1 /*
   2  * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classLoader.hpp"
  27 #include "classfile/stringTable.hpp"
  28 #include "classfile/systemDictionary.hpp"
  29 #include "code/codeCache.hpp"
  30 #include "compiler/compileBroker.hpp"
  31 #include "compiler/compilerOracle.hpp"
  32 #include "gc/shared/genCollectedHeap.hpp"
  33 #include "interpreter/bytecodeHistogram.hpp"
  34 #if INCLUDE_JVMCI
  35 #include "jvmci/jvmciCompiler.hpp"
  36 #include "jvmci/jvmciRuntime.hpp"
  37 #endif
  38 #include "memory/oopFactory.hpp"
  39 #include "memory/universe.hpp"
  40 #include "oops/constantPool.hpp"
  41 #include "oops/generateOopMap.hpp"
  42 #include "oops/instanceKlass.hpp"
  43 #include "oops/instanceOop.hpp"
  44 #include "oops/method.hpp"
  45 #include "oops/objArrayOop.hpp"
  46 #include "oops/oop.inline.hpp"
  47 #include "oops/symbol.hpp"
  48 #include "prims/jvmtiExport.hpp"
  49 #include "runtime/arguments.hpp"
  50 #include "runtime/biasedLocking.hpp"
  51 #include "runtime/compilationPolicy.hpp"
  52 #include "runtime/fprofiler.hpp"
  53 #include "runtime/init.hpp"
  54 #include "runtime/interfaceSupport.hpp"
  55 #include "runtime/java.hpp"
  56 #include "runtime/memprofiler.hpp"
  57 #include "runtime/sharedRuntime.hpp"
  58 #include "runtime/statSampler.hpp"
  59 #include "runtime/sweeper.hpp"
  60 #include "runtime/task.hpp"
  61 #include "runtime/thread.inline.hpp"
  62 #include "runtime/timer.hpp"
  63 #include "runtime/vm_operations.hpp"
  64 #include "services/memTracker.hpp"
  65 #include "trace/tracing.hpp"
  66 #include "utilities/dtrace.hpp"
  67 #include "utilities/globalDefinitions.hpp"
  68 #include "utilities/histogram.hpp"
  69 #include "utilities/macros.hpp"
  70 #include "utilities/vmError.hpp"
  71 #if INCLUDE_ALL_GCS
  72 #include "gc/cms/concurrentMarkSweepThread.hpp"
  73 #include "gc/parallel/psScavenge.hpp"
  74 #endif // INCLUDE_ALL_GCS
  75 #ifdef COMPILER1
  76 #include "c1/c1_Compiler.hpp"
  77 #include "c1/c1_Runtime1.hpp"
  78 #endif
  79 #ifdef COMPILER2
  80 #include "code/compiledIC.hpp"
  81 #include "compiler/methodLiveness.hpp"
  82 #include "opto/compile.hpp"
  83 #include "opto/indexSet.hpp"
  84 #include "opto/runtime.hpp"
  85 #endif
  86 
  87 GrowableArray<Method*>* collected_profiled_methods;
  88 
  89 int compare_methods(Method** a, Method** b) {
  90   // %%% there can be 32-bit overflow here
  91   return ((*b)->invocation_count() + (*b)->compiled_invocation_count())
  92        - ((*a)->invocation_count() + (*a)->compiled_invocation_count());
  93 }
  94 
  95 void collect_profiled_methods(Method* m) {
  96   Thread* thread = Thread::current();
  97   // This HandleMark prevents a huge amount of handles from being added
  98   // to the metadata_handles() array on the thread.
