java.cpp revision 9099:115188e14c15 
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
83GrowableArray<Method*>* collected_profiled_methods;
84
85int compare_methods(Method** a, Method** b) {
86  // %%% there can be 32-bit overflow here
87  return ((*b)->invocation_count() + (*b)->compiled_invocation_count())
88       - ((*a)->invocation_count() + (*a)->compiled_invocation_count());
89}
90
91void collect_profiled_methods(Method* m) {
92  Thread* thread = Thread::current();
93  // This HandleMark prevents a huge amount of handles from being added
94  // to the metadata_handles() array on the thread.
95  HandleMark hm(thread);
96  methodHandle mh(thread, m);
97  if ((m->method_data() != NULL) &&
98      (PrintMethodData || CompilerOracle::should_print(mh))) {
99    collected_profiled_methods->push(m);
100  }
101}
102
103void print_method_profiling_data() {
104  if (ProfileInterpreter COMPILER1_PRESENT(|| C1UpdateMethodData) &&
105     (PrintMethodData || CompilerOracle::should_print_methods())) {
106    ResourceMark rm;
107    HandleMark hm;
108    collected_profiled_methods = new GrowableArray<Method*>(1024);
109    ClassLoaderDataGraph::methods_do(collect_profiled_methods);
110    collected_profiled_methods->sort(&compare_methods);
111
112    int count = collected_profiled_methods->length();
113    int total_size = 0;
114    if (count > 0) {
115      for (int index = 0; index < count; index++) {
116        Method* m = collected_profiled_methods->at(index);
117        ttyLocker ttyl;
118        tty->print_cr("------------------------------------------------------------------------");
119        m->print_invocation_count();
120        tty->print_cr("  mdo size: %d bytes", m->method_data()->size_in_bytes());
121        tty->cr();
122        // Dump data on parameters if any
123        if (m->method_data() != NULL && m->method_data()->parameters_type_data() != NULL) {
124          tty->fill_to(2);
125          m->method_data()->parameters_type_data()->print_data_on(tty);
126        }
127        m->print_codes();
128        total_size += m->method_data()->size_in_bytes();
129      }
130      tty->print_cr("------------------------------------------------------------------------");
131      tty->print_cr("Total MDO size: %d bytes", total_size);
132    }
133  }
134}
135
136
137#ifndef PRODUCT
138
139// Statistics printing (method invocation histogram)
140
141GrowableArray<Method*>* collected_invoked_methods;
142
143void collect_invoked_methods(Method* m) {
144  if (m->invocation_count() + m->compiled_invocation_count() >= 1 ) {
145    collected_invoked_methods->push(m);
146  }
147}
148
149
150
151
152void print_method_invocation_histogram() {
153  ResourceMark rm;
154  HandleMark hm;
155  collected_invoked_methods = new GrowableArray<Method*>(1024);
156  SystemDictionary::methods_do(collect_invoked_methods);
157  collected_invoked_methods->sort(&compare_methods);
158  //
159  tty->cr();
160  tty->print_cr("Histogram Over MethodOop Invocation Counters (cutoff = " INTX_FORMAT "):", MethodHistogramCutoff);
161  tty->cr();
162  tty->print_cr("____Count_(I+C)____Method________________________Module_________________");
163  unsigned total = 0, int_total = 0, comp_total = 0, static_total = 0, final_total = 0,
164      synch_total = 0, nativ_total = 0, acces_total = 0;
165  for (int index = 0; index < collected_invoked_methods->length(); index++) {
166    Method* m = collected_invoked_methods->at(index);
167    int c = m->invocation_count() + m->compiled_invocation_count();
168    if (c >= MethodHistogramCutoff) m->print_invocation_count();
