!this_k->is_not_initialized()) return;  // note: not equivalent to is_initialized()
437
438  ClassState old_state = this_k->init_state();
439  link_class_impl(this_k, true, THREAD);
440  if (HAS_PENDING_EXCEPTION) {
441    CLEAR_PENDING_EXCEPTION;
442    // Abort if linking the class throws an exception.
443
444    // Use a test to avoid redundantly resetting the state if there's
445    // no change.  Set_init_state() asserts that state changes make
446    // progress, whereas here we might just be spinning in place.
447    if( old_state != this_k->_init_state )
448      this_k->set_init_state (old_state);
449  } else {
450    // linking successfull, mark class as initialized
451    this_k->set_init_state (fully_initialized);
452    this_k->fence_and_clear_init_lock();
453    // trace
454    if (log_is_enabled(Info, classinit)) {
455      ResourceMark rm(THREAD);
456      log_info(classinit)("[Initialized %s without side effects]", this_k->external_name());
457    }
458  }
459}
460
461
462// See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
463// process. The step comments refers to the procedure described in that section.
464// Note: implementation moved to static method to expose the this pointer.
465void InstanceKlass::initialize(TRAPS) {
466  if (this->should_be_initialized()) {
467    HandleMark hm(THREAD);
468    instanceKlassHandle this_k(THREAD, this);
469    initialize_impl(this_k, CHECK);
470    // Note: at this point the class may be initialized
471    //       OR it may be in the state of being initialized
472    //       in case of recursive initialization!
473  } else {
474    assert(is_initialized(), "sanity check");
475  }
476}
477
478
479bool InstanceKlass::verify_code(
480    instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
481  // 1) Verify the bytecodes
482  Verifier::Mode mode =
483    throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
484  return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD);
485}
486
487
488// Used exclusively by the shared spaces dump mechanism to prevent
489// classes mapped into the shared regions in new VMs from appearing linked.
490
491void InstanceKlass::unlink_class() {
492  assert(is_linked(), "must be linked");
493  _init_state = loaded;
494}
495
496void InstanceKlass::link_class(TRAPS) {
497  assert(is_loaded(), "must be loaded");
498  if (!is_linked()) {
499    HandleMark hm(THREAD);
500    instanceKlassHandle this_k(THREAD, this);
501    link_class_impl(this_k, true, CHECK);
502  }
503}
504
505// Called to verify that a class can link during initialization, without
506// throwing a VerifyError.
507bool InstanceKlass::link_class_or_fail(TRAPS) {
508  assert(is_loaded(), "must be loaded");
509  if (!is_linked()) {
510    HandleMark hm(THREAD);
511    instanceKlassHandle this_k(THREAD, this);
512    link_class_impl(this_k, false, CHECK_false);
513  }
514  return is_linked();
515}
516
517bool InstanceKlass::link_class_impl(
518    instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
519  // check for error state
520  if (this_k->is_in_error_state()) {
521    ResourceMark rm(THREAD);
522    THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
523               this_k->external_name(), false);
524  }
525  // return if already verified
526  if (this_k->is_linked()) {
527    return true;
528  }
529
530  // Timing
531  // timer handles recursion
532  assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
533  JavaThread* jt = (JavaThread*)THREAD;
534
535  // link super class before linking this class
536  instanceKlassHandle super(THREAD, this_k->super());
537  if (super.not_null()) {
538    if (super->is_interface()) {  // check if super class is an interface
539      ResourceMark rm(THREAD);
540      Exceptions::fthrow(
541        THREAD_AND_LOCATION,
542        vmSymbols::java_lang_IncompatibleClassChangeError(),
543        "class %s has interface %s as super class",
544        this_k->external_name(),
545        super->external_name()
546      );
547      return false;
548    }
549
550    link_class_impl(super, throw_verifyerror, CHECK_false);
551  }
552
553  // link all interfaces implemented by this class before linking this class
554  Array<Klass*>* interfaces = this_k->local_interfaces();
555  int num_interfaces = interfaces->length();
556  for (int index = 0; index < num_interfaces; index++) {
557    HandleMark hm(THREAD);
558    instanceKlassHandle ih(THREAD, interfaces->at(index));
559    link_class_impl(ih, throw_verifyerror, CHECK_false);
560  }
561
562  // in case the class is linked in the process of linking its superclasses
563  if (this_k->is_linked()) {
564    return true;
565  }
566
567  // trace only the link time for this klass that includes
568  // the verification time
569  PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
570                             ClassLoader::perf_class_link_selftime(),
571                             ClassLoader::perf_classes_linked(),
572                             jt->get_thread_stat()->perf_recursion_counts_addr(),
573                             jt->get_thread_stat()->perf_timers_addr(),
574                             PerfClassTraceTime::CLASS_LINK);
575
576  // verification & rewriting
577  {
578    oop init_lock = this_k->init_lock();
579    ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
580    // rewritten will have been set if loader constraint error found
581    // on an earlier link attempt
582    // don't verify or rewrite if already rewritten
583
584    if (!this_k->is_linked()) {
585      if (!this_k->is_rewritten()) {
586        {
587          bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
588          if (!verify_ok) {
589            return false;
590          }
591        }
592
593        // Just in case a side-effect of verify linked this class already
594        // (which can sometimes happen since the verifier loads classes
595        // using custom class loaders, which are free to initialize things)
596        if (this_k->is_linked()) {
597          return true;
598        }
599
600        // also sets rewritten
601        this_k->rewrite_class(CHECK_false);
602      }
603
604      // relocate jsrs and link methods after they are all rewritten
605      this_k->link_methods(CHECK_false);
606
607      // Initialize the vtable and interface table after
608      // methods have been rewritten since rewrite may
609      // fabricate new Method*s.
610      // also does loader constraint checking
611      if (!this_k()->is_shared()) {
612        ResourceMark rm(THREAD);
613        this_k->vtable()->initialize_vtable(true, CHECK_false);
614        this_k->itable()->initialize_itable(true, CHECK_false);
615      }
616#ifdef ASSERT
617      else {
618        ResourceMark rm(THREAD);
619        this_k->vtable()->verify(tty, true);
620        // In case itable verification is ever added.
621        // this_k->itable()->verify(tty, true);
622      }
623#endif
624      this_k->set_init_state(linked);
625      if (JvmtiExport::should_post_class_prepare()) {
626        Thread *thread = THREAD;
627        assert(thread->is_Java_thread(), "thread->is_Java_thread()");
628        JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
629      }
630    }
631  }
632  return true;
633}
634
635
636// Rewrite the byte codes of all of the methods of a class.
637// The rewriter must be called exactly once. Rewriting must happen after
638// verification but before the first method of the class is executed.
639void InstanceKlass::rewrite_class(TRAPS) {
640  assert(is_loaded(), "must be loaded");
641  instanceKlassHandle this_k(THREAD, this);
642  if (this_k->is_rewritten()) {
643    assert(this_k()->is_shared(), "rewriting an unshared class?");
644    return;
645  }
646  Rewriter::rewrite(this_k, CHECK);
647  this_k->set_rewritten();
648}
649
650// Now relocate and link method entry points after class is rewritten.
651// This is outside is_rewritten flag. In case of an exception, it can be
652// executed more than once.
653void InstanceKlass::link_methods(TRAPS) {
654  int len = methods()->length();
655  for (int i = len-1; i >= 0; i--) {
656    methodHandle m(THREAD, methods()->at(i));
657
658    // Set up method entry points for compiler and interpreter    .
659    m->link_method(m, CHECK);
660  }
661}
662
663// Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
664void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) {
665  if (this_k->has_default_methods()) {
666    for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
667      Klass* iface = this_k->local_interfaces()->at(i);
668      InstanceKlass* ik = InstanceKlass::cast(iface);
669      if (ik->should_be_initialized()) {
670        if (ik->has_default_methods()) {
671          ik->initialize_super_interfaces(ik, THREAD);
672        }
673        // Only initialize() interfaces that "declare" concrete methods.
674        // has_default_methods drives searching superinterfaces since it
675        // means has_default_methods in its superinterface hierarchy
676        if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) {
677          ik->initialize(THREAD);
678        }
679        if (HAS_PENDING_EXCEPTION) {
680          Handle e(THREAD, PENDING_EXCEPTION);
681          CLEAR_PENDING_EXCEPTION;
682          {
683            EXCEPTION_MARK;
684            // Locks object, set state, and notify all waiting threads
685            this_k->set_initialization_state_and_notify(
686                initialization_error, THREAD);
687
688            // ignore any exception thrown, superclass initialization error is
689            // thrown below
690            CLEAR_PENDING_EXCEPTION;
691          }
692          THROW_OOP(e());
693        }
694      }
695    }
696  }
697}
698
699void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
700  // Make sure klass is linked (verified) before initialization
701  // A class could already be verified, since it has been reflected upon.
702  this_k->link_class(CHECK);
703
704  DTRACE_CLASSINIT_PROBE(required, this_k(), -1);
705
706  bool wait = false;
707
708  // refer to the JVM book page 47 for description of steps
709  // Step 1
710  {
711    oop init_lock = this_k->init_lock();
712    ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
713
714    Thread *self = THREAD; // it's passed the current thread
715
716    // Step 2
717    // If we were to use wait() instead of waitInterruptibly() then
718    // we might end up throwing IE from link/symbol resolution sites
719    // that aren't expected to throw.  This would wreak havoc.  See 6320309.
720    while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
721        wait = true;
722      ol.waitUninterruptibly(CHECK);
723    }
724
725    // Step 3
726    if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
727      DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k(), -1,wait);
728      return;
729    }
730
731    // Step 4
732    if (this_k->is_initialized()) {
733      DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k(), -1,wait);
734      return;
735    }
736
737    // Step 5
738    if (this_k->is_in_error_state()) {
739      DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k(), -1,wait);
740      ResourceMark rm(THREAD);
741      const char* desc = "Could not initialize class ";
742      const char* className = this_k->external_name();
743      size_t msglen = strlen(desc) + strlen(className) + 1;
744      char* message = NEW_RESOURCE_ARRAY(char, msglen);
745      if (NULL == message) {
746        // Out of memory: can't create detailed error message
747        THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
748      } else {
749        jio_snprintf(message, msglen, "%s%s", desc, className);
750        THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
751      }
752    }
753
754    // Step 6
755    this_k->set_init_state(being_initialized);
756    this_k->set_init_thread(self);
757  }
758
759  // Step 7
760  Klass* super_klass = this_k->super();
761  if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) {
762    super_klass->initialize(THREAD);
763
764    if (HAS_PENDING_EXCEPTION) {
765      Handle e(THREAD, PENDING_EXCEPTION);
766      CLEAR_PENDING_EXCEPTION;
767      {
768        EXCEPTION_MARK;
769        this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
770        CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, superclass initialization error is thrown below
771      }
772      DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k(), -1,wait);
773      THROW_OOP(e());
774    }
775  }
776
777  // If C is an interface that declares a non-abstract, non-static method,
778  // the initialization of a class (not an interface) that implements C directly or
779  // indirectly.
780  // Recursively initialize any superinterfaces that declare default methods
781  // Only need to recurse if has_default_methods which includes declaring and
782  // inheriting default methods
783  if (!this_k->is_interface() && this_k->has_default_methods()) {
784    this_k->initialize_super_interfaces(this_k, CHECK);
785  }
786
787  // Step 8
788  {
789    assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
790    JavaThread* jt = (JavaThread*)THREAD;
791    DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k(), -1,wait);
792    // Timer includes any side effects of class initialization (resolution,
793    // etc), but not recursive entry into call_class_initializer().
794    PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
795                             ClassLoader::perf_class_init_selftime(),
796                             ClassLoader::perf_classes_inited(),
797                             jt->get_thread_stat()->perf_recursion_counts_addr(),
798                             jt->get_thread_stat()->perf_timers_addr(),
799                             PerfClassTraceTime::CLASS_CLINIT);
800    this_k->call_class_initializer(THREAD);
801  }
802
803  // Step 9
804  if (!HAS_PENDING_EXCEPTION) {
805    this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
806    { ResourceMark rm(THREAD);
807      debug_only(this_k->vtable()->verify(tty, true);)
808    }
809  }
810  else {
811    // Step 10 and 11
812    Handle e(THREAD, PENDING_EXCEPTION);
813    CLEAR_PENDING_EXCEPTION;
814    // JVMTI has already reported the pending exception
815    // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
816    JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
817    {
818      EXCEPTION_MARK;
819      this_k->set_initialization_state_and_notify(initialization_error, THREAD);
820      CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
821      // JVMTI has already reported the pending exception
822      // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
823      JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
824    }
825    DTRACE_CLASSINIT_PROBE_WAIT(error, this_k(), -1,wait);
826    if (e->is_a(SystemDictionary::Error_klass())) {
827      THROW_OOP(e());
828    } else {
829      JavaCallArguments args(e);
830      THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
831                vmSymbols::throwable_void_signature(),
832                &args);
833    }
834  }
835  DTRACE_CLASSINIT_PROBE_WAIT(end, this_k(), -1,wait);
836}
837
838
839// Note: implementation moved to static method to expose the this pointer.
