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--- old/src/share/vm/classfile/systemDictionary.cpp
+++ new/src/share/vm/classfile/systemDictionary.cpp
1 1 /*
2 2 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
3 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 4 *
5 5 * This code is free software; you can redistribute it and/or modify it
6 6 * under the terms of the GNU General Public License version 2 only, as
7 7 * published by the Free Software Foundation.
8 8 *
9 9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 12 * version 2 for more details (a copy is included in the LICENSE file that
13 13 * accompanied this code).
14 14 *
15 15 * You should have received a copy of the GNU General Public License version
16 16 * 2 along with this work; if not, write to the Free Software Foundation,
17 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 18 *
19 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 20 * or visit www.oracle.com if you need additional information or have any
21 21 * questions.
22 22 *
23 23 */
24 24
25 25 #include "precompiled.hpp"
26 26 #include "classfile/dictionary.hpp"
27 27 #include "classfile/javaClasses.hpp"
28 28 #include "classfile/loaderConstraints.hpp"
29 29 #include "classfile/placeholders.hpp"
30 30 #include "classfile/resolutionErrors.hpp"
31 31 #include "classfile/systemDictionary.hpp"
32 32 #include "classfile/vmSymbols.hpp"
33 33 #include "interpreter/bytecodeStream.hpp"
34 34 #include "interpreter/interpreter.hpp"
35 35 #include "memory/gcLocker.hpp"
36 36 #include "memory/oopFactory.hpp"
37 37 #include "oops/instanceKlass.hpp"
38 38 #include "oops/instanceRefKlass.hpp"
39 39 #include "oops/klass.inline.hpp"
40 40 #include "oops/methodDataOop.hpp"
41 41 #include "oops/objArrayKlass.hpp"
42 42 #include "oops/oop.inline.hpp"
43 43 #include "oops/oop.inline2.hpp"
44 44 #include "oops/typeArrayKlass.hpp"
45 45 #include "prims/jvmtiEnvBase.hpp"
46 46 #include "prims/methodHandles.hpp"
47 47 #include "runtime/biasedLocking.hpp"
48 48 #include "runtime/fieldType.hpp"
49 49 #include "runtime/handles.inline.hpp"
50 50 #include "runtime/java.hpp"
51 51 #include "runtime/javaCalls.hpp"
52 52 #include "runtime/mutexLocker.hpp"
53 53 #include "runtime/signature.hpp"
54 54 #include "services/classLoadingService.hpp"
55 55 #include "services/threadService.hpp"
56 56
57 57
58 58 Dictionary* SystemDictionary::_dictionary = NULL;
59 59 PlaceholderTable* SystemDictionary::_placeholders = NULL;
60 60 Dictionary* SystemDictionary::_shared_dictionary = NULL;
61 61 LoaderConstraintTable* SystemDictionary::_loader_constraints = NULL;
62 62 ResolutionErrorTable* SystemDictionary::_resolution_errors = NULL;
63 63 SymbolPropertyTable* SystemDictionary::_invoke_method_table = NULL;
64 64
65 65
66 66 int SystemDictionary::_number_of_modifications = 0;
67 67
68 68 oop SystemDictionary::_system_loader_lock_obj = NULL;
69 69
70 70 klassOop SystemDictionary::_well_known_klasses[SystemDictionary::WKID_LIMIT]
71 71 = { NULL /*, NULL...*/ };
72 72
73 73 klassOop SystemDictionary::_box_klasses[T_VOID+1] = { NULL /*, NULL...*/ };
74 74
75 75 oop SystemDictionary::_java_system_loader = NULL;
76 76
77 77 bool SystemDictionary::_has_loadClassInternal = false;
78 78 bool SystemDictionary::_has_checkPackageAccess = false;
79 79
80 80 // lazily initialized klass variables
81 81 volatile klassOop SystemDictionary::_abstract_ownable_synchronizer_klass = NULL;
82 82
83 83
84 84 // ----------------------------------------------------------------------------
85 85 // Java-level SystemLoader
86 86
87 87 oop SystemDictionary::java_system_loader() {
88 88 return _java_system_loader;
89 89 }
90 90
91 91 void SystemDictionary::compute_java_system_loader(TRAPS) {
92 92 KlassHandle system_klass(THREAD, WK_KLASS(ClassLoader_klass));
93 93 JavaValue result(T_OBJECT);
94 94 JavaCalls::call_static(&result,
95 95 KlassHandle(THREAD, WK_KLASS(ClassLoader_klass)),
96 96 vmSymbols::getSystemClassLoader_name(),
97 97 vmSymbols::void_classloader_signature(),
98 98 CHECK);
99 99
100 100 _java_system_loader = (oop)result.get_jobject();
101 101 }
102 102
103 103
104 104 // ----------------------------------------------------------------------------
105 105 // debugging
106 106
107 107 #ifdef ASSERT
108 108
109 109 // return true if class_name contains no '.' (internal format is '/')
110 110 bool SystemDictionary::is_internal_format(Symbol* class_name) {
111 111 if (class_name != NULL) {
112 112 ResourceMark rm;
113 113 char* name = class_name->as_C_string();
114 114 return strchr(name, '.') == NULL;
115 115 } else {
116 116 return true;
117 117 }
118 118 }
119 119
120 120 #endif
121 121
122 122 // ----------------------------------------------------------------------------
123 123 // Parallel class loading check
124 124
125 125 bool SystemDictionary::is_parallelCapable(Handle class_loader) {
126 126 if (UnsyncloadClass || class_loader.is_null()) return true;
127 127 if (AlwaysLockClassLoader) return false;
128 128 return java_lang_Class::parallelCapable(class_loader());
129 129 }
130 130 // ----------------------------------------------------------------------------
131 131 // ParallelDefineClass flag does not apply to bootclass loader
132 132 bool SystemDictionary::is_parallelDefine(Handle class_loader) {
133 133 if (class_loader.is_null()) return false;
134 134 if (AllowParallelDefineClass && java_lang_Class::parallelCapable(class_loader())) {
135 135 return true;
136 136 }
137 137 return false;
138 138 }
139 139 // ----------------------------------------------------------------------------
140 140 // Resolving of classes
141 141
142 142 // Forwards to resolve_or_null
143 143
144 144 klassOop SystemDictionary::resolve_or_fail(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS) {
145 145 klassOop klass = resolve_or_null(class_name, class_loader, protection_domain, THREAD);
146 146 if (HAS_PENDING_EXCEPTION || klass == NULL) {
147 147 KlassHandle k_h(THREAD, klass);
148 148 // can return a null klass
149 149 klass = handle_resolution_exception(class_name, class_loader, protection_domain, throw_error, k_h, THREAD);
150 150 }
151 151 return klass;
152 152 }
153 153
154 154 klassOop SystemDictionary::handle_resolution_exception(Symbol* class_name, Handle class_loader, Handle protection_domain, bool throw_error, KlassHandle klass_h, TRAPS) {
155 155 if (HAS_PENDING_EXCEPTION) {
156 156 // If we have a pending exception we forward it to the caller, unless throw_error is true,
157 157 // in which case we have to check whether the pending exception is a ClassNotFoundException,
158 158 // and if so convert it to a NoClassDefFoundError
159 159 // And chain the original ClassNotFoundException
160 160 if (throw_error && PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass())) {
161 161 ResourceMark rm(THREAD);
162 162 assert(klass_h() == NULL, "Should not have result with exception pending");
163 163 Handle e(THREAD, PENDING_EXCEPTION);
164 164 CLEAR_PENDING_EXCEPTION;
165 165 THROW_MSG_CAUSE_0(vmSymbols::java_lang_NoClassDefFoundError(), class_name->as_C_string(), e);
166 166 } else {
167 167 return NULL;
168 168 }
169 169 }
170 170 // Class not found, throw appropriate error or exception depending on value of throw_error
171 171 if (klass_h() == NULL) {
172 172 ResourceMark rm(THREAD);
173 173 if (throw_error) {
174 174 THROW_MSG_0(vmSymbols::java_lang_NoClassDefFoundError(), class_name->as_C_string());
175 175 } else {
176 176 THROW_MSG_0(vmSymbols::java_lang_ClassNotFoundException(), class_name->as_C_string());
177 177 }
178 178 }
179 179 return (klassOop)klass_h();
180 180 }
181 181
182 182
183 183 klassOop SystemDictionary::resolve_or_fail(Symbol* class_name,
184 184 bool throw_error, TRAPS)
185 185 {
186 186 return resolve_or_fail(class_name, Handle(), Handle(), throw_error, THREAD);
187 187 }
188 188
189 189
190 190 // Forwards to resolve_instance_class_or_null
191 191
192 192 klassOop SystemDictionary::resolve_or_null(Symbol* class_name, Handle class_loader, Handle protection_domain, TRAPS) {
193 193 assert(!THREAD->is_Compiler_thread(), "Can not load classes with the Compiler thread");
194 194 if (FieldType::is_array(class_name)) {
195 195 return resolve_array_class_or_null(class_name, class_loader, protection_domain, CHECK_NULL);
196 196 } else if (FieldType::is_obj(class_name)) {
197 197 ResourceMark rm(THREAD);
198 198 // Ignore wrapping L and ;.
199 199 TempNewSymbol name = SymbolTable::new_symbol(class_name->as_C_string() + 1,
200 200 class_name->utf8_length() - 2, CHECK_NULL);
201 201 return resolve_instance_class_or_null(name, class_loader, protection_domain, CHECK_NULL);
202 202 } else {
203 203 return resolve_instance_class_or_null(class_name, class_loader, protection_domain, CHECK_NULL);
204 204 }
205 205 }
206 206
207 207 klassOop SystemDictionary::resolve_or_null(Symbol* class_name, TRAPS) {
208 208 return resolve_or_null(class_name, Handle(), Handle(), THREAD);
209 209 }
210 210
211 211 // Forwards to resolve_instance_class_or_null
212 212
213 213 klassOop SystemDictionary::resolve_array_class_or_null(Symbol* class_name,
214 214 Handle class_loader,
215 215 Handle protection_domain,
216 216 TRAPS) {
217 217 assert(FieldType::is_array(class_name), "must be array");
218 218 klassOop k = NULL;
219 219 FieldArrayInfo fd;
220 220 // dimension and object_key in FieldArrayInfo are assigned as a side-effect
221 221 // of this call
222 222 BasicType t = FieldType::get_array_info(class_name, fd, CHECK_NULL);
223 223 if (t == T_OBJECT) {
224 224 // naked oop "k" is OK here -- we assign back into it
225 225 k = SystemDictionary::resolve_instance_class_or_null(fd.object_key(),
226 226 class_loader,
227 227 protection_domain,
228 228 CHECK_NULL);
229 229 if (k != NULL) {
230 230 k = Klass::cast(k)->array_klass(fd.dimension(), CHECK_NULL);
231 231 }
232 232 } else {
233 233 k = Universe::typeArrayKlassObj(t);
234 234 k = typeArrayKlass::cast(k)->array_klass(fd.dimension(), CHECK_NULL);
235 235 }
236 236 return k;
237 237 }
238 238
239 239
240 240 // Must be called for any super-class or super-interface resolution
241 241 // during class definition to allow class circularity checking
242 242 // super-interface callers:
243 243 // parse_interfaces - for defineClass & jvmtiRedefineClasses
244 244 // super-class callers:
245 245 // ClassFileParser - for defineClass & jvmtiRedefineClasses
246 246 // load_shared_class - while loading a class from shared archive
247 247 // resolve_instance_class_or_null:
248 248 // via: handle_parallel_super_load
249 249 // when resolving a class that has an existing placeholder with
250 250 // a saved superclass [i.e. a defineClass is currently in progress]
251 251 // if another thread is trying to resolve the class, it must do
252 252 // super-class checks on its own thread to catch class circularity
253 253 // This last call is critical in class circularity checking for cases
254 254 // where classloading is delegated to different threads and the
255 255 // classloader lock is released.
256 256 // Take the case: Base->Super->Base
257 257 // 1. If thread T1 tries to do a defineClass of class Base
258 258 // resolve_super_or_fail creates placeholder: T1, Base (super Super)
259 259 // 2. resolve_instance_class_or_null does not find SD or placeholder for Super
260 260 // so it tries to load Super
261 261 // 3. If we load the class internally, or user classloader uses same thread
262 262 // loadClassFromxxx or defineClass via parseClassFile Super ...
263 263 // 3.1 resolve_super_or_fail creates placeholder: T1, Super (super Base)
264 264 // 3.3 resolve_instance_class_or_null Base, finds placeholder for Base
265 265 // 3.4 calls resolve_super_or_fail Base
266 266 // 3.5 finds T1,Base -> throws class circularity
267 267 //OR 4. If T2 tries to resolve Super via defineClass Super ...
268 268 // 4.1 resolve_super_or_fail creates placeholder: T2, Super (super Base)
269 269 // 4.2 resolve_instance_class_or_null Base, finds placeholder for Base (super Super)
270 270 // 4.3 calls resolve_super_or_fail Super in parallel on own thread T2
271 271 // 4.4 finds T2, Super -> throws class circularity
272 272 // Must be called, even if superclass is null, since this is
273 273 // where the placeholder entry is created which claims this
274 274 // thread is loading this class/classloader.
275 275 klassOop SystemDictionary::resolve_super_or_fail(Symbol* child_name,
276 276 Symbol* class_name,
277 277 Handle class_loader,
278 278 Handle protection_domain,
279 279 bool is_superclass,
280 280 TRAPS) {
281 281
282 282 // Try to get one of the well-known klasses.
283 283 // They are trusted, and do not participate in circularities.
284 284 if (LinkWellKnownClasses) {
285 285 klassOop k = find_well_known_klass(class_name);
286 286 if (k != NULL) {
287 287 return k;
288 288 }
289 289 }
290 290
291 291 // Double-check, if child class is already loaded, just return super-class,interface
292 292 // Don't add a placedholder if already loaded, i.e. already in system dictionary
293 293 // Make sure there's a placeholder for the *child* before resolving.
294 294 // Used as a claim that this thread is currently loading superclass/classloader
295 295 // Used here for ClassCircularity checks and also for heap verification
296 296 // (every instanceKlass in the heap needs to be in the system dictionary
297 297 // or have a placeholder).
298 298 // Must check ClassCircularity before checking if super class is already loaded
299 299 //
300 300 // We might not already have a placeholder if this child_name was
301 301 // first seen via resolve_from_stream (jni_DefineClass or JVM_DefineClass);
302 302 // the name of the class might not be known until the stream is actually
303 303 // parsed.
304 304 // Bugs 4643874, 4715493
305 305 // compute_hash can have a safepoint
306 306
307 307 unsigned int d_hash = dictionary()->compute_hash(child_name, class_loader);
308 308 int d_index = dictionary()->hash_to_index(d_hash);
309 309 unsigned int p_hash = placeholders()->compute_hash(child_name, class_loader);
310 310 int p_index = placeholders()->hash_to_index(p_hash);
311 311 // can't throw error holding a lock
312 312 bool child_already_loaded = false;
313 313 bool throw_circularity_error = false;
314 314 {
315 315 MutexLocker mu(SystemDictionary_lock, THREAD);
316 316 klassOop childk = find_class(d_index, d_hash, child_name, class_loader);
317 317 klassOop quicksuperk;
318 318 // to support // loading: if child done loading, just return superclass
319 319 // if class_name, & class_loader don't match:
320 320 // if initial define, SD update will give LinkageError
321 321 // if redefine: compare_class_versions will give HIERARCHY_CHANGED
322 322 // so we don't throw an exception here.
323 323 // see: nsk redefclass014 & java.lang.instrument Instrument032
324 324 if ((childk != NULL ) && (is_superclass) &&
325 325 ((quicksuperk = instanceKlass::cast(childk)->super()) != NULL) &&
326 326
327 327 ((Klass::cast(quicksuperk)->name() == class_name) &&
328 328 (Klass::cast(quicksuperk)->class_loader() == class_loader()))) {
329 329 return quicksuperk;
330 330 } else {
331 331 PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, child_name, class_loader);
332 332 if (probe && probe->check_seen_thread(THREAD, PlaceholderTable::LOAD_SUPER)) {
333 333 throw_circularity_error = true;
334 334 }
335 335 }
336 336 if (!throw_circularity_error) {
337 337 PlaceholderEntry* newprobe = placeholders()->find_and_add(p_index, p_hash, child_name, class_loader, PlaceholderTable::LOAD_SUPER, class_name, THREAD);
338 338 }
339 339 }
340 340 if (throw_circularity_error) {
341 341 ResourceMark rm(THREAD);
342 342 THROW_MSG_0(vmSymbols::java_lang_ClassCircularityError(), child_name->as_C_string());
343 343 }
344 344
345 345 // java.lang.Object should have been found above
346 346 assert(class_name != NULL, "null super class for resolving");
347 347 // Resolve the super class or interface, check results on return
348 348 klassOop superk = NULL;
349 349 superk = SystemDictionary::resolve_or_null(class_name,
350 350 class_loader,
351 351 protection_domain,
352 352 THREAD);
353 353
354 354 KlassHandle superk_h(THREAD, superk);
355 355
356 356 // Note: clean up of placeholders currently in callers of
357 357 // resolve_super_or_fail - either at update_dictionary time
358 358 // or on error
359 359 {
360 360 MutexLocker mu(SystemDictionary_lock, THREAD);
361 361 PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, child_name, class_loader);
362 362 if (probe != NULL) {
363 363 probe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_SUPER);
364 364 }
365 365 }
366 366 if (HAS_PENDING_EXCEPTION || superk_h() == NULL) {
367 367 // can null superk
368 368 superk_h = KlassHandle(THREAD, handle_resolution_exception(class_name, class_loader, protection_domain, true, superk_h, THREAD));
369 369 }
370 370
371 371 return superk_h();
372 372 }
373 373
374 374 void SystemDictionary::validate_protection_domain(instanceKlassHandle klass,
375 375 Handle class_loader,
376 376 Handle protection_domain,
377 377 TRAPS) {
378 378 if(!has_checkPackageAccess()) return;
379 379
380 380 // Now we have to call back to java to check if the initating class has access
381 381 JavaValue result(T_VOID);
382 382 if (TraceProtectionDomainVerification) {
383 383 // Print out trace information
384 384 tty->print_cr("Checking package access");
385 385 tty->print(" - class loader: "); class_loader()->print_value_on(tty); tty->cr();
386 386 tty->print(" - protection domain: "); protection_domain()->print_value_on(tty); tty->cr();
387 387 tty->print(" - loading: "); klass()->print_value_on(tty); tty->cr();
388 388 }
389 389
390 390 assert(class_loader() != NULL, "should not have non-null protection domain for null classloader");
391 391
392 392 KlassHandle system_loader(THREAD, SystemDictionary::ClassLoader_klass());
393 393 JavaCalls::call_special(&result,
394 394 class_loader,
395 395 system_loader,
396 396 vmSymbols::checkPackageAccess_name(),
397 397 vmSymbols::class_protectiondomain_signature(),
398 398 Handle(THREAD, klass->java_mirror()),
399 399 protection_domain,
400 400 THREAD);
401 401
402 402 if (TraceProtectionDomainVerification) {
403 403 if (HAS_PENDING_EXCEPTION) {
404 404 tty->print_cr(" -> DENIED !!!!!!!!!!!!!!!!!!!!!");
405 405 } else {
406 406 tty->print_cr(" -> granted");
407 407 }
408 408 tty->cr();
409 409 }
410 410
411 411 if (HAS_PENDING_EXCEPTION) return;
412 412
413 413 // If no exception has been thrown, we have validated the protection domain
414 414 // Insert the protection domain of the initiating class into the set.
