1 /* 2 * Copyright (c) 2000, 2018, 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/classLoaderDataGraph.inline.hpp" 27 #include "code/compiledIC.hpp" 28 #include "code/nmethod.hpp" 29 #include "code/scopeDesc.hpp" 30 #include "interpreter/interpreter.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "oops/methodData.hpp" 33 #include "oops/method.inline.hpp" 34 #include "oops/oop.inline.hpp" 35 #include "prims/nativeLookup.hpp" 36 #include "runtime/compilationPolicy.hpp" 37 #include "runtime/frame.hpp" 38 #include "runtime/handles.inline.hpp" 39 #include "runtime/rframe.hpp" 40 #include "runtime/stubRoutines.hpp" 41 #include "runtime/thread.hpp" 42 #include "runtime/tieredThresholdPolicy.hpp" 43 #include "runtime/timer.hpp" 44 #include "runtime/vframe.hpp" 45 #include "runtime/vm_operations.hpp" 46 #include "utilities/events.hpp" 47 #include "utilities/globalDefinitions.hpp" 48 49 #ifdef COMPILER1 50 #include "c1/c1_Compiler.hpp" 51 #endif 52 #ifdef COMPILER2 53 #include "opto/c2compiler.hpp" 54 #endif 55 56 CompilationPolicy* CompilationPolicy::_policy; 57 elapsedTimer CompilationPolicy::_accumulated_time; 58 bool CompilationPolicy::_in_vm_startup; 59 60 // Determine compilation policy based on command line argument 61 void compilationPolicy_init() { 62 CompilationPolicy::set_in_vm_startup(DelayCompilationDuringStartup); 63 64 switch(CompilationPolicyChoice) { 65 case 0: 66 CompilationPolicy::set_policy(new SimpleCompPolicy()); 67 break; 68 69 case 1: 70 #ifdef COMPILER2 71 CompilationPolicy::set_policy(new StackWalkCompPolicy()); 72 #else 73 Unimplemented(); 74 #endif 75 break; 76 case 2: 77 #ifdef TIERED 78 CompilationPolicy::set_policy(new TieredThresholdPolicy()); 79 #else 80 Unimplemented(); 81 #endif 82 break; 83 default: 84 fatal("CompilationPolicyChoice must be in the range: [0-2]"); 85 } 86 CompilationPolicy::policy()->initialize(); 87 } 88 89 void CompilationPolicy::completed_vm_startup() { 90 if (TraceCompilationPolicy) { 91 tty->print("CompilationPolicy: completed vm startup.\n"); 92 } 93 _in_vm_startup = false; 94 } 95 96 // Returns true if m must be compiled before executing it 97 // This is intended to force compiles for methods (usually for 98 // debugging) that would otherwise be interpreted for some reason. 99 bool CompilationPolicy::must_be_compiled(const methodHandle& m, int comp_level) { 100 // Don't allow Xcomp to cause compiles in replay mode 101 if (ReplayCompiles) return false; 102 103 if (m->has_compiled_code()) return false; // already compiled 104 if (!can_be_compiled(m, comp_level)) return false; 105 106 return !UseInterpreter || // must compile all methods 107 (UseCompiler && AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods 108 } 109 110 void CompilationPolicy::compile_if_required(const methodHandle& selected_method, TRAPS) { 111 if (must_be_compiled(selected_method)) { 112 // This path is unusual, mostly used by the '-Xcomp' stress test mode. 113 114 // Note: with several active threads, the must_be_compiled may be true 115 // while can_be_compiled is false; remove assert 116 // assert(CompilationPolicy::can_be_compiled(selected_method), "cannot compile"); 117 if (!THREAD->can_call_java() || THREAD->is_Compiler_thread()) { 118 // don't force compilation, resolve was on behalf of compiler 119 return; 120 } 121 if (selected_method->method_holder()->is_not_initialized()) { 122 // 'is_not_initialized' means not only '!is_initialized', but also that 123 // initialization has not been started yet ('!being_initialized') 124 // Do not force compilation of methods in uninitialized classes. 125 // Note that doing this would throw an assert later, 126 // in CompileBroker::compile_method. 127 // We sometimes use the link resolver to do reflective lookups 128 // even before classes are initialized. 