840void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
841  instanceKlassHandle kh(THREAD, this);
842  set_initialization_state_and_notify_impl(kh, state, CHECK);
843}
844
845void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
846  oop init_lock = this_k->init_lock();
847  ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
848  this_k->set_init_state(state);
849  this_k->fence_and_clear_init_lock();
850  ol.notify_all(CHECK);
851}
852
853// The embedded _implementor field can only record one implementor.
854// When there are more than one implementors, the _implementor field
855// is set to the interface Klass* itself. Following are the possible
856// values for the _implementor field:
857//   NULL                  - no implementor
858//   implementor Klass*    - one implementor
859//   self                  - more than one implementor
860//
861// The _implementor field only exists for interfaces.
862void InstanceKlass::add_implementor(Klass* k) {
863  assert(Compile_lock->owned_by_self(), "");
864  assert(is_interface(), "not interface");
865  // Filter out my subinterfaces.
866  // (Note: Interfaces are never on the subklass list.)
867  if (InstanceKlass::cast(k)->is_interface()) return;
868
869  // Filter out subclasses whose supers already implement me.
870  // (Note: CHA must walk subclasses of direct implementors
871  // in order to locate indirect implementors.)
872  Klass* sk = k->super();
873  if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
874    // We only need to check one immediate superclass, since the
875    // implements_interface query looks at transitive_interfaces.
876    // Any supers of the super have the same (or fewer) transitive_interfaces.
877    return;
878
879  Klass* ik = implementor();
880  if (ik == NULL) {
881    set_implementor(k);
882  } else if (ik != this) {
883    // There is already an implementor. Use itself as an indicator of
884    // more than one implementors.
885    set_implementor(this);
886  }
887
888  // The implementor also implements the transitive_interfaces
889  for (int index = 0; index < local_interfaces()->length(); index++) {
890    InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
891  }
892}
893
894void InstanceKlass::init_implementor() {
895  if (is_interface()) {
896    set_implementor(NULL);
897  }
898}
899
900
901void InstanceKlass::process_interfaces(Thread *thread) {
902  // link this class into the implementors list of every interface it implements
903  for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
904    assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
905    InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
906    assert(interf->is_interface(), "expected interface");
907    interf->add_implementor(this);
908  }
909}
910
911bool InstanceKlass::can_be_primary_super_slow() const {
912  if (is_interface())
913    return false;
914  else
915    return Klass::can_be_primary_super_slow();
916}
917
918GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
919  // The secondaries are the implemented interfaces.
920  Array<Klass*>* interfaces = transitive_interfaces();
921  int num_secondaries = num_extra_slots + interfaces->length();
922  if (num_secondaries == 0) {
923    // Must share this for correct bootstrapping!
924    set_secondary_supers(Universe::the_empty_klass_array());
925    return NULL;
926  } else if (num_extra_slots == 0) {
927    // The secondary super list is exactly the same as the transitive interfaces.
928    // Redefine classes has to be careful not to delete this!
929    set_secondary_supers(interfaces);
930    return NULL;
931  } else {
932    // Copy transitive interfaces to a temporary growable array to be constructed
933    // into the secondary super list with extra slots.
934    GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
935    for (int i = 0; i < interfaces->length(); i++) {
936      secondaries->push(interfaces->at(i));
937    }
938    return secondaries;
939  }
940}
941
942bool InstanceKlass::compute_is_subtype_of(Klass* k) {
943  if (k->is_interface()) {
944    return implements_interface(k);
945  } else {
946    return Klass::compute_is_subtype_of(k);
947  }
948}
949
950bool InstanceKlass::implements_interface(Klass* k) const {
951  if (this == k) return true;
952  assert(k->is_interface(), "should be an interface class");
953  for (int i = 0; i < transitive_interfaces()->length(); i++) {
954    if (transitive_interfaces()->at(i) == k) {
955      return true;
956    }
957  }
958  return false;
959}
960
961bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
962  // Verify direct super interface
963  if (this == k) return true;
964  assert(k->is_interface(), "should be an interface class");
965  for (int i = 0; i < local_interfaces()->length(); i++) {
966    if (local_interfaces()->at(i) == k) {
967      return true;
968    }
969  }
970  return false;
971}
972
973objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
974  if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
975  if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
976    report_java_out_of_memory("Requested array size exceeds VM limit");
977    JvmtiExport::post_array_size_exhausted();
978    THROW_OOP_0(Universe::out_of_memory_error_array_size());
979  }
980  int size = objArrayOopDesc::object_size(length);
981  Klass* ak = array_klass(n, CHECK_NULL);
982  KlassHandle h_ak (THREAD, ak);
983  objArrayOop o =
984    (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
985  return o;
986}
987
988instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
989  if (TraceFinalizerRegistration) {
990    tty->print("Registered ");
991    i->print_value_on(tty);
992    tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
993  }
994  instanceHandle h_i(THREAD, i);
995  // Pass the handle as argument, JavaCalls::call expects oop as jobjects
996  JavaValue result(T_VOID);
997  JavaCallArguments args(h_i);
998  methodHandle mh (THREAD, Universe::finalizer_register_method());
999  JavaCalls::call(&result, mh, &args, CHECK_NULL);
1000  return h_i();
1001}
1002
1003instanceOop InstanceKlass::allocate_instance(TRAPS) {
1004  bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1005  int size = size_helper();  // Query before forming handle.
1006
1007  KlassHandle h_k(THREAD, this);
1008
1009  instanceOop i;
1010
1011  i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1012  if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1013    i = register_finalizer(i, CHECK_NULL);
1014  }
1015  return i;
1016}
1017
1018void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1019  if (is_interface() || is_abstract()) {
1020    ResourceMark rm(THREAD);
1021    THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1022              : vmSymbols::java_lang_InstantiationException(), external_name());
1023  }
1024  if (this == SystemDictionary::Class_klass()) {
1025    ResourceMark rm(THREAD);
1026    THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1027              : vmSymbols::java_lang_IllegalAccessException(), external_name());
1028  }
1029}
1030
1031Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1032  instanceKlassHandle this_k(THREAD, this);
1033  return array_klass_impl(this_k, or_null, n, THREAD);
1034}
1035
1036Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1037  if (this_k->array_klasses() == NULL) {
1038    if (or_null) return NULL;
1039
1040    ResourceMark rm;
1041    JavaThread *jt = (JavaThread *)THREAD;
1042    {
1043      // Atomic creation of array_klasses
1044      MutexLocker mc(Compile_lock, THREAD);   // for vtables
1045      MutexLocker ma(MultiArray_lock, THREAD);
1046
1047      // Check if update has already taken place
1048      if (this_k->array_klasses() == NULL) {
1049        Klass*    k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1050        this_k->set_array_klasses(k);
1051      }
1052    }
1053  }
1054  // _this will always be set at this point
1055  ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1056  if (or_null) {
1057    return oak->array_klass_or_null(n);
1058  }
1059  return oak->array_klass(n, THREAD);
1060}
1061
1062Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1063  return array_klass_impl(or_null, 1, THREAD);
1064}
1065
1066void InstanceKlass::call_class_initializer(TRAPS) {
1067  instanceKlassHandle ik (THREAD, this);
1068  call_class_initializer_impl(ik, THREAD);
1069}
1070
1071static int call_class_initializer_impl_counter = 0;   // for debugging
1072
1073Method* InstanceKlass::class_initializer() {
1074  Method* clinit = find_method(
1075      vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1076  if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1077    return clinit;
1078  }
1079  return NULL;
1080}
1081
1082void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1083  if (ReplayCompiles &&
1084      (ReplaySuppressInitializers == 1 ||
1085       ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1086    // Hide the existence of the initializer for the purpose of replaying the compile
1087    return;
1088  }
1089
1090  methodHandle h_method(THREAD, this_k->class_initializer());
1091  assert(!this_k->is_initialized(), "we cannot initialize twice");
1092  if (log_is_enabled(Info, classinit)) {
1093    ResourceMark rm;
1094    outputStream* log = LogHandle(classinit)::info_stream();
1095    log->print("%d Initializing ", call_class_initializer_impl_counter++);
1096    this_k->name()->print_value_on(log);
1097    log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k()));
1098  }
1099  if (h_method() != NULL) {
1100    JavaCallArguments args; // No arguments
1101    JavaValue result(T_VOID);
1102    JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1103  }
1104}
1105
1106
1107void InstanceKlass::mask_for(const methodHandle& method, int bci,
1108  InterpreterOopMap* entry_for) {
1109  // Dirty read, then double-check under a lock.
1110  if (_oop_map_cache == NULL) {
1111    // Otherwise, allocate a new one.
1112    MutexLocker x(OopMapCacheAlloc_lock);
1113    // First time use. Allocate a cache in C heap
1114    if (_oop_map_cache == NULL) {
1115      // Release stores from OopMapCache constructor before assignment
1116      // to _oop_map_cache. C++ compilers on ppc do not emit the
1117      // required memory barrier only because of the volatile
1118      // qualifier of _oop_map_cache.
1119      OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1120    }
1121  }
1122  // _oop_map_cache is constant after init; lookup below does is own locking.
1123  _oop_map_cache->lookup(method, bci, entry_for);
1124}
1125
1126
1127bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1128  for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1129    Symbol* f_name = fs.name();
1130    Symbol* f_sig  = fs.signature();
1131    if (f_name == name && f_sig == sig) {
1132      fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1133      return true;
1134    }
1135  }
1136  return false;
1137}
1138
1139
1140Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1141  const int n = local_interfaces()->length();
1142  for (int i = 0; i < n; i++) {
1143    Klass* intf1 = local_interfaces()->at(i);
1144    assert(intf1->is_interface(), "just checking type");
1145    // search for field in current interface
1146    if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1147      assert(fd->is_static(), "interface field must be static");
1148      return intf1;
1149    }
1150    // search for field in direct superinterfaces
1151    Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1152    if (intf2 != NULL) return intf2;
1153  }
1154  // otherwise field lookup fails
1155  return NULL;
1156}
1157
1158
1159Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1160  // search order according to newest JVM spec (5.4.3.2, p.167).
1161  // 1) search for field in current klass
1162  if (find_local_field(name, sig, fd)) {
1163    return const_cast<InstanceKlass*>(this);
1164  }
1165  // 2) search for field recursively in direct superinterfaces
1166  { Klass* intf = find_interface_field(name, sig, fd);
1167    if (intf != NULL) return intf;
1168  }
1169  // 3) apply field lookup recursively if superclass exists
1170  { Klass* supr = super();
1171    if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1172  }
1173  // 4) otherwise field lookup fails
1174  return NULL;
1175}
1176
1177
1178Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1179  // search order according to newest JVM spec (5.4.3.2, p.167).