  99   HandleMark hm(thread);
 100   methodHandle mh(thread, m);
 101   if ((m->method_data() != NULL) &&
 102       (PrintMethodData || CompilerOracle::should_print(mh))) {
 103     collected_profiled_methods->push(m);
 104   }
 105 }
 106 
 107 void print_method_profiling_data() {
 108   if (ProfileInterpreter COMPILER1_PRESENT(|| C1UpdateMethodData) &&
 109      (PrintMethodData || CompilerOracle::should_print_methods())) {
 110     ResourceMark rm;
 111     HandleMark hm;
 112     collected_profiled_methods = new GrowableArray<Method*>(1024);
 113     ClassLoaderDataGraph::methods_do(collect_profiled_methods);
 114     collected_profiled_methods->sort(&compare_methods);
 115 
 116     int count = collected_profiled_methods->length();
 117     int total_size = 0;
 118     if (count > 0) {
 119       for (int index = 0; index < count; index++) {
 120         Method* m = collected_profiled_methods->at(index);
 121         ttyLocker ttyl;
 122         tty->print_cr("------------------------------------------------------------------------");
 123         m->print_invocation_count();
 124         tty->print_cr("  mdo size: %d bytes", m->method_data()->size_in_bytes());
 125         tty->cr();
 126         // Dump data on parameters if any
 127         if (m->method_data() != NULL && m->method_data()->parameters_type_data() != NULL) {
 128           tty->fill_to(2);
 129           m->method_data()->parameters_type_data()->print_data_on(tty);
 130         }
 131         m->print_codes();
 132         total_size += m->method_data()->size_in_bytes();
 133       }
 134       tty->print_cr("------------------------------------------------------------------------");
 135       tty->print_cr("Total MDO size: %d bytes", total_size);
 136     }
 137   }
 138 }
 139 
 140 
 141 #ifndef PRODUCT
 142 
 143 // Statistics printing (method invocation histogram)
 144 
 145 GrowableArray<Method*>* collected_invoked_methods;
 146 
 147 void collect_invoked_methods(Method* m) {
 148   if (m->invocation_count() + m->compiled_invocation_count() >= 1 ) {
 149     collected_invoked_methods->push(m);
 150   }
 151 }
 152 
 153 
 154 
 155 
 156 void print_method_invocation_histogram() {
 157   ResourceMark rm;
 158   HandleMark hm;
 159   collected_invoked_methods = new GrowableArray<Method*>(1024);
 160   SystemDictionary::methods_do(collect_invoked_methods);
 161   collected_invoked_methods->sort(&compare_methods);
 162   //
 163   tty->cr();
 164   tty->print_cr("Histogram Over MethodOop Invocation Counters (cutoff = " INTX_FORMAT "):", MethodHistogramCutoff);
 165   tty->cr();
 166   tty->print_cr("____Count_(I+C)____Method________________________Module_________________");
 167   unsigned total = 0, int_total = 0, comp_total = 0, static_total = 0, final_total = 0,
 168       synch_total = 0, nativ_total = 0, acces_total = 0;
 169   for (int index = 0; index < collected_invoked_methods->length(); index++) {
 170     Method* m = collected_invoked_methods->at(index);
 171     int c = m->invocation_count() + m->compiled_invocation_count();
 172     if (c >= MethodHistogramCutoff) m->print_invocation_count();
 173     int_total  += m->invocation_count();
 174     comp_total += m->compiled_invocation_count();
 175     if (m->is_final())        final_total  += c;
 176     if (m->is_static())       static_total += c;
 177     if (m->is_synchronized()) synch_total  += c;
 178     if (m->is_native())       nativ_total  += c;
 179     if (m->is_accessor())     acces_total  += c;
 180   }
 181   tty->cr();
 182   total = int_total + comp_total;
 183   tty->print_cr("Invocations summary:");
 184   tty->print_cr("\t%9d (%4.1f%%) interpreted",  int_total,    100.0 * int_total    / total);
 185   tty->print_cr("\t%9d (%4.1f%%) compiled",     comp_total,   100.0 * comp_total   / total);
 186   tty->print_cr("\t%9d (100%%)  total",         total);
 187   tty->print_cr("\t%9d (%4.1f%%) synchronized", synch_total,  100.0 * synch_total  / total);
 188   tty->print_cr("\t%9d (%4.1f%%) final",        final_total,  100.0 * final_total  / total);
 189   tty->print_cr("\t%9d (%4.1f%%) static",       static_total, 100.0 * static_total / total);
 190   tty->print_cr("\t%9d (%4.1f%%) native",       nativ_total,  100.0 * nativ_total  / total);
 191   tty->print_cr("\t%9d (%4.1f%%) accessor",     acces_total,  100.0 * acces_total  / total);
 192   tty->cr();
 193   SharedRuntime::print_call_statistics(comp_total);
 194 }
 195 
 196 void print_bytecode_count() {
 197   if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
 198     tty->print_cr("[BytecodeCounter::counter_value = %d]", BytecodeCounter::counter_value());
 199   }
 200 }
 201 
 202 AllocStats alloc_stats;
 203 
 204 
 205 
 206 // General statistics printing (profiling ...)
