1 /* 2 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "classfile/javaClasses.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "classfile/verifier.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "compiler/compileBroker.hpp" 31 #include "gc_implementation/shared/markSweep.inline.hpp" 32 #include "gc_interface/collectedHeap.inline.hpp" 33 #include "interpreter/oopMapCache.hpp" 34 #include "interpreter/rewriter.hpp" 35 #include "jvmtifiles/jvmti.h" 36 #include "memory/genOopClosures.inline.hpp" 37 #include "memory/oopFactory.hpp" 38 #include "memory/permGen.hpp" 39 #include "oops/instanceKlass.hpp" 40 #include "oops/instanceMirrorKlass.hpp" 41 #include "oops/instanceOop.hpp" 42 #include "oops/methodOop.hpp" 43 #include "oops/objArrayKlassKlass.hpp" 44 #include "oops/oop.inline.hpp" 45 #include "oops/symbol.hpp" 46 #include "prims/jvmtiExport.hpp" 47 #include "prims/jvmtiRedefineClassesTrace.hpp" 48 #include "runtime/fieldDescriptor.hpp" 49 #include "runtime/handles.inline.hpp" 50 #include "runtime/javaCalls.hpp" 51 #include "runtime/mutexLocker.hpp" 52 #include "services/threadService.hpp" 53 #include "utilities/dtrace.hpp" 54 #ifdef TARGET_OS_FAMILY_linux 55 # include "thread_linux.inline.hpp" 56 #endif 57 #ifdef TARGET_OS_FAMILY_solaris 58 # include "thread_solaris.inline.hpp" 59 #endif 60 #ifdef TARGET_OS_FAMILY_windows 61 # include "thread_windows.inline.hpp" 62 #endif 63 #ifndef SERIALGC 64 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" 65 #include "gc_implementation/g1/g1OopClosures.inline.hpp" 66 #include "gc_implementation/g1/g1RemSet.inline.hpp" 67 #include "gc_implementation/g1/heapRegionSeq.inline.hpp" 68 #include "gc_implementation/parNew/parOopClosures.inline.hpp" 69 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp" 70 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp" 71 #include "oops/oop.pcgc.inline.hpp" 72 #endif 73 #ifdef COMPILER1 74 #include "c1/c1_Compiler.hpp" 75 #endif 76 77 #ifdef DTRACE_ENABLED 78 79 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required, 80 char*, intptr_t, oop, intptr_t); 81 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive, 82 char*, intptr_t, oop, intptr_t, int); 83 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent, 84 char*, intptr_t, oop, intptr_t, int); 85 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous, 86 char*, intptr_t, oop, intptr_t, int); 87 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed, 88 char*, intptr_t, oop, intptr_t, int); 89 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit, 90 char*, intptr_t, oop, intptr_t, int); 91 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error, 92 char*, intptr_t, oop, intptr_t, int); 93 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end, 94 char*, intptr_t, oop, intptr_t, int); 95 96 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \ 97 { \ 98 char* data = NULL; \ 99 int len = 0; \ 100 Symbol* name = (clss)->name(); \ 101 if (name != NULL) { \ 102 data = (char*)name->bytes(); \ 103 len = name->utf8_length(); \ 104 } \ 105 HS_DTRACE_PROBE4(hotspot, class__initialization__##type, \ 106 data, len, (clss)->class_loader(), thread_type); \ 107 } 108 109 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \ 110 { \ 111 char* data = NULL; \ 112 int len = 0; \ 113 Symbol* name = (clss)->name(); \ 114 if (name != NULL) { \ 115 data = (char*)name->bytes(); \ 116 len = name->utf8_length(); \ 117 } \ 118 HS_DTRACE_PROBE5(hotspot, class__initialization__##type, \ 119 data, len, (clss)->class_loader(), thread_type, wait); \ 120 } 121 122 #else // ndef DTRACE_ENABLED 123 124 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) 125 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) 126 127 #endif // ndef DTRACE_ENABLED 128 129 bool instanceKlass::should_be_initialized() const { 130 return !is_initialized(); 131 } 132 133 klassVtable* instanceKlass::vtable() const { 134 return new klassVtable(as_klassOop(), start_of_vtable(), vtable_length() / vtableEntry::size()); 135 } 136 137 klassItable* instanceKlass::itable() const { 138 return new klassItable(as_klassOop()); 139 } 140 141 void instanceKlass::eager_initialize(Thread *thread) { 142 if (!EagerInitialization) return; 143 144 if (this->is_not_initialized()) { 145 // abort if the the class has a class initializer 146 if (this->class_initializer() != NULL) return; 147 148 // abort if it is java.lang.Object (initialization is handled in genesis) 149 klassOop super = this->super(); 150 if (super == NULL) return; 151 152 // abort if the super class should be initialized 153 if (!instanceKlass::cast(super)->is_initialized()) return; 154 155 // call body to expose the this pointer 156 instanceKlassHandle this_oop(thread, this->as_klassOop()); 157 eager_initialize_impl(this_oop); 158 } 159 } 160 161 162 void instanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) { 163 EXCEPTION_MARK; 164 ObjectLocker ol(this_oop, THREAD); 165 166 // abort if someone beat us to the initialization 167 if (!this_oop->is_not_initialized()) return; // note: not equivalent to is_initialized() 168 169 ClassState old_state = this_oop->_init_state; 170 link_class_impl(this_oop, true, THREAD); 171 if (HAS_PENDING_EXCEPTION) { 172 CLEAR_PENDING_EXCEPTION; 173 // Abort if linking the class throws an exception. 174 175 // Use a test to avoid redundantly resetting the state if there's 176 // no change. Set_init_state() asserts that state changes make 177 // progress, whereas here we might just be spinning in place. 178 if( old_state != this_oop->_init_state ) 179 this_oop->set_init_state (old_state); 180 } else { 181 // linking successfull, mark class as initialized 182 this_oop->set_init_state (fully_initialized); 183 // trace 184 if (TraceClassInitialization) { 185 ResourceMark rm(THREAD); 186 tty->print_cr("[Initialized %s without side effects]", this_oop->external_name()); 187 } 188 } 189 } 190 191 192 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 193 // process. The step comments refers to the procedure described in that section. 194 // Note: implementation moved to static method to expose the this pointer. 195 void instanceKlass::initialize(TRAPS) { 196 if (this->should_be_initialized()) { 197 HandleMark hm(THREAD); 198 instanceKlassHandle this_oop(THREAD, this->as_klassOop()); 199 initialize_impl(this_oop, CHECK); 200 // Note: at this point the class may be initialized 201 // OR it may be in the state of being initialized 202 // in case of recursive initialization! 203 } else { 204 assert(is_initialized(), "sanity check"); 205 } 206 } 207 208 209 bool instanceKlass::verify_code( 210 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) { 211 // 1) Verify the bytecodes 212 Verifier::Mode mode = 213 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 214 return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false); 215 } 216 217 218 // Used exclusively by the shared spaces dump mechanism to prevent 219 // classes mapped into the shared regions in new VMs from appearing linked. 220 221 void instanceKlass::unlink_class() { 222 assert(is_linked(), "must be linked"); 223 _init_state = loaded; 224 } 225 226 void instanceKlass::link_class(TRAPS) { 227 assert(is_loaded(), "must be loaded"); 228 if (!is_linked()) { 229 instanceKlassHandle this_oop(THREAD, this->as_klassOop()); 230 link_class_impl(this_oop, true, CHECK); 231 } 232 } 233 234 // Called to verify that a class can link during initialization, without 235 // throwing a VerifyError. 236 bool instanceKlass::link_class_or_fail(TRAPS) { 237 assert(is_loaded(), "must be loaded"); 238 if (!is_linked()) { 239 instanceKlassHandle this_oop(THREAD, this->as_klassOop()); 240 link_class_impl(this_oop, false, CHECK_false); 241 } 242 return is_linked(); 243 } 244 245 bool instanceKlass::link_class_impl( 246 instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) { 247 // check for error state 248 if (this_oop->is_in_error_state()) { 249 ResourceMark rm(THREAD); 250 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(), 251 this_oop->external_name(), false); 252 } 253 // return if already verified 254 if (this_oop->is_linked()) { 255 return true; 256 } 257 258 // Timing 259 // timer handles recursion 260 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 261 JavaThread* jt = (JavaThread*)THREAD; 262 263 // link super class before linking this class 264 instanceKlassHandle super(THREAD, this_oop->super()); 265 if (super.not_null()) { 266 if (super->is_interface()) { // check if super class is an interface 267 ResourceMark rm(THREAD); 268 Exceptions::fthrow( 269 THREAD_AND_LOCATION, 270 vmSymbols::java_lang_IncompatibleClassChangeError(), 271 "class %s has interface %s as super class", 272 this_oop->external_name(), 273 super->external_name() 274 ); 275 return false; 276 } 277 278 link_class_impl(super, throw_verifyerror, CHECK_false); 279 } 280 281 // link all interfaces implemented by this class before linking this class 282 objArrayHandle interfaces (THREAD, this_oop->local_interfaces()); 283 int num_interfaces = interfaces->length(); 284 for (int index = 0; index < num_interfaces; index++) { 285 HandleMark hm(THREAD); 286 instanceKlassHandle ih(THREAD, klassOop(interfaces->obj_at(index))); 287 link_class_impl(ih, throw_verifyerror, CHECK_false); 288 } 289 290 // in case the class is linked in the process of linking its superclasses 291 if (this_oop->is_linked()) { 292 return true; 293 } 294 295 // trace only the link time for this klass that includes 296 // the verification time 297 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 298 ClassLoader::perf_class_link_selftime(), 299 ClassLoader::perf_classes_linked(), 300 jt->get_thread_stat()->perf_recursion_counts_addr(), 301 jt->get_thread_stat()->perf_timers_addr(), 302 PerfClassTraceTime::CLASS_LINK); 303 304 // verification & rewriting 305 { 306 ObjectLocker ol(this_oop, THREAD); 307 // rewritten will have been set if loader constraint error found 308 // on an earlier link attempt 309 // don't verify or rewrite if already rewritten 310 if (!this_oop->is_linked()) { 311 if (!this_oop->is_rewritten()) { 312 { 313 // Timer includes any side effects of class verification (resolution, 314 // etc), but not recursive entry into verify_code(). 315 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(), 316 ClassLoader::perf_class_verify_selftime(), 317 ClassLoader::perf_classes_verified(), 318 jt->get_thread_stat()->perf_recursion_counts_addr(), 319 jt->get_thread_stat()->perf_timers_addr(), 320 PerfClassTraceTime::CLASS_VERIFY); 321 bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD); 322 if (!verify_ok) { 323 return false; 324 } 325 } 326 327 // Just in case a side-effect of verify linked this class already 328 // (which can sometimes happen since the verifier loads classes 329 // using custom class loaders, which are free to initialize things) 330 if (this_oop->is_linked()) { 331 return true; 332 } 333 334 // also sets rewritten 335 this_oop->rewrite_class(CHECK_false); 336 } 337 338 // relocate jsrs and link methods after they are all rewritten 339 this_oop->relocate_and_link_methods(CHECK_false); 340 341 // Initialize the vtable and interface table after 342 // methods have been rewritten since rewrite may 343 // fabricate new methodOops. 344 // also does loader constraint checking 345 if (!this_oop()->is_shared()) { 346 ResourceMark rm(THREAD); 347 this_oop->vtable()->initialize_vtable(true, CHECK_false); 348 this_oop->itable()->initialize_itable(true, CHECK_false); 349 } 350 #ifdef ASSERT 351 else { 352 ResourceMark rm(THREAD); 353 this_oop->vtable()->verify(tty, true); 354 // In case itable verification is ever added. 355 // this_oop->itable()->verify(tty, true); 356 } 357 #endif 358 this_oop->set_init_state(linked); 359 if (JvmtiExport::should_post_class_prepare()) { 360 Thread *thread = THREAD; 361 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 362 JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop()); 363 } 364 } 365 } 366 return true; 367 } 368 369 370 // Rewrite the byte codes of all of the methods of a class. 371 // The rewriter must be called exactly once. Rewriting must happen after 372 // verification but before the first method of the class is executed. 373 void instanceKlass::rewrite_class(TRAPS) { 374 assert(is_loaded(), "must be loaded"); 375 instanceKlassHandle this_oop(THREAD, this->as_klassOop()); 376 if (this_oop->is_rewritten()) { 377 assert(this_oop()->is_shared(), "rewriting an unshared class?"); 378 return; 379 } 380 Rewriter::rewrite(this_oop, CHECK); 381 this_oop->set_rewritten(); 382 } 383 384 // Now relocate and link method entry points after class is rewritten. 