169    int_total  += m->invocation_count();
170    comp_total += m->compiled_invocation_count();
171    if (m->is_final())        final_total  += c;
172    if (m->is_static())       static_total += c;
173    if (m->is_synchronized()) synch_total  += c;
174    if (m->is_native())       nativ_total  += c;
175    if (m->is_accessor())     acces_total  += c;
176  }
177  tty->cr();
178  total = int_total + comp_total;
179  tty->print_cr("Invocations summary:");
180  tty->print_cr("\t%9d (%4.1f%%) interpreted",  int_total,    100.0 * int_total    / total);
181  tty->print_cr("\t%9d (%4.1f%%) compiled",     comp_total,   100.0 * comp_total   / total);
182  tty->print_cr("\t%9d (100%%)  total",         total);
183  tty->print_cr("\t%9d (%4.1f%%) synchronized", synch_total,  100.0 * synch_total  / total);
184  tty->print_cr("\t%9d (%4.1f%%) final",        final_total,  100.0 * final_total  / total);
185  tty->print_cr("\t%9d (%4.1f%%) static",       static_total, 100.0 * static_total / total);
186  tty->print_cr("\t%9d (%4.1f%%) native",       nativ_total,  100.0 * nativ_total  / total);
187  tty->print_cr("\t%9d (%4.1f%%) accessor",     acces_total,  100.0 * acces_total  / total);
188  tty->cr();
189  SharedRuntime::print_call_statistics(comp_total);
190}
191
192void print_bytecode_count() {
193  if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
194    tty->print_cr("[BytecodeCounter::counter_value = %d]", BytecodeCounter::counter_value());
195  }
196}
197
198AllocStats alloc_stats;
199
200
201
202// General statistics printing (profiling ...)
203void print_statistics() {
204#ifdef ASSERT
205
206  if (CountRuntimeCalls) {
207    extern Histogram *RuntimeHistogram;
208    RuntimeHistogram->print();
209  }
210
211  if (CountJNICalls) {
212    extern Histogram *JNIHistogram;
213    JNIHistogram->print();
214  }
215
216  if (CountJVMCalls) {
217    extern Histogram *JVMHistogram;
218    JVMHistogram->print();
219  }
220
221#endif
222
223  if (MemProfiling) {
224    MemProfiler::disengage();
225  }
226
227  if (CITime) {
228    CompileBroker::print_times();
229  }
230
231#ifdef COMPILER1
232  if ((PrintC1Statistics || LogVMOutput || LogCompilation) && UseCompiler) {
233    FlagSetting fs(DisplayVMOutput, DisplayVMOutput && PrintC1Statistics);
234    Runtime1::print_statistics();
235    Deoptimization::print_statistics();
236    SharedRuntime::print_statistics();
237    nmethod::print_statistics();
238  }
239#endif /* COMPILER1 */
240
241#ifdef COMPILER2
242  if ((PrintOptoStatistics || LogVMOutput || LogCompilation) && UseCompiler) {
243    FlagSetting fs(DisplayVMOutput, DisplayVMOutput && PrintOptoStatistics);
244    Compile::print_statistics();
245#ifndef COMPILER1
246    Deoptimization::print_statistics();
247    nmethod::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#endif // COMPILER2
266  if (CountCompiledCalls) {
267    print_method_invocation_histogram();
268  }
269
270  print_method_profiling_data();
271
272  if (TimeCompilationPolicy) {
273    CompilationPolicy::policy()->print_time();
274  }
275  if (TimeOopMap) {
276    GenerateOopMap::print_time();
277  }
278  if (ProfilerCheckIntervals) {
279    PeriodicTask::print_intervals();
280  }
281  if (PrintSymbolTableSizeHistogram) {
282    SymbolTable::print_histogram();
283  }
284  if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
285    BytecodeCounter::print();
286  }
287  if (PrintBytecodePairHistogram) {
288    BytecodePairHistogram::print();
289  }
290
291  if (PrintCodeCache) {
292    MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
293    CodeCache::print();
294  }
295
