1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "aot/aotLoader.hpp"
  27 #include "classfile/classLoader.hpp"
  28 #include "classfile/stringTable.hpp"
  29 #include "classfile/systemDictionary.hpp"
  30 #include "code/codeCache.hpp"
  31 #include "compiler/compileBroker.hpp"
  32 #include "compiler/compilerOracle.hpp"
  33 #include "gc/shared/genCollectedHeap.hpp"
  34 #include "interpreter/bytecodeHistogram.hpp"
  35 #if INCLUDE_JVMCI
  36 #include "jvmci/jvmciCompiler.hpp"
  37 #include "jvmci/jvmciRuntime.hpp"
  38 #endif
  39 #include "logging/log.hpp"
  40 #include "memory/oopFactory.hpp"
  41 #include "memory/resourceArea.hpp"
  42 #include "memory/universe.hpp"
  43 #include "oops/constantPool.hpp"
  44 #include "oops/generateOopMap.hpp"
  45 #include "oops/instanceKlass.hpp"
  46 #include "oops/instanceOop.hpp"
  47 #include "oops/method.hpp"
  48 #include "oops/objArrayOop.hpp"
  49 #include "oops/oop.inline.hpp"
  50 #include "oops/symbol.hpp"
  51 #include "prims/jvmtiExport.hpp"
  52 #include "runtime/arguments.hpp"
  53 #include "runtime/biasedLocking.hpp"
  54 #include "runtime/compilationPolicy.hpp"
  55 #include "runtime/deoptimization.hpp"
  56 #include "runtime/fprofiler.hpp"
  57 #include "runtime/init.hpp"
  58 #include "runtime/interfaceSupport.hpp"
  59 #include "runtime/java.hpp"
  60 #include "runtime/memprofiler.hpp"
  61 #include "runtime/sharedRuntime.hpp"
  62 #include "runtime/statSampler.hpp"
  63 #include "runtime/sweeper.hpp"
  64 #include "runtime/task.hpp"
  65 #include "runtime/thread.inline.hpp"
  66 #include "runtime/timer.hpp"
  67 #include "runtime/vm_operations.hpp"
  68 #include "services/memTracker.hpp"
  69 #include "trace/traceMacros.hpp"
  70 #include "trace/tracing.hpp"
  71 #include "utilities/dtrace.hpp"
  72 #include "utilities/globalDefinitions.hpp"
  73 #include "utilities/histogram.hpp"
  74 #include "utilities/macros.hpp"
  75 #include "utilities/vmError.hpp"
  76 #ifdef COMPILER1
  77 #include "c1/c1_Compiler.hpp"
  78 #include "c1/c1_Runtime1.hpp"
  79 #endif
  80 #ifdef COMPILER2
  81 #include "code/compiledIC.hpp"
  82 #include "compiler/methodLiveness.hpp"
  83 #include "opto/compile.hpp"
  84 #include "opto/indexSet.hpp"
  85 #include "opto/runtime.hpp"
  86 #endif
  87 
  88 GrowableArray<Method*>* collected_profiled_methods;
  89 
  90 int compare_methods(Method** a, Method** b) {
  91   // %%% there can be 32-bit overflow here
  92   return ((*b)->invocation_count() + (*b)->compiled_invocation_count())
  93        - ((*a)->invocation_count() + (*a)->compiled_invocation_count());
  94 }
  95 
  96 void collect_profiled_methods(Method* m) {
  97   Thread* thread = Thread::current();
  98   methodHandle mh(thread, m);
  99   if ((m->method_data() != NULL) &&
 100       (PrintMethodData || CompilerOracle::should_print(mh))) {
 101     collected_profiled_methods->push(m);
 102   }
 103 }
 104 
 105 void print_method_profiling_data() {
 106   if (ProfileInterpreter COMPILER1_PRESENT(|| C1UpdateMethodData) &&
 107      (PrintMethodData || CompilerOracle::should_print_methods())) {
 108     ResourceMark rm;
 109     HandleMark hm;
 110     collected_profiled_methods = new GrowableArray<Method*>(1024);
 111     SystemDictionary::methods_do(collect_profiled_methods);
 112     collected_profiled_methods->sort(&compare_methods);
 113 
 114     int count = collected_profiled_methods->length();
 115     int total_size = 0;
 116     if (count > 0) {
 117       for (int index = 0; index < count; index++) {
 118         Method* m = collected_profiled_methods->at(index);
 119         ttyLocker ttyl;
 120         tty->print_cr("------------------------------------------------------------------------");