385 // This is outside is_rewritten flag. In case of an exception, it can be 386 // executed more than once. 387 void instanceKlass::relocate_and_link_methods(TRAPS) { 388 assert(is_loaded(), "must be loaded"); 389 instanceKlassHandle this_oop(THREAD, this->as_klassOop()); 390 Rewriter::relocate_and_link(this_oop, CHECK); 391 } 392 393 394 void instanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) { 395 // Make sure klass is linked (verified) before initialization 396 // A class could already be verified, since it has been reflected upon. 397 this_oop->link_class(CHECK); 398 399 DTRACE_CLASSINIT_PROBE(required, instanceKlass::cast(this_oop()), -1); 400 401 bool wait = false; 402 403 // refer to the JVM book page 47 for description of steps 404 // Step 1 405 { ObjectLocker ol(this_oop, THREAD); 406 407 Thread *self = THREAD; // it's passed the current thread 408 409 // Step 2 410 // If we were to use wait() instead of waitInterruptibly() then 411 // we might end up throwing IE from link/symbol resolution sites 412 // that aren't expected to throw. This would wreak havoc. See 6320309. 413 while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) { 414 wait = true; 415 ol.waitUninterruptibly(CHECK); 416 } 417 418 // Step 3 419 if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) { 420 DTRACE_CLASSINIT_PROBE_WAIT(recursive, instanceKlass::cast(this_oop()), -1,wait); 421 return; 422 } 423 424 // Step 4 425 if (this_oop->is_initialized()) { 426 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, instanceKlass::cast(this_oop()), -1,wait); 427 return; 428 } 429 430 // Step 5 431 if (this_oop->is_in_error_state()) { 432 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, instanceKlass::cast(this_oop()), -1,wait); 433 ResourceMark rm(THREAD); 434 const char* desc = "Could not initialize class "; 435 const char* className = this_oop->external_name(); 436 size_t msglen = strlen(desc) + strlen(className) + 1; 437 char* message = NEW_RESOURCE_ARRAY(char, msglen); 438 if (NULL == message) { 439 // Out of memory: can't create detailed error message 440 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 441 } else { 442 jio_snprintf(message, msglen, "%s%s", desc, className); 443 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 444 } 445 } 446 447 // Step 6 448 this_oop->set_init_state(being_initialized); 449 this_oop->set_init_thread(self); 450 } 451 452 // Step 7 453 klassOop super_klass = this_oop->super(); 454 if (super_klass != NULL && !this_oop->is_interface() && Klass::cast(super_klass)->should_be_initialized()) { 455 Klass::cast(super_klass)->initialize(THREAD); 456 457 if (HAS_PENDING_EXCEPTION) { 458 Handle e(THREAD, PENDING_EXCEPTION); 459 CLEAR_PENDING_EXCEPTION; 460 { 461 EXCEPTION_MARK; 462 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads 463 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below 464 } 465 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, instanceKlass::cast(this_oop()), -1,wait); 466 THROW_OOP(e()); 467 } 468 } 469 470 // Step 8 471 { 472 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 473 JavaThread* jt = (JavaThread*)THREAD; 474 DTRACE_CLASSINIT_PROBE_WAIT(clinit, instanceKlass::cast(this_oop()), -1,wait); 475 // Timer includes any side effects of class initialization (resolution, 476 // etc), but not recursive entry into call_class_initializer(). 477 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 478 ClassLoader::perf_class_init_selftime(), 479 ClassLoader::perf_classes_inited(), 480 jt->get_thread_stat()->perf_recursion_counts_addr(), 481 jt->get_thread_stat()->perf_timers_addr(), 482 PerfClassTraceTime::CLASS_CLINIT); 483 this_oop->call_class_initializer(THREAD); 484 } 485 486 // Step 9 487 if (!HAS_PENDING_EXCEPTION) { 488 this_oop->set_initialization_state_and_notify(fully_initialized, CHECK); 489 { ResourceMark rm(THREAD); 490 debug_only(this_oop->vtable()->verify(tty, true);) 491 } 492 } 493 else { 494 // Step 10 and 11 495 Handle e(THREAD, PENDING_EXCEPTION); 496 CLEAR_PENDING_EXCEPTION; 497 { 498 EXCEPTION_MARK; 499 this_oop->set_initialization_state_and_notify(initialization_error, THREAD); 500 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 501 } 502 DTRACE_CLASSINIT_PROBE_WAIT(error, instanceKlass::cast(this_oop()), -1,wait); 503 if (e->is_a(SystemDictionary::Error_klass())) { 504 THROW_OOP(e()); 505 } else { 506 JavaCallArguments args(e); 507 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 508 vmSymbols::throwable_void_signature(), 509 &args); 510 } 511 } 512 DTRACE_CLASSINIT_PROBE_WAIT(end, instanceKlass::cast(this_oop()), -1,wait); 513 } 514 515 516 // Note: implementation moved to static method to expose the this pointer. 517 void instanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 518 instanceKlassHandle kh(THREAD, this->as_klassOop()); 519 set_initialization_state_and_notify_impl(kh, state, CHECK); 520 } 521 522 void instanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) { 523 ObjectLocker ol(this_oop, THREAD); 524 this_oop->set_init_state(state); 525 ol.notify_all(CHECK); 526 } 527 528 void instanceKlass::add_implementor(klassOop k) { 529 assert(Compile_lock->owned_by_self(), ""); 530 // Filter out my subinterfaces. 531 // (Note: Interfaces are never on the subklass list.) 532 if (instanceKlass::cast(k)->is_interface()) return; 533 534 // Filter out subclasses whose supers already implement me. 535 // (Note: CHA must walk subclasses of direct implementors 536 // in order to locate indirect implementors.) 537 klassOop sk = instanceKlass::cast(k)->super(); 538 if (sk != NULL && instanceKlass::cast(sk)->implements_interface(as_klassOop())) 539 // We only need to check one immediate superclass, since the 540 // implements_interface query looks at transitive_interfaces. 541 // Any supers of the super have the same (or fewer) transitive_interfaces. 542 return; 543 544 // Update number of implementors 545 int i = _nof_implementors++; 546 547 // Record this implementor, if there are not too many already 548 if (i < implementors_limit) { 549 assert(_implementors[i] == NULL, "should be exactly one implementor"); 550 oop_store_without_check((oop*)&_implementors[i], k); 551 } else if (i == implementors_limit) { 552 // clear out the list on first overflow 553 for (int i2 = 0; i2 < implementors_limit; i2++) 554 oop_store_without_check((oop*)&_implementors[i2], NULL); 555 } 556 557 // The implementor also implements the transitive_interfaces 558 for (int index = 0; index < local_interfaces()->length(); index++) { 559 instanceKlass::cast(klassOop(local_interfaces()->obj_at(index)))->add_implementor(k); 560 } 561 } 562 563 void instanceKlass::init_implementor() { 564 for (int i = 0; i < implementors_limit; i++) 565 oop_store_without_check((oop*)&_implementors[i], NULL); 566 _nof_implementors = 0; 567 } 568 569 570 void instanceKlass::process_interfaces(Thread *thread) { 571 // link this class into the implementors list of every interface it implements 572 KlassHandle this_as_oop (thread, this->as_klassOop()); 573 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 574 assert(local_interfaces()->obj_at(i)->is_klass(), "must be a klass"); 575 instanceKlass* interf = instanceKlass::cast(klassOop(local_interfaces()->obj_at(i))); 576 assert(interf->is_interface(), "expected interface"); 577 interf->add_implementor(this_as_oop()); 578 } 579 } 580 581 bool instanceKlass::can_be_primary_super_slow() const { 582 if (is_interface()) 583 return false; 584 else 585 return Klass::can_be_primary_super_slow(); 586 } 587 588 objArrayOop instanceKlass::compute_secondary_supers(int num_extra_slots, TRAPS) { 589 // The secondaries are the implemented interfaces. 590 instanceKlass* ik = instanceKlass::cast(as_klassOop()); 591 objArrayHandle interfaces (THREAD, ik->transitive_interfaces()); 592 int num_secondaries = num_extra_slots + interfaces->length(); 593 if (num_secondaries == 0) { 594 return Universe::the_empty_system_obj_array(); 595 } else if (num_extra_slots == 0) { 596 return interfaces(); 597 } else { 598 // a mix of both 599 objArrayOop secondaries = oopFactory::new_system_objArray(num_secondaries, CHECK_NULL); 600 for (int i = 0; i < interfaces->length(); i++) { 601 secondaries->obj_at_put(num_extra_slots+i, interfaces->obj_at(i)); 602 } 603 return secondaries; 604 } 605 } 606 607 bool instanceKlass::compute_is_subtype_of(klassOop k) { 608 if (Klass::cast(k)->is_interface()) { 609 return implements_interface(k); 610 } else { 611 return Klass::compute_is_subtype_of(k); 612 } 613 } 614 615 bool instanceKlass::implements_interface(klassOop k) const { 616 if (as_klassOop() == k) return true; 617 assert(Klass::cast(k)->is_interface(), "should be an interface class"); 618 for (int i = 0; i < transitive_interfaces()->length(); i++) { 619 if (transitive_interfaces()->obj_at(i) == k) { 620 return true; 621 } 622 } 623 return false; 624 } 625 626 objArrayOop instanceKlass::allocate_objArray(int n, int length, TRAPS) { 627 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); 628 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 629 report_java_out_of_memory("Requested array size exceeds VM limit"); 630 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 631 } 632 int size = objArrayOopDesc::object_size(length); 633 klassOop ak = array_klass(n, CHECK_NULL); 634 KlassHandle h_ak (THREAD, ak); 635 objArrayOop o = 636 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL); 637 return o; 638 } 639 640 instanceOop instanceKlass::register_finalizer(instanceOop i, TRAPS) { 641 if (TraceFinalizerRegistration) { 642 tty->print("Registered "); 643 i->print_value_on(tty); 644 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i); 645 } 646 instanceHandle h_i(THREAD, i); 647 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 648 JavaValue result(T_VOID); 649 JavaCallArguments args(h_i); 650 methodHandle mh (THREAD, Universe::finalizer_register_method()); 651 JavaCalls::call(&result, mh, &args, CHECK_NULL); 652 return h_i(); 653 } 654 655 instanceOop instanceKlass::allocate_instance(TRAPS) { 656 assert(!oop_is_instanceMirror(), "wrong allocation path"); 657 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 658 int size = size_helper(); // Query before forming handle. 659 660 KlassHandle h_k(THREAD, as_klassOop()); 661 662 instanceOop i; 663 664 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL); 665 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 666 i = register_finalizer(i, CHECK_NULL); 667 } 668 return i; 669 } 670 671 instanceOop instanceKlass::allocate_permanent_instance(TRAPS) { 672 // Finalizer registration occurs in the Object.<init> constructor 673 // and constructors normally aren't run when allocating perm 674 // instances so simply disallow finalizable perm objects. This can 675 // be relaxed if a need for it is found. 676 assert(!has_finalizer(), "perm objects not allowed to have finalizers"); 677 assert(!oop_is_instanceMirror(), "wrong allocation path"); 678 int size = size_helper(); // Query before forming handle. 679 KlassHandle h_k(THREAD, as_klassOop()); 680 instanceOop i = (instanceOop) 681 CollectedHeap::permanent_obj_allocate(h_k, size, CHECK_NULL); 682 return i; 683 } 684 685 void instanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 686 if (is_interface() || is_abstract()) { 687 ResourceMark rm(THREAD); 688 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 689 : vmSymbols::java_lang_InstantiationException(), external_name()); 690 } 691 if (as_klassOop() == SystemDictionary::Class_klass()) { 692 ResourceMark rm(THREAD); 693 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 694 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 695 } 696 } 697 698 klassOop instanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 699 instanceKlassHandle this_oop(THREAD, as_klassOop()); 700 return array_klass_impl(this_oop, or_null, n, THREAD); 701 } 702 703 klassOop instanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) { 704 if (this_oop->array_klasses() == NULL) { 705 if (or_null) return NULL; 706 707 ResourceMark rm; 708 JavaThread *jt = (JavaThread *)THREAD; 709 { 710 // Atomic creation of array_klasses 711 MutexLocker mc(Compile_lock, THREAD); // for vtables 712 MutexLocker ma(MultiArray_lock, THREAD); 713 714 // Check if update has already taken place 715 if (this_oop->array_klasses() == NULL) { 716 objArrayKlassKlass* oakk = 717 (objArrayKlassKlass*)Universe::objArrayKlassKlassObj()->klass_part(); 718 719 klassOop k = oakk->allocate_objArray_klass(1, this_oop, CHECK_NULL); 720 this_oop->set_array_klasses(k); 721 } 722 } 723 } 724 // _this will always be set at this point 725 objArrayKlass* oak = (objArrayKlass*)this_oop->array_klasses()->klass_part(); 726 if (or_null) { 727 return oak->array_klass_or_null(n); 728 } 729 return oak->array_klass(n, CHECK_NULL); 730 } 731 732 klassOop instanceKlass::array_klass_impl(bool or_null, TRAPS) { 733 return array_klass_impl(or_null, 1, THREAD); 734 } 735 736 void instanceKlass::call_class_initializer(TRAPS) { 737 instanceKlassHandle ik (THREAD, as_klassOop()); 738 call_class_initializer_impl(ik, THREAD); 739 } 740 741 static int call_class_initializer_impl_counter = 0; // for debugging 742 743 methodOop instanceKlass::class_initializer() { 744 methodOop clinit = find_method( 745 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 746 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 747 return clinit; 748 } 749 return NULL; 750 } 751 752 void instanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) { 753 methodHandle h_method(THREAD, this_oop->class_initializer()); 754 assert(!this_oop->is_initialized(), "we cannot initialize twice"); 755 if (TraceClassInitialization) { 756 tty->print("%d Initializing ", call_class_initializer_impl_counter++); 757 this_oop->name()->print_value(); 758 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop()); 759 } 760 if (h_method() != NULL) { 761 JavaCallArguments args; // No arguments 762 JavaValue result(T_VOID); 763 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 764 } 765 } 766 767 768 void instanceKlass::mask_for(methodHandle method, int bci, 769 InterpreterOopMap* entry_for) { 770 // Dirty read, then double-check under a lock. 771 if (_oop_map_cache == NULL) { 772 // Otherwise, allocate a new one. 773 MutexLocker x(OopMapCacheAlloc_lock); 774 // First time use. Allocate a cache in C heap 775 if (_oop_map_cache == NULL) { 776 _oop_map_cache = new OopMapCache(); 777 } 778 } 779 // _oop_map_cache is constant after init; lookup below does is own locking. 