1 /*
   2  * Copyright (c) 1999, 2026, 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 "cds/cdsConfig.hpp"
  26 #include "classfile/javaClasses.inline.hpp"
  27 #include "classfile/symbolTable.hpp"
  28 #include "classfile/vmClasses.hpp"
  29 #include "classfile/vmSymbols.hpp"
  30 #include "code/codeCache.hpp"
  31 #include "code/codeHeapState.hpp"
  32 #include "code/dependencyContext.hpp"
  33 #include "compiler/compilationLog.hpp"
  34 #include "compiler/compilationMemoryStatistic.hpp"
  35 #include "compiler/compilationPolicy.hpp"
  36 #include "compiler/compileBroker.hpp"
  37 #include "compiler/compileLog.hpp"
  38 #include "compiler/compilerEvent.hpp"
  39 #include "compiler/compilerOracle.hpp"
  40 #include "compiler/directivesParser.hpp"
  41 #include "gc/shared/memAllocator.hpp"
  42 #include "interpreter/linkResolver.hpp"
  43 #include "jfr/jfrEvents.hpp"
  44 #include "jvm.h"
  45 #include "logging/log.hpp"
  46 #include "logging/logStream.hpp"
  47 #include "memory/allocation.inline.hpp"
  48 #include "memory/resourceArea.hpp"
  49 #include "memory/universe.hpp"
  50 #include "oops/method.inline.hpp"
  51 #include "oops/methodData.hpp"
  52 #include "oops/oop.inline.hpp"
  53 #include "prims/jvmtiExport.hpp"
  54 #include "prims/nativeLookup.hpp"
  55 #include "prims/whitebox.hpp"
  56 #include "runtime/atomicAccess.hpp"
  57 #include "runtime/escapeBarrier.hpp"
  58 #include "runtime/globals_extension.hpp"
  59 #include "runtime/handles.inline.hpp"
  60 #include "runtime/init.hpp"
  61 #include "runtime/interfaceSupport.inline.hpp"
  62 #include "runtime/java.hpp"
  63 #include "runtime/javaCalls.hpp"
  64 #include "runtime/jniHandles.inline.hpp"
  65 #include "runtime/os.hpp"
  66 #include "runtime/perfData.hpp"
  67 #include "runtime/safepointVerifiers.hpp"
  68 #include "runtime/sharedRuntime.hpp"
  69 #include "runtime/threads.hpp"
  70 #include "runtime/threadSMR.hpp"
  71 #include "runtime/timerTrace.hpp"
  72 #include "runtime/vframe.inline.hpp"
  73 #include "utilities/debug.hpp"
  74 #include "utilities/dtrace.hpp"
  75 #include "utilities/events.hpp"
  76 #include "utilities/formatBuffer.hpp"
  77 #include "utilities/macros.hpp"
  78 #ifdef COMPILER1
  79 #include "c1/c1_Compiler.hpp"
  80 #endif
  81 #ifdef COMPILER2
  82 #include "opto/c2compiler.hpp"
  83 #endif
  84 #if INCLUDE_JVMCI
  85 #include "jvmci/jvmciEnv.hpp"
  86 #include "jvmci/jvmciRuntime.hpp"
  87 #endif
  88 
  89 #ifdef DTRACE_ENABLED
  90 
  91 // Only bother with this argument setup if dtrace is available
  92 
  93 #define DTRACE_METHOD_COMPILE_BEGIN_PROBE(method, comp_name)             \
  94   {                                                                      \
  95     Symbol* klass_name = (method)->klass_name();                         \
  96     Symbol* name = (method)->name();                                     \
  97     Symbol* signature = (method)->signature();                           \
  98     HOTSPOT_METHOD_COMPILE_BEGIN(                                        \
  99       (char *) comp_name, strlen(comp_name),                             \
 100       (char *) klass_name->bytes(), klass_name->utf8_length(),           \
 101       (char *) name->bytes(), name->utf8_length(),                       \
 102       (char *) signature->bytes(), signature->utf8_length());            \
 103   }
 104 
 105 #define DTRACE_METHOD_COMPILE_END_PROBE(method, comp_name, success)      \
 106   {                                                                      \
 107     Symbol* klass_name = (method)->klass_name();                         \
 108     Symbol* name = (method)->name();                                     \
 109     Symbol* signature = (method)->signature();                           \
 110     HOTSPOT_METHOD_COMPILE_END(                                          \
 111       (char *) comp_name, strlen(comp_name),                             \
 112       (char *) klass_name->bytes(), klass_name->utf8_length(),           \
 113       (char *) name->bytes(), name->utf8_length(),                       \
 114       (char *) signature->bytes(), signature->utf8_length(), (success)); \
 115   }
 116 
 117 #else //  ndef DTRACE_ENABLED
 118 
 119 #define DTRACE_METHOD_COMPILE_BEGIN_PROBE(method, comp_name)
 120 #define DTRACE_METHOD_COMPILE_END_PROBE(method, comp_name, success)
 121 
 122 #endif // ndef DTRACE_ENABLED
 123 
 124 bool CompileBroker::_initialized = false;
 125 volatile bool CompileBroker::_should_block = false;
 126 volatile int  CompileBroker::_print_compilation_warning = 0;
 127 volatile jint CompileBroker::_should_compile_new_jobs = run_compilation;
 128 
 129 // The installed compiler(s)
 130 AbstractCompiler* CompileBroker::_compilers[2];
 131 
 132 // The maximum numbers of compiler threads to be determined during startup.
 133 int CompileBroker::_c1_count = 0;
 134 int CompileBroker::_c2_count = 0;
 135 
 136 // An array of compiler names as Java String objects
 137 jobject* CompileBroker::_compiler1_objects = nullptr;
 138 jobject* CompileBroker::_compiler2_objects = nullptr;
 139 
 140 CompileLog** CompileBroker::_compiler1_logs = nullptr;
 141 CompileLog** CompileBroker::_compiler2_logs = nullptr;
 142 
 143 // These counters are used to assign an unique ID to each compilation.
 144 volatile jint CompileBroker::_compilation_id     = 0;
 145 volatile jint CompileBroker::_osr_compilation_id = 0;
 146 volatile jint CompileBroker::_native_compilation_id = 0;
 147 
 148 // Performance counters
 149 PerfCounter* CompileBroker::_perf_total_compilation = nullptr;
 150 PerfCounter* CompileBroker::_perf_osr_compilation = nullptr;
 151 PerfCounter* CompileBroker::_perf_standard_compilation = nullptr;
 152 
 153 PerfCounter* CompileBroker::_perf_total_bailout_count = nullptr;
 154 PerfCounter* CompileBroker::_perf_total_invalidated_count = nullptr;
 155 PerfCounter* CompileBroker::_perf_total_compile_count = nullptr;
 156 PerfCounter* CompileBroker::_perf_total_osr_compile_count = nullptr;
 157 PerfCounter* CompileBroker::_perf_total_standard_compile_count = nullptr;
 158 
 159 PerfCounter* CompileBroker::_perf_sum_osr_bytes_compiled = nullptr;
 160 PerfCounter* CompileBroker::_perf_sum_standard_bytes_compiled = nullptr;
 161 PerfCounter* CompileBroker::_perf_sum_nmethod_size = nullptr;
 162 PerfCounter* CompileBroker::_perf_sum_nmethod_code_size = nullptr;
 163 
 164 PerfStringVariable* CompileBroker::_perf_last_method = nullptr;
 165 PerfStringVariable* CompileBroker::_perf_last_failed_method = nullptr;
 166 PerfStringVariable* CompileBroker::_perf_last_invalidated_method = nullptr;
 167 PerfVariable*       CompileBroker::_perf_last_compile_type = nullptr;
 168 PerfVariable*       CompileBroker::_perf_last_compile_size = nullptr;
 169 PerfVariable*       CompileBroker::_perf_last_failed_type = nullptr;
 170 PerfVariable*       CompileBroker::_perf_last_invalidated_type = nullptr;
 171 
 172 // Timers and counters for generating statistics
 173 elapsedTimer CompileBroker::_t_total_compilation;
 174 elapsedTimer CompileBroker::_t_osr_compilation;
 175 elapsedTimer CompileBroker::_t_standard_compilation;
 176 elapsedTimer CompileBroker::_t_invalidated_compilation;
 177 elapsedTimer CompileBroker::_t_bailedout_compilation;
 178 
 179 uint CompileBroker::_total_bailout_count            = 0;
 180 uint CompileBroker::_total_invalidated_count        = 0;
 181 uint CompileBroker::_total_compile_count            = 0;
 182 uint CompileBroker::_total_osr_compile_count        = 0;
 183 uint CompileBroker::_total_standard_compile_count   = 0;
 184 uint CompileBroker::_total_compiler_stopped_count   = 0;
 185 uint CompileBroker::_total_compiler_restarted_count = 0;
 186 
 187 uint CompileBroker::_sum_osr_bytes_compiled         = 0;
 188 uint CompileBroker::_sum_standard_bytes_compiled    = 0;
 189 uint CompileBroker::_sum_nmethod_size               = 0;
 190 uint CompileBroker::_sum_nmethod_code_size          = 0;
 191 uint CompileBroker::_largest_nmethod_code_size      = 0;
 192 
 193 jlong CompileBroker::_peak_compilation_time        = 0;
 194 
 195 CompilerStatistics CompileBroker::_stats_per_level[CompLevel_full_optimization];
 196 
 197 CompileQueue* CompileBroker::_c2_compile_queue     = nullptr;
 198 CompileQueue* CompileBroker::_c1_compile_queue     = nullptr;
 199 
 200 bool compileBroker_init() {
 201   if (LogEvents) {
 202     CompilationLog::init();
 203   }
 204 
 205   // init directives stack, adding default directive
 206   DirectivesStack::init();
 207 
 208   if (DirectivesParser::has_file()) {
 209     return DirectivesParser::parse_from_flag();
 210   } else if (CompilerDirectivesPrint) {
 211     // Print default directive even when no other was added
 212     DirectivesStack::print(tty);
 213   }
 214 
 215   return true;
 216 }
 217 
 218 CompileTaskWrapper::CompileTaskWrapper(CompileTask* task) {
 219   CompilerThread* thread = CompilerThread::current();
 220   thread->set_task(task);
 221   CompileLog*     log  = thread->log();
 222   thread->timeout()->arm();
 223   if (log != nullptr && !task->is_unloaded())  task->log_task_start(log);
 224 }
 225 
 226 CompileTaskWrapper::~CompileTaskWrapper() {
 227   CompilerThread* thread = CompilerThread::current();
 228 
 229   // First, disarm the timeout. This still relies on the underlying task.
 230   thread->timeout()->disarm();
 231 
 232   CompileTask* task = thread->task();
 233   CompileLog*  log  = thread->log();
 234   if (log != nullptr && !task->is_unloaded())  task->log_task_done(log);
 235   thread->set_task(nullptr);
 236   thread->set_env(nullptr);
 237   if (task->is_blocking()) {
 238     bool free_task = false;
 239     {
 240       MutexLocker notifier(thread, CompileTaskWait_lock);
 241       task->mark_complete();
 242 #if INCLUDE_JVMCI
 243       if (CompileBroker::compiler(task->comp_level())->is_jvmci()) {
 244         if (!task->has_waiter()) {
 245           // The waiting thread timed out and thus did not delete the task.
 246           free_task = true;
 247         }
 248         task->set_blocking_jvmci_compile_state(nullptr);
 249       }
 250 #endif
 251       if (!free_task) {
 252         // Notify the waiting thread that the compilation has completed
 253         // so that it can free the task.
 254         CompileTaskWait_lock->notify_all();
 255       }
 256     }
 257     if (free_task) {
 258       // The task can only be deleted once the task lock is released.
 259       delete task;
 260     }
 261   } else {
 262     task->mark_complete();
 263 
 264     // By convention, the compiling thread is responsible for deleting
 265     // a non-blocking CompileTask.
 266     delete task;
 267   }
 268 }
 269 
 270 /**
 271  * Check if a CompilerThread can be removed and update count if requested.
 272  */
 273 bool CompileBroker::can_remove(CompilerThread *ct, bool do_it) {
 274   assert(UseDynamicNumberOfCompilerThreads, "or shouldn't be here");
 275   if (!ReduceNumberOfCompilerThreads) return false;
 276 
 277   AbstractCompiler *compiler = ct->compiler();
 278   int compiler_count = compiler->num_compiler_threads();
 279   bool c1 = compiler->is_c1();
 280 
 281   // Keep at least 1 compiler thread of each type.
 282   if (compiler_count < 2) return false;
 283 
 284   // Keep thread alive for at least some time.
 285   if (ct->idle_time_millis() < (c1 ? 500 : 100)) return false;
 286 
 287 #if INCLUDE_JVMCI
 288   if (compiler->is_jvmci() && !UseJVMCINativeLibrary) {
 289     // Handles for JVMCI thread objects may get released concurrently.
 290     if (do_it) {
 291       assert(CompileThread_lock->owner() == ct, "must be holding lock");
 292     } else {
 293       // Skip check if it's the last thread and let caller check again.
 294       return true;
 295     }
 296   }
 297 #endif
 298 
 299   // We only allow the last compiler thread of each type to get removed.
 300   jobject last_compiler = c1 ? compiler1_object(compiler_count - 1)
 301                              : compiler2_object(compiler_count - 1);
 302   if (ct->threadObj() == JNIHandles::resolve_non_null(last_compiler)) {
 303     if (do_it) {
 304       assert_locked_or_safepoint(CompileThread_lock); // Update must be consistent.
 305       compiler->set_num_compiler_threads(compiler_count - 1);
 306 #if INCLUDE_JVMCI
 307       if (compiler->is_jvmci() && !UseJVMCINativeLibrary) {
 308         // Old j.l.Thread object can die when no longer referenced elsewhere.
 309         JNIHandles::destroy_global(compiler2_object(compiler_count - 1));
 310         _compiler2_objects[compiler_count - 1] = nullptr;
 311       }
 312 #endif
 313     }
 314     return true;
 315   }
 316   return false;
 317 }
 318 
 319 /**
 320  * Add a CompileTask to a CompileQueue.
 321  */
 322 void CompileQueue::add(CompileTask* task) {
 323   assert(MethodCompileQueue_lock->owned_by_self(), "must own lock");
 324 
 325   task->set_next(nullptr);
 326   task->set_prev(nullptr);
 327 
 328   if (_last == nullptr) {
 329     // The compile queue is empty.
 330     assert(_first == nullptr, "queue is empty");
 331     _first = task;
 332     _last = task;
 333   } else {
 334     // Append the task to the queue.
 335     assert(_last->next() == nullptr, "not last");
 336     _last->set_next(task);
 337     task->set_prev(_last);
 338     _last = task;
 339   }
 340   ++_size;
 341   ++_total_added;
 342   if (_size > _peak_size) {
 343     _peak_size = _size;
 344   }
 345 
 346   // Mark the method as being in the compile queue.
 347   task->method()->set_queued_for_compilation();
 348 
 349   if (CIPrintCompileQueue) {
 350     print_tty();
 351   }
 352 
 353   if (LogCompilation && xtty != nullptr) {
 354     task->log_task_queued();
 355   }
 356 
 357   if (TrainingData::need_data() && !CDSConfig::is_dumping_final_static_archive()) {
 358     CompileTrainingData* ctd = CompileTrainingData::make(task);
 359     if (ctd != nullptr) {
 360       task->set_training_data(ctd);
 361     }
 362   }
 363 
 364   // Notify CompilerThreads that a task is available.
 365   MethodCompileQueue_lock->notify_all();
 366 }
 367 
 368 /**
 369  * Empties compilation queue by deleting all compilation tasks.
 370  * Furthermore, the method wakes up all threads that are waiting
 371  * on a compilation task to finish. This can happen if background
 372  * compilation is disabled.
 373  */
 374 void CompileQueue::delete_all() {
 375   MutexLocker mu(MethodCompileQueue_lock);
 376   CompileTask* current = _first;
 377 
 378   // Iterate over all tasks in the compile queue
 379   while (current != nullptr) {
 380     CompileTask* next = current->next();
 381     if (!current->is_blocking()) {
 382       // Non-blocking task. No one is waiting for it, delete it now.