296  if (PrintMethodFlushingStatistics) {
297    NMethodSweeper::print();
298  }
299
300  if (PrintCodeCache2) {
301    MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
302    CodeCache::print_internals();
303  }
304
305  if (PrintVtableStats) {
306    klassVtable::print_statistics();
307    klassItable::print_statistics();
308  }
309  if (VerifyOops) {
310    tty->print_cr("+VerifyOops count: %d", StubRoutines::verify_oop_count());
311  }
312
313  print_bytecode_count();
314  if (PrintMallocStatistics) {
315    tty->print("allocation stats: ");
316    alloc_stats.print();
317    tty->cr();
318  }
319
320  if (PrintSystemDictionaryAtExit) {
321    SystemDictionary::print();
322  }
323
324  if (LogTouchedMethods && PrintTouchedMethodsAtExit) {
325    Method::print_touched_methods(tty);
326  }
327
328  if (PrintBiasedLockingStatistics) {
329    BiasedLocking::print_counters();
330  }
331
332  // Native memory tracking data
333  if (PrintNMTStatistics) {
334    MemTracker::final_report(tty);
335  }
336}
337
338#else // PRODUCT MODE STATISTICS
339
340void print_statistics() {
341
342  if (PrintMethodData) {
343    print_method_profiling_data();
344  }
345
346  if (CITime) {
347    CompileBroker::print_times();
348  }
349
350  if (PrintCodeCache) {
351    MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
352    CodeCache::print();
353  }
354
355  if (PrintMethodFlushingStatistics) {
356    NMethodSweeper::print();
357  }
358
359#ifdef COMPILER2
360  if (PrintPreciseBiasedLockingStatistics || PrintPreciseRTMLockingStatistics) {
361    OptoRuntime::print_named_counters();
362  }
363#endif
364  if (PrintBiasedLockingStatistics) {
365    BiasedLocking::print_counters();
366  }
367
368  // Native memory tracking data
369  if (PrintNMTStatistics) {
370    MemTracker::final_report(tty);
371  }
372
373  if (LogTouchedMethods && PrintTouchedMethodsAtExit) {
374    Method::print_touched_methods(tty);
375  }
376}
377
378#endif
379
380// Note: before_exit() can be executed only once, if more than one threads
381//       are trying to shutdown the VM at the same time, only one thread
382//       can run before_exit() and all other threads must wait.
383void before_exit(JavaThread * thread) {
384  #define BEFORE_EXIT_NOT_RUN 0
385  #define BEFORE_EXIT_RUNNING 1
386  #define BEFORE_EXIT_DONE    2
387  static jint volatile _before_exit_status = BEFORE_EXIT_NOT_RUN;
388
389  // Note: don't use a Mutex to guard the entire before_exit(), as
390  // JVMTI post_thread_end_event and post_vm_death_event will run native code.
391  // A CAS or OSMutex would work just fine but then we need to manipulate
392  // thread state for Safepoint. Here we use Monitor wait() and notify_all()
393  // for synchronization.
394  { MutexLocker ml(BeforeExit_lock);
395    switch (_before_exit_status) {
396    case BEFORE_EXIT_NOT_RUN:
397      _before_exit_status = BEFORE_EXIT_RUNNING;
398      break;
399    case BEFORE_EXIT_RUNNING:
400      while (_before_exit_status == BEFORE_EXIT_RUNNING) {
401        BeforeExit_lock->wait();
402      }
403      assert(_before_exit_status == BEFORE_EXIT_DONE, "invalid state");
404      return;
405    case BEFORE_EXIT_DONE:
406      return;
407    }
408  }
409
410  // Hang forever on exit if we're reporting an error.
411  if (ShowMessageBoxOnError && is_error_reported()) {
412    os::infinite_sleep();
413  }
414
415  // Stop the WatcherThread. We do this before disenrolling various
416  // PeriodicTasks to reduce the likelihood of races.
417  if (PeriodicTask::num_tasks() > 0) {
418    WatcherThread::stop();
419  }
420
421  // Print statistics gathered (profiling ...)