780 _oop_map_cache->lookup(method, bci, entry_for); 781 } 782 783 784 bool instanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 785 const int n = fields()->length(); 786 for (int i = 0; i < n; i += next_offset ) { 787 int name_index = fields()->ushort_at(i + name_index_offset); 788 int sig_index = fields()->ushort_at(i + signature_index_offset); 789 Symbol* f_name = constants()->symbol_at(name_index); 790 Symbol* f_sig = constants()->symbol_at(sig_index); 791 if (f_name == name && f_sig == sig) { 792 fd->initialize(as_klassOop(), i); 793 return true; 794 } 795 } 796 return false; 797 } 798 799 800 void instanceKlass::shared_symbols_iterate(SymbolClosure* closure) { 801 Klass::shared_symbols_iterate(closure); 802 closure->do_symbol(&_generic_signature); 803 closure->do_symbol(&_source_file_name); 804 closure->do_symbol(&_source_debug_extension); 805 806 const int n = fields()->length(); 807 for (int i = 0; i < n; i += next_offset ) { 808 int name_index = fields()->ushort_at(i + name_index_offset); 809 closure->do_symbol(constants()->symbol_at_addr(name_index)); 810 int sig_index = fields()->ushort_at(i + signature_index_offset); 811 closure->do_symbol(constants()->symbol_at_addr(sig_index)); 812 } 813 } 814 815 816 klassOop instanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 817 const int n = local_interfaces()->length(); 818 for (int i = 0; i < n; i++) { 819 klassOop intf1 = klassOop(local_interfaces()->obj_at(i)); 820 assert(Klass::cast(intf1)->is_interface(), "just checking type"); 821 // search for field in current interface 822 if (instanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 823 assert(fd->is_static(), "interface field must be static"); 824 return intf1; 825 } 826 // search for field in direct superinterfaces 827 klassOop intf2 = instanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 828 if (intf2 != NULL) return intf2; 829 } 830 // otherwise field lookup fails 831 return NULL; 832 } 833 834 835 klassOop instanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 836 // search order according to newest JVM spec (5.4.3.2, p.167). 837 // 1) search for field in current klass 838 if (find_local_field(name, sig, fd)) { 839 return as_klassOop(); 840 } 841 // 2) search for field recursively in direct superinterfaces 842 { klassOop intf = find_interface_field(name, sig, fd); 843 if (intf != NULL) return intf; 844 } 845 // 3) apply field lookup recursively if superclass exists 846 { klassOop supr = super(); 847 if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, fd); 848 } 849 // 4) otherwise field lookup fails 850 return NULL; 851 } 852 853 854 klassOop instanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 855 // search order according to newest JVM spec (5.4.3.2, p.167). 856 // 1) search for field in current klass 857 if (find_local_field(name, sig, fd)) { 858 if (fd->is_static() == is_static) return as_klassOop(); 859 } 860 // 2) search for field recursively in direct superinterfaces 861 if (is_static) { 862 klassOop intf = find_interface_field(name, sig, fd); 863 if (intf != NULL) return intf; 864 } 865 // 3) apply field lookup recursively if superclass exists 866 { klassOop supr = super(); 867 if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 868 } 869 // 4) otherwise field lookup fails 870 return NULL; 871 } 872 873 874 bool instanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 875 int length = fields()->length(); 876 for (int i = 0; i < length; i += next_offset) { 877 if (offset_from_fields( i ) == offset) { 878 fd->initialize(as_klassOop(), i); 879 if (fd->is_static() == is_static) return true; 880 } 881 } 882 return false; 883 } 884 885 886 bool instanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 887 klassOop klass = as_klassOop(); 888 while (klass != NULL) { 889 if (instanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 890 return true; 891 } 892 klass = Klass::cast(klass)->super(); 893 } 894 return false; 895 } 896 897 898 void instanceKlass::methods_do(void f(methodOop method)) { 899 int len = methods()->length(); 900 for (int index = 0; index < len; index++) { 901 methodOop m = methodOop(methods()->obj_at(index)); 902 assert(m->is_method(), "must be method"); 903 f(m); 904 } 905 } 906 907 908 void instanceKlass::do_local_static_fields(FieldClosure* cl) { 909 fieldDescriptor fd; 910 int length = fields()->length(); 911 for (int i = 0; i < length; i += next_offset) { 912 fd.initialize(as_klassOop(), i); 913 if (fd.is_static()) cl->do_field(&fd); 914 } 915 } 916 917 918 void instanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) { 919 instanceKlassHandle h_this(THREAD, as_klassOop()); 920 do_local_static_fields_impl(h_this, f, CHECK); 921 } 922 923 924 void instanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) { 925 fieldDescriptor fd; 926 int length = this_oop->fields()->length(); 927 for (int i = 0; i < length; i += next_offset) { 928 fd.initialize(this_oop(), i); 929 if (fd.is_static()) { f(&fd, CHECK); } // Do NOT remove {}! (CHECK macro expands into several statements) 930 } 931 } 932 933 934 static int compare_fields_by_offset(int* a, int* b) { 935 return a[0] - b[0]; 936 } 937 938 void instanceKlass::do_nonstatic_fields(FieldClosure* cl) { 939 instanceKlass* super = superklass(); 940 if (super != NULL) { 941 super->do_nonstatic_fields(cl); 942 } 943 fieldDescriptor fd; 944 int length = fields()->length(); 945 // In DebugInfo nonstatic fields are sorted by offset. 946 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1)); 947 int j = 0; 948 for (int i = 0; i < length; i += next_offset) { 949 fd.initialize(as_klassOop(), i); 950 if (!fd.is_static()) { 951 fields_sorted[j + 0] = fd.offset(); 952 fields_sorted[j + 1] = i; 953 j += 2; 954 } 955 } 956 if (j > 0) { 957 length = j; 958 // _sort_Fn is defined in growableArray.hpp. 959 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 960 for (int i = 0; i < length; i += 2) { 961 fd.initialize(as_klassOop(), fields_sorted[i + 1]); 962 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 963 cl->do_field(&fd); 964 } 965 } 966 FREE_C_HEAP_ARRAY(int, fields_sorted); 967 } 968 969 970 void instanceKlass::array_klasses_do(void f(klassOop k)) { 971 if (array_klasses() != NULL) 972 arrayKlass::cast(array_klasses())->array_klasses_do(f); 973 } 974 975 976 void instanceKlass::with_array_klasses_do(void f(klassOop k)) { 977 f(as_klassOop()); 978 array_klasses_do(f); 979 } 980 981 #ifdef ASSERT 982 static int linear_search(objArrayOop methods, Symbol* name, Symbol* signature) { 983 int len = methods->length(); 984 for (int index = 0; index < len; index++) { 985 methodOop m = (methodOop)(methods->obj_at(index)); 986 assert(m->is_method(), "must be method"); 987 if (m->signature() == signature && m->name() == name) { 988 return index; 989 } 990 } 991 return -1; 992 } 993 #endif 994 995 methodOop instanceKlass::find_method(Symbol* name, Symbol* signature) const { 996 return instanceKlass::find_method(methods(), name, signature); 997 } 998 999 methodOop instanceKlass::find_method(objArrayOop methods, Symbol* name, Symbol* signature) { 1000 int len = methods->length(); 1001 // methods are sorted, so do binary search 1002 int l = 0; 1003 int h = len - 1; 1004 while (l <= h) { 1005 int mid = (l + h) >> 1; 1006 methodOop m = (methodOop)methods->obj_at(mid); 1007 assert(m->is_method(), "must be method"); 1008 int res = m->name()->fast_compare(name); 1009 if (res == 0) { 1010 // found matching name; do linear search to find matching signature 1011 // first, quick check for common case 1012 if (m->signature() == signature) return m; 1013 // search downwards through overloaded methods 1014 int i; 1015 for (i = mid - 1; i >= l; i--) { 1016 methodOop m = (methodOop)methods->obj_at(i); 1017 assert(m->is_method(), "must be method"); 1018 if (m->name() != name) break; 1019 if (m->signature() == signature) return m; 1020 } 1021 // search upwards 1022 for (i = mid + 1; i <= h; i++) { 1023 methodOop m = (methodOop)methods->obj_at(i); 1024 assert(m->is_method(), "must be method"); 1025 if (m->name() != name) break; 1026 if (m->signature() == signature) return m; 1027 } 1028 // not found 1029 #ifdef ASSERT 1030 int index = linear_search(methods, name, signature); 1031 assert(index == -1, err_msg("binary search should have found entry %d", index)); 1032 #endif 1033 return NULL; 1034 } else if (res < 0) { 1035 l = mid + 1; 1036 } else { 1037 h = mid - 1; 1038 } 1039 } 1040 #ifdef ASSERT 1041 int index = linear_search(methods, name, signature); 1042 assert(index == -1, err_msg("binary search should have found entry %d", index)); 1043 #endif 1044 return NULL; 1045 } 1046 1047 methodOop instanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature) const { 1048 klassOop klass = as_klassOop(); 1049 while (klass != NULL) { 1050 methodOop method = instanceKlass::cast(klass)->find_method(name, signature); 1051 if (method != NULL) return method; 1052 klass = instanceKlass::cast(klass)->super(); 1053 } 1054 return NULL; 1055 } 1056 1057 // lookup a method in all the interfaces that this class implements 1058 methodOop instanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1059 Symbol* signature) const { 1060 objArrayOop all_ifs = instanceKlass::cast(as_klassOop())->transitive_interfaces(); 1061 int num_ifs = all_ifs->length(); 1062 instanceKlass *ik = NULL; 1063 for (int i = 0; i < num_ifs; i++) { 1064 ik = instanceKlass::cast(klassOop(all_ifs->obj_at(i))); 1065 methodOop m = ik->lookup_method(name, signature); 1066 if (m != NULL) { 1067 return m; 1068 } 1069 } 1070 return NULL; 1071 } 1072 1073 /* jni_id_for_impl for jfieldIds only */ 1074 JNIid* instanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) { 1075 MutexLocker ml(JfieldIdCreation_lock); 1076 // Retry lookup after we got the lock 1077 JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset); 1078 if (probe == NULL) { 1079 // Slow case, allocate new static field identifier 1080 probe = new JNIid(this_oop->as_klassOop(), offset, this_oop->jni_ids()); 1081 this_oop->set_jni_ids(probe); 1082 } 1083 return probe; 1084 } 1085 1086 1087 /* jni_id_for for jfieldIds only */ 1088 JNIid* instanceKlass::jni_id_for(int offset) { 1089 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1090 if (probe == NULL) { 1091 probe = jni_id_for_impl(this->as_klassOop(), offset); 1092 } 1093 return probe; 1094 } 1095 1096 1097 // Lookup or create a jmethodID. 1098 // This code is called by the VMThread and JavaThreads so the 1099 // locking has to be done very carefully to avoid deadlocks 1100 // and/or other cache consistency problems. 1101 // 1102 jmethodID instanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) { 1103 size_t idnum = (size_t)method_h->method_idnum(); 1104 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1105 size_t length = 0; 1106 jmethodID id = NULL; 1107 1108 // We use a double-check locking idiom here because this cache is 1109 // performance sensitive. In the normal system, this cache only 1110 // transitions from NULL to non-NULL which is safe because we use 1111 // release_set_methods_jmethod_ids() to advertise the new cache. 1112 // A partially constructed cache should never be seen by a racing 1113 // thread. We also use release_store_ptr() to save a new jmethodID 1114 // in the cache so a partially constructed jmethodID should never be 1115 // seen either. Cache reads of existing jmethodIDs proceed without a 1116 // lock, but cache writes of a new jmethodID requires uniqueness and 1117 // creation of the cache itself requires no leaks so a lock is 1118 // generally acquired in those two cases. 