1 /*
   2  * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/systemDictionary.hpp"
  27 #include "classfile/vmSymbols.hpp"
  28 #include "code/codeCache.hpp"
  29 #include "compiler/compileBroker.hpp"
  30 #include "compiler/compileLog.hpp"
  31 #include "compiler/compilerOracle.hpp"
  32 #include "interpreter/linkResolver.hpp"
  33 #include "memory/allocation.inline.hpp"
  34 #include "oops/methodData.hpp"
  35 #include "oops/method.hpp"
  36 #include "oops/oop.inline.hpp"
  37 #include "prims/nativeLookup.hpp"
  38 #include "runtime/arguments.hpp"
  39 #include "runtime/atomic.inline.hpp"
  40 #include "runtime/compilationPolicy.hpp"
  41 #include "runtime/init.hpp"
  42 #include "runtime/interfaceSupport.hpp"
  43 #include "runtime/javaCalls.hpp"
  44 #include "runtime/os.hpp"
  45 #include "runtime/sharedRuntime.hpp"
  46 #include "runtime/sweeper.hpp"
  47 #include "trace/tracing.hpp"
  48 #include "utilities/dtrace.hpp"
  49 #include "utilities/events.hpp"
  50 #ifdef COMPILER1
  51 #include "c1/c1_Compiler.hpp"
  52 #endif
  53 #ifdef COMPILER2
  54 #include "opto/c2compiler.hpp"
  55 #endif
  56 #ifdef SHARK
  57 #include "shark/sharkCompiler.hpp"
  58 #endif
  59 
  60 #ifdef DTRACE_ENABLED
  61 
  62 // Only bother with this argument setup if dtrace is available
  63 
  64 #define DTRACE_METHOD_COMPILE_BEGIN_PROBE(method, comp_name)             \
  65   {                                                                      \
  66     Symbol* klass_name = (method)->klass_name();                         \
  67     Symbol* name = (method)->name();                                     \
  68     Symbol* signature = (method)->signature();                           \
  69     HOTSPOT_METHOD_COMPILE_BEGIN(                                        \
  70       (char *) comp_name, strlen(comp_name),                             \
  71       (char *) klass_name->bytes(), klass_name->utf8_length(),           \
  72       (char *) name->bytes(), name->utf8_length(),                       \
  73       (char *) signature->bytes(), signature->utf8_length());            \
  74   }
  75 
  76 #define DTRACE_METHOD_COMPILE_END_PROBE(method, comp_name, success)      \
  77   {                                                                      \
  78     Symbol* klass_name = (method)->klass_name();                         \
  79     Symbol* name = (method)->name();                                     \
  80     Symbol* signature = (method)->signature();                           \
  81     HOTSPOT_METHOD_COMPILE_END(                                          \
  82       (char *) comp_name, strlen(comp_name),                             \
  83       (char *) klass_name->bytes(), klass_name->utf8_length(),           \
  84       (char *) name->bytes(), name->utf8_length(),                       \
  85       (char *) signature->bytes(), signature->utf8_length(), (success)); \
  86   }
  87 
  88 #else //  ndef DTRACE_ENABLED
  89 
  90 #define DTRACE_METHOD_COMPILE_BEGIN_PROBE(method, comp_name)
  91 #define DTRACE_METHOD_COMPILE_END_PROBE(method, comp_name, success)
  92 
  93 #endif // ndef DTRACE_ENABLED
  94 
  95 bool CompileBroker::_initialized = false;
  96 volatile bool CompileBroker::_should_block = false;
  97 volatile jint CompileBroker::_print_compilation_warning = 0;
  98 volatile jint CompileBroker::_should_compile_new_jobs = run_compilation;
  99 
 100 // The installed compiler(s)
 101 AbstractCompiler* CompileBroker::_compilers[2];
 102 
 103 // These counters are used to assign an unique ID to each compilation.
 104 volatile jint CompileBroker::_compilation_id     = 0;
 105 volatile jint CompileBroker::_osr_compilation_id = 0;
 106 
 107 // Debugging information
 108 int  CompileBroker::_last_compile_type     = no_compile;
 109 int  CompileBroker::_last_compile_level    = CompLevel_none;
 110 char CompileBroker::_last_method_compiled[CompileBroker::name_buffer_length];
 111 
 112 // Performance counters
 113 PerfCounter* CompileBroker::_perf_total_compilation = NULL;
 114 PerfCounter* CompileBroker::_perf_osr_compilation = NULL;
 115 PerfCounter* CompileBroker::_perf_standard_compilation = NULL;
 116 
 117 PerfCounter* CompileBroker::_perf_total_bailout_count = NULL;
 118 PerfCounter* CompileBroker::_perf_total_invalidated_count = NULL;
 119 PerfCounter* CompileBroker::_perf_total_compile_count = NULL;
 120 PerfCounter* CompileBroker::_perf_total_osr_compile_count = NULL;
 121 PerfCounter* CompileBroker::_perf_total_standard_compile_count = NULL;
 122 
 123 PerfCounter* CompileBroker::_perf_sum_osr_bytes_compiled = NULL;
 124 PerfCounter* CompileBroker::_perf_sum_standard_bytes_compiled = NULL;
 125 PerfCounter* CompileBroker::_perf_sum_nmethod_size = NULL;
 126 PerfCounter* CompileBroker::_perf_sum_nmethod_code_size = NULL;
 127 
 128 PerfStringVariable* CompileBroker::_perf_last_method = NULL;
 129 PerfStringVariable* CompileBroker::_perf_last_failed_method = NULL;
 130 PerfStringVariable* CompileBroker::_perf_last_invalidated_method = NULL;
 131 PerfVariable*       CompileBroker::_perf_last_compile_type = NULL;
 132 PerfVariable*       CompileBroker::_perf_last_compile_size = NULL;
 133 PerfVariable*       CompileBroker::_perf_last_failed_type = NULL;
 134 PerfVariable*       CompileBroker::_perf_last_invalidated_type = NULL;
 135 
 136 // Timers and counters for generating statistics
 137 elapsedTimer CompileBroker::_t_total_compilation;
 138 elapsedTimer CompileBroker::_t_osr_compilation;
 139 elapsedTimer CompileBroker::_t_standard_compilation;
 140 
 141 int CompileBroker::_total_bailout_count          = 0;
 142 int CompileBroker::_total_invalidated_count      = 0;
 143 int CompileBroker::_total_compile_count          = 0;
 144 int CompileBroker::_total_osr_compile_count      = 0;
 145 int CompileBroker::_total_standard_compile_count = 0;
 146 
 147 int CompileBroker::_sum_osr_bytes_compiled       = 0;
 148 int CompileBroker::_sum_standard_bytes_compiled  = 0;
 149 int CompileBroker::_sum_nmethod_size             = 0;
 150 int CompileBroker::_sum_nmethod_code_size        = 0;
 151 
 152 long CompileBroker::_peak_compilation_time       = 0;
 153 
 154 CompileQueue* CompileBroker::_c2_compile_queue   = NULL;
 155 CompileQueue* CompileBroker::_c1_compile_queue   = NULL;
 156 
 157 GrowableArray<CompilerThread*>* CompileBroker::_compiler_threads = NULL;
 158 
 159 
 160 class CompilationLog : public StringEventLog {
 161  public:
 162   CompilationLog() : StringEventLog("Compilation events") {
 163   }
 164 
 165   void log_compile(JavaThread* thread, CompileTask* task) {
 166     StringLogMessage lm;
 167     stringStream sstr = lm.stream();
 168     // msg.time_stamp().update_to(tty->time_stamp().ticks());
 169     task->print_compilation(&sstr, NULL, true, false);
 170     log(thread, "%s", (const char*)lm);
 171   }
 172 
 173   void log_nmethod(JavaThread* thread, nmethod* nm) {
 174     log(thread, "nmethod %d%s " INTPTR_FORMAT " code ["INTPTR_FORMAT ", " INTPTR_FORMAT "]",
 175         nm->compile_id(), nm->is_osr_method() ? "%" : "",
 176         p2i(nm), p2i(nm->code_begin()), p2i(nm->code_end()));
 177   }
 178 
 179   void log_failure(JavaThread* thread, CompileTask* task, const char* reason, const char* retry_message) {
 180     StringLogMessage lm;
 181     lm.print("%4d   COMPILE SKIPPED: %s", task->compile_id(), reason);
 182     if (retry_message != NULL) {
 183       lm.append(" (%s)", retry_message);
 184     }
 185     lm.print("\n");
 186     log(thread, "%s", (const char*)lm);
 187   }
 188 };
 189 
 190 static CompilationLog* _compilation_log = NULL;
 191 
 192 void compileBroker_init() {
 193   if (LogEvents) {
 194     _compilation_log = new CompilationLog();
 195   }
 196 }
 197 
 198 CompileTaskWrapper::CompileTaskWrapper(CompileTask* task) {
 199   CompilerThread* thread = CompilerThread::current();
 200   thread->set_task(task);
 201   CompileLog*     log  = thread->log();
 202   if (log != NULL)  task->log_task_start(log);
 203 }
 204 
 205 CompileTaskWrapper::~CompileTaskWrapper() {
 206   CompilerThread* thread = CompilerThread::current();
 207   CompileTask* task = thread->task();
 208   CompileLog*  log  = thread->log();
 209   if (log != NULL)  task->log_task_done(log);
 210   thread->set_task(NULL);
 211   task->set_code_handle(NULL);
 212   thread->set_env(NULL);
 213   if (task->is_blocking()) {
 214     MutexLocker notifier(task->lock(), thread);
 215     task->mark_complete();
 216     // Notify the waiting thread that the compilation has completed.
 217     task->lock()->notify_all();
 218   } else {
 219     task->mark_complete();
 220 
 221     // By convention, the compiling thread is responsible for
 222     // recycling a non-blocking CompileTask.
 223     CompileTask::free(task);
 224   }
 225 }
 226 
 227 
 228 CompileTask*  CompileTask::_task_free_list = NULL;
 229 #ifdef ASSERT
 230 int CompileTask::_num_allocated_tasks = 0;
 231 #endif
 232 /**
 233  * Allocate a CompileTask, from the free list if possible.
 234  */
 235 CompileTask* CompileTask::allocate() {
 236   MutexLocker locker(CompileTaskAlloc_lock);
 237   CompileTask* task = NULL;
 238 
 239   if (_task_free_list != NULL) {
 240     task = _task_free_list;
 241     _task_free_list = task->next();
 242     task->set_next(NULL);
 243   } else {
 244     task = new CompileTask();
 245     DEBUG_ONLY(_num_allocated_tasks++;)
 246     assert (_num_allocated_tasks < 10000, "Leaking compilation tasks?");
 247     task->set_next(NULL);
 248     task->set_is_free(true);
 249   }
 250   assert(task->is_free(), "Task must be free.");
 251   task->set_is_free(false);
 252   return task;
 253 }
 254 
 255 
 256 /**
 257  * Add a task to the free list.