415 415 {
416 416 // We recalculate the entry here -- we've called out to java since
417 417 // the last time it was calculated.
418 418 Symbol* kn = klass->name();
419 419 unsigned int d_hash = dictionary()->compute_hash(kn, class_loader);
420 420 int d_index = dictionary()->hash_to_index(d_hash);
421 421
422 422 MutexLocker mu(SystemDictionary_lock, THREAD);
423 423 {
424 424 // Note that we have an entry, and entries can be deleted only during GC,
425 425 // so we cannot allow GC to occur while we're holding this entry.
426 426
427 427 // We're using a No_Safepoint_Verifier to catch any place where we
428 428 // might potentially do a GC at all.
429 429 // SystemDictionary::do_unloading() asserts that classes are only
430 430 // unloaded at a safepoint.
431 431 No_Safepoint_Verifier nosafepoint;
432 432 dictionary()->add_protection_domain(d_index, d_hash, klass, class_loader,
433 433 protection_domain, THREAD);
434 434 }
435 435 }
436 436 }
437 437
438 438 // We only get here if this thread finds that another thread
439 439 // has already claimed the placeholder token for the current operation,
440 440 // but that other thread either never owned or gave up the
441 441 // object lock
442 442 // Waits on SystemDictionary_lock to indicate placeholder table updated
443 443 // On return, caller must recheck placeholder table state
444 444 //
445 445 // We only get here if
446 446 // 1) custom classLoader, i.e. not bootstrap classloader
447 447 // 2) UnsyncloadClass not set
448 448 // 3) custom classLoader has broken the class loader objectLock
449 449 // so another thread got here in parallel
450 450 //
451 451 // lockObject must be held.
452 452 // Complicated dance due to lock ordering:
453 453 // Must first release the classloader object lock to
454 454 // allow initial definer to complete the class definition
455 455 // and to avoid deadlock
456 456 // Reclaim classloader lock object with same original recursion count
457 457 // Must release SystemDictionary_lock after notify, since
458 458 // class loader lock must be claimed before SystemDictionary_lock
459 459 // to prevent deadlocks
460 460 //
461 461 // The notify allows applications that did an untimed wait() on
462 462 // the classloader object lock to not hang.
463 463 void SystemDictionary::double_lock_wait(Handle lockObject, TRAPS) {
464 464 assert_lock_strong(SystemDictionary_lock);
465 465
466 466 bool calledholdinglock
467 467 = ObjectSynchronizer::current_thread_holds_lock((JavaThread*)THREAD, lockObject);
468 468 assert(calledholdinglock,"must hold lock for notify");
469 469 assert((!(lockObject() == _system_loader_lock_obj) && !is_parallelCapable(lockObject)), "unexpected double_lock_wait");
470 470 ObjectSynchronizer::notifyall(lockObject, THREAD);
471 471 intptr_t recursions = ObjectSynchronizer::complete_exit(lockObject, THREAD);
472 472 SystemDictionary_lock->wait();
473 473 SystemDictionary_lock->unlock();
474 474 ObjectSynchronizer::reenter(lockObject, recursions, THREAD);
475 475 SystemDictionary_lock->lock();
476 476 }
477 477
478 478 // If the class in is in the placeholder table, class loading is in progress
479 479 // For cases where the application changes threads to load classes, it
480 480 // is critical to ClassCircularity detection that we try loading
481 481 // the superclass on the same thread internally, so we do parallel
482 482 // super class loading here.
483 483 // This also is critical in cases where the original thread gets stalled
484 484 // even in non-circularity situations.
485 485 // Note: only one thread can define the class, but multiple can resolve
486 486 // Note: must call resolve_super_or_fail even if null super -
487 487 // to force placeholder entry creation for this class for circularity detection
488 488 // Caller must check for pending exception
489 489 // Returns non-null klassOop if other thread has completed load
490 490 // and we are done,
491 491 // If return null klassOop and no pending exception, the caller must load the class
492 492 instanceKlassHandle SystemDictionary::handle_parallel_super_load(
493 493 Symbol* name, Symbol* superclassname, Handle class_loader,
494 494 Handle protection_domain, Handle lockObject, TRAPS) {
495 495
496 496 instanceKlassHandle nh = instanceKlassHandle(); // null Handle
497 497 unsigned int d_hash = dictionary()->compute_hash(name, class_loader);
498 498 int d_index = dictionary()->hash_to_index(d_hash);
499 499 unsigned int p_hash = placeholders()->compute_hash(name, class_loader);
500 500 int p_index = placeholders()->hash_to_index(p_hash);
501 501
502 502 // superk is not used, resolve_super called for circularity check only
503 503 // This code is reached in two situations. One if this thread
504 504 // is loading the same class twice (e.g. ClassCircularity, or
505 505 // java.lang.instrument).
506 506 // The second is if another thread started the resolve_super first
507 507 // and has not yet finished.
508 508 // In both cases the original caller will clean up the placeholder
509 509 // entry on error.
510 510 klassOop superk = SystemDictionary::resolve_super_or_fail(name,
511 511 superclassname,
512 512 class_loader,
513 513 protection_domain,
514 514 true,
515 515 CHECK_(nh));
516 516 // We don't redefine the class, so we just need to clean up if there
517 517 // was not an error (don't want to modify any system dictionary
518 518 // data structures).
519 519 {
520 520 MutexLocker mu(SystemDictionary_lock, THREAD);
521 521 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
522 522 SystemDictionary_lock->notify_all();
523 523 }
524 524
525 525 // parallelCapable class loaders do NOT wait for parallel superclass loads to complete
526 526 // Serial class loaders and bootstrap classloader do wait for superclass loads
527 527 if (!class_loader.is_null() && is_parallelCapable(class_loader)) {
528 528 MutexLocker mu(SystemDictionary_lock, THREAD);
529 529 // Check if classloading completed while we were loading superclass or waiting
530 530 klassOop check = find_class(d_index, d_hash, name, class_loader);
531 531 if (check != NULL) {
532 532 // Klass is already loaded, so just return it
533 533 return(instanceKlassHandle(THREAD, check));
534 534 } else {
535 535 return nh;
536 536 }
537 537 }
538 538
539 539 // must loop to both handle other placeholder updates
540 540 // and spurious notifications
541 541 bool super_load_in_progress = true;
542 542 PlaceholderEntry* placeholder;
543 543 while (super_load_in_progress) {
544 544 MutexLocker mu(SystemDictionary_lock, THREAD);
545 545 // Check if classloading completed while we were loading superclass or waiting
546 546 klassOop check = find_class(d_index, d_hash, name, class_loader);
547 547 if (check != NULL) {
548 548 // Klass is already loaded, so just return it
549 549 return(instanceKlassHandle(THREAD, check));
550 550 } else {
551 551 placeholder = placeholders()->get_entry(p_index, p_hash, name, class_loader);
552 552 if (placeholder && placeholder->super_load_in_progress() ){
553 553 // Before UnsyncloadClass:
554 554 // We only get here if the application has released the
555 555 // classloader lock when another thread was in the middle of loading a
556 556 // superclass/superinterface for this class, and now
557 557 // this thread is also trying to load this class.
558 558 // To minimize surprises, the first thread that started to
559 559 // load a class should be the one to complete the loading
560 560 // with the classfile it initially expected.
561 561 // This logic has the current thread wait once it has done
562 562 // all the superclass/superinterface loading it can, until
563 563 // the original thread completes the class loading or fails
564 564 // If it completes we will use the resulting instanceKlass
565 565 // which we will find below in the systemDictionary.
566 566 // We also get here for parallel bootstrap classloader
567 567 if (class_loader.is_null()) {
568 568 SystemDictionary_lock->wait();
569 569 } else {
570 570 double_lock_wait(lockObject, THREAD);
571 571 }
572 572 } else {
573 573 // If not in SD and not in PH, other thread's load must have failed
574 574 super_load_in_progress = false;
575 575 }
576 576 }
577 577 }
578 578 return (nh);
579 579 }
580 580
581 581
582 582 klassOop SystemDictionary::resolve_instance_class_or_null(Symbol* name, Handle class_loader, Handle protection_domain, TRAPS) {
583 583 assert(name != NULL && !FieldType::is_array(name) &&
584 584 !FieldType::is_obj(name), "invalid class name");
585 585
586 586 // UseNewReflection
587 587 // Fix for 4474172; see evaluation for more details
588 588 class_loader = Handle(THREAD, java_lang_ClassLoader::non_reflection_class_loader(class_loader()));
589 589
590 590 // Do lookup to see if class already exist and the protection domain
591 591 // has the right access
592 592 unsigned int d_hash = dictionary()->compute_hash(name, class_loader);
593 593 int d_index = dictionary()->hash_to_index(d_hash);
594 594 klassOop probe = dictionary()->find(d_index, d_hash, name, class_loader,
595 595 protection_domain, THREAD);
596 596 if (probe != NULL) return probe;
597 597
598 598
599 599 // Non-bootstrap class loaders will call out to class loader and
600 600 // define via jvm/jni_DefineClass which will acquire the
601 601 // class loader object lock to protect against multiple threads
602 602 // defining the class in parallel by accident.
603 603 // This lock must be acquired here so the waiter will find
604 604 // any successful result in the SystemDictionary and not attempt
605 605 // the define
606 606 // ParallelCapable Classloaders and the bootstrap classloader,
607 607 // or all classloaders with UnsyncloadClass do not acquire lock here
608 608 bool DoObjectLock = true;
609 609 if (is_parallelCapable(class_loader)) {
610 610 DoObjectLock = false;
611 611 }
612 612
613 613 unsigned int p_hash = placeholders()->compute_hash(name, class_loader);
614 614 int p_index = placeholders()->hash_to_index(p_hash);
615 615
616 616 // Class is not in SystemDictionary so we have to do loading.
617 617 // Make sure we are synchronized on the class loader before we proceed
618 618 Handle lockObject = compute_loader_lock_object(class_loader, THREAD);
619 619 check_loader_lock_contention(lockObject, THREAD);
620 620 ObjectLocker ol(lockObject, THREAD, DoObjectLock);
621 621
622 622 // Check again (after locking) if class already exist in SystemDictionary
623 623 bool class_has_been_loaded = false;
624 624 bool super_load_in_progress = false;
625 625 bool havesupername = false;
626 626 instanceKlassHandle k;
627 627 PlaceholderEntry* placeholder;
628 628 Symbol* superclassname = NULL;
629 629
630 630 {
631 631 MutexLocker mu(SystemDictionary_lock, THREAD);
632 632 klassOop check = find_class(d_index, d_hash, name, class_loader);
633 633 if (check != NULL) {
634 634 // Klass is already loaded, so just return it
635 635 class_has_been_loaded = true;
636 636 k = instanceKlassHandle(THREAD, check);
637 637 } else {
638 638 placeholder = placeholders()->get_entry(p_index, p_hash, name, class_loader);
639 639 if (placeholder && placeholder->super_load_in_progress()) {
640 640 super_load_in_progress = true;
641 641 if (placeholder->havesupername() == true) {
642 642 superclassname = placeholder->supername();
643 643 havesupername = true;
644 644 }
645 645 }
646 646 }
647 647 }
648 648
649 649 // If the class in is in the placeholder table, class loading is in progress
650 650 if (super_load_in_progress && havesupername==true) {
651 651 k = SystemDictionary::handle_parallel_super_load(name, superclassname,
652 652 class_loader, protection_domain, lockObject, THREAD);
653 653 if (HAS_PENDING_EXCEPTION) {
654 654 return NULL;
655 655 }
656 656 if (!k.is_null()) {
657 657 class_has_been_loaded = true;
658 658 }
659 659 }
660 660
661 661 if (!class_has_been_loaded) {
662 662
663 663 // add placeholder entry to record loading instance class
664 664 // Five cases:
665 665 // All cases need to prevent modifying bootclasssearchpath
666 666 // in parallel with a classload of same classname
667 667 // Redefineclasses uses existence of the placeholder for the duration
668 668 // of the class load to prevent concurrent redefinition of not completely
669 669 // defined classes.
670 670 // case 1. traditional classloaders that rely on the classloader object lock
671 671 // - no other need for LOAD_INSTANCE
672 672 // case 2. traditional classloaders that break the classloader object lock
673 673 // as a deadlock workaround. Detection of this case requires that
674 674 // this check is done while holding the classloader object lock,
675 675 // and that lock is still held when calling classloader's loadClass.
676 676 // For these classloaders, we ensure that the first requestor
677 677 // completes the load and other requestors wait for completion.
678 678 // case 3. UnsyncloadClass - don't use objectLocker
679 679 // With this flag, we allow parallel classloading of a
680 680 // class/classloader pair
681 681 // case4. Bootstrap classloader - don't own objectLocker
682 682 // This classloader supports parallelism at the classloader level,
683 683 // but only allows a single load of a class/classloader pair.
684 684 // No performance benefit and no deadlock issues.
685 685 // case 5. parallelCapable user level classloaders - without objectLocker
686 686 // Allow parallel classloading of a class/classloader pair
687 687 bool throw_circularity_error = false;
688 688 {
689 689 MutexLocker mu(SystemDictionary_lock, THREAD);
690 690 if (class_loader.is_null() || !is_parallelCapable(class_loader)) {
691 691 PlaceholderEntry* oldprobe = placeholders()->get_entry(p_index, p_hash, name, class_loader);
692 692 if (oldprobe) {
693 693 // only need check_seen_thread once, not on each loop
694 694 // 6341374 java/lang/Instrument with -Xcomp
695 695 if (oldprobe->check_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE)) {
696 696 throw_circularity_error = true;
697 697 } else {
698 698 // case 1: traditional: should never see load_in_progress.
699 699 while (!class_has_been_loaded && oldprobe && oldprobe->instance_load_in_progress()) {
700 700
701 701 // case 4: bootstrap classloader: prevent futile classloading,
702 702 // wait on first requestor
703 703 if (class_loader.is_null()) {
704 704 SystemDictionary_lock->wait();
705 705 } else {
706 706 // case 2: traditional with broken classloader lock. wait on first
707 707 // requestor.
708 708 double_lock_wait(lockObject, THREAD);
709 709 }
710 710 // Check if classloading completed while we were waiting
711 711 klassOop check = find_class(d_index, d_hash, name, class_loader);
712 712 if (check != NULL) {
713 713 // Klass is already loaded, so just return it
714 714 k = instanceKlassHandle(THREAD, check);
715 715 class_has_been_loaded = true;
716 716 }
717 717 // check if other thread failed to load and cleaned up
718 718 oldprobe = placeholders()->get_entry(p_index, p_hash, name, class_loader);
719 719 }
720 720 }
721 721 }
722 722 }
723 723 // All cases: add LOAD_INSTANCE
724 724 // case 3: UnsyncloadClass || case 5: parallelCapable: allow competing threads to try
725 725 // LOAD_INSTANCE in parallel
726 726 // add placeholder entry even if error - callers will remove on error
727 727 if (!throw_circularity_error && !class_has_been_loaded) {
728 728 PlaceholderEntry* newprobe = placeholders()->find_and_add(p_index, p_hash, name, class_loader, PlaceholderTable::LOAD_INSTANCE, NULL, THREAD);
729 729 // For class loaders that do not acquire the classloader object lock,
730 730 // if they did not catch another thread holding LOAD_INSTANCE,
731 731 // need a check analogous to the acquire ObjectLocker/find_class
732 732 // i.e. now that we hold the LOAD_INSTANCE token on loading this class/CL
733 733 // one final check if the load has already completed
734 734 // class loaders holding the ObjectLock shouldn't find the class here
735 735 klassOop check = find_class(d_index, d_hash, name, class_loader);
736 736 if (check != NULL) {
737 737 // Klass is already loaded, so just return it
738 738 k = instanceKlassHandle(THREAD, check);
739 739 class_has_been_loaded = true;
740 740 newprobe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE);
741 741 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
742 742 SystemDictionary_lock->notify_all();
743 743 }
744 744 }
745 745 }
746 746 // must throw error outside of owning lock
747 747 if (throw_circularity_error) {
748 748 ResourceMark rm(THREAD);
749 749 THROW_MSG_0(vmSymbols::java_lang_ClassCircularityError(), name->as_C_string());
750 750 }
751 751
752 752 if (!class_has_been_loaded) {
753 753
754 754 // Do actual loading
755 755 k = load_instance_class(name, class_loader, THREAD);
756 756
757 757 // For UnsyncloadClass only
758 758 // If they got a linkageError, check if a parallel class load succeeded.
759 759 // If it did, then for bytecode resolution the specification requires
760 760 // that we return the same result we did for the other thread, i.e. the
761 761 // successfully loaded instanceKlass
762 762 // Should not get here for classloaders that support parallelism
763 763 // with the new cleaner mechanism, even with AllowParallelDefineClass
764 764 // Bootstrap goes through here to allow for an extra guarantee check
765 765 if (UnsyncloadClass || (class_loader.is_null())) {
766 766 if (k.is_null() && HAS_PENDING_EXCEPTION
767 767 && PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
768 768 MutexLocker mu(SystemDictionary_lock, THREAD);
769 769 klassOop check = find_class(d_index, d_hash, name, class_loader);
770 770 if (check != NULL) {
771 771 // Klass is already loaded, so just use it
772 772 k = instanceKlassHandle(THREAD, check);
773 773 CLEAR_PENDING_EXCEPTION;
774 774 guarantee((!class_loader.is_null()), "dup definition for bootstrap loader?");
775 775 }
776 776 }
777 777 }
778 778
779 779 // clean up placeholder entries for success or error
780 780 // This cleans up LOAD_INSTANCE entries
781 781 // It also cleans up LOAD_SUPER entries on errors from
782 782 // calling load_instance_class
783 783 {
784 784 MutexLocker mu(SystemDictionary_lock, THREAD);
785 785 PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, name, class_loader);
786 786 if (probe != NULL) {
787 787 probe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE);
788 788 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
789 789 SystemDictionary_lock->notify_all();
790 790 }
791 791 }
792 792
793 793 // If everything was OK (no exceptions, no null return value), and
794 794 // class_loader is NOT the defining loader, do a little more bookkeeping.
795 795 if (!HAS_PENDING_EXCEPTION && !k.is_null() &&
796 796 k->class_loader() != class_loader()) {
797 797
798 798 check_constraints(d_index, d_hash, k, class_loader, false, THREAD);
799 799
800 800 // Need to check for a PENDING_EXCEPTION again; check_constraints
801 801 // can throw and doesn't use the CHECK macro.
802 802 if (!HAS_PENDING_EXCEPTION) {
803 803 { // Grabbing the Compile_lock prevents systemDictionary updates
804 804 // during compilations.