1119 // 1120 // If the RedefineClasses() API has been used, then this cache can 1121 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1122 // Cache creation requires no leaks and we require safety between all 1123 // cache accesses and freeing of the old cache so a lock is generally 1124 // acquired when the RedefineClasses() API has been used. 1125 1126 if (jmeths != NULL) { 1127 // the cache already exists 1128 if (!ik_h->idnum_can_increment()) { 1129 // the cache can't grow so we can just get the current values 1130 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1131 } else { 1132 // cache can grow so we have to be more careful 1133 if (Threads::number_of_threads() == 0 || 1134 SafepointSynchronize::is_at_safepoint()) { 1135 // we're single threaded or at a safepoint - no locking needed 1136 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1137 } else { 1138 MutexLocker ml(JmethodIdCreation_lock); 1139 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1140 } 1141 } 1142 } 1143 // implied else: 1144 // we need to allocate a cache so default length and id values are good 1145 1146 if (jmeths == NULL || // no cache yet 1147 length <= idnum || // cache is too short 1148 id == NULL) { // cache doesn't contain entry 1149 1150 // This function can be called by the VMThread so we have to do all 1151 // things that might block on a safepoint before grabbing the lock. 1152 // Otherwise, we can deadlock with the VMThread or have a cache 1153 // consistency issue. These vars keep track of what we might have 1154 // to free after the lock is dropped. 1155 jmethodID to_dealloc_id = NULL; 1156 jmethodID* to_dealloc_jmeths = NULL; 1157 1158 // may not allocate new_jmeths or use it if we allocate it 1159 jmethodID* new_jmeths = NULL; 1160 if (length <= idnum) { 1161 // allocate a new cache that might be used 1162 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count()); 1163 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1); 1164 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1165 // cache size is stored in element[0], other elements offset by one 1166 new_jmeths[0] = (jmethodID)size; 1167 } 1168 1169 // allocate a new jmethodID that might be used 1170 jmethodID new_id = NULL; 1171 if (method_h->is_old() && !method_h->is_obsolete()) { 1172 // The method passed in is old (but not obsolete), we need to use the current version 1173 methodOop current_method = ik_h->method_with_idnum((int)idnum); 1174 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1175 methodHandle current_method_h(current_method == NULL? method_h() : current_method); 1176 new_id = JNIHandles::make_jmethod_id(current_method_h); 1177 } else { 1178 // It is the current version of the method or an obsolete method, 1179 // use the version passed in 1180 new_id = JNIHandles::make_jmethod_id(method_h); 1181 } 1182 1183 if (Threads::number_of_threads() == 0 || 1184 SafepointSynchronize::is_at_safepoint()) { 1185 // we're single threaded or at a safepoint - no locking needed 1186 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1187 &to_dealloc_id, &to_dealloc_jmeths); 1188 } else { 1189 MutexLocker ml(JmethodIdCreation_lock); 1190 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1191 &to_dealloc_id, &to_dealloc_jmeths); 1192 } 1193 1194 // The lock has been dropped so we can free resources. 1195 // Free up either the old cache or the new cache if we allocated one. 1196 if (to_dealloc_jmeths != NULL) { 1197 FreeHeap(to_dealloc_jmeths); 1198 } 1199 // free up the new ID since it wasn't needed 1200 if (to_dealloc_id != NULL) { 1201 JNIHandles::destroy_jmethod_id(to_dealloc_id); 1202 } 1203 } 1204 return id; 1205 } 1206 1207 1208 // Common code to fetch the jmethodID from the cache or update the 1209 // cache with the new jmethodID. This function should never do anything 1210 // that causes the caller to go to a safepoint or we can deadlock with 1211 // the VMThread or have cache consistency issues. 1212 // 1213 jmethodID instanceKlass::get_jmethod_id_fetch_or_update( 1214 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id, 1215 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1216 jmethodID** to_dealloc_jmeths_p) { 1217 assert(new_id != NULL, "sanity check"); 1218 assert(to_dealloc_id_p != NULL, "sanity check"); 1219 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 1220 assert(Threads::number_of_threads() == 0 || 1221 SafepointSynchronize::is_at_safepoint() || 1222 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 1223 1224 // reacquire the cache - we are locked, single threaded or at a safepoint 1225 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1226 jmethodID id = NULL; 1227 size_t length = 0; 1228 1229 if (jmeths == NULL || // no cache yet 1230 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 1231 if (jmeths != NULL) { 1232 // copy any existing entries from the old cache 1233 for (size_t index = 0; index < length; index++) { 1234 new_jmeths[index+1] = jmeths[index+1]; 1235 } 1236 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 1237 } 1238 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths); 1239 } else { 1240 // fetch jmethodID (if any) from the existing cache 1241 id = jmeths[idnum+1]; 1242 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 1243 } 1244 if (id == NULL) { 1245 // No matching jmethodID in the existing cache or we have a new 1246 // cache or we just grew the cache. This cache write is done here 1247 // by the first thread to win the foot race because a jmethodID 1248 // needs to be unique once it is generally available. 1249 id = new_id; 1250 1251 // The jmethodID cache can be read while unlocked so we have to 1252 // make sure the new jmethodID is complete before installing it 1253 // in the cache. 1254 OrderAccess::release_store_ptr(&jmeths[idnum+1], id); 1255 } else { 1256 *to_dealloc_id_p = new_id; // save new id for later delete 1257 } 1258 return id; 1259 } 1260 1261 1262 // Common code to get the jmethodID cache length and the jmethodID 1263 // value at index idnum if there is one. 1264 // 1265 void instanceKlass::get_jmethod_id_length_value(jmethodID* cache, 1266 size_t idnum, size_t *length_p, jmethodID* id_p) { 1267 assert(cache != NULL, "sanity check"); 1268 assert(length_p != NULL, "sanity check"); 1269 assert(id_p != NULL, "sanity check"); 1270 1271 // cache size is stored in element[0], other elements offset by one 1272 *length_p = (size_t)cache[0]; 1273 if (*length_p <= idnum) { // cache is too short 1274 *id_p = NULL; 1275 } else { 1276 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 1277 } 1278 } 1279 1280 1281 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 1282 jmethodID instanceKlass::jmethod_id_or_null(methodOop method) { 1283 size_t idnum = (size_t)method->method_idnum(); 1284 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1285 size_t length; // length assigned as debugging crumb 1286 jmethodID id = NULL; 1287 if (jmeths != NULL && // If there is a cache 1288 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 1289 id = jmeths[idnum+1]; // Look up the id (may be NULL) 1290 } 1291 return id; 1292 } 1293 1294 1295 // Cache an itable index 1296 void instanceKlass::set_cached_itable_index(size_t idnum, int index) { 1297 int* indices = methods_cached_itable_indices_acquire(); 1298 int* to_dealloc_indices = NULL; 1299 1300 // We use a double-check locking idiom here because this cache is 1301 // performance sensitive. In the normal system, this cache only 1302 // transitions from NULL to non-NULL which is safe because we use 1303 // release_set_methods_cached_itable_indices() to advertise the 1304 // new cache. A partially constructed cache should never be seen 1305 // by a racing thread. Cache reads and writes proceed without a 1306 // lock, but creation of the cache itself requires no leaks so a 1307 // lock is generally acquired in that case. 1308 // 1309 // If the RedefineClasses() API has been used, then this cache can 1310 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1311 // Cache creation requires no leaks and we require safety between all 1312 // cache accesses and freeing of the old cache so a lock is generally 1313 // acquired when the RedefineClasses() API has been used. 1314 1315 if (indices == NULL || idnum_can_increment()) { 1316 // we need a cache or the cache can grow 1317 MutexLocker ml(JNICachedItableIndex_lock); 1318 // reacquire the cache to see if another thread already did the work 1319 indices = methods_cached_itable_indices_acquire(); 1320 size_t length = 0; 1321 // cache size is stored in element[0], other elements offset by one 1322 if (indices == NULL || (length = (size_t)indices[0]) <= idnum) { 1323 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); 1324 int* new_indices = NEW_C_HEAP_ARRAY(int, size+1); 1325 new_indices[0] = (int)size; 1326 // copy any existing entries 1327 size_t i; 1328 for (i = 0; i < length; i++) { 1329 new_indices[i+1] = indices[i+1]; 1330 } 1331 // Set all the rest to -1 1332 for (i = length; i < size; i++) { 1333 new_indices[i+1] = -1; 1334 } 1335 if (indices != NULL) { 1336 // We have an old cache to delete so save it for after we 1337 // drop the lock. 1338 to_dealloc_indices = indices; 1339 } 1340 release_set_methods_cached_itable_indices(indices = new_indices); 1341 } 1342 1343 if (idnum_can_increment()) { 1344 // this cache can grow so we have to write to it safely 1345 indices[idnum+1] = index; 1346 } 1347 } else { 1348 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); 1349 } 1350 1351 if (!idnum_can_increment()) { 1352 // The cache cannot grow and this JNI itable index value does not 1353 // have to be unique like a jmethodID. If there is a race to set it, 1354 // it doesn't matter. 1355 indices[idnum+1] = index; 1356 } 1357 1358 if (to_dealloc_indices != NULL) { 1359 // we allocated a new cache so free the old one 1360 FreeHeap(to_dealloc_indices); 1361 } 1362 } 1363 1364 1365 // Retrieve a cached itable index 1366 int instanceKlass::cached_itable_index(size_t idnum) { 1367 int* indices = methods_cached_itable_indices_acquire(); 1368 if (indices != NULL && ((size_t)indices[0]) > idnum) { 1369 // indices exist and are long enough, retrieve possible cached 1370 return indices[idnum+1]; 1371 } 1372 return -1; 1373 } 1374 1375 1376 // 1377 // nmethodBucket is used to record dependent nmethods for 1378 // deoptimization. nmethod dependencies are actually <klass, method> 1379 // pairs but we really only care about the klass part for purposes of 1380 // finding nmethods which might need to be deoptimized. Instead of 1381 // recording the method, a count of how many times a particular nmethod 1382 // was recorded is kept. This ensures that any recording errors are 1383 // noticed since an nmethod should be removed as many times are it's 1384 // added. 1385 // 1386 class nmethodBucket { 1387 private: 1388 nmethod* _nmethod; 1389 int _count; 1390 nmethodBucket* _next; 1391 1392 public: 1393 nmethodBucket(nmethod* nmethod, nmethodBucket* next) { 1394 _nmethod = nmethod; 1395 _next = next; 1396 _count = 1; 1397 } 1398 int count() { return _count; } 1399 int increment() { _count += 1; return _count; } 1400 int decrement() { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; } 1401 nmethodBucket* next() { return _next; } 1402 void set_next(nmethodBucket* b) { _next = b; } 1403 nmethod* get_nmethod() { return _nmethod; } 1404 }; 1405 1406 1407 // 1408 // Walk the list of dependent nmethods searching for nmethods which 1409 // are dependent on the changes that were passed in and mark them for 1410 // deoptimization. Returns the number of nmethods found. 1411 // 1412 int instanceKlass::mark_dependent_nmethods(DepChange& changes) { 1413 assert_locked_or_safepoint(CodeCache_lock); 1414 int found = 0; 1415 nmethodBucket* b = _dependencies; 1416 while (b != NULL) { 1417 nmethod* nm = b->get_nmethod(); 1418 // since dependencies aren't removed until an nmethod becomes a zombie, 1419 // the dependency list may contain nmethods which aren't alive. 1420 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) { 1421 if (TraceDependencies) { 1422 ResourceMark rm; 1423 tty->print_cr("Marked for deoptimization"); 1424 tty->print_cr(" context = %s", this->external_name()); 1425 changes.print(); 1426 nm->print(); 1427 nm->print_dependencies(); 1428 } 1429 nm->mark_for_deoptimization(); 1430 found++; 1431 } 1432 b = b->next(); 1433 } 1434 return found; 1435 } 1436 1437 1438 // 1439 // Add an nmethodBucket to the list of dependencies for this nmethod. 1440 // It's possible that an nmethod has multiple dependencies on this klass 1441 // so a count is kept for each bucket to guarantee that creation and 1442 // deletion of dependencies is consistent. 1443 // 1444 void instanceKlass::add_dependent_nmethod(nmethod* nm) { 1445 assert_locked_or_safepoint(CodeCache_lock); 1446 nmethodBucket* b = _dependencies; 1447 nmethodBucket* last = NULL; 1448 while (b != NULL) { 1449 if (nm == b->get_nmethod()) { 1450 b->increment(); 1451 return; 1452 } 1453 b = b->next(); 1454 } 1455 _dependencies = new nmethodBucket(nm, _dependencies); 1456 } 1457 1458 1459 // 1460 // Decrement count of the nmethod in the dependency list and remove 1461 // the bucket competely when the count goes to 0. This method must 1462 // find a corresponding bucket otherwise there's a bug in the 1463 // recording of dependecies. 