 121         m->print_invocation_count();
 122         tty->print_cr("  mdo size: %d bytes", m->method_data()->size_in_bytes());
 123         tty->cr();
 124         // Dump data on parameters if any
 125         if (m->method_data() != NULL && m->method_data()->parameters_type_data() != NULL) {
 126           tty->fill_to(2);
 127           m->method_data()->parameters_type_data()->print_data_on(tty);
 128         }
 129         m->print_codes();
 130         total_size += m->method_data()->size_in_bytes();
 131       }
 132       tty->print_cr("------------------------------------------------------------------------");
 133       tty->print_cr("Total MDO size: %d bytes", total_size);
 134     }
 135   }
 136 }
 137 
 138 
 139 #ifndef PRODUCT
 140 
 141 // Statistics printing (method invocation histogram)
 142 
 143 GrowableArray<Method*>* collected_invoked_methods;
 144 
 145 void collect_invoked_methods(Method* m) {
 146   if (m->invocation_count() + m->compiled_invocation_count() >= 1 ) {
 147     collected_invoked_methods->push(m);
 148   }
 149 }
 150 
 151 
 152 
 153 
 154 void print_method_invocation_histogram() {
 155   ResourceMark rm;
 156   HandleMark hm;
 157   collected_invoked_methods = new GrowableArray<Method*>(1024);
 158   SystemDictionary::methods_do(collect_invoked_methods);
 159   collected_invoked_methods->sort(&compare_methods);
 160   //
 161   tty->cr();
 162   tty->print_cr("Histogram Over Method Invocation Counters (cutoff = " INTX_FORMAT "):", MethodHistogramCutoff);
 163   tty->cr();
 164   tty->print_cr("____Count_(I+C)____Method________________________Module_________________");
 165   unsigned total = 0, int_total = 0, comp_total = 0, static_total = 0, final_total = 0,
 166       synch_total = 0, nativ_total = 0, acces_total = 0;
 167   for (int index = 0; index < collected_invoked_methods->length(); index++) {
 168     Method* m = collected_invoked_methods->at(index);
 169     int c = m->invocation_count() + m->compiled_invocation_count();
 170     if (c >= MethodHistogramCutoff) m->print_invocation_count();
 171     int_total  += m->invocation_count();
 172     comp_total += m->compiled_invocation_count();
 173     if (m->is_final())        final_total  += c;
 174     if (m->is_static())       static_total += c;
 175     if (m->is_synchronized()) synch_total  += c;
 176     if (m->is_native())       nativ_total  += c;
 177     if (m->is_accessor())     acces_total  += c;
 178   }
 179   tty->cr();
 180   total = int_total + comp_total;
 181   tty->print_cr("Invocations summary:");
 182   tty->print_cr("\t%9d (%4.1f%%) interpreted",  int_total,    100.0 * int_total    / total);
 183   tty->print_cr("\t%9d (%4.1f%%) compiled",     comp_total,   100.0 * comp_total   / total);
 184   tty->print_cr("\t%9d (100%%)  total",         total);
 185   tty->print_cr("\t%9d (%4.1f%%) synchronized", synch_total,  100.0 * synch_total  / total);
 186   tty->print_cr("\t%9d (%4.1f%%) final",        final_total,  100.0 * final_total  / total);
 187   tty->print_cr("\t%9d (%4.1f%%) static",       static_total, 100.0 * static_total / total);
 188   tty->print_cr("\t%9d (%4.1f%%) native",       nativ_total,  100.0 * nativ_total  / total);
 189   tty->print_cr("\t%9d (%4.1f%%) accessor",     acces_total,  100.0 * acces_total  / total);
 190   tty->cr();
 191   SharedRuntime::print_call_statistics(comp_total);
 192 }
 193 
 194 void print_bytecode_count() {
 195   if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
 196     tty->print_cr("[BytecodeCounter::counter_value = %d]", BytecodeCounter::counter_value());
 197   }
 198 }
 199 
 200 AllocStats alloc_stats;
 201 
 202 
 203 
 204 // General statistics printing (profiling ...)