805 805 MutexLocker mu(Compile_lock, THREAD);
806 806 update_dictionary(d_index, d_hash, p_index, p_hash,
807 807 k, class_loader, THREAD);
808 808 }
809 809 if (JvmtiExport::should_post_class_load()) {
810 810 Thread *thread = THREAD;
811 811 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
812 812 JvmtiExport::post_class_load((JavaThread *) thread, k());
813 813 }
814 814 }
815 815 }
816 816 if (HAS_PENDING_EXCEPTION || k.is_null()) {
817 817 // On error, clean up placeholders
818 818 {
819 819 MutexLocker mu(SystemDictionary_lock, THREAD);
820 820 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
821 821 SystemDictionary_lock->notify_all();
822 822 }
823 823 return NULL;
824 824 }
825 825 }
826 826 }
827 827
828 828 #ifdef ASSERT
829 829 {
830 830 Handle loader (THREAD, k->class_loader());
831 831 MutexLocker mu(SystemDictionary_lock, THREAD);
832 832 oop kk = find_class(name, loader);
833 833 assert(kk == k(), "should be present in dictionary");
834 834 }
835 835 #endif
836 836
837 837 // return if the protection domain in NULL
838 838 if (protection_domain() == NULL) return k();
839 839
840 840 // Check the protection domain has the right access
841 841 {
842 842 MutexLocker mu(SystemDictionary_lock, THREAD);
843 843 // Note that we have an entry, and entries can be deleted only during GC,
844 844 // so we cannot allow GC to occur while we're holding this entry.
845 845 // We're using a No_Safepoint_Verifier to catch any place where we
846 846 // might potentially do a GC at all.
847 847 // SystemDictionary::do_unloading() asserts that classes are only
848 848 // unloaded at a safepoint.
849 849 No_Safepoint_Verifier nosafepoint;
850 850 if (dictionary()->is_valid_protection_domain(d_index, d_hash, name,
851 851 class_loader,
852 852 protection_domain)) {
853 853 return k();
854 854 }
855 855 }
856 856
857 857 // Verify protection domain. If it fails an exception is thrown
858 858 validate_protection_domain(k, class_loader, protection_domain, CHECK_(klassOop(NULL)));
859 859
860 860 return k();
861 861 }
862 862
863 863
864 864 // This routine does not lock the system dictionary.
865 865 //
866 866 // Since readers don't hold a lock, we must make sure that system
867 867 // dictionary entries are only removed at a safepoint (when only one
868 868 // thread is running), and are added to in a safe way (all links must
869 869 // be updated in an MT-safe manner).
870 870 //
871 871 // Callers should be aware that an entry could be added just after
872 872 // _dictionary->bucket(index) is read here, so the caller will not see
873 873 // the new entry.
874 874
875 875 klassOop SystemDictionary::find(Symbol* class_name,
876 876 Handle class_loader,
877 877 Handle protection_domain,
878 878 TRAPS) {
879 879
880 880 // UseNewReflection
881 881 // The result of this call should be consistent with the result
882 882 // of the call to resolve_instance_class_or_null().
883 883 // See evaluation 6790209 and 4474172 for more details.
884 884 class_loader = Handle(THREAD, java_lang_ClassLoader::non_reflection_class_loader(class_loader()));
885 885
886 886 unsigned int d_hash = dictionary()->compute_hash(class_name, class_loader);
887 887 int d_index = dictionary()->hash_to_index(d_hash);
888 888
889 889 {
890 890 // Note that we have an entry, and entries can be deleted only during GC,
891 891 // so we cannot allow GC to occur while we're holding this entry.
892 892 // We're using a No_Safepoint_Verifier to catch any place where we
893 893 // might potentially do a GC at all.
894 894 // SystemDictionary::do_unloading() asserts that classes are only
895 895 // unloaded at a safepoint.
896 896 No_Safepoint_Verifier nosafepoint;
897 897 return dictionary()->find(d_index, d_hash, class_name, class_loader,
898 898 protection_domain, THREAD);
899 899 }
900 900 }
901 901
902 902
903 903 // Look for a loaded instance or array klass by name. Do not do any loading.
904 904 // return NULL in case of error.
905 905 klassOop SystemDictionary::find_instance_or_array_klass(Symbol* class_name,
906 906 Handle class_loader,
907 907 Handle protection_domain,
908 908 TRAPS) {
909 909 klassOop k = NULL;
910 910 assert(class_name != NULL, "class name must be non NULL");
911 911
912 912 // Try to get one of the well-known klasses.
913 913 if (LinkWellKnownClasses) {
914 914 k = find_well_known_klass(class_name);
915 915 if (k != NULL) {
916 916 return k;
917 917 }
918 918 }
919 919
920 920 if (FieldType::is_array(class_name)) {
921 921 // The name refers to an array. Parse the name.
922 922 // dimension and object_key in FieldArrayInfo are assigned as a
923 923 // side-effect of this call
924 924 FieldArrayInfo fd;
925 925 BasicType t = FieldType::get_array_info(class_name, fd, CHECK_(NULL));
926 926 if (t != T_OBJECT) {
927 927 k = Universe::typeArrayKlassObj(t);
928 928 } else {
929 929 k = SystemDictionary::find(fd.object_key(), class_loader, protection_domain, THREAD);
930 930 }
931 931 if (k != NULL) {
932 932 k = Klass::cast(k)->array_klass_or_null(fd.dimension());
933 933 }
934 934 } else {
935 935 k = find(class_name, class_loader, protection_domain, THREAD);
936 936 }
937 937 return k;
938 938 }
939 939
940 940 // Quick range check for names of well-known classes:
941 941 static Symbol* wk_klass_name_limits[2] = {NULL, NULL};
942 942
943 943 #ifndef PRODUCT
944 944 static int find_wkk_calls, find_wkk_probes, find_wkk_wins;
945 945 // counts for "hello world": 3983, 1616, 1075
946 946 // => 60% hit after limit guard, 25% total win rate
947 947 #endif
948 948
949 949 klassOop SystemDictionary::find_well_known_klass(Symbol* class_name) {
950 950 // A bounds-check on class_name will quickly get a negative result.
951 951 NOT_PRODUCT(find_wkk_calls++);
952 952 if (class_name >= wk_klass_name_limits[0] &&
953 953 class_name <= wk_klass_name_limits[1]) {
954 954 NOT_PRODUCT(find_wkk_probes++);
955 955 vmSymbols::SID sid = vmSymbols::find_sid(class_name);
956 956 if (sid != vmSymbols::NO_SID) {
957 957 klassOop k = NULL;
958 958 switch (sid) {
959 959 #define WK_KLASS_CASE(name, symbol, ignore_option) \
960 960 case vmSymbols::VM_SYMBOL_ENUM_NAME(symbol): \
961 961 k = WK_KLASS(name); break;
962 962 WK_KLASSES_DO(WK_KLASS_CASE)
963 963 #undef WK_KLASS_CASE
964 964 }
965 965 NOT_PRODUCT(if (k != NULL) find_wkk_wins++);
966 966 return k;
967 967 }
968 968 }
969 969 return NULL;
970 970 }
971 971
972 972 // Note: this method is much like resolve_from_stream, but
973 973 // updates no supplemental data structures.
974 974 // TODO consolidate the two methods with a helper routine?
975 975 klassOop SystemDictionary::parse_stream(Symbol* class_name,
976 976 Handle class_loader,
977 977 Handle protection_domain,
978 978 ClassFileStream* st,
979 979 KlassHandle host_klass,
980 980 GrowableArray<Handle>* cp_patches,
981 981 TRAPS) {
982 982 TempNewSymbol parsed_name = NULL;
983 983
984 984 // Parse the stream. Note that we do this even though this klass might
985 985 // already be present in the SystemDictionary, otherwise we would not
986 986 // throw potential ClassFormatErrors.
987 987 //
988 988 // Note: "name" is updated.
989 989 // Further note: a placeholder will be added for this class when
990 990 // super classes are loaded (resolve_super_or_fail). We expect this
991 991 // to be called for all classes but java.lang.Object; and we preload
992 992 // java.lang.Object through resolve_or_fail, not this path.
993 993
994 994 instanceKlassHandle k = ClassFileParser(st).parseClassFile(class_name,
995 995 class_loader,
996 996 protection_domain,
997 997 host_klass,
998 998 cp_patches,
999 999 parsed_name,
1000 1000 true,
1001 1001 THREAD);
1002 1002
1003 1003 // We don't redefine the class, so we just need to clean up whether there
1004 1004 // was an error or not (don't want to modify any system dictionary
1005 1005 // data structures).
1006 1006 // Parsed name could be null if we threw an error before we got far
1007 1007 // enough along to parse it -- in that case, there is nothing to clean up.
1008 1008 if (parsed_name != NULL) {
1009 1009 unsigned int p_hash = placeholders()->compute_hash(parsed_name,
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1010 1010 class_loader);
1011 1011 int p_index = placeholders()->hash_to_index(p_hash);
1012 1012 {
1013 1013 MutexLocker mu(SystemDictionary_lock, THREAD);
1014 1014 placeholders()->find_and_remove(p_index, p_hash, parsed_name, class_loader, THREAD);
1015 1015 SystemDictionary_lock->notify_all();
1016 1016 }
1017 1017 }
1018 1018
1019 1019 if (host_klass.not_null() && k.not_null()) {
1020 - assert(AnonymousClasses, "");
1020 + assert(EnableInvokeDynamic, "");
1021 1021 // If it's anonymous, initialize it now, since nobody else will.
1022 1022 k->set_host_klass(host_klass());
1023 1023
1024 1024 {
1025 1025 MutexLocker mu_r(Compile_lock, THREAD);
1026 1026
1027 1027 // Add to class hierarchy, initialize vtables, and do possible
1028 1028 // deoptimizations.
1029 1029 add_to_hierarchy(k, CHECK_NULL); // No exception, but can block
1030 1030
1031 1031 // But, do not add to system dictionary.
1032 1032 }
1033 1033
1034 1034 k->eager_initialize(THREAD);
1035 1035
1036 1036 // notify jvmti
1037 1037 if (JvmtiExport::should_post_class_load()) {
1038 1038 assert(THREAD->is_Java_thread(), "thread->is_Java_thread()");
1039 1039 JvmtiExport::post_class_load((JavaThread *) THREAD, k());
1040 1040 }
1041 1041 }
1042 1042
1043 1043 return k();
1044 1044 }
1045 1045
1046 1046 // Add a klass to the system from a stream (called by jni_DefineClass and
1047 1047 // JVM_DefineClass).
1048 1048 // Note: class_name can be NULL. In that case we do not know the name of
1049 1049 // the class until we have parsed the stream.
1050 1050
1051 1051 klassOop SystemDictionary::resolve_from_stream(Symbol* class_name,
1052 1052 Handle class_loader,
1053 1053 Handle protection_domain,
1054 1054 ClassFileStream* st,
1055 1055 bool verify,
1056 1056 TRAPS) {
1057 1057
1058 1058 // Classloaders that support parallelism, e.g. bootstrap classloader,
1059 1059 // or all classloaders with UnsyncloadClass do not acquire lock here
1060 1060 bool DoObjectLock = true;
1061 1061 if (is_parallelCapable(class_loader)) {
1062 1062 DoObjectLock = false;
1063 1063 }
1064 1064
1065 1065 // Make sure we are synchronized on the class loader before we proceed
1066 1066 Handle lockObject = compute_loader_lock_object(class_loader, THREAD);
1067 1067 check_loader_lock_contention(lockObject, THREAD);
1068 1068 ObjectLocker ol(lockObject, THREAD, DoObjectLock);
1069 1069
1070 1070 TempNewSymbol parsed_name = NULL;
1071 1071
1072 1072 // Parse the stream. Note that we do this even though this klass might
1073 1073 // already be present in the SystemDictionary, otherwise we would not
1074 1074 // throw potential ClassFormatErrors.
1075 1075 //
1076 1076 // Note: "name" is updated.
1077 1077 // Further note: a placeholder will be added for this class when
1078 1078 // super classes are loaded (resolve_super_or_fail). We expect this
1079 1079 // to be called for all classes but java.lang.Object; and we preload
1080 1080 // java.lang.Object through resolve_or_fail, not this path.
1081 1081
1082 1082 instanceKlassHandle k = ClassFileParser(st).parseClassFile(class_name,
1083 1083 class_loader,
1084 1084 protection_domain,
1085 1085 parsed_name,
1086 1086 verify,
1087 1087 THREAD);
1088 1088
1089 1089 const char* pkg = "java/";
1090 1090 if (!HAS_PENDING_EXCEPTION &&
1091 1091 !class_loader.is_null() &&
1092 1092 parsed_name != NULL &&
1093 1093 !strncmp((const char*)parsed_name->bytes(), pkg, strlen(pkg))) {
1094 1094 // It is illegal to define classes in the "java." package from
1095 1095 // JVM_DefineClass or jni_DefineClass unless you're the bootclassloader
1096 1096 ResourceMark rm(THREAD);
1097 1097 char* name = parsed_name->as_C_string();
1098 1098 char* index = strrchr(name, '/');
1099 1099 *index = '\0'; // chop to just the package name
1100 1100 while ((index = strchr(name, '/')) != NULL) {
1101 1101 *index = '.'; // replace '/' with '.' in package name
1102 1102 }
1103 1103 const char* fmt = "Prohibited package name: %s";
1104 1104 size_t len = strlen(fmt) + strlen(name);
1105 1105 char* message = NEW_RESOURCE_ARRAY(char, len);
1106 1106 jio_snprintf(message, len, fmt, name);
1107 1107 Exceptions::_throw_msg(THREAD_AND_LOCATION,
1108 1108 vmSymbols::java_lang_SecurityException(), message);
1109 1109 }
1110 1110
1111 1111 if (!HAS_PENDING_EXCEPTION) {
1112 1112 assert(parsed_name != NULL, "Sanity");
1113 1113 assert(class_name == NULL || class_name == parsed_name, "name mismatch");
1114 1114 // Verification prevents us from creating names with dots in them, this
1115 1115 // asserts that that's the case.
1116 1116 assert(is_internal_format(parsed_name),
1117 1117 "external class name format used internally");
1118 1118
1119 1119 // Add class just loaded
1120 1120 // If a class loader supports parallel classloading handle parallel define requests
1121 1121 // find_or_define_instance_class may return a different instanceKlass
1122 1122 if (is_parallelCapable(class_loader)) {
1123 1123 k = find_or_define_instance_class(class_name, class_loader, k, THREAD);
1124 1124 } else {
1125 1125 define_instance_class(k, THREAD);
1126 1126 }
1127 1127 }
1128 1128
1129 1129 // If parsing the class file or define_instance_class failed, we
1130 1130 // need to remove the placeholder added on our behalf. But we
1131 1131 // must make sure parsed_name is valid first (it won't be if we had
1132 1132 // a format error before the class was parsed far enough to
1133 1133 // find the name).
1134 1134 if (HAS_PENDING_EXCEPTION && parsed_name != NULL) {
1135 1135 unsigned int p_hash = placeholders()->compute_hash(parsed_name,
1136 1136 class_loader);
1137 1137 int p_index = placeholders()->hash_to_index(p_hash);
1138 1138 {
1139 1139 MutexLocker mu(SystemDictionary_lock, THREAD);
1140 1140 placeholders()->find_and_remove(p_index, p_hash, parsed_name, class_loader, THREAD);
1141 1141 SystemDictionary_lock->notify_all();
1142 1142 }
1143 1143 return NULL;
1144 1144 }
1145 1145
1146 1146 // Make sure that we didn't leave a place holder in the
1147 1147 // SystemDictionary; this is only done on success
1148 1148 debug_only( {
1149 1149 if (!HAS_PENDING_EXCEPTION) {
1150 1150 assert(parsed_name != NULL, "parsed_name is still null?");
1151 1151 Symbol* h_name = k->name();
1152 1152 Handle h_loader (THREAD, k->class_loader());
1153 1153
1154 1154 MutexLocker mu(SystemDictionary_lock, THREAD);
1155 1155
1156 1156 klassOop check = find_class(parsed_name, class_loader);
1157 1157 assert(check == k(), "should be present in the dictionary");
1158 1158
1159 1159 klassOop check2 = find_class(h_name, h_loader);
1160 1160 assert(check == check2, "name inconsistancy in SystemDictionary");
1161 1161 }
1162 1162 } );
1163 1163
1164 1164 return k();
1165 1165 }
1166 1166
1167 1167
1168 1168 void SystemDictionary::set_shared_dictionary(HashtableBucket* t, int length,
1169 1169 int number_of_entries) {
1170 1170 assert(length == _nof_buckets * sizeof(HashtableBucket),
1171 1171 "bad shared dictionary size.");
1172 1172 _shared_dictionary = new Dictionary(_nof_buckets, t, number_of_entries);
1173 1173 }
1174 1174
1175 1175
1176 1176 // If there is a shared dictionary, then find the entry for the
1177 1177 // given shared system class, if any.
1178 1178
1179 1179 klassOop SystemDictionary::find_shared_class(Symbol* class_name) {
1180 1180 if (shared_dictionary() != NULL) {
1181 1181 unsigned int d_hash = dictionary()->compute_hash(class_name, Handle());
1182 1182 int d_index = dictionary()->hash_to_index(d_hash);
1183 1183 return shared_dictionary()->find_shared_class(d_index, d_hash, class_name);
1184 1184 } else {
1185 1185 return NULL;
1186 1186 }
1187 1187 }
1188 1188
1189 1189
1190 1190 // Load a class from the shared spaces (found through the shared system
1191 1191 // dictionary). Force the superclass and all interfaces to be loaded.
1192 1192 // Update the class definition to include sibling classes and no
1193 1193 // subclasses (yet). [Classes in the shared space are not part of the
1194 1194 // object hierarchy until loaded.]
1195 1195
1196 1196 instanceKlassHandle SystemDictionary::load_shared_class(
1197 1197 Symbol* class_name, Handle class_loader, TRAPS) {
1198 1198 instanceKlassHandle ik (THREAD, find_shared_class(class_name));
1199 1199 return load_shared_class(ik, class_loader, THREAD);
1200 1200 }
1201 1201
1202 1202 // Note well! Changes to this method may affect oop access order
1203 1203 // in the shared archive. Please take care to not make changes that
1204 1204 // adversely affect cold start time by changing the oop access order
1205 1205 // that is specified in dump.cpp MarkAndMoveOrderedReadOnly and
1206 1206 // MarkAndMoveOrderedReadWrite closures.
1207 1207 instanceKlassHandle SystemDictionary::load_shared_class(
1208 1208 instanceKlassHandle ik, Handle class_loader, TRAPS) {
1209 1209 assert(class_loader.is_null(), "non-null classloader for shared class?");
1210 1210 if (ik.not_null()) {
1211 1211 instanceKlassHandle nh = instanceKlassHandle(); // null Handle
1212 1212 Symbol* class_name = ik->name();
1213 1213
1214 1214 // Found the class, now load the superclass and interfaces. If they
1215 1215 // are shared, add them to the main system dictionary and reset
1216 1216 // their hierarchy references (supers, subs, and interfaces).
