1 /* 2 * Copyright (c) 1997, 2025, 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 "classfile/javaClasses.inline.hpp" 26 #include "classfile/symbolTable.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "classfile/vmClasses.hpp" 29 #include "code/codeCache.hpp" 30 #include "code/debugInfoRec.hpp" 31 #include "code/nmethod.hpp" 32 #include "code/pcDesc.hpp" 33 #include "code/scopeDesc.hpp" 34 #include "compiler/compilationPolicy.hpp" 35 #include "compiler/compilerDefinitions.inline.hpp" 36 #include "gc/shared/collectedHeap.hpp" 37 #include "gc/shared/memAllocator.hpp" 38 #include "interpreter/bytecode.inline.hpp" 39 #include "interpreter/bytecodeStream.hpp" 40 #include "interpreter/interpreter.hpp" 41 #include "interpreter/oopMapCache.hpp" 42 #include "jvm.h" 43 #include "logging/log.hpp" 44 #include "logging/logLevel.hpp" 45 #include "logging/logMessage.hpp" 46 #include "logging/logStream.hpp" 47 #include "memory/allocation.inline.hpp" 48 #include "memory/oopFactory.hpp" 49 #include "memory/resourceArea.hpp" 50 #include "memory/universe.hpp" 51 #include "oops/constantPool.hpp" 52 #include "oops/fieldStreams.inline.hpp" 53 #include "oops/method.hpp" 54 #include "oops/objArrayKlass.hpp" 55 #include "oops/objArrayOop.inline.hpp" 56 #include "oops/oop.inline.hpp" 57 #include "oops/typeArrayOop.inline.hpp" 58 #include "oops/verifyOopClosure.hpp" 59 #include "prims/jvmtiDeferredUpdates.hpp" 60 #include "prims/jvmtiExport.hpp" 61 #include "prims/jvmtiThreadState.hpp" 62 #include "prims/methodHandles.hpp" 63 #include "prims/vectorSupport.hpp" 64 #include "runtime/atomicAccess.hpp" 65 #include "runtime/basicLock.inline.hpp" 66 #include "runtime/continuation.hpp" 67 #include "runtime/continuationEntry.inline.hpp" 68 #include "runtime/deoptimization.hpp" 69 #include "runtime/escapeBarrier.hpp" 70 #include "runtime/fieldDescriptor.inline.hpp" 71 #include "runtime/frame.inline.hpp" 72 #include "runtime/handles.inline.hpp" 73 #include "runtime/interfaceSupport.inline.hpp" 74 #include "runtime/javaThread.hpp" 75 #include "runtime/jniHandles.inline.hpp" 76 #include "runtime/keepStackGCProcessed.hpp" 77 #include "runtime/lightweightSynchronizer.hpp" 78 #include "runtime/lockStack.inline.hpp" 79 #include "runtime/objectMonitor.inline.hpp" 80 #include "runtime/osThread.hpp" 81 #include "runtime/safepointVerifiers.hpp" 82 #include "runtime/sharedRuntime.hpp" 83 #include "runtime/signature.hpp" 84 #include "runtime/stackFrameStream.inline.hpp" 85 #include "runtime/stackValue.hpp" 86 #include "runtime/stackWatermarkSet.hpp" 87 #include "runtime/stubRoutines.hpp" 88 #include "runtime/synchronizer.inline.hpp" 89 #include "runtime/threadSMR.hpp" 90 #include "runtime/threadWXSetters.inline.hpp" 91 #include "runtime/vframe.hpp" 92 #include "runtime/vframe_hp.hpp" 93 #include "runtime/vframeArray.hpp" 94 #include "runtime/vmOperations.hpp" 95 #include "utilities/checkedCast.hpp" 96 #include "utilities/events.hpp" 97 #include "utilities/growableArray.hpp" 98 #include "utilities/macros.hpp" 99 #include "utilities/preserveException.hpp" 100 #include "utilities/xmlstream.hpp" 101 #if INCLUDE_JFR 102 #include "jfr/jfr.inline.hpp" 103 #include "jfr/jfrEvents.hpp" 104 #include "jfr/metadata/jfrSerializer.hpp" 105 #endif 106 107 uint64_t DeoptimizationScope::_committed_deopt_gen = 0; 108 uint64_t DeoptimizationScope::_active_deopt_gen = 1; 109 bool DeoptimizationScope::_committing_in_progress = false; 110 111 DeoptimizationScope::DeoptimizationScope() : _required_gen(0) { 112 DEBUG_ONLY(_deopted = false;) 113 114 MutexLocker ml(NMethodState_lock, Mutex::_no_safepoint_check_flag); 115 // If there is nothing to deopt _required_gen is the same as comitted. 116 _required_gen = DeoptimizationScope::_committed_deopt_gen; 117 } 118 119 DeoptimizationScope::~DeoptimizationScope() { 120 assert(_deopted, "Deopt not executed"); 121 } 122 123 void DeoptimizationScope::mark(nmethod* nm, bool inc_recompile_counts) { 124 if (!nm->can_be_deoptimized()) { 125 return; 126 } 127 128 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 129 130 // If it's already marked but we still need it to be deopted. 131 if (nm->is_marked_for_deoptimization()) { 132 dependent(nm); 133 return; 134 } 135 136 nmethod::DeoptimizationStatus status = 137 inc_recompile_counts ? nmethod::deoptimize : nmethod::deoptimize_noupdate; 138 AtomicAccess::store(&nm->_deoptimization_status, status); 139 140 // Make sure active is not committed 141 assert(DeoptimizationScope::_committed_deopt_gen < DeoptimizationScope::_active_deopt_gen, "Must be"); 142 assert(nm->_deoptimization_generation == 0, "Is already marked"); 143 144 nm->_deoptimization_generation = DeoptimizationScope::_active_deopt_gen; 145 _required_gen = DeoptimizationScope::_active_deopt_gen; 146 } 147 148 void DeoptimizationScope::dependent(nmethod* nm) { 149 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 150 151 // A method marked by someone else may have a _required_gen lower than what we marked with. 152 // Therefore only store it if it's higher than _required_gen. 153 if (_required_gen < nm->_deoptimization_generation) { 154 _required_gen = nm->_deoptimization_generation; 155 } 156 } 157 158 void DeoptimizationScope::deoptimize_marked() { 159 assert(!_deopted, "Already deopted"); 160 161 // We are not alive yet. 162 if (!Universe::is_fully_initialized()) { 163 DEBUG_ONLY(_deopted = true;) 164 return; 165 } 166 167 // Safepoints are a special case, handled here. 168 if (SafepointSynchronize::is_at_safepoint()) { 169 DeoptimizationScope::_committed_deopt_gen = DeoptimizationScope::_active_deopt_gen; 170 DeoptimizationScope::_active_deopt_gen++; 171 Deoptimization::deoptimize_all_marked(); 172 DEBUG_ONLY(_deopted = true;) 173 return; 174 } 175 176 uint64_t comitting = 0; 177 bool wait = false; 178 while (true) { 179 { 180 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 181 182 // First we check if we or someone else already deopted the gen we want. 183 if (DeoptimizationScope::_committed_deopt_gen >= _required_gen) { 184 DEBUG_ONLY(_deopted = true;) 185 return; 186 } 187 if (!