 383       delete current;
 384     } else {
 385       // Blocking task. By convention, it is the waiters responsibility
 386       // to delete the task. We cannot delete it here, because we do not
 387       // coordinate with waiters. We will notify the waiters later.
 388     }
 389     current = next;
 390   }
 391   _first = nullptr;
 392   _last = nullptr;
 393 
 394   // Wake up all blocking task waiters to deal with remaining blocking
 395   // tasks. This is not a performance sensitive path, so we do this
 396   // unconditionally to simplify coding/testing.
 397   {
 398     MonitorLocker ml(Thread::current(), CompileTaskWait_lock);
 399     ml.notify_all();
 400   }
 401 
 402   // Wake up all threads that block on the queue.
 403   MethodCompileQueue_lock->notify_all();
 404 }
 405 
 406 /**
 407  * Get the next CompileTask from a CompileQueue
 408  */
 409 CompileTask* CompileQueue::get(CompilerThread* thread) {
 410   // save methods from RedefineClasses across safepoint
 411   // across MethodCompileQueue_lock below.
 412   methodHandle save_method;
 413 
 414   MonitorLocker locker(MethodCompileQueue_lock);
 415   // If _first is null we have no more compile jobs. There are two reasons for
 416   // having no compile jobs: First, we compiled everything we wanted. Second,
 417   // we ran out of code cache so compilation has been disabled. In the latter
 418   // case we perform code cache sweeps to free memory such that we can re-enable
 419   // compilation.
 420   while (_first == nullptr) {
 421     // Exit loop if compilation is disabled forever
 422     if (CompileBroker::is_compilation_disabled_forever()) {
 423       return nullptr;
 424     }
 425 
 426     AbstractCompiler* compiler = thread->compiler();
 427     guarantee(compiler != nullptr, "Compiler object must exist");
 428     compiler->on_empty_queue(this, thread);
 429     if (_first != nullptr) {
 430       // The call to on_empty_queue may have temporarily unlocked the MCQ lock
 431       // so check again whether any tasks were added to the queue.
 432       break;
 433     }
 434 
 435     // If there are no compilation tasks and we can compile new jobs
 436     // (i.e., there is enough free space in the code cache) there is
 437     // no need to invoke the GC.
 438     // We need a timed wait here, since compiler threads can exit if compilation
 439     // is disabled forever. We use 5 seconds wait time; the exiting of compiler threads
 440     // is not critical and we do not want idle compiler threads to wake up too often.
 441     locker.wait(5*1000);
 442 
 443     if (UseDynamicNumberOfCompilerThreads && _first == nullptr) {
 444       // Still nothing to compile. Give caller a chance to stop this thread.
 445       if (CompileBroker::can_remove(CompilerThread::current(), false)) return nullptr;
 446     }
 447   }
 448 
 449   if (CompileBroker::is_compilation_disabled_forever()) {
 450     return nullptr;
 451   }
 452 
 453   CompileTask* task;
 454   {
 455     NoSafepointVerifier nsv;
 456     task = CompilationPolicy::select_task(this, thread);
 457     if (task != nullptr) {
 458       task = task->select_for_compilation();
 459     }
 460   }
 461 
 462   if (task != nullptr) {
 463     // Save method pointers across unlock safepoint.  The task is removed from
 464     // the compilation queue, which is walked during RedefineClasses.
 465     Thread* thread = Thread::current();
 466     save_method = methodHandle(thread, task->method());
 467 
 468     remove(task);
 469   }
 470   purge_stale_tasks(); // may temporarily release MCQ lock
 471   return task;
 472 }
 473 
 474 // Clean & deallocate stale compile tasks.
 475 // Temporarily releases MethodCompileQueue lock.
 476 void CompileQueue::purge_stale_tasks() {
 477   assert(MethodCompileQueue_lock->owned_by_self(), "must own lock");
 478   if (_first_stale != nullptr) {
 479     // Stale tasks are purged when MCQ lock is released,
 480     // but _first_stale updates are protected by MCQ lock.
 481     // Once task processing starts and MCQ lock is released,
 482     // other compiler threads can reuse _first_stale.
 483     CompileTask* head = _first_stale;
 484     _first_stale = nullptr;
 485     {
 486       MutexUnlocker ul(MethodCompileQueue_lock);
 487       for (CompileTask* task = head; task != nullptr; ) {
 488         CompileTask* next_task = task->next();
 489         task->set_next(nullptr);
 490         CompileTaskWrapper ctw(task); // Frees the task
 491         task->set_failure_reason("stale task");
 492         task = next_task;
 493       }
 494     }
 495   }
 496 }
 497 
 498 void CompileQueue::remove(CompileTask* task) {
 499   assert(MethodCompileQueue_lock->owned_by_self(), "must own lock");
 500   if (task->prev() != nullptr) {
 501     task->prev()->set_next(task->next());
 502   } else {
 503     // max is the first element
 504     assert(task == _first, "Sanity");
 505     _first = task->next();
 506   }
 507 
 508   if (task->next() != nullptr) {
 509     task->next()->set_prev(task->prev());
 510   } else {
 511     // max is the last element
 512     assert(task == _last, "Sanity");
 513     _last = task->prev();
 514   }
 515   task->set_next(nullptr);
 516   task->set_prev(nullptr);
 517   --_size;
 518   ++_total_removed;
 519 }
 520 
 521 void CompileQueue::remove_and_mark_stale(CompileTask* task) {
 522   assert(MethodCompileQueue_lock->owned_by_self(), "must own lock");
 523   remove(task);
 524 
 525   // Enqueue the task for reclamation (should be done outside MCQ lock)
 526   task->set_next(_first_stale);
 527   task->set_prev(nullptr);
 528   _first_stale = task;
 529 }
 530 
 531 // methods in the compile queue need to be marked as used on the stack
 532 // so that they don't get reclaimed by Redefine Classes
 533 void CompileQueue::mark_on_stack() {
 534   CompileTask* task = _first;
 535   while (task != nullptr) {
 536     task->mark_on_stack();
 537     task = task->next();
 538   }
 539 }
 540 
 541 
 542 CompileQueue* CompileBroker::compile_queue(int comp_level) {
 543   if (is_c2_compile(comp_level)) return _c2_compile_queue;
 544   if (is_c1_compile(comp_level)) return _c1_compile_queue;
 545   return nullptr;
 546 }
 547 
 548 CompileQueue* CompileBroker::c1_compile_queue() {
 549   return _c1_compile_queue;
 550 }
 551 
 552 CompileQueue* CompileBroker::c2_compile_queue() {
 553   return _c2_compile_queue;
 554 }
 555 
 556 void CompileBroker::print_compile_queues(outputStream* st) {
 557   st->print_cr("Current compiles: ");
 558 
 559   char buf[2000];
 560   int buflen = sizeof(buf);
 561   Threads::print_threads_compiling(st, buf, buflen, /* short_form = */ true);
 562 
 563   st->cr();
 564   if (_c1_compile_queue != nullptr) {
 565     _c1_compile_queue->print(st);
 566   }
 567   if (_c2_compile_queue != nullptr) {
 568     _c2_compile_queue->print(st);
 569   }
 570 }
 571 
 572 void CompileQueue::print(outputStream* st) {
 573   assert_locked_or_safepoint(MethodCompileQueue_lock);
 574   st->print_cr("%s:", name());
 575   CompileTask* task = _first;
 576   if (task == nullptr) {
 577     st->print_cr("Empty");
 578   } else {
 579     while (task != nullptr) {
 580       task->print(st, nullptr, true, true);
 581       task = task->next();
 582     }
 583   }
 584   st->cr();
 585 }
 586 
 587 void CompileQueue::print_tty() {
 588   stringStream ss;
 589   // Dump the compile queue into a buffer before locking the tty
 590   print(&ss);
 591   {
 592     ttyLocker ttyl;
 593     tty->print("%s", ss.freeze());
 594   }
 595 }
 596 
 597 CompilerCounters::CompilerCounters() {
 598   _current_method[0] = '\0';
 599   _compile_type = CompileBroker::no_compile;
 600 }
 601 
 602 #if INCLUDE_JFR && COMPILER2_OR_JVMCI
 603 // It appends new compiler phase names to growable array phase_names(a new CompilerPhaseType mapping
 604 // in compiler/compilerEvent.cpp) and registers it with its serializer.
 605 //
 606 // c2 uses explicit CompilerPhaseType idToPhase mapping in opto/phasetype.hpp,
 607 // so if c2 is used, it should be always registered first.
 608 // This function is called during vm initialization.
 609 static void register_jfr_phasetype_serializer(CompilerType compiler_type) {
 610   ResourceMark rm;
 611   static bool first_registration = true;
 612   if (compiler_type == compiler_jvmci) {
 613     CompilerEvent::PhaseEvent::get_phase_id("NOT_A_PHASE_NAME", false, false, false);
 614     first_registration = false;
 615 #ifdef COMPILER2
 616   } else if (compiler_type == compiler_c2) {
 617     assert(first_registration, "invariant"); // c2 must be registered first.
 618     for (int i = 0; i < PHASE_NUM_TYPES; i++) {
 619       const char* phase_name = CompilerPhaseTypeHelper::to_description((CompilerPhaseType) i);
 620       CompilerEvent::PhaseEvent::get_phase_id(phase_name, false, false, false);
 621     }
 622     first_registration = false;
 623 #endif // COMPILER2
 624   }
 625 }
 626 #endif // INCLUDE_JFR && COMPILER2_OR_JVMCI
 627 
 628 // ------------------------------------------------------------------
 629 // CompileBroker::compilation_init
 630 //
 631 // Initialize the Compilation object
 632 void CompileBroker::compilation_init(JavaThread* THREAD) {
 633   // No need to initialize compilation system if we do not use it.
 634   if (!UseCompiler) {
 635     return;
 636   }
 637   // Set the interface to the current compiler(s).
 638   _c1_count = CompilationPolicy::c1_count();
 639   _c2_count = CompilationPolicy::c2_count();
 640 
 641 #if INCLUDE_JVMCI
 642   if (EnableJVMCI) {
 643     // This is creating a JVMCICompiler singleton.
 644     JVMCICompiler* jvmci = new JVMCICompiler();
 645 
 646     if (UseJVMCICompiler) {
 647       _compilers[1] = jvmci;
 648       if (FLAG_IS_DEFAULT(JVMCIThreads)) {
 649         if (BootstrapJVMCI) {
 650           // JVMCI will bootstrap so give it more threads
 651           _c2_count = MIN2(32, os::active_processor_count());
 652         }
 653       } else {
 654         _c2_count = JVMCIThreads;
 655       }
 656       if (FLAG_IS_DEFAULT(JVMCIHostThreads)) {
 657       } else {
 658 #ifdef COMPILER1
 659         _c1_count = JVMCIHostThreads;
 660 #endif // COMPILER1
 661       }
 662     }
 663   }
 664 #endif // INCLUDE_JVMCI
 665 
 666 #ifdef COMPILER1
 667   if (_c1_count > 0) {
 668     _compilers[0] = new Compiler();
 669   }
 670 #endif // COMPILER1
 671 
 672 #ifdef COMPILER2
 673   if (true JVMCI_ONLY( && !UseJVMCICompiler)) {
 674     if (_c2_count > 0) {
 675       _compilers[1] = new C2Compiler();
 676       // Register c2 first as c2 CompilerPhaseType idToPhase mapping is explicit.
 677       // idToPhase mapping for c2 is in opto/phasetype.hpp
 678       JFR_ONLY(register_jfr_phasetype_serializer(compiler_c2);)
 679     }
 680   }
 681 #endif // COMPILER2
 682 
 683 #if INCLUDE_JVMCI
 684    // Register after c2 registration.
 685    // JVMCI CompilerPhaseType idToPhase mapping is dynamic.
 686    if (EnableJVMCI) {
 687      JFR_ONLY(register_jfr_phasetype_serializer(compiler_jvmci);)
 688    }
 689 #endif // INCLUDE_JVMCI
 690 
 691   if (CompilerOracle::should_collect_memstat()) {
 692     CompilationMemoryStatistic::initialize();
 693   }
 694 
 695   // Start the compiler thread(s)
 696   init_compiler_threads();
 697   // totalTime performance counter is always created as it is required
 698   // by the implementation of java.lang.management.CompilationMXBean.
 699   {
 700     // Ensure OOM leads to vm_exit_during_initialization.
 701     EXCEPTION_MARK;
 702     _perf_total_compilation =
 703                  PerfDataManager::create_counter(JAVA_CI, "totalTime",
 704                                                  PerfData::U_Ticks, CHECK);
 705   }
 706 
 707   if (UsePerfData) {
 708 
 709     EXCEPTION_MARK;
 710 
 711     // create the jvmstat performance counters
 712     _perf_osr_compilation =
 713                  PerfDataManager::create_counter(SUN_CI, "osrTime",
 714                                                  PerfData::U_Ticks, CHECK);
 715 
 716     _perf_standard_compilation =
 717                  PerfDataManager::create_counter(SUN_CI, "standardTime",
 718                                                  PerfData::U_Ticks, CHECK);
 719 
 720     _perf_total_bailout_count =
 721                  PerfDataManager::create_counter(SUN_CI, "totalBailouts",
 722                                                  PerfData::U_Events, CHECK);
 723 
 724     _perf_total_invalidated_count =
 725                  PerfDataManager::create_counter(SUN_CI, "totalInvalidates",
 726                                                  PerfData::U_Events, CHECK);
 727 
 728     _perf_total_compile_count =
 729                  PerfDataManager::create_counter(SUN_CI, "totalCompiles",
 730                                                  PerfData::U_Events, CHECK);
 731     _perf_total_osr_compile_count =
 732                  PerfDataManager::create_counter(SUN_CI, "osrCompiles",
 733                                                  PerfData::U_Events, CHECK);
 734 
 735     _perf_total_standard_compile_count =
 736                  PerfDataManager::create_counter(SUN_CI, "standardCompiles",
 737                                                  PerfData::U_Events, CHECK);
 738 
 739     _perf_sum_osr_bytes_compiled =
 740                  PerfDataManager::create_counter(SUN_CI, "osrBytes",
 741                                                  PerfData::U_Bytes, CHECK);
 742 
 743     _perf_sum_standard_bytes_compiled =
 744                  PerfDataManager::create_counter(SUN_CI, "standardBytes",
 745                                                  PerfData::U_Bytes, CHECK);
 746 
 747     _perf_sum_nmethod_size =
 748                  PerfDataManager::create_counter(SUN_CI, "nmethodSize",
 749                                                  PerfData::U_Bytes, CHECK);
 750 
 751     _perf_sum_nmethod_code_size =
 752                  PerfDataManager::create_counter(SUN_CI, "nmethodCodeSize",
 753                                                  PerfData::U_Bytes, CHECK);
 754 
 755     _perf_last_method =
 756                  PerfDataManager::create_string_variable(SUN_CI, "lastMethod",
 757                                        CompilerCounters::cmname_buffer_length,
 758                                        "", CHECK);
 759 
 760     _perf_last_failed_method =
 761             PerfDataManager::create_string_variable(SUN_CI, "lastFailedMethod",
 762                                        CompilerCounters::cmname_buffer_length,
 763                                        "", CHECK);
 764 
 765     _perf_last_invalidated_method =
 766         PerfDataManager::create_string_variable(SUN_CI, "lastInvalidatedMethod",
 767                                      CompilerCounters::cmname_buffer_length,
 768                                      "", CHECK);
 769 
 770     _perf_last_compile_type =
 771              PerfDataManager::create_variable(SUN_CI, "lastType",
 772                                               PerfData::U_None,
 773                                               (jlong)CompileBroker::no_compile,
 774                                               CHECK);
 775 
 776     _perf_last_compile_size =
 777              PerfDataManager::create_variable(SUN_CI, "lastSize",
 778                                               PerfData::U_Bytes,
 779                                               (jlong)CompileBroker::no_compile,
 780                                               CHECK);
 781 
 782 
 783     _perf_last_failed_type =
 784              PerfDataManager::create_variable(SUN_CI, "lastFailedType",
 785                                               PerfData::U_None,
 786                                               (jlong)CompileBroker::no_compile,
 787                                               CHECK);
 788 
 789     _perf_last_invalidated_type =
 790          PerfDataManager::create_variable(SUN_CI, "lastInvalidatedType",
 791                                           PerfData::U_None,
 792                                           (jlong)CompileBroker::no_compile,
 793                                           CHECK);
 794   }
 795 
 796   _initialized = true;
 797 }
 798 
 799 void TrainingReplayThread::training_replay_thread_entry(JavaThread* thread, TRAPS) {
 800   CompilationPolicy::replay_training_at_init_loop(thread);
 801 }
 802 
 803 #if defined(ASSERT) && COMPILER2_OR_JVMCI
 804 // Entry for DeoptimizeObjectsALotThread. The threads are started in
 805 // CompileBroker::init_compiler_threads() iff DeoptimizeObjectsALot is enabled
 806 void DeoptimizeObjectsALotThread::deopt_objs_alot_thread_entry(JavaThread* thread, TRAPS) {
 807     DeoptimizeObjectsALotThread* dt = ((DeoptimizeObjectsALotThread*) thread);
 808     bool enter_single_loop;
 809     {
 810       MonitorLocker ml(dt, EscapeBarrier_lock, Mutex::_no_safepoint_check_flag);
 811       static int single_thread_count = 0;
 812       enter_single_loop = single_thread_count++ < DeoptimizeObjectsALotThreadCountSingle;
 813     }
 814     if (enter_single_loop) {
 815       dt->deoptimize_objects_alot_loop_single();
 816     } else {
 817       dt->deoptimize_objects_alot_loop_all();
 818     }
 819   }
 820 
 821 // Execute EscapeBarriers in an endless loop to revert optimizations based on escape analysis. Each
 822 // barrier targets a single thread which is selected round robin.
