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 #include "memory/oopFactory.hpp"
  35 #include "memory/universe.hpp"
  36 #include "oops/constantPool.hpp"
  37 #include "oops/generateOopMap.hpp"
  38 #include "oops/instanceKlass.hpp"
  39 #include "oops/instanceOop.hpp"
  40 #include "oops/method.hpp"
  41 #include "oops/objArrayOop.hpp"
  42 #include "oops/oop.inline.hpp"
  43 #include "oops/symbol.hpp"
  44 #include "prims/jvmtiExport.hpp"
  45 #include "runtime/arguments.hpp"
  46 #include "runtime/biasedLocking.hpp"
  47 #include "runtime/compilationPolicy.hpp"
  48 #include "runtime/fprofiler.hpp"
  49 #include "runtime/init.hpp"
  50 #include "runtime/interfaceSupport.hpp"
  51 #include "runtime/java.hpp"
  52 #include "runtime/memprofiler.hpp"
  53 #include "runtime/sharedRuntime.hpp"
  54 #include "runtime/statSampler.hpp"
  55 #include "runtime/sweeper.hpp"
  56 #include "runtime/task.hpp"
  57 #include "runtime/thread.inline.hpp"
  58 #include "runtime/timer.hpp"
  59 #include "runtime/vm_operations.hpp"
  60 #include "services/memTracker.hpp"
  61 #include "trace/tracing.hpp"
  62 #include "utilities/dtrace.hpp"
  63 #include "utilities/globalDefinitions.hpp"
  64 #include "utilities/histogram.hpp"
  65 #include "utilities/macros.hpp"
  66 #include "utilities/vmError.hpp"
  67 #if INCLUDE_ALL_GCS
  68 #include "gc/cms/concurrentMarkSweepThread.hpp"
  69 #include "gc/parallel/psScavenge.hpp"
  70 #endif // INCLUDE_ALL_GCS
  71 #ifdef COMPILER1
  72 #include "c1/c1_Compiler.hpp"
  73 #include "c1/c1_Runtime1.hpp"
  74 #endif
  75 #ifdef COMPILER2
  76 #include "code/compiledIC.hpp"
  77 #include "compiler/methodLiveness.hpp"
  78 #include "opto/compile.hpp"
  79 #include "opto/indexSet.hpp"
  80 #include "opto/runtime.hpp"
  81 #endif
  82 
  83 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  84 
  85 GrowableArray<Method*>* collected_profiled_methods;
  86 
  87 int compare_methods(Method** a, Method** b) {
  88   // %%% there can be 32-bit overflow here
  89   return ((*b)->invocation_count() + (*b)->compiled_invocation_count())
  90        - ((*a)->invocation_count() + (*a)->compiled_invocation_count());
  91 }
  92 
  93 void collect_profiled_methods(Method* m) {
  94   Thread* thread = Thread::current();
  95   // This HandleMark prevents a huge amount of handles from being added
  96   // to the metadata_handles() array on the thread.
  97   HandleMark hm(thread);
  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     ClassLoaderDataGraph::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 MethodOop Invocation Counters (cutoff = %d):", 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     nmethod::print_statistics();
 240   }
 241 #endif /* COMPILER1 */
 242 
 243 #ifdef COMPILER2
 244   if ((PrintOptoStatistics || LogVMOutput || LogCompilation) && UseCompiler) {
 245     FlagSetting fs(DisplayVMOutput, DisplayVMOutput && PrintOptoStatistics);
 246     Compile::print_statistics();
 247 #ifndef COMPILER1
 248     Deoptimization::print_statistics();
 249     nmethod::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 #endif // COMPILER2
 268   if (CountCompiledCalls) {
 269     print_method_invocation_histogram();
 270   }
 271 
 272   print_method_profiling_data();
 273 
 274   if (TimeCompilationPolicy) {
 275     CompilationPolicy::policy()->print_time();
 276   }
 277   if (TimeOopMap) {
 278     GenerateOopMap::print_time();
 279   }
 280   if (ProfilerCheckIntervals) {
 281     PeriodicTask::print_intervals();
 282   }
 283   if (PrintSymbolTableSizeHistogram) {
 284     SymbolTable::print_histogram();
 285   }
 286   if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
 287     BytecodeCounter::print();
 288   }
 289   if (PrintBytecodePairHistogram) {
 290     BytecodePairHistogram::print();
 291   }
 292 
 293   if (PrintCodeCache) {