_committing_in_progress) { 188 // The version we are about to commit. 189 comitting = DeoptimizationScope::_active_deopt_gen; 190 // Make sure new marks use a higher gen. 191 DeoptimizationScope::_active_deopt_gen++; 192 _committing_in_progress = true; 193 wait = false; 194 } else { 195 // Another thread is handshaking and committing a gen. 196 wait = true; 197 } 198 } 199 if (wait) { 200 // Wait and let the concurrent handshake be performed. 201 ThreadBlockInVM tbivm(JavaThread::current()); 202 os::naked_yield(); 203 } else { 204 // Performs the handshake. 205 Deoptimization::deoptimize_all_marked(); // May safepoint and an additional deopt may have occurred. 206 DEBUG_ONLY(_deopted = true;) 207 { 208 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 209 210 // Make sure that committed doesn't go backwards. 211 // Should only happen if we did a deopt during a safepoint above. 212 if (DeoptimizationScope::_committed_deopt_gen < comitting) { 213 DeoptimizationScope::_committed_deopt_gen = comitting; 214 } 215 _committing_in_progress = false; 216 217 assert(DeoptimizationScope::_committed_deopt_gen >= _required_gen, "Must be"); 218 219 return; 220 } 221 } 222 } 223 } 224 225 Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame, 226 int caller_adjustment, 227 int caller_actual_parameters, 228 int number_of_frames, 229 intptr_t* frame_sizes, 230 address* frame_pcs, 231 BasicType return_type, 232 int exec_mode) { 233 _size_of_deoptimized_frame = size_of_deoptimized_frame; 234 _caller_adjustment = caller_adjustment; 235 _caller_actual_parameters = caller_actual_parameters; 236 _number_of_frames = number_of_frames; 237 _frame_sizes = frame_sizes; 238 _frame_pcs = frame_pcs; 239 _register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler); 240 _return_type = return_type; 241 _initial_info = 0; 242 // PD (x86 only) 243 _counter_temp = 0; 244 _unpack_kind = exec_mode; 245 _sender_sp_temp = 0; 246 247 _total_frame_sizes = size_of_frames(); 248 assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode"); 249 } 250 251 Deoptimization::UnrollBlock::~UnrollBlock() { 252 FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes); 253 FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs); 254 FREE_C_HEAP_ARRAY(intptr_t, _register_block); 255 } 256 257 int Deoptimization::UnrollBlock::size_of_frames() const { 258 // Account first for the adjustment of the initial frame 259 intptr_t result = _caller_adjustment; 260 for (int index = 0; index < number_of_frames(); index++) { 261 result += frame_sizes()[index]; 262 } 263 return checked_cast<int>(result); 264 } 265 266 void Deoptimization::UnrollBlock::print() { 267 ResourceMark rm; 268 stringStream st; 269 st.print_cr("UnrollBlock"); 270 st.print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame); 271 st.print( " frame_sizes: "); 272 for (int index = 0; index < number_of_frames(); index++) { 273 st.print("%zd ", frame_sizes()[index]); 274 } 275 st.cr(); 276 tty->print_raw(st.freeze()); 277 } 278 279 // In order to make fetch_unroll_info work properly with escape 280 // analysis, the method was changed from JRT_LEAF to JRT_BLOCK_ENTRY. 281 // The actual reallocation of previously eliminated objects occurs in realloc_objects, 282 // which is called from the method fetch_unroll_info_helper below. 283 JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* current, int exec_mode)) 284 // fetch_unroll_info() is called at the beginning of the deoptimization 285 // handler. Note this fact before we start generating temporary frames 286 // that can confuse an asynchronous stack walker. This counter is 287 // decremented at the end of unpack_frames(). 288 current->inc_in_deopt_handler(); 289 290 if (exec_mode == Unpack_exception) { 291 // When we get here, a callee has thrown an exception into a deoptimized 292 // frame. That throw might have deferred stack watermark checking until 293 // after unwinding. So we deal with such deferred requests here. 294 StackWatermarkSet::after_unwind(current); 295 } 296 297 return fetch_unroll_info_helper(current, exec_mode); 298 JRT_END 299 300 #if COMPILER2_OR_JVMCI 301 // print information about reallocated objects 302 static void print_objects(JavaThread* deoptee_thread, 303 GrowableArray<ScopeValue*>* objects, bool realloc_failures) { 304 ResourceMark rm; 305 stringStream st; // change to logStream with logging 306 st.print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(deoptee_thread)); 307 fieldDescriptor fd; 308 309 for (int i = 0; i < objects->length(); i++) { 310 ObjectValue* sv = (ObjectValue*) objects->at(i); 311 Handle obj = sv->value(); 312 313 if (obj.is_null()) { 314 st.print_cr(" nullptr"); 315 continue; 316 } 317 318 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()); 319 320 st.print(" object <" INTPTR_FORMAT "> of type ", p2i(sv->value()())); 321 k->print_value_on(&st); 322 st.print_cr(" allocated (%zu bytes)", obj->size() * HeapWordSize); 323 324 if (Verbose && k != nullptr) { 325 k->oop_print_on(obj(), &st); 326 } 327 } 328 tty->print_raw(st.freeze()); 329 } 330 331 static bool rematerialize_objects(JavaThread* thread, int exec_mode, nmethod* compiled_method, 332 frame& deoptee, RegisterMap& map, GrowableArray<compiledVFrame*>* chunk, 333 