 207 void print_statistics() {
 208 #ifdef ASSERT
 209 
 210   if (CountRuntimeCalls) {
 211     extern Histogram *RuntimeHistogram;
 212     RuntimeHistogram->print();
 213   }
 214 
 215   if (CountJNICalls) {
 216     extern Histogram *JNIHistogram;
 217     JNIHistogram->print();
 218   }
 219 
 220   if (CountJVMCalls) {
 221     extern Histogram *JVMHistogram;
 222     JVMHistogram->print();
 223   }
 224 
 225 #endif
 226 
 227   if (MemProfiling) {
 228     MemProfiler::disengage();
 229   }
 230 
 231   if (CITime) {
 232     CompileBroker::print_times();
 233   }
 234 
 235 #ifdef COMPILER1
 236   if ((PrintC1Statistics || LogVMOutput || LogCompilation) && UseCompiler) {
 237     FlagSetting fs(DisplayVMOutput, DisplayVMOutput && PrintC1Statistics);
 238     Runtime1::print_statistics();
 239     Deoptimization::print_statistics();
 240     SharedRuntime::print_statistics();
 241   }
 242 #endif /* COMPILER1 */
 243 
 244 #ifdef COMPILER2
 245   if ((PrintOptoStatistics || LogVMOutput || LogCompilation) && UseCompiler) {
 246     FlagSetting fs(DisplayVMOutput, DisplayVMOutput && PrintOptoStatistics);
 247     Compile::print_statistics();
 248 #ifndef COMPILER1
 249     Deoptimization::print_statistics();
 250     SharedRuntime::print_statistics();
 251 #endif //COMPILER1
 252     os::print_statistics();
 253   }
 254 
 255   if (PrintLockStatistics || PrintPreciseBiasedLockingStatistics || PrintPreciseRTMLockingStatistics) {
 256     OptoRuntime::print_named_counters();
 257   }
 258 
 259   if (TimeLivenessAnalysis) {
 260     MethodLiveness::print_times();
 261   }
 262 #ifdef ASSERT
 263   if (CollectIndexSetStatistics) {
 264     IndexSet::print_statistics();
 265   }
 266 #endif // ASSERT
 267 #else
 268 #ifdef INCLUDE_JVMCI
 269 #ifndef COMPILER1
 270   if ((TraceDeoptimization || LogVMOutput || LogCompilation) && UseCompiler) {
 271     FlagSetting fs(DisplayVMOutput, DisplayVMOutput && TraceDeoptimization);
 272     Deoptimization::print_statistics();
 273     SharedRuntime::print_statistics();
 274   }
 275 #endif
 276 #endif
 277 #endif
 278 
 279   if (PrintNMethodStatistics) {
 280     nmethod::print_statistics();
 281   }
 282   if (CountCompiledCalls) {
 283     print_method_invocation_histogram();
 284   }
 285 
 286   print_method_profiling_data();
 287 
 288   if (TimeCompilationPolicy) {
 289     CompilationPolicy::policy()->print_time();
 290   }
 291   if (TimeOopMap) {
 292     GenerateOopMap::print_time();
 293   }
 294   if (ProfilerCheckIntervals) {
 295     PeriodicTask::print_intervals();
 296   }
 297   if (PrintSymbolTableSizeHistogram) {
 298     SymbolTable::print_histogram();
 299   }
 300   if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
 301     BytecodeCounter::print();
 302   }
 303   if (PrintBytecodePairHistogram) {
 304     BytecodePairHistogram::print();
 305   }
 306 
 307   if (PrintCodeCache) {
 308     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 309     CodeCache::print();
 310   }
 311 
 312   if (PrintMethodFlushingStatistics) {
 313     NMethodSweeper::print();
 314   }
 315 
 316   if (PrintCodeCache2) {
 317     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 318     CodeCache::print_internals();
 319   }
 320 
 321   if (PrintVtableStats) {
 322     klassVtable::print_statistics();
 323     klassItable::print_statistics();
 324   }
 325   if (VerifyOops) {
 326     tty->print_cr("+VerifyOops count: %d", StubRoutines::verify_oop_count());