 823 void DeoptimizeObjectsALotThread::deoptimize_objects_alot_loop_single() {
 824   HandleMark hm(this);
 825   while (true) {
 826     for (JavaThreadIteratorWithHandle jtiwh; JavaThread *deoptee_thread = jtiwh.next(); ) {
 827       { // Begin new scope for escape barrier
 828         HandleMarkCleaner hmc(this);
 829         ResourceMark rm(this);
 830         EscapeBarrier eb(true, this, deoptee_thread);
 831         eb.deoptimize_objects(100);
 832       }
 833       // Now sleep after the escape barriers destructor resumed deoptee_thread.
 834       sleep(DeoptimizeObjectsALotInterval);
 835     }
 836   }
 837 }
 838 
 839 // Execute EscapeBarriers in an endless loop to revert optimizations based on escape analysis. Each
 840 // barrier targets all java threads in the vm at once.
 841 void DeoptimizeObjectsALotThread::deoptimize_objects_alot_loop_all() {
 842   HandleMark hm(this);
 843   while (true) {
 844     { // Begin new scope for escape barrier
 845       HandleMarkCleaner hmc(this);
 846       ResourceMark rm(this);
 847       EscapeBarrier eb(true, this);
 848       eb.deoptimize_objects_all_threads();
 849     }
 850     // Now sleep after the escape barriers destructor resumed the java threads.
 851     sleep(DeoptimizeObjectsALotInterval);
 852   }
 853 }
 854 #endif // defined(ASSERT) && COMPILER2_OR_JVMCI
 855 
 856 
 857 JavaThread* CompileBroker::make_thread(ThreadType type, jobject thread_handle, CompileQueue* queue, AbstractCompiler* comp, JavaThread* THREAD) {
 858   Handle thread_oop(THREAD, JNIHandles::resolve_non_null(thread_handle));
 859 
 860   if (java_lang_Thread::thread(thread_oop()) != nullptr) {
 861     assert(type == compiler_t, "should only happen with reused compiler threads");
 862     // The compiler thread hasn't actually exited yet so don't try to reuse it
 863     return nullptr;
 864   }
 865 
 866   JavaThread* new_thread = nullptr;
 867   switch (type) {
 868     case compiler_t:
 869       assert(comp != nullptr, "Compiler instance missing.");
 870       if (!InjectCompilerCreationFailure || comp->num_compiler_threads() == 0) {
 871         CompilerCounters* counters = new CompilerCounters();
 872         new_thread = new CompilerThread(queue, counters);
 873       }
 874       break;
 875 #if defined(ASSERT) && COMPILER2_OR_JVMCI
 876     case deoptimizer_t:
 877       new_thread = new DeoptimizeObjectsALotThread();
 878       break;
 879 #endif // ASSERT
 880     case training_replay_t:
 881       new_thread = new TrainingReplayThread();
 882       break;
 883     default:
 884       ShouldNotReachHere();
 885   }
 886 
 887   // At this point the new CompilerThread data-races with this startup
 888   // thread (which is the main thread and NOT the VM thread).
 889   // This means Java bytecodes being executed at startup can
 890   // queue compile jobs which will run at whatever default priority the
 891   // newly created CompilerThread runs at.
 892 
 893 
 894   // At this point it may be possible that no osthread was created for the
 895   // JavaThread due to lack of resources. We will handle that failure below.
 896   // Also check new_thread so that static analysis is happy.
 897   if (new_thread != nullptr && new_thread->osthread() != nullptr) {
 898 
 899     if (type == compiler_t) {
 900       CompilerThread::cast(new_thread)->set_compiler(comp);
 901     }
 902 
 903     // Note that we cannot call os::set_priority because it expects Java
 904     // priorities and we are *explicitly* using OS priorities so that it's
 905     // possible to set the compiler thread priority higher than any Java
 906     // thread.
 907 
 908     int native_prio = CompilerThreadPriority;
 909     if (native_prio == -1) {
 910       if (UseCriticalCompilerThreadPriority) {
 911         native_prio = os::java_to_os_priority[CriticalPriority];
 912       } else {
 913         native_prio = os::java_to_os_priority[NearMaxPriority];
 914       }
 915     }
 916     os::set_native_priority(new_thread, native_prio);
 917 
 918     // Note that this only sets the JavaThread _priority field, which by
 919     // definition is limited to Java priorities and not OS priorities.
 920     JavaThread::start_internal_daemon(THREAD, new_thread, thread_oop, NearMaxPriority);
 921 
 922   } else { // osthread initialization failure
 923     if (UseDynamicNumberOfCompilerThreads && type == compiler_t
 924         && comp->num_compiler_threads() > 0) {
 925       // The new thread is not known to Thread-SMR yet so we can just delete.
 926       delete new_thread;
 927       return nullptr;
 928     } else {
 929       vm_exit_during_initialization("java.lang.OutOfMemoryError",
 930                                     os::native_thread_creation_failed_msg());
 931     }
 932   }
 933 
 934   os::naked_yield(); // make sure that the compiler thread is started early (especially helpful on SOLARIS)
 935 
 936   return new_thread;
 937 }
 938 
 939 static bool trace_compiler_threads() {
 940   LogTarget(Debug, jit, thread) lt;
 941   return TraceCompilerThreads || lt.is_enabled();
 942 }
 943 
 944 static jobject create_compiler_thread(AbstractCompiler* compiler, int i, TRAPS) {
 945   char name_buffer[256];
 946   os::snprintf_checked(name_buffer, sizeof(name_buffer), "%s CompilerThread%d", compiler->name(), i);
 947   Handle thread_oop = JavaThread::create_system_thread_object(name_buffer, CHECK_NULL);
 948   return JNIHandles::make_global(thread_oop);
 949 }
 950 
 951 static void print_compiler_threads(stringStream& msg) {
 952   if (TraceCompilerThreads) {
 953     tty->print_cr("%7d %s", (int)tty->time_stamp().milliseconds(), msg.as_string());
 954   }
 955   LogTarget(Debug, jit, thread) lt;
 956   if (lt.is_enabled()) {
 957     LogStream ls(lt);
 958     ls.print_cr("%s", msg.as_string());
 959   }
 960 }
 961 
 962 void CompileBroker::init_compiler_threads() {
 963   // Ensure any exceptions lead to vm_exit_during_initialization.
 964   EXCEPTION_MARK;
 965 #if !defined(ZERO)
 966   assert(_c2_count > 0 || _c1_count > 0, "No compilers?");
 967 #endif // !ZERO
 968   // Initialize the compilation queue
 969   if (_c2_count > 0) {
 970     const char* name = JVMCI_ONLY(UseJVMCICompiler ? "JVMCI compile queue" :) "C2 compile queue";
 971     _c2_compile_queue  = new CompileQueue(name);
 972     _compiler2_objects = NEW_C_HEAP_ARRAY(jobject, _c2_count, mtCompiler);
 973     _compiler2_logs = NEW_C_HEAP_ARRAY(CompileLog*, _c2_count, mtCompiler);
 974   }
 975   if (_c1_count > 0) {
 976     _c1_compile_queue  = new CompileQueue("C1 compile queue");
 977     _compiler1_objects = NEW_C_HEAP_ARRAY(jobject, _c1_count, mtCompiler);
 978     _compiler1_logs = NEW_C_HEAP_ARRAY(CompileLog*, _c1_count, mtCompiler);
 979   }
 980 
 981   for (int i = 0; i < _c2_count; i++) {
 982     // Create a name for our thread.
 983     jobject thread_handle = create_compiler_thread(_compilers[1], i, CHECK);
 984     _compiler2_objects[i] = thread_handle;
 985     _compiler2_logs[i] = nullptr;
 986 
 987     if (!UseDynamicNumberOfCompilerThreads || i == 0) {
 988       JavaThread *ct = make_thread(compiler_t, thread_handle, _c2_compile_queue, _compilers[1], THREAD);
 989       assert(ct != nullptr, "should have been handled for initial thread");
 990       _compilers[1]->set_num_compiler_threads(i + 1);
 991       if (trace_compiler_threads()) {
 992         ResourceMark rm;
 993         ThreadsListHandle tlh;  // name() depends on the TLH.
 994         assert(tlh.includes(ct), "ct=" INTPTR_FORMAT " exited unexpectedly.", p2i(ct));
 995         stringStream msg;
 996         msg.print("Added initial compiler thread %s", ct->name());
 997         print_compiler_threads(msg);
 998       }
 999     }
1000   }
1001 
1002   for (int i = 0; i < _c1_count; i++) {
1003     // Create a name for our thread.
1004     jobject thread_handle = create_compiler_thread(_compilers[0], i, CHECK);
1005     _compiler1_objects[i] = thread_handle;
1006     _compiler1_logs[i] = nullptr;
1007 
1008     if (!UseDynamicNumberOfCompilerThreads || i == 0) {
1009       JavaThread *ct = make_thread(compiler_t, thread_handle, _c1_compile_queue, _compilers[0], THREAD);
1010       assert(ct != nullptr, "should have been handled for initial thread");
1011       _compilers[0]->set_num_compiler_threads(i + 1);
1012       if (trace_compiler_threads()) {
1013         ResourceMark rm;
1014         ThreadsListHandle tlh;  // name() depends on the TLH.
1015         assert(tlh.includes(ct), "ct=" INTPTR_FORMAT " exited unexpectedly.", p2i(ct));
1016         stringStream msg;
1017         msg.print("Added initial compiler thread %s", ct->name());
1018         print_compiler_threads(msg);
1019       }
1020     }
1021   }
1022 
1023   if (UsePerfData) {
1024     PerfDataManager::create_constant(SUN_CI, "threads", PerfData::U_Bytes, _c1_count + _c2_count, CHECK);
1025   }
1026 
1027 #if defined(ASSERT) && COMPILER2_OR_JVMCI
1028   if (DeoptimizeObjectsALot) {
1029     // Initialize and start the object deoptimizer threads
1030     const int total_count = DeoptimizeObjectsALotThreadCountSingle + DeoptimizeObjectsALotThreadCountAll;
1031     for (int count = 0; count < total_count; count++) {
1032       Handle thread_oop = JavaThread::create_system_thread_object("Deoptimize objects a lot single mode", CHECK);
1033       jobject thread_handle = JNIHandles::make_local(THREAD, thread_oop());
1034       make_thread(deoptimizer_t, thread_handle, nullptr, nullptr, THREAD);
1035     }
1036   }
1037 #endif // defined(ASSERT) && COMPILER2_OR_JVMCI
1038 }
1039 
1040 void CompileBroker::init_training_replay() {
1041   // Ensure any exceptions lead to vm_exit_during_initialization.
1042   EXCEPTION_MARK;
1043   if (TrainingData::have_data()) {
1044     Handle thread_oop = JavaThread::create_system_thread_object("Training replay thread", CHECK);
1045     jobject thread_handle = JNIHandles::make_local(THREAD, thread_oop());
1046     make_thread(training_replay_t, thread_handle, nullptr, nullptr, THREAD);
1047   }
1048 }
1049 
1050 void CompileBroker::possibly_add_compiler_threads(JavaThread* THREAD) {
1051 
1052   int old_c2_count = 0, new_c2_count = 0, old_c1_count = 0, new_c1_count = 0;
1053   const int c2_tasks_per_thread = 2, c1_tasks_per_thread = 4;
1054 
1055   // Quick check if we already have enough compiler threads without taking the lock.
1056   // Numbers may change concurrently, so we read them again after we have the lock.
1057   if (_c2_compile_queue != nullptr) {
1058     old_c2_count = get_c2_thread_count();
1059     new_c2_count = MIN2(_c2_count, _c2_compile_queue->size() / c2_tasks_per_thread);
1060   }
1061   if (_c1_compile_queue != nullptr) {
1062     old_c1_count = get_c1_thread_count();
1063     new_c1_count = MIN2(_c1_count, _c1_compile_queue->size() / c1_tasks_per_thread);
1064   }
1065   if (new_c2_count <= old_c2_count && new_c1_count <= old_c1_count) return;
1066 
1067   // Now, we do the more expensive operations.
1068   physical_memory_size_type free_memory = 0;
1069   // Return value ignored - defaulting to 0 on failure.
1070   (void)os::free_memory(free_memory);
1071   // If SegmentedCodeCache is off, both values refer to the single heap (with type CodeBlobType::All).
1072   size_t available_cc_np = CodeCache::unallocated_capacity(CodeBlobType::MethodNonProfiled),
1073          available_cc_p  = CodeCache::unallocated_capacity(CodeBlobType::MethodProfiled);
1074 
1075   // Only attempt to start additional threads if the lock is free.
1076   if (!CompileThread_lock->try_lock()) return;
1077 
1078   if (_c2_compile_queue != nullptr) {
1079     old_c2_count = get_c2_thread_count();
1080     new_c2_count = MIN4(_c2_count,
1081         _c2_compile_queue->size() / c2_tasks_per_thread,
1082         (int)(free_memory / (200*M)),
1083         (int)(available_cc_np / (128*K)));
1084 
1085     for (int i = old_c2_count; i < new_c2_count; i++) {
1086 #if INCLUDE_JVMCI
1087       if (UseJVMCICompiler && !UseJVMCINativeLibrary && _compiler2_objects[i] == nullptr) {
1088         // Native compiler threads as used in C1/C2 can reuse the j.l.Thread objects as their
1089         // existence is completely hidden from the rest of the VM (and those compiler threads can't
1090         // call Java code to do the creation anyway).
1091         //
1092         // For pure Java JVMCI we have to create new j.l.Thread objects as they are visible and we
1093         // can see unexpected thread lifecycle transitions if we bind them to new JavaThreads.  For
1094         // native library JVMCI it's preferred to use the C1/C2 strategy as this avoids unnecessary
1095         // coupling with Java.
1096         if (!THREAD->can_call_java()) break;
1097         char name_buffer[256];
1098         os::snprintf_checked(name_buffer, sizeof(name_buffer), "%s CompilerThread%d", _compilers[1]->name(), i);
1099         Handle thread_oop;
1100         {
1101           // We have to give up the lock temporarily for the Java calls.