129 return; 130 } 131 CompileBroker::compile_method(selected_method, InvocationEntryBci, 132 CompilationPolicy::policy()->initial_compile_level(), 133 methodHandle(), 0, CompileTask::Reason_MustBeCompiled, CHECK); 134 } 135 } 136 137 // Returns true if m is allowed to be compiled 138 bool CompilationPolicy::can_be_compiled(const methodHandle& m, int comp_level) { 139 // allow any levels for WhiteBox 140 assert(WhiteBoxAPI || comp_level == CompLevel_all || is_compile(comp_level), "illegal compilation level"); 141 142 if (m->is_abstract()) return false; 143 if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false; 144 145 // Math intrinsics should never be compiled as this can lead to 146 // monotonicity problems because the interpreter will prefer the 147 // compiled code to the intrinsic version. This can't happen in 148 // production because the invocation counter can't be incremented 149 // but we shouldn't expose the system to this problem in testing 150 // modes. 151 if (!AbstractInterpreter::can_be_compiled(m)) { 152 return false; 153 } 154 if (comp_level == CompLevel_all) { 155 if (TieredCompilation) { 156 // enough to be compilable at any level for tiered 157 return !m->is_not_compilable(CompLevel_simple) || !m->is_not_compilable(CompLevel_full_optimization); 158 } else { 159 // must be compilable at available level for non-tiered 160 return !m->is_not_compilable(CompLevel_highest_tier); 161 } 162 } else if (is_compile(comp_level)) { 163 return !m->is_not_compilable(comp_level); 164 } 165 return false; 166 } 167 168 // Returns true if m is allowed to be osr compiled 169 bool CompilationPolicy::can_be_osr_compiled(const methodHandle& m, int comp_level) { 170 bool result = false; 171 if (comp_level == CompLevel_all) { 172 if (TieredCompilation) { 173 // enough to be osr compilable at any level for tiered 174 result = !m->is_not_osr_compilable(CompLevel_simple) || !m->is_not_osr_compilable(CompLevel_full_optimization); 175 } else { 176 // must be osr compilable at available level for non-tiered 177 result = !m->is_not_osr_compilable(CompLevel_highest_tier); 178 } 179 } else if (is_compile(comp_level)) { 180 result = !m->is_not_osr_compilable(comp_level); 181 } 182 return (result && can_be_compiled(m, comp_level)); 183 } 184 185 bool CompilationPolicy::is_compilation_enabled() { 186 // NOTE: CompileBroker::should_compile_new_jobs() checks for UseCompiler 187 return !delay_compilation_during_startup() && CompileBroker::should_compile_new_jobs(); 188 } 189 190 CompileTask* CompilationPolicy::select_task_helper(CompileQueue* compile_queue) { 191 #if INCLUDE_JVMCI 192 if (UseJVMCICompiler && !BackgroundCompilation) { 193 /* 194 * In blocking compilation mode, the CompileBroker will make 195 * compilations submitted by a JVMCI compiler thread non-blocking. These 196 * compilations should be scheduled after all blocking compilations 197 * to service non-compiler related compilations sooner and reduce the 198 * chance of such compilations timing out. 199 */ 200 for (CompileTask* task = compile_queue->first(); task != NULL; task = task->next()) { 201 if (task->is_blocking()) { 202 return task; 203 } 204 } 205 } 206 #endif 207 return compile_queue->first(); 208 } 209 210 #ifndef PRODUCT 211 void CompilationPolicy::print_time() { 212 tty->print_cr ("Accumulated compilationPolicy times:"); 213 tty->print_cr ("---------------------------"); 214 tty->print_cr (" Total: %3.3f sec.", _accumulated_time.seconds()); 215 } 216 217 void NonTieredCompPolicy::trace_osr_completion(nmethod* osr_nm) { 218 if (TraceOnStackReplacement) { 219 if (osr_nm == NULL) tty->print_cr("compilation failed"); 220 else tty->print_cr("nmethod " INTPTR_FORMAT, p2i(osr_nm)); 221 } 222 } 223 #endif // !PRODUCT 224 225 void NonTieredCompPolicy::initialize() { 226 // Setup the compiler thread numbers 227 if (CICompilerCountPerCPU) { 228 // Example: if CICompilerCountPerCPU is true, then we get 229 // max(log2(8)-1,1) = 2 compiler threads on an 8-way machine. 