1217 1217
1218 1218 if (ik->super() != NULL) {
1219 1219 Symbol* cn = ik->super()->klass_part()->name();
1220 1220 resolve_super_or_fail(class_name, cn,
1221 1221 class_loader, Handle(), true, CHECK_(nh));
1222 1222 }
1223 1223
1224 1224 objArrayHandle interfaces (THREAD, ik->local_interfaces());
1225 1225 int num_interfaces = interfaces->length();
1226 1226 for (int index = 0; index < num_interfaces; index++) {
1227 1227 klassOop k = klassOop(interfaces->obj_at(index));
1228 1228
1229 1229 // Note: can not use instanceKlass::cast here because
1230 1230 // interfaces' instanceKlass's C++ vtbls haven't been
1231 1231 // reinitialized yet (they will be once the interface classes
1232 1232 // are loaded)
1233 1233 Symbol* name = k->klass_part()->name();
1234 1234 resolve_super_or_fail(class_name, name, class_loader, Handle(), false, CHECK_(nh));
1235 1235 }
1236 1236
1237 1237 // Adjust methods to recover missing data. They need addresses for
1238 1238 // interpreter entry points and their default native method address
1239 1239 // must be reset.
1240 1240
1241 1241 // Updating methods must be done under a lock so multiple
1242 1242 // threads don't update these in parallel
1243 1243 // Shared classes are all currently loaded by the bootstrap
1244 1244 // classloader, so this will never cause a deadlock on
1245 1245 // a custom class loader lock.
1246 1246
1247 1247 {
1248 1248 Handle lockObject = compute_loader_lock_object(class_loader, THREAD);
1249 1249 check_loader_lock_contention(lockObject, THREAD);
1250 1250 ObjectLocker ol(lockObject, THREAD, true);
1251 1251
1252 1252 objArrayHandle methods (THREAD, ik->methods());
1253 1253 int num_methods = methods->length();
1254 1254 for (int index2 = 0; index2 < num_methods; ++index2) {
1255 1255 methodHandle m(THREAD, methodOop(methods->obj_at(index2)));
1256 1256 m()->link_method(m, CHECK_(nh));
1257 1257 }
1258 1258 }
1259 1259
1260 1260 if (TraceClassLoading) {
1261 1261 ResourceMark rm;
1262 1262 tty->print("[Loaded %s", ik->external_name());
1263 1263 tty->print(" from shared objects file");
1264 1264 tty->print_cr("]");
1265 1265 }
1266 1266 // notify a class loaded from shared object
1267 1267 ClassLoadingService::notify_class_loaded(instanceKlass::cast(ik()),
1268 1268 true /* shared class */);
1269 1269 }
1270 1270 return ik;
1271 1271 }
1272 1272
1273 1273 #ifdef KERNEL
1274 1274 // Some classes on the bootstrap class path haven't been installed on the
1275 1275 // system yet. Call the DownloadManager method to make them appear in the
1276 1276 // bootstrap class path and try again to load the named class.
1277 1277 // Note that with delegation class loaders all classes in another loader will
1278 1278 // first try to call this so it'd better be fast!!
1279 1279 static instanceKlassHandle download_and_retry_class_load(
1280 1280 Symbol* class_name,
1281 1281 TRAPS) {
1282 1282
1283 1283 klassOop dlm = SystemDictionary::sun_jkernel_DownloadManager_klass();
1284 1284 instanceKlassHandle nk;
1285 1285
1286 1286 // If download manager class isn't loaded just return.
1287 1287 if (dlm == NULL) return nk;
1288 1288
1289 1289 { HandleMark hm(THREAD);
1290 1290 ResourceMark rm(THREAD);
1291 1291 Handle s = java_lang_String::create_from_symbol(class_name, CHECK_(nk));
1292 1292 Handle class_string = java_lang_String::externalize_classname(s, CHECK_(nk));
1293 1293
1294 1294 // return value
1295 1295 JavaValue result(T_OBJECT);
1296 1296
1297 1297 // Call the DownloadManager. We assume that it has a lock because
1298 1298 // multiple classes could be not found and downloaded at the same time.
1299 1299 // class sun.misc.DownloadManager;
1300 1300 // public static String getBootClassPathEntryForClass(String className);
1301 1301 JavaCalls::call_static(&result,
1302 1302 KlassHandle(THREAD, dlm),
1303 1303 vmSymbols::getBootClassPathEntryForClass_name(),
1304 1304 vmSymbols::string_string_signature(),
1305 1305 class_string,
1306 1306 CHECK_(nk));
1307 1307
1308 1308 // Get result.string and add to bootclasspath
1309 1309 assert(result.get_type() == T_OBJECT, "just checking");
1310 1310 oop obj = (oop) result.get_jobject();
1311 1311 if (obj == NULL) { return nk; }
1312 1312
1313 1313 Handle h_obj(THREAD, obj);
1314 1314 char* new_class_name = java_lang_String::as_platform_dependent_str(h_obj,
1315 1315 CHECK_(nk));
1316 1316
1317 1317 // lock the loader
1318 1318 // we use this lock because JVMTI does.
1319 1319 Handle loader_lock(THREAD, SystemDictionary::system_loader_lock());
1320 1320
1321 1321 ObjectLocker ol(loader_lock, THREAD);
1322 1322 // add the file to the bootclasspath
1323 1323 ClassLoader::update_class_path_entry_list(new_class_name, true);
1324 1324 } // end HandleMark
1325 1325
1326 1326 if (TraceClassLoading) {
1327 1327 ClassLoader::print_bootclasspath();
1328 1328 }
1329 1329 return ClassLoader::load_classfile(class_name, CHECK_(nk));
1330 1330 }
1331 1331 #endif // KERNEL
1332 1332
1333 1333
1334 1334 instanceKlassHandle SystemDictionary::load_instance_class(Symbol* class_name, Handle class_loader, TRAPS) {
1335 1335 instanceKlassHandle nh = instanceKlassHandle(); // null Handle
1336 1336 if (class_loader.is_null()) {
1337 1337
1338 1338 // Search the shared system dictionary for classes preloaded into the
1339 1339 // shared spaces.
1340 1340 instanceKlassHandle k;
1341 1341 {
1342 1342 PerfTraceTime vmtimer(ClassLoader::perf_shared_classload_time());
1343 1343 k = load_shared_class(class_name, class_loader, THREAD);
1344 1344 }
1345 1345
1346 1346 if (k.is_null()) {
1347 1347 // Use VM class loader
1348 1348 PerfTraceTime vmtimer(ClassLoader::perf_sys_classload_time());
1349 1349 k = ClassLoader::load_classfile(class_name, CHECK_(nh));
1350 1350 }
1351 1351
1352 1352 #ifdef KERNEL
1353 1353 // If the VM class loader has failed to load the class, call the
1354 1354 // DownloadManager class to make it magically appear on the classpath
1355 1355 // and try again. This is only configured with the Kernel VM.
1356 1356 if (k.is_null()) {
1357 1357 k = download_and_retry_class_load(class_name, CHECK_(nh));
1358 1358 }
1359 1359 #endif // KERNEL
1360 1360
1361 1361 // find_or_define_instance_class may return a different instanceKlass
1362 1362 if (!k.is_null()) {
1363 1363 k = find_or_define_instance_class(class_name, class_loader, k, CHECK_(nh));
1364 1364 }
1365 1365 return k;
1366 1366 } else {
1367 1367 // Use user specified class loader to load class. Call loadClass operation on class_loader.
1368 1368 ResourceMark rm(THREAD);
1369 1369
1370 1370 assert(THREAD->is_Java_thread(), "must be a JavaThread");
1371 1371 JavaThread* jt = (JavaThread*) THREAD;
1372 1372
1373 1373 PerfClassTraceTime vmtimer(ClassLoader::perf_app_classload_time(),
1374 1374 ClassLoader::perf_app_classload_selftime(),
1375 1375 ClassLoader::perf_app_classload_count(),
1376 1376 jt->get_thread_stat()->perf_recursion_counts_addr(),
1377 1377 jt->get_thread_stat()->perf_timers_addr(),
1378 1378 PerfClassTraceTime::CLASS_LOAD);
1379 1379
1380 1380 Handle s = java_lang_String::create_from_symbol(class_name, CHECK_(nh));
1381 1381 // Translate to external class name format, i.e., convert '/' chars to '.'
1382 1382 Handle string = java_lang_String::externalize_classname(s, CHECK_(nh));
1383 1383
1384 1384 JavaValue result(T_OBJECT);
1385 1385
1386 1386 KlassHandle spec_klass (THREAD, SystemDictionary::ClassLoader_klass());
1387 1387
1388 1388 // Call public unsynchronized loadClass(String) directly for all class loaders
1389 1389 // for parallelCapable class loaders. JDK >=7, loadClass(String, boolean) will
1390 1390 // acquire a class-name based lock rather than the class loader object lock.
1391 1391 // JDK < 7 already acquire the class loader lock in loadClass(String, boolean),
1392 1392 // so the call to loadClassInternal() was not required.
1393 1393 //
1394 1394 // UnsyncloadClass flag means both call loadClass(String) and do
1395 1395 // not acquire the class loader lock even for class loaders that are
1396 1396 // not parallelCapable. This was a risky transitional
1397 1397 // flag for diagnostic purposes only. It is risky to call
1398 1398 // custom class loaders without synchronization.
1399 1399 // WARNING If a custom class loader does NOT synchronizer findClass, or callers of
1400 1400 // findClass, the UnsyncloadClass flag risks unexpected timing bugs in the field.
1401 1401 // Do NOT assume this will be supported in future releases.
1402 1402 //
1403 1403 // Added MustCallLoadClassInternal in case we discover in the field
1404 1404 // a customer that counts on this call
1405 1405 if (MustCallLoadClassInternal && has_loadClassInternal()) {
1406 1406 JavaCalls::call_special(&result,
1407 1407 class_loader,
1408 1408 spec_klass,
1409 1409 vmSymbols::loadClassInternal_name(),
1410 1410 vmSymbols::string_class_signature(),
1411 1411 string,
1412 1412 CHECK_(nh));
1413 1413 } else {
1414 1414 JavaCalls::call_virtual(&result,
1415 1415 class_loader,
1416 1416 spec_klass,
1417 1417 vmSymbols::loadClass_name(),
1418 1418 vmSymbols::string_class_signature(),
1419 1419 string,
1420 1420 CHECK_(nh));
1421 1421 }
1422 1422
1423 1423 assert(result.get_type() == T_OBJECT, "just checking");
1424 1424 oop obj = (oop) result.get_jobject();
1425 1425
1426 1426 // Primitive classes return null since forName() can not be
1427 1427 // used to obtain any of the Class objects representing primitives or void
1428 1428 if ((obj != NULL) && !(java_lang_Class::is_primitive(obj))) {
1429 1429 instanceKlassHandle k =
1430 1430 instanceKlassHandle(THREAD, java_lang_Class::as_klassOop(obj));
1431 1431 // For user defined Java class loaders, check that the name returned is
1432 1432 // the same as that requested. This check is done for the bootstrap
1433 1433 // loader when parsing the class file.
1434 1434 if (class_name == k->name()) {
1435 1435 return k;
1436 1436 }
1437 1437 }
1438 1438 // Class is not found or has the wrong name, return NULL
1439 1439 return nh;
1440 1440 }
1441 1441 }
1442 1442
1443 1443 void SystemDictionary::define_instance_class(instanceKlassHandle k, TRAPS) {
1444 1444
1445 1445 Handle class_loader_h(THREAD, k->class_loader());
1446 1446
1447 1447 // for bootstrap and other parallel classloaders don't acquire lock,
1448 1448 // use placeholder token
1449 1449 // If a parallelCapable class loader calls define_instance_class instead of
1450 1450 // find_or_define_instance_class to get here, we have a timing
1451 1451 // hole with systemDictionary updates and check_constraints
1452 1452 if (!class_loader_h.is_null() && !is_parallelCapable(class_loader_h)) {
1453 1453 assert(ObjectSynchronizer::current_thread_holds_lock((JavaThread*)THREAD,
1454 1454 compute_loader_lock_object(class_loader_h, THREAD)),
1455 1455 "define called without lock");
1456 1456 }
1457 1457
1458 1458 // Check class-loading constraints. Throw exception if violation is detected.
1459 1459 // Grabs and releases SystemDictionary_lock
1460 1460 // The check_constraints/find_class call and update_dictionary sequence
1461 1461 // must be "atomic" for a specific class/classloader pair so we never
1462 1462 // define two different instanceKlasses for that class/classloader pair.
1463 1463 // Existing classloaders will call define_instance_class with the
1464 1464 // classloader lock held
1465 1465 // Parallel classloaders will call find_or_define_instance_class
1466 1466 // which will require a token to perform the define class
1467 1467 Symbol* name_h = k->name();
1468 1468 unsigned int d_hash = dictionary()->compute_hash(name_h, class_loader_h);
1469 1469 int d_index = dictionary()->hash_to_index(d_hash);
1470 1470 check_constraints(d_index, d_hash, k, class_loader_h, true, CHECK);
1471 1471
1472 1472 // Register class just loaded with class loader (placed in Vector)
1473 1473 // Note we do this before updating the dictionary, as this can
1474 1474 // fail with an OutOfMemoryError (if it does, we will *not* put this
1475 1475 // class in the dictionary and will not update the class hierarchy).
1476 1476 if (k->class_loader() != NULL) {
1477 1477 methodHandle m(THREAD, Universe::loader_addClass_method());
1478 1478 JavaValue result(T_VOID);
1479 1479 JavaCallArguments args(class_loader_h);
1480 1480 args.push_oop(Handle(THREAD, k->java_mirror()));
1481 1481 JavaCalls::call(&result, m, &args, CHECK);
1482 1482 }
1483 1483
1484 1484 // Add the new class. We need recompile lock during update of CHA.
1485 1485 {
1486 1486 unsigned int p_hash = placeholders()->compute_hash(name_h, class_loader_h);
1487 1487 int p_index = placeholders()->hash_to_index(p_hash);
1488 1488
1489 1489 MutexLocker mu_r(Compile_lock, THREAD);
1490 1490
1491 1491 // Add to class hierarchy, initialize vtables, and do possible
1492 1492 // deoptimizations.
1493 1493 add_to_hierarchy(k, CHECK); // No exception, but can block
1494 1494
1495 1495 // Add to systemDictionary - so other classes can see it.
1496 1496 // Grabs and releases SystemDictionary_lock
1497 1497 update_dictionary(d_index, d_hash, p_index, p_hash,
1498 1498 k, class_loader_h, THREAD);
1499 1499 }
1500 1500 k->eager_initialize(THREAD);
1501 1501
1502 1502 // notify jvmti
1503 1503 if (JvmtiExport::should_post_class_load()) {
1504 1504 assert(THREAD->is_Java_thread(), "thread->is_Java_thread()");
1505 1505 JvmtiExport::post_class_load((JavaThread *) THREAD, k());
1506 1506
1507 1507 }
1508 1508 }
1509 1509
1510 1510 // Support parallel classloading
1511 1511 // All parallel class loaders, including bootstrap classloader
1512 1512 // lock a placeholder entry for this class/class_loader pair
1513 1513 // to allow parallel defines of different classes for this class loader
1514 1514 // With AllowParallelDefine flag==true, in case they do not synchronize around
1515 1515 // FindLoadedClass/DefineClass, calls, we check for parallel
1516 1516 // loading for them, wait if a defineClass is in progress
1517 1517 // and return the initial requestor's results
1518 1518 // This flag does not apply to the bootstrap classloader.
1519 1519 // With AllowParallelDefine flag==false, call through to define_instance_class
1520 1520 // which will throw LinkageError: duplicate class definition.
1521 1521 // False is the requested default.
1522 1522 // For better performance, the class loaders should synchronize
1523 1523 // findClass(), i.e. FindLoadedClass/DefineClassIfAbsent or they
1524 1524 // potentially waste time reading and parsing the bytestream.
1525 1525 // Note: VM callers should ensure consistency of k/class_name,class_loader
1526 1526 instanceKlassHandle SystemDictionary::find_or_define_instance_class(Symbol* class_name, Handle class_loader, instanceKlassHandle k, TRAPS) {
1527 1527
1528 1528 instanceKlassHandle nh = instanceKlassHandle(); // null Handle
1529 1529 Symbol* name_h = k->name(); // passed in class_name may be null
1530 1530
1531 1531 unsigned int d_hash = dictionary()->compute_hash(name_h, class_loader);
1532 1532 int d_index = dictionary()->hash_to_index(d_hash);
1533 1533
1534 1534 // Hold SD lock around find_class and placeholder creation for DEFINE_CLASS
1535 1535 unsigned int p_hash = placeholders()->compute_hash(name_h, class_loader);
1536 1536 int p_index = placeholders()->hash_to_index(p_hash);
1537 1537 PlaceholderEntry* probe;
1538 1538
1539 1539 {
1540 1540 MutexLocker mu(SystemDictionary_lock, THREAD);
1541 1541 // First check if class already defined
1542 1542 if (UnsyncloadClass || (is_parallelDefine(class_loader))) {
1543 1543 klassOop check = find_class(d_index, d_hash, name_h, class_loader);
1544 1544 if (check != NULL) {
1545 1545 return(instanceKlassHandle(THREAD, check));
1546 1546 }
1547 1547 }
1548 1548
1549 1549 // Acquire define token for this class/classloader
1550 1550 probe = placeholders()->find_and_add(p_index, p_hash, name_h, class_loader, PlaceholderTable::DEFINE_CLASS, NULL, THREAD);
1551 1551 // Wait if another thread defining in parallel
1552 1552 // All threads wait - even those that will throw duplicate class: otherwise
1553 1553 // caller is surprised by LinkageError: duplicate, but findLoadedClass fails
1554 1554 // if other thread has not finished updating dictionary
1555 1555 while (probe->definer() != NULL) {
1556 1556 SystemDictionary_lock->wait();
1557 1557 }
1558 1558 // Only special cases allow parallel defines and can use other thread's results
1559 1559 // Other cases fall through, and may run into duplicate defines
1560 1560 // caught by finding an entry in the SystemDictionary
1561 1561 if ((UnsyncloadClass || is_parallelDefine(class_loader)) && (probe->instanceKlass() != NULL)) {
1562 1562 probe->remove_seen_thread(THREAD, PlaceholderTable::DEFINE_CLASS);
1563 1563 placeholders()->find_and_remove(p_index, p_hash, name_h, class_loader, THREAD);
1564 1564 SystemDictionary_lock->notify_all();
1565 1565 #ifdef ASSERT
1566 1566 klassOop check = find_class(d_index, d_hash, name_h, class_loader);
1567 1567 assert(check != NULL, "definer missed recording success");
1568 1568 #endif
1569 1569 return(instanceKlassHandle(THREAD, probe->instanceKlass()));
1570 1570 } else {
1571 1571 // This thread will define the class (even if earlier thread tried and had an error)
1572 1572 probe->set_definer(THREAD);
1573 1573 }
1574 1574 }
1575 1575
1576 1576 define_instance_class(k, THREAD);
1577 1577
1578 1578 Handle linkage_exception = Handle(); // null handle
1579 1579
1580 1580 // definer must notify any waiting threads
1581 1581 {
1582 1582 MutexLocker mu(SystemDictionary_lock, THREAD);
1583 1583 PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, name_h, class_loader);
1584 1584 assert(probe != NULL, "DEFINE_CLASS placeholder lost?");
1585 1585 if (probe != NULL) {
1586 1586 if (HAS_PENDING_EXCEPTION) {
1587 1587 linkage_exception = Handle(THREAD,PENDING_EXCEPTION);
1588 1588 CLEAR_PENDING_EXCEPTION;
1589 1589 } else {
1590 1590 probe->set_instanceKlass(k());
1591 1591 }
1592 1592 probe->set_definer(NULL);
1593 1593 probe->remove_seen_thread(THREAD, PlaceholderTable::DEFINE_CLASS);
1594 1594 placeholders()->find_and_remove(p_index, p_hash, name_h, class_loader, THREAD);
1595 1595 SystemDictionary_lock->notify_all();
1596 1596 }
1597 1597 }
1598 1598
1599 1599 // Can't throw exception while holding lock due to rank ordering
1600 1600 if (linkage_exception() != NULL) {
1601 1601 THROW_OOP_(linkage_exception(), nh); // throws exception and returns
1602 1602 }
1603 1603
1604 1604 return k;
1605 1605 }
1606 1606 Handle SystemDictionary::compute_loader_lock_object(Handle class_loader, TRAPS) {
1607 1607 // If class_loader is NULL we synchronize on _system_loader_lock_obj
1608 1608 if (class_loader.is_null()) {
1609 1609 return Handle(THREAD, _system_loader_lock_obj);
1610 1610 } else {
1611 1611 return class_loader;
1612 1612 }
1613 1613 }
1614 1614
1615 1615 // This method is added to check how often we have to wait to grab loader
1616 1616 // lock. The results are being recorded in the performance counters defined in
1617 1617 // ClassLoader::_sync_systemLoaderLockContentionRate and
1618 1618 // ClassLoader::_sync_nonSystemLoaderLockConteionRate.