 258  */
 259 void CompileTask::free(CompileTask* task) {
 260   MutexLocker locker(CompileTaskAlloc_lock);
 261   if (!task->is_free()) {
 262     task->set_code(NULL);
 263     assert(!task->lock()->is_locked(), "Should not be locked when freed");
 264     JNIHandles::destroy_global(task->_method_holder);
 265     JNIHandles::destroy_global(task->_hot_method_holder);
 266 
 267     task->set_is_free(true);
 268     task->set_next(_task_free_list);
 269     _task_free_list = task;
 270   }
 271 }
 272 
 273 void CompileTask::initialize(int compile_id,
 274                              methodHandle method,
 275                              int osr_bci,
 276                              int comp_level,
 277                              methodHandle hot_method,
 278                              int hot_count,
 279                              const char* comment,
 280                              bool is_blocking) {
 281   assert(!_lock->is_locked(), "bad locking");
 282 
 283   _compile_id = compile_id;
 284   _method = method();
 285   _method_holder = JNIHandles::make_global(method->method_holder()->klass_holder());
 286   _osr_bci = osr_bci;
 287   _is_blocking = is_blocking;
 288   _comp_level = comp_level;
 289   _num_inlined_bytecodes = 0;
 290 
 291   _is_complete = false;
 292   _is_success = false;
 293   _code_handle = NULL;
 294 
 295   _hot_method = NULL;
 296   _hot_method_holder = NULL;
 297   _hot_count = hot_count;
 298   _time_queued = 0;  // tidy
 299   _comment = comment;
 300   _failure_reason = NULL;
 301 
 302   if (LogCompilation) {
 303     _time_queued = os::elapsed_counter();
 304     if (hot_method.not_null()) {
 305       if (hot_method == method) {
 306         _hot_method = _method;
 307       } else {
 308         _hot_method = hot_method();
 309         // only add loader or mirror if different from _method_holder
 310         _hot_method_holder = JNIHandles::make_global(hot_method->method_holder()->klass_holder());
 311       }
 312     }
 313   }
 314 
 315   _next = NULL;
 316 }
 317 
 318 // ------------------------------------------------------------------
 319 // CompileTask::code/set_code
 320 nmethod* CompileTask::code() const {
 321   if (_code_handle == NULL)  return NULL;
 322   return _code_handle->code();
 323 }
 324 void CompileTask::set_code(nmethod* nm) {
 325   if (_code_handle == NULL && nm == NULL)  return;
 326   guarantee(_code_handle != NULL, "");
 327   _code_handle->set_code(nm);
 328   if (nm == NULL)  _code_handle = NULL;  // drop the handle also
 329 }
 330 
 331 void CompileTask::mark_on_stack() {
 332   // Mark these methods as something redefine classes cannot remove.
 333   _method->set_on_stack(true);
 334   if (_hot_method != NULL) {
 335     _hot_method->set_on_stack(true);
 336   }
 337 }
 338 
 339 // ------------------------------------------------------------------
 340 // CompileTask::print_line_on_error
 341 //
 342 // This function is called by fatal error handler when the thread
 343 // causing troubles is a compiler thread.
 344 //
 345 // Do not grab any lock, do not allocate memory.
 346 //
 347 // Otherwise it's the same as CompileTask::print_line()
 348 //
 349 void CompileTask::print_line_on_error(outputStream* st, char* buf, int buflen) {
 350   // print compiler name
 351   st->print("%s:", CompileBroker::compiler_name(comp_level()));
 352   print_compilation(st);
 353 }
 354 
 355 // ------------------------------------------------------------------
 356 // CompileTask::print_line
 357 void CompileTask::print_tty() {
 358   ttyLocker ttyl;  // keep the following output all in one block
 359   // print compiler name if requested
 360   if (CIPrintCompilerName) tty->print("%s:", CompileBroker::compiler_name(comp_level()));
 361     print_compilation(tty);
 362 }
 363 
 364 // ------------------------------------------------------------------
 365 // CompileTask::print_compilation_impl
 366 void CompileTask::print_compilation_impl(outputStream* st, Method* method, int compile_id, int comp_level,
 367                                          bool is_osr_method, int osr_bci, bool is_blocking,
 368                                          const char* msg, bool short_form, bool cr) {
 369   if (!short_form) {
 370     st->print("%7d ", (int) st->time_stamp().milliseconds());  // print timestamp
 371   }
 372   st->print("%4d ", compile_id);    // print compilation number
 373 
 374   // For unloaded methods the transition to zombie occurs after the
 375   // method is cleared so it's impossible to report accurate
 376   // information for that case.
 377   bool is_synchronized = false;
 378   bool has_exception_handler = false;
 379   bool is_native = false;
 380   if (method != NULL) {
 381     is_synchronized       = method->is_synchronized();
 382     has_exception_handler = method->has_exception_handler();
 383     is_native             = method->is_native();
 384   }
 385   // method attributes
 386   const char compile_type   = is_osr_method                   ? '%' : ' ';
 387   const char sync_char      = is_synchronized                 ? 's' : ' ';
 388   const char exception_char = has_exception_handler           ? '!' : ' ';
 389   const char blocking_char  = is_blocking                     ? 'b' : ' ';
 390   const char native_char    = is_native                       ? 'n' : ' ';
 391 
 392   // print method attributes
 393   st->print("%c%c%c%c%c ", compile_type, sync_char, exception_char, blocking_char, native_char);
 394 
 395   if (TieredCompilation) {
 396     if (comp_level != -1)  st->print("%d ", comp_level);
 397     else                   st->print("- ");
 398   }
 399   st->print("     ");  // more indent
 400 
 401   if (method == NULL) {
 402     st->print("(method)");
 403   } else {
 404     method->print_short_name(st);
 405     if (is_osr_method) {
 406       st->print(" @ %d", osr_bci);
 407     }
 408     if (method->is_native())
 409       st->print(" (native)");
 410     else
 411       st->print(" (%d bytes)", method->code_size());
 412   }
 413 
 414   if (msg != NULL) {
 415     st->print("   %s", msg);
 416   }
 417   if (cr) {
 418     st->cr();
 419   }
 420 }
 421 
 422 // ------------------------------------------------------------------
 423 // CompileTask::print_inlining
 424 void CompileTask::print_inlining(outputStream* st, ciMethod* method, int inline_level, int bci, const char* msg) {
 425   //         1234567
 426   st->print("        ");     // print timestamp
 427   //         1234
 428   st->print("     ");        // print compilation number
 429 
 430   // method attributes
 431   if (method->is_loaded()) {
 432     const char sync_char      = method->is_synchronized()        ? 's' : ' ';
 433     const char exception_char = method->has_exception_handlers() ? '!' : ' ';
 434     const char monitors_char  = method->has_monitor_bytecodes()  ? 'm' : ' ';
 435 
 436     // print method attributes
 437     st->print(" %c%c%c  ", sync_char, exception_char, monitors_char);
 438   } else {
 439     //         %s!bn
 440     st->print("      ");     // print method attributes
 441   }
 442 
 443   if (TieredCompilation) {
 444     st->print("  ");
 445   }
 446   st->print("     ");        // more indent
 447   st->print("    ");         // initial inlining indent
 448 
 449   for (int i = 0; i < inline_level; i++)  st->print("  ");
 450 
 451   st->print("@ %d  ", bci);  // print bci
 452   method->print_short_name(st);
 453   if (method->is_loaded())
 454     st->print(" (%d bytes)", method->code_size());
 455   else
 456     st->print(" (not loaded)");
 457 
 458   if (msg != NULL) {
 459     st->print("   %s", msg);
 460   }
 461   st->cr();
 462 }
 463 
 464 // ------------------------------------------------------------------
 465 // CompileTask::print_inline_indent
 466 void CompileTask::print_inline_indent(int inline_level, outputStream* st) {
 467   //         1234567
 468   st->print("        ");     // print timestamp
 469   //         1234
 470   st->print("     ");        // print compilation number
 471   //         %s!bn
 472   st->print("      ");       // print method attributes
 473   if (TieredCompilation) {
 474     st->print("  ");
 475   }
 476   st->print("     ");        // more indent
 477   st->print("    ");         // initial inlining indent
 478   for (int i = 0; i < inline_level; i++)  st->print("  ");
 479 }
 480 
 481 // ------------------------------------------------------------------
 482 // CompileTask::print_compilation
 483 void CompileTask::print_compilation(outputStream* st, const char* msg, bool short_form, bool cr) {
 484   bool is_osr_method = osr_bci() != InvocationEntryBci;
 485   print_compilation_impl(st, method(), compile_id(), comp_level(), is_osr_method, osr_bci(), is_blocking(), msg, short_form, cr);
 486 }
 487 
 488 // ------------------------------------------------------------------
 489 // CompileTask::log_task
 490 void CompileTask::log_task(xmlStream* log) {
 491   Thread* thread = Thread::current();
 492   methodHandle method(thread, this->method());
 493   ResourceMark rm(thread);
 494 
 495   // <task id='9' method='M' osr_bci='X' level='1' blocking='1' stamp='1.234'>
 496   log->print(" compile_id='%d'", _compile_id);
 497   if (_osr_bci != CompileBroker::standard_entry_bci) {
 498     log->print(" compile_kind='osr'");  // same as nmethod::compile_kind
 499   } // else compile_kind='c2c'
 500   if (!method.is_null())  log->method(method);
 501   if (_osr_bci != CompileBroker::standard_entry_bci) {
 502     log->print(" osr_bci='%d'", _osr_bci);
 503   }
 504   if (_comp_level != CompLevel_highest_tier) {
 505     log->print(" level='%d'", _comp_level);
 506   }
 507   if (_is_blocking) {
 508     log->print(" blocking='1'");
 509   }
 510   log->stamp();
 511 }
 512 
 513 
 514 // ------------------------------------------------------------------
 515 // CompileTask::log_task_queued
 516 void CompileTask::log_task_queued() {
 517   Thread* thread = Thread::current();
 518   ttyLocker ttyl;
 519   ResourceMark rm(thread);
 520 
 521   xtty->begin_elem("task_queued");
 522   log_task(xtty);
 523   if (_comment != NULL) {
 524     xtty->print(" comment='%s'", _comment);
 525   }
 526   if (_hot_method != NULL) {
 527     methodHandle hot(thread, _hot_method);
 528     methodHandle method(thread, _method);
 529     if (hot() != method()) {
 530       xtty->method(hot);
 531     }
 532   }
 533   if (_hot_count != 0) {
 534     xtty->print(" hot_count='%d'", _hot_count);
 535   }
 536   xtty->end_elem();
 537 }
 538 
 539 
 540 // ------------------------------------------------------------------
 541 // CompileTask::log_task_start
 542 void CompileTask::log_task_start(CompileLog* log)   {
 543   log->begin_head("task");
 544   log_task(log);
 545   log->end_head();
 546 }
 547 
 548 
 549 // ------------------------------------------------------------------
 550 // CompileTask::log_task_done
 551 void CompileTask::log_task_done(CompileLog* log) {
 552   Thread* thread = Thread::current();
 553   methodHandle method(thread, this->method());
 554   ResourceMark rm(thread);
 555 
 556   if (!_is_success) {
 557     const char* reason = _failure_reason != NULL ? _failure_reason : "unknown";
 558     log->elem("failure reason='%s'", reason);
 559   }
 560 
 561   // <task_done ... stamp='1.234'>  </task>
 562   nmethod* nm = code();
 563   log->begin_elem("task_done success='%d' nmsize='%d' count='%d'",
 564                   _is_success, nm == NULL ? 0 : nm->content_size(),
 565                   method->invocation_count());
 566   int bec = method->backedge_count();
 567   if (bec != 0)  log->print(" backedge_count='%d'", bec);
 568   // Note:  "_is_complete" is about to be set, but is not.
 569   if (_num_inlined_bytecodes != 0) {
 570     log->print(" inlined_bytes='%d'", _num_inlined_bytecodes);
 571   }
 572   log->stamp();
 573   log->end_elem();
 574   log->tail("task");
 575   log->clear_identities();   // next task will have different CI
 576   if (log->unflushed_count() > 2000) {
 577     log->flush();
 578   }
 579   log->mark_file_end();
 580 }
 581 
 582 
 583 
 584 /**
 585  * Add a CompileTask to a CompileQueue.
 586  */
 587 void CompileQueue::add(CompileTask* task) {
 588   assert(lock()->owned_by_self(), "must own lock");
 589 
 590   task->set_next(NULL);
 591   task->set_prev(NULL);
 592 
 593   if (_last == NULL) {
 594     // The compile queue is empty.
 595     assert(_first == NULL, "queue is empty");
 596     _first = task;
 597     _last = task;
 598   } else {
 599     // Append the task to the queue.
 600     assert(_last->next() == NULL, "not last");
 601     _last->set_next(task);
 602     task->set_prev(_last);
 603     _last = task;
 604   }
 605   ++_size;
 606 
 607   // Mark the method as being in the compile queue.
 608   task->method()->set_queued_for_compilation();
 609 
 610   if (CIPrintCompileQueue) {
 611     print_tty();
 612   }
 613 
 614   if (LogCompilation && xtty != NULL) {
 615     task->log_task_queued();
 616   }
 617 
 618   // Notify CompilerThreads that a task is available.