1464 // 1465 void instanceKlass::remove_dependent_nmethod(nmethod* nm) { 1466 assert_locked_or_safepoint(CodeCache_lock); 1467 nmethodBucket* b = _dependencies; 1468 nmethodBucket* last = NULL; 1469 while (b != NULL) { 1470 if (nm == b->get_nmethod()) { 1471 if (b->decrement() == 0) { 1472 if (last == NULL) { 1473 _dependencies = b->next(); 1474 } else { 1475 last->set_next(b->next()); 1476 } 1477 delete b; 1478 } 1479 return; 1480 } 1481 last = b; 1482 b = b->next(); 1483 } 1484 #ifdef ASSERT 1485 tty->print_cr("### %s can't find dependent nmethod:", this->external_name()); 1486 nm->print(); 1487 #endif // ASSERT 1488 ShouldNotReachHere(); 1489 } 1490 1491 1492 #ifndef PRODUCT 1493 void instanceKlass::print_dependent_nmethods(bool verbose) { 1494 nmethodBucket* b = _dependencies; 1495 int idx = 0; 1496 while (b != NULL) { 1497 nmethod* nm = b->get_nmethod(); 1498 tty->print("[%d] count=%d { ", idx++, b->count()); 1499 if (!verbose) { 1500 nm->print_on(tty, "nmethod"); 1501 tty->print_cr(" } "); 1502 } else { 1503 nm->print(); 1504 nm->print_dependencies(); 1505 tty->print_cr("--- } "); 1506 } 1507 b = b->next(); 1508 } 1509 } 1510 1511 1512 bool instanceKlass::is_dependent_nmethod(nmethod* nm) { 1513 nmethodBucket* b = _dependencies; 1514 while (b != NULL) { 1515 if (nm == b->get_nmethod()) { 1516 return true; 1517 } 1518 b = b->next(); 1519 } 1520 return false; 1521 } 1522 #endif //PRODUCT 1523 1524 1525 #ifdef ASSERT 1526 template <class T> void assert_is_in(T *p) { 1527 T heap_oop = oopDesc::load_heap_oop(p); 1528 if (!oopDesc::is_null(heap_oop)) { 1529 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 1530 assert(Universe::heap()->is_in(o), "should be in heap"); 1531 } 1532 } 1533 template <class T> void assert_is_in_closed_subset(T *p) { 1534 T heap_oop = oopDesc::load_heap_oop(p); 1535 if (!oopDesc::is_null(heap_oop)) { 1536 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 1537 assert(Universe::heap()->is_in_closed_subset(o), "should be in closed"); 1538 } 1539 } 1540 template <class T> void assert_is_in_reserved(T *p) { 1541 T heap_oop = oopDesc::load_heap_oop(p); 1542 if (!oopDesc::is_null(heap_oop)) { 1543 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 1544 assert(Universe::heap()->is_in_reserved(o), "should be in reserved"); 1545 } 1546 } 1547 template <class T> void assert_nothing(T *p) {} 1548 1549 #else 1550 template <class T> void assert_is_in(T *p) {} 1551 template <class T> void assert_is_in_closed_subset(T *p) {} 1552 template <class T> void assert_is_in_reserved(T *p) {} 1553 template <class T> void assert_nothing(T *p) {} 1554 #endif // ASSERT 1555 1556 // 1557 // Macros that iterate over areas of oops which are specialized on type of 1558 // oop pointer either narrow or wide, depending on UseCompressedOops 1559 // 1560 // Parameters are: 1561 // T - type of oop to point to (either oop or narrowOop) 1562 // start_p - starting pointer for region to iterate over 1563 // count - number of oops or narrowOops to iterate over 1564 // do_oop - action to perform on each oop (it's arbitrary C code which 1565 // makes it more efficient to put in a macro rather than making 1566 // it a template function) 1567 // assert_fn - assert function which is template function because performance 1568 // doesn't matter when enabled. 1569 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \ 1570 T, start_p, count, do_oop, \ 1571 assert_fn) \ 1572 { \ 1573 T* p = (T*)(start_p); \ 1574 T* const end = p + (count); \ 1575 while (p < end) { \ 1576 (assert_fn)(p); \ 1577 do_oop; \ 1578 ++p; \ 1579 } \ 1580 } 1581 1582 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \ 1583 T, start_p, count, do_oop, \ 1584 assert_fn) \ 1585 { \ 1586 T* const start = (T*)(start_p); \ 1587 T* p = start + (count); \ 1588 while (start < p) { \ 1589 --p; \ 1590 (assert_fn)(p); \ 1591 do_oop; \ 1592 } \ 1593 } 1594 1595 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \ 1596 T, start_p, count, low, high, \ 1597 do_oop, assert_fn) \ 1598 { \ 1599 T* const l = (T*)(low); \ 1600 T* const h = (T*)(high); \ 1601 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \ 1602 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \ 1603 "bounded region must be properly aligned"); \ 1604 T* p = (T*)(start_p); \ 1605 T* end = p + (count); \ 1606 if (p < l) p = l; \ 1607 if (end > h) end = h; \ 1608 while (p < end) { \ 1609 (assert_fn)(p); \ 1610 do_oop; \ 1611 ++p; \ 1612 } \ 1613 } 1614 1615 1616 // The following macros call specialized macros, passing either oop or 1617 // narrowOop as the specialization type. These test the UseCompressedOops 1618 // flag. 1619 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \ 1620 { \ 1621 /* Compute oopmap block range. The common case \ 1622 is nonstatic_oop_map_size == 1. */ \ 1623 OopMapBlock* map = start_of_nonstatic_oop_maps(); \ 1624 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \ 1625 if (UseCompressedOops) { \ 1626 while (map < end_map) { \ 1627 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \ 1628 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 1629 do_oop, assert_fn) \ 1630 ++map; \ 1631 } \ 1632 } else { \ 1633 while (map < end_map) { \ 1634 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \ 1635 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 1636 do_oop, assert_fn) \ 1637 ++map; \ 1638 } \ 1639 } \ 1640 } 1641 1642 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \ 1643 { \ 1644 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \ 1645 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \ 1646 if (UseCompressedOops) { \ 1647 while (start_map < map) { \ 1648 --map; \ 1649 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \ 1650 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 1651 do_oop, assert_fn) \ 1652 } \ 1653 } else { \ 1654 while (start_map < map) { \ 1655 --map; \ 1656 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \ 1657 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 1658 do_oop, assert_fn) \ 1659 } \ 1660 } \ 1661 } 1662 1663 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \ 1664 assert_fn) \ 1665 { \ 1666 /* Compute oopmap block range. The common case is \ 1667 nonstatic_oop_map_size == 1, so we accept the \ 1668 usually non-existent extra overhead of examining \ 1669 all the maps. */ \ 1670 OopMapBlock* map = start_of_nonstatic_oop_maps(); \ 1671 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \ 1672 if (UseCompressedOops) { \ 1673 while (map < end_map) { \ 1674 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \ 1675 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 1676 low, high, \ 1677 do_oop, assert_fn) \ 1678 ++map; \ 1679 } \ 1680 } else { \ 1681 while (map < end_map) { \ 1682 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \ 1683 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 1684 low, high, \ 1685 do_oop, assert_fn) \ 1686 ++map; \ 1687 } \ 1688 } \ 1689 } 1690 1691 void instanceKlass::oop_follow_contents(oop obj) { 1692 assert(obj != NULL, "can't follow the content of NULL object"); 1693 obj->follow_header(); 1694 InstanceKlass_OOP_MAP_ITERATE( \ 1695 obj, \ 1696 MarkSweep::mark_and_push(p), \ 1697 assert_is_in_closed_subset) 1698 } 1699 1700 #ifndef SERIALGC 1701 void instanceKlass::oop_follow_contents(ParCompactionManager* cm, 1702 oop obj) { 1703 assert(obj != NULL, "can't follow the content of NULL object"); 1704 obj->follow_header(cm); 1705 InstanceKlass_OOP_MAP_ITERATE( \ 1706 obj, \ 1707 PSParallelCompact::mark_and_push(cm, p), \ 1708 assert_is_in) 1709 } 1710 #endif // SERIALGC 1711 1712 // closure's do_header() method dicates whether the given closure should be 1713 // applied to the klass ptr in the object header. 1714 1715 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \ 1716 \ 1717 int instanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \ 1718 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\ 1719 /* header */ \ 1720 if (closure->do_header()) { \ 1721 obj->oop_iterate_header(closure); \ 1722 } \ 1723 InstanceKlass_OOP_MAP_ITERATE( \ 1724 obj, \ 1725 SpecializationStats:: \ 1726 record_do_oop_call##nv_suffix(SpecializationStats::ik); \ 1727 (closure)->do_oop##nv_suffix(p), \ 1728 assert_is_in_closed_subset) \ 1729 return size_helper(); \ 1730 } 1731 1732 #ifndef SERIALGC 1733 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \ 1734 \ 1735 int instanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \ 1736 OopClosureType* closure) { \ 1737 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \ 1738 /* header */ \ 1739 if (closure->do_header()) { \ 1740 obj->oop_iterate_header(closure); \ 1741 } \ 1742 /* instance variables */ \ 1743 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \ 1744 obj, \ 1745 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\ 1746 (closure)->do_oop##nv_suffix(p), \ 1747 assert_is_in_closed_subset) \ 1748 return size_helper(); \ 1749 } 1750 #endif // !SERIALGC 1751 1752 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \ 1753 \ 1754 int instanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \ 1755 OopClosureType* closure, \ 1756 MemRegion mr) { \ 1757 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\ 1758 if (closure->do_header()) { \ 1759 obj->oop_iterate_header(closure, mr); \ 1760 } \ 1761 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \ 1762 obj, mr.start(), mr.end(), \ 1763 (closure)->do_oop##nv_suffix(p), \ 1764 assert_is_in_closed_subset) \ 1765 return size_helper(); \ 1766 } 1767 1768 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN) 1769 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN) 1770 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m) 1771 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m) 1772 #ifndef SERIALGC 1773 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN) 1774 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN) 1775 #endif // !SERIALGC 1776 1777 int instanceKlass::oop_adjust_pointers(oop obj) { 1778 int size = size_helper(); 1779 InstanceKlass_OOP_MAP_ITERATE( \ 1780 obj, \ 1781 MarkSweep::adjust_pointer(p), \ 1782 assert_is_in) 1783 obj->adjust_header(); 1784 return size; 1785 } 1786 1787 #ifndef SERIALGC 1788 void instanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) { 1789 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \ 1790 obj, \ 1791 if (PSScavenge::should_scavenge(p)) { \ 1792 pm->claim_or_forward_depth(p); \ 1793 }, \ 1794 assert_nothing ) 1795 } 1796 1797 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) { 1798 InstanceKlass_OOP_MAP_ITERATE( \ 1799 obj, \ 1800 PSParallelCompact::adjust_pointer(p), \ 1801 assert_nothing) 1802 return size_helper(); 1803 } 1804 1805 #endif // SERIALGC 1806 1807 // This klass is alive but the implementor link is not followed/updated. 1808 // Subklass and sibling links are handled by Klass::follow_weak_klass_links 1809 1810 void instanceKlass::follow_weak_klass_links( 1811 BoolObjectClosure* is_alive, OopClosure* keep_alive) { 1812 assert(is_alive->do_object_b(as_klassOop()), "this oop should be live"); 1813 if (ClassUnloading) { 1814 for (int i = 0; i < implementors_limit; i++) { 1815 klassOop impl = _implementors[i]; 1816 if (impl == NULL) break; // no more in the list 1817 if (!is_alive->do_object_b(impl)) { 1818 // remove this guy from the list by overwriting him with the tail 1819 int lasti = --_nof_implementors; 1820 assert(lasti >= i && lasti < implementors_limit, "just checking"); 1821 _implementors[i] = _implementors[lasti]; 1822 _implementors[lasti] = NULL; 1823 --i; // rerun the loop at this index 1824 } 1825 } 1826 } else { 1827 for (int i = 0; i < implementors_limit; i++) { 1828 keep_alive->do_oop(&adr_implementors()[i]); 1829 } 1830 } 1831 Klass::follow_weak_klass_links(is_alive, keep_alive); 1832 } 1833 1834 void instanceKlass::remove_unshareable_info() { 1835 Klass::remove_unshareable_info(); 1836 init_implementor(); 1837 } 1838 1839 static void clear_all_breakpoints(methodOop m) { 1840 m->clear_all_breakpoints(); 1841 } 1842 1843 void instanceKlass::release_C_heap_structures() { 1844 // Deallocate oop map cache 1845 if (_oop_map_cache != NULL) { 1846 delete _oop_map_cache; 1847 _oop_map_cache = NULL; 1848 } 1849 1850 // Deallocate JNI identifiers for jfieldIDs 1851 JNIid::deallocate(jni_ids()); 1852 set_jni_ids(NULL); 1853 1854 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1855 if (jmeths != (jmethodID*)NULL) { 1856 release_set_methods_jmethod_ids(NULL); 1857 FreeHeap(jmeths); 1858 } 1859 1860 int* indices = methods_cached_itable_indices_acquire(); 1861 if (indices != (int*)NULL) { 1862 release_set_methods_cached_itable_indices(NULL); 1863 FreeHeap(indices); 1864 } 1865 1866 // release dependencies 1867 nmethodBucket* b = _dependencies; 1868 _dependencies = NULL; 1869 while (b != NULL) { 1870 nmethodBucket* next = b->next(); 1871 delete b; 1872 b = next; 1873 } 1874 1875 // Deallocate breakpoint records 1876 if (breakpoints() != 0x0) { 1877 methods_do(clear_all_breakpoints); 1878 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 1879 } 1880 1881 // deallocate information about previous versions 1882 if (_previous_versions != NULL) { 1883 for (int i = _previous_versions->length() - 1; i >= 0; i--) { 1884 PreviousVersionNode * pv_node = _previous_versions->at(i); 1885 delete pv_node; 1886 } 1887 delete _previous_versions; 1888 _previous_versions = NULL; 1889 } 1890 1891 // deallocate the cached class file 1892 if (_cached_class_file_bytes != NULL) { 1893 os::free(_cached_class_file_bytes); 1894 _cached_class_file_bytes = NULL; 1895 _cached_class_file_len = 0; 1896 } 1897 1898 // Decrement symbol reference counts associated with the unloaded class. 