 327   }
 328 
 329   print_bytecode_count();
 330   if (PrintMallocStatistics) {
 331     tty->print("allocation stats: ");
 332     alloc_stats.print();
 333     tty->cr();
 334   }
 335 
 336   if (PrintSystemDictionaryAtExit) {
 337     SystemDictionary::print();
 338   }
 339 
 340   if (LogTouchedMethods && PrintTouchedMethodsAtExit) {
 341     Method::print_touched_methods(tty);
 342   }
 343 
 344   if (PrintBiasedLockingStatistics) {
 345     BiasedLocking::print_counters();
 346   }
 347 
 348   // Native memory tracking data
 349   if (PrintNMTStatistics) {
 350     MemTracker::final_report(tty);
 351   }
 352 }
 353 
 354 #else // PRODUCT MODE STATISTICS
 355 
 356 void print_statistics() {
 357 
 358   if (PrintMethodData) {
 359     print_method_profiling_data();
 360   }
 361 
 362   if (CITime) {
 363     CompileBroker::print_times();
 364   }
 365 
 366   if (PrintCodeCache) {
 367     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 368     CodeCache::print();
 369   }
 370 
 371   if (PrintMethodFlushingStatistics) {
 372     NMethodSweeper::print();
 373   }
 374 
 375 #ifdef COMPILER2
 376   if (PrintPreciseBiasedLockingStatistics || PrintPreciseRTMLockingStatistics) {
 377     OptoRuntime::print_named_counters();
 378   }
 379 #endif
 380   if (PrintBiasedLockingStatistics) {
 381     BiasedLocking::print_counters();
 382   }
 383 
 384   // Native memory tracking data
 385   if (PrintNMTStatistics) {
 386     MemTracker::final_report(tty);
 387   }
 388 
 389   if (LogTouchedMethods && PrintTouchedMethodsAtExit) {
 390     Method::print_touched_methods(tty);
 391   }
 392 }
 393 
 394 #endif
 395 
 396 // Note: before_exit() can be executed only once, if more than one threads
 397 //       are trying to shutdown the VM at the same time, only one thread
 398 //       can run before_exit() and all other threads must wait.
 399 void before_exit(JavaThread * thread) {
 400   #define BEFORE_EXIT_NOT_RUN 0
 401   #define BEFORE_EXIT_RUNNING 1
 402   #define BEFORE_EXIT_DONE    2
 403   static jint volatile _before_exit_status = BEFORE_EXIT_NOT_RUN;
 404 
 405   // Note: don't use a Mutex to guard the entire before_exit(), as
 406   // JVMTI post_thread_end_event and post_vm_death_event will run native code.
 407   // A CAS or OSMutex would work just fine but then we need to manipulate
 408   // thread state for Safepoint. Here we use Monitor wait() and notify_all()
 409   // for synchronization.
 410   { MutexLocker ml(BeforeExit_lock);
 411     switch (_before_exit_status) {
 412     case BEFORE_EXIT_NOT_RUN:
 413       _before_exit_status = BEFORE_EXIT_RUNNING;
 414       break;
 415     case BEFORE_EXIT_RUNNING:
 416       while (_before_exit_status == BEFORE_EXIT_RUNNING) {
 417         BeforeExit_lock->wait();
 418       }
 419       assert(_before_exit_status == BEFORE_EXIT_DONE, "invalid state");
 420       return;
 421     case BEFORE_EXIT_DONE:
 422       return;
 423     }
 424   }
 425 
 426 #if INCLUDE_JVMCI
 427   JVMCIRuntime::shutdown();
 428 #endif
 429 
 430   // Hang forever on exit if we're reporting an error.
 431   if (ShowMessageBoxOnError && is_error_reported()) {
 432     os::infinite_sleep();
 433   }
 434 
 435   // Stop the WatcherThread. We do this before disenrolling various
 436   // PeriodicTasks to reduce the likelihood of races.
 437   if (PeriodicTask::num_tasks() > 0) {
 438     WatcherThread::stop();
 439   }
 440 
 441   // Print statistics gathered (profiling ...)