1619 1619 void SystemDictionary::check_loader_lock_contention(Handle loader_lock, TRAPS) {
1620 1620 if (!UsePerfData) {
1621 1621 return;
1622 1622 }
1623 1623
1624 1624 assert(!loader_lock.is_null(), "NULL lock object");
1625 1625
1626 1626 if (ObjectSynchronizer::query_lock_ownership((JavaThread*)THREAD, loader_lock)
1627 1627 == ObjectSynchronizer::owner_other) {
1628 1628 // contention will likely happen, so increment the corresponding
1629 1629 // contention counter.
1630 1630 if (loader_lock() == _system_loader_lock_obj) {
1631 1631 ClassLoader::sync_systemLoaderLockContentionRate()->inc();
1632 1632 } else {
1633 1633 ClassLoader::sync_nonSystemLoaderLockContentionRate()->inc();
1634 1634 }
1635 1635 }
1636 1636 }
1637 1637
1638 1638 // ----------------------------------------------------------------------------
1639 1639 // Lookup
1640 1640
1641 1641 klassOop SystemDictionary::find_class(int index, unsigned int hash,
1642 1642 Symbol* class_name,
1643 1643 Handle class_loader) {
1644 1644 assert_locked_or_safepoint(SystemDictionary_lock);
1645 1645 assert (index == dictionary()->index_for(class_name, class_loader),
1646 1646 "incorrect index?");
1647 1647
1648 1648 klassOop k = dictionary()->find_class(index, hash, class_name, class_loader);
1649 1649 return k;
1650 1650 }
1651 1651
1652 1652
1653 1653 // Basic find on classes in the midst of being loaded
1654 1654 Symbol* SystemDictionary::find_placeholder(Symbol* class_name,
1655 1655 Handle class_loader) {
1656 1656 assert_locked_or_safepoint(SystemDictionary_lock);
1657 1657 unsigned int p_hash = placeholders()->compute_hash(class_name, class_loader);
1658 1658 int p_index = placeholders()->hash_to_index(p_hash);
1659 1659 return placeholders()->find_entry(p_index, p_hash, class_name, class_loader);
1660 1660 }
1661 1661
1662 1662
1663 1663 // Used for assertions and verification only
1664 1664 klassOop SystemDictionary::find_class(Symbol* class_name, Handle class_loader) {
1665 1665 #ifndef ASSERT
1666 1666 guarantee(VerifyBeforeGC ||
1667 1667 VerifyDuringGC ||
1668 1668 VerifyBeforeExit ||
1669 1669 VerifyAfterGC, "too expensive");
1670 1670 #endif
1671 1671 assert_locked_or_safepoint(SystemDictionary_lock);
1672 1672
1673 1673 // First look in the loaded class array
1674 1674 unsigned int d_hash = dictionary()->compute_hash(class_name, class_loader);
1675 1675 int d_index = dictionary()->hash_to_index(d_hash);
1676 1676 return find_class(d_index, d_hash, class_name, class_loader);
1677 1677 }
1678 1678
1679 1679
1680 1680 // Get the next class in the diictionary.
1681 1681 klassOop SystemDictionary::try_get_next_class() {
1682 1682 return dictionary()->try_get_next_class();
1683 1683 }
1684 1684
1685 1685
1686 1686 // ----------------------------------------------------------------------------
1687 1687 // Update hierachy. This is done before the new klass has been added to the SystemDictionary. The Recompile_lock
1688 1688 // is held, to ensure that the compiler is not using the class hierachy, and that deoptimization will kick in
1689 1689 // before a new class is used.
1690 1690
1691 1691 void SystemDictionary::add_to_hierarchy(instanceKlassHandle k, TRAPS) {
1692 1692 assert(k.not_null(), "just checking");
1693 1693 assert_locked_or_safepoint(Compile_lock);
1694 1694
1695 1695 // Link into hierachy. Make sure the vtables are initialized before linking into
1696 1696 k->append_to_sibling_list(); // add to superklass/sibling list
1697 1697 k->process_interfaces(THREAD); // handle all "implements" declarations
1698 1698 k->set_init_state(instanceKlass::loaded);
1699 1699 // Now flush all code that depended on old class hierarchy.
1700 1700 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
1701 1701 // Also, first reinitialize vtable because it may have gotten out of synch
1702 1702 // while the new class wasn't connected to the class hierarchy.
1703 1703 Universe::flush_dependents_on(k);
1704 1704 }
1705 1705
1706 1706
1707 1707 // ----------------------------------------------------------------------------
1708 1708 // GC support
1709 1709
1710 1710 // Following roots during mark-sweep is separated in two phases.
1711 1711 //
1712 1712 // The first phase follows preloaded classes and all other system
1713 1713 // classes, since these will never get unloaded anyway.
1714 1714 //
1715 1715 // The second phase removes (unloads) unreachable classes from the
1716 1716 // system dictionary and follows the remaining classes' contents.
1717 1717
1718 1718 void SystemDictionary::always_strong_oops_do(OopClosure* blk) {
1719 1719 // Follow preloaded classes/mirrors and system loader object
1720 1720 blk->do_oop(&_java_system_loader);
1721 1721 preloaded_oops_do(blk);
1722 1722 always_strong_classes_do(blk);
1723 1723 }
1724 1724
1725 1725
1726 1726 void SystemDictionary::always_strong_classes_do(OopClosure* blk) {
1727 1727 // Follow all system classes and temporary placeholders in dictionary
1728 1728 dictionary()->always_strong_classes_do(blk);
1729 1729
1730 1730 // Placeholders. These are *always* strong roots, as they
1731 1731 // represent classes we're actively loading.
1732 1732 placeholders_do(blk);
1733 1733
1734 1734 // Visit extra methods
1735 1735 invoke_method_table()->oops_do(blk);
1736 1736 }
1737 1737
1738 1738
1739 1739 void SystemDictionary::placeholders_do(OopClosure* blk) {
1740 1740 placeholders()->oops_do(blk);
1741 1741 }
1742 1742
1743 1743
1744 1744 bool SystemDictionary::do_unloading(BoolObjectClosure* is_alive) {
1745 1745 bool result = dictionary()->do_unloading(is_alive);
1746 1746 constraints()->purge_loader_constraints(is_alive);
1747 1747 resolution_errors()->purge_resolution_errors(is_alive);
1748 1748 return result;
1749 1749 }
1750 1750
1751 1751
1752 1752 // The mirrors are scanned by shared_oops_do() which is
1753 1753 // not called by oops_do(). In order to process oops in
1754 1754 // a necessary order, shared_oops_do() is call by
1755 1755 // Universe::oops_do().
1756 1756 void SystemDictionary::oops_do(OopClosure* f) {
1757 1757 // Adjust preloaded classes and system loader object
1758 1758 f->do_oop(&_java_system_loader);
1759 1759 preloaded_oops_do(f);
1760 1760
1761 1761 lazily_loaded_oops_do(f);
1762 1762
1763 1763 // Adjust dictionary
1764 1764 dictionary()->oops_do(f);
1765 1765
1766 1766 // Visit extra methods
1767 1767 invoke_method_table()->oops_do(f);
1768 1768
1769 1769 // Partially loaded classes
1770 1770 placeholders()->oops_do(f);
1771 1771
1772 1772 // Adjust constraint table
1773 1773 constraints()->oops_do(f);
1774 1774
1775 1775 // Adjust resolution error table
1776 1776 resolution_errors()->oops_do(f);
1777 1777 }
1778 1778
1779 1779
1780 1780 void SystemDictionary::preloaded_oops_do(OopClosure* f) {
1781 1781 for (int k = (int)FIRST_WKID; k < (int)WKID_LIMIT; k++) {
1782 1782 f->do_oop((oop*) &_well_known_klasses[k]);
1783 1783 }
1784 1784
1785 1785 {
1786 1786 for (int i = 0; i < T_VOID+1; i++) {
1787 1787 if (_box_klasses[i] != NULL) {
1788 1788 assert(i >= T_BOOLEAN, "checking");
1789 1789 f->do_oop((oop*) &_box_klasses[i]);
1790 1790 }
1791 1791 }
1792 1792 }
1793 1793
1794 1794 // The basic type mirrors would have already been processed in
1795 1795 // Universe::oops_do(), via a call to shared_oops_do(), so should
1796 1796 // not be processed again.
1797 1797
1798 1798 f->do_oop((oop*) &_system_loader_lock_obj);
1799 1799 FilteredFieldsMap::klasses_oops_do(f);
1800 1800 }
1801 1801
1802 1802 void SystemDictionary::lazily_loaded_oops_do(OopClosure* f) {
1803 1803 f->do_oop((oop*) &_abstract_ownable_synchronizer_klass);
1804 1804 }
1805 1805
1806 1806 // Just the classes from defining class loaders
1807 1807 // Don't iterate over placeholders
1808 1808 void SystemDictionary::classes_do(void f(klassOop)) {
1809 1809 dictionary()->classes_do(f);
1810 1810 }
1811 1811
1812 1812 // Added for initialize_itable_for_klass
1813 1813 // Just the classes from defining class loaders
1814 1814 // Don't iterate over placeholders
1815 1815 void SystemDictionary::classes_do(void f(klassOop, TRAPS), TRAPS) {
1816 1816 dictionary()->classes_do(f, CHECK);
1817 1817 }
1818 1818
1819 1819 // All classes, and their class loaders
1820 1820 // Don't iterate over placeholders
1821 1821 void SystemDictionary::classes_do(void f(klassOop, oop)) {
1822 1822 dictionary()->classes_do(f);
1823 1823 }
1824 1824
1825 1825 // All classes, and their class loaders
1826 1826 // (added for helpers that use HandleMarks and ResourceMarks)
1827 1827 // Don't iterate over placeholders
1828 1828 void SystemDictionary::classes_do(void f(klassOop, oop, TRAPS), TRAPS) {
1829 1829 dictionary()->classes_do(f, CHECK);
1830 1830 }
1831 1831
1832 1832 void SystemDictionary::placeholders_do(void f(Symbol*, oop)) {
1833 1833 placeholders()->entries_do(f);
1834 1834 }
1835 1835
1836 1836 void SystemDictionary::methods_do(void f(methodOop)) {
1837 1837 dictionary()->methods_do(f);
1838 1838 invoke_method_table()->methods_do(f);
1839 1839 }
1840 1840
1841 1841 // ----------------------------------------------------------------------------
1842 1842 // Lazily load klasses
1843 1843
1844 1844 void SystemDictionary::load_abstract_ownable_synchronizer_klass(TRAPS) {
1845 1845 assert(JDK_Version::is_gte_jdk16x_version(), "Must be JDK 1.6 or later");
1846 1846
1847 1847 // if multiple threads calling this function, only one thread will load
1848 1848 // the class. The other threads will find the loaded version once the
1849 1849 // class is loaded.
1850 1850 klassOop aos = _abstract_ownable_synchronizer_klass;
1851 1851 if (aos == NULL) {
1852 1852 klassOop k = resolve_or_fail(vmSymbols::java_util_concurrent_locks_AbstractOwnableSynchronizer(), true, CHECK);
1853 1853 // Force a fence to prevent any read before the write completes
1854 1854 OrderAccess::fence();
1855 1855 _abstract_ownable_synchronizer_klass = k;
1856 1856 }
1857 1857 }
1858 1858
1859 1859 // ----------------------------------------------------------------------------
1860 1860 // Initialization
1861 1861
1862 1862 void SystemDictionary::initialize(TRAPS) {
1863 1863 // Allocate arrays
1864 1864 assert(dictionary() == NULL,
1865 1865 "SystemDictionary should only be initialized once");
1866 1866 _dictionary = new Dictionary(_nof_buckets);
1867 1867 _placeholders = new PlaceholderTable(_nof_buckets);
1868 1868 _number_of_modifications = 0;
1869 1869 _loader_constraints = new LoaderConstraintTable(_loader_constraint_size);
1870 1870 _resolution_errors = new ResolutionErrorTable(_resolution_error_size);
1871 1871 _invoke_method_table = new SymbolPropertyTable(_invoke_method_size);
1872 1872
1873 1873 // Allocate private object used as system class loader lock
1874 1874 _system_loader_lock_obj = oopFactory::new_system_objArray(0, CHECK);
1875 1875 // Initialize basic classes
1876 1876 initialize_preloaded_classes(CHECK);
1877 1877 }
1878 1878
1879 1879 // Compact table of directions on the initialization of klasses:
1880 1880 static const short wk_init_info[] = {
1881 1881 #define WK_KLASS_INIT_INFO(name, symbol, option) \
1882 1882 ( ((int)vmSymbols::VM_SYMBOL_ENUM_NAME(symbol) \
1883 1883 << SystemDictionary::CEIL_LG_OPTION_LIMIT) \
1884 1884 | (int)SystemDictionary::option ),
1885 1885 WK_KLASSES_DO(WK_KLASS_INIT_INFO)
1886 1886 #undef WK_KLASS_INIT_INFO
1887 1887 0
1888 1888 };
1889 1889
1890 1890 Symbol* SystemDictionary::find_backup_symbol(Symbol* symbol,
1891 1891 const char* from_prefix,
1892 1892 const char* to_prefix) {
1893 1893 assert(AllowTransitionalJSR292, ""); // delete this subroutine
1894 1894 Symbol* backup_symbol = NULL;
1895 1895 size_t from_len = strlen(from_prefix);
1896 1896 if (strncmp((const char*) symbol->base(), from_prefix, from_len) != 0)
1897 1897 return NULL;
1898 1898 char buf[100];
1899 1899 size_t to_len = strlen(to_prefix);
1900 1900 size_t tail_len = symbol->utf8_length() - from_len;
1901 1901 size_t new_len = to_len + tail_len;
1902 1902 guarantee(new_len < sizeof(buf), "buf too small");
1903 1903 memcpy(buf, to_prefix, to_len);
1904 1904 memcpy(buf + to_len, symbol->base() + from_len, tail_len);
1905 1905 buf[new_len] = '\0';
1906 1906 vmSymbols::SID backup_sid = vmSymbols::find_sid(buf);
1907 1907 if (backup_sid != vmSymbols::NO_SID) {
1908 1908 backup_symbol = vmSymbols::symbol_at(backup_sid);
1909 1909 }
1910 1910 return backup_symbol;
1911 1911 }
1912 1912
1913 1913 Symbol* SystemDictionary::find_backup_class_name(Symbol* symbol) {
1914 1914 assert(AllowTransitionalJSR292, ""); // delete this subroutine
1915 1915 if (symbol == NULL) return NULL;
1916 1916 Symbol* backup_symbol = find_backup_symbol(symbol, "java/lang/invoke/", "java/dyn/"); // AllowTransitionalJSR292 ONLY
1917 1917 if (backup_symbol == NULL)
1918 1918 backup_symbol = find_backup_symbol(symbol, "java/dyn/", "sun/dyn/"); // AllowTransitionalJSR292 ONLY
1919 1919 return backup_symbol;
1920 1920 }
1921 1921
1922 1922 Symbol* SystemDictionary::find_backup_signature(Symbol* symbol) {
1923 1923 assert(AllowTransitionalJSR292, ""); // delete this subroutine
1924 1924 if (symbol == NULL) return NULL;
1925 1925 return find_backup_symbol(symbol, "Ljava/lang/invoke/", "Ljava/dyn/");
1926 1926 }
1927 1927
1928 1928 bool SystemDictionary::initialize_wk_klass(WKID id, int init_opt, TRAPS) {
1929 1929 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
1930 1930 int info = wk_init_info[id - FIRST_WKID];
1931 1931 int sid = (info >> CEIL_LG_OPTION_LIMIT);
1932 1932 Symbol* symbol = vmSymbols::symbol_at((vmSymbols::SID)sid);
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1933 1933 klassOop* klassp = &_well_known_klasses[id];
1934 1934 bool pre_load = (init_opt < SystemDictionary::Opt);
1935 1935 bool try_load = true;
1936 1936 if (init_opt == SystemDictionary::Opt_Kernel) {
1937 1937 #ifndef KERNEL
1938 1938 try_load = false;
1939 1939 #endif //KERNEL
1940 1940 }
1941 1941 Symbol* backup_symbol = NULL; // symbol to try if the current symbol fails
1942 1942 if (init_opt == SystemDictionary::Pre_JSR292) {
1943 - if (!EnableMethodHandles) try_load = false; // do not bother to load such classes
1943 + if (!EnableInvokeDynamic) try_load = false; // do not bother to load such classes
1944 1944 if (AllowTransitionalJSR292) {
1945 1945 backup_symbol = find_backup_class_name(symbol);
1946 1946 if (try_load && PreferTransitionalJSR292) {
1947 1947 while (backup_symbol != NULL) {
1948 1948 (*klassp) = resolve_or_null(backup_symbol, CHECK_0); // try backup early
1949 1949 if (TraceMethodHandles) {
1950 1950 ResourceMark rm;
1951 1951 tty->print_cr("MethodHandles: try backup first for %s => %s (%s)",
1952 1952 symbol->as_C_string(), backup_symbol->as_C_string(),
1953 1953 ((*klassp) == NULL) ? "no such class" : "backup load succeeded");
1954 1954 }
1955 1955 if ((*klassp) != NULL) return true;
1956 1956 backup_symbol = find_backup_class_name(backup_symbol); // find next backup
1957 1957 }
1958 1958 }
1959 1959 }
1960 1960 }
1961 1961 if ((*klassp) != NULL) return true;
1962 1962 if (!try_load) return false;
1963 1963 while (symbol != NULL) {
1964 1964 bool must_load = (pre_load && (backup_symbol == NULL));
1965 1965 if (must_load) {
1966 1966 (*klassp) = resolve_or_fail(symbol, true, CHECK_0); // load required class
1967 1967 } else {
1968 1968 (*klassp) = resolve_or_null(symbol, CHECK_0); // load optional klass
1969 1969 }
1970 1970 if ((*klassp) != NULL) return true;
1971 1971 // Go around again. Example of long backup sequence:
1972 1972 // java.lang.invoke.MemberName, java.dyn.MemberName, sun.dyn.MemberName, ONLY if AllowTransitionalJSR292
1973 1973 if (TraceMethodHandles && (backup_symbol != NULL)) {
1974 1974 ResourceMark rm;
1975 1975 tty->print_cr("MethodHandles: backup for %s => %s",
1976 1976 symbol->as_C_string(), backup_symbol->as_C_string());
1977 1977 }
1978 1978 symbol = backup_symbol;
1979 1979 if (AllowTransitionalJSR292)
1980 1980 backup_symbol = find_backup_class_name(symbol);
1981 1981 }
1982 1982 return false;
1983 1983 }
1984 1984
1985 1985 void SystemDictionary::initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS) {
1986 1986 assert((int)start_id <= (int)limit_id, "IDs are out of order!");
1987 1987 for (int id = (int)start_id; id < (int)limit_id; id++) {
1988 1988 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
1989 1989 int info = wk_init_info[id - FIRST_WKID];
1990 1990 int sid = (info >> CEIL_LG_OPTION_LIMIT);
1991 1991 int opt = (info & right_n_bits(CEIL_LG_OPTION_LIMIT));
1992 1992
1993 1993 initialize_wk_klass((WKID)id, opt, CHECK);
1994 1994
1995 1995 // Update limits, so find_well_known_klass can be very fast:
1996 1996 Symbol* s = vmSymbols::symbol_at((vmSymbols::SID)sid);
1997 1997 if (wk_klass_name_limits[1] == NULL) {
1998 1998 wk_klass_name_limits[0] = wk_klass_name_limits[1] = s;
1999 1999 } else if (wk_klass_name_limits[1] < s) {
2000 2000 wk_klass_name_limits[1] = s;
2001 2001 } else if (wk_klass_name_limits[0] > s) {
2002 2002 wk_klass_name_limits[0] = s;
2003 2003 }
2004 2004 }
2005 2005
2006 2006 // move the starting value forward to the limit:
2007 2007 start_id = limit_id;
2008 2008 }
2009 2009
2010 2010
2011 2011 void SystemDictionary::initialize_preloaded_classes(TRAPS) {
2012 2012 assert(WK_KLASS(Object_klass) == NULL, "preloaded classes should only be initialized once");
2013 2013 // Preload commonly used klasses
2014 2014 WKID scan = FIRST_WKID;
2015 2015 // first do Object, String, Class
2016 2016 initialize_wk_klasses_through(WK_KLASS_ENUM_NAME(Class_klass), scan, CHECK);
2017 2017
2018 2018 debug_only(instanceKlass::verify_class_klass_nonstatic_oop_maps(WK_KLASS(Class_klass)));
2019 2019
2020 2020 // Fixup mirrors for classes loaded before java.lang.Class.