1102           MutexUnlocker mu(CompileThread_lock);
1103           thread_oop = JavaThread::create_system_thread_object(name_buffer, THREAD);
1104         }
1105         if (HAS_PENDING_EXCEPTION) {
1106           if (trace_compiler_threads()) {
1107             ResourceMark rm;
1108             stringStream msg;
1109             msg.print_cr("JVMCI compiler thread creation failed:");
1110             PENDING_EXCEPTION->print_on(&msg);
1111             print_compiler_threads(msg);
1112           }
1113           CLEAR_PENDING_EXCEPTION;
1114           break;
1115         }
1116         // Check if another thread has beaten us during the Java calls.
1117         if (get_c2_thread_count() != i) break;
1118         jobject thread_handle = JNIHandles::make_global(thread_oop);
1119         assert(compiler2_object(i) == nullptr, "Old one must be released!");
1120         _compiler2_objects[i] = thread_handle;
1121       }
1122 #endif
1123       guarantee(compiler2_object(i) != nullptr, "Thread oop must exist");
1124       JavaThread *ct = make_thread(compiler_t, compiler2_object(i), _c2_compile_queue, _compilers[1], THREAD);
1125       if (ct == nullptr) break;
1126       _compilers[1]->set_num_compiler_threads(i + 1);
1127       if (trace_compiler_threads()) {
1128         ResourceMark rm;
1129         ThreadsListHandle tlh;  // name() depends on the TLH.
1130         assert(tlh.includes(ct), "ct=" INTPTR_FORMAT " exited unexpectedly.", p2i(ct));
1131         stringStream msg;
1132         msg.print("Added compiler thread %s (free memory: %dMB, available non-profiled code cache: %dMB)",
1133                   ct->name(), (int)(free_memory/M), (int)(available_cc_np/M));
1134         print_compiler_threads(msg);
1135       }
1136     }
1137   }
1138 
1139   if (_c1_compile_queue != nullptr) {
1140     old_c1_count = get_c1_thread_count();
1141     new_c1_count = MIN4(_c1_count,
1142         _c1_compile_queue->size() / c1_tasks_per_thread,
1143         (int)(free_memory / (100*M)),
1144         (int)(available_cc_p / (128*K)));
1145 
1146     for (int i = old_c1_count; i < new_c1_count; i++) {
1147       JavaThread *ct = make_thread(compiler_t, compiler1_object(i), _c1_compile_queue, _compilers[0], THREAD);
1148       if (ct == nullptr) break;
1149       _compilers[0]->set_num_compiler_threads(i + 1);
1150       if (trace_compiler_threads()) {
1151         ResourceMark rm;
1152         ThreadsListHandle tlh;  // name() depends on the TLH.
1153         assert(tlh.includes(ct), "ct=" INTPTR_FORMAT " exited unexpectedly.", p2i(ct));
1154         stringStream msg;
1155         msg.print("Added compiler thread %s (free memory: %dMB, available profiled code cache: %dMB)",
1156                   ct->name(), (int)(free_memory/M), (int)(available_cc_p/M));
1157         print_compiler_threads(msg);
1158       }
1159     }
1160   }
1161 
1162   CompileThread_lock->unlock();
1163 }
1164 
1165 
1166 /**
1167  * Set the methods on the stack as on_stack so that redefine classes doesn't
1168  * reclaim them. This method is executed at a safepoint.
1169  */
1170 void CompileBroker::mark_on_stack() {
1171   assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
1172   // Since we are at a safepoint, we do not need a lock to access
1173   // the compile queues.
1174   if (_c2_compile_queue != nullptr) {
1175     _c2_compile_queue->mark_on_stack();
1176   }
1177   if (_c1_compile_queue != nullptr) {
1178     _c1_compile_queue->mark_on_stack();
1179   }
1180 }
1181 
1182 // ------------------------------------------------------------------
1183 // CompileBroker::compile_method
1184 //
1185 // Request compilation of a method.
1186 void CompileBroker::compile_method_base(const methodHandle& method,
1187                                         int osr_bci,
1188                                         int comp_level,
1189                                         int hot_count,
1190                                         CompileTask::CompileReason compile_reason,
1191                                         bool blocking,
1192                                         Thread* thread) {
1193   guarantee(!method->is_abstract(), "cannot compile abstract methods");
1194   assert(method->method_holder()->is_instance_klass(),
1195          "sanity check");
1196   assert(!method->method_holder()->is_not_initialized(),
1197          "method holder must be initialized");
1198   assert(!method->is_method_handle_intrinsic(), "do not enqueue these guys");
1199 
1200   if (CIPrintRequests) {
1201     tty->print("request: ");
1202     method->print_short_name(tty);
1203     if (osr_bci != InvocationEntryBci) {
1204       tty->print(" osr_bci: %d", osr_bci);
1205     }
1206     tty->print(" level: %d comment: %s count: %d", comp_level, CompileTask::reason_name(compile_reason), hot_count);
1207     if (hot_count > 0) {
1208       tty->print(" hot: yes");
1209     }
1210     tty->cr();
1211   }
1212 
1213   // A request has been made for compilation.  Before we do any
1214   // real work, check to see if the method has been compiled
1215   // in the meantime with a definitive result.
1216   if (compilation_is_complete(method, osr_bci, comp_level)) {
1217     return;
1218   }
1219 
1220 #ifndef PRODUCT
1221   if (osr_bci != -1 && !FLAG_IS_DEFAULT(OSROnlyBCI)) {
1222     if ((OSROnlyBCI > 0) ? (OSROnlyBCI != osr_bci) : (-OSROnlyBCI == osr_bci)) {
1223       // Positive OSROnlyBCI means only compile that bci.  Negative means don't compile that BCI.
1224       return;
1225     }
1226   }
1227 #endif
1228 
1229   // If this method is already in the compile queue, then
1230   // we do not block the current thread.
1231   if (compilation_is_in_queue(method)) {
1232     // We may want to decay our counter a bit here to prevent
1233     // multiple denied requests for compilation.  This is an
1234     // open compilation policy issue. Note: The other possibility,
1235     // in the case that this is a blocking compile request, is to have
1236     // all subsequent blocking requesters wait for completion of
1237     // ongoing compiles. Note that in this case we'll need a protocol
1238     // for freeing the associated compile tasks. [Or we could have
1239     // a single static monitor on which all these waiters sleep.]
1240     return;
1241   }
1242 
1243   // Tiered policy requires MethodCounters to exist before adding a method to
1244   // the queue. Create if we don't have them yet.
1245   method->get_method_counters(thread);
1246 
1247   // Outputs from the following MutexLocker block:
1248   CompileTask* task     = nullptr;
1249   CompileQueue* queue  = compile_queue(comp_level);
1250 
1251   // Acquire our lock.
1252   {
1253     MutexLocker locker(thread, MethodCompileQueue_lock);
1254 
1255     // Make sure the method has not slipped into the queues since
1256     // last we checked; note that those checks were "fast bail-outs".
1257     // Here we need to be more careful, see 14012000 below.
1258     if (compilation_is_in_queue(method)) {
1259       return;
1260     }
1261 
1262     // We need to check again to see if the compilation has
1263     // completed.  A previous compilation may have registered
1264     // some result.
1265     if (compilation_is_complete(method, osr_bci, comp_level)) {
1266       return;
1267     }
1268 
1269     // We now know that this compilation is not pending, complete,
1270     // or prohibited.  Assign a compile_id to this compilation
1271     // and check to see if it is in our [Start..Stop) range.
1272     int compile_id = assign_compile_id(method, osr_bci);
1273     if (compile_id == 0) {
1274       // The compilation falls outside the allowed range.
1275       return;
1276     }
1277 
1278 #if INCLUDE_JVMCI
1279     if (UseJVMCICompiler && blocking) {
1280       // Don't allow blocking compiles for requests triggered by JVMCI.
1281       if (thread->is_Compiler_thread()) {
1282         blocking = false;
1283       }
1284 
1285       // In libjvmci, JVMCI initialization should not deadlock with other threads
1286       if (!UseJVMCINativeLibrary) {
1287         // Don't allow blocking compiles if inside a class initializer or while performing class loading
1288         vframeStream vfst(JavaThread::cast(thread));
1289         for (; !vfst.at_end(); vfst.next()) {
1290           if (vfst.method()->is_static_initializer() ||
1291               (vfst.method()->method_holder()->is_subclass_of(vmClasses::ClassLoader_klass()) &&
1292                   vfst.method()->name() == vmSymbols::loadClass_name())) {
1293             blocking = false;
1294             break;
1295           }
1296         }
1297 
1298         // Don't allow blocking compilation requests to JVMCI
1299         // if JVMCI itself is not yet initialized
1300         if (!JVMCI::is_compiler_initialized() && compiler(comp_level)->is_jvmci()) {
1301           blocking = false;
1302         }
1303       }
1304 
1305       // Don't allow blocking compilation requests if we are in JVMCIRuntime::shutdown
1306       // to avoid deadlock between compiler thread(s) and threads run at shutdown
1307       // such as the DestroyJavaVM thread.
1308       if (JVMCI::in_shutdown()) {
1309         blocking = false;
1310       }
1311     }
1312 #endif // INCLUDE_JVMCI
1313 
1314     // We will enter the compilation in the queue.
1315     // 14012000: Note that this sets the queued_for_compile bits in
1316     // the target method. We can now reason that a method cannot be
1317     // queued for compilation more than once, as follows:
1318     // Before a thread queues a task for compilation, it first acquires
1319     // the compile queue lock, then checks if the method's queued bits
1320     // are set or it has already been compiled. Thus there can not be two
1321     // instances of a compilation task for the same method on the
1322     // compilation queue. Consider now the case where the compilation
1323     // thread has already removed a task for that method from the queue
1324     // and is in the midst of compiling it. In this case, the
1325     // queued_for_compile bits must be set in the method (and these
1326     // will be visible to the current thread, since the bits were set
1327     // under protection of the compile queue lock, which we hold now.
1328     // When the compilation completes, the compiler thread first sets
1329     // the compilation result and then clears the queued_for_compile
1330     // bits. Neither of these actions are protected by a barrier (or done
1331     // under the protection of a lock), so the only guarantee we have
1332     // (on machines with TSO (Total Store Order)) is that these values
1333     // will update in that order. As a result, the only combinations of
1334     // these bits that the current thread will see are, in temporal order:
1335     // <RESULT, QUEUE> :
1336     //     <0, 1> : in compile queue, but not yet compiled
1337     //     <1, 1> : compiled but queue bit not cleared
1338     //     <1, 0> : compiled and queue bit cleared
1339     // Because we first check the queue bits then check the result bits,
1340     // we are assured that we cannot introduce a duplicate task.
1341     // Note that if we did the tests in the reverse order (i.e. check
1342     // result then check queued bit), we could get the result bit before
1343     // the compilation completed, and the queue bit after the compilation
1344     // completed, and end up introducing a "duplicate" (redundant) task.
1345     // In that case, the compiler thread should first check if a method
1346     // has already been compiled before trying to compile it.
1347     // NOTE: in the event that there are multiple compiler threads and
1348     // there is de-optimization/recompilation, things will get hairy,
1349     // and in that case it's best to protect both the testing (here) of
1350     // these bits, and their updating (here and elsewhere) under a
1351     // common lock.
1352     task = create_compile_task(queue,
1353                                compile_id, method,
1354                                osr_bci, comp_level,
1355                                hot_count, compile_reason,
1356                                blocking);
1357   }
1358 
1359   if (blocking) {
1360     wait_for_completion(task);
1361   }
1362 }
1363 
1364 nmethod* CompileBroker::compile_method(const methodHandle& method, int osr_bci,
1365                                        int comp_level,
1366                                        int hot_count,
1367                                        CompileTask::CompileReason compile_reason,
1368                                        TRAPS) {
1369   // Do nothing if compilebroker is not initialized or compiles are submitted on level none
1370   if (!_initialized || comp_level == CompLevel_none) {
1371     return nullptr;
1372   }
1373 
1374   AbstractCompiler *comp = CompileBroker::compiler(comp_level);
1375   assert(comp != nullptr, "Ensure we have a compiler");
1376 
1377 #if INCLUDE_JVMCI
1378   if (comp->is_jvmci() && !JVMCI::can_initialize_JVMCI()) {
1379     // JVMCI compilation is not yet initializable.
1380     return nullptr;
1381   }
1382 #endif
1383 
1384   DirectiveSet* directive = DirectivesStack::getMatchingDirective(method, comp);
1385   // CompileBroker::compile_method can trap and can have pending async exception.
1386   nmethod* nm = CompileBroker::compile_method(method, osr_bci, comp_level, hot_count, compile_reason, directive, THREAD);
1387   DirectivesStack::release(directive);
1388   return nm;
1389 }
1390 
1391 nmethod* CompileBroker::compile_method(const methodHandle& method, int osr_bci,
1392                                          int comp_level,
1393                                          int hot_count,
1394                                          CompileTask::CompileReason compile_reason,
1395                                          DirectiveSet* directive,
1396                                          TRAPS) {
1397 
1398   // make sure arguments make sense
1399   assert(method->method_holder()->is_instance_klass(), "not an instance method");
1400   assert(osr_bci == InvocationEntryBci || (0 <= osr_bci && osr_bci < method->code_size()), "bci out of range");
1401   assert(!method->is_abstract() && (osr_bci == InvocationEntryBci || !method->is_native()), "cannot compile abstract/native methods");
1402   assert(!method->method_holder()->is_not_initialized(), "method holder must be initialized");
1403   // return quickly if possible
1404 
1405   // lock, make sure that the compilation
1406   // isn't prohibited in a straightforward way.
1407   AbstractCompiler* comp = CompileBroker::compiler(comp_level);
1408   if (comp == nullptr || compilation_is_prohibited(method, osr_bci, comp_level, directive->ExcludeOption)) {
1409     return nullptr;
1410   }
1411 
1412   if (osr_bci == InvocationEntryBci) {
1413     // standard compilation
1414     nmethod* method_code = method->code();
1415     if (method_code != nullptr) {
1416       if (compilation_is_complete(method, osr_bci, comp_level)) {
1417         return method_code;
1418       }
1419     }
1420     if (method->is_not_compilable(comp_level)) {
1421       return nullptr;
1422     }
1423   } else {
1424     // osr compilation
1425     // We accept a higher level osr method
1426     nmethod* nm = method->lookup_osr_nmethod_for(osr_bci, comp_level, false);
1427     if (nm != nullptr) return nm;
1428     if (method->is_not_osr_compilable(comp_level)) return nullptr;
1429   }
1430 
1431   assert(!HAS_PENDING_EXCEPTION, "No exception should be present");
1432   // some prerequisites that are compiler specific
1433   if (comp->is_c2() || comp->is_jvmci()) {
1434     InternalOOMEMark iom(THREAD);
1435     method->constants()->resolve_string_constants(CHECK_AND_CLEAR_NONASYNC_NULL);
1436     // Resolve all classes seen in the signature of the method
1437     // we are compiling.
1438     Method::load_signature_classes(method, CHECK_AND_CLEAR_NONASYNC_NULL);
1439   }
1440 
1441   // If the method is native, do the lookup in the thread requesting
1442   // the compilation. Native lookups can load code, which is not
1443   // permitted during compilation.
1444   //
1445   // Note: A native method implies non-osr compilation which is
1446   //       checked with an assertion at the entry of this method.
1447   if (method->is_native() && !method->is_method_handle_intrinsic()) {
1448     address adr = NativeLookup::lookup(method, THREAD);
1449     if (HAS_PENDING_EXCEPTION) {
1450       // In case of an exception looking up the method, we just forget
1451       // about it. The interpreter will kick-in and throw the exception.
1452       method->set_not_compilable("NativeLookup::lookup failed"); // implies is_not_osr_compilable()
1453       CLEAR_PENDING_EXCEPTION;
1454       return nullptr;
1455     }
1456     assert(method->has_native_function(), "must have native code by now");
1457   }
1458 
1459   // RedefineClasses() has replaced this method; just return
1460   if (method->is_old()) {
1461     return nullptr;
1462   }
1463 
1464   // JVMTI -- post_compile_event requires jmethod_id() that may require
1465   // a lock the compiling thread can not acquire. Prefetch it here.