 619   lock()->notify_all();
 620 }
 621 
 622 /**
 623  * Empties compilation queue by putting all compilation tasks onto
 624  * a freelist. Furthermore, the method wakes up all threads that are
 625  * waiting on a compilation task to finish. This can happen if background
 626  * compilation is disabled.
 627  */
 628 void CompileQueue::free_all() {
 629   MutexLocker mu(lock());
 630   CompileTask* next = _first;
 631 
 632   // Iterate over all tasks in the compile queue
 633   while (next != NULL) {
 634     CompileTask* current = next;
 635     next = current->next();
 636     {
 637       // Wake up thread that blocks on the compile task.
 638       MutexLocker ct_lock(current->lock());
 639       current->lock()->notify();
 640     }
 641     // Put the task back on the freelist.
 642     CompileTask::free(current);
 643   }
 644   _first = NULL;
 645 
 646   // Wake up all threads that block on the queue.
 647   lock()->notify_all();
 648 }
 649 
 650 // ------------------------------------------------------------------
 651 // CompileQueue::get
 652 //
 653 // Get the next CompileTask from a CompileQueue
 654 CompileTask* CompileQueue::get() {
 655   NMethodSweeper::possibly_sweep();
 656 
 657   MutexLocker locker(lock());
 658   // If _first is NULL we have no more compile jobs. There are two reasons for
 659   // having no compile jobs: First, we compiled everything we wanted. Second,
 660   // we ran out of code cache so compilation has been disabled. In the latter
 661   // case we perform code cache sweeps to free memory such that we can re-enable
 662   // compilation.
 663   while (_first == NULL) {
 664     // Exit loop if compilation is disabled forever
 665     if (CompileBroker::is_compilation_disabled_forever()) {
 666       return NULL;
 667     }
 668 
 669     if (UseCodeCacheFlushing && !CompileBroker::should_compile_new_jobs()) {
 670       // Wait a certain amount of time to possibly do another sweep.
 671       // We must wait until stack scanning has happened so that we can
 672       // transition a method's state from 'not_entrant' to 'zombie'.
 673       long wait_time = NmethodSweepCheckInterval * 1000;
 674       if (FLAG_IS_DEFAULT(NmethodSweepCheckInterval)) {
 675         // Only one thread at a time can do sweeping. Scale the
 676         // wait time according to the number of compiler threads.
 677         // As a result, the next sweep is likely to happen every 100ms
 678         // with an arbitrary number of threads that do sweeping.
 679         wait_time = 100 * CICompilerCount;
 680       }
 681       bool timeout = lock()->wait(!Mutex::_no_safepoint_check_flag, wait_time);
 682       if (timeout) {
 683         MutexUnlocker ul(lock());
 684         NMethodSweeper::possibly_sweep();
 685       }
 686     } else {
 687       // If there are no compilation tasks and we can compile new jobs
 688       // (i.e., there is enough free space in the code cache) there is
 689       // no need to invoke the sweeper. As a result, the hotness of methods
 690       // remains unchanged. This behavior is desired, since we want to keep
 691       // the stable state, i.e., we do not want to evict methods from the
 692       // code cache if it is unnecessary.
 693       // We need a timed wait here, since compiler threads can exit if compilation
 694       // is disabled forever. We use 5 seconds wait time; the exiting of compiler threads
 695       // is not critical and we do not want idle compiler threads to wake up too often.
 696       lock()->wait(!Mutex::_no_safepoint_check_flag, 5*1000);
 697     }
 698   }
 699 
 700   if (CompileBroker::is_compilation_disabled_forever()) {
 701     return NULL;
 702   }
 703 
 704   CompileTask* task;
 705   {
 706     No_Safepoint_Verifier nsv;
 707     task = CompilationPolicy::policy()->select_task(this);
 708   }
 709   remove(task);
 710   purge_stale_tasks(); // may temporarily release MCQ lock
 711   return task;
 712 }
 713 
 714 // Clean & deallocate stale compile tasks.
 715 // Temporarily releases MethodCompileQueue lock.
 716 void CompileQueue::purge_stale_tasks() {
 717   assert(lock()->owned_by_self(), "must own lock");
 718   if (_first_stale != NULL) {
 719     // Stale tasks are purged when MCQ lock is released,
 720     // but _first_stale updates are protected by MCQ lock.
 721     // Once task processing starts and MCQ lock is released,
 722     // other compiler threads can reuse _first_stale.
 723     CompileTask* head = _first_stale;
 724     _first_stale = NULL;
 725     {
 726       MutexUnlocker ul(lock());
 727       for (CompileTask* task = head; task != NULL; ) {
 728         CompileTask* next_task = task->next();
 729         CompileTaskWrapper ctw(task); // Frees the task
 730         task->set_failure_reason("stale task");
 731         task = next_task;
 732       }
 733     }
 734   }
 735 }
 736 
 737 void CompileQueue::remove(CompileTask* task) {
 738    assert(lock()->owned_by_self(), "must own lock");
 739   if (task->prev() != NULL) {
 740     task->prev()->set_next(task->next());
 741   } else {
 742     // max is the first element
 743     assert(task == _first, "Sanity");
 744     _first = task->next();
 745   }
 746 
 747   if (task->next() != NULL) {
 748     task->next()->set_prev(task->prev());
 749   } else {
 750     // max is the last element
 751     assert(task == _last, "Sanity");
 752     _last = task->prev();
 753   }
 754   --_size;
 755 }
 756 
 757 void CompileQueue::remove_and_mark_stale(CompileTask* task) {
 758   assert(lock()->owned_by_self(), "must own lock");
 759   remove(task);
 760 
 761   // Enqueue the task for reclamation (should be done outside MCQ lock)
 762   task->set_next(_first_stale);
 763   task->set_prev(NULL);
 764   _first_stale = task;
 765 }
 766 
 767 // methods in the compile queue need to be marked as used on the stack
 768 // so that they don't get reclaimed by Redefine Classes
 769 void CompileQueue::mark_on_stack() {
 770   CompileTask* task = _first;
 771   while (task != NULL) {
 772     task->mark_on_stack();
 773     task = task->next();
 774   }
 775 }
 776 
 777 
 778 CompileQueue* CompileBroker::compile_queue(int comp_level) {
 779   if (is_c2_compile(comp_level)) return _c2_compile_queue;
 780   if (is_c1_compile(comp_level)) return _c1_compile_queue;
 781   return NULL;
 782 }
 783 
 784 
 785 void CompileBroker::print_compile_queues(outputStream* st) {
 786   _c1_compile_queue->print(st);
 787   _c2_compile_queue->print(st);
 788 }
 789 
 790 
 791 void CompileQueue::print(outputStream* st) {
 792   assert_locked_or_safepoint(lock());
 793   st->print_cr("Contents of %s", name());
 794   st->print_cr("----------------------------");
 795   CompileTask* task = _first;
 796   if (task == NULL) {
 797     st->print_cr("Empty");;
 798   } else {
 799     while (task != NULL) {
 800       task->print_compilation(st, NULL, true, true);
 801       task = task->next();
 802     }
 803   }
 804   st->print_cr("----------------------------");
 805 }
 806 
 807 void CompileQueue::print_tty() {
 808   ttyLocker ttyl;
 809   print(tty);
 810 }
 811 
 812 CompilerCounters::CompilerCounters(const char* thread_name, int instance, TRAPS) {
 813 
 814   _current_method[0] = '\0';
 815   _compile_type = CompileBroker::no_compile;
 816 
 817   if (UsePerfData) {
 818     ResourceMark rm;
 819 
 820     // create the thread instance name space string - don't create an
 821     // instance subspace if instance is -1 - keeps the adapterThread
 822     // counters  from having a ".0" namespace.
 823     const char* thread_i = (instance == -1) ? thread_name :
 824                       PerfDataManager::name_space(thread_name, instance);
 825 
 826 
 827     char* name = PerfDataManager::counter_name(thread_i, "method");
 828     _perf_current_method =
 829                PerfDataManager::create_string_variable(SUN_CI, name,
 830                                                        cmname_buffer_length,
 831                                                        _current_method, CHECK);
 832 
 833     name = PerfDataManager::counter_name(thread_i, "type");
 834     _perf_compile_type = PerfDataManager::create_variable(SUN_CI, name,
 835                                                           PerfData::U_None,
 836                                                          (jlong)_compile_type,
 837                                                           CHECK);
 838 
 839     name = PerfDataManager::counter_name(thread_i, "time");
 840     _perf_time = PerfDataManager::create_counter(SUN_CI, name,
 841                                                  PerfData::U_Ticks, CHECK);
 842 
 843     name = PerfDataManager::counter_name(thread_i, "compiles");
 844     _perf_compiles = PerfDataManager::create_counter(SUN_CI, name,
 845                                                      PerfData::U_Events, CHECK);
 846   }
 847 }
 848 
 849 // ------------------------------------------------------------------
 850 // CompileBroker::compilation_init
 851 //
 852 // Initialize the Compilation object
 853 void CompileBroker::compilation_init() {
 854   _last_method_compiled[0] = '\0';
 855 
 856   // No need to initialize compilation system if we do not use it.
 857   if (!UseCompiler) {
 858     return;
 859   }
 860 #ifndef SHARK
 861   // Set the interface to the current compiler(s).
 862   int c1_count = CompilationPolicy::policy()->compiler_count(CompLevel_simple);
 863   int c2_count = CompilationPolicy::policy()->compiler_count(CompLevel_full_optimization);
 864 #ifdef COMPILER1
 865   if (c1_count > 0) {
 866     _compilers[0] = new Compiler();
 867   }
 868 #endif // COMPILER1
 869 
 870 #ifdef COMPILER2
 871   if (c2_count > 0) {
 872     _compilers[1] = new C2Compiler();
 873   }
 874 #endif // COMPILER2
 875 
 876 #else // SHARK
 877   int c1_count = 0;
 878   int c2_count = 1;
 879 
 880   _compilers[1] = new SharkCompiler();
 881 #endif // SHARK
 882 
 883   // Start the CompilerThreads
 884   init_compiler_threads(c1_count, c2_count);
 885   // totalTime performance counter is always created as it is required
 886   // by the implementation of java.lang.management.CompilationMBean.