bool& deoptimized_objects) { 334 bool realloc_failures = false; 335 assert (chunk->at(0)->scope() != nullptr,"expect only compiled java frames"); 336 337 JavaThread* deoptee_thread = chunk->at(0)->thread(); 338 assert(exec_mode == Deoptimization::Unpack_none || (deoptee_thread == thread), 339 "a frame can only be deoptimized by the owner thread"); 340 341 GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects_to_rematerialize(deoptee, map); 342 343 // The flag return_oop() indicates call sites which return oop 344 // in compiled code. Such sites include java method calls, 345 // runtime calls (for example, used to allocate new objects/arrays 346 // on slow code path) and any other calls generated in compiled code. 347 // It is not guaranteed that we can get such information here only 348 // by analyzing bytecode in deoptimized frames. This is why this flag 349 // is set during method compilation (see Compile::Process_OopMap_Node()). 350 // If the previous frame was popped or if we are dispatching an exception, 351 // we don't have an oop result. 352 bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Deoptimization::Unpack_deopt); 353 Handle return_value; 354 if (save_oop_result) { 355 // Reallocation may trigger GC. If deoptimization happened on return from 356 // call which returns oop we need to save it since it is not in oopmap. 357 oop result = deoptee.saved_oop_result(&map); 358 assert(oopDesc::is_oop_or_null(result), "must be oop"); 359 return_value = Handle(thread, result); 360 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer"); 361 if (TraceDeoptimization) { 362 tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread)); 363 tty->cr(); 364 } 365 } 366 if (objects != nullptr) { 367 if (exec_mode == Deoptimization::Unpack_none) { 368 assert(thread->thread_state() == _thread_in_vm, "assumption"); 369 JavaThread* THREAD = thread; // For exception macros. 370 // Clear pending OOM if reallocation fails and return true indicating allocation failure 371 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, CHECK_AND_CLEAR_(true)); 372 deoptimized_objects = true; 373 } else { 374 JavaThread* current = thread; // For JRT_BLOCK 375 JRT_BLOCK 376 realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, THREAD); 377 JRT_END 378 } 379 guarantee(compiled_method != nullptr, "deopt must be associated with an nmethod"); 380 bool is_jvmci = compiled_method->is_compiled_by_jvmci(); 381 Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, is_jvmci); 382 if (TraceDeoptimization) { 383 print_objects(deoptee_thread, objects, realloc_failures); 384 } 385 } 386 if (save_oop_result) { 387 // Restore result. 388 deoptee.set_saved_oop_result(&map, return_value()); 389 } 390 return realloc_failures; 391 } 392 393 static void restore_eliminated_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures, 394 frame& deoptee, int exec_mode, bool& deoptimized_objects) { 395 JavaThread* deoptee_thread = chunk->at(0)->thread(); 396 assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once"); 397 assert(thread == Thread::current(), "should be"); 398 HandleMark hm(thread); 399 #ifndef PRODUCT 400 bool first = true; 401 #endif // !PRODUCT 402 // Start locking from outermost/oldest frame 403 for (int i = (chunk->length() - 1); i >= 0; i--) { 404 compiledVFrame* cvf = chunk->at(i); 405 assert (cvf->scope() != nullptr,"expect only compiled java frames"); 406 GrowableArray<MonitorInfo*>* monitors = cvf->monitors(); 407 if (monitors->is_nonempty()) { 408 bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee, 409 exec_mode, realloc_failures); 410 deoptimized_objects = deoptimized_objects || relocked; 411 #ifndef PRODUCT 412 if (PrintDeoptimizationDetails) { 413 ResourceMark rm; 414 stringStream st; 415 for (int j = 0; j < monitors->length(); j++) { 416 MonitorInfo* mi = monitors->at(j); 417 if (mi->eliminated()) { 418 if (first) { 419 first = false; 420 st.print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread)); 421 } 422 if (exec_mode == Deoptimization::Unpack_none) { 423 ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor(); 424 if (monitor != nullptr && monitor->object() == mi->owner()) { 425 st.print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner())); 426 continue; 427 } 428 } 429 if (mi->owner_is_scalar_replaced()) { 430 Klass* k = java_lang_Class::as_Klass(mi->owner_klass()); 431 st.print_cr(" failed reallocation for klass %s", k->external_name()); 432 } else { 433 st.print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner())); 434 } 435 } 436 } 437 tty->print_raw(st.freeze()); 438 } 439 #endif // !PRODUCT 440 } 441 } 442 } 443 444 // Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI. 445 // The given vframes cover one physical frame. 446 bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, 447 bool& realloc_failures) { 448 frame deoptee = chunk->at(0)->fr(); 449 JavaThread* deoptee_thread = chunk->at(0)->thread(); 450 nmethod* nm = deoptee.cb()->as_nmethod_or_null(); 451 RegisterMap map(chunk->at(0)->register_map()); 452 bool deoptimized_objects = false; 453 454 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false); 455 456 // Reallocate the non-escaping objects and restore their fields. 457 if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations) 458 || EliminateAutoBox || EnableVectorAggressiveReboxing)) { 459 realloc_failures = rematerialize_objects(thread, Unpack_none, nm, deoptee, map, chunk, deoptimized_objects); 460 } 461 462 // MonitorInfo structures used in eliminate_locks are not GC safe. 463 NoSafepointVerifier no_safepoint; 464 465 // Now relock objects if synchronization on them was eliminated. 