1466   if (JvmtiExport::should_post_compiled_method_load()) {
1467     method->jmethod_id();
1468   }
1469 
1470   // do the compilation
1471   if (method->is_native()) {
1472     if (!PreferInterpreterNativeStubs || method->is_method_handle_intrinsic()) {
1473       // To properly handle the appendix argument for out-of-line calls we are using a small trampoline that
1474       // pops off the appendix argument and jumps to the target (see gen_special_dispatch in SharedRuntime).
1475       //
1476       // Since normal compiled-to-compiled calls are not able to handle such a thing we MUST generate an adapter
1477       // in this case.  If we can't generate one and use it we can not execute the out-of-line method handle calls.
1478       AdapterHandlerLibrary::create_native_wrapper(method);
1479     } else {
1480       return nullptr;
1481     }
1482   } else {
1483     // If the compiler is shut off due to code cache getting full
1484     // fail out now so blocking compiles dont hang the java thread
1485     if (!should_compile_new_jobs()) {
1486       return nullptr;
1487     }
1488     bool is_blocking = !directive->BackgroundCompilationOption || ReplayCompiles;
1489     compile_method_base(method, osr_bci, comp_level, hot_count, compile_reason, is_blocking, THREAD);
1490   }
1491 
1492   // return requested nmethod
1493   // We accept a higher level osr method
1494   if (osr_bci == InvocationEntryBci) {
1495     return method->code();
1496   }
1497   return method->lookup_osr_nmethod_for(osr_bci, comp_level, false);
1498 }
1499 
1500 
1501 // ------------------------------------------------------------------
1502 // CompileBroker::compilation_is_complete
1503 //
1504 // See if compilation of this method is already complete.
1505 bool CompileBroker::compilation_is_complete(const methodHandle& method,
1506                                             int                 osr_bci,
1507                                             int                 comp_level) {
1508   bool is_osr = (osr_bci != standard_entry_bci);
1509   if (is_osr) {
1510     if (method->is_not_osr_compilable(comp_level)) {
1511       return true;
1512     } else {
1513       nmethod* result = method->lookup_osr_nmethod_for(osr_bci, comp_level, true);
1514       return (result != nullptr);
1515     }
1516   } else {
1517     if (method->is_not_compilable(comp_level)) {
1518       return true;
1519     } else {
1520       nmethod* result = method->code();
1521       if (result == nullptr) return false;
1522       return comp_level == result->comp_level();
1523     }
1524   }
1525 }
1526 
1527 
1528 /**
1529  * See if this compilation is already requested.
1530  *
1531  * Implementation note: there is only a single "is in queue" bit
1532  * for each method.  This means that the check below is overly
1533  * conservative in the sense that an osr compilation in the queue
1534  * will block a normal compilation from entering the queue (and vice
1535  * versa).  This can be remedied by a full queue search to disambiguate
1536  * cases.  If it is deemed profitable, this may be done.
1537  */
1538 bool CompileBroker::compilation_is_in_queue(const methodHandle& method) {
1539   return method->queued_for_compilation();
1540 }
1541 
1542 // ------------------------------------------------------------------
1543 // CompileBroker::compilation_is_prohibited
1544 //
1545 // See if this compilation is not allowed.
1546 bool CompileBroker::compilation_is_prohibited(const methodHandle& method, int osr_bci, int comp_level, bool excluded) {
1547   bool is_native = method->is_native();
1548   // Some compilers may not support the compilation of natives.
1549   AbstractCompiler *comp = compiler(comp_level);
1550   if (is_native && (!CICompileNatives || comp == nullptr)) {
1551     method->set_not_compilable_quietly("native methods not supported", comp_level);
1552     return true;
1553   }
1554 
1555   bool is_osr = (osr_bci != standard_entry_bci);
1556   // Some compilers may not support on stack replacement.
1557   if (is_osr && (!CICompileOSR || comp == nullptr)) {
1558     method->set_not_osr_compilable("OSR not supported", comp_level);
1559     return true;
1560   }
1561 
1562   // The method may be explicitly excluded by the user.
1563   double scale;
1564   if (excluded || (CompilerOracle::has_option_value(method, CompileCommandEnum::CompileThresholdScaling, scale) && scale == 0)) {
1565     bool quietly = CompilerOracle::be_quiet();
1566     if (PrintCompilation && !quietly) {
1567       // This does not happen quietly...
1568       ResourceMark rm;
1569       tty->print("### Excluding %s:%s",
1570                  method->is_native() ? "generation of native wrapper" : "compile",
1571                  (method->is_static() ? " static" : ""));
1572       method->print_short_name(tty);
1573       tty->cr();
1574     }
1575     method->set_not_compilable("excluded by CompileCommand", comp_level, !quietly);
1576   }
1577 
1578   return false;
1579 }
1580 
1581 /**
1582  * Generate serialized IDs for compilation requests. If certain debugging flags are used
1583  * and the ID is not within the specified range, the method is not compiled and 0 is returned.
1584  * The function also allows to generate separate compilation IDs for OSR compilations.
1585  */
1586 int CompileBroker::assign_compile_id(const methodHandle& method, int osr_bci) {
1587 #ifdef ASSERT
1588   bool is_osr = (osr_bci != standard_entry_bci);
1589   int id;
1590   if (method->is_native()) {
1591     assert(!is_osr, "can't be osr");
1592     // Adapters, native wrappers and method handle intrinsics
1593     // should be generated always.
1594     return AtomicAccess::add(CICountNative ? &_native_compilation_id : &_compilation_id, 1);
1595   } else if (CICountOSR && is_osr) {
1596     id = AtomicAccess::add(&_osr_compilation_id, 1);
1597     if (CIStartOSR <= id && id < CIStopOSR) {
1598       return id;
1599     }
1600   } else {
1601     id = AtomicAccess::add(&_compilation_id, 1);
1602     if (CIStart <= id && id < CIStop) {
1603       return id;
1604     }
1605   }
1606 
1607   // Method was not in the appropriate compilation range.
1608   method->set_not_compilable_quietly("Not in requested compile id range");
1609   return 0;
1610 #else
1611   // CICountOSR is a develop flag and set to 'false' by default. In a product built,
1612   // only _compilation_id is incremented.
1613   return AtomicAccess::add(&_compilation_id, 1);
1614 #endif
1615 }
1616 
1617 // ------------------------------------------------------------------
1618 // CompileBroker::assign_compile_id_unlocked
1619 //
1620 // Public wrapper for assign_compile_id that acquires the needed locks
1621 int CompileBroker::assign_compile_id_unlocked(Thread* thread, const methodHandle& method, int osr_bci) {
1622   MutexLocker locker(thread, MethodCompileQueue_lock);
1623   return assign_compile_id(method, osr_bci);
1624 }
1625 
1626 // ------------------------------------------------------------------
1627 // CompileBroker::create_compile_task
1628 //
1629 // Create a CompileTask object representing the current request for
1630 // compilation.  Add this task to the queue.
1631 CompileTask* CompileBroker::create_compile_task(CompileQueue*       queue,
1632                                                 int                 compile_id,
1633                                                 const methodHandle& method,
1634                                                 int                 osr_bci,
1635                                                 int                 comp_level,
1636                                                 int                 hot_count,
1637                                                 CompileTask::CompileReason compile_reason,
1638                                                 bool                blocking) {
1639   CompileTask* new_task = new CompileTask(compile_id, method, osr_bci, comp_level,
1640                                           hot_count, compile_reason, blocking);
1641   queue->add(new_task);
1642   return new_task;
1643 }
1644 
1645 #if INCLUDE_JVMCI
1646 // The number of milliseconds to wait before checking if
1647 // JVMCI compilation has made progress.
1648 static const long JVMCI_COMPILATION_PROGRESS_WAIT_TIMESLICE = 1000;
1649 
1650 // The number of JVMCI compilation progress checks that must fail
1651 // before unblocking a thread waiting for a blocking compilation.
1652 static const int JVMCI_COMPILATION_PROGRESS_WAIT_ATTEMPTS = 10;
1653 
1654 /**
1655  * Waits for a JVMCI compiler to complete a given task. This thread
1656  * waits until either the task completes or it sees no JVMCI compilation
1657  * progress for N consecutive milliseconds where N is
1658  * JVMCI_COMPILATION_PROGRESS_WAIT_TIMESLICE *
1659  * JVMCI_COMPILATION_PROGRESS_WAIT_ATTEMPTS.
1660  *
1661  * @return true if this thread needs to delete the task
1662  */
1663 bool CompileBroker::wait_for_jvmci_completion(JVMCICompiler* jvmci, CompileTask* task, JavaThread* thread) {
1664   assert(UseJVMCICompiler, "sanity");
1665   MonitorLocker ml(thread, CompileTaskWait_lock);
1666   int progress_wait_attempts = 0;
1667   jint thread_jvmci_compilation_ticks = 0;
1668   jint global_jvmci_compilation_ticks = jvmci->global_compilation_ticks();
1669   while (!task->is_complete() && !is_compilation_disabled_forever() &&
1670          ml.wait(JVMCI_COMPILATION_PROGRESS_WAIT_TIMESLICE)) {
1671     JVMCICompileState* jvmci_compile_state = task->blocking_jvmci_compile_state();
1672 
1673     bool progress;
1674     if (jvmci_compile_state != nullptr) {
1675       jint ticks = jvmci_compile_state->compilation_ticks();
1676       progress = (ticks - thread_jvmci_compilation_ticks) != 0;
1677       JVMCI_event_1("waiting on compilation %d [ticks=%d]", task->compile_id(), ticks);
1678       thread_jvmci_compilation_ticks = ticks;
1679     } else {
1680       // Still waiting on JVMCI compiler queue. This thread may be holding a lock
1681       // that all JVMCI compiler threads are blocked on. We use the global JVMCI
1682       // compilation ticks to determine whether JVMCI compilation
1683       // is still making progress through the JVMCI compiler queue.
1684       jint ticks = jvmci->global_compilation_ticks();
1685       progress = (ticks - global_jvmci_compilation_ticks) != 0;
1686       JVMCI_event_1("waiting on compilation %d to be queued [ticks=%d]", task->compile_id(), ticks);
1687       global_jvmci_compilation_ticks = ticks;
1688     }
1689 
1690     if (!progress) {
1691       if (++progress_wait_attempts == JVMCI_COMPILATION_PROGRESS_WAIT_ATTEMPTS) {
1692         if (PrintCompilation) {
1693           task->print(tty, "wait for blocking compilation timed out");
1694         }
1695         JVMCI_event_1("waiting on compilation %d timed out", task->compile_id());
1696         break;
1697       }
1698     } else {
1699       progress_wait_attempts = 0;
1700     }
1701   }
1702   task->clear_waiter();
1703   return task->is_complete();
1704 }
1705 #endif
1706 
1707 /**
1708  *  Wait for the compilation task to complete.
1709  */
1710 void CompileBroker::wait_for_completion(CompileTask* task) {
1711   if (CIPrintCompileQueue) {
1712     ttyLocker ttyl;
1713     tty->print_cr("BLOCKING FOR COMPILE");
1714   }
1715 
1716   assert(task->is_blocking(), "can only wait on blocking task");
1717 
1718   JavaThread* thread = JavaThread::current();
1719 
1720   methodHandle method(thread, task->method());
1721   bool free_task;
1722 #if INCLUDE_JVMCI
1723   AbstractCompiler* comp = compiler(task->comp_level());
1724   if (!UseJVMCINativeLibrary && comp->is_jvmci() && !task->should_wait_for_compilation()) {
1725     // It may return before compilation is completed.
1726     // Note that libjvmci should not pre-emptively unblock
1727     // a thread waiting for a compilation as it does not call
1728     // Java code and so is not deadlock prone like jarjvmci.
1729     free_task = wait_for_jvmci_completion((JVMCICompiler*) comp, task, thread);
1730   } else
1731 #endif
1732   {
1733     free_task = true;
1734     // Wait until the task is complete or compilation is shut down.
1735     MonitorLocker ml(thread, CompileTaskWait_lock);
1736     while (!task->is_complete() && !is_compilation_disabled_forever()) {
1737       ml.wait();
1738     }
1739   }
1740 
1741   // It is harmless to check this status without the lock, because
1742   // completion is a stable property.
1743   if (!task->is_complete()) {
1744     // Task is not complete, likely because we are exiting for compilation
1745     // shutdown. The task can still be reached through the queue, or executed
1746     // by some compiler thread. There is no coordination with either MCQ lock
1747     // holders or compilers, therefore we cannot delete the task.
1748     //
1749     // This will leave task allocated, which leaks it. At this (degraded) point,
1750     // it is less risky to abandon the task, rather than attempting a more
1751     // complicated deletion protocol.
1752     free_task = false;
1753   }
1754 
1755   if (free_task) {
1756     assert(task->is_complete(), "Compilation should have completed");
1757     assert(task->next() == nullptr && task->prev() == nullptr,
1758            "Completed task should not be in the queue");
1759 
1760     // By convention, the waiter is responsible for deleting a
1761     // blocking CompileTask. Since there is only one waiter ever
1762     // waiting on a CompileTask, we know that no one else will
1763     // be using this CompileTask; we can delete it.
1764     delete task;
1765   }
1766 }
1767 
1768 void CompileBroker::wait_for_no_active_tasks() {
1769   CompileTask::wait_for_no_active_tasks();
1770 }
1771 
1772 /**
1773  * Initialize compiler thread(s) + compiler object(s). The postcondition
1774  * of this function is that the compiler runtimes are initialized and that
1775  * compiler threads can start compiling.
1776  */
1777 bool CompileBroker::init_compiler_runtime() {
1778   CompilerThread* thread = CompilerThread::current();
1779   AbstractCompiler* comp = thread->compiler();
1780   // Final sanity check - the compiler object must exist
1781   guarantee(comp != nullptr, "Compiler object must exist");
1782 
1783   {
1784     // Must switch to native to allocate ci_env
1785     ThreadToNativeFromVM ttn(thread);
1786     ciEnv ci_env((CompileTask*)nullptr);
1787     // Cache Jvmti state
1788     ci_env.cache_jvmti_state();
1789     // Cache DTrace flags
1790     ci_env.cache_dtrace_flags();
1791 
1792     // Switch back to VM state to do compiler initialization
1793     ThreadInVMfromNative tv(thread);
1794 
1795     // Perform per-thread and global initializations
1796     comp->initialize();
1797   }
1798 
1799   if (comp->is_failed()) {
1800     disable_compilation_forever();
1801     // If compiler initialization failed, no compiler thread that is specific to a
1802     // particular compiler runtime will ever start to compile methods.
1803     shutdown_compiler_runtime(comp, thread);
1804     return false;
1805   }
1806 
1807   // C1 specific check
1808   if (comp->is_c1() && (thread->get_buffer_blob() == nullptr)) {
1809     warning("Initialization of %s thread failed (no space to run compilers)", thread->name());
1810     return false;
1811   }
1812 
1813   return true;
1814 }
1815 
1816 void CompileBroker::free_buffer_blob_if_allocated(CompilerThread* thread) {
1817   BufferBlob* blob = thread->get_buffer_blob();
1818   if (blob != nullptr) {
1819     blob->purge();
1820     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1821     CodeCache::free(blob);
1822   }
1823 }
1824 
1825 /**
1826  * If C1 and/or C2 initialization failed, we shut down all compilation.
1827  * We do this to keep things simple. This can be changed if it ever turns
1828  * out to be a problem.
1829  */
1830 void CompileBroker::shutdown_compiler_runtime(AbstractCompiler* comp, CompilerThread* thread) {
1831   free_buffer_blob_if_allocated(thread);
1832 
1833   if (comp->should_perform_shutdown()) {
1834     // There are two reasons for shutting down the compiler
1835     // 1) compiler runtime initialization failed
1836     // 2) The code cache is full and the following flag is set: -XX:-UseCodeCacheFlushing
1837     warning("%s initialization failed. Shutting down all compilers", comp->name());
1838 
1839     // Only one thread per compiler runtime object enters here
1840     // Set state to shut down
1841     comp->set_shut_down();
1842 
1843     // Delete all queued compilation tasks to make compiler threads exit faster.