422  if (Arguments::has_profile()) {
423    FlatProfiler::disengage();
424    FlatProfiler::print(10);
425  }
426
427  // shut down the StatSampler task
428  StatSampler::disengage();
429  StatSampler::destroy();
430
431  // Stop concurrent GC threads
432  Universe::heap()->stop();
433
434  // Print GC/heap related information.
435  if (PrintGCDetails) {
436    Universe::print();
437    AdaptiveSizePolicyOutput(0);
438    if (Verbose) {
439      ClassLoaderDataGraph::dump_on(gclog_or_tty);
440    }
441  }
442
443  if (PrintBytecodeHistogram) {
444    BytecodeHistogram::print();
445  }
446
447  if (JvmtiExport::should_post_thread_life()) {
448    JvmtiExport::post_thread_end(thread);
449  }
450
451
452  EventThreadEnd event;
453  if (event.should_commit()) {
454      event.set_javalangthread(java_lang_Thread::thread_id(thread->threadObj()));
455      event.commit();
456  }
457
458  // Always call even when there are not JVMTI environments yet, since environments
459  // may be attached late and JVMTI must track phases of VM execution
460  JvmtiExport::post_vm_death();
461  Threads::shutdown_vm_agents();
462
463  // Terminate the signal thread
464  // Note: we don't wait until it actually dies.
465  os::terminate_signal_thread();
466
467  print_statistics();
468  Universe::heap()->print_tracing_info();
469
470  { MutexLocker ml(BeforeExit_lock);
471    _before_exit_status = BEFORE_EXIT_DONE;
472    BeforeExit_lock->notify_all();
473  }
474
475  if (VerifyStringTableAtExit) {
476    int fail_cnt = 0;
477    {
478      MutexLocker ml(StringTable_lock);
479      fail_cnt = StringTable::verify_and_compare_entries();
480    }
481
482    if (fail_cnt != 0) {
483      tty->print_cr("ERROR: fail_cnt=%d", fail_cnt);
484      guarantee(fail_cnt == 0, "unexpected StringTable verification failures");
485    }
486  }
487
488  #undef BEFORE_EXIT_NOT_RUN
489  #undef BEFORE_EXIT_RUNNING
490  #undef BEFORE_EXIT_DONE
491}
492
493void vm_exit(int code) {
494  Thread* thread = ThreadLocalStorage::is_initialized() ?
495    ThreadLocalStorage::get_thread_slow() : NULL;
496  if (thread == NULL) {
497    // we have serious problems -- just exit
498    vm_direct_exit(code);
499  }
500
501  if (VMThread::vm_thread() != NULL) {
502    // Fire off a VM_Exit operation to bring VM to a safepoint and exit
503    VM_Exit op(code);
504    if (thread->is_Java_thread())
505      ((JavaThread*)thread)->set_thread_state(_thread_in_vm);
506    VMThread::execute(&op);
507    // should never reach here; but in case something wrong with VM Thread.
508    vm_direct_exit(code);
509  } else {
510    // VM thread is gone, just exit
511    vm_direct_exit(code);
512  }
513  ShouldNotReachHere();
514}
515
516void notify_vm_shutdown() {
517  // For now, just a dtrace probe.
518  HOTSPOT_VM_SHUTDOWN();
519  HS_DTRACE_WORKAROUND_TAIL_CALL_BUG();
520}
521
522void vm_direct_exit(int code) {
523  notify_vm_shutdown();
524  os::wait_for_keypress_at_exit();
525  os::exit(code);
526}
527
528void vm_perform_shutdown_actions() {
529  // Warning: do not call 'exit_globals()' here. All threads are still running.
530  // Calling 'exit_globals()' will disable thread-local-storage and cause all
531  // kinds of assertions to trigger in debug mode.