 205 void print_statistics() {
 206 #ifdef ASSERT
 207 
 208   if (CountRuntimeCalls) {
 209     extern Histogram *RuntimeHistogram;
 210     RuntimeHistogram->print();
 211   }
 212 
 213   if (CountJNICalls) {
 214     extern Histogram *JNIHistogram;
 215     JNIHistogram->print();
 216   }
 217 
 218   if (CountJVMCalls) {
 219     extern Histogram *JVMHistogram;
 220     JVMHistogram->print();
 221   }
 222 
 223 #endif
 224 
 225   if (MemProfiling) {
 226     MemProfiler::disengage();
 227   }
 228 
 229   if (CITime) {
 230     CompileBroker::print_times();
 231   }
 232 
 233 #ifdef COMPILER1
 234   if ((PrintC1Statistics || LogVMOutput || LogCompilation) && UseCompiler) {
 235     FlagSetting fs(DisplayVMOutput, DisplayVMOutput && PrintC1Statistics);
 236     Runtime1::print_statistics();
 237     Deoptimization::print_statistics();
 238     SharedRuntime::print_statistics();
 239   }
 240 #endif /* COMPILER1 */
 241 
 242 #ifdef COMPILER2
 243   if ((PrintOptoStatistics || LogVMOutput || LogCompilation) && UseCompiler) {
 244     FlagSetting fs(DisplayVMOutput, DisplayVMOutput && PrintOptoStatistics);
 245     Compile::print_statistics();
 246 #ifndef COMPILER1
 247     Deoptimization::print_statistics();
 248     SharedRuntime::print_statistics();
 249 #endif //COMPILER1
 250     os::print_statistics();
 251   }
 252 
 253   if (PrintLockStatistics || PrintPreciseBiasedLockingStatistics || PrintPreciseRTMLockingStatistics) {
 254     OptoRuntime::print_named_counters();
 255   }
 256 
 257   if (TimeLivenessAnalysis) {
 258     MethodLiveness::print_times();
 259   }
 260 #ifdef ASSERT
 261   if (CollectIndexSetStatistics) {
 262     IndexSet::print_statistics();
 263   }
 264 #endif // ASSERT
 265 #else
 266 #ifdef INCLUDE_JVMCI
 267 #ifndef COMPILER1
 268   if ((TraceDeoptimization || LogVMOutput || LogCompilation) && UseCompiler) {
 269     FlagSetting fs(DisplayVMOutput, DisplayVMOutput && TraceDeoptimization);
 270     Deoptimization::print_statistics();
 271     SharedRuntime::print_statistics();
 272   }
 273 #endif
 274 #endif
 275 #endif
 276 
 277   if (PrintAOTStatistics) {
 278     AOTLoader::print_statistics();
 279   }
 280 
 281   if (PrintNMethodStatistics) {
 282     nmethod::print_statistics();
 283   }
 284   if (CountCompiledCalls) {
 285     print_method_invocation_histogram();
 286   }
 287 
 288   print_method_profiling_data();
 289 
 290   if (TimeCompilationPolicy) {
 291     CompilationPolicy::policy()->print_time();
 292   }
 293   if (TimeOopMap) {
 294     GenerateOopMap::print_time();
 295   }
 296   if (ProfilerCheckIntervals) {
 297     PeriodicTask::print_intervals();
 298   }
 299   if (PrintSymbolTableSizeHistogram) {
 300     SymbolTable::print_histogram();
 301   }
 302   if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
 303     BytecodeCounter::print();
 304   }
 305   if (PrintBytecodePairHistogram) {
 306     BytecodePairHistogram::print();
 307   }
 308 
 309   if (PrintCodeCache) {
 310     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 311     CodeCache::print();
 312   }
 313 
 314   if (PrintMethodFlushingStatistics) {
 315     NMethodSweeper::print();
 316   }
 317 
 318   if (PrintCodeCache2) {
 319     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 320     CodeCache::print_internals();
 321   }
 322 
 323   if (PrintVtableStats) {