2021 2021 // These calls iterate over the objects currently in the perm gen
2022 2022 // so calling them at this point is matters (not before when there
2023 2023 // are fewer objects and not later after there are more objects
2024 2024 // in the perm gen.
2025 2025 Universe::initialize_basic_type_mirrors(CHECK);
2026 2026 Universe::fixup_mirrors(CHECK);
2027 2027
2028 2028 // do a bunch more:
2029 2029 initialize_wk_klasses_through(WK_KLASS_ENUM_NAME(Reference_klass), scan, CHECK);
2030 2030
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2031 2031 // Preload ref klasses and set reference types
2032 2032 instanceKlass::cast(WK_KLASS(Reference_klass))->set_reference_type(REF_OTHER);
2033 2033 instanceRefKlass::update_nonstatic_oop_maps(WK_KLASS(Reference_klass));
2034 2034
2035 2035 initialize_wk_klasses_through(WK_KLASS_ENUM_NAME(PhantomReference_klass), scan, CHECK);
2036 2036 instanceKlass::cast(WK_KLASS(SoftReference_klass))->set_reference_type(REF_SOFT);
2037 2037 instanceKlass::cast(WK_KLASS(WeakReference_klass))->set_reference_type(REF_WEAK);
2038 2038 instanceKlass::cast(WK_KLASS(FinalReference_klass))->set_reference_type(REF_FINAL);
2039 2039 instanceKlass::cast(WK_KLASS(PhantomReference_klass))->set_reference_type(REF_PHANTOM);
2040 2040
2041 - WKID meth_group_start = WK_KLASS_ENUM_NAME(MethodHandle_klass);
2042 - WKID meth_group_end = WK_KLASS_ENUM_NAME(WrongMethodTypeException_klass);
2043 - initialize_wk_klasses_until(meth_group_start, scan, CHECK);
2044 - if (EnableMethodHandles) {
2045 - initialize_wk_klasses_through(meth_group_end, scan, CHECK);
2046 - }
2047 - if (_well_known_klasses[meth_group_start] == NULL) {
2048 - // Skip the rest of the method handle classes, if MethodHandle is not loaded.
2049 - scan = WKID(meth_group_end+1);
2050 - }
2051 - WKID indy_group_start = WK_KLASS_ENUM_NAME(Linkage_klass);
2052 - WKID indy_group_end = WK_KLASS_ENUM_NAME(CallSite_klass);
2053 - initialize_wk_klasses_until(indy_group_start, scan, CHECK);
2041 + // JSR 292 classes
2042 + WKID jsr292_group_start = WK_KLASS_ENUM_NAME(MethodHandle_klass);
2043 + WKID jsr292_group_end = WK_KLASS_ENUM_NAME(CallSite_klass);
2044 + initialize_wk_klasses_until(jsr292_group_start, scan, CHECK);
2054 2045 if (EnableInvokeDynamic) {
2055 - initialize_wk_klasses_through(indy_group_end, scan, CHECK);
2056 - }
2057 - if (_well_known_klasses[indy_group_start] == NULL) {
2058 - // Skip the rest of the dynamic typing classes, if Linkage is not loaded.
2059 - scan = WKID(indy_group_end+1);
2046 + initialize_wk_klasses_through(jsr292_group_end, scan, CHECK);
2047 + } else {
2048 + // Skip the JSR 292 classes, if not enabled.
2049 + scan = WKID(jsr292_group_end + 1);
2060 2050 }
2061 2051
2062 2052 initialize_wk_klasses_until(WKID_LIMIT, scan, CHECK);
2063 2053
2064 2054 _box_klasses[T_BOOLEAN] = WK_KLASS(Boolean_klass);
2065 2055 _box_klasses[T_CHAR] = WK_KLASS(Character_klass);
2066 2056 _box_klasses[T_FLOAT] = WK_KLASS(Float_klass);
2067 2057 _box_klasses[T_DOUBLE] = WK_KLASS(Double_klass);
2068 2058 _box_klasses[T_BYTE] = WK_KLASS(Byte_klass);
2069 2059 _box_klasses[T_SHORT] = WK_KLASS(Short_klass);
2070 2060 _box_klasses[T_INT] = WK_KLASS(Integer_klass);
2071 2061 _box_klasses[T_LONG] = WK_KLASS(Long_klass);
2072 2062 //_box_klasses[T_OBJECT] = WK_KLASS(object_klass);
2073 2063 //_box_klasses[T_ARRAY] = WK_KLASS(object_klass);
2074 2064
2075 2065 #ifdef KERNEL
2076 2066 if (sun_jkernel_DownloadManager_klass() == NULL) {
2077 2067 warning("Cannot find sun/jkernel/DownloadManager");
2078 2068 }
2079 2069 #endif // KERNEL
2080 2070
2081 2071 { // Compute whether we should use loadClass or loadClassInternal when loading classes.
2082 2072 methodOop method = instanceKlass::cast(ClassLoader_klass())->find_method(vmSymbols::loadClassInternal_name(), vmSymbols::string_class_signature());
2083 2073 _has_loadClassInternal = (method != NULL);
2084 2074 }
2085 2075 { // Compute whether we should use checkPackageAccess or NOT
2086 2076 methodOop method = instanceKlass::cast(ClassLoader_klass())->find_method(vmSymbols::checkPackageAccess_name(), vmSymbols::class_protectiondomain_signature());
2087 2077 _has_checkPackageAccess = (method != NULL);
2088 2078 }
2089 2079 }
2090 2080
2091 2081 // Tells if a given klass is a box (wrapper class, such as java.lang.Integer).
2092 2082 // If so, returns the basic type it holds. If not, returns T_OBJECT.
2093 2083 BasicType SystemDictionary::box_klass_type(klassOop k) {
2094 2084 assert(k != NULL, "");
2095 2085 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
2096 2086 if (_box_klasses[i] == k)
2097 2087 return (BasicType)i;
2098 2088 }
2099 2089 return T_OBJECT;
2100 2090 }
2101 2091
2102 2092 KlassHandle SystemDictionaryHandles::box_klass(BasicType t) {
2103 2093 if (t >= T_BOOLEAN && t <= T_VOID)
2104 2094 return KlassHandle(&SystemDictionary::_box_klasses[t], true);
2105 2095 else
2106 2096 return KlassHandle();
2107 2097 }
2108 2098
2109 2099 // Constraints on class loaders. The details of the algorithm can be
2110 2100 // found in the OOPSLA'98 paper "Dynamic Class Loading in the Java
2111 2101 // Virtual Machine" by Sheng Liang and Gilad Bracha. The basic idea is
2112 2102 // that the system dictionary needs to maintain a set of contraints that
2113 2103 // must be satisfied by all classes in the dictionary.
2114 2104 // if defining is true, then LinkageError if already in systemDictionary
2115 2105 // if initiating loader, then ok if instanceKlass matches existing entry
2116 2106
2117 2107 void SystemDictionary::check_constraints(int d_index, unsigned int d_hash,
2118 2108 instanceKlassHandle k,
2119 2109 Handle class_loader, bool defining,
2120 2110 TRAPS) {
2121 2111 const char *linkage_error = NULL;
2122 2112 {
2123 2113 Symbol* name = k->name();
2124 2114 MutexLocker mu(SystemDictionary_lock, THREAD);
2125 2115
2126 2116 klassOop check = find_class(d_index, d_hash, name, class_loader);
2127 2117 if (check != (klassOop)NULL) {
2128 2118 // if different instanceKlass - duplicate class definition,
2129 2119 // else - ok, class loaded by a different thread in parallel,
2130 2120 // we should only have found it if it was done loading and ok to use
2131 2121 // system dictionary only holds instance classes, placeholders
2132 2122 // also holds array classes
2133 2123
2134 2124 assert(check->klass_part()->oop_is_instance(), "noninstance in systemdictionary");
2135 2125 if ((defining == true) || (k() != check)) {
2136 2126 linkage_error = "loader (instance of %s): attempted duplicate class "
2137 2127 "definition for name: \"%s\"";
2138 2128 } else {
2139 2129 return;
2140 2130 }
2141 2131 }
2142 2132
2143 2133 #ifdef ASSERT
2144 2134 Symbol* ph_check = find_placeholder(name, class_loader);
2145 2135 assert(ph_check == NULL || ph_check == name, "invalid symbol");
2146 2136 #endif
2147 2137
2148 2138 if (linkage_error == NULL) {
2149 2139 if (constraints()->check_or_update(k, class_loader, name) == false) {
2150 2140 linkage_error = "loader constraint violation: loader (instance of %s)"
2151 2141 " previously initiated loading for a different type with name \"%s\"";
2152 2142 }
2153 2143 }
2154 2144 }
2155 2145
2156 2146 // Throw error now if needed (cannot throw while holding
2157 2147 // SystemDictionary_lock because of rank ordering)
2158 2148
2159 2149 if (linkage_error) {
2160 2150 ResourceMark rm(THREAD);
2161 2151 const char* class_loader_name = loader_name(class_loader());
2162 2152 char* type_name = k->name()->as_C_string();
2163 2153 size_t buflen = strlen(linkage_error) + strlen(class_loader_name) +
2164 2154 strlen(type_name);
2165 2155 char* buf = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, buflen);
2166 2156 jio_snprintf(buf, buflen, linkage_error, class_loader_name, type_name);
2167 2157 THROW_MSG(vmSymbols::java_lang_LinkageError(), buf);
2168 2158 }
2169 2159 }
2170 2160
2171 2161
2172 2162 // Update system dictionary - done after check_constraint and add_to_hierachy
2173 2163 // have been called.
2174 2164 void SystemDictionary::update_dictionary(int d_index, unsigned int d_hash,
2175 2165 int p_index, unsigned int p_hash,
2176 2166 instanceKlassHandle k,
2177 2167 Handle class_loader,
2178 2168 TRAPS) {
2179 2169 // Compile_lock prevents systemDictionary updates during compilations
2180 2170 assert_locked_or_safepoint(Compile_lock);
2181 2171 Symbol* name = k->name();
2182 2172
2183 2173 {
2184 2174 MutexLocker mu1(SystemDictionary_lock, THREAD);
2185 2175
2186 2176 // See whether biased locking is enabled and if so set it for this
2187 2177 // klass.
2188 2178 // Note that this must be done past the last potential blocking
2189 2179 // point / safepoint. We enable biased locking lazily using a
2190 2180 // VM_Operation to iterate the SystemDictionary and installing the
2191 2181 // biasable mark word into each instanceKlass's prototype header.
2192 2182 // To avoid race conditions where we accidentally miss enabling the
2193 2183 // optimization for one class in the process of being added to the
2194 2184 // dictionary, we must not safepoint after the test of
2195 2185 // BiasedLocking::enabled().
2196 2186 if (UseBiasedLocking && BiasedLocking::enabled()) {
2197 2187 // Set biased locking bit for all loaded classes; it will be
2198 2188 // cleared if revocation occurs too often for this type
2199 2189 // NOTE that we must only do this when the class is initally
2200 2190 // defined, not each time it is referenced from a new class loader
2201 2191 if (k->class_loader() == class_loader()) {
2202 2192 k->set_prototype_header(markOopDesc::biased_locking_prototype());
2203 2193 }
2204 2194 }
2205 2195
2206 2196 // Check for a placeholder. If there, remove it and make a
2207 2197 // new system dictionary entry.
2208 2198 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD);
2209 2199 klassOop sd_check = find_class(d_index, d_hash, name, class_loader);
2210 2200 if (sd_check == NULL) {
2211 2201 dictionary()->add_klass(name, class_loader, k);
2212 2202 notice_modification();
2213 2203 }
2214 2204 #ifdef ASSERT
2215 2205 sd_check = find_class(d_index, d_hash, name, class_loader);
2216 2206 assert (sd_check != NULL, "should have entry in system dictionary");
2217 2207 // Changed to allow PH to remain to complete class circularity checking
2218 2208 // while only one thread can define a class at one time, multiple
2219 2209 // classes can resolve the superclass for a class at one time,
2220 2210 // and the placeholder is used to track that
2221 2211 // Symbol* ph_check = find_placeholder(name, class_loader);
2222 2212 // assert (ph_check == NULL, "should not have a placeholder entry");
2223 2213 #endif
2224 2214 SystemDictionary_lock->notify_all();
2225 2215 }
2226 2216 }
2227 2217
2228 2218
2229 2219 // Try to find a class name using the loader constraints. The
2230 2220 // loader constraints might know about a class that isn't fully loaded
2231 2221 // yet and these will be ignored.
2232 2222 klassOop SystemDictionary::find_constrained_instance_or_array_klass(
2233 2223 Symbol* class_name, Handle class_loader, TRAPS) {
2234 2224
2235 2225 // First see if it has been loaded directly.
2236 2226 // Force the protection domain to be null. (This removes protection checks.)
2237 2227 Handle no_protection_domain;
2238 2228 klassOop klass = find_instance_or_array_klass(class_name, class_loader,
2239 2229 no_protection_domain, CHECK_NULL);
2240 2230 if (klass != NULL)
2241 2231 return klass;
2242 2232
2243 2233 // Now look to see if it has been loaded elsewhere, and is subject to
2244 2234 // a loader constraint that would require this loader to return the
2245 2235 // klass that is already loaded.
2246 2236 if (FieldType::is_array(class_name)) {
2247 2237 // For array classes, their klassOops are not kept in the
2248 2238 // constraint table. The element klassOops are.
2249 2239 FieldArrayInfo fd;
2250 2240 BasicType t = FieldType::get_array_info(class_name, fd, CHECK_(NULL));
2251 2241 if (t != T_OBJECT) {
2252 2242 klass = Universe::typeArrayKlassObj(t);
2253 2243 } else {
2254 2244 MutexLocker mu(SystemDictionary_lock, THREAD);
2255 2245 klass = constraints()->find_constrained_klass(fd.object_key(), class_loader);
2256 2246 }
2257 2247 // If element class already loaded, allocate array klass
2258 2248 if (klass != NULL) {
2259 2249 klass = Klass::cast(klass)->array_klass_or_null(fd.dimension());
2260 2250 }
2261 2251 } else {
2262 2252 MutexLocker mu(SystemDictionary_lock, THREAD);
2263 2253 // Non-array classes are easy: simply check the constraint table.
2264 2254 klass = constraints()->find_constrained_klass(class_name, class_loader);
2265 2255 }
2266 2256
2267 2257 return klass;
2268 2258 }
2269 2259
2270 2260
2271 2261 bool SystemDictionary::add_loader_constraint(Symbol* class_name,
2272 2262 Handle class_loader1,
2273 2263 Handle class_loader2,
2274 2264 Thread* THREAD) {
2275 2265 Symbol* constraint_name = NULL;
2276 2266 if (!FieldType::is_array(class_name)) {
2277 2267 constraint_name = class_name;
2278 2268 } else {
2279 2269 // For array classes, their klassOops are not kept in the
2280 2270 // constraint table. The element classes are.
2281 2271 FieldArrayInfo fd;
2282 2272 BasicType t = FieldType::get_array_info(class_name, fd, CHECK_(false));
2283 2273 // primitive types always pass
2284 2274 if (t != T_OBJECT) {
2285 2275 return true;
2286 2276 } else {
2287 2277 constraint_name = fd.object_key();
2288 2278 }
2289 2279 }
2290 2280 unsigned int d_hash1 = dictionary()->compute_hash(constraint_name, class_loader1);
2291 2281 int d_index1 = dictionary()->hash_to_index(d_hash1);
2292 2282
2293 2283 unsigned int d_hash2 = dictionary()->compute_hash(constraint_name, class_loader2);
2294 2284 int d_index2 = dictionary()->hash_to_index(d_hash2);
2295 2285 {
2296 2286 MutexLocker mu_s(SystemDictionary_lock, THREAD);
2297 2287
2298 2288 // Better never do a GC while we're holding these oops
2299 2289 No_Safepoint_Verifier nosafepoint;
2300 2290
2301 2291 klassOop klass1 = find_class(d_index1, d_hash1, constraint_name, class_loader1);
2302 2292 klassOop klass2 = find_class(d_index2, d_hash2, constraint_name, class_loader2);
2303 2293 return constraints()->add_entry(constraint_name, klass1, class_loader1,
2304 2294 klass2, class_loader2);
2305 2295 }
2306 2296 }
2307 2297
2308 2298 // Add entry to resolution error table to record the error when the first
2309 2299 // attempt to resolve a reference to a class has failed.