230 // May help big-app startup time. 231 _compiler_count = MAX2(log2_int(os::active_processor_count())-1,1); 232 // Make sure there is enough space in the code cache to hold all the compiler buffers 233 size_t buffer_size = 1; 234 #ifdef COMPILER1 235 buffer_size = is_client_compilation_mode_vm() ? Compiler::code_buffer_size() : buffer_size; 236 #endif 237 #ifdef COMPILER2 238 buffer_size = is_server_compilation_mode_vm() ? C2Compiler::initial_code_buffer_size() : buffer_size; 239 #endif 240 int max_count = (ReservedCodeCacheSize - (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3))) / (int)buffer_size; 241 if (_compiler_count > max_count) { 242 // Lower the compiler count such that all buffers fit into the code cache 243 _compiler_count = MAX2(max_count, 1); 244 } 245 FLAG_SET_ERGO(intx, CICompilerCount, _compiler_count); 246 } else { 247 _compiler_count = CICompilerCount; 248 } 249 } 250 251 // Note: this policy is used ONLY if TieredCompilation is off. 252 // compiler_count() behaves the following way: 253 // - with TIERED build (with both COMPILER1 and COMPILER2 defined) it should return 254 // zero for the c1 compilation levels in server compilation mode runs 255 // and c2 compilation levels in client compilation mode runs. 256 // - with COMPILER2 not defined it should return zero for c2 compilation levels. 257 // - with COMPILER1 not defined it should return zero for c1 compilation levels. 258 // - if neither is defined - always return zero. 259 int NonTieredCompPolicy::compiler_count(CompLevel comp_level) { 260 assert(!TieredCompilation, "This policy should not be used with TieredCompilation"); 261 if (COMPILER2_PRESENT(is_server_compilation_mode_vm() && is_c2_compile(comp_level) ||) 262 is_client_compilation_mode_vm() && is_c1_compile(comp_level)) { 263 return _compiler_count; 264 } 265 return 0; 266 } 267 268 void NonTieredCompPolicy::reset_counter_for_invocation_event(const methodHandle& m) { 269 // Make sure invocation and backedge counter doesn't overflow again right away 270 // as would be the case for native methods. 271 272 // BUT also make sure the method doesn't look like it was never executed. 273 // Set carry bit and reduce counter's value to min(count, CompileThreshold/2). 274 MethodCounters* mcs = m->method_counters(); 275 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling"); 276 mcs->invocation_counter()->set_carry(); 277 mcs->backedge_counter()->set_carry(); 278 279 assert(!m->was_never_executed(), "don't reset to 0 -- could be mistaken for never-executed"); 280 } 281 282 void NonTieredCompPolicy::reset_counter_for_back_branch_event(const methodHandle& m) { 283 // Delay next back-branch event but pump up invocation counter to trigger 284 // whole method compilation. 285 MethodCounters* mcs = m->method_counters(); 286 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling"); 287 InvocationCounter* i = mcs->invocation_counter(); 288 InvocationCounter* b = mcs->backedge_counter(); 289 290 // Don't set invocation_counter's value too low otherwise the method will 291 // look like immature (ic < ~5300) which prevents the inlining based on 292 // the type profiling. 293 i->set(i->state(), CompileThreshold); 294 // Don't reset counter too low - it is used to check if OSR method is ready. 295 b->set(b->state(), CompileThreshold / 2); 296 } 297 298 // 299 // CounterDecay 300 // 301 // Iterates through invocation counters and decrements them. This 302 // is done at each safepoint. 303 // 304 class CounterDecay : public AllStatic { 305 static jlong _last_timestamp; 306 static void do_method(Method* m) { 307 MethodCounters* mcs = m->method_counters(); 308 if (mcs != NULL) { 309 mcs->invocation_counter()->decay(); 310 } 311 } 312 public: 313 static void decay(); 314 static bool is_decay_needed() { 315 return (os::javaTimeMillis() - _last_timestamp) > CounterDecayMinIntervalLength; 316 } 317 }; 318 319 jlong CounterDecay::_last_timestamp = 0; 320 321 void CounterDecay::decay() { 322 _last_timestamp = os::javaTimeMillis(); 323 324 // This operation is going to be performed only at the end of a safepoint 325 // and hence GC's will not be going on, all Java mutators are suspended 326 // at this point and hence SystemDictionary_lock is also not needed. 