466 if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) { 467 restore_eliminated_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects); 468 } 469 return deoptimized_objects; 470 } 471 #endif // COMPILER2_OR_JVMCI 472 473 // This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap) 474 Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* current, int exec_mode) { 475 JFR_ONLY(Jfr::check_and_process_sample_request(current);) 476 // When we get here we are about to unwind the deoptee frame. In order to 477 // catch not yet safe to use frames, the following stack watermark barrier 478 // poll will make such frames safe to use. 479 StackWatermarkSet::before_unwind(current); 480 481 // Note: there is a safepoint safety issue here. No matter whether we enter 482 // via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once 483 // the vframeArray is created. 484 // 485 486 // Allocate our special deoptimization ResourceMark 487 DeoptResourceMark* dmark = new DeoptResourceMark(current); 488 assert(current->deopt_mark() == nullptr, "Pending deopt!"); 489 current->set_deopt_mark(dmark); 490 491 frame stub_frame = current->last_frame(); // Makes stack walkable as side effect 492 RegisterMap map(current, 493 RegisterMap::UpdateMap::include, 494 RegisterMap::ProcessFrames::include, 495 RegisterMap::WalkContinuation::skip); 496 RegisterMap dummy_map(current, 497 RegisterMap::UpdateMap::skip, 498 RegisterMap::ProcessFrames::include, 499 RegisterMap::WalkContinuation::skip); 500 // Now get the deoptee with a valid map 501 frame deoptee = stub_frame.sender(&map); 502 // Set the deoptee nmethod 503 assert(current->deopt_compiled_method() == nullptr, "Pending deopt!"); 504 nmethod* nm = deoptee.cb()->as_nmethod_or_null(); 505 current->set_deopt_compiled_method(nm); 506 507 if (VerifyStack) { 508 current->validate_frame_layout(); 509 } 510 511 // Create a growable array of VFrames where each VFrame represents an inlined 512 // Java frame. This storage is allocated with the usual system arena. 513 assert(deoptee.is_compiled_frame(), "Wrong frame type"); 514 GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10); 515 vframe* vf = vframe::new_vframe(&deoptee, &map, current); 516 while (!vf->is_top()) { 517 assert(vf->is_compiled_frame(), "Wrong frame type"); 518 chunk->push(compiledVFrame::cast(vf)); 519 vf = vf->sender(); 520 } 521 assert(vf->is_compiled_frame(), "Wrong frame type"); 522 chunk->push(compiledVFrame::cast(vf)); 523 524 bool realloc_failures = false; 525 526 #if COMPILER2_OR_JVMCI 527 bool const jvmci_enabled = JVMCI_ONLY(EnableJVMCI) NOT_JVMCI(false); 528 529 // Reallocate the non-escaping objects and restore their fields. Then 530 // relock objects if synchronization on them was eliminated. 531 if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations) 532 || EliminateAutoBox || EnableVectorAggressiveReboxing )) { 533 bool unused; 534 realloc_failures = rematerialize_objects(current, exec_mode, nm, deoptee, map, chunk, unused); 535 } 536 #endif // COMPILER2_OR_JVMCI 537 538 // Ensure that no safepoint is taken after pointers have been stored 539 // in fields of rematerialized objects. If a safepoint occurs from here on 540 // out the java state residing in the vframeArray will be missed. 541 // Locks may be rebaised in a safepoint. 542 NoSafepointVerifier no_safepoint; 543 544 #if COMPILER2_OR_JVMCI 545 if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) )) 546 && !EscapeBarrier::objs_are_deoptimized(current, deoptee.id())) { 547 bool unused = false; 548 restore_eliminated_locks(current, chunk, realloc_failures, deoptee, exec_mode, unused); 549 } 550 #endif // COMPILER2_OR_JVMCI 551 552 ScopeDesc* trap_scope = chunk->at(0)->scope(); 553 Handle exceptionObject; 554 if (trap_scope->rethrow_exception()) { 555 #ifndef PRODUCT 556 if (PrintDeoptimizationDetails) { 557 tty->print_cr("Exception to be rethrown in the interpreter for method %s::%s at bci %d", trap_scope->method()->method_holder()->name()->as_C_string(), trap_scope->method()->name()->as_C_string(), trap_scope->bci()); 558 } 559 #endif // !PRODUCT 560 561 GrowableArray<ScopeValue*>* expressions = trap_scope->expressions(); 562 guarantee(expressions != nullptr && expressions->length() == 1, "should have only exception on stack"); 563 guarantee(exec_mode != Unpack_exception, "rethrow_exception set with Unpack_exception"); 564 ScopeValue* topOfStack = expressions->top(); 565 exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj(); 566 guarantee(exceptionObject() != nullptr, "exception oop can not be null"); 567 } 568 569 vframeArray* array = create_vframeArray(current, deoptee, &map, chunk, realloc_failures); 570 #if COMPILER2_OR_JVMCI 571 if (realloc_failures) { 572 // This destroys all ScopedValue bindings. 573 current->clear_scopedValueBindings(); 574 pop_frames_failed_reallocs(current, array); 575 } 576 #endif 577 578 assert(current->vframe_array_head() == nullptr, "Pending deopt!"); 579 current->set_vframe_array_head(array); 580 581 // Now that the vframeArray has been created if we have any deferred local writes 582 // added by jvmti then we can free up that structure as the data is now in the 583 // vframeArray 584 585 JvmtiDeferredUpdates::delete_updates_for_frame(current, array->original().id()); 586 587 // Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info. 588 CodeBlob* cb = stub_frame.cb(); 589 // Verify we have the right vframeArray 590 assert(cb->frame_size() >= 0, "Unexpected frame size"); 591 intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size(); 592 593 // If the deopt call site is a MethodHandle invoke call site we have 594 // to adjust the unpack_sp. 595 nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null(); 596 if (deoptee_nm != nullptr && deoptee_nm->is_method_handle_return(deoptee.pc())) 597 unpack_sp = deoptee.unextended_sp(); 598 599 #ifdef ASSERT 600 assert(cb->is_deoptimization_stub() || 601 cb->is_uncommon_trap_stub() || 602 strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 || 603 strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0, 604 "unexpected code blob: %s", cb->name()); 605 #endif 606 607 // This is a guarantee instead of an assert because if vframe doesn't match 608 // we will unpack the wrong deoptimized frame and wind up in strange places 609 // where it will be very difficult to figure out what went wrong. Better 610 // to die an early death here than some very obscure death later when the 611 // trail is cold. 612 guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack"); 613 614 int number_of_frames = array->frames(); 615 616 // Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost 617 // virtual activation, which is the reverse of the elements in the vframes array. 618 intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler); 619 // +1 because we always have an interpreter return address for the final slot. 620 address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler); 621 int popframe_extra_args = 0; 622 // Create an interpreter return address for the stub to use as its return 623 // address so the skeletal frames are perfectly walkable 624 frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0); 625 626 // PopFrame requires that the preserved incoming arguments from the recently-popped topmost 627 // activation be put back on the expression stack of the caller for reexecution 628 if (JvmtiExport::can_pop_frame() && current->popframe_forcing_deopt_reexecution()) { 629 popframe_extra_args = in_words(current->popframe_preserved_args_size_in_words()); 630 } 631 632 // Find the current pc for sender of the deoptee. Since the sender may have been deoptimized 633 // itself since the deoptee vframeArray was created we must get a fresh value of the pc rather 634 // than simply use array->sender.pc(). This requires us to walk the current set of frames 635 // 636 frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame 637 deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller 638 639 // It's possible that the number of parameters at the call site is 640 // different than number of arguments in the callee when method 641 // handles are used. If the caller is interpreted get the real 642 // value so that the proper amount of space can be added to it's 643 // frame. 644 bool caller_was_method_handle = false; 645 if (deopt_sender.is_interpreted_frame()) { 646 methodHandle method(current, deopt_sender.interpreter_frame_method()); 647 Bytecode_invoke cur(method, deopt_sender.interpreter_frame_bci()); 648 if (cur.has_member_arg()) { 649 // This should cover all real-world cases. One exception is a pathological chain of 650 // MH.linkToXXX() linker calls, which only trusted code could do anyway. To handle that case, we 651 // would need to get the size from the resolved method entry. Another exception would 652 // be an invokedynamic with an adapter that is really a MethodHandle linker. 653 caller_was_method_handle = true; 654 } 655 } 656 657 // 658 // frame_sizes/frame_pcs[0] oldest frame (int or c2i) 659 // frame_sizes/frame_pcs[1] next oldest frame (int) 660 // frame_sizes/frame_pcs[n] youngest frame (int) 661 // 662 // Now a pc in frame_pcs is actually the return address to the frame's caller (a frame 663 // owns the space for the return address to it's caller). Confusing ain't it. 664 // 665 // The vframe array can address vframes with indices running from 666 // 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame. 667 // When we create the skeletal frames we need the oldest frame to be in the zero slot 668 // in the frame_sizes/frame_pcs so the assembly code can do a trivial walk. 669 // so things look a little strange in this loop. 670 // 671 int callee_parameters = 0; 672 int callee_locals = 0; 673 for (int index = 0; index < array->frames(); index++ ) { 674 // frame[number_of_frames - 1 ] = on_stack_size(youngest) 675 // frame[number_of_frames - 2 ] = on_stack_size(sender(youngest)) 676 // frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest))) 677 frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters, 678 callee_locals, 679 index == 0, 680 popframe_extra_args); 681 // This pc doesn't have to be perfect just good enough to identify the frame 682 // as interpreted so the skeleton frame will be walkable 683 // The correct pc will be set when the skeleton frame is completely filled out 684 // The final pc we store in the loop is wrong and will be overwritten below 685 frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset; 686 687 callee_parameters = array->element(index)->method()->size_of_parameters(); 688 callee_locals = array->element(index)->method()->max_locals(); 689 popframe_extra_args = 0; 690 } 691 692 // Compute whether the root vframe returns a float or double value. 693 BasicType return_type; 694 { 695 methodHandle method(current, array->element(0)->method()); 696 Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci()); 697 return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL; 698 } 699 700 // Compute information for handling adapters and adjusting the frame size of the caller. 