 442   if (Arguments::has_profile()) {
 443     FlatProfiler::disengage();
 444     FlatProfiler::print(10);
 445   }
 446 
 447   // shut down the StatSampler task
 448   StatSampler::disengage();
 449   StatSampler::destroy();
 450 
 451   // Stop concurrent GC threads
 452   Universe::heap()->stop();
 453 
 454   // Print GC/heap related information.
 455   if (PrintGCDetails) {
 456     Universe::print();
 457     AdaptiveSizePolicyOutput(0);
 458     if (Verbose) {
 459       ClassLoaderDataGraph::dump_on(gclog_or_tty);
 460     }
 461   }
 462 
 463   if (PrintBytecodeHistogram) {
 464     BytecodeHistogram::print();
 465   }
 466 
 467   if (JvmtiExport::should_post_thread_life()) {
 468     JvmtiExport::post_thread_end(thread);
 469   }
 470 
 471 
 472   EventThreadEnd event;
 473   if (event.should_commit()) {
 474       event.set_javalangthread(java_lang_Thread::thread_id(thread->threadObj()));
 475       event.commit();
 476   }
 477 
 478   // Always call even when there are not JVMTI environments yet, since environments
 479   // may be attached late and JVMTI must track phases of VM execution
 480   JvmtiExport::post_vm_death();
 481   Threads::shutdown_vm_agents();
 482 
 483   // Terminate the signal thread
 484   // Note: we don't wait until it actually dies.
 485   os::terminate_signal_thread();
 486 
 487   print_statistics();
 488   Universe::heap()->print_tracing_info();
 489 
 490   { MutexLocker ml(BeforeExit_lock);
 491     _before_exit_status = BEFORE_EXIT_DONE;
 492     BeforeExit_lock->notify_all();
 493   }
 494 
 495   if (VerifyStringTableAtExit) {
 496     int fail_cnt = 0;
 497     {
 498       MutexLocker ml(StringTable_lock);
 499       fail_cnt = StringTable::verify_and_compare_entries();
 500     }
 501 
 502     if (fail_cnt != 0) {
 503       tty->print_cr("ERROR: fail_cnt=%d", fail_cnt);
 504       guarantee(fail_cnt == 0, "unexpected StringTable verification failures");
 505     }
 506   }
 507 
 508   #undef BEFORE_EXIT_NOT_RUN
 509   #undef BEFORE_EXIT_RUNNING
 510   #undef BEFORE_EXIT_DONE
 511 }
 512 
 513 void vm_exit(int code) {
 514   Thread* thread = ThreadLocalStorage::is_initialized() ?
 515     ThreadLocalStorage::get_thread_slow() : NULL;
 516   if (thread == NULL) {
 517     // we have serious problems -- just exit
 518     vm_direct_exit(code);
 519   }
 520 
 521   if (VMThread::vm_thread() != NULL) {
 522     // Fire off a VM_Exit operation to bring VM to a safepoint and exit
 523     VM_Exit op(code);
 524     if (thread->is_Java_thread())
 525       ((JavaThread*)thread)->set_thread_state(_thread_in_vm);
 526     VMThread::execute(&op);
 527     // should never reach here; but in case something wrong with VM Thread.
 528     vm_direct_exit(code);
 529   } else {
 530     // VM thread is gone, just exit
 531     vm_direct_exit(code);
 532   }
 533   ShouldNotReachHere();
 534 }
 535 
 536 void notify_vm_shutdown() {
 537   // For now, just a dtrace probe.
 538   HOTSPOT_VM_SHUTDOWN();
 539   HS_DTRACE_WORKAROUND_TAIL_CALL_BUG();
 540 }
 541 
 542 void vm_direct_exit(int code) {
 543   notify_vm_shutdown();
 544   os::wait_for_keypress_at_exit();
 545   os::exit(code);
 546 }
 547 
 548 void vm_perform_shutdown_actions() {
 549   // Warning: do not call 'exit_globals()' here. All threads are still running.
 550   // Calling 'exit_globals()' will disable thread-local-storage and cause all
 551   // kinds of assertions to trigger in debug mode.