1844     if (_c1_compile_queue != nullptr) {
1845       _c1_compile_queue->delete_all();
1846     }
1847 
1848     if (_c2_compile_queue != nullptr) {
1849       _c2_compile_queue->delete_all();
1850     }
1851 
1852     // Set flags so that we continue execution with using interpreter only.
1853     UseCompiler    = false;
1854     UseInterpreter = true;
1855 
1856     // We could delete compiler runtimes also. However, there are references to
1857     // the compiler runtime(s) (e.g.,  nmethod::is_compiled_by_c1()) which then
1858     // fail. This can be done later if necessary.
1859   }
1860 }
1861 
1862 /**
1863  * Helper function to create new or reuse old CompileLog.
1864  */
1865 CompileLog* CompileBroker::get_log(CompilerThread* ct) {
1866   if (!LogCompilation) return nullptr;
1867 
1868   AbstractCompiler *compiler = ct->compiler();
1869   bool c1 = compiler->is_c1();
1870   jobject* compiler_objects = c1 ? _compiler1_objects : _compiler2_objects;
1871   assert(compiler_objects != nullptr, "must be initialized at this point");
1872   CompileLog** logs = c1 ? _compiler1_logs : _compiler2_logs;
1873   assert(logs != nullptr, "must be initialized at this point");
1874   int count = c1 ? _c1_count : _c2_count;
1875 
1876   // Find Compiler number by its threadObj.
1877   oop compiler_obj = ct->threadObj();
1878   int compiler_number = 0;
1879   bool found = false;
1880   for (; compiler_number < count; compiler_number++) {
1881     if (JNIHandles::resolve_non_null(compiler_objects[compiler_number]) == compiler_obj) {
1882       found = true;
1883       break;
1884     }
1885   }
1886   assert(found, "Compiler must exist at this point");
1887 
1888   // Determine pointer for this thread's log.
1889   CompileLog** log_ptr = &logs[compiler_number];
1890 
1891   // Return old one if it exists.
1892   CompileLog* log = *log_ptr;
1893   if (log != nullptr) {
1894     ct->init_log(log);
1895     return log;
1896   }
1897 
1898   // Create a new one and remember it.
1899   init_compiler_thread_log();
1900   log = ct->log();
1901   *log_ptr = log;
1902   return log;
1903 }
1904 
1905 // ------------------------------------------------------------------
1906 // CompileBroker::compiler_thread_loop
1907 //
1908 // The main loop run by a CompilerThread.
1909 void CompileBroker::compiler_thread_loop() {
1910   CompilerThread* thread = CompilerThread::current();
1911   CompileQueue* queue = thread->queue();
1912   // For the thread that initializes the ciObjectFactory
1913   // this resource mark holds all the shared objects
1914   ResourceMark rm;
1915 
1916   // First thread to get here will initialize the compiler interface
1917 
1918   {
1919     ASSERT_IN_VM;
1920     MutexLocker only_one (thread, CompileThread_lock);
1921     if (!ciObjectFactory::is_initialized()) {
1922       ciObjectFactory::initialize();
1923     }
1924   }
1925 
1926   // Open a log.
1927   CompileLog* log = get_log(thread);
1928   if (log != nullptr) {
1929     log->begin_elem("start_compile_thread name='%s' thread='%zu' process='%d'",
1930                     thread->name(),
1931                     os::current_thread_id(),
1932                     os::current_process_id());
1933     log->stamp();
1934     log->end_elem();
1935   }
1936 
1937   if (!thread->init_compilation_timeout()) {
1938     return;
1939   }
1940 
1941   // If compiler thread/runtime initialization fails, exit the compiler thread
1942   if (!init_compiler_runtime()) {
1943     return;
1944   }
1945 
1946   thread->start_idle_timer();
1947 
1948   // Poll for new compilation tasks as long as the JVM runs. Compilation
1949   // should only be disabled if something went wrong while initializing the
1950   // compiler runtimes. This, in turn, should not happen. The only known case
1951   // when compiler runtime initialization fails is if there is not enough free
1952   // space in the code cache to generate the necessary stubs, etc.
1953   while (!is_compilation_disabled_forever()) {
1954     // We need this HandleMark to avoid leaking VM handles.
1955     HandleMark hm(thread);
1956 
1957     CompileTask* task = queue->get(thread);
1958     if (task == nullptr) {
1959       if (UseDynamicNumberOfCompilerThreads) {
1960         // Access compiler_count under lock to enforce consistency.
1961         MutexLocker only_one(CompileThread_lock);
1962         if (can_remove(thread, true)) {
1963           if (trace_compiler_threads()) {
1964             ResourceMark rm;
1965             stringStream msg;
1966             msg.print("Removing compiler thread %s after " JLONG_FORMAT " ms idle time",
1967                       thread->name(), thread->idle_time_millis());
1968             print_compiler_threads(msg);
1969           }
1970 
1971           // Notify compiler that the compiler thread is about to stop
1972           thread->compiler()->stopping_compiler_thread(thread);
1973 
1974           free_buffer_blob_if_allocated(thread);
1975           return; // Stop this thread.
1976         }
1977       }
1978     } else {
1979       // Assign the task to the current thread.  Mark this compilation
1980       // thread as active for the profiler.
1981       // CompileTaskWrapper also keeps the Method* from being deallocated if redefinition
1982       // occurs after fetching the compile task off the queue.
1983       CompileTaskWrapper ctw(task);
1984       methodHandle method(thread, task->method());
1985 
1986       // Never compile a method if breakpoints are present in it
1987       if (method()->number_of_breakpoints() == 0) {
1988         // Compile the method.
1989         if ((UseCompiler || AlwaysCompileLoopMethods) && CompileBroker::should_compile_new_jobs()) {
1990           invoke_compiler_on_method(task);
1991           thread->start_idle_timer();
1992         } else {
1993           // After compilation is disabled, remove remaining methods from queue
1994           method->clear_queued_for_compilation();
1995           task->set_failure_reason("compilation is disabled");
1996         }
1997       } else {
1998         task->set_failure_reason("breakpoints are present");
1999       }
2000 
2001       if (UseDynamicNumberOfCompilerThreads) {
2002         possibly_add_compiler_threads(thread);
2003         assert(!thread->has_pending_exception(), "should have been handled");
2004       }
2005     }
2006   }
2007 
2008   // Shut down compiler runtime
2009   shutdown_compiler_runtime(thread->compiler(), thread);
2010 }
2011 
2012 // ------------------------------------------------------------------
2013 // CompileBroker::init_compiler_thread_log
2014 //
2015 // Set up state required by +LogCompilation.
2016 void CompileBroker::init_compiler_thread_log() {
2017     CompilerThread* thread = CompilerThread::current();
2018     char  file_name[4*K];
2019     FILE* fp = nullptr;
2020     intx thread_id = os::current_thread_id();
2021     for (int try_temp_dir = 1; try_temp_dir >= 0; try_temp_dir--) {
2022       const char* dir = (try_temp_dir ? os::get_temp_directory() : nullptr);
2023       if (dir == nullptr) {
2024         jio_snprintf(file_name, sizeof(file_name), "hs_c%zu_pid%u.log",
2025                      thread_id, os::current_process_id());
2026       } else {
2027         jio_snprintf(file_name, sizeof(file_name),
2028                      "%s%shs_c%zu_pid%u.log", dir,
2029                      os::file_separator(), thread_id, os::current_process_id());
2030       }
2031 
2032       fp = os::fopen(file_name, "wt");
2033       if (fp != nullptr) {
2034         if (LogCompilation && Verbose) {
2035           tty->print_cr("Opening compilation log %s", file_name);
2036         }
2037         CompileLog* log = new(mtCompiler) CompileLog(file_name, fp, thread_id);
2038         if (log == nullptr) {
2039           fclose(fp);
2040           return;
2041         }
2042         thread->init_log(log);
2043 
2044         if (xtty != nullptr) {
2045           ttyLocker ttyl;
2046           // Record any per thread log files
2047           xtty->elem("thread_logfile thread='%zd' filename='%s'", thread_id, file_name);
2048         }
2049         return;
2050       }
2051     }
2052     warning("Cannot open log file: %s", file_name);
2053 }
2054 
2055 void CompileBroker::log_metaspace_failure() {
2056   const char* message = "some methods may not be compiled because metaspace "
2057                         "is out of memory";
2058   if (CompilationLog::log() != nullptr) {
2059     CompilationLog::log()->log_metaspace_failure(message);
2060   }
2061   if (PrintCompilation) {
2062     tty->print_cr("COMPILE PROFILING SKIPPED: %s", message);
2063   }
2064 }
2065 
2066 
2067 // ------------------------------------------------------------------
2068 // CompileBroker::set_should_block
2069 //
2070 // Set _should_block.
2071 // Call this from the VM, with Threads_lock held and a safepoint requested.
2072 void CompileBroker::set_should_block() {
2073   assert(Threads_lock->owner() == Thread::current(), "must have threads lock");
2074   assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint already");
2075 #ifndef PRODUCT
2076   if (PrintCompilation && (Verbose || WizardMode))
2077     tty->print_cr("notifying compiler thread pool to block");
2078 #endif
2079   _should_block = true;
2080 }
2081 
2082 // ------------------------------------------------------------------
2083 // CompileBroker::maybe_block
2084 //
2085 // Call this from the compiler at convenient points, to poll for _should_block.
2086 void CompileBroker::maybe_block() {
2087   if (_should_block) {
2088 #ifndef PRODUCT
2089     if (PrintCompilation && (Verbose || WizardMode))
2090       tty->print_cr("compiler thread " INTPTR_FORMAT " poll detects block request", p2i(Thread::current()));
2091 #endif
2092     // If we are executing a task during the request to block, report the task
2093     // before disappearing.
2094     CompilerThread* thread = CompilerThread::current();
2095     if (thread != nullptr) {
2096       CompileTask* task = thread->task();
2097       if (task != nullptr) {
2098         if (PrintCompilation) {
2099           task->print(tty, "blocked");
2100         }
2101         task->print_ul("blocked");
2102       }
2103     }
2104     // Go to VM state and block for final VM shutdown safepoint.
2105     ThreadInVMfromNative tivfn(JavaThread::current());
2106     assert(false, "Should never unblock from TIVNM entry");
2107   }
2108 }
2109 
2110 // wrapper for CodeCache::print_summary()
2111 static void codecache_print(bool detailed)
2112 {
2113   stringStream s;
2114   // Dump code cache  into a buffer before locking the tty,
2115   {
2116     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
2117     CodeCache::print_summary(&s, detailed);
2118   }
2119   ttyLocker ttyl;
2120   tty->print("%s", s.freeze());
2121 }
2122 
2123 // wrapper for CodeCache::print_summary() using outputStream
2124 static void codecache_print(outputStream* out, bool detailed) {
2125   stringStream s;
2126 
2127   // Dump code cache into a buffer
2128   {
2129     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
2130     CodeCache::print_summary(&s, detailed);
2131   }
2132 
2133   char* remaining_log = s.as_string();
2134   while (*remaining_log != '\0') {
2135     char* eol = strchr(remaining_log, '\n');
2136     if (eol == nullptr) {
2137       out->print_cr("%s", remaining_log);
2138       remaining_log = remaining_log + strlen(remaining_log);
2139     } else {
2140       *eol = '\0';
2141       out->print_cr("%s", remaining_log);
2142       remaining_log = eol + 1;
2143     }
2144   }
2145 }
2146 
2147 void CompileBroker::handle_compile_error(CompilerThread* thread, CompileTask* task, ciEnv* ci_env,
2148                                          int compilable, const char* failure_reason) {
2149   if (!AbortVMOnCompilationFailure) {
2150     return;
2151   }
2152   if (compilable == ciEnv::MethodCompilable_not_at_tier) {
2153     fatal("Not compilable at tier %d: %s", task->comp_level(), failure_reason);
2154   }
2155   if (compilable == ciEnv::MethodCompilable_never) {
2156     fatal("Never compilable: %s", failure_reason);
2157   }
2158 }
2159 
2160 static void post_compilation_event(EventCompilation& event, CompileTask* task) {
2161   assert(task != nullptr, "invariant");
2162   CompilerEvent::CompilationEvent::post(event,
2163                                         task->compile_id(),
2164                                         task->compiler()->type(),
2165                                         task->method(),
2166                                         task->comp_level(),
2167                                         task->is_success(),
2168                                         task->osr_bci() != CompileBroker::standard_entry_bci,
2169                                         task->nm_total_size(),
2170                                         task->num_inlined_bytecodes(),
2171                                         task->arena_bytes());
2172 }
2173 
2174 int DirectivesStack::_depth = 0;
2175 CompilerDirectives* DirectivesStack::_top = nullptr;
2176 CompilerDirectives* DirectivesStack::_bottom = nullptr;
2177 
2178 // Acquires Compilation_lock and waits for it to be notified
2179 // as long as WhiteBox::compilation_locked is true.
2180 static void whitebox_lock_compilation() {
2181   MonitorLocker locker(Compilation_lock, Mutex::_no_safepoint_check_flag);
2182   while (WhiteBox::compilation_locked) {
2183     locker.wait();
2184   }
2185 }
2186 
2187 // ------------------------------------------------------------------
2188 // CompileBroker::invoke_compiler_on_method
2189 //
2190 // Compile a method.
2191 //
2192 void CompileBroker::invoke_compiler_on_method(CompileTask* task) {
2193   task->print_ul();
2194   elapsedTimer time;
2195 
2196   DirectiveSet* directive = task->directive();
2197   if (directive->PrintCompilationOption) {
2198     ResourceMark rm;
2199     task->print_tty();
2200   }
2201 
2202   CompilerThread* thread = CompilerThread::current();
2203   ResourceMark rm(thread);
2204 
2205   if (CompilationLog::log() != nullptr) {
2206     CompilationLog::log()->log_compile(thread, task);
2207   }
2208 
2209   // Common flags.
2210   int compile_id = task->compile_id();
2211   int osr_bci = task->osr_bci();
2212   bool is_osr = (osr_bci != standard_entry_bci);
2213   bool should_log = (thread->log() != nullptr);
2214   bool should_break = false;
2215   const int task_level = task->comp_level();
2216   AbstractCompiler* comp = task->compiler();
2217   {
2218     // create the handle inside it's own block so it can't
2219     // accidentally be referenced once the thread transitions to
2220     // native.  The NoHandleMark before the transition should catch
2221     // any cases where this occurs in the future.
2222     methodHandle method(thread, task->method());
2223 
2224     assert(!method->is_native(), "no longer compile natives");
2225 
2226     // Update compile information when using perfdata.
2227     if (UsePerfData) {
2228       update_compile_perf_data(thread, method, is_osr);
2229     }
2230 
2231     DTRACE_METHOD_COMPILE_BEGIN_PROBE(method, compiler_name(task_level));
2232   }
2233 
2234   should_break = directive->BreakAtCompileOption || task->check_break_at_flags();
2235   if (should_log && !directive->LogOption) {
2236     should_log = false;
2237   }
2238 
2239   // Allocate a new set of JNI handles.
2240   JNIHandleMark jhm(thread);
2241   Method* target_handle = task->method();
2242   int compilable = ciEnv::MethodCompilable;
2243   const char* failure_reason = nullptr;
2244   bool failure_reason_on_C_heap = false;
2245   const char* retry_message = nullptr;
2246 
2247 #if INCLUDE_JVMCI
2248   if (UseJVMCICompiler && comp != nullptr && comp->is_jvmci()) {
2249     JVMCICompiler* jvmci = (JVMCICompiler*) comp;
2250 
2251     TraceTime t1("compilation", &time);
2252     EventCompilation event;
2253     JVMCICompileState compile_state(task, jvmci);
2254     JVMCIRuntime *runtime = nullptr;
2255 
2256     if (JVMCI::in_shutdown()) {
2257       failure_reason = "in JVMCI shutdown";
2258       retry_message = "not retryable";
2259       compilable = ciEnv::MethodCompilable_never;
2260     } else if (compile_state.target_method_is_old()) {
2261       // Skip redefined methods
2262       failure_reason = "redefined method";
2263       retry_message = "not retryable";
2264       compilable = ciEnv::MethodCompilable_never;
2265     } else {
2266       JVMCIEnv env(thread, &compile_state, __FILE__, __LINE__);
2267       if (env.init_error() != JNI_OK) {
2268         const char* msg = env.init_error_msg();
2269         failure_reason = os::strdup(err_msg("Error attaching to libjvmci (err: %d, %s)",
2270                                     env.init_error(), msg == nullptr ? "unknown" : msg), mtJVMCI);
2271         bool reason_on_C_heap = true;
2272         // In case of JNI_ENOMEM, there's a good chance a subsequent attempt to create libjvmci or attach to it
2273         // might succeed. Other errors most likely indicate a non-recoverable error in the JVMCI runtime.