 294     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 295     CodeCache::print();
 296   }
 297 
 298   if (PrintMethodFlushingStatistics) {
 299     NMethodSweeper::print();
 300   }
 301 
 302   if (PrintCodeCache2) {
 303     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 304     CodeCache::print_internals();
 305   }
 306 
 307   if (PrintClassStatistics) {
 308     SystemDictionary::print_class_statistics();
 309   }
 310   if (PrintMethodStatistics) {
 311     SystemDictionary::print_method_statistics();
 312   }
 313 
 314   if (PrintVtableStats) {
 315     klassVtable::print_statistics();
 316     klassItable::print_statistics();
 317   }
 318   if (VerifyOops) {
 319     tty->print_cr("+VerifyOops count: %d", StubRoutines::verify_oop_count());
 320   }
 321 
 322   print_bytecode_count();
 323   if (PrintMallocStatistics) {
 324     tty->print("allocation stats: ");
 325     alloc_stats.print();
 326     tty->cr();
 327   }
 328 
 329   if (PrintSystemDictionaryAtExit) {
 330     SystemDictionary::print();
 331   }
 332 
 333   if (PrintBiasedLockingStatistics) {
 334     BiasedLocking::print_counters();
 335   }
 336 
 337 #ifdef ENABLE_ZAP_DEAD_LOCALS
 338 #ifdef COMPILER2
 339   if (ZapDeadCompiledLocals) {
 340     tty->print_cr("Compile::CompiledZap_count = %d", Compile::CompiledZap_count);
 341     tty->print_cr("OptoRuntime::ZapDeadCompiledLocals_count = %d", OptoRuntime::ZapDeadCompiledLocals_count);
 342   }
 343 #endif // COMPILER2
 344 #endif // ENABLE_ZAP_DEAD_LOCALS
 345   // Native memory tracking data
 346   if (PrintNMTStatistics) {
 347     MemTracker::final_report(tty);
 348   }
 349 }
 350 
 351 #else // PRODUCT MODE STATISTICS
 352 
 353 void print_statistics() {
 354 
 355   if (PrintMethodData) {
 356     print_method_profiling_data();
 357   }
 358 
 359   if (CITime) {
 360     CompileBroker::print_times();
 361   }
 362 
 363   if (PrintCodeCache) {
 364     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 365     CodeCache::print();
 366   }
 367 
 368   if (PrintMethodFlushingStatistics) {
 369     NMethodSweeper::print();
 370   }
 371 
 372 #ifdef COMPILER2
 373   if (PrintPreciseBiasedLockingStatistics || PrintPreciseRTMLockingStatistics) {
 374     OptoRuntime::print_named_counters();
 375   }
 376 #endif
 377   if (PrintBiasedLockingStatistics) {
 378     BiasedLocking::print_counters();
 379   }
 380 
 381   // Native memory tracking data
 382   if (PrintNMTStatistics) {
 383     MemTracker::final_report(tty);
 384   }
 385 }
 386 
 387 #endif
 388 
 389 // Note: before_exit() can be executed only once, if more than one threads
 390 //       are trying to shutdown the VM at the same time, only one thread
 391 //       can run before_exit() and all other threads must wait.
 392 void before_exit(JavaThread * thread) {
 393   #define BEFORE_EXIT_NOT_RUN 0
 394   #define BEFORE_EXIT_RUNNING 1
 395   #define BEFORE_EXIT_DONE    2
 396   static jint volatile _before_exit_status = BEFORE_EXIT_NOT_RUN;
 397 
 398   // Note: don't use a Mutex to guard the entire before_exit(), as
 399   // JVMTI post_thread_end_event and post_vm_death_event will run native code.
 400   // A CAS or OSMutex would work just fine but then we need to manipulate
 401   // thread state for Safepoint. Here we use Monitor wait() and notify_all()
 402   // for synchronization.
 403   { MutexLocker ml(BeforeExit_lock);
 404     switch (_before_exit_status) {
 405     case BEFORE_EXIT_NOT_RUN:
 406       _before_exit_status = BEFORE_EXIT_RUNNING;
 407       break;
 408     case BEFORE_EXIT_RUNNING:
 409       while (_before_exit_status == BEFORE_EXIT_RUNNING) {
 410         BeforeExit_lock->wait();
 411       }
 412       assert(_before_exit_status == BEFORE_EXIT_DONE, "invalid state");
 413       return;
 414     case BEFORE_EXIT_DONE:
 415       return;
 416     }
 417   }
 418 
 419   // Hang forever on exit if we're reporting an error.