532  if (is_init_completed()) {
533    Thread* thread = ThreadLocalStorage::is_initialized() ?
534                     ThreadLocalStorage::get_thread_slow() : NULL;
535    if (thread != NULL && thread->is_Java_thread()) {
536      // We are leaving the VM, set state to native (in case any OS exit
537      // handlers call back to the VM)
538      JavaThread* jt = (JavaThread*)thread;
539      // Must always be walkable or have no last_Java_frame when in
540      // thread_in_native
541      jt->frame_anchor()->make_walkable(jt);
542      jt->set_thread_state(_thread_in_native);
543    }
544  }
545  notify_vm_shutdown();
546}
547
548void vm_shutdown()
549{
550  vm_perform_shutdown_actions();
551  os::wait_for_keypress_at_exit();
552  os::shutdown();
553}
554
555void vm_abort(bool dump_core) {
556  vm_perform_shutdown_actions();
557  os::wait_for_keypress_at_exit();
558  os::abort(dump_core);
559  ShouldNotReachHere();
560}
561
562void vm_notify_during_shutdown(const char* error, const char* message) {
563  if (error != NULL) {
564    tty->print_cr("Error occurred during initialization of VM");
565    tty->print("%s", error);
566    if (message != NULL) {
567      tty->print_cr(": %s", message);
568    }
569    else {
570      tty->cr();
571    }
572  }
573  if (ShowMessageBoxOnError && WizardMode) {
574    fatal("Error occurred during initialization of VM");
575  }
576}
577
578void vm_exit_during_initialization(Handle exception) {
579  tty->print_cr("Error occurred during initialization of VM");
580  // If there are exceptions on this thread it must be cleared
581  // first and here. Any future calls to EXCEPTION_MARK requires
582  // that no pending exceptions exist.
583  Thread *THREAD = Thread::current();
584  if (HAS_PENDING_EXCEPTION) {
585    CLEAR_PENDING_EXCEPTION;
586  }
587  java_lang_Throwable::print(exception, tty);
588  tty->cr();
589  java_lang_Throwable::print_stack_trace(exception(), tty);
590  tty->cr();
591  vm_notify_during_shutdown(NULL, NULL);
592
593  // Failure during initialization, we don't want to dump core
594  vm_abort(false);
595}
596
597void vm_exit_during_initialization(Symbol* ex, const char* message) {
598  ResourceMark rm;
599  vm_notify_during_shutdown(ex->as_C_string(), message);
600
601  // Failure during initialization, we don't want to dump core
602  vm_abort(false);
603}
604
605void vm_exit_during_initialization(const char* error, const char* message) {
606  vm_notify_during_shutdown(error, message);
607
608  // Failure during initialization, we don't want to dump core
609  vm_abort(false);
610}
611
612void vm_shutdown_during_initialization(const char* error, const char* message) {
613  vm_notify_during_shutdown(error, message);
614  vm_shutdown();
615}
616
617JDK_Version JDK_Version::_current;
618const char* JDK_Version::_runtime_name;
619const char* JDK_Version::_runtime_version;
620
621void JDK_Version::initialize() {
622  jdk_version_info info;
623  assert(!_current.is_valid(), "Don't initialize twice");
624
625  void *lib_handle = os::native_java_library();
626  jdk_version_info_fn_t func = CAST_TO_FN_PTR(jdk_version_info_fn_t,
627     os::dll_lookup(lib_handle, "JDK_GetVersionInfo0"));
628
629  if (func == NULL) {
630    // JDK older than 1.6
631    _current._partially_initialized = true;
632  } else {
633    (*func)(&info, sizeof(info));
634
635    int major = JDK_VERSION_MAJOR(info.jdk_version);
636    int minor = JDK_VERSION_MINOR(info.jdk_version);
637    int micro = JDK_VERSION_MICRO(info.jdk_version);
638    int build = JDK_VERSION_BUILD(info.jdk_version);
639    if (major == 1 && minor > 4) {
640      // We represent "1.5.0" as "5.0", but 1.4.2 as itself.