2310 2300 void SystemDictionary::add_resolution_error(constantPoolHandle pool, int which, Symbol* error) {
2311 2301 unsigned int hash = resolution_errors()->compute_hash(pool, which);
2312 2302 int index = resolution_errors()->hash_to_index(hash);
2313 2303 {
2314 2304 MutexLocker ml(SystemDictionary_lock, Thread::current());
2315 2305 resolution_errors()->add_entry(index, hash, pool, which, error);
2316 2306 }
2317 2307 }
2318 2308
2319 2309 // Lookup resolution error table. Returns error if found, otherwise NULL.
2320 2310 Symbol* SystemDictionary::find_resolution_error(constantPoolHandle pool, int which) {
2321 2311 unsigned int hash = resolution_errors()->compute_hash(pool, which);
2322 2312 int index = resolution_errors()->hash_to_index(hash);
2323 2313 {
2324 2314 MutexLocker ml(SystemDictionary_lock, Thread::current());
2325 2315 ResolutionErrorEntry* entry = resolution_errors()->find_entry(index, hash, pool, which);
2326 2316 return (entry != NULL) ? entry->error() : (Symbol*)NULL;
2327 2317 }
2328 2318 }
2329 2319
2330 2320
2331 2321 // Signature constraints ensure that callers and callees agree about
2332 2322 // the meaning of type names in their signatures. This routine is the
2333 2323 // intake for constraints. It collects them from several places:
2334 2324 //
2335 2325 // * LinkResolver::resolve_method (if check_access is true) requires
2336 2326 // that the resolving class (the caller) and the defining class of
2337 2327 // the resolved method (the callee) agree on each type in the
2338 2328 // method's signature.
2339 2329 //
2340 2330 // * LinkResolver::resolve_interface_method performs exactly the same
2341 2331 // checks.
2342 2332 //
2343 2333 // * LinkResolver::resolve_field requires that the constant pool
2344 2334 // attempting to link to a field agree with the field's defining
2345 2335 // class about the type of the field signature.
2346 2336 //
2347 2337 // * klassVtable::initialize_vtable requires that, when a class
2348 2338 // overrides a vtable entry allocated by a superclass, that the
2349 2339 // overriding method (i.e., the callee) agree with the superclass
2350 2340 // on each type in the method's signature.
2351 2341 //
2352 2342 // * klassItable::initialize_itable requires that, when a class fills
2353 2343 // in its itables, for each non-abstract method installed in an
2354 2344 // itable, the method (i.e., the callee) agree with the interface
2355 2345 // on each type in the method's signature.
2356 2346 //
2357 2347 // All those methods have a boolean (check_access, checkconstraints)
2358 2348 // which turns off the checks. This is used from specialized contexts
2359 2349 // such as bootstrapping, dumping, and debugging.
2360 2350 //
2361 2351 // No direct constraint is placed between the class and its
2362 2352 // supertypes. Constraints are only placed along linked relations
2363 2353 // between callers and callees. When a method overrides or implements
2364 2354 // an abstract method in a supertype (superclass or interface), the
2365 2355 // constraints are placed as if the supertype were the caller to the
2366 2356 // overriding method. (This works well, since callers to the
2367 2357 // supertype have already established agreement between themselves and
2368 2358 // the supertype.) As a result of all this, a class can disagree with
2369 2359 // its supertype about the meaning of a type name, as long as that
2370 2360 // class neither calls a relevant method of the supertype, nor is
2371 2361 // called (perhaps via an override) from the supertype.
2372 2362 //
2373 2363 //
2374 2364 // SystemDictionary::check_signature_loaders(sig, l1, l2)
2375 2365 //
2376 2366 // Make sure all class components (including arrays) in the given
2377 2367 // signature will be resolved to the same class in both loaders.
2378 2368 // Returns the name of the type that failed a loader constraint check, or
2379 2369 // NULL if no constraint failed. The returned C string needs cleaning up
2380 2370 // with a ResourceMark in the caller. No exception except OOME is thrown.
2381 2371 // Arrays are not added to the loader constraint table, their elements are.
2382 2372 char* SystemDictionary::check_signature_loaders(Symbol* signature,
2383 2373 Handle loader1, Handle loader2,
2384 2374 bool is_method, TRAPS) {
2385 2375 // Nothing to do if loaders are the same.
2386 2376 if (loader1() == loader2()) {
2387 2377 return NULL;
2388 2378 }
2389 2379
2390 2380 ResourceMark rm(THREAD);
2391 2381 SignatureStream sig_strm(signature, is_method);
2392 2382 while (!sig_strm.is_done()) {
2393 2383 if (sig_strm.is_object()) {
2394 2384 Symbol* s = sig_strm.as_symbol(CHECK_NULL);
2395 2385 Symbol* sig = s;
2396 2386 if (!add_loader_constraint(sig, loader1, loader2, THREAD)) {
2397 2387 return sig->as_C_string();
2398 2388 }
2399 2389 }
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2400 2390 sig_strm.next();
2401 2391 }
2402 2392 return NULL;
2403 2393 }
2404 2394
2405 2395
2406 2396 methodOop SystemDictionary::find_method_handle_invoke(Symbol* name,
2407 2397 Symbol* signature,
2408 2398 KlassHandle accessing_klass,
2409 2399 TRAPS) {
2410 - if (!EnableMethodHandles) return NULL;
2400 + if (!EnableInvokeDynamic) return NULL;
2411 2401 vmSymbols::SID name_id = vmSymbols::find_sid(name);
2412 2402 assert(name_id != vmSymbols::NO_SID, "must be a known name");
2413 2403 unsigned int hash = invoke_method_table()->compute_hash(signature, name_id);
2414 2404 int index = invoke_method_table()->hash_to_index(hash);
2415 2405 SymbolPropertyEntry* spe = invoke_method_table()->find_entry(index, hash, signature, name_id);
2416 2406 methodHandle non_cached_result;
2417 2407 if (spe == NULL || spe->property_oop() == NULL) {
2418 2408 spe = NULL;
2419 2409 // Must create lots of stuff here, but outside of the SystemDictionary lock.
2420 2410 if (THREAD->is_Compiler_thread())
2421 2411 return NULL; // do not attempt from within compiler
2422 2412 bool for_invokeGeneric = (name_id == vmSymbols::VM_SYMBOL_ENUM_NAME(invokeGeneric_name));
2423 2413 if (AllowInvokeForInvokeGeneric && name_id == vmSymbols::VM_SYMBOL_ENUM_NAME(invoke_name))
2424 2414 for_invokeGeneric = true;
2425 2415 bool found_on_bcp = false;
2426 2416 Handle mt = find_method_handle_type(signature, accessing_klass,
2427 2417 for_invokeGeneric,
2428 2418 found_on_bcp, CHECK_NULL);
2429 2419 KlassHandle mh_klass = SystemDictionaryHandles::MethodHandle_klass();
2430 2420 methodHandle m = methodOopDesc::make_invoke_method(mh_klass, name, signature,
2431 2421 mt, CHECK_NULL);
2432 2422 // Now grab the lock. We might have to throw away the new method,
2433 2423 // if a racing thread has managed to install one at the same time.
2434 2424 if (found_on_bcp) {
2435 2425 MutexLocker ml(SystemDictionary_lock, Thread::current());
2436 2426 spe = invoke_method_table()->find_entry(index, hash, signature, name_id);
2437 2427 if (spe == NULL)
2438 2428 spe = invoke_method_table()->add_entry(index, hash, signature, name_id);
2439 2429 if (spe->property_oop() == NULL)
2440 2430 spe->set_property_oop(m());
2441 2431 } else {
2442 2432 non_cached_result = m;
2443 2433 }
2444 2434 }
2445 2435 if (spe != NULL && spe->property_oop() != NULL) {
2446 2436 assert(spe->property_oop()->is_method(), "");
2447 2437 return (methodOop) spe->property_oop();
2448 2438 } else {
2449 2439 return non_cached_result();
2450 2440 }
2451 2441 }
2452 2442
2453 2443 // Ask Java code to find or construct a java.lang.invoke.MethodType for the given
2454 2444 // signature, as interpreted relative to the given class loader.
2455 2445 // Because of class loader constraints, all method handle usage must be
2456 2446 // consistent with this loader.
2457 2447 Handle SystemDictionary::find_method_handle_type(Symbol* signature,
2458 2448 KlassHandle accessing_klass,
2459 2449 bool for_invokeGeneric,
2460 2450 bool& return_bcp_flag,
2461 2451 TRAPS) {
2462 2452 Handle class_loader, protection_domain;
2463 2453 bool is_on_bcp = true; // keep this true as long as we can materialize from the boot classloader
2464 2454 Handle empty;
2465 2455 int npts = ArgumentCount(signature).size();
2466 2456 objArrayHandle pts = oopFactory::new_objArray(SystemDictionary::Class_klass(), npts, CHECK_(empty));
2467 2457 int arg = 0;
2468 2458 Handle rt; // the return type from the signature
2469 2459 ResourceMark rm(THREAD);
2470 2460 for (SignatureStream ss(signature); !ss.is_done(); ss.next()) {
2471 2461 oop mirror = NULL;
2472 2462 if (is_on_bcp) {
2473 2463 mirror = ss.as_java_mirror(class_loader, protection_domain,
2474 2464 SignatureStream::ReturnNull, CHECK_(empty));
2475 2465 if (mirror == NULL) {
2476 2466 // fall back from BCP to accessing_klass
2477 2467 if (accessing_klass.not_null()) {
2478 2468 class_loader = Handle(THREAD, instanceKlass::cast(accessing_klass())->class_loader());
2479 2469 protection_domain = Handle(THREAD, instanceKlass::cast(accessing_klass())->protection_domain());
2480 2470 }
2481 2471 is_on_bcp = false;
2482 2472 }
2483 2473 }
2484 2474 if (!is_on_bcp) {
2485 2475 // Resolve, throwing a real error if it doesn't work.
2486 2476 mirror = ss.as_java_mirror(class_loader, protection_domain,
2487 2477 SignatureStream::NCDFError, CHECK_(empty));
2488 2478 }
2489 2479 if (ss.at_return_type())
2490 2480 rt = Handle(THREAD, mirror);
2491 2481 else
2492 2482 pts->obj_at_put(arg++, mirror);
2493 2483 // Check accessibility.
2494 2484 if (ss.is_object() && accessing_klass.not_null()) {
2495 2485 klassOop sel_klass = java_lang_Class::as_klassOop(mirror);
2496 2486 // Emulate constantPoolOopDesc::verify_constant_pool_resolve.
2497 2487 if (Klass::cast(sel_klass)->oop_is_objArray())
2498 2488 sel_klass = objArrayKlass::cast(sel_klass)->bottom_klass();
2499 2489 if (Klass::cast(sel_klass)->oop_is_instance()) {
2500 2490 KlassHandle sel_kh(THREAD, sel_klass);
2501 2491 LinkResolver::check_klass_accessability(accessing_klass, sel_kh, CHECK_(empty));
2502 2492 }
2503 2493 }
2504 2494 }
2505 2495 assert(arg == npts, "");
2506 2496
2507 2497 // call java.lang.invoke.MethodHandleNatives::findMethodType(Class rt, Class[] pts) -> MethodType
2508 2498 JavaCallArguments args(Handle(THREAD, rt()));
2509 2499 args.push_oop(pts());
2510 2500 JavaValue result(T_OBJECT);
2511 2501 Symbol* findMethodHandleType_signature = vmSymbols::findMethodHandleType_signature();
2512 2502 if (AllowTransitionalJSR292 && SystemDictionaryHandles::MethodType_klass()->name() == vmSymbols::java_dyn_MethodType()) {
2513 2503 findMethodHandleType_signature = vmSymbols::findMethodHandleType_TRANS_signature();
2514 2504 }
2515 2505 JavaCalls::call_static(&result,
2516 2506 SystemDictionary::MethodHandleNatives_klass(),
2517 2507 vmSymbols::findMethodHandleType_name(),
2518 2508 findMethodHandleType_signature,
2519 2509 &args, CHECK_(empty));
2520 2510 Handle method_type(THREAD, (oop) result.get_jobject());
2521 2511
2522 2512 if (for_invokeGeneric) {
2523 2513 // call java.lang.invoke.MethodHandleNatives::notifyGenericMethodType(MethodType) -> void
2524 2514 JavaCallArguments args(Handle(THREAD, method_type()));
2525 2515 JavaValue no_result(T_VOID);
2526 2516 Symbol* notifyGenericMethodType_signature = vmSymbols::notifyGenericMethodType_signature();
2527 2517 if (AllowTransitionalJSR292 && SystemDictionaryHandles::MethodType_klass()->name() == vmSymbols::java_dyn_MethodType()) {
2528 2518 notifyGenericMethodType_signature = vmSymbols::notifyGenericMethodType_TRANS_signature();
2529 2519 }
2530 2520 JavaCalls::call_static(&no_result,
2531 2521 SystemDictionary::MethodHandleNatives_klass(),
2532 2522 vmSymbols::notifyGenericMethodType_name(),
2533 2523 notifyGenericMethodType_signature,
2534 2524 &args, THREAD);
2535 2525 if (HAS_PENDING_EXCEPTION) {
2536 2526 // If the notification fails, just kill it.
2537 2527 CLEAR_PENDING_EXCEPTION;
2538 2528 }
2539 2529 }
2540 2530
2541 2531 // report back to the caller with the MethodType and the "on_bcp" flag
2542 2532 return_bcp_flag = is_on_bcp;
2543 2533 return method_type;
2544 2534 }
2545 2535
2546 2536 // Ask Java code to find or construct a method handle constant.
2547 2537 Handle SystemDictionary::link_method_handle_constant(KlassHandle caller,
2548 2538 int ref_kind, //e.g., JVM_REF_invokeVirtual
2549 2539 KlassHandle callee,
2550 2540 Symbol* name_sym,
2551 2541 Symbol* signature,
2552 2542 TRAPS) {
2553 2543 Handle empty;
2554 2544 Handle name = java_lang_String::create_from_symbol(name_sym, CHECK_(empty));
2555 2545 Handle type;
2556 2546 if (signature->utf8_length() > 0 && signature->byte_at(0) == '(') {
2557 2547 bool ignore_is_on_bcp = false;
2558 2548 type = find_method_handle_type(signature, caller, false, ignore_is_on_bcp, CHECK_(empty));
2559 2549 } else {
2560 2550 ResourceMark rm(THREAD);
2561 2551 SignatureStream ss(signature, false);
2562 2552 if (!ss.is_done()) {
2563 2553 oop mirror = ss.as_java_mirror(caller->class_loader(), caller->protection_domain(),
2564 2554 SignatureStream::NCDFError, CHECK_(empty));
2565 2555 type = Handle(THREAD, mirror);
2566 2556 ss.next();
2567 2557 if (!ss.is_done()) type = Handle(); // error!
2568 2558 }
2569 2559 }
2570 2560 if (type.is_null()) {
2571 2561 THROW_MSG_(vmSymbols::java_lang_LinkageError(), "bad signature", empty);
2572 2562 }
2573 2563
2574 2564 // call java.lang.invoke.MethodHandleNatives::linkMethodHandleConstant(Class caller, int refKind, Class callee, String name, Object type) -> MethodHandle
2575 2565 JavaCallArguments args;
2576 2566 args.push_oop(caller->java_mirror()); // the referring class
2577 2567 args.push_int(ref_kind);
2578 2568 args.push_oop(callee->java_mirror()); // the target class
2579 2569 args.push_oop(name());
2580 2570 args.push_oop(type());
2581 2571 JavaValue result(T_OBJECT);
2582 2572 Symbol* linkMethodHandleConstant_signature = vmSymbols::linkMethodHandleConstant_signature();
2583 2573 if (AllowTransitionalJSR292 && SystemDictionaryHandles::MethodHandle_klass()->name() == vmSymbols::java_dyn_MethodHandle()) {
2584 2574 linkMethodHandleConstant_signature = vmSymbols::linkMethodHandleConstant_TRANS_signature();
2585 2575 }
2586 2576 JavaCalls::call_static(&result,
2587 2577 SystemDictionary::MethodHandleNatives_klass(),
2588 2578 vmSymbols::linkMethodHandleConstant_name(),
2589 2579 linkMethodHandleConstant_signature,
2590 2580 &args, CHECK_(empty));
2591 2581 return Handle(THREAD, (oop) result.get_jobject());
2592 2582 }
2593 2583
2594 2584 // Ask Java code to find or construct a java.lang.invoke.CallSite for the given
2595 2585 // name and signature, as interpreted relative to the given class loader.
2596 2586 Handle SystemDictionary::make_dynamic_call_site(Handle bootstrap_method,
2597 2587 Symbol* name,
2598 2588 methodHandle signature_invoker,
2599 2589 Handle info,
2600 2590 methodHandle caller_method,
2601 2591 int caller_bci,
2602 2592 TRAPS) {
2603 2593 Handle empty;
2604 2594 guarantee(bootstrap_method.not_null() &&
2605 2595 java_lang_invoke_MethodHandle::is_instance(bootstrap_method()),
2606 2596 "caller must supply a valid BSM");
2607 2597
2608 2598 Handle caller_mname = MethodHandles::new_MemberName(CHECK_(empty));
2609 2599 MethodHandles::init_MemberName(caller_mname(), caller_method());
2610 2600
2611 2601 // call java.lang.invoke.MethodHandleNatives::makeDynamicCallSite(bootm, name, mtype, info, caller_mname, caller_pos)
2612 2602 oop name_str_oop = StringTable::intern(name, CHECK_(empty)); // not a handle!