327 assert(SafepointSynchronize::is_at_safepoint(), "can only be executed at a safepoint"); 328 size_t nclasses = ClassLoaderDataGraph::num_instance_classes(); 329 size_t classes_per_tick = nclasses * (CounterDecayMinIntervalLength * 1e-3 / 330 CounterHalfLifeTime); 331 for (size_t i = 0; i < classes_per_tick; i++) { 332 InstanceKlass* k = ClassLoaderDataGraph::try_get_next_class(); 333 if (k != NULL) { 334 k->methods_do(do_method); 335 } 336 } 337 } 338 339 // Called at the end of the safepoint 340 void NonTieredCompPolicy::do_safepoint_work() { 341 if(UseCounterDecay && CounterDecay::is_decay_needed()) { 342 CounterDecay::decay(); 343 } 344 } 345 346 void NonTieredCompPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) { 347 ScopeDesc* sd = trap_scope; 348 MethodCounters* mcs; 349 InvocationCounter* c; 350 for (; !sd->is_top(); sd = sd->sender()) { 351 mcs = sd->method()->method_counters(); 352 if (mcs != NULL) { 353 // Reset ICs of inlined methods, since they can trigger compilations also. 354 mcs->invocation_counter()->reset(); 355 } 356 } 357 mcs = sd->method()->method_counters(); 358 if (mcs != NULL) { 359 c = mcs->invocation_counter(); 360 if (is_osr) { 361 // It was an OSR method, so bump the count higher. 362 c->set(c->state(), CompileThreshold); 363 } else { 364 c->reset(); 365 } 366 mcs->backedge_counter()->reset(); 367 } 368 } 369 370 // This method can be called by any component of the runtime to notify the policy 371 // that it's recommended to delay the compilation of this method. 372 void NonTieredCompPolicy::delay_compilation(Method* method) { 373 MethodCounters* mcs = method->method_counters(); 374 if (mcs != NULL) { 375 mcs->invocation_counter()->decay(); 376 mcs->backedge_counter()->decay(); 377 } 378 } 379 380 void NonTieredCompPolicy::disable_compilation(Method* method) { 381 MethodCounters* mcs = method->method_counters(); 382 if (mcs != NULL) { 383 mcs->invocation_counter()->set_state(InvocationCounter::wait_for_nothing); 384 mcs->backedge_counter()->set_state(InvocationCounter::wait_for_nothing); 385 } 386 } 387 388 CompileTask* NonTieredCompPolicy::select_task(CompileQueue* compile_queue) { 389 return select_task_helper(compile_queue); 390 } 391 392 bool NonTieredCompPolicy::is_mature(Method* method) { 393 MethodData* mdo = method->method_data(); 394 assert(mdo != NULL, "Should be"); 395 uint current = mdo->mileage_of(method); 396 uint initial = mdo->creation_mileage(); 397 if (current < initial) 398 return true; // some sort of overflow 399 uint target; 400 if (ProfileMaturityPercentage <= 0) 401 target = (uint) -ProfileMaturityPercentage; // absolute value 402 else 403 target = (uint)( (ProfileMaturityPercentage * CompileThreshold) / 100 ); 404 return (current >= initial + target); 405 } 406 407 nmethod* NonTieredCompPolicy::event(const methodHandle& method, const methodHandle& inlinee, int branch_bci, 408 int bci, CompLevel comp_level, CompiledMethod* nm, JavaThread* thread) { 409 assert(comp_level == CompLevel_none, "This should be only called from the interpreter"); 410 NOT_PRODUCT(trace_frequency_counter_overflow(method, branch_bci, bci)); 411 if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) { 412 // If certain JVMTI events (e.g. frame pop event) are requested then the 413 // thread is forced to remain in interpreted code. This is 414 // implemented partly by a check in the run_compiled_code 415 // section of the interpreter whether we should skip running 416 // compiled code, and partly by skipping OSR compiles for 417 // interpreted-only threads. 