1180  // 1) search for field in current klass
1181  if (find_local_field(name, sig, fd)) {
1182    if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1183  }
1184  // 2) search for field recursively in direct superinterfaces
1185  if (is_static) {
1186    Klass* intf = find_interface_field(name, sig, fd);
1187    if (intf != NULL) return intf;
1188  }
1189  // 3) apply field lookup recursively if superclass exists
1190  { Klass* supr = super();
1191    if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1192  }
1193  // 4) otherwise field lookup fails
1194  return NULL;
1195}
1196
1197
1198bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1199  for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1200    if (fs.offset() == offset) {
1201      fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1202      if (fd->is_static() == is_static) return true;
1203    }
1204  }
1205  return false;
1206}
1207
1208
1209bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1210  Klass* klass = const_cast<InstanceKlass*>(this);
1211  while (klass != NULL) {
1212    if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1213      return true;
1214    }
1215    klass = klass->super();
1216  }
1217  return false;
1218}
1219
1220
1221void InstanceKlass::methods_do(void f(Method* method)) {
1222  // Methods aren't stable until they are loaded.  This can be read outside
1223  // a lock through the ClassLoaderData for profiling
1224  if (!is_loaded()) {
1225    return;
1226  }
1227
1228  int len = methods()->length();
1229  for (int index = 0; index < len; index++) {
1230    Method* m = methods()->at(index);
1231    assert(m->is_method(), "must be method");
1232    f(m);
1233  }
1234}
1235
1236
1237void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1238  for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1239    if (fs.access_flags().is_static()) {
1240      fieldDescriptor& fd = fs.field_descriptor();
1241      cl->do_field(&fd);
1242    }
1243  }
1244}
1245
1246
1247void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1248  instanceKlassHandle h_this(THREAD, this);
1249  do_local_static_fields_impl(h_this, f, mirror, CHECK);
1250}
1251
1252
1253void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1254                             void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1255  for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1256    if (fs.access_flags().is_static()) {
1257      fieldDescriptor& fd = fs.field_descriptor();
1258      f(&fd, mirror, CHECK);
1259    }
1260  }
1261}
1262
1263
1264static int compare_fields_by_offset(int* a, int* b) {
1265  return a[0] - b[0];
1266}
1267
1268void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1269  InstanceKlass* super = superklass();
1270  if (super != NULL) {
1271    super->do_nonstatic_fields(cl);
1272  }
1273  fieldDescriptor fd;
1274  int length = java_fields_count();
1275  // In DebugInfo nonstatic fields are sorted by offset.
1276  int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1277  int j = 0;
1278  for (int i = 0; i < length; i += 1) {
1279    fd.reinitialize(this, i);
1280    if (!fd.is_static()) {
1281      fields_sorted[j + 0] = fd.offset();
1282      fields_sorted[j + 1] = i;
1283      j += 2;
1284    }
1285  }
1286  if (j > 0) {
1287    length = j;
1288    // _sort_Fn is defined in growableArray.hpp.
1289    qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1290    for (int i = 0; i < length; i += 2) {
1291      fd.reinitialize(this, fields_sorted[i + 1]);
1292      assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1293      cl->do_field(&fd);
1294    }
1295  }
1296  FREE_C_HEAP_ARRAY(int, fields_sorted);
1297}
1298
1299
1300void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1301  if (array_klasses() != NULL)
1302    ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1303}
1304
1305void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1306  if (array_klasses() != NULL)
1307    ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1308}
1309
1310#ifdef ASSERT
1311static int linear_search(const Array<Method*>* methods,
1312                         const Symbol* name,
1313                         const Symbol* signature) {
1314  const int len = methods->length();
1315  for (int index = 0; index < len; index++) {
1316    const Method* const m = methods->at(index);
1317    assert(m->is_method(), "must be method");
1318    if (m->signature() == signature && m->name() == name) {
1319       return index;
1320    }
1321  }
1322  return -1;
1323}
1324#endif
1325
1326static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1327  int len = methods->length();
1328  // methods are sorted, so do binary search
1329  int l = 0;
1330  int h = len - 1;
1331  while (l <= h) {
1332    int mid = (l + h) >> 1;
1333    Method* m = methods->at(mid);
1334    assert(m->is_method(), "must be method");
1335    int res = m->name()->fast_compare(name);
1336    if (res == 0) {
1337      return mid;
1338    } else if (res < 0) {
1339      l = mid + 1;
1340    } else {
1341      h = mid - 1;
1342    }
1343  }
1344  return -1;
1345}
1346
1347// find_method looks up the name/signature in the local methods array
1348Method* InstanceKlass::find_method(const Symbol* name,
1349                                   const Symbol* signature) const {
1350  return find_method_impl(name, signature, find_overpass, find_static, find_private);
1351}
1352
1353Method* InstanceKlass::find_method_impl(const Symbol* name,
1354                                        const Symbol* signature,
1355                                        OverpassLookupMode overpass_mode,
1356                                        StaticLookupMode static_mode,
1357                                        PrivateLookupMode private_mode) const {
1358  return InstanceKlass::find_method_impl(methods(),
1359                                         name,
1360                                         signature,
1361                                         overpass_mode,
1362                                         static_mode,
1363                                         private_mode);
1364}
1365
1366// find_instance_method looks up the name/signature in the local methods array
1367// and skips over static methods
1368Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1369                                            const Symbol* name,
1370                                            const Symbol* signature) {
1371  Method* const meth = InstanceKlass::find_method_impl(methods,
1372                                                 name,
1373                                                 signature,
1374                                                 find_overpass,
1375                                                 skip_static,
1376                                                 find_private);
1377  assert(((meth == NULL) || !meth->is_static()),
1378    "find_instance_method should have skipped statics");
1379  return meth;
1380}
1381
1382// find_instance_method looks up the name/signature in the local methods array
1383// and skips over static methods
1384Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1385  return InstanceKlass::find_instance_method(methods(), name, signature);
1386}
1387
1388// Find looks up the name/signature in the local methods array
1389// and filters on the overpass, static and private flags
1390// This returns the first one found
1391// note that the local methods array can have up to one overpass, one static
1392// and one instance (private or not) with the same name/signature
1393Method* InstanceKlass::find_local_method(const Symbol* name,
1394                                         const Symbol* signature,
1395                                         OverpassLookupMode overpass_mode,
1396                                         StaticLookupMode static_mode,
1397                                         PrivateLookupMode private_mode) const {
1398  return InstanceKlass::find_method_impl(methods(),
1399                                         name,
1400                                         signature,
1401                                         overpass_mode,
1402                                         static_mode,
1403                                         private_mode);
1404}
1405
1406// Find looks up the name/signature in the local methods array
1407// and filters on the overpass, static and private flags
1408// This returns the first one found
1409// note that the local methods array can have up to one overpass, one static
1410// and one instance (private or not) with the same name/signature
1411Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1412                                         const Symbol* name,
1413                                         const Symbol* signature,
1414                                         OverpassLookupMode overpass_mode,
1415                                         StaticLookupMode static_mode,
1416                                         PrivateLookupMode private_mode) {
1417  return InstanceKlass::find_method_impl(methods,
1418                                         name,
1419                                         signature,
1420                                         overpass_mode,
1421                                         static_mode,
1422                                         private_mode);
1423}
1424
1425Method* InstanceKlass::find_method(const Array<Method*>* methods,
1426                                   const Symbol* name,
1427                                   const Symbol* signature) {
1428  return InstanceKlass::find_method_impl(methods,
1429                                         name,
1430                                         signature,
1431                                         find_overpass,
1432                                         find_static,
1433                                         find_private);
1434}
1435
1436Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1437                                        const Symbol* name,
1438                                        const Symbol* signature,
1439                                        OverpassLookupMode overpass_mode,
1440                                        StaticLookupMode static_mode,
1441                                        PrivateLookupMode private_mode) {
1442  int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1443  return hit >= 0 ? methods->at(hit): NULL;
1444}
1445
1446// true if method matches signature and conforms to skipping_X conditions.
1447static bool method_matches(const Method* m,
1448                           const Symbol* signature,
1449                           bool skipping_overpass,
1450                           bool skipping_static,
1451                           bool skipping_private) {
1452  return ((m->signature() == signature) &&
1453    (!skipping_overpass || !m->is_overpass()) &&
1454    (!skipping_static || !m->is_static()) &&
1455    (!skipping_private || !m->is_private()));
1456}
1457
1458// Used directly for default_methods to find the index into the
1459// default_vtable_indices, and indirectly by find_method
1460// find_method_index looks in the local methods array to return the index
1461// of the matching name/signature. If, overpass methods are being ignored,
1462// the search continues to find a potential non-overpass match.  This capability
1463// is important during method resolution to prefer a static method, for example,
1464// over an overpass method.
1465// There is the possibility in any _method's array to have the same name/signature
1466// for a static method, an overpass method and a local instance method
1467// To correctly catch a given method, the search criteria may need
1468// to explicitly skip the other two. For local instance methods, it
1469// is often necessary to skip private methods
1470int InstanceKlass::find_method_index(const Array<Method*>* methods,
1471                                     const Symbol* name,
1472                                     const Symbol* signature,
1473                                     OverpassLookupMode overpass_mode,
1474                                     StaticLookupMode static_mode,
1475                                     PrivateLookupMode private_mode) {
1476  const bool skipping_overpass = (overpass_mode == skip_overpass);
1477  const bool skipping_static = (static_mode == skip_static);
1478  const bool skipping_private = (private_mode == skip_private);
1479  const int hit = binary_search(methods, name);
1480  if (hit != -1) {
1481    const Method* const m = methods->at(hit);
1482
1483    // Do linear search to find matching signature.  First, quick check
1484    // for common case, ignoring overpasses if requested.
1485    if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1486          return hit;
1487    }
1488
1489    // search downwards through overloaded methods
1490    int i;
1491    for (i = hit - 1; i >= 0; --i) {
1492        const Method* const m = methods->at(i);
1493        assert(m->is_method(), "must be method");
1494        if (m->name() != name) {
1495          break;
1496        }
1497        if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1498          return i;
1499        }
1500    }
1501    // search upwards
1502    for (i = hit + 1; i < methods->length(); ++i) {
1503        const Method* const m = methods->at(i);
1504        assert(m->is_method(), "must be method");
1505        if (m->name() != name) {
1506          break;
1507        }
1508        if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1509          return i;
1510        }
1511    }
1512    // not found
1513#ifdef ASSERT
1514    const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1515      linear_search(methods, name, signature);
1516    assert(-1 == index, "binary search should have found entry %d", index);
1517#endif
1518  }
1519  return -1;
1520}
1521
1522int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1523  return find_method_by_name(methods(), name, end);
1524}
1525
1526int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1527                                       const Symbol* name,
1528                                       int* end_ptr) {
1529  assert(end_ptr != NULL, "just checking");
1530  int start = binary_search(methods, name);
1531  int end = start + 1;
1532  if (start != -1) {
1533    while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1534    while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1535    *end_ptr = end;
1536    return start;
1537  }
1538  return -1;
1539}
1540
1541// uncached_lookup_method searches both the local class methods array and all
1542// superclasses methods arrays, skipping any overpass methods in superclasses.
1543Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1544                                              const Symbol* signature,
1545                                              OverpassLookupMode overpass_mode) const {
1546  OverpassLookupMode overpass_local_mode = overpass_mode;
1547  const Klass* klass = this;
1548  while (klass != NULL) {
1549    Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1550                                                                        signature,
1551                                                                        overpass_local_mode,
1552                                                                        find_static,
1553                                                                        find_private);
1554    if (method != NULL) {
1555      return method;
1556    }
1557    klass = klass->super();
1558    overpass_local_mode = skip_overpass;   // Always ignore overpass methods in superclasses
1559  }
1560  return NULL;
1561}
1562
1563#ifdef ASSERT
1564// search through class hierarchy and return true if this class or
1565// one of the superclasses was redefined
1566bool InstanceKlass::has_redefined_this_or_super() const {
1567  const Klass* klass = this;
1568  while (klass != NULL) {
1569    if (InstanceKlass::cast(klass)->has_been_redefined()) {
1570      return true;
1571    }
1572    klass = klass->super();
1573  }
1574  return false;
1575}
1576#endif
1577
1578// lookup a method in the default methods list then in all transitive interfaces
1579// Do NOT return private or static methods
1580Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1581                                                         Symbol* signature) const {
1582  Method* m = NULL;
1583  if (default_methods() != NULL) {
1584    m = find_method(default_methods(), name, signature);
1585  }
1586  // Look up interfaces
1587  if (m == NULL) {
1588    m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1589  }
1590  return m;
1591}
1592
1593// lookup a method in all the interfaces that this class implements
1594// Do NOT return private or static methods, new in JDK8 which are not externally visible
1595// They should only be found in the initial InterfaceMethodRef
1596Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1597                                                       Symbol* signature,
1598                                                       DefaultsLookupMode defaults_mode) const {
1599  Array<Klass*>* all_ifs = transitive_interfaces();
1600  int num_ifs = all_ifs->length();
1601  InstanceKlass *ik = NULL;
1602  for (int i = 0; i < num_ifs; i++) {
1603    ik = InstanceKlass::cast(all_ifs->at(i));
1604    Method* m = ik->lookup_method(name, signature);
1605    if (m != NULL && m->is_public() && !m->is_static() &&
1606        ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1607      return m;
1608    }
1609  }
1610  return NULL;
1611}
1612
1613/* jni_id_for_impl for jfieldIds only */
1614JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1615  MutexLocker ml(JfieldIdCreation_lock);
1616  // Retry lookup after we got the lock
1617  JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1618  if (probe == NULL) {
1619    // Slow case, allocate new static field identifier
1620    probe = new JNIid(this_k(), offset, this_k->jni_ids());
1621    this_k->set_jni_ids(probe);
1622  }
1623  return probe;
1624}
1625
1626
1627/* jni_id_for for jfieldIds only */
1628JNIid* InstanceKlass::jni_id_for(int offset) {
1629  JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1630  if (probe == NULL) {
1631    probe = jni_id_for_impl(this, offset);
1632  }
1633  return probe;
1634}
1635
1636u2 InstanceKlass::enclosing_method_data(int offset) const {
1637  const Array<jushort>* const inner_class_list = inner_classes();
1638  if (inner_class_list == NULL) {
1639    return 0;
1640  }
1641  const int length = inner_class_list->length();
1642  if (length % inner_class_next_offset == 0) {
1643    return 0;
1644  }
1645  const int index = length - enclosing_method_attribute_size;
1646  assert(offset < enclosing_method_attribute_size, "invalid offset");
1647  return inner_class_list->at(index + offset);
1648}
1649
1650void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1651                                                 u2 method_index) {
1652  Array<jushort>* inner_class_list = inner_classes();
1653  assert (inner_class_list != NULL, "_inner_classes list is not set up");
1654  int length = inner_class_list->length();
1655  if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1656    int index = length - enclosing_method_attribute_size;
1657    inner_class_list->at_put(
1658      index + enclosing_method_class_index_offset, class_index);
1659    inner_class_list->at_put(
1660      index + enclosing_method_method_index_offset, method_index);
1661  }
1662}
1663
1664// Lookup or create a jmethodID.