2274         bool retryable = env.init_error() == JNI_ENOMEM;
2275         compile_state.set_failure(retryable, failure_reason, reason_on_C_heap);
2276       }
2277       if (failure_reason == nullptr) {
2278         if (WhiteBoxAPI && WhiteBox::compilation_locked) {
2279           // Must switch to native to block
2280           ThreadToNativeFromVM ttn(thread);
2281           whitebox_lock_compilation();
2282         }
2283         methodHandle method(thread, target_handle);
2284         runtime = env.runtime();
2285         runtime->compile_method(&env, jvmci, method, osr_bci);
2286 
2287         failure_reason = compile_state.failure_reason();
2288         failure_reason_on_C_heap = compile_state.failure_reason_on_C_heap();
2289         if (!compile_state.retryable()) {
2290           retry_message = "not retryable";
2291           compilable = ciEnv::MethodCompilable_not_at_tier;
2292         }
2293         if (!task->is_success()) {
2294           assert(failure_reason != nullptr, "must specify failure_reason");
2295         }
2296       }
2297     }
2298     if (!task->is_success() && !JVMCI::in_shutdown()) {
2299       handle_compile_error(thread, task, nullptr, compilable, failure_reason);
2300     }
2301     if (event.should_commit()) {
2302       post_compilation_event(event, task);
2303     }
2304 
2305     if (runtime != nullptr) {
2306       runtime->post_compile(thread);
2307     }
2308   } else
2309 #endif // INCLUDE_JVMCI
2310   {
2311     NoHandleMark  nhm;
2312     ThreadToNativeFromVM ttn(thread);
2313 
2314     ciEnv ci_env(task);
2315     if (should_break) {
2316       ci_env.set_break_at_compile(true);
2317     }
2318     if (should_log) {
2319       ci_env.set_log(thread->log());
2320     }
2321     assert(thread->env() == &ci_env, "set by ci_env");
2322     // The thread-env() field is cleared in ~CompileTaskWrapper.
2323 
2324     // Cache Jvmti state
2325     bool method_is_old = ci_env.cache_jvmti_state();
2326 
2327     // Skip redefined methods
2328     if (method_is_old) {
2329       ci_env.record_method_not_compilable("redefined method", true);
2330     }
2331 
2332     // Cache DTrace flags
2333     ci_env.cache_dtrace_flags();
2334 
2335     ciMethod* target = ci_env.get_method_from_handle(target_handle);
2336 
2337     TraceTime t1("compilation", &time);
2338     EventCompilation event;
2339 
2340     if (comp == nullptr) {
2341       ci_env.record_method_not_compilable("no compiler");
2342     } else if (!ci_env.failing()) {
2343       if (WhiteBoxAPI && WhiteBox::compilation_locked) {
2344         whitebox_lock_compilation();
2345       }
2346       comp->compile_method(&ci_env, target, osr_bci, true, directive);
2347 
2348       /* Repeat compilation without installing code for profiling purposes */
2349       int repeat_compilation_count = directive->RepeatCompilationOption;
2350       if (repeat_compilation_count > 0) {
2351         CHeapStringHolder failure_reason;
2352         failure_reason.set(ci_env._failure_reason.get());
2353         while (repeat_compilation_count > 0) {
2354           ResourceMark rm(thread);
2355           task->print_ul("NO CODE INSTALLED");
2356           thread->timeout()->reset();
2357           ci_env._failure_reason.clear();
2358           comp->compile_method(&ci_env, target, osr_bci, false, directive);
2359           repeat_compilation_count--;
2360         }
2361         ci_env._failure_reason.set(failure_reason.get());
2362       }
2363     }
2364 
2365 
2366     if (!ci_env.failing() && !task->is_success()) {
2367       assert(ci_env.failure_reason() != nullptr, "expect failure reason");
2368       assert(false, "compiler should always document failure: %s", ci_env.failure_reason());
2369       // The compiler elected, without comment, not to register a result.
2370       // Do not attempt further compilations of this method.
2371       ci_env.record_method_not_compilable("compile failed");
2372     }
2373 
2374     // Copy this bit to the enclosing block:
2375     compilable = ci_env.compilable();
2376 
2377     if (ci_env.failing()) {
2378       // Duplicate the failure reason string, so that it outlives ciEnv
2379       failure_reason = os::strdup(ci_env.failure_reason(), mtCompiler);
2380       failure_reason_on_C_heap = true;
2381       retry_message = ci_env.retry_message();
2382       ci_env.report_failure(failure_reason);
2383     }
2384 
2385     if (ci_env.failing()) {
2386       handle_compile_error(thread, task, &ci_env, compilable, failure_reason);
2387     }
2388     if (event.should_commit()) {
2389       post_compilation_event(event, task);
2390     }
2391   }
2392 
2393   if (failure_reason != nullptr) {
2394     task->set_failure_reason(failure_reason, failure_reason_on_C_heap);
2395     if (CompilationLog::log() != nullptr) {
2396       CompilationLog::log()->log_failure(thread, task, failure_reason, retry_message);
2397     }
2398     if (PrintCompilation || directive->PrintCompilationOption) {
2399       FormatBufferResource msg = retry_message != nullptr ?
2400         FormatBufferResource("COMPILE SKIPPED: %s (%s)", failure_reason, retry_message) :
2401         FormatBufferResource("COMPILE SKIPPED: %s",      failure_reason);
2402       task->print(tty, msg);
2403     }
2404   }
2405 
2406   DirectivesStack::release(directive);
2407 
2408   methodHandle method(thread, task->method());
2409 
2410   DTRACE_METHOD_COMPILE_END_PROBE(method, compiler_name(task_level), task->is_success());
2411 
2412   collect_statistics(thread, time, task);
2413 
2414   if (PrintCompilation && PrintCompilation2) {
2415     tty->print("%7d ", (int) tty->time_stamp().milliseconds());  // print timestamp
2416     tty->print("%4d ", compile_id);    // print compilation number
2417     tty->print("%s ", (is_osr ? "%" : " "));
2418     if (task->is_success()) {
2419       tty->print("size: %d(%d) ", task->nm_total_size(), task->nm_insts_size());
2420     }
2421     tty->print_cr("time: %d inlined: %d bytes", (int)time.milliseconds(), task->num_inlined_bytecodes());
2422   }
2423 
2424   Log(compilation, codecache) log;
2425   if (log.is_debug()) {
2426     LogStream ls(log.debug());
2427     codecache_print(&ls, /* detailed= */ false);
2428   }
2429   if (PrintCodeCacheOnCompilation) {
2430     codecache_print(/* detailed= */ false);
2431   }
2432   // Disable compilation, if required.
2433   switch (compilable) {
2434   case ciEnv::MethodCompilable_never:
2435     if (is_osr)
2436       method->set_not_osr_compilable_quietly("MethodCompilable_never");
2437     else
2438       method->set_not_compilable_quietly("MethodCompilable_never");
2439     break;
2440   case ciEnv::MethodCompilable_not_at_tier:
2441     if (is_osr)
2442       method->set_not_osr_compilable_quietly("MethodCompilable_not_at_tier", task_level);
2443     else
2444       method->set_not_compilable_quietly("MethodCompilable_not_at_tier", task_level);
2445     break;
2446   }
2447 
2448   // Note that the queued_for_compilation bits are cleared without
2449   // protection of a mutex. [They were set by the requester thread,
2450   // when adding the task to the compile queue -- at which time the
2451   // compile queue lock was held. Subsequently, we acquired the compile
2452   // queue lock to get this task off the compile queue; thus (to belabour
2453   // the point somewhat) our clearing of the bits must be occurring
2454   // only after the setting of the bits. See also 14012000 above.
2455   method->clear_queued_for_compilation();
2456 }
2457 
2458 /**
2459  * The CodeCache is full. Print warning and disable compilation.
2460  * Schedule code cache cleaning so compilation can continue later.
2461  * This function needs to be called only from CodeCache::allocate(),
2462  * since we currently handle a full code cache uniformly.
2463  */
2464 void CompileBroker::handle_full_code_cache(CodeBlobType code_blob_type) {
2465   UseInterpreter = true;
2466   if (UseCompiler || AlwaysCompileLoopMethods ) {
2467     if (xtty != nullptr) {
2468       stringStream s;
2469       // Dump code cache state into a buffer before locking the tty,
2470       // because log_state() will use locks causing lock conflicts.
2471       CodeCache::log_state(&s);
2472       // Lock to prevent tearing
2473       ttyLocker ttyl;
2474       xtty->begin_elem("code_cache_full");
2475       xtty->print("%s", s.freeze());
2476       xtty->stamp();
2477       xtty->end_elem();
2478     }
2479 
2480 #ifndef PRODUCT
2481     if (ExitOnFullCodeCache) {
2482       codecache_print(/* detailed= */ true);
2483       before_exit(JavaThread::current());
2484       exit_globals(); // will delete tty
2485       vm_direct_exit(1);
2486     }
2487 #endif
2488     if (UseCodeCacheFlushing) {
2489       // Since code cache is full, immediately stop new compiles
2490       if (CompileBroker::set_should_compile_new_jobs(CompileBroker::stop_compilation)) {
2491         log_info(codecache)("Code cache is full - disabling compilation");
2492       }
2493     } else {
2494       disable_compilation_forever();
2495     }
2496 
2497     CodeCache::report_codemem_full(code_blob_type, should_print_compiler_warning());
2498   }
2499 }
2500 
2501 // ------------------------------------------------------------------
2502 // CompileBroker::update_compile_perf_data
2503 //
2504 // Record this compilation for debugging purposes.
2505 void CompileBroker::update_compile_perf_data(CompilerThread* thread, const methodHandle& method, bool is_osr) {
2506   ResourceMark rm;
2507   char* method_name = method->name()->as_C_string();
2508   char current_method[CompilerCounters::cmname_buffer_length];
2509   size_t maxLen = CompilerCounters::cmname_buffer_length;
2510 
2511   const char* class_name = method->method_holder()->name()->as_C_string();
2512 
2513   size_t s1len = strlen(class_name);
2514   size_t s2len = strlen(method_name);
2515 
2516   // check if we need to truncate the string
2517   if (s1len + s2len + 2 > maxLen) {
2518 
2519     // the strategy is to lop off the leading characters of the
2520     // class name and the trailing characters of the method name.
2521 
2522     if (s2len + 2 > maxLen) {
2523       // lop of the entire class name string, let snprintf handle
2524       // truncation of the method name.
2525       class_name += s1len; // null string
2526     }
2527     else {
2528       // lop off the extra characters from the front of the class name
2529       class_name += ((s1len + s2len + 2) - maxLen);
2530     }
2531   }
2532 
2533   jio_snprintf(current_method, maxLen, "%s %s", class_name, method_name);
2534 
2535   int last_compile_type = normal_compile;
2536   if (CICountOSR && is_osr) {
2537     last_compile_type = osr_compile;
2538   } else if (CICountNative && method->is_native()) {
2539     last_compile_type = native_compile;
2540   }
2541 
2542   CompilerCounters* counters = thread->counters();
2543   counters->set_current_method(current_method);
2544   counters->set_compile_type((jlong) last_compile_type);
2545 }
2546 
2547 // ------------------------------------------------------------------
2548 // CompileBroker::collect_statistics
2549 //
2550 // Collect statistics about the compilation.
2551 
2552 void CompileBroker::collect_statistics(CompilerThread* thread, elapsedTimer time, CompileTask* task) {
2553   bool success = task->is_success();
2554   methodHandle method (thread, task->method());
2555   int compile_id = task->compile_id();
2556   bool is_osr = (task->osr_bci() != standard_entry_bci);
2557   const int comp_level = task->comp_level();
2558   CompilerCounters* counters = thread->counters();
2559 
2560   MutexLocker locker(CompileStatistics_lock);
2561 
2562   // _perf variables are production performance counters which are
2563   // updated regardless of the setting of the CITime and CITimeEach flags
2564   //
2565 
2566   // account all time, including bailouts and failures in this counter;
2567   // C1 and C2 counters are counting both successful and unsuccessful compiles
2568   _t_total_compilation.add(time);
2569 
2570   // Update compilation times. Used by the implementation of JFR CompilerStatistics
2571   // and java.lang.management.CompilationMXBean.