701 int caller_adjustment = 0; 702 703 // Compute the amount the oldest interpreter frame will have to adjust 704 // its caller's stack by. If the caller is a compiled frame then 705 // we pretend that the callee has no parameters so that the 706 // extension counts for the full amount of locals and not just 707 // locals-parms. This is because without a c2i adapter the parm 708 // area as created by the compiled frame will not be usable by 709 // the interpreter. (Depending on the calling convention there 710 // may not even be enough space). 711 712 // QQQ I'd rather see this pushed down into last_frame_adjust 713 // and have it take the sender (aka caller). 714 715 if (!deopt_sender.is_interpreted_frame() || caller_was_method_handle) { 716 caller_adjustment = last_frame_adjust(0, callee_locals); 717 } else if (callee_locals > callee_parameters) { 718 // The caller frame may need extending to accommodate 719 // non-parameter locals of the first unpacked interpreted frame. 720 // Compute that adjustment. 721 caller_adjustment = last_frame_adjust(callee_parameters, callee_locals); 722 } 723 724 // If the sender is deoptimized the we must retrieve the address of the handler 725 // since the frame will "magically" show the original pc before the deopt 726 // and we'd undo the deopt. 727 728 frame_pcs[0] = Continuation::is_cont_barrier_frame(deoptee) ? StubRoutines::cont_returnBarrier() : deopt_sender.raw_pc(); 729 if (Continuation::is_continuation_enterSpecial(deopt_sender)) { 730 ContinuationEntry::from_frame(deopt_sender)->set_argsize(0); 731 } 732 733 assert(CodeCache::find_blob(frame_pcs[0]) != nullptr, "bad pc"); 734 735 #if INCLUDE_JVMCI 736 if (exceptionObject() != nullptr) { 737 current->set_exception_oop(exceptionObject()); 738 exec_mode = Unpack_exception; 739 assert(array->element(0)->rethrow_exception(), "must be"); 740 } 741 #endif 742 743 if (current->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) { 744 assert(current->has_pending_exception(), "should have thrown OOME"); 745 current->set_exception_oop(current->pending_exception()); 746 current->clear_pending_exception(); 747 exec_mode = Unpack_exception; 748 } 749 750 #if INCLUDE_JVMCI 751 if (current->frames_to_pop_failed_realloc() > 0) { 752 current->set_pending_monitorenter(false); 753 } 754 #endif 755 756 int caller_actual_parameters = -1; // value not used except for interpreted frames, see below 757 if (deopt_sender.is_interpreted_frame()) { 758 caller_actual_parameters = callee_parameters + (caller_was_method_handle ? 1 : 0); 759 } 760 761 UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord, 762 caller_adjustment * BytesPerWord, 763 caller_actual_parameters, 764 number_of_frames, 765 frame_sizes, 766 frame_pcs, 767 return_type, 768 exec_mode); 769 // On some platforms, we need a way to pass some platform dependent 770 // information to the unpacking code so the skeletal frames come out 771 // correct (initial fp value, unextended sp, ...) 772 info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info()); 773 774 if (array->frames() > 1) { 775 if (VerifyStack && TraceDeoptimization) { 776 tty->print_cr("Deoptimizing method containing inlining"); 777 } 778 } 779 780 array->set_unroll_block(info); 781 return info; 782 } 783 784 // Called to cleanup deoptimization data structures in normal case 785 // after unpacking to stack and when stack overflow error occurs 786 void Deoptimization::cleanup_deopt_info(JavaThread *thread, 787 vframeArray *array) { 788 789 // Get array if coming from exception 790 if (array == nullptr) { 791 array = thread->vframe_array_head(); 792 } 793 thread->set_vframe_array_head(nullptr); 794 795 // Free the previous UnrollBlock 796 vframeArray* old_array = thread->vframe_array_last(); 797 thread->set_vframe_array_last(array); 798 799 if (old_array != nullptr) { 800 UnrollBlock* old_info = old_array->unroll_block(); 801 old_array->set_unroll_block(nullptr); 802 delete old_info; 803 delete old_array; 804 } 805 806 // Deallocate any resource creating in this routine and any ResourceObjs allocated 807 // inside the vframeArray (StackValueCollections) 808 809 delete thread->deopt_mark(); 810 thread->set_deopt_mark(nullptr); 811 thread->set_deopt_compiled_method(nullptr); 812 813 814 if (JvmtiExport::can_pop_frame()) { 815 // Regardless of whether we entered this routine with the pending 816 // popframe condition bit set, we should always clear it now 817 thread->clear_popframe_condition(); 818 } 819 820 // unpack_frames() is called at the end of the deoptimization handler 821 // and (in C2) at the end of the uncommon trap handler. Note this fact 822 // so that an asynchronous stack walker can work again. This counter is 823 // incremented at the beginning of fetch_unroll_info() and (in C2) at 824 // the beginning of uncommon_trap(). 825 thread->dec_in_deopt_handler(); 826 } 827 828 // Moved from cpu directories because none of the cpus has callee save values. 829 // If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp. 830 void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) { 831 832 // This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in 833 // the days we had adapter frames. When we deoptimize a situation where a 834 // compiled caller calls a compiled caller will have registers it expects 835 // to survive the call to the callee. If we deoptimize the callee the only 836 // way we can restore these registers is to have the oldest interpreter 837 // frame that we create restore these values. That is what this routine 838 // will accomplish. 839 840 // At the moment we have modified c2 to not have any callee save registers 841 // so this problem does not exist and this routine is just a place holder. 842 843 assert(f->is_interpreted_frame(), "must be interpreted"); 844 } 845 846 #ifndef PRODUCT 847 #ifdef ASSERT 848 // Return true if the execution after the provided bytecode continues at the 849 // next bytecode in the code. This is not the case for gotos, returns, and 850 // throws. 