1665// This code is called by the VMThread and JavaThreads so the
1666// locking has to be done very carefully to avoid deadlocks
1667// and/or other cache consistency problems.
1668//
1669jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, const methodHandle& method_h) {
1670  size_t idnum = (size_t)method_h->method_idnum();
1671  jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1672  size_t length = 0;
1673  jmethodID id = NULL;
1674
1675  // We use a double-check locking idiom here because this cache is
1676  // performance sensitive. In the normal system, this cache only
1677  // transitions from NULL to non-NULL which is safe because we use
1678  // release_set_methods_jmethod_ids() to advertise the new cache.
1679  // A partially constructed cache should never be seen by a racing
1680  // thread. We also use release_store_ptr() to save a new jmethodID
1681  // in the cache so a partially constructed jmethodID should never be
1682  // seen either. Cache reads of existing jmethodIDs proceed without a
1683  // lock, but cache writes of a new jmethodID requires uniqueness and
1684  // creation of the cache itself requires no leaks so a lock is
1685  // generally acquired in those two cases.
1686  //
1687  // If the RedefineClasses() API has been used, then this cache can
1688  // grow and we'll have transitions from non-NULL to bigger non-NULL.
1689  // Cache creation requires no leaks and we require safety between all
1690  // cache accesses and freeing of the old cache so a lock is generally
1691  // acquired when the RedefineClasses() API has been used.
1692
1693  if (jmeths != NULL) {
1694    // the cache already exists
1695    if (!ik_h->idnum_can_increment()) {
1696      // the cache can't grow so we can just get the current values
1697      get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1698    } else {
1699      // cache can grow so we have to be more careful
1700      if (Threads::number_of_threads() == 0 ||
1701          SafepointSynchronize::is_at_safepoint()) {
1702        // we're single threaded or at a safepoint - no locking needed
1703        get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1704      } else {
1705        MutexLocker ml(JmethodIdCreation_lock);
1706        get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1707      }
1708    }
1709  }
1710  // implied else:
1711  // we need to allocate a cache so default length and id values are good
1712
1713  if (jmeths == NULL ||   // no cache yet
1714      length <= idnum ||  // cache is too short
1715      id == NULL) {       // cache doesn't contain entry
1716
1717    // This function can be called by the VMThread so we have to do all
1718    // things that might block on a safepoint before grabbing the lock.
1719    // Otherwise, we can deadlock with the VMThread or have a cache
1720    // consistency issue. These vars keep track of what we might have
1721    // to free after the lock is dropped.
1722    jmethodID  to_dealloc_id     = NULL;
1723    jmethodID* to_dealloc_jmeths = NULL;
1724
1725    // may not allocate new_jmeths or use it if we allocate it
1726    jmethodID* new_jmeths = NULL;
1727    if (length <= idnum) {
1728      // allocate a new cache that might be used
1729      size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1730      new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1731      memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1732      // cache size is stored in element[0], other elements offset by one
1733      new_jmeths[0] = (jmethodID)size;
1734    }
1735
1736    // allocate a new jmethodID that might be used
1737    jmethodID new_id = NULL;
1738    if (method_h->is_old() && !method_h->is_obsolete()) {
1739      // The method passed in is old (but not obsolete), we need to use the current version
1740      Method* current_method = ik_h->method_with_idnum((int)idnum);
1741      assert(current_method != NULL, "old and but not obsolete, so should exist");
1742      new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1743    } else {
1744      // It is the current version of the method or an obsolete method,
1745      // use the version passed in
1746      new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1747    }
1748
1749    if (Threads::number_of_threads() == 0 ||
1750        SafepointSynchronize::is_at_safepoint()) {
1751      // we're single threaded or at a safepoint - no locking needed
1752      id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1753                                          &to_dealloc_id, &to_dealloc_jmeths);
1754    } else {
1755      MutexLocker ml(JmethodIdCreation_lock);
1756      id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1757                                          &to_dealloc_id, &to_dealloc_jmeths);
1758    }
1759
1760    // The lock has been dropped so we can free resources.
1761    // Free up either the old cache or the new cache if we allocated one.
1762    if (to_dealloc_jmeths != NULL) {
1763      FreeHeap(to_dealloc_jmeths);
1764    }
1765    // free up the new ID since it wasn't needed
1766    if (to_dealloc_id != NULL) {
1767      Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1768    }
1769  }
1770  return id;
1771}
1772
1773// Figure out how many jmethodIDs haven't been allocated, and make
1774// sure space for them is pre-allocated.  This makes getting all
1775// method ids much, much faster with classes with more than 8
1776// methods, and has a *substantial* effect on performance with jvmti
1777// code that loads all jmethodIDs for all classes.
1778void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1779  int new_jmeths = 0;
1780  int length = methods()->length();
1781  for (int index = start_offset; index < length; index++) {
1782    Method* m = methods()->at(index);
1783    jmethodID id = m->find_jmethod_id_or_null();
1784    if (id == NULL) {
1785      new_jmeths++;
1786    }
1787  }
1788  if (new_jmeths != 0) {
1789    Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1790  }
1791}
1792
1793// Common code to fetch the jmethodID from the cache or update the
1794// cache with the new jmethodID. This function should never do anything
1795// that causes the caller to go to a safepoint or we can deadlock with
1796// the VMThread or have cache consistency issues.
1797//
1798jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1799            instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1800            jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1801            jmethodID** to_dealloc_jmeths_p) {
1802  assert(new_id != NULL, "sanity check");
1803  assert(to_dealloc_id_p != NULL, "sanity check");
1804  assert(to_dealloc_jmeths_p != NULL, "sanity check");
1805  assert(Threads::number_of_threads() == 0 ||
1806         SafepointSynchronize::is_at_safepoint() ||
1807         JmethodIdCreation_lock->owned_by_self(), "sanity check");
1808
1809  // reacquire the cache - we are locked, single threaded or at a safepoint
1810  jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1811  jmethodID  id     = NULL;
1812  size_t     length = 0;
1813
1814  if (jmeths == NULL ||                         // no cache yet
1815      (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
1816    if (jmeths != NULL) {
1817      // copy any existing entries from the old cache
1818      for (size_t index = 0; index < length; index++) {
1819        new_jmeths[index+1] = jmeths[index+1];
1820      }
1821      *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
1822    }
1823    ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1824  } else {
1825    // fetch jmethodID (if any) from the existing cache
1826    id = jmeths[idnum+1];
1827    *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
1828  }
1829  if (id == NULL) {
1830    // No matching jmethodID in the existing cache or we have a new
1831    // cache or we just grew the cache. This cache write is done here
1832    // by the first thread to win the foot race because a jmethodID
1833    // needs to be unique once it is generally available.
1834    id = new_id;
1835
1836    // The jmethodID cache can be read while unlocked so we have to
1837    // make sure the new jmethodID is complete before installing it
1838    // in the cache.
1839    OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1840  } else {
1841    *to_dealloc_id_p = new_id; // save new id for later delete
1842  }
1843  return id;
1844}
1845
1846
1847// Common code to get the jmethodID cache length and the jmethodID
1848// value at index idnum if there is one.
1849//
1850void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1851       size_t idnum, size_t *length_p, jmethodID* id_p) {
1852  assert(cache != NULL, "sanity check");
1853  assert(length_p != NULL, "sanity check");
1854  assert(id_p != NULL, "sanity check");
1855
1856  // cache size is stored in element[0], other elements offset by one
1857  *length_p = (size_t)cache[0];
1858  if (*length_p <= idnum) {  // cache is too short
1859    *id_p = NULL;
1860  } else {
1861    *id_p = cache[idnum+1];  // fetch jmethodID (if any)
1862  }
1863}
1864
1865
1866// Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
1867jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1868  size_t idnum = (size_t)method->method_idnum();
1869  jmethodID* jmeths = methods_jmethod_ids_acquire();
1870  size_t length;                                // length assigned as debugging crumb
1871  jmethodID id = NULL;
1872  if (jmeths != NULL &&                         // If there is a cache
1873      (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
1874    id = jmeths[idnum+1];                       // Look up the id (may be NULL)
1875  }
1876  return id;
1877}
1878
1879inline DependencyContext InstanceKlass::dependencies() {
1880  DependencyContext dep_context(&_dep_context);
1881  return dep_context;
1882}
1883
1884int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1885  return dependencies().mark_dependent_nmethods(changes);
1886}
1887
1888void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1889  dependencies().add_dependent_nmethod(nm);
1890}
1891
1892void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1893  dependencies().remove_dependent_nmethod(nm, delete_immediately);
1894}
1895
1896#ifndef PRODUCT
1897void InstanceKlass::print_dependent_nmethods(bool verbose) {
1898  dependencies().print_dependent_nmethods(verbose);
1899}
1900
1901bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1902  return dependencies().is_dependent_nmethod(nm);
1903}
1904#endif //PRODUCT
1905
1906void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
1907  clean_implementors_list(is_alive);
1908  clean_method_data(is_alive);
1909
1910  // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
1911  DependencyContext dep_context(&_dep_context);
1912  dep_context.expunge_stale_entries();
1913}
1914
1915void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
1916  assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
1917  if (is_interface()) {
1918    if (ClassUnloading) {
1919      Klass* impl = implementor();
1920      if (impl != NULL) {
1921        if (!impl->is_loader_alive(is_alive)) {
1922          // remove this guy
1923          Klass** klass = adr_implementor();
1924          assert(klass != NULL, "null klass");
1925          if (klass != NULL) {
1926            *klass = NULL;
1927          }
1928        }
1929      }
1930    }
1931  }
1932}
1933
1934void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
1935  for (int m = 0; m < methods()->length(); m++) {
1936    MethodData* mdo = methods()->at(m)->method_data();
1937    if (mdo != NULL) {
1938      mdo->clean_method_data(is_alive);
1939    }
1940  }
1941}
1942
1943
1944static void remove_unshareable_in_class(Klass* k) {
1945  // remove klass's unshareable info
1946  k->remove_unshareable_info();
1947}
1948
1949void InstanceKlass::remove_unshareable_info() {
1950  Klass::remove_unshareable_info();
1951  // Unlink the class
1952  if (is_linked()) {
1953    unlink_class();
1954  }
1955  init_implementor();
1956
1957  constants()->remove_unshareable_info();
1958
1959  assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable");
1960
1961  for (int i = 0; i < methods()->length(); i++) {
1962    Method* m = methods()->at(i);
1963    m->remove_unshareable_info();
1964  }
1965
1966  // do array classes also.
1967  array_klasses_do(remove_unshareable_in_class);
1968}
1969
1970static void restore_unshareable_in_class(Klass* k, TRAPS) {
1971  // Array classes have null protection domain.