1899 if (_name != NULL) _name->decrement_refcount(); 1900 // unreference array name derived from this class name (arrays of an unloaded 1901 // class can't be referenced anymore). 1902 if (_array_name != NULL) _array_name->decrement_refcount(); 1903 if (_source_file_name != NULL) _source_file_name->decrement_refcount(); 1904 if (_source_debug_extension != NULL) _source_debug_extension->decrement_refcount(); 1905 // walk constant pool and decrement symbol reference counts 1906 _constants->unreference_symbols(); 1907 } 1908 1909 void instanceKlass::set_source_file_name(Symbol* n) { 1910 _source_file_name = n; 1911 if (_source_file_name != NULL) _source_file_name->increment_refcount(); 1912 } 1913 1914 void instanceKlass::set_source_debug_extension(Symbol* n) { 1915 _source_debug_extension = n; 1916 if (_source_debug_extension != NULL) _source_debug_extension->increment_refcount(); 1917 } 1918 1919 address instanceKlass::static_field_addr(int offset) { 1920 return (address)(offset + instanceMirrorKlass::offset_of_static_fields() + (intptr_t)java_mirror()); 1921 } 1922 1923 1924 const char* instanceKlass::signature_name() const { 1925 const char* src = (const char*) (name()->as_C_string()); 1926 const int src_length = (int)strlen(src); 1927 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3); 1928 int src_index = 0; 1929 int dest_index = 0; 1930 dest[dest_index++] = 'L'; 1931 while (src_index < src_length) { 1932 dest[dest_index++] = src[src_index++]; 1933 } 1934 dest[dest_index++] = ';'; 1935 dest[dest_index] = '\0'; 1936 return dest; 1937 } 1938 1939 // different verisons of is_same_class_package 1940 bool instanceKlass::is_same_class_package(klassOop class2) { 1941 klassOop class1 = as_klassOop(); 1942 oop classloader1 = instanceKlass::cast(class1)->class_loader(); 1943 Symbol* classname1 = Klass::cast(class1)->name(); 1944 1945 if (Klass::cast(class2)->oop_is_objArray()) { 1946 class2 = objArrayKlass::cast(class2)->bottom_klass(); 1947 } 1948 oop classloader2; 1949 if (Klass::cast(class2)->oop_is_instance()) { 1950 classloader2 = instanceKlass::cast(class2)->class_loader(); 1951 } else { 1952 assert(Klass::cast(class2)->oop_is_typeArray(), "should be type array"); 1953 classloader2 = NULL; 1954 } 1955 Symbol* classname2 = Klass::cast(class2)->name(); 1956 1957 return instanceKlass::is_same_class_package(classloader1, classname1, 1958 classloader2, classname2); 1959 } 1960 1961 bool instanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) { 1962 klassOop class1 = as_klassOop(); 1963 oop classloader1 = instanceKlass::cast(class1)->class_loader(); 1964 Symbol* classname1 = Klass::cast(class1)->name(); 1965 1966 return instanceKlass::is_same_class_package(classloader1, classname1, 1967 classloader2, classname2); 1968 } 1969 1970 // return true if two classes are in the same package, classloader 1971 // and classname information is enough to determine a class's package 1972 bool instanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1, 1973 oop class_loader2, Symbol* class_name2) { 1974 if (class_loader1 != class_loader2) { 1975 return false; 1976 } else if (class_name1 == class_name2) { 1977 return true; // skip painful bytewise comparison 1978 } else { 1979 ResourceMark rm; 1980 1981 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly 1982 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding. 1983 // Otherwise, we just compare jbyte values between the strings. 1984 const jbyte *name1 = class_name1->base(); 1985 const jbyte *name2 = class_name2->base(); 1986 1987 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/'); 1988 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/'); 1989 1990 if ((last_slash1 == NULL) || (last_slash2 == NULL)) { 1991 // One of the two doesn't have a package. Only return true 1992 // if the other one also doesn't have a package. 1993 return last_slash1 == last_slash2; 1994 } else { 1995 // Skip over '['s 1996 if (*name1 == '[') { 1997 do { 1998 name1++; 1999 } while (*name1 == '['); 2000 if (*name1 != 'L') { 2001 // Something is terribly wrong. Shouldn't be here. 2002 return false; 2003 } 2004 } 2005 if (*name2 == '[') { 2006 do { 2007 name2++; 2008 } while (*name2 == '['); 2009 if (*name2 != 'L') { 2010 // Something is terribly wrong. Shouldn't be here. 2011 return false; 2012 } 2013 } 2014 2015 // Check that package part is identical 2016 int length1 = last_slash1 - name1; 2017 int length2 = last_slash2 - name2; 2018 2019 return UTF8::equal(name1, length1, name2, length2); 2020 } 2021 } 2022 } 2023 2024 // Returns true iff super_method can be overridden by a method in targetclassname 2025 // See JSL 3rd edition 8.4.6.1 2026 // Assumes name-signature match 2027 // "this" is instanceKlass of super_method which must exist 2028 // note that the instanceKlass of the method in the targetclassname has not always been created yet 2029 bool instanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2030 // Private methods can not be overridden 2031 if (super_method->is_private()) { 2032 return false; 2033 } 2034 // If super method is accessible, then override 2035 if ((super_method->is_protected()) || 2036 (super_method->is_public())) { 2037 return true; 2038 } 2039 // Package-private methods are not inherited outside of package 2040 assert(super_method->is_package_private(), "must be package private"); 2041 return(is_same_class_package(targetclassloader(), targetclassname)); 2042 } 2043 2044 /* defined for now in jvm.cpp, for historical reasons *-- 2045 klassOop instanceKlass::compute_enclosing_class_impl(instanceKlassHandle self, 2046 Symbol*& simple_name_result, TRAPS) { 2047 ... 2048 } 2049 */ 2050 2051 // tell if two classes have the same enclosing class (at package level) 2052 bool instanceKlass::is_same_package_member_impl(instanceKlassHandle class1, 2053 klassOop class2_oop, TRAPS) { 2054 if (class2_oop == class1->as_klassOop()) return true; 2055 if (!Klass::cast(class2_oop)->oop_is_instance()) return false; 2056 instanceKlassHandle class2(THREAD, class2_oop); 2057 2058 // must be in same package before we try anything else 2059 if (!class1->is_same_class_package(class2->class_loader(), class2->name())) 2060 return false; 2061 2062 // As long as there is an outer1.getEnclosingClass, 2063 // shift the search outward. 2064 instanceKlassHandle outer1 = class1; 2065 for (;;) { 2066 // As we walk along, look for equalities between outer1 and class2. 2067 // Eventually, the walks will terminate as outer1 stops 2068 // at the top-level class around the original class. 2069 bool ignore_inner_is_member; 2070 klassOop next = outer1->compute_enclosing_class(&ignore_inner_is_member, 2071 CHECK_false); 2072 if (next == NULL) break; 2073 if (next == class2()) return true; 2074 outer1 = instanceKlassHandle(THREAD, next); 2075 } 2076 2077 // Now do the same for class2. 2078 instanceKlassHandle outer2 = class2; 2079 for (;;) { 2080 bool ignore_inner_is_member; 2081 klassOop next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2082 CHECK_false); 2083 if (next == NULL) break; 2084 // Might as well check the new outer against all available values. 2085 if (next == class1()) return true; 2086 if (next == outer1()) return true; 2087 outer2 = instanceKlassHandle(THREAD, next); 2088 } 2089 2090 // If by this point we have not found an equality between the 2091 // two classes, we know they are in separate package members. 2092 return false; 2093 } 2094 2095 2096 jint instanceKlass::compute_modifier_flags(TRAPS) const { 2097 klassOop k = as_klassOop(); 2098 jint access = access_flags().as_int(); 2099 2100 // But check if it happens to be member class. 2101 typeArrayOop inner_class_list = inner_classes(); 2102 int length = (inner_class_list == NULL) ? 0 : inner_class_list->length(); 2103 assert (length % instanceKlass::inner_class_next_offset == 0, "just checking"); 2104 if (length > 0) { 2105 typeArrayHandle inner_class_list_h(THREAD, inner_class_list); 2106 instanceKlassHandle ik(THREAD, k); 2107 for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) { 2108 int ioff = inner_class_list_h->ushort_at( 2109 i + instanceKlass::inner_class_inner_class_info_offset); 2110 2111 // Inner class attribute can be zero, skip it. 2112 // Strange but true: JVM spec. allows null inner class refs. 2113 if (ioff == 0) continue; 2114 2115 // only look at classes that are already loaded 2116 // since we are looking for the flags for our self. 2117 Symbol* inner_name = ik->constants()->klass_name_at(ioff); 2118 if ((ik->name() == inner_name)) { 2119 // This is really a member class. 2120 access = inner_class_list_h->ushort_at(i + instanceKlass::inner_class_access_flags_offset); 2121 break; 2122 } 2123 } 2124 } 2125 // Remember to strip ACC_SUPER bit 2126 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2127 } 2128 2129 jint instanceKlass::jvmti_class_status() const { 2130 jint result = 0; 2131 2132 if (is_linked()) { 2133 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2134 } 2135 2136 if (is_initialized()) { 2137 assert(is_linked(), "Class status is not consistent"); 2138 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2139 } 2140 if (is_in_error_state()) { 2141 result |= JVMTI_CLASS_STATUS_ERROR; 2142 } 2143 return result; 2144 } 2145 2146 methodOop instanceKlass::method_at_itable(klassOop holder, int index, TRAPS) { 2147 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2148 int method_table_offset_in_words = ioe->offset()/wordSize; 2149 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2150 / itableOffsetEntry::size(); 2151 2152 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2153 // If the interface isn't implemented by the receiver class, 2154 // the VM should throw IncompatibleClassChangeError. 2155 if (cnt >= nof_interfaces) { 2156 THROW_0(vmSymbols::java_lang_IncompatibleClassChangeError()); 2157 } 2158 2159 klassOop ik = ioe->interface_klass(); 2160 if (ik == holder) break; 2161 } 2162 2163 itableMethodEntry* ime = ioe->first_method_entry(as_klassOop()); 2164 methodOop m = ime[index].method(); 2165 if (m == NULL) { 2166 THROW_0(vmSymbols::java_lang_AbstractMethodError()); 2167 } 2168 return m; 2169 } 2170 2171 // On-stack replacement stuff 2172 void instanceKlass::add_osr_nmethod(nmethod* n) { 2173 // only one compilation can be active 2174 NEEDS_CLEANUP 2175 // This is a short non-blocking critical region, so the no safepoint check is ok. 2176 OsrList_lock->lock_without_safepoint_check(); 2177 assert(n->is_osr_method(), "wrong kind of nmethod"); 2178 n->set_osr_link(osr_nmethods_head()); 2179 set_osr_nmethods_head(n); 2180 // Raise the highest osr level if necessary 2181 if (TieredCompilation) { 2182 methodOop m = n->method(); 2183 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2184 } 2185 // Remember to unlock again 2186 OsrList_lock->unlock(); 2187 2188 // Get rid of the osr methods for the same bci that have lower levels. 