 887   {
 888     EXCEPTION_MARK;
 889     _perf_total_compilation =
 890                  PerfDataManager::create_counter(JAVA_CI, "totalTime",
 891                                                  PerfData::U_Ticks, CHECK);
 892   }
 893 
 894 
 895   if (UsePerfData) {
 896 
 897     EXCEPTION_MARK;
 898 
 899     // create the jvmstat performance counters
 900     _perf_osr_compilation =
 901                  PerfDataManager::create_counter(SUN_CI, "osrTime",
 902                                                  PerfData::U_Ticks, CHECK);
 903 
 904     _perf_standard_compilation =
 905                  PerfDataManager::create_counter(SUN_CI, "standardTime",
 906                                                  PerfData::U_Ticks, CHECK);
 907 
 908     _perf_total_bailout_count =
 909                  PerfDataManager::create_counter(SUN_CI, "totalBailouts",
 910                                                  PerfData::U_Events, CHECK);
 911 
 912     _perf_total_invalidated_count =
 913                  PerfDataManager::create_counter(SUN_CI, "totalInvalidates",
 914                                                  PerfData::U_Events, CHECK);
 915 
 916     _perf_total_compile_count =
 917                  PerfDataManager::create_counter(SUN_CI, "totalCompiles",
 918                                                  PerfData::U_Events, CHECK);
 919     _perf_total_osr_compile_count =
 920                  PerfDataManager::create_counter(SUN_CI, "osrCompiles",
 921                                                  PerfData::U_Events, CHECK);
 922 
 923     _perf_total_standard_compile_count =
 924                  PerfDataManager::create_counter(SUN_CI, "standardCompiles",
 925                                                  PerfData::U_Events, CHECK);
 926 
 927     _perf_sum_osr_bytes_compiled =
 928                  PerfDataManager::create_counter(SUN_CI, "osrBytes",
 929                                                  PerfData::U_Bytes, CHECK);
 930 
 931     _perf_sum_standard_bytes_compiled =
 932                  PerfDataManager::create_counter(SUN_CI, "standardBytes",
 933                                                  PerfData::U_Bytes, CHECK);
 934 
 935     _perf_sum_nmethod_size =
 936                  PerfDataManager::create_counter(SUN_CI, "nmethodSize",
 937                                                  PerfData::U_Bytes, CHECK);
 938 
 939     _perf_sum_nmethod_code_size =
 940                  PerfDataManager::create_counter(SUN_CI, "nmethodCodeSize",
 941                                                  PerfData::U_Bytes, CHECK);
 942 
 943     _perf_last_method =
 944                  PerfDataManager::create_string_variable(SUN_CI, "lastMethod",
 945                                        CompilerCounters::cmname_buffer_length,
 946                                        "", CHECK);
 947 
 948     _perf_last_failed_method =
 949             PerfDataManager::create_string_variable(SUN_CI, "lastFailedMethod",
 950                                        CompilerCounters::cmname_buffer_length,
 951                                        "", CHECK);
 952 
 953     _perf_last_invalidated_method =
 954         PerfDataManager::create_string_variable(SUN_CI, "lastInvalidatedMethod",
 955                                      CompilerCounters::cmname_buffer_length,
 956                                      "", CHECK);
 957 
 958     _perf_last_compile_type =
 959              PerfDataManager::create_variable(SUN_CI, "lastType",
 960                                               PerfData::U_None,
 961                                               (jlong)CompileBroker::no_compile,
 962                                               CHECK);
 963 
 964     _perf_last_compile_size =
 965              PerfDataManager::create_variable(SUN_CI, "lastSize",
 966                                               PerfData::U_Bytes,
 967                                               (jlong)CompileBroker::no_compile,
 968                                               CHECK);
 969 
 970 
 971     _perf_last_failed_type =
 972              PerfDataManager::create_variable(SUN_CI, "lastFailedType",
 973                                               PerfData::U_None,
 974                                               (jlong)CompileBroker::no_compile,
 975                                               CHECK);
 976 
 977     _perf_last_invalidated_type =
 978          PerfDataManager::create_variable(SUN_CI, "lastInvalidatedType",
 979                                           PerfData::U_None,
 980                                           (jlong)CompileBroker::no_compile,
 981                                           CHECK);
 982   }
 983 
 984   _initialized = true;
 985 }
 986 
 987 
 988 CompilerThread* CompileBroker::make_compiler_thread(const char* name, CompileQueue* queue, CompilerCounters* counters,
 989                                                     AbstractCompiler* comp, TRAPS) {
 990   CompilerThread* compiler_thread = NULL;
 991 
 992   Klass* k =
 993     SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(),
 994                                       true, CHECK_0);
 995   instanceKlassHandle klass (THREAD, k);
 996   instanceHandle thread_oop = klass->allocate_instance_handle(CHECK_0);
 997   Handle string = java_lang_String::create_from_str(name, CHECK_0);
 998 
 999   // Initialize thread_oop to put it into the system threadGroup
1000   Handle thread_group (THREAD,  Universe::system_thread_group());
1001   JavaValue result(T_VOID);
1002   JavaCalls::call_special(&result, thread_oop,
1003                        klass,
1004                        vmSymbols::object_initializer_name(),
1005                        vmSymbols::threadgroup_string_void_signature(),
1006                        thread_group,
1007                        string,
1008                        CHECK_0);
1009 
1010   {
1011     MutexLocker mu(Threads_lock, THREAD);
1012     compiler_thread = new CompilerThread(queue, counters);
1013     // At this point the new CompilerThread data-races with this startup
1014     // thread (which I believe is the primoridal thread and NOT the VM
1015     // thread).  This means Java bytecodes being executed at startup can
1016     // queue compile jobs which will run at whatever default priority the
1017     // newly created CompilerThread runs at.
1018 
1019 
1020     // At this point it may be possible that no osthread was created for the
1021     // JavaThread due to lack of memory. We would have to throw an exception
1022     // in that case. However, since this must work and we do not allow
1023     // exceptions anyway, check and abort if this fails.
1024 
1025     if (compiler_thread == NULL || compiler_thread->osthread() == NULL){
1026       vm_exit_during_initialization("java.lang.OutOfMemoryError",
1027                                     os::native_thread_creation_failed_msg());
1028     }
1029 
1030     java_lang_Thread::set_thread(thread_oop(), compiler_thread);
1031 
1032     // Note that this only sets the JavaThread _priority field, which by
1033     // definition is limited to Java priorities and not OS priorities.
1034     // The os-priority is set in the CompilerThread startup code itself
1035 
1036     java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
1037 
1038     // Note that we cannot call os::set_priority because it expects Java
1039     // priorities and we are *explicitly* using OS priorities so that it's
1040     // possible to set the compiler thread priority higher than any Java
1041     // thread.
1042 
1043     int native_prio = CompilerThreadPriority;
1044     if (native_prio == -1) {
1045       if (UseCriticalCompilerThreadPriority) {
1046         native_prio = os::java_to_os_priority[CriticalPriority];
1047       } else {
1048         native_prio = os::java_to_os_priority[NearMaxPriority];
1049       }
1050     }
1051     os::set_native_priority(compiler_thread, native_prio);
1052 
1053     java_lang_Thread::set_daemon(thread_oop());
1054 
1055     compiler_thread->set_threadObj(thread_oop());
1056     compiler_thread->set_compiler(comp);
1057     Threads::add(compiler_thread);
1058     Thread::start(compiler_thread);
1059   }
1060 
1061   // Let go of Threads_lock before yielding
1062   os::naked_yield(); // make sure that the compiler thread is started early (especially helpful on SOLARIS)
1063 
1064   return compiler_thread;
1065 }
1066 
1067 
1068 void CompileBroker::init_compiler_threads(int c1_compiler_count, int c2_compiler_count) {
1069   EXCEPTION_MARK;
1070 #if !defined(ZERO) && !defined(SHARK)
1071   assert(c2_compiler_count > 0 || c1_compiler_count > 0, "No compilers?");
1072 #endif // !ZERO && !SHARK
1073   // Initialize the compilation queue
1074   if (c2_compiler_count > 0) {
1075     _c2_compile_queue  = new CompileQueue("C2 compile queue",  MethodCompileQueue_lock);
1076     _compilers[1]->set_num_compiler_threads(c2_compiler_count);
1077   }
1078   if (c1_compiler_count > 0) {
1079     _c1_compile_queue  = new CompileQueue("C1 compile queue",  MethodCompileQueue_lock);
1080     _compilers[0]->set_num_compiler_threads(c1_compiler_count);
1081   }
1082 
1083   int compiler_count = c1_compiler_count + c2_compiler_count;
1084 
1085   _compiler_threads =
1086     new (ResourceObj::C_HEAP, mtCompiler) GrowableArray<CompilerThread*>(compiler_count, true);
1087 
1088   char name_buffer[256];
1089   for (int i = 0; i < c2_compiler_count; i++) {
1090     // Create a name for our thread.
1091     sprintf(name_buffer, "C2 CompilerThread%d", i);
1092     CompilerCounters* counters = new CompilerCounters("compilerThread", i, CHECK);
1093     // Shark and C2
1094     CompilerThread* new_thread = make_compiler_thread(name_buffer, _c2_compile_queue, counters, _compilers[1], CHECK);
1095     _compiler_threads->append(new_thread);
1096   }
1097 
1098   for (int i = c2_compiler_count; i < compiler_count; i++) {
1099     // Create a name for our thread.
1100     sprintf(name_buffer, "C1 CompilerThread%d", i);
1101     CompilerCounters* counters = new CompilerCounters("compilerThread", i, CHECK);
1102     // C1
1103     CompilerThread* new_thread = make_compiler_thread(name_buffer, _c1_compile_queue, counters, _compilers[0], CHECK);
1104     _compiler_threads->append(new_thread);
1105   }
1106 
1107   if (UsePerfData) {
1108     PerfDataManager::create_constant(SUN_CI, "threads", PerfData::U_Bytes, compiler_count, CHECK);
1109   }
1110 }
1111 
1112 
1113 /**
1114  * Set the methods on the stack as on_stack so that redefine classes doesn't
1115  * reclaim them. This method is executed at a safepoint.
1116  */
1117 void CompileBroker::mark_on_stack() {
1118   assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
1119   // Since we are at a safepoint, we do not need a lock to access
1120   // the compile queues.
1121   if (_c2_compile_queue != NULL) {
1122     _c2_compile_queue->mark_on_stack();
1123   }
1124   if (_c1_compile_queue != NULL) {
1125     _c1_compile_queue->mark_on_stack();
1126   }
1127 }
1128 
1129 // ------------------------------------------------------------------
1130 // CompileBroker::compile_method
1131 //
1132 // Request compilation of a method.
1133 void CompileBroker::compile_method_base(methodHandle method,
1134                                         int osr_bci,
1135                                         int comp_level,
1136                                         methodHandle hot_method,
1137                                         int hot_count,
1138                                         const char* comment,
1139                                         Thread* thread) {
1140   // do nothing if compiler thread(s) is not available
1141   if (!_initialized) {
1142     return;
1143   }
1144 
1145   guarantee(!method->is_abstract(), "cannot compile abstract methods");
1146   assert(method->method_holder()->oop_is_instance(),
1147          "sanity check");
1148   assert(!method->method_holder()->is_not_initialized(),
1149          "method holder must be initialized");
1150   assert(!method->is_method_handle_intrinsic(), "do not enqueue these guys");
1151 
1152   if (CIPrintRequests) {
1153     tty->print("request: ");
1154     method->print_short_name(tty);
1155     if (osr_bci != InvocationEntryBci) {
1156       tty->print(" osr_bci: %d", osr_bci);
1157     }
1158     tty->print(" comment: %s count: %d", comment, hot_count);
1159     if (!hot_method.is_null()) {
1160       tty->print(" hot: ");
1161       if (hot_method() != method()) {
1162           hot_method->print_short_name(tty);
1163       } else {
1164         tty->print("yes");
1165       }
1166     }
1167     tty->cr();
1168   }
1169 
1170   // A request has been made for compilation.  Before we do any
1171   // real work, check to see if the method has been compiled
1172   // in the meantime with a definitive result.
1173   if (compilation_is_complete(method, osr_bci, comp_level)) {
1174     return;
1175   }
1176 
1177 #ifndef PRODUCT
1178   if (osr_bci != -1 && !FLAG_IS_DEFAULT(OSROnlyBCI)) {
1179     if ((OSROnlyBCI > 0) ? (OSROnlyBCI != osr_bci) : (-OSROnlyBCI == osr_bci)) {
1180       // Positive OSROnlyBCI means only compile that bci.  Negative means don't compile that BCI.
1181       return;
1182     }
1183   }
1184 #endif
1185 
1186   // If this method is already in the compile queue, then
1187   // we do not block the current thread.
1188   if (compilation_is_in_queue(method)) {
1189     // We may want to decay our counter a bit here to prevent
1190     // multiple denied requests for compilation.  This is an
1191     // open compilation policy issue. Note: The other possibility,
1192     // in the case that this is a blocking compile request, is to have
1193     // all subsequent blocking requesters wait for completion of
1194     // ongoing compiles. Note that in this case we'll need a protocol
1195     // for freeing the associated compile tasks. [Or we could have
1196     // a single static monitor on which all these waiters sleep.]
1197     return;
1198   }
1199 
1200   // If the requesting thread is holding the pending list lock
1201   // then we just return. We can't risk blocking while holding
1202   // the pending list lock or a 3-way deadlock may occur
1203   // between the reference handler thread, a GC (instigated
1204   // by a compiler thread), and compiled method registration.
1205   if (InstanceRefKlass::owns_pending_list_lock(JavaThread::current())) {
1206     return;
1207   }
1208 
1209   // Outputs from the following MutexLocker block:
1210   CompileTask* task     = NULL;
1211   bool         blocking = false;
1212   CompileQueue* queue  = compile_queue(comp_level);
1213 
1214   // Acquire our lock.
1215   {
1216     MutexLocker locker(queue->lock(), thread);
1217 
1218     // Make sure the method has not slipped into the queues since
1219     // last we checked; note that those checks were "fast bail-outs".
1220     // Here we need to be more careful, see 14012000 below.