 324     klassVtable::print_statistics();
 325     klassItable::print_statistics();
 326   }
 327   if (VerifyOops) {
 328     tty->print_cr("+VerifyOops count: %d", StubRoutines::verify_oop_count());
 329   }
 330 
 331   print_bytecode_count();
 332   if (PrintMallocStatistics) {
 333     tty->print("allocation stats: ");
 334     alloc_stats.print();
 335     tty->cr();
 336   }
 337 
 338   if (PrintSystemDictionaryAtExit) {
 339     SystemDictionary::print();
 340   }
 341 
 342   if (LogTouchedMethods && PrintTouchedMethodsAtExit) {
 343     Method::print_touched_methods(tty);
 344   }
 345 
 346   if (PrintBiasedLockingStatistics) {
 347     BiasedLocking::print_counters();
 348   }
 349 
 350   // Native memory tracking data
 351   if (PrintNMTStatistics) {
 352     MemTracker::final_report(tty);
 353   }
 354 }
 355 
 356 #else // PRODUCT MODE STATISTICS
 357 
 358 void print_statistics() {
 359 
 360   if (PrintMethodData) {
 361     print_method_profiling_data();
 362   }
 363 
 364   if (CITime) {
 365     CompileBroker::print_times();
 366   }
 367 
 368   if (PrintCodeCache) {
 369     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 370     CodeCache::print();
 371   }
 372 
 373   if (PrintMethodFlushingStatistics) {
 374     NMethodSweeper::print();
 375   }
 376 
 377 #ifdef COMPILER2
 378   if (PrintPreciseBiasedLockingStatistics || PrintPreciseRTMLockingStatistics) {
 379     OptoRuntime::print_named_counters();
 380   }
 381 #endif
 382   if (PrintBiasedLockingStatistics) {
 383     BiasedLocking::print_counters();
 384   }
 385 
 386   // Native memory tracking data
 387   if (PrintNMTStatistics) {
 388     MemTracker::final_report(tty);
 389   }
 390 
 391   if (LogTouchedMethods && PrintTouchedMethodsAtExit) {
 392     Method::print_touched_methods(tty);
 393   }
 394 }
 395 
 396 #endif
 397 
 398 // Note: before_exit() can be executed only once, if more than one threads
 399 //       are trying to shutdown the VM at the same time, only one thread
 400 //       can run before_exit() and all other threads must wait.
 401 void before_exit(JavaThread* thread) {
 402   #define BEFORE_EXIT_NOT_RUN 0
 403   #define BEFORE_EXIT_RUNNING 1
 404   #define BEFORE_EXIT_DONE    2
 405   static jint volatile _before_exit_status = BEFORE_EXIT_NOT_RUN;
 406 
 407   // Note: don't use a Mutex to guard the entire before_exit(), as
 408   // JVMTI post_thread_end_event and post_vm_death_event will run native code.
 409   // A CAS or OSMutex would work just fine but then we need to manipulate
 410   // thread state for Safepoint. Here we use Monitor wait() and notify_all()
 411   // for synchronization.
 412   { MutexLocker ml(BeforeExit_lock);
 413     switch (_before_exit_status) {
 414     case BEFORE_EXIT_NOT_RUN:
 415       _before_exit_status = BEFORE_EXIT_RUNNING;
 416       break;
 417     case BEFORE_EXIT_RUNNING:
 418       while (_before_exit_status == BEFORE_EXIT_RUNNING) {
 419         BeforeExit_lock->wait();
 420       }
 421       assert(_before_exit_status == BEFORE_EXIT_DONE, "invalid state");
 422       return;
 423     case BEFORE_EXIT_DONE:
 424       // need block to avoid SS compiler bug
 425       {
 426         return;
 427       }
 428     }
 429   }
 430 
 431 #if INCLUDE_JVMCI
 432   // We are not using CATCH here because we want the exit to continue normally.