 552   if (is_init_completed()) {
 553     Thread* thread = ThreadLocalStorage::is_initialized() ?
 554                      ThreadLocalStorage::get_thread_slow() : NULL;
 555     if (thread != NULL && thread->is_Java_thread()) {
 556       // We are leaving the VM, set state to native (in case any OS exit
 557       // handlers call back to the VM)
 558       JavaThread* jt = (JavaThread*)thread;
 559       // Must always be walkable or have no last_Java_frame when in
 560       // thread_in_native
 561       jt->frame_anchor()->make_walkable(jt);
 562       jt->set_thread_state(_thread_in_native);
 563     }
 564   }
 565   notify_vm_shutdown();
 566 }
 567 
 568 void vm_shutdown()
 569 {
 570   vm_perform_shutdown_actions();
 571   os::wait_for_keypress_at_exit();
 572   os::shutdown();
 573 }
 574 
 575 void vm_abort(bool dump_core) {
 576   vm_perform_shutdown_actions();
 577   os::wait_for_keypress_at_exit();
 578 
 579   // Flush stdout and stderr before abort.
 580   fflush(stdout);
 581   fflush(stderr);
 582 
 583   os::abort(dump_core);
 584   ShouldNotReachHere();
 585 }
 586 
 587 void vm_notify_during_shutdown(const char* error, const char* message) {
 588   if (error != NULL) {
 589     tty->print_cr("Error occurred during initialization of VM");
 590     tty->print("%s", error);
 591     if (message != NULL) {
 592       tty->print_cr(": %s", message);
 593     }
 594     else {
 595       tty->cr();
 596     }
 597   }
 598   if (ShowMessageBoxOnError && WizardMode) {
 599     fatal("Error occurred during initialization of VM");
 600   }
 601 }
 602 
 603 void vm_exit_during_initialization(Handle exception) {
 604   tty->print_cr("Error occurred during initialization of VM");
 605   // If there are exceptions on this thread it must be cleared
 606   // first and here. Any future calls to EXCEPTION_MARK requires
 607   // that no pending exceptions exist.
 608   Thread *THREAD = Thread::current();
 609   if (HAS_PENDING_EXCEPTION) {
 610     CLEAR_PENDING_EXCEPTION;
 611   }
 612   java_lang_Throwable::print(exception, tty);
 613   tty->cr();
 614   java_lang_Throwable::print_stack_trace(exception(), tty);
 615   tty->cr();
 616   vm_notify_during_shutdown(NULL, NULL);
 617 
 618   // Failure during initialization, we don't want to dump core
 619   vm_abort(false);
 620 }
 621 
 622 void vm_exit_during_initialization(Symbol* ex, const char* message) {
 623   ResourceMark rm;
 624   vm_notify_during_shutdown(ex->as_C_string(), message);
 625 
 626   // Failure during initialization, we don't want to dump core
 627   vm_abort(false);
 628 }
 629 
 630 void vm_exit_during_initialization(const char* error, const char* message) {
 631   vm_notify_during_shutdown(error, message);
 632 
 633   // Failure during initialization, we don't want to dump core
 634   vm_abort(false);
 635 }
 636 
 637 void vm_shutdown_during_initialization(const char* error, const char* message) {
 638   vm_notify_during_shutdown(error, message);
 639   vm_shutdown();
 640 }
 641 
 642 JDK_Version JDK_Version::_current;
 643 const char* JDK_Version::_runtime_name;
 644 const char* JDK_Version::_runtime_version;
 645 
 646 void JDK_Version::initialize() {
 647   jdk_version_info info;
 648   assert(!_current.is_valid(), "Don't initialize twice");
 649 
 650   void *lib_handle = os::native_java_library();
 651   jdk_version_info_fn_t func = CAST_TO_FN_PTR(jdk_version_info_fn_t,
 652      os::dll_lookup(lib_handle, "JDK_GetVersionInfo0"));
 653 
 654   if (func == NULL) {
 655     // JDK older than 1.6
 656     _current._partially_initialized = true;
 657   } else {
 658     (*func)(&info, sizeof(info));
 659 
 660     int major = JDK_VERSION_MAJOR(info.jdk_version);
 661     int minor = JDK_VERSION_MINOR(info.jdk_version);
 662     int micro = JDK_VERSION_MICRO(info.jdk_version);
 663     int build = JDK_VERSION_BUILD(info.jdk_version);
 664     if (major == 1 && minor > 4) {
 665       // We represent "1.5.0" as "5.0", but 1.4.2 as itself.