1221     if (compilation_is_in_queue(method)) {
1222       return;
1223     }
1224 
1225     // We need to check again to see if the compilation has
1226     // completed.  A previous compilation may have registered
1227     // some result.
1228     if (compilation_is_complete(method, osr_bci, comp_level)) {
1229       return;
1230     }
1231 
1232     // We now know that this compilation is not pending, complete,
1233     // or prohibited.  Assign a compile_id to this compilation
1234     // and check to see if it is in our [Start..Stop) range.
1235     int compile_id = assign_compile_id(method, osr_bci);
1236     if (compile_id == 0) {
1237       // The compilation falls outside the allowed range.
1238       return;
1239     }
1240 
1241     // Should this thread wait for completion of the compile?
1242     blocking = is_compile_blocking();
1243 
1244     // We will enter the compilation in the queue.
1245     // 14012000: Note that this sets the queued_for_compile bits in
1246     // the target method. We can now reason that a method cannot be
1247     // queued for compilation more than once, as follows:
1248     // Before a thread queues a task for compilation, it first acquires
1249     // the compile queue lock, then checks if the method's queued bits
1250     // are set or it has already been compiled. Thus there can not be two
1251     // instances of a compilation task for the same method on the
1252     // compilation queue. Consider now the case where the compilation
1253     // thread has already removed a task for that method from the queue
1254     // and is in the midst of compiling it. In this case, the
1255     // queued_for_compile bits must be set in the method (and these
1256     // will be visible to the current thread, since the bits were set
1257     // under protection of the compile queue lock, which we hold now.
1258     // When the compilation completes, the compiler thread first sets
1259     // the compilation result and then clears the queued_for_compile
1260     // bits. Neither of these actions are protected by a barrier (or done
1261     // under the protection of a lock), so the only guarantee we have
1262     // (on machines with TSO (Total Store Order)) is that these values
1263     // will update in that order. As a result, the only combinations of
1264     // these bits that the current thread will see are, in temporal order:
1265     // <RESULT, QUEUE> :
1266     //     <0, 1> : in compile queue, but not yet compiled
1267     //     <1, 1> : compiled but queue bit not cleared
1268     //     <1, 0> : compiled and queue bit cleared
1269     // Because we first check the queue bits then check the result bits,
1270     // we are assured that we cannot introduce a duplicate task.
1271     // Note that if we did the tests in the reverse order (i.e. check
1272     // result then check queued bit), we could get the result bit before
1273     // the compilation completed, and the queue bit after the compilation
1274     // completed, and end up introducing a "duplicate" (redundant) task.
1275     // In that case, the compiler thread should first check if a method
1276     // has already been compiled before trying to compile it.
1277     // NOTE: in the event that there are multiple compiler threads and
1278     // there is de-optimization/recompilation, things will get hairy,
1279     // and in that case it's best to protect both the testing (here) of
1280     // these bits, and their updating (here and elsewhere) under a
1281     // common lock.
1282     task = create_compile_task(queue,
1283                                compile_id, method,
1284                                osr_bci, comp_level,
1285                                hot_method, hot_count, comment,
1286                                blocking);
1287   }
1288 
1289   if (blocking) {
1290     wait_for_completion(task);
1291   }
1292 }
1293 
1294 
1295 nmethod* CompileBroker::compile_method(methodHandle method, int osr_bci,
1296                                        int comp_level,
1297                                        methodHandle hot_method, int hot_count,
1298                                        const char* comment, Thread* THREAD) {
1299   // make sure arguments make sense
1300   assert(method->method_holder()->oop_is_instance(), "not an instance method");
1301   assert(osr_bci == InvocationEntryBci || (0 <= osr_bci && osr_bci < method->code_size()), "bci out of range");
1302   assert(!method->is_abstract() && (osr_bci == InvocationEntryBci || !method->is_native()), "cannot compile abstract/native methods");
1303   assert(!method->method_holder()->is_not_initialized(), "method holder must be initialized");
1304   // allow any levels for WhiteBox
1305   assert(WhiteBoxAPI || TieredCompilation || comp_level == CompLevel_highest_tier, "only CompLevel_highest_tier must be used in non-tiered");
1306   // return quickly if possible
1307 
1308   // lock, make sure that the compilation
1309   // isn't prohibited in a straightforward way.
1310   AbstractCompiler *comp = CompileBroker::compiler(comp_level);
1311   if (comp == NULL || !comp->can_compile_method(method) ||
1312       compilation_is_prohibited(method, osr_bci, comp_level)) {
1313     return NULL;
1314   }
1315 
1316   if (osr_bci == InvocationEntryBci) {
1317     // standard compilation
1318     nmethod* method_code = method->code();
1319     if (method_code != NULL) {
1320       if (compilation_is_complete(method, osr_bci, comp_level)) {
1321         return method_code;
1322       }
1323     }
1324     if (method->is_not_compilable(comp_level)) {
1325       return NULL;
1326     }
1327   } else {
1328     // osr compilation
1329 #ifndef TIERED
1330     // seems like an assert of dubious value
1331     assert(comp_level == CompLevel_highest_tier,
1332            "all OSR compiles are assumed to be at a single compilation lavel");
1333 #endif // TIERED
1334     // We accept a higher level osr method
1335     nmethod* nm = method->lookup_osr_nmethod_for(osr_bci, comp_level, false);
1336     if (nm != NULL) return nm;
1337     if (method->is_not_osr_compilable(comp_level)) return NULL;
1338   }
1339 
1340   assert(!HAS_PENDING_EXCEPTION, "No exception should be present");
1341   // some prerequisites that are compiler specific
1342   if (comp->is_c2() || comp->is_shark()) {
1343     method->constants()->resolve_string_constants(CHECK_AND_CLEAR_NULL);
1344     // Resolve all classes seen in the signature of the method
1345     // we are compiling.
1346     Method::load_signature_classes(method, CHECK_AND_CLEAR_NULL);
1347   }
1348 
1349   // If the method is native, do the lookup in the thread requesting
1350   // the compilation. Native lookups can load code, which is not
1351   // permitted during compilation.
1352   //
1353   // Note: A native method implies non-osr compilation which is
1354   //       checked with an assertion at the entry of this method.
1355   if (method->is_native() && !method->is_method_handle_intrinsic()) {
1356     bool in_base_library;
1357     address adr = NativeLookup::lookup(method, in_base_library, THREAD);
1358     if (HAS_PENDING_EXCEPTION) {
1359       // In case of an exception looking up the method, we just forget
1360       // about it. The interpreter will kick-in and throw the exception.
1361       method->set_not_compilable(); // implies is_not_osr_compilable()
1362       CLEAR_PENDING_EXCEPTION;
1363       return NULL;
1364     }
1365     assert(method->has_native_function(), "must have native code by now");
1366   }
1367 
1368   // RedefineClasses() has replaced this method; just return
1369   if (method->is_old()) {
1370     return NULL;
1371   }
1372 
1373   // JVMTI -- post_compile_event requires jmethod_id() that may require
1374   // a lock the compiling thread can not acquire. Prefetch it here.
1375   if (JvmtiExport::should_post_compiled_method_load()) {
1376     method->jmethod_id();
1377   }
1378 
1379   // do the compilation
1380   if (method->is_native()) {
1381     if (!PreferInterpreterNativeStubs || method->is_method_handle_intrinsic()) {
1382       // To properly handle the appendix argument for out-of-line calls we are using a small trampoline that
1383       // pops off the appendix argument and jumps to the target (see gen_special_dispatch in SharedRuntime).
1384       //
1385       // Since normal compiled-to-compiled calls are not able to handle such a thing we MUST generate an adapter
1386       // in this case.  If we can't generate one and use it we can not execute the out-of-line method handle calls.
1387       AdapterHandlerLibrary::create_native_wrapper(method);
1388     } else {
1389       return NULL;
1390     }
1391   } else {
1392     // If the compiler is shut off due to code cache getting full
1393     // fail out now so blocking compiles dont hang the java thread
1394     if (!should_compile_new_jobs()) {
1395       CompilationPolicy::policy()->delay_compilation(method());
1396       return NULL;
1397     }
1398     compile_method_base(method, osr_bci, comp_level, hot_method, hot_count, comment, THREAD);
1399   }
1400 
1401   // return requested nmethod
1402   // We accept a higher level osr method
1403   return osr_bci  == InvocationEntryBci ? method->code() : method->lookup_osr_nmethod_for(osr_bci, comp_level, false);
1404 }
1405 
1406 
1407 // ------------------------------------------------------------------
1408 // CompileBroker::compilation_is_complete
1409 //
1410 // See if compilation of this method is already complete.
1411 bool CompileBroker::compilation_is_complete(methodHandle method,
1412                                             int          osr_bci,
1413                                             int          comp_level) {
1414   bool is_osr = (osr_bci != standard_entry_bci);
1415   if (is_osr) {
1416     if (method->is_not_osr_compilable(comp_level)) {
1417       return true;
1418     } else {
1419       nmethod* result = method->lookup_osr_nmethod_for(osr_bci, comp_level, true);
1420       return (result != NULL);
1421     }
1422   } else {
1423     if (method->is_not_compilable(comp_level)) {
1424       return true;
1425     } else {
1426       nmethod* result = method->code();
1427       if (result == NULL) return false;
1428       return comp_level == result->comp_level();
1429     }
1430   }
1431 }
1432 
1433 
1434 /**
1435  * See if this compilation is already requested.
1436  *
1437  * Implementation note: there is only a single "is in queue" bit
1438  * for each method.  This means that the check below is overly
1439  * conservative in the sense that an osr compilation in the queue
1440  * will block a normal compilation from entering the queue (and vice
1441  * versa).  This can be remedied by a full queue search to disambiguate
1442  * cases.  If it is deemed profitable, this may be done.
1443  */
1444 bool CompileBroker::compilation_is_in_queue(methodHandle method) {
1445   return method->queued_for_compilation();
1446 }
1447 
1448 // ------------------------------------------------------------------
1449 // CompileBroker::compilation_is_prohibited
1450 //
1451 // See if this compilation is not allowed.
1452 bool CompileBroker::compilation_is_prohibited(methodHandle method, int osr_bci, int comp_level) {
1453   bool is_native = method->is_native();
1454   // Some compilers may not support the compilation of natives.
1455   AbstractCompiler *comp = compiler(comp_level);
1456   if (is_native &&
1457       (!CICompileNatives || comp == NULL || !comp->supports_native())) {
1458     method->set_not_compilable_quietly(comp_level);
1459     return true;
1460   }
1461 
1462   bool is_osr = (osr_bci != standard_entry_bci);
1463   // Some compilers may not support on stack replacement.
1464   if (is_osr &&
1465       (!CICompileOSR || comp == NULL || !comp->supports_osr())) {
1466     method->set_not_osr_compilable(comp_level);
1467     return true;
1468   }
1469 
1470   // The method may be explicitly excluded by the user.
1471   bool quietly;
1472   if (CompilerOracle::should_exclude(method, quietly)) {
1473     if (!quietly) {
1474       // This does not happen quietly...
1475       ResourceMark rm;
1476       tty->print("### Excluding %s:%s",
1477                  method->is_native() ? "generation of native wrapper" : "compile",
1478                  (method->is_static() ? " static" : ""));
1479       method->print_short_name(tty);
1480       tty->cr();
1481     }
1482     method->set_not_compilable(CompLevel_all, !quietly, "excluded by CompilerOracle");
1483   }
1484 
1485   return false;
1486 }
1487 
1488 /**
1489  * Generate serialized IDs for compilation requests. If certain debugging flags are used
1490  * and the ID is not within the specified range, the method is not compiled and 0 is returned.
1491  * The function also allows to generate separate compilation IDs for OSR compilations.
1492  */
1493 int CompileBroker::assign_compile_id(methodHandle method, int osr_bci) {
1494 #ifdef ASSERT
1495   bool is_osr = (osr_bci != standard_entry_bci);
1496   int id;
1497   if (method->is_native()) {
1498     assert(!is_osr, "can't be osr");
1499     // Adapters, native wrappers and method handle intrinsics
1500     // should be generated always.