418 if (bci != InvocationEntryBci) { 419 reset_counter_for_back_branch_event(method); 420 return NULL; 421 } 422 } 423 if (CompileTheWorld || ReplayCompiles) { 424 // Don't trigger other compiles in testing mode 425 if (bci == InvocationEntryBci) { 426 reset_counter_for_invocation_event(method); 427 } else { 428 reset_counter_for_back_branch_event(method); 429 } 430 return NULL; 431 } 432 433 if (bci == InvocationEntryBci) { 434 // when code cache is full, compilation gets switched off, UseCompiler 435 // is set to false 436 if (!method->has_compiled_code() && UseCompiler) { 437 method_invocation_event(method, thread); 438 } else { 439 // Force counter overflow on method entry, even if no compilation 440 // happened. (The method_invocation_event call does this also.) 441 reset_counter_for_invocation_event(method); 442 } 443 // compilation at an invocation overflow no longer goes and retries test for 444 // compiled method. We always run the loser of the race as interpreted. 445 // so return NULL 446 return NULL; 447 } else { 448 // counter overflow in a loop => try to do on-stack-replacement 449 nmethod* osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true); 450 NOT_PRODUCT(trace_osr_request(method, osr_nm, bci)); 451 // when code cache is full, we should not compile any more... 452 if (osr_nm == NULL && UseCompiler) { 453 method_back_branch_event(method, bci, thread); 454 osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true); 455 } 456 if (osr_nm == NULL) { 457 reset_counter_for_back_branch_event(method); 458 return NULL; 459 } 460 return osr_nm; 461 } 462 return NULL; 463 } 464 465 #ifndef PRODUCT 466 void NonTieredCompPolicy::trace_frequency_counter_overflow(const methodHandle& m, int branch_bci, int bci) { 467 if (TraceInvocationCounterOverflow) { 468 MethodCounters* mcs = m->method_counters(); 469 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling"); 470 InvocationCounter* ic = mcs->invocation_counter(); 471 InvocationCounter* bc = mcs->backedge_counter(); 472 ResourceMark rm; 473 if (bci == InvocationEntryBci) { 474 tty->print("comp-policy cntr ovfl @ %d in entry of ", bci); 475 } else { 476 tty->print("comp-policy cntr ovfl @ %d in loop of ", bci); 477 } 478 m->print_value(); 479 tty->cr(); 480 ic->print(); 481 bc->print(); 482 if (ProfileInterpreter) { 483 if (bci != InvocationEntryBci) { 484 MethodData* mdo = m->method_data(); 485 if (mdo != NULL) { 486 ProfileData *pd = mdo->bci_to_data(branch_bci); 487 if (pd == NULL) { 488 tty->print_cr("back branch count = N/A (missing ProfileData)"); 489 } else { 490 tty->print_cr("back branch count = %d", pd->as_JumpData()->taken()); 491 } 492 } 493 } 494 } 495 } 496 } 497 498 void NonTieredCompPolicy::trace_osr_request(const methodHandle& method, nmethod* osr, int bci) { 499 if (TraceOnStackReplacement) { 500 ResourceMark rm; 501 tty->print(osr != NULL ? "Reused OSR entry for " : "Requesting OSR entry for "); 502 method->print_short_name(tty); 503 tty->print_cr(" at bci %d", bci); 504 } 505 } 506 #endif // !PRODUCT 507 508 // SimpleCompPolicy - compile current method 509 510 void SimpleCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) { 511 const int comp_level = CompLevel_highest_tier; 512 const int hot_count = m->invocation_count(); 513 reset_counter_for_invocation_event(m); 514 515 if (is_compilation_enabled() && can_be_compiled(m, comp_level)) { 516 CompiledMethod* nm = m->code(); 517 if (nm == NULL ) { 518 CompileBroker::compile_method(m, InvocationEntryBci, comp_level, m, hot_count, CompileTask::Reason_InvocationCount, thread); 519 } 520 } 521 } 522 523 void SimpleCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) { 524 const int comp_level = CompLevel_highest_tier; 525 const int hot_count = m->backedge_count(); 526 527 if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) { 528 CompileBroker::compile_method(m, bci, comp_level, m, hot_count, CompileTask::Reason_BackedgeCount, thread); 529 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));) 530 } 531 } 532 // StackWalkCompPolicy - walk up stack to find a suitable method to compile 533 534 #ifdef COMPILER2 535 const char* StackWalkCompPolicy::_msg = NULL; 536 537 538 // Consider m for compilation 539 void StackWalkCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) { 540 const int comp_level = CompLevel_highest_tier; 541 const int hot_count = m->invocation_count(); 