 666       major = minor;
 667       minor = micro;
 668       micro = 0;
 669     }
 670     // Incompatible with pre-4243978 JDK.
 671     if (info.pending_list_uses_discovered_field == 0) {
 672       vm_exit_during_initialization(
 673         "Incompatible JDK is not using Reference.discovered field for pending list");
 674     }
 675     _current = JDK_Version(major, minor, micro, info.update_version,
 676                            info.special_update_version, build,
 677                            info.thread_park_blocker == 1,
 678                            info.post_vm_init_hook_enabled == 1);
 679   }
 680 }
 681 
 682 void JDK_Version::fully_initialize(
 683     uint8_t major, uint8_t minor, uint8_t micro, uint8_t update) {
 684   // This is only called when current is less than 1.6 and we've gotten
 685   // far enough in the initialization to determine the exact version.
 686   assert(major < 6, "not needed for JDK version >= 6");
 687   assert(is_partially_initialized(), "must not initialize");
 688   if (major < 5) {
 689     // JDK verison sequence: 1.2.x, 1.3.x, 1.4.x, 5.0.x, 6.0.x, etc.
 690     micro = minor;
 691     minor = major;
 692     major = 1;
 693   }
 694   _current = JDK_Version(major, minor, micro, update);
 695 }
 696 
 697 void JDK_Version_init() {
 698   JDK_Version::initialize();
 699 }
 700 
 701 static int64_t encode_jdk_version(const JDK_Version& v) {
 702   return
 703     ((int64_t)v.major_version()          << (BitsPerByte * 5)) |
 704     ((int64_t)v.minor_version()          << (BitsPerByte * 4)) |
 705     ((int64_t)v.micro_version()          << (BitsPerByte * 3)) |
 706     ((int64_t)v.update_version()         << (BitsPerByte * 2)) |
 707     ((int64_t)v.special_update_version() << (BitsPerByte * 1)) |
 708     ((int64_t)v.build_number()           << (BitsPerByte * 0));
 709 }
 710 
 711 int JDK_Version::compare(const JDK_Version& other) const {
 712   assert(is_valid() && other.is_valid(), "Invalid version (uninitialized?)");
 713   if (!is_partially_initialized() && other.is_partially_initialized()) {
 714     return -(other.compare(*this)); // flip the comparators
 715   }
 716   assert(!other.is_partially_initialized(), "Not initialized yet");
 717   if (is_partially_initialized()) {
 718     assert(other.major_version() >= 6,
 719            "Invalid JDK version comparison during initialization");
 720     return -1;
 721   } else {
 722     uint64_t e = encode_jdk_version(*this);
 723     uint64_t o = encode_jdk_version(other);
 724     return (e > o) ? 1 : ((e == o) ? 0 : -1);
 725   }
 726 }
 727 
 728 void JDK_Version::to_string(char* buffer, size_t buflen) const {
 729   assert(buffer && buflen > 0, "call with useful buffer");
 730   size_t index = 0;
 731 
 732   if (!is_valid()) {
 733     jio_snprintf(buffer, buflen, "%s", "(uninitialized)");
 734   } else if (is_partially_initialized()) {
 735     jio_snprintf(buffer, buflen, "%s", "(uninitialized) pre-1.6.0");
 736   } else {
 737     int rc = jio_snprintf(
 738         &buffer[index], buflen - index, "%d.%d", _major, _minor);
 739     if (rc == -1) return;
 740     index += rc;
 741     if (_micro > 0) {
 742       rc = jio_snprintf(&buffer[index], buflen - index, ".%d", _micro);
 743     }
 744     if (_update > 0) {
 745       rc = jio_snprintf(&buffer[index], buflen - index, "_%02d", _update);
 746       if (rc == -1) return;
 747       index += rc;
 748     }
 749     if (_special > 0) {
 750       rc = jio_snprintf(&buffer[index], buflen - index, "%c", _special);
 751       if (rc == -1) return;
 752       index += rc;
 753     }
 754     if (_build > 0) {
 755       rc = jio_snprintf(&buffer[index], buflen - index, "-b%02d", _build);
 756       if (rc == -1) return;
 757       index += rc;
 758     }
 759   }
 760 }