1501     return Atomic::add(1, &_compilation_id);
1502   } else if (CICountOSR && is_osr) {
1503     id = Atomic::add(1, &_osr_compilation_id);
1504     if (CIStartOSR <= id && id < CIStopOSR) {
1505       return id;
1506     }
1507   } else {
1508     id = Atomic::add(1, &_compilation_id);
1509     if (CIStart <= id && id < CIStop) {
1510       return id;
1511     }
1512   }
1513 
1514   // Method was not in the appropriate compilation range.
1515   method->set_not_compilable_quietly();
1516   return 0;
1517 #else
1518   // CICountOSR is a develop flag and set to 'false' by default. In a product built,
1519   // only _compilation_id is incremented.
1520   return Atomic::add(1, &_compilation_id);
1521 #endif
1522 }
1523 
1524 /**
1525  * Should the current thread block until this compilation request
1526  * has been fulfilled?
1527  */
1528 bool CompileBroker::is_compile_blocking() {
1529   assert(!InstanceRefKlass::owns_pending_list_lock(JavaThread::current()), "possible deadlock");
1530   return !BackgroundCompilation;
1531 }
1532 
1533 
1534 // ------------------------------------------------------------------
1535 // CompileBroker::preload_classes
1536 void CompileBroker::preload_classes(methodHandle method, TRAPS) {
1537   // Move this code over from c1_Compiler.cpp
1538   ShouldNotReachHere();
1539 }
1540 
1541 
1542 // ------------------------------------------------------------------
1543 // CompileBroker::create_compile_task
1544 //
1545 // Create a CompileTask object representing the current request for
1546 // compilation.  Add this task to the queue.
1547 CompileTask* CompileBroker::create_compile_task(CompileQueue* queue,
1548                                               int           compile_id,
1549                                               methodHandle  method,
1550                                               int           osr_bci,
1551                                               int           comp_level,
1552                                               methodHandle  hot_method,
1553                                               int           hot_count,
1554                                               const char*   comment,
1555                                               bool          blocking) {
1556   CompileTask* new_task = CompileTask::allocate();
1557   new_task->initialize(compile_id, method, osr_bci, comp_level,
1558                        hot_method, hot_count, comment,
1559                        blocking);
1560   queue->add(new_task);
1561   return new_task;
1562 }
1563 
1564 
1565 /**
1566  *  Wait for the compilation task to complete.
1567  */
1568 void CompileBroker::wait_for_completion(CompileTask* task) {
1569   if (CIPrintCompileQueue) {
1570     ttyLocker ttyl;
1571     tty->print_cr("BLOCKING FOR COMPILE");
1572   }
1573 
1574   assert(task->is_blocking(), "can only wait on blocking task");
1575 
1576   JavaThread* thread = JavaThread::current();
1577   thread->set_blocked_on_compilation(true);
1578 
1579   methodHandle method(thread, task->method());
1580   {
1581     MutexLocker waiter(task->lock(), thread);
1582 
1583     while (!task->is_complete() && !is_compilation_disabled_forever()) {
1584       task->lock()->wait();
1585     }
1586   }
1587 
1588   thread->set_blocked_on_compilation(false);
1589   if (is_compilation_disabled_forever()) {
1590     CompileTask::free(task);
1591     return;
1592   }
1593 
1594   // It is harmless to check this status without the lock, because
1595   // completion is a stable property (until the task object is recycled).
1596   assert(task->is_complete(), "Compilation should have completed");
1597   assert(task->code_handle() == NULL, "must be reset");
1598 
1599   // By convention, the waiter is responsible for recycling a
1600   // blocking CompileTask. Since there is only one waiter ever
1601   // waiting on a CompileTask, we know that no one else will
1602   // be using this CompileTask; we can free it.
1603   CompileTask::free(task);
1604 }
1605 
1606 /**
1607  * Initialize compiler thread(s) + compiler object(s). The postcondition
1608  * of this function is that the compiler runtimes are initialized and that
1609  * compiler threads can start compiling.
1610  */
1611 bool CompileBroker::init_compiler_runtime() {
1612   CompilerThread* thread = CompilerThread::current();
1613   AbstractCompiler* comp = thread->compiler();
1614   // Final sanity check - the compiler object must exist
1615   guarantee(comp != NULL, "Compiler object must exist");
1616 
1617   int system_dictionary_modification_counter;
1618   {
1619     MutexLocker locker(Compile_lock, thread);
1620     system_dictionary_modification_counter = SystemDictionary::number_of_modifications();
1621   }
1622 
1623   {
1624     // Must switch to native to allocate ci_env
1625     ThreadToNativeFromVM ttn(thread);
1626     ciEnv ci_env(NULL, system_dictionary_modification_counter);
1627     // Cache Jvmti state
1628     ci_env.cache_jvmti_state();
1629     // Cache DTrace flags
1630     ci_env.cache_dtrace_flags();
1631 
1632     // Switch back to VM state to do compiler initialization
1633     ThreadInVMfromNative tv(thread);
1634     ResetNoHandleMark rnhm;
1635 
1636 
1637     if (!comp->is_shark()) {
1638       // Perform per-thread and global initializations
1639       comp->initialize();
1640     }
1641   }
1642 
1643   if (comp->is_failed()) {
1644     disable_compilation_forever();
1645     // If compiler initialization failed, no compiler thread that is specific to a
1646     // particular compiler runtime will ever start to compile methods.
1647     shutdown_compiler_runtime(comp, thread);
1648     return false;
1649   }
1650 
1651   // C1 specific check
1652   if (comp->is_c1() && (thread->get_buffer_blob() == NULL)) {
1653     warning("Initialization of %s thread failed (no space to run compilers)", thread->name());
1654     return false;
1655   }
1656 
1657   return true;
1658 }
1659 
1660 /**
1661  * If C1 and/or C2 initialization failed, we shut down all compilation.
1662  * We do this to keep things simple. This can be changed if it ever turns
1663  * out to be a problem.
1664  */
1665 void CompileBroker::shutdown_compiler_runtime(AbstractCompiler* comp, CompilerThread* thread) {
1666   // Free buffer blob, if allocated
1667   if (thread->get_buffer_blob() != NULL) {
1668     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1669     CodeCache::free(thread->get_buffer_blob());
1670   }
1671 
1672   if (comp->should_perform_shutdown()) {
1673     // There are two reasons for shutting down the compiler
1674     // 1) compiler runtime initialization failed
1675     // 2) The code cache is full and the following flag is set: -XX:-UseCodeCacheFlushing
1676     warning("%s initialization failed. Shutting down all compilers", comp->name());
1677 
1678     // Only one thread per compiler runtime object enters here
1679     // Set state to shut down
1680     comp->set_shut_down();
1681 
1682     // Delete all queued compilation tasks to make compiler threads exit faster.
1683     if (_c1_compile_queue != NULL) {
1684       _c1_compile_queue->free_all();
1685     }
1686 
1687     if (_c2_compile_queue != NULL) {
1688       _c2_compile_queue->free_all();
1689     }
1690 
1691     // Set flags so that we continue execution with using interpreter only.
1692     UseCompiler    = false;
1693     UseInterpreter = true;
1694 
1695     // We could delete compiler runtimes also. However, there are references to
1696     // the compiler runtime(s) (e.g.,  nmethod::is_compiled_by_c1()) which then
1697     // fail. This can be done later if necessary.
1698   }
1699 }
1700 
1701 // ------------------------------------------------------------------
1702 // CompileBroker::compiler_thread_loop
1703 //
1704 // The main loop run by a CompilerThread.
1705 void CompileBroker::compiler_thread_loop() {
1706   CompilerThread* thread = CompilerThread::current();
1707   CompileQueue* queue = thread->queue();
1708   // For the thread that initializes the ciObjectFactory
1709   // this resource mark holds all the shared objects
1710   ResourceMark rm;
1711 
1712   // First thread to get here will initialize the compiler interface
1713 
1714   if (!ciObjectFactory::is_initialized()) {
1715     ASSERT_IN_VM;
1716     MutexLocker only_one (CompileThread_lock, thread);
1717     if (!ciObjectFactory::is_initialized()) {
1718       ciObjectFactory::initialize();
1719     }
1720   }
1721 
1722   // Open a log.
1723   if (LogCompilation) {
1724     init_compiler_thread_log();
1725   }
1726   CompileLog* log = thread->log();
1727   if (log != NULL) {
1728     log->begin_elem("start_compile_thread name='%s' thread='" UINTX_FORMAT "' process='%d'",
1729                     thread->name(),
1730                     os::current_thread_id(),
1731                     os::current_process_id());
1732     log->stamp();
1733     log->end_elem();
1734   }
1735 
1736   // If compiler thread/runtime initialization fails, exit the compiler thread
1737   if (!init_compiler_runtime()) {
1738     return;
1739   }
1740 
1741   // Poll for new compilation tasks as long as the JVM runs. Compilation
1742   // should only be disabled if something went wrong while initializing the
1743   // compiler runtimes. This, in turn, should not happen. The only known case
1744   // when compiler runtime initialization fails is if there is not enough free
1745   // space in the code cache to generate the necessary stubs, etc.
1746   while (!is_compilation_disabled_forever()) {
1747     // We need this HandleMark to avoid leaking VM handles.
1748     HandleMark hm(thread);
1749 
1750     if (CodeCache::unallocated_capacity() < CodeCacheMinimumFreeSpace) {
1751       // the code cache is really full
1752       handle_full_code_cache();
1753     }
1754 
1755     CompileTask* task = queue->get();
1756     if (task == NULL) {
1757       continue;
1758     }
1759 
1760     // Give compiler threads an extra quanta.  They tend to be bursty and
1761     // this helps the compiler to finish up the job.
1762     if( CompilerThreadHintNoPreempt )
1763       os::hint_no_preempt();
1764 
1765     // trace per thread time and compile statistics
1766     CompilerCounters* counters = ((CompilerThread*)thread)->counters();
1767     PerfTraceTimedEvent(counters->time_counter(), counters->compile_counter());
1768 
1769     // Assign the task to the current thread.  Mark this compilation
1770     // thread as active for the profiler.
1771     CompileTaskWrapper ctw(task);
1772     nmethodLocker result_handle;  // (handle for the nmethod produced by this task)
1773     task->set_code_handle(&result_handle);
1774     methodHandle method(thread, task->method());
1775 
1776     // Never compile a method if breakpoints are present in it
1777     if (method()->number_of_breakpoints() == 0) {
1778       // Compile the method.
1779       if ((UseCompiler || AlwaysCompileLoopMethods) && CompileBroker::should_compile_new_jobs()) {
1780 #ifdef COMPILER1
1781         // Allow repeating compilations for the purpose of benchmarking
1782         // compile speed. This is not useful for customers.
1783         if (CompilationRepeat != 0) {
1784           int compile_count = CompilationRepeat;
1785           while (compile_count > 0) {
1786             invoke_compiler_on_method(task);
1787             nmethod* nm = method->code();
1788             if (nm != NULL) {
1789               nm->make_zombie();
1790               method->clear_code();
1791             }
1792             compile_count--;
1793           }
1794         }
1795 #endif /* COMPILER1 */
1796         invoke_compiler_on_method(task);
1797       } else {
1798         // After compilation is disabled, remove remaining methods from queue
1799         method->clear_queued_for_compilation();
1800         task->set_failure_reason("compilation is disabled");
1801       }
1802     }
1803   }
1804 
1805   // Shut down compiler runtime
1806   shutdown_compiler_runtime(thread->compiler(), thread);
1807 }
1808 
1809 // ------------------------------------------------------------------
1810 // CompileBroker::init_compiler_thread_log
1811 //
1812 // Set up state required by +LogCompilation.