 420   if (ShowMessageBoxOnError && is_error_reported()) {
 421     os::infinite_sleep();
 422   }
 423 
 424   // Stop the WatcherThread. We do this before disenrolling various
 425   // PeriodicTasks to reduce the likelihood of races.
 426   if (PeriodicTask::num_tasks() > 0) {
 427     WatcherThread::stop();
 428   }
 429 
 430   // Print statistics gathered (profiling ...)
 431   if (Arguments::has_profile()) {
 432     FlatProfiler::disengage();
 433     FlatProfiler::print(10);
 434   }
 435 
 436   // shut down the StatSampler task
 437   StatSampler::disengage();
 438   StatSampler::destroy();
 439 
 440   // Stop concurrent GC threads
 441   Universe::heap()->stop();
 442 
 443   // Print GC/heap related information.
 444   if (PrintGCDetails) {
 445     Universe::print();
 446     AdaptiveSizePolicyOutput(0);
 447     if (Verbose) {
 448       ClassLoaderDataGraph::dump_on(gclog_or_tty);
 449     }
 450   }
 451 
 452   if (PrintBytecodeHistogram) {
 453     BytecodeHistogram::print();
 454   }
 455 
 456   if (JvmtiExport::should_post_thread_life()) {
 457     JvmtiExport::post_thread_end(thread);
 458   }
 459 
 460 
 461   EventThreadEnd event;
 462   if (event.should_commit()) {
 463       event.set_javalangthread(java_lang_Thread::thread_id(thread->threadObj()));
 464       event.commit();
 465   }
 466 
 467   // Always call even when there are not JVMTI environments yet, since environments
 468   // may be attached late and JVMTI must track phases of VM execution
 469   JvmtiExport::post_vm_death();
 470   Threads::shutdown_vm_agents();
 471 
 472   // Terminate the signal thread
 473   // Note: we don't wait until it actually dies.
 474   os::terminate_signal_thread();
 475 
 476   print_statistics();
 477   Universe::heap()->print_tracing_info();
 478 
 479   { MutexLocker ml(BeforeExit_lock);
 480     _before_exit_status = BEFORE_EXIT_DONE;
 481     BeforeExit_lock->notify_all();
 482   }
 483 
 484   if (VerifyStringTableAtExit) {
 485     int fail_cnt = 0;
 486     {
 487       MutexLocker ml(StringTable_lock);
 488       fail_cnt = StringTable::verify_and_compare_entries();
 489     }
 490 
 491     if (fail_cnt != 0) {
 492       tty->print_cr("ERROR: fail_cnt=%d", fail_cnt);
 493       guarantee(fail_cnt == 0, "unexpected StringTable verification failures");
 494     }
 495   }
 496 
 497   #undef BEFORE_EXIT_NOT_RUN
 498   #undef BEFORE_EXIT_RUNNING
 499   #undef BEFORE_EXIT_DONE
 500 }
 501 
 502 void vm_exit(int code) {
 503   Thread* thread = ThreadLocalStorage::is_initialized() ?
 504     ThreadLocalStorage::get_thread_slow() : NULL;
 505   if (thread == NULL) {
 506     // we have serious problems -- just exit
 507     vm_direct_exit(code);
 508   }
 509 
 510   if (VMThread::vm_thread() != NULL) {
 511     // Fire off a VM_Exit operation to bring VM to a safepoint and exit
 512     VM_Exit op(code);
 513     if (thread->is_Java_thread())
 514       ((JavaThread*)thread)->set_thread_state(_thread_in_vm);
 515     VMThread::execute(&op);
 516     // should never reach here; but in case something wrong with VM Thread.
 517     vm_direct_exit(code);
 518   } else {
 519     // VM thread is gone, just exit
 520     vm_direct_exit(code);
 521   }
 522   ShouldNotReachHere();
 523 }
 524 
 525 void notify_vm_shutdown() {
 526   // For now, just a dtrace probe.