1972  // --> see ArrayKlass::complete_create_array_klass()
1973  k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
1974}
1975
1976void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
1977  Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
1978  instanceKlassHandle ik(THREAD, this);
1979
1980  Array<Method*>* methods = ik->methods();
1981  int num_methods = methods->length();
1982  for (int index2 = 0; index2 < num_methods; ++index2) {
1983    methodHandle m(THREAD, methods->at(index2));
1984    m->restore_unshareable_info(CHECK);
1985  }
1986  if (JvmtiExport::has_redefined_a_class()) {
1987    // Reinitialize vtable because RedefineClasses may have changed some
1988    // entries in this vtable for super classes so the CDS vtable might
1989    // point to old or obsolete entries.  RedefineClasses doesn't fix up
1990    // vtables in the shared system dictionary, only the main one.
1991    // It also redefines the itable too so fix that too.
1992    ResourceMark rm(THREAD);
1993    ik->vtable()->initialize_vtable(false, CHECK);
1994    ik->itable()->initialize_itable(false, CHECK);
1995  }
1996
1997  // restore constant pool resolved references
1998  ik->constants()->restore_unshareable_info(CHECK);
1999
2000  ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2001}
2002
2003// returns true IFF is_in_error_state() has been changed as a result of this call.
2004bool InstanceKlass::check_sharing_error_state() {
2005  assert(DumpSharedSpaces, "should only be called during dumping");
2006  bool old_state = is_in_error_state();
2007
2008  if (!is_in_error_state()) {
2009    bool bad = false;
2010    for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2011      if (sup->is_in_error_state()) {
2012        bad = true;
2013        break;
2014      }
2015    }
2016    if (!bad) {
2017      Array<Klass*>* interfaces = transitive_interfaces();
2018      for (int i = 0; i < interfaces->length(); i++) {
2019        Klass* iface = interfaces->at(i);
2020        if (InstanceKlass::cast(iface)->is_in_error_state()) {
2021          bad = true;
2022          break;
2023        }
2024      }
2025    }
2026
2027    if (bad) {
2028      set_in_error_state();
2029    }
2030  }
2031
2032  return (old_state != is_in_error_state());
2033}
2034
2035static void clear_all_breakpoints(Method* m) {
2036  m->clear_all_breakpoints();
2037}
2038
2039
2040void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2041  // notify the debugger
2042  if (JvmtiExport::should_post_class_unload()) {
2043    JvmtiExport::post_class_unload(ik);
2044  }
2045
2046  // notify ClassLoadingService of class unload
2047  ClassLoadingService::notify_class_unloaded(ik);
2048}
2049
2050void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2051  // Clean up C heap
2052  ik->release_C_heap_structures();
2053  ik->constants()->release_C_heap_structures();
2054}
2055
2056void InstanceKlass::release_C_heap_structures() {
2057
2058  // Can't release the constant pool here because the constant pool can be
2059  // deallocated separately from the InstanceKlass for default methods and
2060  // redefine classes.
2061
2062  // Deallocate oop map cache
2063  if (_oop_map_cache != NULL) {
2064    delete _oop_map_cache;
2065    _oop_map_cache = NULL;
2066  }
2067
2068  // Deallocate JNI identifiers for jfieldIDs
2069  JNIid::deallocate(jni_ids());
2070  set_jni_ids(NULL);
2071
2072  jmethodID* jmeths = methods_jmethod_ids_acquire();
2073  if (jmeths != (jmethodID*)NULL) {
2074    release_set_methods_jmethod_ids(NULL);
2075    FreeHeap(jmeths);
2076  }
2077
2078  // Deallocate MemberNameTable
2079  {
2080    Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2081    MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2082    MemberNameTable* mnt = member_names();
2083    if (mnt != NULL) {
2084      delete mnt;
2085      set_member_names(NULL);
2086    }
2087  }
2088
2089  // Release dependencies.
2090  // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2091  // it is not safe (see JDK-8143408). The problem is that the klass dependency
2092  // context can contain live dependencies, since there's a race between nmethod &
2093  // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2094  // dependencies aren't removed from the context associated with the class (see
2095  // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2096  // live dependencies pointing to unloaded nmethods and causes a crash in
2097  // DC::remove_all_dependents() when it touches unloaded nmethod.
2098  dependencies().wipe();
2099
2100  // Deallocate breakpoint records
2101  if (breakpoints() != 0x0) {
2102    methods_do(clear_all_breakpoints);
2103    assert(breakpoints() == 0x0, "should have cleared breakpoints");
2104  }
2105
2106  // deallocate the cached class file
2107  if (_cached_class_file != NULL) {
2108    os::free(_cached_class_file);
2109    _cached_class_file = NULL;
2110  }
2111
2112  // Decrement symbol reference counts associated with the unloaded class.
2113  if (_name != NULL) _name->decrement_refcount();
2114  // unreference array name derived from this class name (arrays of an unloaded
2115  // class can't be referenced anymore).
2116  if (_array_name != NULL)  _array_name->decrement_refcount();
2117  if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2118
2119  assert(_total_instanceKlass_count >= 1, "Sanity check");
2120  Atomic::dec(&_total_instanceKlass_count);
2121}
2122
2123void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2124  if (array == NULL) {
2125    _source_debug_extension = NULL;
2126  } else {
2127    // Adding one to the attribute length in order to store a null terminator
2128    // character could cause an overflow because the attribute length is
2129    // already coded with an u4 in the classfile, but in practice, it's
2130    // unlikely to happen.
2131    assert((length+1) > length, "Overflow checking");
2132    char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2133    for (int i = 0; i < length; i++) {
2134      sde[i] = array[i];
2135    }
2136    sde[length] = '\0';
2137    _source_debug_extension = sde;
2138  }
2139}
2140
2141address InstanceKlass::static_field_addr(int offset) {
2142  return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2143}
2144
2145
2146const char* InstanceKlass::signature_name() const {
2147  int hash_len = 0;
2148  char hash_buf[40];
2149
2150  // If this is an anonymous class, append a hash to make the name unique
2151  if (is_anonymous()) {
2152    intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2153    jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2154    hash_len = (int)strlen(hash_buf);
2155  }
2156
2157  // Get the internal name as a c string
2158  const char* src = (const char*) (name()->as_C_string());
2159  const int src_length = (int)strlen(src);
2160
2161  char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2162
2163  // Add L as type indicator
2164  int dest_index = 0;
2165  dest[dest_index++] = 'L';
2166
2167  // Add the actual class name
2168  for (int src_index = 0; src_index < src_length; ) {
2169    dest[dest_index++] = src[src_index++];
2170  }
2171
2172  // If we have a hash, append it
2173  for (int hash_index = 0; hash_index < hash_len; ) {
2174    dest[dest_index++] = hash_buf[hash_index++];
2175  }
2176
2177  // Add the semicolon and the NULL
2178  dest[dest_index++] = ';';
2179  dest[dest_index] = '\0';
2180  return dest;
2181}
2182
2183// different verisons of is_same_class_package
2184bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2185  const Klass* const class1 = (const Klass* const)this;
2186  oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2187  const Symbol* const classname1 = class1->name();
2188
2189  if (class2->is_objArray_klass()) {
2190    class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2191  }
2192  oop classloader2;
2193  if (class2->is_instance_klass()) {
2194    classloader2 = InstanceKlass::cast(class2)->class_loader();
2195  } else {
2196    assert(class2->is_typeArray_klass(), "should be type array");
2197    classloader2 = NULL;
2198  }
2199  const Symbol* classname2 = class2->name();
2200
2201  return InstanceKlass::is_same_class_package(classloader1, classname1,
2202                                              classloader2, classname2);
2203}
2204
2205bool InstanceKlass::is_same_class_package(oop other_class_loader,
2206                                          const Symbol* other_class_name) const {
2207  oop this_class_loader = class_loader();
2208  const Symbol* const this_class_name = name();
2209
2210  return InstanceKlass::is_same_class_package(this_class_loader,
2211                                             this_class_name,
2212                                             other_class_loader,
2213                                             other_class_name);
2214}
2215
2216// return true if two classes are in the same package, classloader
2217// and classname information is enough to determine a class's package
2218bool InstanceKlass::is_same_class_package(oop class_loader1, const Symbol* class_name1,
2219                                          oop class_loader2, const Symbol* class_name2) {
2220  if (class_loader1 != class_loader2) {
2221    return false;
2222  } else if (class_name1 == class_name2) {
2223    return true;                // skip painful bytewise comparison
2224  } else {
2225    ResourceMark rm;
2226
2227    // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2228    // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2229    // Otherwise, we just compare jbyte values between the strings.
2230    const jbyte *name1 = class_name1->base();
2231    const jbyte *name2 = class_name2->base();
2232
2233    const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2234    const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2235
2236    if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2237      // One of the two doesn't have a package.  Only return true
2238      // if the other one also doesn't have a package.
2239      return last_slash1 == last_slash2;
2240    } else {
2241      // Skip over '['s
2242      if (*name1 == '[') {
2243        do {
2244          name1++;
2245        } while (*name1 == '[');
2246        if (*name1 != 'L') {
2247          // Something is terribly wrong.  Shouldn't be here.
2248          return false;
2249        }
2250      }
2251      if (*name2 == '[') {
2252        do {
2253          name2++;
2254        } while (*name2 == '[');
2255        if (*name2 != 'L') {
2256          // Something is terribly wrong.  Shouldn't be here.
2257          return false;
2258        }
2259      }
2260
2261      // Check that package part is identical
2262      int length1 = last_slash1 - name1;
2263      int length2 = last_slash2 - name2;
2264
2265      return UTF8::equal(name1, length1, name2, length2);
2266    }
2267  }
2268}
2269
2270// Returns true iff super_method can be overridden by a method in targetclassname
2271// See JSL 3rd edition 8.4.6.1
2272// Assumes name-signature match
2273// "this" is InstanceKlass of super_method which must exist
2274// note that the InstanceKlass of the method in the targetclassname has not always been created yet
2275bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2276   // Private methods can not be overridden
2277   if (super_method->is_private()) {
2278     return false;
2279   }
2280   // If super method is accessible, then override
2281   if ((super_method->is_protected()) ||
2282       (super_method->is_public())) {
2283     return true;
2284   }
2285   // Package-private methods are not inherited outside of package
2286   assert(super_method->is_package_private(), "must be package private");
2287   return(is_same_class_package(targetclassloader(), targetclassname));
2288}
2289
2290/* defined for now in jvm.cpp, for historical reasons *--
2291Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2292                                                     Symbol*& simple_name_result, TRAPS) {
2293  ...
2294}
2295*/
2296
2297// tell if two classes have the same enclosing class (at package level)
2298bool InstanceKlass::is_same_package_member_impl(const InstanceKlass* class1,
2299                                                const Klass* class2,
2300                                                TRAPS) {
2301  if (class2 == class1) return true;
2302  if (!class2->is_instance_klass())  return false;
2303
2304  // must be in same package before we try anything else
2305  if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2306    return false;
2307
2308  // As long as there is an outer1.getEnclosingClass,
2309  // shift the search outward.
2310  const InstanceKlass* outer1 = class1;
2311  for (;;) {
2312    // As we walk along, look for equalities between outer1 and class2.
2313    // Eventually, the walks will terminate as outer1 stops
2314    // at the top-level class around the original class.
2315    bool ignore_inner_is_member;
2316    const Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2317                                                  CHECK_false);
2318    if (next == NULL)  break;
2319    if (next == class2)  return true;
2320    outer1 = InstanceKlass::cast(next);
2321  }
2322
2323  // Now do the same for class2.
2324  const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2325  for (;;) {
2326    bool ignore_inner_is_member;
2327    Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2328                                                    CHECK_false);
2329    if (next == NULL)  break;
2330    // Might as well check the new outer against all available values.
2331    if (next == class1)  return true;
2332    if (next == outer1)  return true;
2333    outer2 = InstanceKlass::cast(next);
2334  }
2335
2336  // If by this point we have not found an equality between the
2337  // two classes, we know they are in separate package members.
2338  return false;
2339}
2340
2341bool InstanceKlass::find_inner_classes_attr(instanceKlassHandle k, int* ooff, int* noff, TRAPS) {
2342  constantPoolHandle i_cp(THREAD, k->constants());
2343  for (InnerClassesIterator iter(k); !iter.done(); iter.next()) {
2344    int ioff = iter.inner_class_info_index();
2345    if (ioff != 0) {
2346      // Check to see if the name matches the class we're looking for
2347      // before attempting to find the class.