851 static bool falls_through(Bytecodes::Code bc) { 852 switch (bc) { 853 case Bytecodes::_goto: 854 case Bytecodes::_goto_w: 855 case Bytecodes::_athrow: 856 case Bytecodes::_areturn: 857 case Bytecodes::_dreturn: 858 case Bytecodes::_freturn: 859 case Bytecodes::_ireturn: 860 case Bytecodes::_lreturn: 861 case Bytecodes::_jsr: 862 case Bytecodes::_ret: 863 case Bytecodes::_return: 864 case Bytecodes::_lookupswitch: 865 case Bytecodes::_tableswitch: 866 return false; 867 default: 868 return true; 869 } 870 } 871 #endif 872 #endif 873 874 // Return BasicType of value being returned 875 JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)) 876 assert(thread == JavaThread::current(), "pre-condition"); 877 878 // We are already active in the special DeoptResourceMark any ResourceObj's we 879 // allocate will be freed at the end of the routine. 880 881 // JRT_LEAF methods don't normally allocate handles and there is a 882 // NoHandleMark to enforce that. It is actually safe to use Handles 883 // in a JRT_LEAF method, and sometimes desirable, but to do so we 884 // must use ResetNoHandleMark to bypass the NoHandleMark, and 885 // then use a HandleMark to ensure any Handles we do create are 886 // cleaned up in this scope. 887 ResetNoHandleMark rnhm; 888 HandleMark hm(thread); 889 890 frame stub_frame = thread->last_frame(); 891 892 Continuation::notify_deopt(thread, stub_frame.sp()); 893 894 // Since the frame to unpack is the top frame of this thread, the vframe_array_head 895 // must point to the vframeArray for the unpack frame. 896 vframeArray* array = thread->vframe_array_head(); 897 UnrollBlock* info = array->unroll_block(); 898 899 // We set the last_Java frame. But the stack isn't really parsable here. So we 900 // clear it to make sure JFR understands not to try and walk stacks from events 901 // in here. 902 intptr_t* sp = thread->frame_anchor()->last_Java_sp(); 903 thread->frame_anchor()->set_last_Java_sp(nullptr); 904 905 // Unpack the interpreter frames and any adapter frame (c2 only) we might create. 906 array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters()); 907 908 thread->frame_anchor()->set_last_Java_sp(sp); 909 910 BasicType bt = info->return_type(); 911 912 // If we have an exception pending, claim that the return type is an oop 913 // so the deopt_blob does not overwrite the exception_oop. 914 915 if (exec_mode == Unpack_exception) 916 bt = T_OBJECT; 917 918 // Cleanup thread deopt data 919 cleanup_deopt_info(thread, array); 920 921 #ifndef PRODUCT 922 if (VerifyStack) { 923 ResourceMark res_mark; 924 // Clear pending exception to not break verification code (restored afterwards) 925 PreserveExceptionMark pm(thread); 926 927 thread->validate_frame_layout(); 928 929 // Verify that the just-unpacked frames match the interpreter's 930 // notions of expression stack and locals 931 vframeArray* cur_array = thread->vframe_array_last(); 932 RegisterMap rm(thread, 933 RegisterMap::UpdateMap::skip, 934 RegisterMap::ProcessFrames::include, 935 RegisterMap::WalkContinuation::skip); 936 rm.set_include_argument_oops(false); 937 int callee_size_of_parameters = 0; 938 for (int frame_idx = 0; frame_idx < cur_array->frames(); frame_idx++) { 939 bool is_top_frame = (frame_idx == 0); 940 vframeArrayElement* el = cur_array->element(frame_idx); 941 frame* iframe = el->iframe(); 942 guarantee(iframe->is_interpreted_frame(), "Wrong frame type"); 943 methodHandle mh(thread, iframe->interpreter_frame_method()); 944 bool reexecute = el->should_reexecute(); 945 946 int cur_invoke_parameter_size = 0; 947 int top_frame_expression_stack_adjustment = 0; 948 int max_bci = mh->code_size(); 949 BytecodeStream str(mh, iframe->interpreter_frame_bci()); 950 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds"); 951 Bytecodes::Code cur_code = str.next(); 952 953 if (!reexecute && !Bytecodes::is_invoke(cur_code)) { 954 // We can only compute OopMaps for the before state, so we need to roll forward 955 // to the next bytecode. 956 assert(is_top_frame, "must be"); 957 assert(falls_through(cur_code), "must be"); 958 assert(cur_code != Bytecodes::_illegal, "illegal bytecode"); 959 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds"); 960 961 // Need to subtract off the size of the result type of 962 // the bytecode because this is not described in the 963 // debug info but returned to the interpreter in the TOS 964 // caching register 965 BasicType bytecode_result_type = Bytecodes::result_type(cur_code); 966 if (bytecode_result_type != T_ILLEGAL) { 967 top_frame_expression_stack_adjustment = type2size[bytecode_result_type]; 968 } 969 assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive"); 970 971 cur_code = str.next(); 972 // Reflect the fact that we have rolled forward and now need 973 // top_frame_expression_stack_adjustment 974 reexecute = true; 975 } 976 977 assert(cur_code != Bytecodes::_illegal, "illegal bytecode"); 978 assert(str.bci() < max_bci, "bci in interpreter frame out of bounds"); 979 980 // Get the oop map for this bci 981 InterpreterOopMap mask; 982 OopMapCache::compute_one_oop_map(mh, str.bci(), &mask); 983 // Check to see if we can grab the number of outgoing arguments 984 // at an uncommon trap for an invoke (where the compiler 985 // generates debug info before the invoke has executed) 986 if (Bytecodes::is_invoke(cur_code)) { 987 Bytecode_invoke invoke(mh, str.bci()); 988 cur_invoke_parameter_size = invoke.size_of_parameters(); 989 if (!is_top_frame && invoke.has_member_arg()) { 990 callee_size_of_parameters++; 991 } 992 } 993 994 // Verify stack depth and oops in frame 