2613 2603 JavaCallArguments args(Handle(THREAD, bootstrap_method()));
2614 2604 args.push_oop(name_str_oop);
2615 2605 args.push_oop(signature_invoker->method_handle_type());
2616 2606 args.push_oop(info());
2617 2607 args.push_oop(caller_mname());
2618 2608 args.push_int(caller_bci);
2619 2609 JavaValue result(T_OBJECT);
2620 2610 Symbol* makeDynamicCallSite_signature = vmSymbols::makeDynamicCallSite_signature();
2621 2611 if (AllowTransitionalJSR292 && SystemDictionaryHandles::MethodHandleNatives_klass()->name() == vmSymbols::sun_dyn_MethodHandleNatives()) {
2622 2612 makeDynamicCallSite_signature = vmSymbols::makeDynamicCallSite_TRANS_signature();
2623 2613 }
2624 2614 if (AllowTransitionalJSR292 && SystemDictionaryHandles::MethodHandleNatives_klass()->name() == vmSymbols::java_dyn_MethodHandleNatives()) {
2625 2615 makeDynamicCallSite_signature = vmSymbols::makeDynamicCallSite_TRANS2_signature();
2626 2616 }
2627 2617 JavaCalls::call_static(&result,
2628 2618 SystemDictionary::MethodHandleNatives_klass(),
2629 2619 vmSymbols::makeDynamicCallSite_name(),
2630 2620 makeDynamicCallSite_signature,
2631 2621 &args, CHECK_(empty));
2632 2622 oop call_site_oop = (oop) result.get_jobject();
2633 2623 assert(call_site_oop->is_oop()
2634 2624 /*&& java_lang_invoke_CallSite::is_instance(call_site_oop)*/, "must be sane");
2635 2625 if (TraceMethodHandles) {
2636 2626 #ifndef PRODUCT
2637 2627 tty->print_cr("Linked invokedynamic bci=%d site="INTPTR_FORMAT":", caller_bci, call_site_oop);
2638 2628 call_site_oop->print();
2639 2629 tty->cr();
2640 2630 #endif //PRODUCT
2641 2631 }
2642 2632 return call_site_oop;
2643 2633 }
2644 2634
2645 2635 Handle SystemDictionary::find_bootstrap_method(methodHandle caller_method, int caller_bci,
2646 2636 int cache_index,
2647 2637 Handle& argument_info_result,
2648 2638 TRAPS) {
2649 2639 Handle empty;
2650 2640
2651 2641 constantPoolHandle pool;
2652 2642 {
2653 2643 klassOop caller = caller_method->method_holder();
2654 2644 if (!Klass::cast(caller)->oop_is_instance()) return empty;
2655 2645 pool = constantPoolHandle(THREAD, instanceKlass::cast(caller)->constants());
2656 2646 }
2657 2647
2658 2648 int constant_pool_index = pool->cache()->entry_at(cache_index)->constant_pool_index();
2659 2649 constantTag tag = pool->tag_at(constant_pool_index);
2660 2650
2661 2651 if (tag.is_invoke_dynamic()) {
2662 2652 // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
2663 2653 // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
2664 2654 int bsm_index = pool->invoke_dynamic_bootstrap_method_ref_index_at(constant_pool_index);
2665 2655 if (bsm_index != 0) {
2666 2656 int bsm_index_in_cache = pool->cache()->entry_at(cache_index)->bootstrap_method_index_in_cache();
2667 2657 DEBUG_ONLY(int bsm_index_2 = pool->cache()->entry_at(bsm_index_in_cache)->constant_pool_index());
2668 2658 assert(bsm_index == bsm_index_2, "BSM constant lifted to cache");
2669 2659 if (TraceMethodHandles) {
2670 2660 tty->print_cr("resolving bootstrap method for "PTR_FORMAT" at %d at cache[%d]CP[%d]...",
2671 2661 (intptr_t) caller_method(), caller_bci, cache_index, constant_pool_index);
2672 2662 }
2673 2663 oop bsm_oop = pool->resolve_cached_constant_at(bsm_index_in_cache, CHECK_(empty));
2674 2664 if (TraceMethodHandles) {
2675 2665 tty->print_cr("bootstrap method for "PTR_FORMAT" at %d retrieved as "PTR_FORMAT":",
2676 2666 (intptr_t) caller_method(), caller_bci, (intptr_t) bsm_oop);
2677 2667 }
2678 2668 assert(bsm_oop->is_oop(), "must be sane");
2679 2669 // caller must verify that it is of type MethodHandle
2680 2670 Handle bsm(THREAD, bsm_oop);
2681 2671 bsm_oop = NULL; // safety
2682 2672
2683 2673 // Extract the optional static arguments.
2684 2674 Handle argument_info; // either null, or one arg, or Object[]{arg...}
2685 2675 int argc = pool->invoke_dynamic_argument_count_at(constant_pool_index);
2686 2676 if (TraceInvokeDynamic) {
2687 2677 tty->print_cr("find_bootstrap_method: [%d/%d] CONSTANT_InvokeDynamic: %d[%d]",
2688 2678 constant_pool_index, cache_index, bsm_index, argc);
2689 2679 }
2690 2680 if (argc > 0) {
2691 2681 objArrayHandle arg_array;
2692 2682 if (argc > 1) {
2693 2683 objArrayOop arg_array_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), argc, CHECK_(empty));
2694 2684 arg_array = objArrayHandle(THREAD, arg_array_oop);
2695 2685 argument_info = arg_array;
2696 2686 }
2697 2687 for (int arg_i = 0; arg_i < argc; arg_i++) {
2698 2688 int arg_index = pool->invoke_dynamic_argument_index_at(constant_pool_index, arg_i);
2699 2689 oop arg_oop = pool->resolve_possibly_cached_constant_at(arg_index, CHECK_(empty));
2700 2690 if (arg_array.is_null()) {
2701 2691 argument_info = Handle(THREAD, arg_oop);
2702 2692 } else {
2703 2693 arg_array->obj_at_put(arg_i, arg_oop);
2704 2694 }
2705 2695 }
2706 2696 }
2707 2697
2708 2698 argument_info_result = argument_info; // return argument_info to caller
2709 2699 return bsm;
2710 2700 }
2711 2701 // else null BSM; fall through
2712 2702 } else if (tag.is_name_and_type()) {
2713 2703 // JSR 292 EDR does not have JVM_CONSTANT_InvokeDynamic
2714 2704 // a bare name&type defaults its BSM to null, so fall through...
2715 2705 } else {
2716 2706 ShouldNotReachHere(); // verifier does not allow this
2717 2707 }
2718 2708
2719 2709 // Fall through to pick up the per-class bootstrap method.
2720 2710 // This mechanism may go away in the PFD.
2721 2711 assert(AllowTransitionalJSR292, "else the verifier should have stopped us already");
2722 2712 argument_info_result = empty; // return no argument_info to caller
2723 2713 oop bsm_oop = instanceKlass::cast(caller_method->method_holder())->bootstrap_method();
2724 2714 if (bsm_oop != NULL) {
2725 2715 if (TraceMethodHandles) {
2726 2716 tty->print_cr("bootstrap method for "PTR_FORMAT" registered as "PTR_FORMAT":",
2727 2717 (intptr_t) caller_method(), (intptr_t) bsm_oop);
2728 2718 }
2729 2719 assert(bsm_oop->is_oop(), "must be sane");
2730 2720 return Handle(THREAD, bsm_oop);
2731 2721 }
2732 2722
2733 2723 return empty;
2734 2724 }
2735 2725
2736 2726 // Since the identity hash code for symbols changes when the symbols are
2737 2727 // moved from the regular perm gen (hash in the mark word) to the shared
2738 2728 // spaces (hash is the address), the classes loaded into the dictionary
2739 2729 // may be in the wrong buckets.
2740 2730
2741 2731 void SystemDictionary::reorder_dictionary() {
2742 2732 dictionary()->reorder_dictionary();
2743 2733 }
2744 2734
2745 2735
2746 2736 void SystemDictionary::copy_buckets(char** top, char* end) {
2747 2737 dictionary()->copy_buckets(top, end);
2748 2738 }
2749 2739
2750 2740
2751 2741 void SystemDictionary::copy_table(char** top, char* end) {
2752 2742 dictionary()->copy_table(top, end);
2753 2743 }
2754 2744
2755 2745
2756 2746 void SystemDictionary::reverse() {
2757 2747 dictionary()->reverse();
2758 2748 }
2759 2749
2760 2750 int SystemDictionary::number_of_classes() {
2761 2751 return dictionary()->number_of_entries();
2762 2752 }
2763 2753
2764 2754
2765 2755 // ----------------------------------------------------------------------------
2766 2756 #ifndef PRODUCT
2767 2757
2768 2758 void SystemDictionary::print() {
2769 2759 dictionary()->print();
2770 2760
2771 2761 // Placeholders
2772 2762 GCMutexLocker mu(SystemDictionary_lock);
2773 2763 placeholders()->print();
2774 2764
2775 2765 // loader constraints - print under SD_lock
2776 2766 constraints()->print();
2777 2767 }
2778 2768
2779 2769 #endif
2780 2770
2781 2771 void SystemDictionary::verify() {
2782 2772 guarantee(dictionary() != NULL, "Verify of system dictionary failed");
2783 2773 guarantee(constraints() != NULL,
2784 2774 "Verify of loader constraints failed");
2785 2775 guarantee(dictionary()->number_of_entries() >= 0 &&
2786 2776 placeholders()->number_of_entries() >= 0,
2787 2777 "Verify of system dictionary failed");
2788 2778
2789 2779 // Verify dictionary
2790 2780 dictionary()->verify();
2791 2781
2792 2782 GCMutexLocker mu(SystemDictionary_lock);
2793 2783 placeholders()->verify();
2794 2784
2795 2785 // Verify constraint table
2796 2786 guarantee(constraints() != NULL, "Verify of loader constraints failed");
2797 2787 constraints()->verify(dictionary(), placeholders());
2798 2788 }
2799 2789
2800 2790
2801 2791 void SystemDictionary::verify_obj_klass_present(Handle obj,
2802 2792 Symbol* class_name,
2803 2793 Handle class_loader) {
2804 2794 GCMutexLocker mu(SystemDictionary_lock);
2805 2795 Symbol* name;
2806 2796
2807 2797 klassOop probe = find_class(class_name, class_loader);
2808 2798 if (probe == NULL) {
2809 2799 probe = SystemDictionary::find_shared_class(class_name);
2810 2800 if (probe == NULL) {
2811 2801 name = find_placeholder(class_name, class_loader);
2812 2802 }
2813 2803 }
2814 2804 guarantee(probe != NULL || name != NULL,
2815 2805 "Loaded klasses should be in SystemDictionary");
2816 2806 }
2817 2807
2818 2808 #ifndef PRODUCT
2819 2809
2820 2810 // statistics code
2821 2811 class ClassStatistics: AllStatic {
2822 2812 private:
2823 2813 static int nclasses; // number of classes
2824 2814 static int nmethods; // number of methods
2825 2815 static int nmethoddata; // number of methodData
2826 2816 static int class_size; // size of class objects in words
2827 2817 static int method_size; // size of method objects in words
2828 2818 static int debug_size; // size of debug info in methods
2829 2819 static int methoddata_size; // size of methodData objects in words
2830 2820
2831 2821 static void do_class(klassOop k) {
2832 2822 nclasses++;
2833 2823 class_size += k->size();
2834 2824 if (k->klass_part()->oop_is_instance()) {
2835 2825 instanceKlass* ik = (instanceKlass*)k->klass_part();
2836 2826 class_size += ik->methods()->size();
2837 2827 class_size += ik->constants()->size();
2838 2828 class_size += ik->local_interfaces()->size();
2839 2829 class_size += ik->transitive_interfaces()->size();
2840 2830 // We do not have to count implementors, since we only store one!
2841 2831 class_size += ik->fields()->size();
2842 2832 }
2843 2833 }
2844 2834
2845 2835 static void do_method(methodOop m) {
2846 2836 nmethods++;
2847 2837 method_size += m->size();
2848 2838 // class loader uses same objArray for empty vectors, so don't count these
2849 2839 if (m->exception_table()->length() != 0) method_size += m->exception_table()->size();
2850 2840 if (m->has_stackmap_table()) {
2851 2841 method_size += m->stackmap_data()->size();
2852 2842 }
2853 2843
2854 2844 methodDataOop mdo = m->method_data();
2855 2845 if (mdo != NULL) {
2856 2846 nmethoddata++;
2857 2847 methoddata_size += mdo->size();
2858 2848 }
2859 2849 }
2860 2850
2861 2851 public:
2862 2852 static void print() {
2863 2853 SystemDictionary::classes_do(do_class);
2864 2854 SystemDictionary::methods_do(do_method);
2865 2855 tty->print_cr("Class statistics:");
2866 2856 tty->print_cr("%d classes (%d bytes)", nclasses, class_size * oopSize);
2867 2857 tty->print_cr("%d methods (%d bytes = %d base + %d debug info)", nmethods,
2868 2858 (method_size + debug_size) * oopSize, method_size * oopSize, debug_size * oopSize);
2869 2859 tty->print_cr("%d methoddata (%d bytes)", nmethoddata, methoddata_size * oopSize);
2870 2860 }
2871 2861 };
2872 2862
2873 2863
2874 2864 int ClassStatistics::nclasses = 0;
2875 2865 int ClassStatistics::nmethods = 0;
2876 2866 int ClassStatistics::nmethoddata = 0;
2877 2867 int ClassStatistics::class_size = 0;
2878 2868 int ClassStatistics::method_size = 0;
2879 2869 int ClassStatistics::debug_size = 0;
2880 2870 int ClassStatistics::methoddata_size = 0;
2881 2871
2882 2872 void SystemDictionary::print_class_statistics() {
2883 2873 ResourceMark rm;
2884 2874 ClassStatistics::print();
2885 2875 }
2886 2876
2887 2877
2888 2878 class MethodStatistics: AllStatic {
2889 2879 public:
2890 2880 enum {
2891 2881 max_parameter_size = 10
2892 2882 };
2893 2883 private:
2894 2884
2895 2885 static int _number_of_methods;
2896 2886 static int _number_of_final_methods;
2897 2887 static int _number_of_static_methods;
2898 2888 static int _number_of_native_methods;
2899 2889 static int _number_of_synchronized_methods;
2900 2890 static int _number_of_profiled_methods;
2901 2891 static int _number_of_bytecodes;
2902 2892 static int _parameter_size_profile[max_parameter_size];
2903 2893 static int _bytecodes_profile[Bytecodes::number_of_java_codes];
2904 2894
2905 2895 static void initialize() {
2906 2896 _number_of_methods = 0;
2907 2897 _number_of_final_methods = 0;
2908 2898 _number_of_static_methods = 0;
2909 2899 _number_of_native_methods = 0;
2910 2900 _number_of_synchronized_methods = 0;
2911 2901 _number_of_profiled_methods = 0;
2912 2902 _number_of_bytecodes = 0;
2913 2903 for (int i = 0; i < max_parameter_size ; i++) _parameter_size_profile[i] = 0;
2914 2904 for (int j = 0; j < Bytecodes::number_of_java_codes; j++) _bytecodes_profile [j] = 0;
2915 2905 };
2916 2906
2917 2907 static void do_method(methodOop m) {
2918 2908 _number_of_methods++;
2919 2909 // collect flag info
2920 2910 if (m->is_final() ) _number_of_final_methods++;
2921 2911 if (m->is_static() ) _number_of_static_methods++;
2922 2912 if (m->is_native() ) _number_of_native_methods++;
2923 2913 if (m->is_synchronized()) _number_of_synchronized_methods++;
2924 2914 if (m->method_data() != NULL) _number_of_profiled_methods++;
2925 2915 // collect parameter size info (add one for receiver, if any)
2926 2916 _parameter_size_profile[MIN2(m->size_of_parameters() + (m->is_static() ? 0 : 1), max_parameter_size - 1)]++;
2927 2917 // collect bytecodes info
2928 2918 {
2929 2919 Thread *thread = Thread::current();
2930 2920 HandleMark hm(thread);
2931 2921 BytecodeStream s(methodHandle(thread, m));
2932 2922 Bytecodes::Code c;
2933 2923 while ((c = s.next()) >= 0) {
2934 2924 _number_of_bytecodes++;
2935 2925 _bytecodes_profile[c]++;
2936 2926 }
2937 2927 }
2938 2928 }
2939 2929
2940 2930 public:
2941 2931 static void print() {
2942 2932 initialize();
2943 2933 SystemDictionary::methods_do(do_method);
2944 2934 // generate output
2945 2935 tty->cr();
2946 2936 tty->print_cr("Method statistics (static):");
2947 2937 // flag distribution
2948 2938 tty->cr();
2949 2939 tty->print_cr("%6d final methods %6.1f%%", _number_of_final_methods , _number_of_final_methods * 100.0F / _number_of_methods);
2950 2940 tty->print_cr("%6d static methods %6.1f%%", _number_of_static_methods , _number_of_static_methods * 100.0F / _number_of_methods);
2951 2941 tty->print_cr("%6d native methods %6.1f%%", _number_of_native_methods , _number_of_native_methods * 100.0F / _number_of_methods);
2952 2942 tty->print_cr("%6d synchronized methods %6.1f%%", _number_of_synchronized_methods, _number_of_synchronized_methods * 100.0F / _number_of_methods);
2953 2943 tty->print_cr("%6d profiled methods %6.1f%%", _number_of_profiled_methods, _number_of_profiled_methods * 100.0F / _number_of_methods);
2954 2944 // parameter size profile
2955 2945 tty->cr();
2956 2946 { int tot = 0;
2957 2947 int avg = 0;
2958 2948 for (int i = 0; i < max_parameter_size; i++) {
2959 2949 int n = _parameter_size_profile[i];
2960 2950 tot += n;
2961 2951 avg += n*i;
2962 2952 tty->print_cr("parameter size = %1d: %6d methods %5.1f%%", i, n, n * 100.0F / _number_of_methods);
2963 2953 }
2964 2954 assert(tot == _number_of_methods, "should be the same");
2965 2955 tty->print_cr(" %6d methods 100.0%%", _number_of_methods);
2966 2956 tty->print_cr("(average parameter size = %3.1f including receiver, if any)", (float)avg / _number_of_methods);
2967 2957 }
2968 2958 // bytecodes profile
2969 2959 tty->cr();
2970 2960 { int tot = 0;
2971 2961 for (int i = 0; i < Bytecodes::number_of_java_codes; i++) {
2972 2962 if (Bytecodes::is_defined(i)) {
2973 2963 Bytecodes::Code c = Bytecodes::cast(i);
2974 2964 int n = _bytecodes_profile[c];
2975 2965 tot += n;
2976 2966 tty->print_cr("%9d %7.3f%% %s", n, n * 100.0F / _number_of_bytecodes, Bytecodes::name(c));
2977 2967 }
2978 2968 }
2979 2969 assert(tot == _number_of_bytecodes, "should be the same");
2980 2970 tty->print_cr("%9d 100.000%%", _number_of_bytecodes);
2981 2971 }
2982 2972 tty->cr();
2983 2973 }
2984 2974 };
2985 2975
2986 2976 int MethodStatistics::_number_of_methods;
2987 2977 int MethodStatistics::_number_of_final_methods;
2988 2978 int MethodStatistics::_number_of_static_methods;
2989 2979 int MethodStatistics::_number_of_native_methods;
2990 2980 int MethodStatistics::_number_of_synchronized_methods;
2991 2981 int MethodStatistics::_number_of_profiled_methods;
2992 2982 int MethodStatistics::_number_of_bytecodes;
2993 2983 int MethodStatistics::_parameter_size_profile[MethodStatistics::max_parameter_size];
2994 2984 int MethodStatistics::_bytecodes_profile[Bytecodes::number_of_java_codes];
2995 2985
2996 2986
2997 2987 void SystemDictionary::print_method_statistics() {
2998 2988 MethodStatistics::print();
2999 2989 }
3000 2990
3001 2991 #endif // PRODUCT
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