2348      if (i_cp->klass_name_at_matches(k, ioff)) {
2349        Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2350        if (k() == inner_klass) {
2351          *ooff = iter.outer_class_info_index();
2352          *noff = iter.inner_name_index();
2353          return true;
2354        }
2355      }
2356    }
2357  }
2358  return false;
2359}
2360
2361InstanceKlass* InstanceKlass::compute_enclosing_class_impl(const InstanceKlass* k,
2362                                                           bool* inner_is_member,
2363                                                           TRAPS) {
2364  InstanceKlass* outer_klass = NULL;
2365  *inner_is_member = false;
2366  int ooff = 0, noff = 0;
2367  if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) {
2368    constantPoolHandle i_cp(THREAD, k->constants());
2369    if (ooff != 0) {
2370      Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2371      outer_klass = InstanceKlass::cast(ok);
2372      *inner_is_member = true;
2373    }
2374    if (NULL == outer_klass) {
2375      // It may be anonymous; try for that.
2376      int encl_method_class_idx = k->enclosing_method_class_index();
2377      if (encl_method_class_idx != 0) {
2378        Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2379        outer_klass = InstanceKlass::cast(ok);
2380        *inner_is_member = false;
2381      }
2382    }
2383  }
2384
2385  // If no inner class attribute found for this class.
2386  if (NULL == outer_klass) return NULL;
2387
2388  // Throws an exception if outer klass has not declared k as an inner klass
2389  // We need evidence that each klass knows about the other, or else
2390  // the system could allow a spoof of an inner class to gain access rights.
2391  Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL);
2392  return outer_klass;
2393}
2394
2395jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2396  jint access = access_flags().as_int();
2397
2398  // But check if it happens to be member class.
2399  instanceKlassHandle ik(THREAD, this);
2400  InnerClassesIterator iter(ik);
2401  for (; !iter.done(); iter.next()) {
2402    int ioff = iter.inner_class_info_index();
2403    // Inner class attribute can be zero, skip it.
2404    // Strange but true:  JVM spec. allows null inner class refs.
2405    if (ioff == 0) continue;
2406
2407    // only look at classes that are already loaded
2408    // since we are looking for the flags for our self.
2409    Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2410    if ((ik->name() == inner_name)) {
2411      // This is really a member class.
2412      access = iter.inner_access_flags();
2413      break;
2414    }
2415  }
2416  // Remember to strip ACC_SUPER bit
2417  return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2418}
2419
2420jint InstanceKlass::jvmti_class_status() const {
2421  jint result = 0;
2422
2423  if (is_linked()) {
2424    result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2425  }
2426
2427  if (is_initialized()) {
2428    assert(is_linked(), "Class status is not consistent");
2429    result |= JVMTI_CLASS_STATUS_INITIALIZED;
2430  }
2431  if (is_in_error_state()) {
2432    result |= JVMTI_CLASS_STATUS_ERROR;
2433  }
2434  return result;
2435}
2436
2437Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2438  itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2439  int method_table_offset_in_words = ioe->offset()/wordSize;
2440  int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2441                       / itableOffsetEntry::size();
2442
2443  for (int cnt = 0 ; ; cnt ++, ioe ++) {
2444    // If the interface isn't implemented by the receiver class,
2445    // the VM should throw IncompatibleClassChangeError.
2446    if (cnt >= nof_interfaces) {
2447      THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2448    }
2449
2450    Klass* ik = ioe->interface_klass();
2451    if (ik == holder) break;
2452  }
2453
2454  itableMethodEntry* ime = ioe->first_method_entry(this);
2455  Method* m = ime[index].method();
2456  if (m == NULL) {
2457    THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2458  }
2459  return m;
2460}
2461
2462
2463#if INCLUDE_JVMTI
2464// update default_methods for redefineclasses for methods that are
2465// not yet in the vtable due to concurrent subclass define and superinterface
2466// redefinition
2467// Note: those in the vtable, should have been updated via adjust_method_entries
2468void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2469  // search the default_methods for uses of either obsolete or EMCP methods
2470  if (default_methods() != NULL) {
2471    for (int index = 0; index < default_methods()->length(); index ++) {
2472      Method* old_method = default_methods()->at(index);
2473      if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2474        continue; // skip uninteresting entries
2475      }
2476      assert(!old_method->is_deleted(), "default methods may not be deleted");
2477
2478      Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2479
2480      assert(new_method != NULL, "method_with_idnum() should not be NULL");
2481      assert(old_method != new_method, "sanity check");
2482
2483      default_methods()->at_put(index, new_method);
2484      if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2485        if (!(*trace_name_printed)) {
2486          // RC_TRACE_MESG macro has an embedded ResourceMark
2487          RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2488                         external_name(),
2489                         old_method->method_holder()->external_name()));
2490          *trace_name_printed = true;
2491        }
2492        RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2493                              new_method->name()->as_C_string(),
2494                              new_method->signature()->as_C_string()));
2495      }
2496    }
2497  }
2498}
2499#endif // INCLUDE_JVMTI
2500
2501// On-stack replacement stuff
2502void InstanceKlass::add_osr_nmethod(nmethod* n) {
2503  // only one compilation can be active
2504  {
2505    // This is a short non-blocking critical region, so the no safepoint check is ok.
2506    MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2507    assert(n->is_osr_method(), "wrong kind of nmethod");
2508    n->set_osr_link(osr_nmethods_head());
2509    set_osr_nmethods_head(n);
2510    // Raise the highest osr level if necessary
2511    if (TieredCompilation) {
2512      Method* m = n->method();
2513      m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2514    }
2515  }
2516
2517  // Get rid of the osr methods for the same bci that have lower levels.
2518  if (TieredCompilation) {
2519    for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2520      nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2521      if (inv != NULL && inv->is_in_use()) {
2522        inv->make_not_entrant();
2523      }
2524    }
2525  }
2526}
2527
2528
2529void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2530  // This is a short non-blocking critical region, so the no safepoint check is ok.
2531  MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2532  assert(n->is_osr_method(), "wrong kind of nmethod");
2533  nmethod* last = NULL;
2534  nmethod* cur  = osr_nmethods_head();
2535  int max_level = CompLevel_none;  // Find the max comp level excluding n
2536  Method* m = n->method();
2537  // Search for match
2538  while(cur != NULL && cur != n) {
2539    if (TieredCompilation && m == cur->method()) {
2540      // Find max level before n
2541      max_level = MAX2(max_level, cur->comp_level());
2542    }
2543    last = cur;
2544    cur = cur->osr_link();
2545  }
2546  nmethod* next = NULL;
2547  if (cur == n) {
2548    next = cur->osr_link();
2549    if (last == NULL) {
2550      // Remove first element
2551      set_osr_nmethods_head(next);
2552    } else {
2553      last->set_osr_link(next);
2554    }
2555  }
2556  n->set_osr_link(NULL);
2557  if (TieredCompilation) {
2558    cur = next;
2559    while (cur != NULL) {
2560      // Find max level after n
2561      if (m == cur->method()) {
2562        max_level = MAX2(max_level, cur->comp_level());
2563      }
2564      cur = cur->osr_link();
2565    }
2566    m->set_highest_osr_comp_level(max_level);
2567  }
2568}
2569
2570int InstanceKlass::mark_osr_nmethods(const Method* m) {
2571  // This is a short non-blocking critical region, so the no safepoint check is ok.
2572  MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2573  nmethod* osr = osr_nmethods_head();
2574  int found = 0;
2575  while (osr != NULL) {
2576    assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2577    if (osr->method() == m) {
2578      osr->mark_for_deoptimization();
2579      found++;
2580    }
2581    osr = osr->osr_link();
2582  }
2583  return found;
2584}
2585
2586nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2587  // This is a short non-blocking critical region, so the no safepoint check is ok.
2588  MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2589  nmethod* osr = osr_nmethods_head();
2590  nmethod* best = NULL;
2591  while (osr != NULL) {
2592    assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2593    // There can be a time when a c1 osr method exists but we are waiting
2594    // for a c2 version. When c2 completes its osr nmethod we will trash
2595    // the c1 version and only be able to find the c2 version. However
2596    // while we overflow in the c1 code at back branches we don't want to
2597    // try and switch to the same code as we are already running
2598
2599    if (osr->method() == m &&
2600        (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2601      if (match_level) {
2602        if (osr->comp_level() == comp_level) {
2603          // Found a match - return it.
2604          return osr;
2605        }
2606      } else {
2607        if (best == NULL || (osr->comp_level() > best->comp_level())) {
2608          if (osr->comp_level() == CompLevel_highest_tier) {
2609            // Found the best possible - return it.
2610            return osr;
2611          }
2612          best = osr;
2613        }
2614      }
2615    }
2616    osr = osr->osr_link();
2617  }
2618  if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2619    return best;
2620  }
2621  return NULL;
2622}
2623
2624bool InstanceKlass::add_member_name(Handle mem_name) {
2625  jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2626  MutexLocker ml(MemberNameTable_lock);
2627  DEBUG_ONLY(No_Safepoint_Verifier nsv);
2628
2629  // Check if method has been redefined while taking out MemberNameTable_lock, if so
2630  // return false.  We cannot cache obsolete methods. They will crash when the function
2631  // is called!