1813 void CompileBroker::init_compiler_thread_log() {
1814     CompilerThread* thread = CompilerThread::current();
1815     char  file_name[4*K];
1816     FILE* fp = NULL;
1817     intx thread_id = os::current_thread_id();
1818     for (int try_temp_dir = 1; try_temp_dir >= 0; try_temp_dir--) {
1819       const char* dir = (try_temp_dir ? os::get_temp_directory() : NULL);
1820       if (dir == NULL) {
1821         jio_snprintf(file_name, sizeof(file_name), "hs_c" UINTX_FORMAT "_pid%u.log",
1822                      thread_id, os::current_process_id());
1823       } else {
1824         jio_snprintf(file_name, sizeof(file_name),
1825                      "%s%shs_c" UINTX_FORMAT "_pid%u.log", dir,
1826                      os::file_separator(), thread_id, os::current_process_id());
1827       }
1828 
1829       fp = fopen(file_name, "at");
1830       if (fp != NULL) {
1831         if (LogCompilation && Verbose) {
1832           tty->print_cr("Opening compilation log %s", file_name);
1833         }
1834         CompileLog* log = new(ResourceObj::C_HEAP, mtCompiler) CompileLog(file_name, fp, thread_id);
1835         thread->init_log(log);
1836 
1837         if (xtty != NULL) {
1838           ttyLocker ttyl;
1839           // Record any per thread log files
1840           xtty->elem("thread_logfile thread='" INTX_FORMAT "' filename='%s'", thread_id, file_name);
1841         }
1842         return;
1843       }
1844     }
1845     warning("Cannot open log file: %s", file_name);
1846 }
1847 
1848 // ------------------------------------------------------------------
1849 // CompileBroker::set_should_block
1850 //
1851 // Set _should_block.
1852 // Call this from the VM, with Threads_lock held and a safepoint requested.
1853 void CompileBroker::set_should_block() {
1854   assert(Threads_lock->owner() == Thread::current(), "must have threads lock");
1855   assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint already");
1856 #ifndef PRODUCT
1857   if (PrintCompilation && (Verbose || WizardMode))
1858     tty->print_cr("notifying compiler thread pool to block");
1859 #endif
1860   _should_block = true;
1861 }
1862 
1863 // ------------------------------------------------------------------
1864 // CompileBroker::maybe_block
1865 //
1866 // Call this from the compiler at convenient points, to poll for _should_block.
1867 void CompileBroker::maybe_block() {
1868   if (_should_block) {
1869 #ifndef PRODUCT
1870     if (PrintCompilation && (Verbose || WizardMode))
1871       tty->print_cr("compiler thread " INTPTR_FORMAT " poll detects block request", p2i(Thread::current()));
1872 #endif
1873     ThreadInVMfromNative tivfn(JavaThread::current());
1874   }
1875 }
1876 
1877 // wrapper for CodeCache::print_summary()
1878 static void codecache_print(bool detailed)
1879 {
1880   ResourceMark rm;
1881   stringStream s;
1882   // Dump code cache  into a buffer before locking the tty,
1883   {
1884     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1885     CodeCache::print_summary(&s, detailed);
1886   }
1887   ttyLocker ttyl;
1888   tty->print("%s", s.as_string());
1889 }
1890 
1891 // ------------------------------------------------------------------
1892 // CompileBroker::invoke_compiler_on_method
1893 //
1894 // Compile a method.
1895 //
1896 void CompileBroker::invoke_compiler_on_method(CompileTask* task) {
1897   if (PrintCompilation) {
1898     ResourceMark rm;
1899     task->print_tty();
1900   }
1901   elapsedTimer time;
1902 
1903   CompilerThread* thread = CompilerThread::current();
1904   ResourceMark rm(thread);
1905 
1906   if (LogEvents) {
1907     _compilation_log->log_compile(thread, task);
1908   }
1909 
1910   // Common flags.
1911   uint compile_id = task->compile_id();
1912   int osr_bci = task->osr_bci();
1913   bool is_osr = (osr_bci != standard_entry_bci);
1914   bool should_log = (thread->log() != NULL);
1915   bool should_break = false;
1916   int task_level = task->comp_level();
1917   {
1918     // create the handle inside it's own block so it can't
1919     // accidentally be referenced once the thread transitions to
1920     // native.  The NoHandleMark before the transition should catch
1921     // any cases where this occurs in the future.
1922     methodHandle method(thread, task->method());
1923     should_break = check_break_at(method, compile_id, is_osr);
1924     if (should_log && !CompilerOracle::should_log(method)) {
1925       should_log = false;
1926     }
1927     assert(!method->is_native(), "no longer compile natives");
1928 
1929     // Save information about this method in case of failure.
1930     set_last_compile(thread, method, is_osr, task_level);
1931 
1932     DTRACE_METHOD_COMPILE_BEGIN_PROBE(method, compiler_name(task_level));
1933   }
1934 
1935   // Allocate a new set of JNI handles.
1936   push_jni_handle_block();
1937   Method* target_handle = task->method();
1938   int compilable = ciEnv::MethodCompilable;
1939   {
1940     int system_dictionary_modification_counter;
1941     {
1942       MutexLocker locker(Compile_lock, thread);
1943       system_dictionary_modification_counter = SystemDictionary::number_of_modifications();
1944     }
1945 
1946     NoHandleMark  nhm;
1947     ThreadToNativeFromVM ttn(thread);
1948 
1949     ciEnv ci_env(task, system_dictionary_modification_counter);
1950     if (should_break) {
1951       ci_env.set_break_at_compile(true);
1952     }
1953     if (should_log) {
1954       ci_env.set_log(thread->log());
1955     }
1956     assert(thread->env() == &ci_env, "set by ci_env");
1957     // The thread-env() field is cleared in ~CompileTaskWrapper.
1958 
1959     // Cache Jvmti state
1960     ci_env.cache_jvmti_state();
1961 
1962     // Cache DTrace flags
1963     ci_env.cache_dtrace_flags();
1964 
1965     ciMethod* target = ci_env.get_method_from_handle(target_handle);
1966 
1967     TraceTime t1("compilation", &time);
1968     EventCompilation event;
1969 
1970     AbstractCompiler *comp = compiler(task_level);
1971     if (comp == NULL) {
1972       ci_env.record_method_not_compilable("no compiler", !TieredCompilation);
1973     } else {
1974       comp->compile_method(&ci_env, target, osr_bci);
1975     }
1976 
1977     if (!ci_env.failing() && task->code() == NULL) {
1978       //assert(false, "compiler should always document failure");
1979       // The compiler elected, without comment, not to register a result.
1980       // Do not attempt further compilations of this method.
1981       ci_env.record_method_not_compilable("compile failed", !TieredCompilation);
1982     }
1983 
1984     // Copy this bit to the enclosing block:
1985     compilable = ci_env.compilable();
1986 
1987     if (ci_env.failing()) {
1988       task->set_failure_reason(ci_env.failure_reason());
1989       const char* retry_message = ci_env.retry_message();
1990       if (_compilation_log != NULL) {
1991         _compilation_log->log_failure(thread, task, ci_env.failure_reason(), retry_message);
1992       }
1993       if (PrintCompilation) {
1994         FormatBufferResource msg = retry_message != NULL ?
1995             err_msg_res("COMPILE SKIPPED: %s (%s)", ci_env.failure_reason(), retry_message) :
1996             err_msg_res("COMPILE SKIPPED: %s",      ci_env.failure_reason());
1997         task->print_compilation(tty, msg);
1998       }
1999     } else {
2000       task->mark_success();
2001       task->set_num_inlined_bytecodes(ci_env.num_inlined_bytecodes());
2002       if (_compilation_log != NULL) {
2003         nmethod* code = task->code();
2004         if (code != NULL) {
2005           _compilation_log->log_nmethod(thread, code);
2006         }
2007       }
2008     }
2009     // simulate crash during compilation
2010     assert(task->compile_id() != CICrashAt, "just as planned");
2011     if (event.should_commit()) {
2012       event.set_method(target->get_Method());
2013       event.set_compileID(compile_id);
2014       event.set_compileLevel(task->comp_level());
2015       event.set_succeded(task->is_success());
2016       event.set_isOsr(is_osr);
2017       event.set_codeSize((task->code() == NULL) ? 0 : task->code()->total_size());
2018       event.set_inlinedBytes(task->num_inlined_bytecodes());
2019       event.commit();
2020     }
2021   }
2022   pop_jni_handle_block();
2023 
2024   methodHandle method(thread, task->method());
2025 
2026   DTRACE_METHOD_COMPILE_END_PROBE(method, compiler_name(task_level), task->is_success());
2027 
2028   collect_statistics(thread, time, task);
2029 
2030   if (PrintCompilation && PrintCompilation2) {
2031     tty->print("%7d ", (int) tty->time_stamp().milliseconds());  // print timestamp
2032     tty->print("%4d ", compile_id);    // print compilation number
2033     tty->print("%s ", (is_osr ? "%" : " "));
2034     if (task->code() != NULL) {
2035       tty->print("size: %d(%d) ", task->code()->total_size(), task->code()->insts_size());
2036     }
2037     tty->print_cr("time: %d inlined: %d bytes", (int)time.milliseconds(), task->num_inlined_bytecodes());
2038   }
2039 
2040   if (PrintCodeCacheOnCompilation)
2041     codecache_print(/* detailed= */ false);
2042 
2043   // Disable compilation, if required.
2044   switch (compilable) {
2045   case ciEnv::MethodCompilable_never:
2046     if (is_osr)
2047       method->set_not_osr_compilable_quietly();
2048     else
2049       method->set_not_compilable_quietly();
2050     break;
2051   case ciEnv::MethodCompilable_not_at_tier:
2052     if (is_osr)
2053       method->set_not_osr_compilable_quietly(task_level);
2054     else
2055       method->set_not_compilable_quietly(task_level);
2056     break;
2057   }
2058 
2059   // Note that the queued_for_compilation bits are cleared without
2060   // protection of a mutex. [They were set by the requester thread,
2061   // when adding the task to the compile queue -- at which time the
2062   // compile queue lock was held. Subsequently, we acquired the compile
2063   // queue lock to get this task off the compile queue; thus (to belabour
2064   // the point somewhat) our clearing of the bits must be occurring
2065   // only after the setting of the bits. See also 14012000 above.
2066   method->clear_queued_for_compilation();
2067 
2068 #ifdef ASSERT
2069   if (CollectedHeap::fired_fake_oom()) {
2070     // The current compile received a fake OOM during compilation so
2071     // go ahead and exit the VM since the test apparently succeeded
2072     tty->print_cr("*** Shutting down VM after successful fake OOM");
2073     vm_exit(0);
2074   }
2075 #endif
2076 }
2077 
2078 /**
2079  * The CodeCache is full.  Print out warning and disable compilation
2080  * or try code cache cleaning so compilation can continue later.
2081  */
2082 void CompileBroker::handle_full_code_cache() {
2083   UseInterpreter = true;
2084   if (UseCompiler || AlwaysCompileLoopMethods ) {
2085     if (xtty != NULL) {
2086       ResourceMark rm;
2087       stringStream s;
2088       // Dump code cache state into a buffer before locking the tty,
2089       // because log_state() will use locks causing lock conflicts.
2090       CodeCache::log_state(&s);
2091       // Lock to prevent tearing
2092       ttyLocker ttyl;
2093       xtty->begin_elem("code_cache_full");
2094       xtty->print("%s", s.as_string());
2095       xtty->stamp();
2096       xtty->end_elem();
2097     }
2098 
2099     CodeCache::report_codemem_full();
2100 
2101 #ifndef PRODUCT
2102     if (CompileTheWorld || ExitOnFullCodeCache) {
2103       codecache_print(/* detailed= */ true);
2104       before_exit(JavaThread::current());
2105       exit_globals(); // will delete tty
2106       vm_direct_exit(CompileTheWorld ? 0 : 1);
2107     }
2108 #endif
2109     if (UseCodeCacheFlushing) {
2110       // Since code cache is full, immediately stop new compiles
2111       if (CompileBroker::set_should_compile_new_jobs(CompileBroker::stop_compilation)) {
2112         NMethodSweeper::log_sweep("disable_compiler");
2113       }
2114       // Switch to 'vm_state'. This ensures that possibly_sweep() can be called
2115       // without having to consider the state in which the current thread is.
2116       ThreadInVMfromUnknown in_vm;
2117       NMethodSweeper::possibly_sweep();
2118     } else {
2119       disable_compilation_forever();
2120     }
2121 
2122     // Print warning only once
2123     if (should_print_compiler_warning()) {
2124       warning("CodeCache is full. Compiler has been disabled.");
2125       warning("Try increasing the code cache size using -XX:ReservedCodeCacheSize=");
2126       codecache_print(/* detailed= */ true);
2127     }
2128   }
2129 }
2130 
2131 // ------------------------------------------------------------------
2132 // CompileBroker::set_last_compile
2133 //
2134 // Record this compilation for debugging purposes.