542 reset_counter_for_invocation_event(m); 543 544 if (is_compilation_enabled() && m->code() == NULL && can_be_compiled(m, comp_level)) { 545 ResourceMark rm(thread); 546 frame fr = thread->last_frame(); 547 assert(fr.is_interpreted_frame(), "must be interpreted"); 548 assert(fr.interpreter_frame_method() == m(), "bad method"); 549 550 if (TraceCompilationPolicy) { 551 tty->print("method invocation trigger: "); 552 m->print_short_name(tty); 553 tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", p2i((address)m()), m->code_size()); 554 } 555 RegisterMap reg_map(thread, false); 556 javaVFrame* triggerVF = thread->last_java_vframe(®_map); 557 // triggerVF is the frame that triggered its counter 558 RFrame* first = new InterpretedRFrame(triggerVF->fr(), thread, m()); 559 560 if (first->top_method()->code() != NULL) { 561 // called obsolete method/nmethod -- no need to recompile 562 if (TraceCompilationPolicy) tty->print_cr(" --> " INTPTR_FORMAT, p2i(first->top_method()->code())); 563 } else { 564 if (TimeCompilationPolicy) accumulated_time()->start(); 565 GrowableArray<RFrame*>* stack = new GrowableArray<RFrame*>(50); 566 stack->push(first); 567 RFrame* top = findTopInlinableFrame(stack); 568 if (TimeCompilationPolicy) accumulated_time()->stop(); 569 assert(top != NULL, "findTopInlinableFrame returned null"); 570 if (TraceCompilationPolicy) top->print(); 571 CompileBroker::compile_method(top->top_method(), InvocationEntryBci, comp_level, 572 m, hot_count, CompileTask::Reason_InvocationCount, thread); 573 } 574 } 575 } 576 577 void StackWalkCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) { 578 const int comp_level = CompLevel_highest_tier; 579 const int hot_count = m->backedge_count(); 580 581 if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) { 582 CompileBroker::compile_method(m, bci, comp_level, m, hot_count, CompileTask::Reason_BackedgeCount, thread); 583 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));) 584 } 585 } 586 587 RFrame* StackWalkCompPolicy::findTopInlinableFrame(GrowableArray<RFrame*>* stack) { 588 // go up the stack until finding a frame that (probably) won't be inlined 589 // into its caller 590 RFrame* current = stack->at(0); // current choice for stopping 591 assert( current && !current->is_compiled(), "" ); 592 const char* msg = NULL; 593 594 while (1) { 595 596 // before going up the stack further, check if doing so would get us into 597 // compiled code 598 RFrame* next = senderOf(current, stack); 599 if( !next ) // No next frame up the stack? 600 break; // Then compile with current frame 601 602 Method* m = current->top_method(); 603 Method* next_m = next->top_method(); 604 605 if (TraceCompilationPolicy && Verbose) { 606 tty->print("[caller: "); 607 next_m->print_short_name(tty); 608 tty->print("] "); 609 } 610 611 if( !Inline ) { // Inlining turned off 612 msg = "Inlining turned off"; 613 break; 614 } 615 if (next_m->is_not_compilable()) { // Did fail to compile this before/ 616 msg = "caller not compilable"; 617 break; 618 } 619 if (next->num() > MaxRecompilationSearchLength) { 620 // don't go up too high when searching for recompilees 621 msg = "don't go up any further: > MaxRecompilationSearchLength"; 622 break; 623 } 624 if (next->distance() > MaxInterpretedSearchLength) { 625 // don't go up too high when searching for recompilees 626 msg = "don't go up any further: next > MaxInterpretedSearchLength"; 627 break; 628 } 629 // Compiled frame above already decided not to inline; 630 // do not recompile him. 631 if (next->is_compiled()) { 632 msg = "not going up into optimized code"; 633 break; 634 } 635 636 // Interpreted frame above us was already compiled. Do not force 637 // a recompile, although if the frame above us runs long enough an 638 // OSR might still happen. 639 if( current->is_interpreted() && next_m->has_compiled_code() ) { 640 msg = "not going up -- already compiled caller"; 641 break; 642 } 643 644 // Compute how frequent this call site is. We have current method 'm'. 