2632  Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
2633  if (method->is_obsolete()) {
2634    return false;
2635  } else if (method->is_old()) {
2636    // Replace method with redefined version
2637    java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
2638  }
2639
2640  if (_member_names == NULL) {
2641    _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2642  }
2643  _member_names->add_member_name(mem_name_wref);
2644  return true;
2645}
2646
2647// -----------------------------------------------------------------------------------------------------
2648// Printing
2649
2650#ifndef PRODUCT
2651
2652#define BULLET  " - "
2653
2654static const char* state_names[] = {
2655  "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2656};
2657
2658static void print_vtable(intptr_t* start, int len, outputStream* st) {
2659  for (int i = 0; i < len; i++) {
2660    intptr_t e = start[i];
2661    st->print("%d : " INTPTR_FORMAT, i, e);
2662    if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2663      st->print(" ");
2664      ((Metadata*)e)->print_value_on(st);
2665    }
2666    st->cr();
2667  }
2668}
2669
2670void InstanceKlass::print_on(outputStream* st) const {
2671  assert(is_klass(), "must be klass");
2672  Klass::print_on(st);
2673
2674  st->print(BULLET"instance size:     %d", size_helper());                        st->cr();
2675  st->print(BULLET"klass size:        %d", size());                               st->cr();
2676  st->print(BULLET"access:            "); access_flags().print_on(st);            st->cr();
2677  st->print(BULLET"state:             "); st->print_cr("%s", state_names[_init_state]);
2678  st->print(BULLET"name:              "); name()->print_value_on(st);             st->cr();
2679  st->print(BULLET"super:             "); super()->print_value_on_maybe_null(st); st->cr();
2680  st->print(BULLET"sub:               ");
2681  Klass* sub = subklass();
2682  int n;
2683  for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2684    if (n < MaxSubklassPrintSize) {
2685      sub->print_value_on(st);
2686      st->print("   ");
2687    }
2688  }
2689  if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2690  st->cr();
2691
2692  if (is_interface()) {
2693    st->print_cr(BULLET"nof implementors:  %d", nof_implementors());
2694    if (nof_implementors() == 1) {
2695      st->print_cr(BULLET"implementor:    ");
2696      st->print("   ");
2697      implementor()->print_value_on(st);
2698      st->cr();
2699    }
2700  }
2701
2702  st->print(BULLET"arrays:            "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2703  st->print(BULLET"methods:           "); methods()->print_value_on(st);                  st->cr();
2704  if (Verbose || WizardMode) {
2705    Array<Method*>* method_array = methods();
2706    for (int i = 0; i < method_array->length(); i++) {
2707      st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2708    }
2709  }
2710  st->print(BULLET"method ordering:   "); method_ordering()->print_value_on(st);      st->cr();
2711  st->print(BULLET"default_methods:   "); default_methods()->print_value_on(st);      st->cr();
2712  if (Verbose && default_methods() != NULL) {
2713    Array<Method*>* method_array = default_methods();
2714    for (int i = 0; i < method_array->length(); i++) {
2715      st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2716    }
2717  }
2718  if (default_vtable_indices() != NULL) {
2719    st->print(BULLET"default vtable indices:   "); default_vtable_indices()->print_value_on(st);       st->cr();
2720  }
2721  st->print(BULLET"local interfaces:  "); local_interfaces()->print_value_on(st);      st->cr();
2722  st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2723  st->print(BULLET"constants:         "); constants()->print_value_on(st);         st->cr();
2724  if (class_loader_data() != NULL) {
2725    st->print(BULLET"class loader data:  ");
2726    class_loader_data()->print_value_on(st);
2727    st->cr();
2728  }
2729  st->print(BULLET"host class:        "); host_klass()->print_value_on_maybe_null(st); st->cr();
2730  if (source_file_name() != NULL) {
2731    st->print(BULLET"source file:       ");
2732    source_file_name()->print_value_on(st);
2733    st->cr();
2734  }
2735  if (source_debug_extension() != NULL) {
2736    st->print(BULLET"source debug extension:       ");
2737    st->print("%s", source_debug_extension());
2738    st->cr();
2739  }
2740  st->print(BULLET"class annotations:       "); class_annotations()->print_value_on(st); st->cr();
2741  st->print(BULLET"class type annotations:  "); class_type_annotations()->print_value_on(st); st->cr();
2742  st->print(BULLET"field annotations:       "); fields_annotations()->print_value_on(st); st->cr();
2743  st->print(BULLET"field type annotations:  "); fields_type_annotations()->print_value_on(st); st->cr();
2744  {
2745    bool have_pv = false;
2746    // previous versions are linked together through the InstanceKlass
2747    for (InstanceKlass* pv_node = _previous_versions;
2748         pv_node != NULL;
2749         pv_node = pv_node->previous_versions()) {
2750      if (!have_pv)
2751        st->print(BULLET"previous version:  ");
2752      have_pv = true;
2753      pv_node->constants()->print_value_on(st);
2754    }
2755    if (have_pv) st->cr();
2756  }
2757
2758  if (generic_signature() != NULL) {
2759    st->print(BULLET"generic signature: ");
2760    generic_signature()->print_value_on(st);
2761    st->cr();
2762  }
2763  st->print(BULLET"inner classes:     "); inner_classes()->print_value_on(st);     st->cr();
2764  st->print(BULLET"java mirror:       "); java_mirror()->print_value_on(st);       st->cr();
2765  st->print(BULLET"vtable length      %d  (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2766  if (vtable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_vtable(), vtable_length(), st);
2767  st->print(BULLET"itable length      %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2768  if (itable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_itable(), itable_length(), st);
2769  st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2770  FieldPrinter print_static_field(st);
2771  ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2772  st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2773  FieldPrinter print_nonstatic_field(st);
2774  InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2775  ik->do_nonstatic_fields(&print_nonstatic_field);
2776
2777  st->print(BULLET"non-static oop maps: ");
2778  OopMapBlock* map     = start_of_nonstatic_oop_maps();
2779  OopMapBlock* end_map = map + nonstatic_oop_map_count();
2780  while (map < end_map) {
2781    st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2782    map++;
2783  }
2784  st->cr();
2785}
2786
2787#endif //PRODUCT
2788
2789void InstanceKlass::print_value_on(outputStream* st) const {
2790  assert(is_klass(), "must be klass");
2791  if (Verbose || WizardMode)  access_flags().print_on(st);
2792  name()->print_value_on(st);
2793}
2794
2795#ifndef PRODUCT
2796
2797void FieldPrinter::do_field(fieldDescriptor* fd) {
2798  _st->print(BULLET);
2799   if (_obj == NULL) {
2800     fd->print_on(_st);
2801     _st->cr();
2802   } else {
2803     fd->print_on_for(_st, _obj);
2804     _st->cr();
2805   }
2806}
2807
2808
2809void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2810  Klass::oop_print_on(obj, st);
2811
2812  if (this == SystemDictionary::String_klass()) {
2813    typeArrayOop value  = java_lang_String::value(obj);
2814    juint        length = java_lang_String::length(obj);
2815    if (value != NULL &&
2816        value->is_typeArray() &&
2817        length <= (juint) value->length()) {
2818      st->print(BULLET"string: ");
2819      java_lang_String::print(obj, st);
2820      st->cr();
2821      if (!WizardMode)  return;  // that is enough
2822    }
2823  }
2824
2825  st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2826  FieldPrinter print_field(st, obj);
2827  do_nonstatic_fields(&print_field);
2828
2829  if (this == SystemDictionary::Class_klass()) {
2830    st->print(BULLET"signature: ");
2831    java_lang_Class::print_signature(obj, st);
2832    st->cr();
2833    Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2834    st->print(BULLET"fake entry for mirror: ");
2835    mirrored_klass->print_value_on_maybe_null(st);
2836    st->cr();
2837    Klass* array_klass = java_lang_Class::array_klass(obj);
2838    st->print(BULLET"fake entry for array: ");
2839    array_klass->print_value_on_maybe_null(st);
2840    st->cr();
2841    st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2842    st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2843    Klass* real_klass = java_lang_Class::as_Klass(obj);
2844    if (real_klass != NULL && real_klass->is_instance_klass()) {
2845      InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2846    }
2847  } else if (this == SystemDictionary::MethodType_klass()) {
2848    st->print(BULLET"signature: ");
2849    java_lang_invoke_MethodType::print_signature(obj, st);
2850    st->cr();
2851  }
2852}
2853
2854#endif //PRODUCT
2855
2856void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2857  st->print("a ");
2858  name()->print_value_on(st);
2859  obj->print_address_on(st);
2860  if (this == SystemDictionary::String_klass()
2861      && java_lang_String::value(obj) != NULL) {
2862    ResourceMark rm;
2863    int len = java_lang_String::length(obj);
2864    int plen = (len < 24 ? len : 12);
2865    char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2866    st->print(" = \"%s\"", str);
2867    if (len > plen)
2868      st->print("...[%d]", len);
2869  } else if (this == SystemDictionary::Class_klass()) {
2870    Klass* k = java_lang_Class::as_Klass(obj);
2871    st->print(" = ");
2872    if (k != NULL) {
2873      k->print_value_on(st);
2874    } else {
2875      const char* tname = type2name(java_lang_Class::primitive_type(obj));
2876      st->print("%s", tname ? tname : "type?");
2877    }
2878  } else if (this == SystemDictionary::MethodType_klass()) {
2879    st->print(" = ");
2880    java_lang_invoke_MethodType::print_signature(obj, st);
2881  } else if (java_lang_boxing_object::is_instance(obj)) {
2882    st->print(" = ");
2883    java_lang_boxing_object::print(obj, st);
2884  } else if (this == SystemDictionary::LambdaForm_klass()) {
2885    oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
2886    if (vmentry != NULL) {
2887      st->print(" => ");
2888      vmentry->print_value_on(st);
2889    }
2890  } else if (this == SystemDictionary::MemberName_klass()) {
2891    Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
2892    if (vmtarget != NULL) {
2893      st->print(" = ");
2894      vmtarget->print_value_on(st);
2895    } else {
2896      java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
2897      st->print(".");
2898      java_lang_invoke_MemberName::name(obj)->print_value_on(st);
2899    }
2900  }
2901}
2902
2903const char* InstanceKlass::internal_name() const {
2904  return external_name();
2905}
2906
2907#if INCLUDE_SERVICES
2908// Size Statistics
2909void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
2910  Klass::collect_statistics(sz);
2911
2912  sz->_inst_size  = HeapWordSize * size_helper();
2913  sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
2914  sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
2915  sz->_nonstatic_oopmap_bytes = HeapWordSize *
2916        ((is_interface() || is_anonymous()) ?
2917         align_object_offset(nonstatic_oop_map_size()) :
2918         nonstatic_oop_map_size());
2919
2920  int n = 0;
2921  n += (sz->_methods_array_bytes         = sz->count_array(methods()));
2922  n += (sz->_method_ordering_bytes       = sz->count_array(method_ordering()));
2923  n += (sz->_local_interfaces_bytes      = sz->count_array(local_interfaces()));
2924  n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
2925  n += (sz->_fields_bytes                = sz->count_array(fields()));
2926  n += (sz->_inner_classes_bytes         = sz->count_array(inner_classes()));
2927  sz->_ro_bytes += n;
2928
2929  const ConstantPool* cp = constants();
2930  if (cp) {
2931    cp->collect_statistics(sz);
2932  }
2933
2934  const Annotations* anno = annotations();
2935  if (anno) {
2936    anno->collect_statistics(sz);
2937  }
2938
2939  const Array<Method*>* methods_array = methods();
2940  if (methods()) {
2941    for (int i = 0; i < methods_array->length(); i++) {
2942      Method* method = methods_array->at(i);
2943      if (method) {
2944        sz->_method_count ++;
2945        method->collect_statistics(sz);
2946      }
2947    }
2948  }
2949}
2950#endif // INCLUDE_SERVICES
2951
2952// Verification
2953
2954class VerifyFieldClosure: public OopClosure {
2955 protected:
2956  template <class T> void do_oop_work(T* p) {
2957    oop obj = oopDesc::load_decode_heap_oop(p);
2958    if (!obj->is_oop_or_null()) {
2959      tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
2960      Universe::print_on(tty);
2961      guarantee(false, "boom");
2962    }
2963  }
2964 public:
2965  virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
2966  virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2967};
2968
2969void InstanceKlass::verify_on(outputStream* st) {
2970#ifndef PRODUCT
2971  // Avoid redundant verifies, this really should be in product.
2972  if (_verify_count == Universe::verify_count()) return;
2973  _verify_count = Universe::verify_count();
2974#endif
2975
2976  // Verify Klass
2977  Klass::verify_on(st);
2978
2979  // Verify that klass is present in ClassLoaderData
2980  guarantee(class_loader_data()->contains_klass(this),
2981            "this class isn't found in class loader data");
2982
2983  // Verify vtables
2984  if (is_linked()) {
2985    ResourceMark rm;
2986    // $$$ This used to be done only for m/s collections.  Doing it
2987    // always seemed a valid generalization.  (DLD -- 6/00)
2988    vtable()->verify(st);
2989  }
2990
2991  // Verify first subklass
2992  if (subklass() != NULL) {
2993    guarantee(subklass()->is_klass(), "should be klass");
2994  }
2995
2996  // Verify siblings
2997  Klass* super = this->super();
2998  Klass* sib = next_sibling();
2999  if (sib != NULL) {
3000    if (sib == this) {
3001      fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3002    }
3003
3004    guarantee(sib->is_klass(), "should be klass");
3005    guarantee(sib->super() == super, "siblings should have same superklass");
3006  }
3007
3008  // Verify implementor fields
3009  Klass* im = implementor();
3010  if (im != NULL) {
3011    guarantee(is_interface(), "only interfaces should have implementor set");
3012    guarantee(im->is_klass(), "should be klass");
3013    guarantee(!im->is_interface() || im == this,
3014      "implementors cannot be interfaces");
3015  }
3016
3017  // Verify local interfaces
3018  if (local_interfaces()) {
3019    Array<Klass*>* local_interfaces = this->local_interfaces();
3020    for (int j = 0; j < local_interfaces->length(); j++) {
3021      Klass* e = local_interfaces->at(j);
3022      guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3023    }
3024  }
3025
3026  // Verify transitive interfaces
3027  if (transitive_interfaces() != NULL) {
3028    Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3029    for (int j = 0; j < transitive_interfaces->length(); j++) {
3030      Klass* e = transitive_interfaces->at(j);
3031      guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3032    }
3033  }
3034
3035  // Verify methods
3036  if (methods() != NULL) {
3037    Array<Method*>* methods = this->methods();
3038    for (int j = 0; j < methods->length(); j++) {
3039      guarantee(methods->at(j)->is_method(), "non-method in methods array");
3040    }
3041    for (int j = 0; j < methods->length() - 1; j++) {
3042      Method* m1 = methods->at(j);
3043      Method* m2 = methods->at(j + 1);
3044      guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3045    }
3046  }
3047
3048  // Verify method ordering
3049  if (method_ordering() != NULL) {
3050    Array<int>* method_ordering = this->method_ordering();
3051    int length = method_ordering->length();
3052    if (JvmtiExport::can_maintain_original_method_order() ||
3053        ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3054      guarantee(length == methods()->length(), "invalid method ordering length");
3055      jlong sum = 0;
3056      for (int j = 0; j < length; j++) {
3057        int original_index = method_ordering->at(j);
3058        guarantee(original_index >= 0, "invalid method ordering index");
3059        guarantee(original_index < length, "invalid method ordering index");
3060        sum += original_index;
3061      }
3062      // Verify sum of indices 0,1,...,length-1
3063      guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3064    } else {
3065      guarantee(length == 0, "invalid method ordering length");
3066    }
3067  }
3068
3069  // Verify default methods
3070  if (default_methods() != NULL) {
3071    Array<Method*>* methods = this->default_methods();
3072    for (int j = 0; j < methods->length(); j++) {
3073      guarantee(methods->at(j)->is_method(), "non-method in methods array");
3074    }
3075    for (int j = 0; j < methods->length() - 1; j++) {
3076      Method* m1 = methods->at(j);
3077      Method* m2 = methods->at(j + 1);
3078      guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3079    }
3080  }
3081
3082  // Verify JNI static field identifiers
3083  if (jni_ids() != NULL) {
3084    jni_ids()->verify(this);
3085  }
3086
3087  // Verify other fields
3088  if (array_klasses() != NULL) {
3089    guarantee(array_klasses()->is_klass(), "should be klass");
3090  }
3091  if (constants() != NULL) {
3092    guarantee(constants()->is_constantPool(), "should be constant pool");
3093  }
3094  const Klass* host = host_klass();
3095  if (host != NULL) {
3096    guarantee(host->is_klass(), "should be klass");
3097  }
3098}
3099
3100void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3101  Klass::oop_verify_on(obj, st);
3102  VerifyFieldClosure blk;
3103  obj->oop_iterate_no_header(&blk);
3104}
3105
3106
3107// JNIid class for jfieldIDs only
3108// Note to reviewers:
3109// These JNI functions are just moved over to column 1 and not changed
3110// in the compressed oops workspace.