 433   Thread* THREAD = thread;
 434   JVMCIRuntime::shutdown(THREAD);
 435   if (HAS_PENDING_EXCEPTION) {
 436     Handle exception(THREAD, PENDING_EXCEPTION);
 437     CLEAR_PENDING_EXCEPTION;
 438     java_lang_Throwable::java_printStackTrace(exception, THREAD);
 439   }
 440 #endif
 441 
 442   // Hang forever on exit if we're reporting an error.
 443   if (ShowMessageBoxOnError && is_error_reported()) {
 444     os::infinite_sleep();
 445   }
 446 
 447   EventThreadEnd event;
 448   if (event.should_commit()) {
 449     event.set_thread(THREAD_TRACE_ID(thread));
 450     event.commit();
 451   }
 452 
 453   TRACE_VM_EXIT();
 454 
 455   // Stop the WatcherThread. We do this before disenrolling various
 456   // PeriodicTasks to reduce the likelihood of races.
 457   if (PeriodicTask::num_tasks() > 0) {
 458     WatcherThread::stop();
 459   }
 460 
 461   // Print statistics gathered (profiling ...)
 462   if (Arguments::has_profile()) {
 463     FlatProfiler::disengage();
 464     FlatProfiler::print(10);
 465   }
 466 
 467   // shut down the StatSampler task
 468   StatSampler::disengage();
 469   StatSampler::destroy();
 470 
 471   // Stop concurrent GC threads
 472   GC::gc()->heap()->stop();
 473 
 474   // Print GC/heap related information.
 475   Log(gc, heap, exit) log;
 476   if (log.is_info()) {
 477     ResourceMark rm;
 478     Universe::print_on(log.info_stream());
 479     if (log.is_trace()) {
 480       ClassLoaderDataGraph::dump_on(log.trace_stream());
 481     }
 482   }
 483   AdaptiveSizePolicyOutput::print();
 484 
 485   if (PrintBytecodeHistogram) {
 486     BytecodeHistogram::print();
 487   }
 488 
 489   if (JvmtiExport::should_post_thread_life()) {
 490     JvmtiExport::post_thread_end(thread);
 491   }
 492 
 493   // Always call even when there are not JVMTI environments yet, since environments
 494   // may be attached late and JVMTI must track phases of VM execution
 495   JvmtiExport::post_vm_death();
 496   Threads::shutdown_vm_agents();
 497 
 498   // Terminate the signal thread
 499   // Note: we don't wait until it actually dies.
 500   os::terminate_signal_thread();
 501 
 502   print_statistics();
 503   GC::gc()->heap()->print_tracing_info();
 504 
 505   { MutexLocker ml(BeforeExit_lock);
 506     _before_exit_status = BEFORE_EXIT_DONE;
 507     BeforeExit_lock->notify_all();
 508   }
 509 
 510   if (VerifyStringTableAtExit) {
 511     int fail_cnt = 0;
 512     {
 513       MutexLocker ml(StringTable_lock);
 514       fail_cnt = StringTable::verify_and_compare_entries();
 515     }
 516 
 517     if (fail_cnt != 0) {
 518       tty->print_cr("ERROR: fail_cnt=%d", fail_cnt);
 519       guarantee(fail_cnt == 0, "unexpected StringTable verification failures");
 520     }
 521   }
 522 
 523   #undef BEFORE_EXIT_NOT_RUN
 524   #undef BEFORE_EXIT_RUNNING
 525   #undef BEFORE_EXIT_DONE
 526 }
 527 
 528 void vm_exit(int code) {
 529   Thread* thread =
 530       ThreadLocalStorage::is_initialized() ? Thread::current_or_null() : NULL;
 531   if (thread == NULL) {
 532     // very early initialization failure -- just exit
 533     vm_direct_exit(code);
 534   }
 535 
 536   if (VMThread::vm_thread() != NULL) {
 537     // Fire off a VM_Exit operation to bring VM to a safepoint and exit
 538     VM_Exit op(code);
 539     if (thread->is_Java_thread())
 540       ((JavaThread*)thread)->set_thread_state(_thread_in_vm);
 541     VMThread::execute(&op);
 542     // should never reach here; but in case something wrong with VM Thread.