645 // We know next method 'next_m' is interpreted. Find the call site and 646 // check the various invocation counts. 647 int invcnt = 0; // Caller counts 648 if (ProfileInterpreter) { 649 invcnt = next_m->interpreter_invocation_count(); 650 } 651 int cnt = 0; // Call site counts 652 if (ProfileInterpreter && next_m->method_data() != NULL) { 653 ResourceMark rm; 654 int bci = next->top_vframe()->bci(); 655 ProfileData* data = next_m->method_data()->bci_to_data(bci); 656 if (data != NULL && data->is_CounterData()) 657 cnt = data->as_CounterData()->count(); 658 } 659 660 // Caller counts / call-site counts; i.e. is this call site 661 // a hot call site for method next_m? 662 int freq = (invcnt) ? cnt/invcnt : cnt; 663 664 // Check size and frequency limits 665 if ((msg = shouldInline(m, freq, cnt)) != NULL) { 666 break; 667 } 668 // Check inlining negative tests 669 if ((msg = shouldNotInline(m)) != NULL) { 670 break; 671 } 672 673 674 // If the caller method is too big or something then we do not want to 675 // compile it just to inline a method 676 if (!can_be_compiled(next_m, CompLevel_any)) { 677 msg = "caller cannot be compiled"; 678 break; 679 } 680 681 if( next_m->name() == vmSymbols::class_initializer_name() ) { 682 msg = "do not compile class initializer (OSR ok)"; 683 break; 684 } 685 686 if (TraceCompilationPolicy && Verbose) { 687 tty->print("\n\t check caller: "); 688 next_m->print_short_name(tty); 689 tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", p2i((address)next_m), next_m->code_size()); 690 } 691 692 current = next; 693 } 694 695 assert( !current || !current->is_compiled(), "" ); 696 697 if (TraceCompilationPolicy && msg) tty->print("(%s)\n", msg); 698 699 return current; 700 } 701 702 RFrame* StackWalkCompPolicy::senderOf(RFrame* rf, GrowableArray<RFrame*>* stack) { 703 RFrame* sender = rf->caller(); 704 if (sender && sender->num() == stack->length()) stack->push(sender); 705 return sender; 706 } 707 708 709 const char* StackWalkCompPolicy::shouldInline(const methodHandle& m, float freq, int cnt) { 710 // Allows targeted inlining 711 // positive filter: should send be inlined? returns NULL (--> yes) 712 // or rejection msg 713 int max_size = MaxInlineSize; 714 int cost = m->code_size(); 715 716 // Check for too many throws (and not too huge) 717 if (m->interpreter_throwout_count() > InlineThrowCount && cost < InlineThrowMaxSize ) { 718 return NULL; 719 } 720 721 // bump the max size if the call is frequent 722 if ((freq >= InlineFrequencyRatio) || (cnt >= InlineFrequencyCount)) { 723 if (TraceFrequencyInlining) { 724 tty->print("(Inlined frequent method)\n"); 725 m->print(); 726 } 727 max_size = FreqInlineSize; 728 } 729 if (cost > max_size) { 730 return (_msg = "too big"); 731 } 732 return NULL; 733 } 734 735 736 const char* StackWalkCompPolicy::shouldNotInline(const methodHandle& m) { 737 // negative filter: should send NOT be inlined? returns NULL (--> inline) or rejection msg 738 if (m->is_abstract()) return (_msg = "abstract method"); 739 // note: we allow ik->is_abstract() 740 if (!m->method_holder()->is_initialized()) return (_msg = "method holder not initialized"); 741 if (m->is_native()) return (_msg = "native method"); 742 CompiledMethod* m_code = m->code(); 743 if (m_code != NULL && m_code->code_size() > InlineSmallCode) 744 return (_msg = "already compiled into a big method"); 745 746 // use frequency-based objections only for non-trivial methods 747 if (m->code_size() <= MaxTrivialSize) return NULL; 748 if (UseInterpreter) { // don't use counts with -Xcomp 749 if ((m->code() == NULL) && m->was_never_executed()) return (_msg = "never executed"); 750 if (!m->was_executed_more_than(MIN2(MinInliningThreshold, CompileThreshold >> 1))) return (_msg = "executed < MinInliningThreshold times"); 751 } 752 if (Method::has_unloaded_classes_in_signature(m, JavaThread::current())) return (_msg = "unloaded signature classes"); 753 754 return NULL; 755 } 756 757 758 759 #endif // COMPILER2