3111JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3112  _holder = holder;
3113  _offset = offset;
3114  _next = next;
3115  debug_only(_is_static_field_id = false;)
3116}
3117
3118
3119JNIid* JNIid::find(int offset) {
3120  JNIid* current = this;
3121  while (current != NULL) {
3122    if (current->offset() == offset) return current;
3123    current = current->next();
3124  }
3125  return NULL;
3126}
3127
3128void JNIid::deallocate(JNIid* current) {
3129  while (current != NULL) {
3130    JNIid* next = current->next();
3131    delete current;
3132    current = next;
3133  }
3134}
3135
3136
3137void JNIid::verify(Klass* holder) {
3138  int first_field_offset  = InstanceMirrorKlass::offset_of_static_fields();
3139  int end_field_offset;
3140  end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3141
3142  JNIid* current = this;
3143  while (current != NULL) {
3144    guarantee(current->holder() == holder, "Invalid klass in JNIid");
3145#ifdef ASSERT
3146    int o = current->offset();
3147    if (current->is_static_field_id()) {
3148      guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
3149    }
3150#endif
3151    current = current->next();
3152  }
3153}
3154
3155
3156#ifdef ASSERT
3157void InstanceKlass::set_init_state(ClassState state) {
3158  bool good_state = is_shared() ? (_init_state <= state)
3159                                               : (_init_state < state);
3160  assert(good_state || state == allocated, "illegal state transition");
3161  _init_state = (u1)state;
3162}
3163#endif
3164
3165
3166
3167// RedefineClasses() support for previous versions:
3168int InstanceKlass::_previous_version_count = 0;
3169
3170// Purge previous versions before adding new previous versions of the class.
3171void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3172  if (ik->previous_versions() != NULL) {
3173    // This klass has previous versions so see what we can cleanup
3174    // while it is safe to do so.
3175
3176    int deleted_count = 0;    // leave debugging breadcrumbs
3177    int live_count = 0;
3178    ClassLoaderData* loader_data = ik->class_loader_data();
3179    assert(loader_data != NULL, "should never be null");
3180
3181    // RC_TRACE macro has an embedded ResourceMark
3182    RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name()));
3183
3184    // previous versions are linked together through the InstanceKlass
3185    InstanceKlass* pv_node = ik->previous_versions();
3186    InstanceKlass* last = ik;
3187    int version = 0;
3188
3189    // check the previous versions list
3190    for (; pv_node != NULL; ) {
3191
3192      ConstantPool* pvcp = pv_node->constants();
3193      assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3194
3195      if (!pvcp->on_stack()) {
3196        // If the constant pool isn't on stack, none of the methods
3197        // are executing.  Unlink this previous_version.
3198        // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3199        // so will be deallocated during the next phase of class unloading.
3200        RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead",
3201                              p2i(pv_node)));
3202        // For debugging purposes.
3203        pv_node->set_is_scratch_class();
3204        pv_node->class_loader_data()->add_to_deallocate_list(pv_node);
3205        pv_node = pv_node->previous_versions();
3206        last->link_previous_versions(pv_node);
3207        deleted_count++;
3208        version++;
3209        continue;
3210      } else {
3211        RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive",
3212                              p2i(pv_node)));
3213        assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3214        guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3215        live_count++;
3216      }
3217
3218      // At least one method is live in this previous version.
3219      // Reset dead EMCP methods not to get breakpoints.
3220      // All methods are deallocated when all of the methods for this class are no
3221      // longer running.
3222      Array<Method*>* method_refs = pv_node->methods();
3223      if (method_refs != NULL) {
3224        RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3225          method_refs->length()));
3226        for (int j = 0; j < method_refs->length(); j++) {
3227          Method* method = method_refs->at(j);
3228
3229          if (!method->on_stack()) {
3230            // no breakpoints for non-running methods
3231            if (method->is_running_emcp()) {
3232              method->set_running_emcp(false);
3233            }
3234          } else {
3235            assert (method->is_obsolete() || method->is_running_emcp(),
3236                    "emcp method cannot run after emcp bit is cleared");
3237            // RC_TRACE macro has an embedded ResourceMark
3238            RC_TRACE(0x00000200,
3239              ("purge: %s(%s): prev method @%d in version @%d is alive",
3240              method->name()->as_C_string(),
3241              method->signature()->as_C_string(), j, version));
3242          }
3243        }
3244      }
3245      // next previous version
3246      last = pv_node;
3247      pv_node = pv_node->previous_versions();
3248      version++;
3249    }
3250    RC_TRACE(0x00000200,
3251      ("purge: previous version stats: live=%d, deleted=%d", live_count,
3252      deleted_count));
3253  }
3254}
3255
3256void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3257                                                int emcp_method_count) {
3258  int obsolete_method_count = old_methods->length() - emcp_method_count;
3259
3260  if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3261      _previous_versions != NULL) {
3262    // We have a mix of obsolete and EMCP methods so we have to
3263    // clear out any matching EMCP method entries the hard way.
3264    int local_count = 0;
3265    for (int i = 0; i < old_methods->length(); i++) {
3266      Method* old_method = old_methods->at(i);
3267      if (old_method->is_obsolete()) {
3268        // only obsolete methods are interesting
3269        Symbol* m_name = old_method->name();
3270        Symbol* m_signature = old_method->signature();
3271
3272        // previous versions are linked together through the InstanceKlass
3273        int j = 0;
3274        for (InstanceKlass* prev_version = _previous_versions;
3275             prev_version != NULL;
3276             prev_version = prev_version->previous_versions(), j++) {
3277
3278          Array<Method*>* method_refs = prev_version->methods();
3279          for (int k = 0; k < method_refs->length(); k++) {
3280            Method* method = method_refs->at(k);
3281
3282            if (!method->is_obsolete() &&
3283                method->name() == m_name &&
3284                method->signature() == m_signature) {
3285              // The current RedefineClasses() call has made all EMCP
3286              // versions of this method obsolete so mark it as obsolete
3287              RC_TRACE(0x00000400,
3288                ("add: %s(%s): flush obsolete method @%d in version @%d",
3289                m_name->as_C_string(), m_signature->as_C_string(), k, j));
3290
3291              method->set_is_obsolete();
3292              break;
3293            }
3294          }
3295
3296          // The previous loop may not find a matching EMCP method, but
3297          // that doesn't mean that we can optimize and not go any
3298          // further back in the PreviousVersion generations. The EMCP
3299          // method for this generation could have already been made obsolete,
3300          // but there still may be an older EMCP method that has not
3301          // been made obsolete.
3302        }
3303
3304        if (++local_count >= obsolete_method_count) {
3305          // no more obsolete methods so bail out now
3306          break;
3307        }
3308      }
3309    }
3310  }
3311}
3312
3313// Save the scratch_class as the previous version if any of the methods are running.
3314// The previous_versions are used to set breakpoints in EMCP methods and they are
3315// also used to clean MethodData links to redefined methods that are no longer running.
3316void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class,
3317                                         int emcp_method_count) {
3318  assert(Thread::current()->is_VM_thread(),
3319         "only VMThread can add previous versions");
3320
3321  // RC_TRACE macro has an embedded ResourceMark
3322  RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d",
3323    scratch_class->external_name(), emcp_method_count));
3324
3325  // Clean out old previous versions
3326  purge_previous_versions(this);
3327
3328  // Mark newly obsolete methods in remaining previous versions.  An EMCP method from
3329  // a previous redefinition may be made obsolete by this redefinition.
3330  Array<Method*>* old_methods = scratch_class->methods();
3331  mark_newly_obsolete_methods(old_methods, emcp_method_count);
3332
3333  // If the constant pool for this previous version of the class
3334  // is not marked as being on the stack, then none of the methods
3335  // in this previous version of the class are on the stack so
3336  // we don't need to add this as a previous version.
3337  ConstantPool* cp_ref = scratch_class->constants();
3338  if (!cp_ref->on_stack()) {
3339    RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running"));
3340    // For debugging purposes.
3341    scratch_class->set_is_scratch_class();
3342    scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class());
3343    // Update count for class unloading.
3344    _previous_version_count--;
3345    return;
3346  }
3347
3348  if (emcp_method_count != 0) {
3349    // At least one method is still running, check for EMCP methods
3350    for (int i = 0; i < old_methods->length(); i++) {
3351      Method* old_method = old_methods->at(i);
3352      if (!old_method->is_obsolete() && old_method->on_stack()) {
3353        // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3354        // we can add breakpoints for it.
3355
3356        // We set the method->on_stack bit during safepoints for class redefinition
3357        // and use this bit to set the is_running_emcp bit.
3358        // After the safepoint, the on_stack bit is cleared and the running emcp
3359        // method may exit.   If so, we would set a breakpoint in a method that
3360        // is never reached, but this won't be noticeable to the programmer.
3361        old_method->set_running_emcp(true);
3362        RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT,
3363                              old_method->name_and_sig_as_C_string(), p2i(old_method)));
3364      } else if (!old_method->is_obsolete()) {
3365        RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT,
3366                              old_method->name_and_sig_as_C_string(), p2i(old_method)));
3367      }
3368    }
3369  }
3370
3371  // Add previous version if any methods are still running.
3372  RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack"));
3373  assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3374  scratch_class->link_previous_versions(previous_versions());
3375  link_previous_versions(scratch_class());
3376  // Update count for class unloading.
3377  _previous_version_count++;
3378} // end add_previous_version()
3379
3380
3381Method* InstanceKlass::method_with_idnum(int idnum) {
3382  Method* m = NULL;
3383  if (idnum < methods()->length()) {
3384    m = methods()->at(idnum);
3385  }
3386  if (m == NULL || m->method_idnum() != idnum) {
3387    for (int index = 0; index < methods()->length(); ++index) {
3388      m = methods()->at(index);
3389      if (m->method_idnum() == idnum) {
3390        return m;
3391      }
3392    }
3393    // None found, return null for the caller to handle.
3394    return NULL;
3395  }
3396  return m;
3397}
3398
3399
3400Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3401  if (idnum >= methods()->length()) {
3402    return NULL;
3403  }
3404  Method* m = methods()->at(idnum);
3405  if (m != NULL && m->orig_method_idnum() == idnum) {
3406    return m;
3407  }
3408  // Obsolete method idnum does not match the original idnum
3409  for (int index = 0; index < methods()->length(); ++index) {
3410    m = methods()->at(index);
3411    if (m->orig_method_idnum() == idnum) {
3412      return m;
3413    }
3414  }
3415  // None found, return null for the caller to handle.
3416  return NULL;
3417}
3418
3419
3420Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3421  InstanceKlass* holder = get_klass_version(version);
3422  if (holder == NULL) {
3423    return NULL; // The version of klass is gone, no method is found
3424  }
3425  Method* method = holder->method_with_orig_idnum(idnum);
3426  return method;
3427}
3428
3429
3430jint InstanceKlass::get_cached_class_file_len() {
3431  return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3432}
3433
3434unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3435  return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3436}
3437