 543     vm_direct_exit(code);
 544   } else {
 545     // VM thread is gone, just exit
 546     vm_direct_exit(code);
 547   }
 548   ShouldNotReachHere();
 549 }
 550 
 551 void notify_vm_shutdown() {
 552   // For now, just a dtrace probe.
 553   HOTSPOT_VM_SHUTDOWN();
 554   HS_DTRACE_WORKAROUND_TAIL_CALL_BUG();
 555 }
 556 
 557 void vm_direct_exit(int code) {
 558   notify_vm_shutdown();
 559   os::wait_for_keypress_at_exit();
 560   os::exit(code);
 561 }
 562 
 563 void vm_perform_shutdown_actions() {
 564   // Warning: do not call 'exit_globals()' here. All threads are still running.
 565   // Calling 'exit_globals()' will disable thread-local-storage and cause all
 566   // kinds of assertions to trigger in debug mode.
 567   if (is_init_completed()) {
 568     Thread* thread = Thread::current_or_null();
 569     if (thread != NULL && thread->is_Java_thread()) {
 570       // We are leaving the VM, set state to native (in case any OS exit
 571       // handlers call back to the VM)
 572       JavaThread* jt = (JavaThread*)thread;
 573       // Must always be walkable or have no last_Java_frame when in
 574       // thread_in_native
 575       jt->frame_anchor()->make_walkable(jt);
 576       jt->set_thread_state(_thread_in_native);
 577     }
 578   }
 579   notify_vm_shutdown();
 580 }
 581 
 582 void vm_shutdown()
 583 {
 584   vm_perform_shutdown_actions();
 585   os::wait_for_keypress_at_exit();
 586   os::shutdown();
 587 }
 588 
 589 void vm_abort(bool dump_core) {
 590   vm_perform_shutdown_actions();
 591   os::wait_for_keypress_at_exit();
 592 
 593   // Flush stdout and stderr before abort.
 594   fflush(stdout);
 595   fflush(stderr);
 596 
 597   os::abort(dump_core);
 598   ShouldNotReachHere();
 599 }
 600 
 601 void vm_notify_during_shutdown(const char* error, const char* message) {
 602   if (error != NULL) {
 603     tty->print_cr("Error occurred during initialization of VM");
 604     tty->print("%s", error);
 605     if (message != NULL) {
 606       tty->print_cr(": %s", message);
 607     }
 608     else {
 609       tty->cr();
 610     }
 611   }
 612   if (ShowMessageBoxOnError && WizardMode) {
 613     fatal("Error occurred during initialization of VM");
 614   }
 615 }
 616 
 617 void vm_exit_during_initialization() {
 618   vm_notify_during_shutdown(NULL, NULL);
 619 
 620   // Failure during initialization, we don't want to dump core
 621   vm_abort(false);
 622 }
 623 
 624 void vm_exit_during_initialization(Handle exception) {
 625   tty->print_cr("Error occurred during initialization of VM");
 626   // If there are exceptions on this thread it must be cleared
 627   // first and here. Any future calls to EXCEPTION_MARK requires
 628   // that no pending exceptions exist.