 527   HOTSPOT_VM_SHUTDOWN();
 528   HS_DTRACE_WORKAROUND_TAIL_CALL_BUG();
 529 }
 530 
 531 void vm_direct_exit(int code) {
 532   notify_vm_shutdown();
 533   os::wait_for_keypress_at_exit();
 534   os::exit(code);
 535 }
 536 
 537 void vm_perform_shutdown_actions() {
 538   // Warning: do not call 'exit_globals()' here. All threads are still running.
 539   // Calling 'exit_globals()' will disable thread-local-storage and cause all
 540   // kinds of assertions to trigger in debug mode.
 541   if (is_init_completed()) {
 542     Thread* thread = ThreadLocalStorage::is_initialized() ?
 543                      ThreadLocalStorage::get_thread_slow() : NULL;
 544     if (thread != NULL && thread->is_Java_thread()) {
 545       // We are leaving the VM, set state to native (in case any OS exit
 546       // handlers call back to the VM)
 547       JavaThread* jt = (JavaThread*)thread;
 548       // Must always be walkable or have no last_Java_frame when in
 549       // thread_in_native
 550       jt->frame_anchor()->make_walkable(jt);
 551       jt->set_thread_state(_thread_in_native);
 552     }
 553   }
 554   notify_vm_shutdown();
 555 }
 556 
 557 void vm_shutdown()
 558 {
 559   vm_perform_shutdown_actions();
 560   os::wait_for_keypress_at_exit();
 561   os::shutdown();
 562 }
 563 
 564 void vm_abort(bool dump_core) {
 565   vm_perform_shutdown_actions();
 566   os::wait_for_keypress_at_exit();
 567   os::abort(dump_core);
 568   ShouldNotReachHere();
 569 }
 570 
 571 void vm_notify_during_shutdown(const char* error, const char* message) {
 572   if (error != NULL) {
 573     tty->print_cr("Error occurred during initialization of VM");
 574     tty->print("%s", error);
 575     if (message != NULL) {
 576       tty->print_cr(": %s", message);
 577     }
 578     else {
 579       tty->cr();
 580     }
 581   }
 582   if (ShowMessageBoxOnError && WizardMode) {
 583     fatal("Error occurred during initialization of VM");
 584   }
 585 }
 586 
 587 void vm_exit_during_initialization(Handle exception) {
 588   tty->print_cr("Error occurred during initialization of VM");
 589   // If there are exceptions on this thread it must be cleared
 590   // first and here. Any future calls to EXCEPTION_MARK requires
 591   // that no pending exceptions exist.
 592   Thread *THREAD = Thread::current();
 593   if (HAS_PENDING_EXCEPTION) {
 594     CLEAR_PENDING_EXCEPTION;
 595   }
 596   java_lang_Throwable::print(exception, tty);
 597   tty->cr();
 598   java_lang_Throwable::print_stack_trace(exception(), tty);
 599   tty->cr();
 600   vm_notify_during_shutdown(NULL, NULL);
 601 
 602   // Failure during initialization, we don't want to dump core
 603   vm_abort(false);
 604 }
 605 
 606 void vm_exit_during_initialization(Symbol* ex, const char* message) {
 607   ResourceMark rm;
 608   vm_notify_during_shutdown(ex->as_C_string(), message);
 609 
 610   // Failure during initialization, we don't want to dump core
 611   vm_abort(false);
 612 }
 613 
 614 void vm_exit_during_initialization(const char* error, const char* message) {
 615   vm_notify_during_shutdown(error, message);
 616 
 617   // Failure during initialization, we don't want to dump core
 618   vm_abort(false);
 619 }
 620 
 621 void vm_shutdown_during_initialization(const char* error, const char* message) {
 622   vm_notify_during_shutdown(error, message);
 623   vm_shutdown();
 624 }
 625 
 626 JDK_Version JDK_Version::_current;
 627 const char* JDK_Version::_runtime_name;
 628 const char* JDK_Version::_runtime_version;
 629 
 630 void JDK_Version::initialize() {
 631   jdk_version_info info;
 632   assert(!_current.is_valid(), "Don't initialize twice");
 633 
 634   void *lib_handle = os::native_java_library();
 635   jdk_version_info_fn_t func = CAST_TO_FN_PTR(jdk_version_info_fn_t,
 636      os::dll_lookup(lib_handle, "JDK_GetVersionInfo0"));
 637 
 638   if (func == NULL) {
 639     // JDK older than 1.6
 640     _current._partially_initialized = true;
 641   } else {
 642     (*func)(&info, sizeof(info));
 643 
 644     int major = JDK_VERSION_MAJOR(info.jdk_version);
 645     int minor = JDK_VERSION_MINOR(info.jdk_version);
 646     int security = JDK_VERSION_SECURITY(info.jdk_version);
 647     int build = JDK_VERSION_BUILD(info.jdk_version);
 648 
 649     // Incompatible with pre-4243978 JDK.