641      major = minor;
642      minor = micro;
643      micro = 0;
644    }
645    // Incompatible with pre-4243978 JDK.
646    if (info.pending_list_uses_discovered_field == 0) {
647      vm_exit_during_initialization(
648        "Incompatible JDK is not using Reference.discovered field for pending list");
649    }
650    _current = JDK_Version(major, minor, micro, info.update_version,
651                           info.special_update_version, build,
652                           info.thread_park_blocker == 1,
653                           info.post_vm_init_hook_enabled == 1);
654  }
655}
656
657void JDK_Version::fully_initialize(
658    uint8_t major, uint8_t minor, uint8_t micro, uint8_t update) {
659  // This is only called when current is less than 1.6 and we've gotten
660  // far enough in the initialization to determine the exact version.
661  assert(major < 6, "not needed for JDK version >= 6");
662  assert(is_partially_initialized(), "must not initialize");
663  if (major < 5) {
664    // JDK verison sequence: 1.2.x, 1.3.x, 1.4.x, 5.0.x, 6.0.x, etc.
665    micro = minor;
666    minor = major;
667    major = 1;
668  }
669  _current = JDK_Version(major, minor, micro, update);
670}
671
672void JDK_Version_init() {
673  JDK_Version::initialize();
674}
675
676static int64_t encode_jdk_version(const JDK_Version& v) {
677  return
678    ((int64_t)v.major_version()          << (BitsPerByte * 5)) |
679    ((int64_t)v.minor_version()          << (BitsPerByte * 4)) |
680    ((int64_t)v.micro_version()          << (BitsPerByte * 3)) |
681    ((int64_t)v.update_version()         << (BitsPerByte * 2)) |
682    ((int64_t)v.special_update_version() << (BitsPerByte * 1)) |
683    ((int64_t)v.build_number()           << (BitsPerByte * 0));
684}
685
686int JDK_Version::compare(const JDK_Version& other) const {
687  assert(is_valid() && other.is_valid(), "Invalid version (uninitialized?)");
688  if (!is_partially_initialized() && other.is_partially_initialized()) {
689    return -(other.compare(*this)); // flip the comparators
690  }
691  assert(!other.is_partially_initialized(), "Not initialized yet");
692  if (is_partially_initialized()) {
693    assert(other.major_version() >= 6,
694           "Invalid JDK version comparison during initialization");
695    return -1;
696  } else {
697    uint64_t e = encode_jdk_version(*this);
698    uint64_t o = encode_jdk_version(other);
699    return (e > o) ? 1 : ((e == o) ? 0 : -1);
700  }
701}
702
703void JDK_Version::to_string(char* buffer, size_t buflen) const {
704  assert(buffer && buflen > 0, "call with useful buffer");
705  size_t index = 0;
706
707  if (!is_valid()) {
708    jio_snprintf(buffer, buflen, "%s", "(uninitialized)");
709  } else if (is_partially_initialized()) {
710    jio_snprintf(buffer, buflen, "%s", "(uninitialized) pre-1.6.0");
711  } else {
712    int rc = jio_snprintf(
713        &buffer[index], buflen - index, "%d.%d", _major, _minor);
714    if (rc == -1) return;
715    index += rc;
716    if (_micro > 0) {
717      rc = jio_snprintf(&buffer[index], buflen - index, ".%d", _micro);
718    }
719    if (_update > 0) {
720      rc = jio_snprintf(&buffer[index], buflen - index, "_%02d", _update);
721      if (rc == -1) return;
722      index += rc;
723    }
724    if (_special > 0) {
725      rc = jio_snprintf(&buffer[index], buflen - index, "%c", _special);
726      if (rc == -1) return;
727      index += rc;
728    }
729    if (_build > 0) {
730      rc = jio_snprintf(&buffer[index], buflen - index, "-b%02d", _build);
731      if (rc == -1) return;
732      index += rc;
733    }
734  }
735}
736