 629   Thread *THREAD = Thread::current(); // can't be NULL
 630   if (HAS_PENDING_EXCEPTION) {
 631     CLEAR_PENDING_EXCEPTION;
 632   }
 633   java_lang_Throwable::print_stack_trace(exception, tty);
 634   tty->cr();
 635   vm_notify_during_shutdown(NULL, NULL);
 636 
 637   // Failure during initialization, we don't want to dump core
 638   vm_abort(false);
 639 }
 640 
 641 void vm_exit_during_initialization(Symbol* ex, const char* message) {
 642   ResourceMark rm;
 643   vm_notify_during_shutdown(ex->as_C_string(), message);
 644 
 645   // Failure during initialization, we don't want to dump core
 646   vm_abort(false);
 647 }
 648 
 649 void vm_exit_during_initialization(const char* error, const char* message) {
 650   vm_notify_during_shutdown(error, message);
 651 
 652   // Failure during initialization, we don't want to dump core
 653   vm_abort(false);
 654 }
 655 
 656 void vm_shutdown_during_initialization(const char* error, const char* message) {
 657   vm_notify_during_shutdown(error, message);
 658   vm_shutdown();
 659 }
 660 
 661 JDK_Version JDK_Version::_current;
 662 const char* JDK_Version::_runtime_name;
 663 const char* JDK_Version::_runtime_version;
 664 
 665 void JDK_Version::initialize() {
 666   jdk_version_info info;
 667   assert(!_current.is_valid(), "Don't initialize twice");
 668 
 669   void *lib_handle = os::native_java_library();
 670   jdk_version_info_fn_t func = CAST_TO_FN_PTR(jdk_version_info_fn_t,
 671      os::dll_lookup(lib_handle, "JDK_GetVersionInfo0"));
 672 
 673   assert(func != NULL, "Support for JDK 1.5 or older has been removed after JEP-223");
 674 
 675   (*func)(&info, sizeof(info));
 676 
 677   int major = JDK_VERSION_MAJOR(info.jdk_version);
 678   int minor = JDK_VERSION_MINOR(info.jdk_version);
 679   int security = JDK_VERSION_SECURITY(info.jdk_version);
 680   int build = JDK_VERSION_BUILD(info.jdk_version);
 681 
 682   // Incompatible with pre-4243978 JDK.
 683   if (info.pending_list_uses_discovered_field == 0) {
 684     vm_exit_during_initialization(
 685       "Incompatible JDK is not using Reference.discovered field for pending list");
 686   }
 687   _current = JDK_Version(major, minor, security, info.patch_version, build,
 688                          info.thread_park_blocker == 1,
 689                          info.post_vm_init_hook_enabled == 1);
 690 }
 691 
 692 void JDK_Version_init() {
 693   JDK_Version::initialize();
 694 }
 695 
 696 static int64_t encode_jdk_version(const JDK_Version& v) {
 697   return
 698     ((int64_t)v.major_version()          << (BitsPerByte * 4)) |
 699     ((int64_t)v.minor_version()          << (BitsPerByte * 3)) |
 700     ((int64_t)v.security_version()       << (BitsPerByte * 2)) |
 701     ((int64_t)v.patch_version()          << (BitsPerByte * 1)) |
 702     ((int64_t)v.build_number()           << (BitsPerByte * 0));
 703 }
 704 
 705 int JDK_Version::compare(const JDK_Version& other) const {
 706   assert(is_valid() && other.is_valid(), "Invalid version (uninitialized?)");
 707   uint64_t e = encode_jdk_version(*this);
 708   uint64_t o = encode_jdk_version(other);
 709   return (e > o) ? 1 : ((e == o) ? 0 : -1);
 710 }
 711 
 712 void JDK_Version::to_string(char* buffer, size_t buflen) const {
 713   assert(buffer && buflen > 0, "call with useful buffer");
 714   size_t index = 0;
 715 
 716   if (!is_valid()) {
 717     jio_snprintf(buffer, buflen, "%s", "(uninitialized)");
 718   } else {
 719     int rc = jio_snprintf(
 720         &buffer[index], buflen - index, "%d.%d", _major, _minor);
 721     if (rc == -1) return;
 722     index += rc;
 723     if (_security > 0) {
 724       rc = jio_snprintf(&buffer[index], buflen - index, ".%d", _security);
 725       if (rc == -1) return;
 726       index += rc;
 727     }
 728     if (_patch > 0) {
 729       rc = jio_snprintf(&buffer[index], buflen - index, ".%d", _patch);
 730       if (rc == -1) return;
 731       index += rc;
 732     }
 733     if (_build > 0) {
 734       rc = jio_snprintf(&buffer[index], buflen - index, "+%d", _build);
 735       if (rc == -1) return;
 736       index += rc;
 737     }
 738   }
 739 }