2189 if (TieredCompilation) { 2190 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2191 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2192 if (inv != NULL && inv->is_in_use()) { 2193 inv->make_not_entrant(); 2194 } 2195 } 2196 } 2197 } 2198 2199 2200 void instanceKlass::remove_osr_nmethod(nmethod* n) { 2201 // This is a short non-blocking critical region, so the no safepoint check is ok. 2202 OsrList_lock->lock_without_safepoint_check(); 2203 assert(n->is_osr_method(), "wrong kind of nmethod"); 2204 nmethod* last = NULL; 2205 nmethod* cur = osr_nmethods_head(); 2206 int max_level = CompLevel_none; // Find the max comp level excluding n 2207 methodOop m = n->method(); 2208 // Search for match 2209 while(cur != NULL && cur != n) { 2210 if (TieredCompilation) { 2211 // Find max level before n 2212 max_level = MAX2(max_level, cur->comp_level()); 2213 } 2214 last = cur; 2215 cur = cur->osr_link(); 2216 } 2217 nmethod* next = NULL; 2218 if (cur == n) { 2219 next = cur->osr_link(); 2220 if (last == NULL) { 2221 // Remove first element 2222 set_osr_nmethods_head(next); 2223 } else { 2224 last->set_osr_link(next); 2225 } 2226 } 2227 n->set_osr_link(NULL); 2228 if (TieredCompilation) { 2229 cur = next; 2230 while (cur != NULL) { 2231 // Find max level after n 2232 max_level = MAX2(max_level, cur->comp_level()); 2233 cur = cur->osr_link(); 2234 } 2235 m->set_highest_osr_comp_level(max_level); 2236 } 2237 // Remember to unlock again 2238 OsrList_lock->unlock(); 2239 } 2240 2241 nmethod* instanceKlass::lookup_osr_nmethod(const methodOop m, int bci, int comp_level, bool match_level) const { 2242 // This is a short non-blocking critical region, so the no safepoint check is ok. 2243 OsrList_lock->lock_without_safepoint_check(); 2244 nmethod* osr = osr_nmethods_head(); 2245 nmethod* best = NULL; 2246 while (osr != NULL) { 2247 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2248 // There can be a time when a c1 osr method exists but we are waiting 2249 // for a c2 version. When c2 completes its osr nmethod we will trash 2250 // the c1 version and only be able to find the c2 version. However 2251 // while we overflow in the c1 code at back branches we don't want to 2252 // try and switch to the same code as we are already running 2253 2254 if (osr->method() == m && 2255 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 2256 if (match_level) { 2257 if (osr->comp_level() == comp_level) { 2258 // Found a match - return it. 2259 OsrList_lock->unlock(); 2260 return osr; 2261 } 2262 } else { 2263 if (best == NULL || (osr->comp_level() > best->comp_level())) { 2264 if (osr->comp_level() == CompLevel_highest_tier) { 2265 // Found the best possible - return it. 2266 OsrList_lock->unlock(); 2267 return osr; 2268 } 2269 best = osr; 2270 } 2271 } 2272 } 2273 osr = osr->osr_link(); 2274 } 2275 OsrList_lock->unlock(); 2276 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 2277 return best; 2278 } 2279 return NULL; 2280 } 2281 2282 // ----------------------------------------------------------------------------------------------------- 2283 #ifndef PRODUCT 2284 2285 // Printing 2286 2287 #define BULLET " - " 2288 2289 void FieldPrinter::do_field(fieldDescriptor* fd) { 2290 _st->print(BULLET); 2291 if (_obj == NULL) { 2292 fd->print_on(_st); 2293 _st->cr(); 2294 } else { 2295 fd->print_on_for(_st, _obj); 2296 _st->cr(); 2297 } 2298 } 2299 2300 2301 void instanceKlass::oop_print_on(oop obj, outputStream* st) { 2302 Klass::oop_print_on(obj, st); 2303 2304 if (as_klassOop() == SystemDictionary::String_klass()) { 2305 typeArrayOop value = java_lang_String::value(obj); 2306 juint offset = java_lang_String::offset(obj); 2307 juint length = java_lang_String::length(obj); 2308 if (value != NULL && 2309 value->is_typeArray() && 2310 offset <= (juint) value->length() && 2311 offset + length <= (juint) value->length()) { 2312 st->print(BULLET"string: "); 2313 Handle h_obj(obj); 2314 java_lang_String::print(h_obj, st); 2315 st->cr(); 2316 if (!WizardMode) return; // that is enough 2317 } 2318 } 2319 2320 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 2321 FieldPrinter print_field(st, obj); 2322 do_nonstatic_fields(&print_field); 2323 2324 if (as_klassOop() == SystemDictionary::Class_klass()) { 2325 st->print(BULLET"signature: "); 2326 java_lang_Class::print_signature(obj, st); 2327 st->cr(); 2328 klassOop mirrored_klass = java_lang_Class::as_klassOop(obj); 2329 st->print(BULLET"fake entry for mirror: "); 2330 mirrored_klass->print_value_on(st); 2331 st->cr(); 2332 st->print(BULLET"fake entry resolved_constructor: "); 2333 methodOop ctor = java_lang_Class::resolved_constructor(obj); 2334 ctor->print_value_on(st); 2335 klassOop array_klass = java_lang_Class::array_klass(obj); 2336 st->cr(); 2337 st->print(BULLET"fake entry for array: "); 2338 array_klass->print_value_on(st); 2339 st->cr(); 2340 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 2341 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 2342 klassOop real_klass = java_lang_Class::as_klassOop(obj); 2343 if (real_klass != NULL && real_klass->klass_part()->oop_is_instance()) { 2344 instanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 2345 } 2346 } else if (as_klassOop() == SystemDictionary::MethodType_klass()) { 2347 st->print(BULLET"signature: "); 2348 java_lang_invoke_MethodType::print_signature(obj, st); 2349 st->cr(); 2350 } 2351 } 2352 2353 #endif //PRODUCT 2354 2355 void instanceKlass::oop_print_value_on(oop obj, outputStream* st) { 2356 st->print("a "); 2357 name()->print_value_on(st); 2358 obj->print_address_on(st); 2359 if (as_klassOop() == SystemDictionary::String_klass() 2360 && java_lang_String::value(obj) != NULL) { 2361 ResourceMark rm; 2362 int len = java_lang_String::length(obj); 2363 int plen = (len < 24 ? len : 12); 2364 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 2365 st->print(" = \"%s\"", str); 2366 if (len > plen) 2367 st->print("...[%d]", len); 2368 } else if (as_klassOop() == SystemDictionary::Class_klass()) { 2369 klassOop k = java_lang_Class::as_klassOop(obj); 2370 st->print(" = "); 2371 if (k != NULL) { 2372 k->print_value_on(st); 2373 } else { 2374 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 2375 st->print("%s", tname ? tname : "type?"); 2376 } 2377 } else if (as_klassOop() == SystemDictionary::MethodType_klass()) { 2378 st->print(" = "); 2379 java_lang_invoke_MethodType::print_signature(obj, st); 2380 } else if (java_lang_boxing_object::is_instance(obj)) { 2381 st->print(" = "); 2382 java_lang_boxing_object::print(obj, st); 2383 } 2384 } 2385 2386 const char* instanceKlass::internal_name() const { 2387 return external_name(); 2388 } 2389 2390 // Verification 2391 2392 class VerifyFieldClosure: public OopClosure { 2393 protected: 2394 template <class T> void do_oop_work(T* p) { 2395 guarantee(Universe::heap()->is_in_closed_subset(p), "should be in heap"); 2396 oop obj = oopDesc::load_decode_heap_oop(p); 2397 if (!obj->is_oop_or_null()) { 2398 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj); 2399 Universe::print(); 2400 guarantee(false, "boom"); 2401 } 2402 } 2403 public: 2404 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 2405 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 2406 }; 2407 2408 void instanceKlass::oop_verify_on(oop obj, outputStream* st) { 2409 Klass::oop_verify_on(obj, st); 2410 VerifyFieldClosure blk; 2411 oop_oop_iterate(obj, &blk); 2412 } 2413 2414 #ifndef PRODUCT 2415 2416 void instanceKlass::verify_class_klass_nonstatic_oop_maps(klassOop k) { 2417 // This verification code is disabled. JDK_Version::is_gte_jdk14x_version() 2418 // cannot be called since this function is called before the VM is 2419 // able to determine what JDK version is running with. 2420 // The check below always is false since 1.4. 2421 return; 2422 2423 // This verification code temporarily disabled for the 1.4 2424 // reflection implementation since java.lang.Class now has 2425 // Java-level instance fields. Should rewrite this to handle this 2426 // case. 2427 if (!(JDK_Version::is_gte_jdk14x_version() && UseNewReflection)) { 2428 // Verify that java.lang.Class instances have a fake oop field added. 2429 instanceKlass* ik = instanceKlass::cast(k); 2430 2431 // Check that we have the right class 2432 static bool first_time = true; 2433 guarantee(k == SystemDictionary::Class_klass() && first_time, "Invalid verify of maps"); 2434 first_time = false; 2435 const int extra = java_lang_Class::number_of_fake_oop_fields; 2436 guarantee(ik->nonstatic_field_size() == extra, "just checking"); 2437 guarantee(ik->nonstatic_oop_map_count() == 1, "just checking"); 2438 guarantee(ik->size_helper() == align_object_size(instanceOopDesc::header_size() + extra), "just checking"); 2439 2440 // Check that the map is (2,extra) 2441 int offset = java_lang_Class::klass_offset; 2442 2443 OopMapBlock* map = ik->start_of_nonstatic_oop_maps(); 2444 guarantee(map->offset() == offset && map->count() == (unsigned int) extra, 2445 "sanity"); 2446 } 2447 } 2448 2449 #endif // ndef PRODUCT 2450 2451 // JNIid class for jfieldIDs only 2452 // Note to reviewers: 2453 // These JNI functions are just moved over to column 1 and not changed 2454 // in the compressed oops workspace. 2455 JNIid::JNIid(klassOop holder, int offset, JNIid* next) { 2456 _holder = holder; 2457 _offset = offset; 2458 _next = next; 2459 debug_only(_is_static_field_id = false;) 2460 } 2461 2462 2463 JNIid* JNIid::find(int offset) { 2464 JNIid* current = this; 2465 while (current != NULL) { 2466 if (current->offset() == offset) return current; 2467 current = current->next(); 2468 } 2469 return NULL; 2470 } 2471 2472 void JNIid::oops_do(OopClosure* f) { 2473 for (JNIid* cur = this; cur != NULL; cur = cur->next()) { 2474 f->do_oop(cur->holder_addr()); 2475 } 2476 } 2477 2478 void JNIid::deallocate(JNIid* current) { 2479 while (current != NULL) { 2480 JNIid* next = current->next(); 2481 delete current; 2482 current = next; 2483 } 2484 } 2485 2486 2487 void JNIid::verify(klassOop holder) { 2488 int first_field_offset = instanceMirrorKlass::offset_of_static_fields(); 2489 int end_field_offset; 2490 end_field_offset = first_field_offset + (instanceKlass::cast(holder)->static_field_size() * wordSize); 2491 2492 JNIid* current = this; 2493 while (current != NULL) { 2494 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 2495 #ifdef ASSERT 2496 int o = current->offset(); 2497 if (current->is_static_field_id()) { 2498 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 2499 } 2500 #endif 2501 current = current->next(); 2502 } 2503 } 2504 2505 2506 #ifdef ASSERT 2507 void instanceKlass::set_init_state(ClassState state) { 2508 bool good_state = as_klassOop()->is_shared() ? (_init_state <= state) 2509 : (_init_state < state); 2510 assert(good_state || state == allocated, "illegal state transition"); 2511 _init_state = state; 2512 } 2513 #endif 2514 2515 2516 // RedefineClasses() support for previous versions: 2517 2518 // Add an information node that contains weak references to the 2519 // interesting parts of the previous version of the_class. 2520 // This is also where we clean out any unused weak references. 2521 // Note that while we delete nodes from the _previous_versions 2522 // array, we never delete the array itself until the klass is 2523 // unloaded. The has_been_redefined() query depends on that fact. 2524 // 2525 void instanceKlass::add_previous_version(instanceKlassHandle ikh, 2526 BitMap* emcp_methods, int emcp_method_count) { 2527 assert(Thread::current()->is_VM_thread(), 2528 "only VMThread can add previous versions"); 2529 2530 if (_previous_versions == NULL) { 2531 // This is the first previous version so make some space. 2532 // Start with 2 elements under the assumption that the class 2533 // won't be redefined much. 2534 _previous_versions = new (ResourceObj::C_HEAP) 2535 GrowableArray<PreviousVersionNode *>(2, true); 2536 } 2537 2538 // RC_TRACE macro has an embedded ResourceMark 2539 RC_TRACE(0x00000100, ("adding previous version ref for %s @%d, EMCP_cnt=%d", 2540 ikh->external_name(), _previous_versions->length(), emcp_method_count)); 2541 constantPoolHandle cp_h(ikh->constants()); 2542 jobject cp_ref; 2543 if (cp_h->is_shared()) { 2544 // a shared ConstantPool requires a regular reference; a weak 2545 // reference would be collectible 2546 cp_ref = JNIHandles::make_global(cp_h); 2547 } else { 2548 cp_ref = JNIHandles::make_weak_global(cp_h); 2549 } 2550 PreviousVersionNode * pv_node = NULL; 2551 objArrayOop old_methods = ikh->methods(); 2552 2553 if (emcp_method_count == 0) { 2554 // non-shared ConstantPool gets a weak reference 2555 pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), NULL); 2556 RC_TRACE(0x00000400, 2557 ("add: all methods are obsolete; flushing any EMCP weak refs")); 2558 } else { 2559 int local_count = 0; 2560 GrowableArray<jweak>* method_refs = new (ResourceObj::C_HEAP) 2561 GrowableArray<jweak>(emcp_method_count, true); 2562 for (int i = 0; i < old_methods->length(); i++) { 2563 if (emcp_methods->at(i)) { 2564 // this old method is EMCP so save a weak ref 2565 methodOop old_method = (methodOop) old_methods->obj_at(i); 2566 methodHandle old_method_h(old_method); 2567 jweak method_ref = JNIHandles::make_weak_global(old_method_h); 2568 method_refs->append(method_ref); 2569 if (++local_count >= emcp_method_count) { 2570 // no more EMCP methods so bail out now 2571 break; 2572 } 2573 } 2574 } 2575 // non-shared ConstantPool gets a weak reference 2576 pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), method_refs); 2577 } 2578 2579 _previous_versions->append(pv_node); 2580 2581 // Using weak references allows the interesting parts of previous 2582 // classes to be GC'ed when they are no longer needed. Since the 2583 // caller is the VMThread and we are at a safepoint, this is a good 2584 // time to clear out unused weak references. 2585 2586 RC_TRACE(0x00000400, ("add: previous version length=%d", 2587 _previous_versions->length())); 2588 2589 // skip the last entry since we just added it 2590 for (int i = _previous_versions->length() - 2; i >= 0; i--) { 2591 // check the previous versions array for a GC'ed weak refs 2592 pv_node = _previous_versions->at(i); 2593 cp_ref = pv_node->prev_constant_pool(); 2594 assert(cp_ref != NULL, "cp ref was unexpectedly cleared"); 2595 if (cp_ref == NULL) { 2596 delete pv_node; 2597 _previous_versions->remove_at(i); 2598 // Since we are traversing the array backwards, we don't have to 2599 // do anything special with the index. 