2135 void CompileBroker::set_last_compile(CompilerThread* thread, methodHandle method, bool is_osr, int comp_level) {
2136   ResourceMark rm;
2137   char* method_name = method->name()->as_C_string();
2138   strncpy(_last_method_compiled, method_name, CompileBroker::name_buffer_length);
2139   _last_method_compiled[CompileBroker::name_buffer_length - 1] = '\0'; // ensure null terminated
2140   char current_method[CompilerCounters::cmname_buffer_length];
2141   size_t maxLen = CompilerCounters::cmname_buffer_length;
2142 
2143   if (UsePerfData) {
2144     const char* class_name = method->method_holder()->name()->as_C_string();
2145 
2146     size_t s1len = strlen(class_name);
2147     size_t s2len = strlen(method_name);
2148 
2149     // check if we need to truncate the string
2150     if (s1len + s2len + 2 > maxLen) {
2151 
2152       // the strategy is to lop off the leading characters of the
2153       // class name and the trailing characters of the method name.
2154 
2155       if (s2len + 2 > maxLen) {
2156         // lop of the entire class name string, let snprintf handle
2157         // truncation of the method name.
2158         class_name += s1len; // null string
2159       }
2160       else {
2161         // lop off the extra characters from the front of the class name
2162         class_name += ((s1len + s2len + 2) - maxLen);
2163       }
2164     }
2165 
2166     jio_snprintf(current_method, maxLen, "%s %s", class_name, method_name);
2167   }
2168 
2169   if (CICountOSR && is_osr) {
2170     _last_compile_type = osr_compile;
2171   } else {
2172     _last_compile_type = normal_compile;
2173   }
2174   _last_compile_level = comp_level;
2175 
2176   if (UsePerfData) {
2177     CompilerCounters* counters = thread->counters();
2178     counters->set_current_method(current_method);
2179     counters->set_compile_type((jlong)_last_compile_type);
2180   }
2181 }
2182 
2183 
2184 // ------------------------------------------------------------------
2185 // CompileBroker::push_jni_handle_block
2186 //
2187 // Push on a new block of JNI handles.
2188 void CompileBroker::push_jni_handle_block() {
2189   JavaThread* thread = JavaThread::current();
2190 
2191   // Allocate a new block for JNI handles.
2192   // Inlined code from jni_PushLocalFrame()
2193   JNIHandleBlock* java_handles = thread->active_handles();
2194   JNIHandleBlock* compile_handles = JNIHandleBlock::allocate_block(thread);
2195   assert(compile_handles != NULL && java_handles != NULL, "should not be NULL");
2196   compile_handles->set_pop_frame_link(java_handles);  // make sure java handles get gc'd.
2197   thread->set_active_handles(compile_handles);
2198 }
2199 
2200 
2201 // ------------------------------------------------------------------
2202 // CompileBroker::pop_jni_handle_block
2203 //
2204 // Pop off the current block of JNI handles.
2205 void CompileBroker::pop_jni_handle_block() {
2206   JavaThread* thread = JavaThread::current();
2207 
2208   // Release our JNI handle block
2209   JNIHandleBlock* compile_handles = thread->active_handles();
2210   JNIHandleBlock* java_handles = compile_handles->pop_frame_link();
2211   thread->set_active_handles(java_handles);
2212   compile_handles->set_pop_frame_link(NULL);
2213   JNIHandleBlock::release_block(compile_handles, thread); // may block
2214 }
2215 
2216 
2217 // ------------------------------------------------------------------
2218 // CompileBroker::check_break_at
2219 //
2220 // Should the compilation break at the current compilation.
2221 bool CompileBroker::check_break_at(methodHandle method, int compile_id, bool is_osr) {
2222   if (CICountOSR && is_osr && (compile_id == CIBreakAtOSR)) {
2223     return true;
2224   } else if( CompilerOracle::should_break_at(method) ) { // break when compiling
2225     return true;
2226   } else {
2227     return (compile_id == CIBreakAt);
2228   }
2229 }
2230 
2231 // ------------------------------------------------------------------
2232 // CompileBroker::collect_statistics
2233 //
2234 // Collect statistics about the compilation.
2235 
2236 void CompileBroker::collect_statistics(CompilerThread* thread, elapsedTimer time, CompileTask* task) {
2237   bool success = task->is_success();
2238   methodHandle method (thread, task->method());
2239   uint compile_id = task->compile_id();
2240   bool is_osr = (task->osr_bci() != standard_entry_bci);
2241   nmethod* code = task->code();
2242   CompilerCounters* counters = thread->counters();
2243 
2244   assert(code == NULL || code->is_locked_by_vm(), "will survive the MutexLocker");
2245   MutexLocker locker(CompileStatistics_lock);
2246 
2247   // _perf variables are production performance counters which are
2248   // updated regardless of the setting of the CITime and CITimeEach flags
2249   //
2250   if (!success) {
2251     _total_bailout_count++;
2252     if (UsePerfData) {
2253       _perf_last_failed_method->set_value(counters->current_method());
2254       _perf_last_failed_type->set_value(counters->compile_type());
2255       _perf_total_bailout_count->inc();
2256     }
2257   } else if (code == NULL) {
2258     if (UsePerfData) {
2259       _perf_last_invalidated_method->set_value(counters->current_method());
2260       _perf_last_invalidated_type->set_value(counters->compile_type());
2261       _perf_total_invalidated_count->inc();
2262     }
2263     _total_invalidated_count++;
2264   } else {
2265     // Compilation succeeded
2266 
2267     // update compilation ticks - used by the implementation of
2268     // java.lang.management.CompilationMBean
2269     _perf_total_compilation->inc(time.ticks());
2270 
2271     _t_total_compilation.add(time);
2272     _peak_compilation_time = time.milliseconds() > _peak_compilation_time ? time.milliseconds() : _peak_compilation_time;
2273 
2274     if (CITime) {
2275       if (is_osr) {
2276         _t_osr_compilation.add(time);
2277         _sum_osr_bytes_compiled += method->code_size() + task->num_inlined_bytecodes();
2278       } else {
2279         _t_standard_compilation.add(time);
2280         _sum_standard_bytes_compiled += method->code_size() + task->num_inlined_bytecodes();
2281       }
2282     }
2283 
2284     if (UsePerfData) {
2285       // save the name of the last method compiled
2286       _perf_last_method->set_value(counters->current_method());
2287       _perf_last_compile_type->set_value(counters->compile_type());
2288       _perf_last_compile_size->set_value(method->code_size() +
2289                                          task->num_inlined_bytecodes());
2290       if (is_osr) {
2291         _perf_osr_compilation->inc(time.ticks());
2292         _perf_sum_osr_bytes_compiled->inc(method->code_size() + task->num_inlined_bytecodes());
2293       } else {
2294         _perf_standard_compilation->inc(time.ticks());
2295         _perf_sum_standard_bytes_compiled->inc(method->code_size() + task->num_inlined_bytecodes());
2296       }
2297     }
2298 
2299     if (CITimeEach) {
2300       float bytes_per_sec = 1.0 * (method->code_size() + task->num_inlined_bytecodes()) / time.seconds();
2301       tty->print_cr("%3d   seconds: %f bytes/sec : %f (bytes %d + %d inlined)",
2302                     compile_id, time.seconds(), bytes_per_sec, method->code_size(), task->num_inlined_bytecodes());
2303     }
2304 
2305     // Collect counts of successful compilations
2306     _sum_nmethod_size      += code->total_size();
2307     _sum_nmethod_code_size += code->insts_size();
2308     _total_compile_count++;
2309 
2310     if (UsePerfData) {
2311       _perf_sum_nmethod_size->inc(     code->total_size());
2312       _perf_sum_nmethod_code_size->inc(code->insts_size());
2313       _perf_total_compile_count->inc();
2314     }
2315 
2316     if (is_osr) {
2317       if (UsePerfData) _perf_total_osr_compile_count->inc();
2318       _total_osr_compile_count++;
2319     } else {
2320       if (UsePerfData) _perf_total_standard_compile_count->inc();
2321       _total_standard_compile_count++;
2322     }
2323   }
2324   // set the current method for the thread to null
2325   if (UsePerfData) counters->set_current_method("");
2326 }
2327 
2328 const char* CompileBroker::compiler_name(int comp_level) {
2329   AbstractCompiler *comp = CompileBroker::compiler(comp_level);
2330   if (comp == NULL) {
2331     return "no compiler";
2332   } else {
2333     return (comp->name());
2334   }
2335 }
2336 
2337 void CompileBroker::print_times() {
2338   tty->cr();
2339   tty->print_cr("Accumulated compiler times (for compiled methods only)");
2340   tty->print_cr("------------------------------------------------");
2341                //0000000000111111111122222222223333333333444444444455555555556666666666
2342                //0123456789012345678901234567890123456789012345678901234567890123456789
2343   tty->print_cr("  Total compilation time   : %6.3f s", CompileBroker::_t_total_compilation.seconds());
2344   tty->print_cr("    Standard compilation   : %6.3f s, Average : %2.3f",
2345                 CompileBroker::_t_standard_compilation.seconds(),
2346                 CompileBroker::_t_standard_compilation.seconds() / CompileBroker::_total_standard_compile_count);
2347   tty->print_cr("    On stack replacement   : %6.3f s, Average : %2.3f", CompileBroker::_t_osr_compilation.seconds(), CompileBroker::_t_osr_compilation.seconds() / CompileBroker::_total_osr_compile_count);
2348 
2349   AbstractCompiler *comp = compiler(CompLevel_simple);
2350   if (comp != NULL) {
2351     comp->print_timers();
2352   }
2353   comp = compiler(CompLevel_full_optimization);
2354   if (comp != NULL) {
2355     comp->print_timers();
2356   }
2357   tty->cr();
2358   tty->print_cr("  Total compiled methods   : %6d methods", CompileBroker::_total_compile_count);
2359   tty->print_cr("    Standard compilation   : %6d methods", CompileBroker::_total_standard_compile_count);
2360   tty->print_cr("    On stack replacement   : %6d methods", CompileBroker::_total_osr_compile_count);
2361   int tcb = CompileBroker::_sum_osr_bytes_compiled + CompileBroker::_sum_standard_bytes_compiled;
2362   tty->print_cr("  Total compiled bytecodes : %6d bytes", tcb);
2363   tty->print_cr("    Standard compilation   : %6d bytes", CompileBroker::_sum_standard_bytes_compiled);
2364   tty->print_cr("    On stack replacement   : %6d bytes", CompileBroker::_sum_osr_bytes_compiled);
2365   int bps = (int)(tcb / CompileBroker::_t_total_compilation.seconds());
2366   tty->print_cr("  Average compilation speed: %6d bytes/s", bps);
2367   tty->cr();
2368   tty->print_cr("  nmethod code size        : %6d bytes", CompileBroker::_sum_nmethod_code_size);
2369   tty->print_cr("  nmethod total size       : %6d bytes", CompileBroker::_sum_nmethod_size);
2370 }
2371 
2372 // Debugging output for failure
2373 void CompileBroker::print_last_compile() {
2374   if ( _last_compile_level != CompLevel_none &&
2375        compiler(_last_compile_level) != NULL &&
2376        _last_method_compiled != NULL &&
2377        _last_compile_type != no_compile) {
2378     if (_last_compile_type == osr_compile) {
2379       tty->print_cr("Last parse:  [osr]%d+++(%d) %s",
2380                     _osr_compilation_id, _last_compile_level, _last_method_compiled);
2381     } else {
2382       tty->print_cr("Last parse:  %d+++(%d) %s",
2383                     _compilation_id, _last_compile_level, _last_method_compiled);
2384     }
2385   }
2386 }
2387 
2388 
2389 void CompileBroker::print_compiler_threads_on(outputStream* st) {
2390 #ifndef PRODUCT
2391   st->print_cr("Compiler thread printing unimplemented.");
2392   st->cr();
2393 #endif
2394 }