2572   _perf_total_compilation->inc(time.ticks());
2573   _peak_compilation_time = MAX2(time.milliseconds(), _peak_compilation_time);
2574 
2575   if (!success) {
2576     _total_bailout_count++;
2577     if (UsePerfData) {
2578       _perf_last_failed_method->set_value(counters->current_method());
2579       _perf_last_failed_type->set_value(counters->compile_type());
2580       _perf_total_bailout_count->inc();
2581     }
2582     _t_bailedout_compilation.add(time);
2583   } else if (!task->is_success()) {
2584     if (UsePerfData) {
2585       _perf_last_invalidated_method->set_value(counters->current_method());
2586       _perf_last_invalidated_type->set_value(counters->compile_type());
2587       _perf_total_invalidated_count->inc();
2588     }
2589     _total_invalidated_count++;
2590     _t_invalidated_compilation.add(time);
2591   } else {
2592     // Compilation succeeded
2593     if (CITime) {
2594       int bytes_compiled = method->code_size() + task->num_inlined_bytecodes();
2595       if (is_osr) {
2596         _t_osr_compilation.add(time);
2597         _sum_osr_bytes_compiled += bytes_compiled;
2598       } else {
2599         _t_standard_compilation.add(time);
2600         _sum_standard_bytes_compiled += method->code_size() + task->num_inlined_bytecodes();
2601       }
2602 
2603       // Collect statistic per compilation level
2604       if (comp_level > CompLevel_none && comp_level <= CompLevel_full_optimization) {
2605         CompilerStatistics* stats = &_stats_per_level[comp_level-1];
2606         if (is_osr) {
2607           stats->_osr.update(time, bytes_compiled);
2608         } else {
2609           stats->_standard.update(time, bytes_compiled);
2610         }
2611         stats->_nmethods_size += task->nm_total_size();
2612         stats->_nmethods_code_size += task->nm_insts_size();
2613       } else {
2614         assert(false, "CompilerStatistics object does not exist for compilation level %d", comp_level);
2615       }
2616 
2617       // Collect statistic per compiler
2618       AbstractCompiler* comp = compiler(comp_level);
2619       if (comp) {
2620         CompilerStatistics* stats = comp->stats();
2621         if (is_osr) {
2622           stats->_osr.update(time, bytes_compiled);
2623         } else {
2624           stats->_standard.update(time, bytes_compiled);
2625         }
2626         stats->_nmethods_size += task->nm_total_size();
2627         stats->_nmethods_code_size += task->nm_insts_size();
2628       } else { // if (!comp)
2629         assert(false, "Compiler object must exist");
2630       }
2631     }
2632 
2633     if (UsePerfData) {
2634       // save the name of the last method compiled
2635       _perf_last_method->set_value(counters->current_method());
2636       _perf_last_compile_type->set_value(counters->compile_type());
2637       _perf_last_compile_size->set_value(method->code_size() +
2638                                          task->num_inlined_bytecodes());
2639       if (is_osr) {
2640         _perf_osr_compilation->inc(time.ticks());
2641         _perf_sum_osr_bytes_compiled->inc(method->code_size() + task->num_inlined_bytecodes());
2642       } else {
2643         _perf_standard_compilation->inc(time.ticks());
2644         _perf_sum_standard_bytes_compiled->inc(method->code_size() + task->num_inlined_bytecodes());
2645       }
2646     }
2647 
2648     if (CITimeEach) {
2649       double compile_time = time.seconds();
2650       double bytes_per_sec = compile_time == 0.0 ? 0.0 : (double)(method->code_size() + task->num_inlined_bytecodes()) / compile_time;
2651       tty->print_cr("%3d   seconds: %6.3f bytes/sec : %f (bytes %d + %d inlined)",
2652                     compile_id, compile_time, bytes_per_sec, method->code_size(), task->num_inlined_bytecodes());
2653     }
2654 
2655     // Collect counts of successful compilations
2656     _sum_nmethod_size      += task->nm_total_size();
2657     _sum_nmethod_code_size += task->nm_insts_size();
2658     _largest_nmethod_code_size = MAX2(_largest_nmethod_code_size, (uint) task->nm_insts_size());
2659     _total_compile_count++;
2660 
2661     if (UsePerfData) {
2662       _perf_sum_nmethod_size->inc(     task->nm_total_size());
2663       _perf_sum_nmethod_code_size->inc(task->nm_insts_size());
2664       _perf_total_compile_count->inc();
2665     }
2666 
2667     if (is_osr) {
2668       if (UsePerfData) _perf_total_osr_compile_count->inc();
2669       _total_osr_compile_count++;
2670     } else {
2671       if (UsePerfData) _perf_total_standard_compile_count->inc();
2672       _total_standard_compile_count++;
2673     }
2674   }
2675   // set the current method for the thread to null
2676   if (UsePerfData) counters->set_current_method("");
2677 }
2678 
2679 const char* CompileBroker::compiler_name(int comp_level) {
2680   AbstractCompiler *comp = CompileBroker::compiler(comp_level);
2681   if (comp == nullptr) {
2682     return "no compiler";
2683   } else {
2684     return (comp->name());
2685   }
2686 }
2687 
2688 jlong CompileBroker::total_compilation_ticks() {
2689   return _perf_total_compilation != nullptr ? _perf_total_compilation->get_value() : 0;
2690 }
2691 
2692 void CompileBroker::print_times(const char* name, CompilerStatistics* stats) {
2693   tty->print_cr("  %s {speed: %6.3f bytes/s; standard: %6.3f s, %u bytes, %u methods; osr: %6.3f s, %u bytes, %u methods; nmethods_size: %u bytes; nmethods_code_size: %u bytes}",
2694                 name, stats->bytes_per_second(),
2695                 stats->_standard._time.seconds(), stats->_standard._bytes, stats->_standard._count,
2696                 stats->_osr._time.seconds(), stats->_osr._bytes, stats->_osr._count,
2697                 stats->_nmethods_size, stats->_nmethods_code_size);
2698 }
2699 
2700 void CompileBroker::print_times(bool per_compiler, bool aggregate) {
2701   if (per_compiler) {
2702     if (aggregate) {
2703       tty->cr();
2704       tty->print_cr("Individual compiler times (for compiled methods only)");
2705       tty->print_cr("------------------------------------------------");
2706       tty->cr();
2707     }
2708     for (unsigned int i = 0; i < sizeof(_compilers) / sizeof(AbstractCompiler*); i++) {
2709       AbstractCompiler* comp = _compilers[i];
2710       if (comp != nullptr) {
2711         print_times(comp->name(), comp->stats());
2712       }
2713     }
2714     if (aggregate) {
2715       tty->cr();
2716       tty->print_cr("Individual compilation Tier times (for compiled methods only)");
2717       tty->print_cr("------------------------------------------------");
2718       tty->cr();
2719     }
2720     char tier_name[256];
2721     for (int tier = CompLevel_simple; tier <= CompilationPolicy::highest_compile_level(); tier++) {
2722       CompilerStatistics* stats = &_stats_per_level[tier-1];
2723       os::snprintf_checked(tier_name, sizeof(tier_name), "Tier%d", tier);
2724       print_times(tier_name, stats);
2725     }
2726   }
2727 
2728   if (!aggregate) {
2729     return;
2730   }
2731 
2732   elapsedTimer standard_compilation = CompileBroker::_t_standard_compilation;
2733   elapsedTimer osr_compilation = CompileBroker::_t_osr_compilation;
2734   elapsedTimer total_compilation = CompileBroker::_t_total_compilation;
2735 
2736   uint standard_bytes_compiled = CompileBroker::_sum_standard_bytes_compiled;
2737   uint osr_bytes_compiled = CompileBroker::_sum_osr_bytes_compiled;
2738 
2739   uint standard_compile_count = CompileBroker::_total_standard_compile_count;
2740   uint osr_compile_count = CompileBroker::_total_osr_compile_count;
2741   uint total_compile_count = CompileBroker::_total_compile_count;
2742   uint total_bailout_count = CompileBroker::_total_bailout_count;
2743   uint total_invalidated_count = CompileBroker::_total_invalidated_count;
2744 
2745   uint nmethods_code_size = CompileBroker::_sum_nmethod_code_size;
2746   uint largest_nmethod_code_size = CompileBroker::_largest_nmethod_code_size;
2747   uint nmethods_size = CompileBroker::_sum_nmethod_size;
2748 
2749   tty->cr();
2750   tty->print_cr("Accumulated compiler times");
2751   tty->print_cr("----------------------------------------------------------");
2752                //0000000000111111111122222222223333333333444444444455555555556666666666
2753                //0123456789012345678901234567890123456789012345678901234567890123456789
2754   tty->print_cr("  Total compilation time   : %7.3f s", total_compilation.seconds());
2755   tty->print_cr("    Standard compilation   : %7.3f s, Average : %2.3f s",
2756                 standard_compilation.seconds(),
2757                 standard_compile_count == 0 ? 0.0 : standard_compilation.seconds() / standard_compile_count);
2758   tty->print_cr("    Bailed out compilation : %7.3f s, Average : %2.3f s",
2759                 CompileBroker::_t_bailedout_compilation.seconds(),
2760                 total_bailout_count == 0 ? 0.0 : CompileBroker::_t_bailedout_compilation.seconds() / total_bailout_count);
2761   tty->print_cr("    On stack replacement   : %7.3f s, Average : %2.3f s",
2762                 osr_compilation.seconds(),
2763                 osr_compile_count == 0 ? 0.0 : osr_compilation.seconds() / osr_compile_count);
2764   tty->print_cr("    Invalidated            : %7.3f s, Average : %2.3f s",
2765                 CompileBroker::_t_invalidated_compilation.seconds(),
2766                 total_invalidated_count == 0 ? 0.0 : CompileBroker::_t_invalidated_compilation.seconds() / total_invalidated_count);
2767 
2768   AbstractCompiler *comp = compiler(CompLevel_simple);
2769   if (comp != nullptr) {
2770     tty->cr();
2771     comp->print_timers();
2772   }
2773   comp = compiler(CompLevel_full_optimization);
2774   if (comp != nullptr) {
2775     tty->cr();
2776     comp->print_timers();
2777   }
2778 #if INCLUDE_JVMCI
2779   if (EnableJVMCI) {
2780     JVMCICompiler *jvmci_comp = JVMCICompiler::instance(false, JavaThread::current_or_null());
2781     if (jvmci_comp != nullptr && jvmci_comp != comp) {
2782       tty->cr();
2783       jvmci_comp->print_timers();
2784     }
2785   }
2786 #endif
2787 
2788   tty->cr();
2789   tty->print_cr("  Total compiled methods    : %8u methods", total_compile_count);
2790   tty->print_cr("    Standard compilation    : %8u methods", standard_compile_count);
2791   tty->print_cr("    On stack replacement    : %8u methods", osr_compile_count);
2792   uint tcb = osr_bytes_compiled + standard_bytes_compiled;
2793   tty->print_cr("  Total compiled bytecodes  : %8u bytes", tcb);
2794   tty->print_cr("    Standard compilation    : %8u bytes", standard_bytes_compiled);
2795   tty->print_cr("    On stack replacement    : %8u bytes", osr_bytes_compiled);
2796   double tcs = total_compilation.seconds();
2797   uint bps = tcs == 0.0 ? 0 : (uint)(tcb / tcs);
2798   tty->print_cr("  Average compilation speed : %8u bytes/s", bps);
2799   tty->cr();
2800   tty->print_cr("  largest nmethod code size : %8u bytes", largest_nmethod_code_size);
2801   tty->print_cr("  nmethod code size         : %8u bytes", nmethods_code_size);
2802   tty->print_cr("  nmethod total size        : %8u bytes", nmethods_size);
2803 }
2804 
2805 // Print general/accumulated JIT information.
2806 void CompileBroker::print_info(outputStream *out) {
2807   if (out == nullptr) out = tty;
2808   out->cr();
2809   out->print_cr("======================");
2810   out->print_cr("   General JIT info   ");
2811   out->print_cr("======================");
2812   out->cr();
2813   out->print_cr("            JIT is : %7s",     should_compile_new_jobs() ? "on" : "off");
2814   out->print_cr("  Compiler threads : %7d",     (int)CICompilerCount);
2815   out->cr();
2816   out->print_cr("CodeCache overview");
2817   out->print_cr("--------------------------------------------------------");
2818   out->cr();
2819   out->print_cr("         Reserved size : %7zu KB", CodeCache::max_capacity() / K);
2820   out->print_cr("        Committed size : %7zu KB", CodeCache::capacity() / K);
2821   out->print_cr("  Unallocated capacity : %7zu KB", CodeCache::unallocated_capacity() / K);
2822   out->cr();
2823 }
2824 
2825 // Note: tty_lock must not be held upon entry to this function.
2826 //       Print functions called from herein do "micro-locking" on tty_lock.
2827 //       That's a tradeoff which keeps together important blocks of output.
2828 //       At the same time, continuous tty_lock hold time is kept in check,
2829 //       preventing concurrently printing threads from stalling a long time.
2830 void CompileBroker::print_heapinfo(outputStream* out, const char* function, size_t granularity) {
2831   TimeStamp ts_total;
2832   TimeStamp ts_global;
2833   TimeStamp ts;
2834 
2835   bool allFun = !strcmp(function, "all");
2836   bool aggregate = !strcmp(function, "aggregate") || !strcmp(function, "analyze") || allFun;
2837   bool usedSpace = !strcmp(function, "UsedSpace") || allFun;
2838   bool freeSpace = !strcmp(function, "FreeSpace") || allFun;
2839   bool methodCount = !strcmp(function, "MethodCount") || allFun;
2840   bool methodSpace = !strcmp(function, "MethodSpace") || allFun;
2841   bool methodAge = !strcmp(function, "MethodAge") || allFun;
2842   bool methodNames = !strcmp(function, "MethodNames") || allFun;
2843   bool discard = !strcmp(function, "discard") || allFun;
2844 
2845   if (out == nullptr) {
2846     out = tty;
2847   }
2848 
2849   if (!(aggregate || usedSpace || freeSpace || methodCount || methodSpace || methodAge || methodNames || discard)) {
2850     out->print_cr("\n__ CodeHeapStateAnalytics: Function %s is not supported", function);
2851     out->cr();
2852     return;
2853   }
2854 
2855   ts_total.update(); // record starting point
2856 
2857   if (aggregate) {
2858     print_info(out);
2859   }
2860 
2861   // We hold the CodeHeapStateAnalytics_lock all the time, from here until we leave this function.
2862   // That prevents other threads from destroying (making inconsistent) our view on the CodeHeap.
2863   // When we request individual parts of the analysis via the jcmd interface, it is possible
2864   // that in between another thread (another jcmd user or the vm running into CodeCache OOM)
2865   // updated the aggregated data. We will then see a modified, but again consistent, view
2866   // on the CodeHeap. That's a tolerable tradeoff we have to accept because we can't hold
2867   // a lock across user interaction.
2868 
2869   // We should definitely acquire this lock before acquiring Compile_lock and CodeCache_lock.
2870   // CodeHeapStateAnalytics_lock may be held by a concurrent thread for a long time,
2871   // leading to an unnecessarily long hold time of the other locks we acquired before.
2872   ts.update(); // record starting point
2873   MutexLocker mu0(CodeHeapStateAnalytics_lock, Mutex::_safepoint_check_flag);
2874   out->print_cr("\n__ CodeHeapStateAnalytics lock wait took %10.3f seconds _________\n", ts.seconds());
2875 
2876   // Holding the CodeCache_lock protects from concurrent alterations of the CodeCache.
2877   // Unfortunately, such protection is not sufficient:
2878   // When a new nmethod is created via ciEnv::register_method(), the
2879   // Compile_lock is taken first. After some initializations,
2880   // nmethod::new_nmethod() takes over, grabbing the CodeCache_lock
2881   // immediately (after finalizing the oop references). To lock out concurrent
2882   // modifiers, we have to grab both locks as well in the described sequence.
2883   //
2884   // If we serve an "allFun" call, it is beneficial to hold CodeCache_lock and Compile_lock
2885   // for the entire duration of aggregation and printing. That makes sure we see
2886   // a consistent picture and do not run into issues caused by concurrent alterations.
2887   bool should_take_Compile_lock   = !SafepointSynchronize::is_at_safepoint() &&
2888                                     !Compile_lock->owned_by_self();
2889   bool should_take_CodeCache_lock = !SafepointSynchronize::is_at_safepoint() &&
2890                                     !CodeCache_lock->owned_by_self();
2891   bool take_global_lock_1   =  allFun && should_take_Compile_lock;
2892   bool take_global_lock_2   =  allFun && should_take_CodeCache_lock;
2893   bool take_function_lock_1 = !allFun && should_take_Compile_lock;
2894   bool take_function_lock_2 = !allFun && should_take_CodeCache_lock;
2895   bool take_global_locks    = take_global_lock_1 || take_global_lock_2;
2896   bool take_function_locks  = take_function_lock_1 || take_function_lock_2;
2897 
2898   ts_global.update(); // record starting point
2899 
2900   ConditionalMutexLocker mu1(Compile_lock, take_global_lock_1, Mutex::_safepoint_check_flag);
2901   ConditionalMutexLocker mu2(CodeCache_lock, take_global_lock_2, Mutex::_no_safepoint_check_flag);
2902   if (take_global_locks) {
2903     out->print_cr("\n__ Compile & CodeCache (global) lock wait took %10.3f seconds _________\n", ts_global.seconds());
2904     ts_global.update(); // record starting point
2905   }
2906 
2907   if (aggregate) {
2908     ts.update(); // record starting point
2909     ConditionalMutexLocker mu11(Compile_lock, take_function_lock_1,  Mutex::_safepoint_check_flag);
2910     ConditionalMutexLocker mu22(CodeCache_lock, take_function_lock_2, Mutex::_no_safepoint_check_flag);
2911     if (take_function_locks) {
2912       out->print_cr("\n__ Compile & CodeCache (function) lock wait took %10.3f seconds _________\n", ts.seconds());
2913     }
2914 
2915     ts.update(); // record starting point
2916     CodeCache::aggregate(out, granularity);
2917     if (take_function_locks) {
2918       out->print_cr("\n__ Compile & CodeCache (function) lock hold took %10.3f seconds _________\n", ts.seconds());
2919     }
2920   }
2921 
2922   if (usedSpace) CodeCache::print_usedSpace(out);
2923   if (freeSpace) CodeCache::print_freeSpace(out);
2924   if (methodCount) CodeCache::print_count(out);
2925   if (methodSpace) CodeCache::print_space(out);
2926   if (methodAge) CodeCache::print_age(out);
2927   if (methodNames) {
2928     if (allFun) {
2929       // print_names() can only be used safely if the locks have been continuously held
2930       // since aggregation begin. That is true only for function "all".
2931       CodeCache::print_names(out);
2932     } else {
2933       out->print_cr("\nCodeHeapStateAnalytics: Function 'MethodNames' is only available as part of function 'all'");
2934     }
2935   }
2936   if (discard) CodeCache::discard(out);
2937 
2938   if (take_global_locks) {
2939     out->print_cr("\n__ Compile & CodeCache (global) lock hold took %10.3f seconds _________\n", ts_global.seconds());
2940   }
2941   out->print_cr("\n__ CodeHeapStateAnalytics total duration %10.3f seconds _________\n", ts_total.seconds());
2942 }