2600 continue; // robustness 2601 } 2602 2603 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref); 2604 if (cp == NULL) { 2605 // this entry has been GC'ed so remove it 2606 delete pv_node; 2607 _previous_versions->remove_at(i); 2608 // Since we are traversing the array backwards, we don't have to 2609 // do anything special with the index. 2610 continue; 2611 } else { 2612 RC_TRACE(0x00000400, ("add: previous version @%d is alive", i)); 2613 } 2614 2615 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods(); 2616 if (method_refs != NULL) { 2617 RC_TRACE(0x00000400, ("add: previous methods length=%d", 2618 method_refs->length())); 2619 for (int j = method_refs->length() - 1; j >= 0; j--) { 2620 jweak method_ref = method_refs->at(j); 2621 assert(method_ref != NULL, "weak method ref was unexpectedly cleared"); 2622 if (method_ref == NULL) { 2623 method_refs->remove_at(j); 2624 // Since we are traversing the array backwards, we don't have to 2625 // do anything special with the index. 2626 continue; // robustness 2627 } 2628 2629 methodOop method = (methodOop)JNIHandles::resolve(method_ref); 2630 if (method == NULL || emcp_method_count == 0) { 2631 // This method entry has been GC'ed or the current 2632 // RedefineClasses() call has made all methods obsolete 2633 // so remove it. 2634 JNIHandles::destroy_weak_global(method_ref); 2635 method_refs->remove_at(j); 2636 } else { 2637 // RC_TRACE macro has an embedded ResourceMark 2638 RC_TRACE(0x00000400, 2639 ("add: %s(%s): previous method @%d in version @%d is alive", 2640 method->name()->as_C_string(), method->signature()->as_C_string(), 2641 j, i)); 2642 } 2643 } 2644 } 2645 } 2646 2647 int obsolete_method_count = old_methods->length() - emcp_method_count; 2648 2649 if (emcp_method_count != 0 && obsolete_method_count != 0 && 2650 _previous_versions->length() > 1) { 2651 // We have a mix of obsolete and EMCP methods. If there is more 2652 // than the previous version that we just added, then we have to 2653 // clear out any matching EMCP method entries the hard way. 2654 int local_count = 0; 2655 for (int i = 0; i < old_methods->length(); i++) { 2656 if (!emcp_methods->at(i)) { 2657 // only obsolete methods are interesting 2658 methodOop old_method = (methodOop) old_methods->obj_at(i); 2659 Symbol* m_name = old_method->name(); 2660 Symbol* m_signature = old_method->signature(); 2661 2662 // skip the last entry since we just added it 2663 for (int j = _previous_versions->length() - 2; j >= 0; j--) { 2664 // check the previous versions array for a GC'ed weak refs 2665 pv_node = _previous_versions->at(j); 2666 cp_ref = pv_node->prev_constant_pool(); 2667 assert(cp_ref != NULL, "cp ref was unexpectedly cleared"); 2668 if (cp_ref == NULL) { 2669 delete pv_node; 2670 _previous_versions->remove_at(j); 2671 // Since we are traversing the array backwards, we don't have to 2672 // do anything special with the index. 2673 continue; // robustness 2674 } 2675 2676 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref); 2677 if (cp == NULL) { 2678 // this entry has been GC'ed so remove it 2679 delete pv_node; 2680 _previous_versions->remove_at(j); 2681 // Since we are traversing the array backwards, we don't have to 2682 // do anything special with the index. 2683 continue; 2684 } 2685 2686 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods(); 2687 if (method_refs == NULL) { 2688 // We have run into a PreviousVersion generation where 2689 // all methods were made obsolete during that generation's 2690 // RedefineClasses() operation. At the time of that 2691 // operation, all EMCP methods were flushed so we don't 2692 // have to go back any further. 2693 // 2694 // A NULL method_refs is different than an empty method_refs. 2695 // We cannot infer any optimizations about older generations 2696 // from an empty method_refs for the current generation. 2697 break; 2698 } 2699 2700 for (int k = method_refs->length() - 1; k >= 0; k--) { 2701 jweak method_ref = method_refs->at(k); 2702 assert(method_ref != NULL, 2703 "weak method ref was unexpectedly cleared"); 2704 if (method_ref == NULL) { 2705 method_refs->remove_at(k); 2706 // Since we are traversing the array backwards, we don't 2707 // have to do anything special with the index. 2708 continue; // robustness 2709 } 2710 2711 methodOop method = (methodOop)JNIHandles::resolve(method_ref); 2712 if (method == NULL) { 2713 // this method entry has been GC'ed so skip it 2714 JNIHandles::destroy_weak_global(method_ref); 2715 method_refs->remove_at(k); 2716 continue; 2717 } 2718 2719 if (method->name() == m_name && 2720 method->signature() == m_signature) { 2721 // The current RedefineClasses() call has made all EMCP 2722 // versions of this method obsolete so mark it as obsolete 2723 // and remove the weak ref. 2724 RC_TRACE(0x00000400, 2725 ("add: %s(%s): flush obsolete method @%d in version @%d", 2726 m_name->as_C_string(), m_signature->as_C_string(), k, j)); 2727 2728 method->set_is_obsolete(); 2729 JNIHandles::destroy_weak_global(method_ref); 2730 method_refs->remove_at(k); 2731 break; 2732 } 2733 } 2734 2735 // The previous loop may not find a matching EMCP method, but 2736 // that doesn't mean that we can optimize and not go any 2737 // further back in the PreviousVersion generations. The EMCP 2738 // method for this generation could have already been GC'ed, 2739 // but there still may be an older EMCP method that has not 2740 // been GC'ed. 2741 } 2742 2743 if (++local_count >= obsolete_method_count) { 2744 // no more obsolete methods so bail out now 2745 break; 2746 } 2747 } 2748 } 2749 } 2750 } // end add_previous_version() 2751 2752 2753 // Determine if instanceKlass has a previous version. 2754 bool instanceKlass::has_previous_version() const { 2755 if (_previous_versions == NULL) { 2756 // no previous versions array so answer is easy 2757 return false; 2758 } 2759 2760 for (int i = _previous_versions->length() - 1; i >= 0; i--) { 2761 // Check the previous versions array for an info node that hasn't 2762 // been GC'ed 2763 PreviousVersionNode * pv_node = _previous_versions->at(i); 2764 2765 jobject cp_ref = pv_node->prev_constant_pool(); 2766 assert(cp_ref != NULL, "cp reference was unexpectedly cleared"); 2767 if (cp_ref == NULL) { 2768 continue; // robustness 2769 } 2770 2771 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref); 2772 if (cp != NULL) { 2773 // we have at least one previous version 2774 return true; 2775 } 2776 2777 // We don't have to check the method refs. If the constant pool has 2778 // been GC'ed then so have the methods. 2779 } 2780 2781 // all of the underlying nodes' info has been GC'ed 2782 return false; 2783 } // end has_previous_version() 2784 2785 methodOop instanceKlass::method_with_idnum(int idnum) { 2786 methodOop m = NULL; 2787 if (idnum < methods()->length()) { 2788 m = (methodOop) methods()->obj_at(idnum); 2789 } 2790 if (m == NULL || m->method_idnum() != idnum) { 2791 for (int index = 0; index < methods()->length(); ++index) { 2792 m = (methodOop) methods()->obj_at(index); 2793 if (m->method_idnum() == idnum) { 2794 return m; 2795 } 2796 } 2797 } 2798 return m; 2799 } 2800 2801 2802 // Set the annotation at 'idnum' to 'anno'. 2803 // We don't want to create or extend the array if 'anno' is NULL, since that is the 2804 // default value. However, if the array exists and is long enough, we must set NULL values. 2805 void instanceKlass::set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p) { 2806 objArrayOop md = *md_p; 2807 if (md != NULL && md->length() > idnum) { 2808 md->obj_at_put(idnum, anno); 2809 } else if (anno != NULL) { 2810 // create the array 2811 int length = MAX2(idnum+1, (int)_idnum_allocated_count); 2812 md = oopFactory::new_system_objArray(length, Thread::current()); 2813 if (*md_p != NULL) { 2814 // copy the existing entries 2815 for (int index = 0; index < (*md_p)->length(); index++) { 2816 md->obj_at_put(index, (*md_p)->obj_at(index)); 2817 } 2818 } 2819 set_annotations(md, md_p); 2820 md->obj_at_put(idnum, anno); 2821 } // if no array and idnum isn't included there is nothing to do 2822 } 2823 2824 // Construct a PreviousVersionNode entry for the array hung off 2825 // the instanceKlass. 2826 PreviousVersionNode::PreviousVersionNode(jobject prev_constant_pool, 2827 bool prev_cp_is_weak, GrowableArray<jweak>* prev_EMCP_methods) { 2828 2829 _prev_constant_pool = prev_constant_pool; 2830 _prev_cp_is_weak = prev_cp_is_weak; 2831 _prev_EMCP_methods = prev_EMCP_methods; 2832 } 2833 2834 2835 // Destroy a PreviousVersionNode 2836 PreviousVersionNode::~PreviousVersionNode() { 2837 if (_prev_constant_pool != NULL) { 2838 if (_prev_cp_is_weak) { 2839 JNIHandles::destroy_weak_global(_prev_constant_pool); 2840 } else { 2841 JNIHandles::destroy_global(_prev_constant_pool); 2842 } 2843 } 2844 2845 if (_prev_EMCP_methods != NULL) { 2846 for (int i = _prev_EMCP_methods->length() - 1; i >= 0; i--) { 2847 jweak method_ref = _prev_EMCP_methods->at(i); 2848 if (method_ref != NULL) { 2849 JNIHandles::destroy_weak_global(method_ref); 2850 } 2851 } 2852 delete _prev_EMCP_methods; 2853 } 2854 } 2855 2856 2857 // Construct a PreviousVersionInfo entry 2858 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) { 2859 _prev_constant_pool_handle = constantPoolHandle(); // NULL handle 2860 _prev_EMCP_method_handles = NULL; 2861 2862 jobject cp_ref = pv_node->prev_constant_pool(); 2863 assert(cp_ref != NULL, "constant pool ref was unexpectedly cleared"); 2864 if (cp_ref == NULL) { 2865 return; // robustness 2866 } 2867 2868 constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref); 2869 if (cp == NULL) { 2870 // Weak reference has been GC'ed. Since the constant pool has been 2871 // GC'ed, the methods have also been GC'ed. 2872 return; 2873 } 2874 2875 // make the constantPoolOop safe to return 2876 _prev_constant_pool_handle = constantPoolHandle(cp); 2877 2878 GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods(); 2879 if (method_refs == NULL) { 2880 // the instanceKlass did not have any EMCP methods 2881 return; 2882 } 2883 2884 _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10); 2885 2886 int n_methods = method_refs->length(); 2887 for (int i = 0; i < n_methods; i++) { 2888 jweak method_ref = method_refs->at(i); 2889 assert(method_ref != NULL, "weak method ref was unexpectedly cleared"); 2890 if (method_ref == NULL) { 2891 continue; // robustness 2892 } 2893 2894 methodOop method = (methodOop)JNIHandles::resolve(method_ref); 2895 if (method == NULL) { 2896 // this entry has been GC'ed so skip it 2897 continue; 2898 } 2899 2900 // make the methodOop safe to return 2901 _prev_EMCP_method_handles->append(methodHandle(method)); 2902 } 2903 } 2904 2905 2906 // Destroy a PreviousVersionInfo 2907 PreviousVersionInfo::~PreviousVersionInfo() { 2908 // Since _prev_EMCP_method_handles is not C-heap allocated, we 2909 // don't have to delete it. 2910 } 2911 2912 2913 // Construct a helper for walking the previous versions array 2914 PreviousVersionWalker::PreviousVersionWalker(instanceKlass *ik) { 2915 _previous_versions = ik->previous_versions(); 2916 _current_index = 0; 2917 // _hm needs no initialization 2918 _current_p = NULL; 2919 } 2920 2921 2922 // Destroy a PreviousVersionWalker 2923 PreviousVersionWalker::~PreviousVersionWalker() { 2924 // Delete the current info just in case the caller didn't walk to 2925 // the end of the previous versions list. No harm if _current_p is 2926 // already NULL. 2927 delete _current_p; 2928 2929 // When _hm is destroyed, all the Handles returned in 2930 // PreviousVersionInfo objects will be destroyed. 2931 // Also, after this destructor is finished it will be 2932 // safe to delete the GrowableArray allocated in the 2933 // PreviousVersionInfo objects. 2934 } 2935 2936 2937 // Return the interesting information for the next previous version 2938 // of the klass. Returns NULL if there are no more previous versions. 2939 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() { 2940 if (_previous_versions == NULL) { 2941 // no previous versions so nothing to return 2942 return NULL; 2943 } 2944 2945 delete _current_p; // cleanup the previous info for the caller 2946 _current_p = NULL; // reset to NULL so we don't delete same object twice 2947 2948 int length = _previous_versions->length(); 2949 2950 while (_current_index < length) { 2951 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++); 2952 PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP) 2953 PreviousVersionInfo(pv_node); 2954 2955 constantPoolHandle cp_h = pv_info->prev_constant_pool_handle(); 2956 if (cp_h.is_null()) { 2957 delete pv_info; 2958 2959 // The underlying node's info has been GC'ed so try the next one. 2960 // We don't have to check the methods. If the constant pool has 2961 // GC'ed then so have the methods. 2962 continue; 2963 } 2964 2965 // Found a node with non GC'ed info so return it. The caller will 2966 // need to delete pv_info when they are done with it. 2967 _current_p = pv_info; 2968 return pv_info; 2969 } 2970 2971 // all of the underlying nodes' info has been GC'ed 2972 return NULL; 2973 } // end next_previous_version()