 650     if (info.pending_list_uses_discovered_field == 0) {
 651       vm_exit_during_initialization(
 652         "Incompatible JDK is not using Reference.discovered field for pending list");
 653     }
 654     _current = JDK_Version(major, minor, security, info.update_version,
 655                            info.special_update_version, build,
 656                            info.thread_park_blocker == 1,
 657                            info.post_vm_init_hook_enabled == 1);
 658   }
 659 }
 660 
 661 void JDK_Version::fully_initialize(
 662     uint8_t major, uint8_t minor, uint8_t security, uint8_t update) {
 663   // This is only called when current is less than 1.6 and we've gotten
 664   // far enough in the initialization to determine the exact version.
 665   assert(major < 6, "not needed for JDK version >= 6");
 666   assert(is_partially_initialized(), "must not initialize");
 667   if (major < 5) {
 668     // JDK verison sequence: 1.2.x, 1.3.x, 1.4.x, 5.0.x, 6.0.x, etc.
 669     security = minor;
 670     minor = major;
 671     major = 1;
 672   }
 673   _current = JDK_Version(major, minor, security, update);
 674 }
 675 
 676 void JDK_Version_init() {
 677   JDK_Version::initialize();
 678 }
 679 
 680 static int64_t encode_jdk_version(const JDK_Version& v) {
 681   return
 682     ((int64_t)v.major_version()          << (BitsPerByte * 5)) |
 683     ((int64_t)v.minor_version()          << (BitsPerByte * 4)) |
 684     ((int64_t)v.security_version()       << (BitsPerByte * 3)) |
 685     ((int64_t)v.update_version()         << (BitsPerByte * 2)) |
 686     ((int64_t)v.special_update_version() << (BitsPerByte * 1)) |
 687     ((int64_t)v.build_number()           << (BitsPerByte * 0));
 688 }
 689 
 690 int JDK_Version::compare(const JDK_Version& other) const {
 691   assert(is_valid() && other.is_valid(), "Invalid version (uninitialized?)");
 692   if (!is_partially_initialized() && other.is_partially_initialized()) {
 693     return -(other.compare(*this)); // flip the comparators
 694   }
 695   assert(!other.is_partially_initialized(), "Not initialized yet");
 696   if (is_partially_initialized()) {
 697     assert(other.major_version() >= 6,
 698            "Invalid JDK version comparison during initialization");
 699     return -1;
 700   } else {
 701     uint64_t e = encode_jdk_version(*this);
 702     uint64_t o = encode_jdk_version(other);
 703     return (e > o) ? 1 : ((e == o) ? 0 : -1);
 704   }
 705 }
 706 
 707 void JDK_Version::to_string(char* buffer, size_t buflen) const {
 708   assert(buffer && buflen > 0, "call with useful buffer");
 709   size_t index = 0;
 710 
 711   if (!is_valid()) {
 712     jio_snprintf(buffer, buflen, "%s", "(uninitialized)");
 713   } else if (is_partially_initialized()) {
 714     jio_snprintf(buffer, buflen, "%s", "(uninitialized) pre-1.6.0");
 715   } else {
 716     int rc = jio_snprintf(
 717         &buffer[index], buflen - index, "%d.%d", _major, _minor);
 718     if (rc == -1) return;
 719     index += rc;
 720     if (_security > 0) {
 721       rc = jio_snprintf(&buffer[index], buflen - index, ".%d", _security);
 722     }
 723     if (_update > 0) {
 724       rc = jio_snprintf(&buffer[index], buflen - index, "_%02d", _update);
 725       if (rc == -1) return;
 726       index += rc;
 727     }
 728     if (_special > 0) {
 729       rc = jio_snprintf(&buffer[index], buflen - index, "%c", _special);
 730       if (rc == -1) return;
 731       index += rc;
 732     }
 733     if (_build > 0) {
 734       rc = jio_snprintf(&buffer[index], buflen - index, "-b%02d", _build);
 735       if (rc == -1) return;
 736       index += rc;
 737     }
 738   }
 739 }