995 auto match = [&]() { 996 int iframe_expr_ssize = iframe->interpreter_frame_expression_stack_size(); 997 #if INCLUDE_JVMCI 998 if (is_top_frame && el->rethrow_exception()) { 999 return iframe_expr_ssize == 1; 1000 } 1001 #endif 1002 // This should only be needed for C1 1003 if (is_top_frame && exec_mode == Unpack_exception && iframe_expr_ssize == 0) { 1004 return true; 1005 } 1006 if (reexecute) { 1007 int expr_ssize_before = iframe_expr_ssize + top_frame_expression_stack_adjustment; 1008 int oopmap_expr_invoke_ssize = mask.expression_stack_size() + cur_invoke_parameter_size; 1009 return expr_ssize_before == oopmap_expr_invoke_ssize; 1010 } else { 1011 int oopmap_expr_callee_ssize = mask.expression_stack_size() + callee_size_of_parameters; 1012 return iframe_expr_ssize == oopmap_expr_callee_ssize; 1013 } 1014 }; 1015 if (!match()) { 1016 // Print out some information that will help us debug the problem 1017 tty->print_cr("Wrong number of expression stack elements during deoptimization"); 1018 tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", frame_idx, cur_array->frames() - 1); 1019 tty->print_cr(" Current code %s", Bytecodes::name(cur_code)); 1020 tty->print_cr(" Fabricated interpreter frame had %d expression stack elements", 1021 iframe->interpreter_frame_expression_stack_size()); 1022 tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size()); 1023 tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters); 1024 tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment); 1025 tty->print_cr(" exec_mode = %d", exec_mode); 1026 tty->print_cr(" original should_reexecute = %s", el->should_reexecute() ? "true" : "false"); 1027 tty->print_cr(" reexecute = %s%s", reexecute ? "true" : "false", 1028 (reexecute != el->should_reexecute()) ? " (changed)" : ""); 1029 #if INCLUDE_JVMCI 1030 tty->print_cr(" rethrow_exception = %s", el->rethrow_exception() ? "true" : "false"); 1031 #endif 1032 tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size); 1033 tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id()); 1034 tty->print_cr(" Interpreted frames:"); 1035 for (int k = 0; k < cur_array->frames(); k++) { 1036 vframeArrayElement* el = cur_array->element(k); 1037 tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci()); 1038 } 1039 cur_array->print_on_2(tty); 1040 guarantee(false, "wrong number of expression stack elements during deopt"); 1041 } 1042 VerifyOopClosure verify; 1043 iframe->oops_interpreted_do(&verify, &rm, false); 1044 callee_size_of_parameters = mh->size_of_parameters(); 1045 } 1046 } 1047 #endif // !PRODUCT 1048 1049 return bt; 1050 JRT_END 1051 1052 class DeoptimizeMarkedHandshakeClosure : public HandshakeClosure { 1053 public: 1054 DeoptimizeMarkedHandshakeClosure() : HandshakeClosure("Deoptimize") {} 1055 void do_thread(Thread* thread) { 1056 JavaThread* jt = JavaThread::cast(thread); 1057 jt->deoptimize_marked_methods(); 1058 } 1059 }; 1060 1061 void Deoptimization::deoptimize_all_marked() { 1062 ResourceMark rm; 1063 1064 // Make the dependent methods not entrant 1065 CodeCache::make_marked_nmethods_deoptimized(); 1066 1067 DeoptimizeMarkedHandshakeClosure deopt; 1068 if (SafepointSynchronize::is_at_safepoint()) { 1069 Threads::java_threads_do(&deopt); 1070 } else { 1071 Handshake::execute(&deopt); 1072 } 1073 } 1074 1075 Deoptimization::DeoptAction Deoptimization::_unloaded_action 1076 = Deoptimization::Action_reinterpret; 1077 1078 #if INCLUDE_JVMCI 1079 template<typename CacheType> 1080 class BoxCacheBase : public CHeapObj<mtCompiler> { 1081 protected: 1082 static InstanceKlass* find_cache_klass(Thread* thread, Symbol* klass_name) { 1083 ResourceMark rm(thread); 1084 char* klass_name_str = klass_name->as_C_string(); 1085 InstanceKlass* ik = SystemDictionary::find_instance_klass(thread, klass_name, Handle()); 1086 guarantee(ik != nullptr, "%s must be loaded", klass_name_str); 1087 if (!ik->is_in_error_state()) { 1088 guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str); 1089 CacheType::compute_offsets(ik); 1090 } 1091 return ik; 1092 } 1093 }; 1094 1095 template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> { 1096 PrimitiveType _low; 1097 PrimitiveType _high; 1098 jobject _cache; 1099 protected: 1100 static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton; 1101 BoxCache(Thread* thread) { 1102 InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(thread, CacheType::symbol()); 1103 if (ik->is_in_error_state()) { 1104 _low = 1; 1105 _high = 0; 1106 _cache = nullptr; 1107 } else { 1108 objArrayOop cache = CacheType::cache(ik); 1109 assert(cache->length() > 0, "Empty cache"); 1110 _low = BoxType::value(cache->obj_at(0)); 1111 _high = checked_cast<PrimitiveType>(_low + cache->length() - 1); 1112 _cache = JNIHandles::make_global(Handle(thread, cache)); 1113 } 1114 } 1115 ~BoxCache() { 1116 JNIHandles::destroy_global(_cache); 1117 } 1118 public: 1119 static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) { 1120 if (_singleton == nullptr) { 1121 BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread); 1122 if (!AtomicAccess::replace_if_null(&_singleton, s)) { 1123 delete s; 1124 } 1125 } 1126 return _singleton; 1127 } 1128 oop lookup(PrimitiveType value) { 1129 if (_low <= value && value <= _high) { 1130 int offset = checked_cast<int>(value - _low); 1131 return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset); 1132 } 1133 return nullptr; 1134 } 1135 oop lookup_raw(intptr_t raw_value, bool& cache_init_error) { 1136 if (_cache == nullptr) { 1137 cache_init_error = true; 1138 return nullptr; 1139 } 1140 // Have to cast to avoid little/big-endian problems. 1141 if (sizeof(PrimitiveType) > sizeof(jint)) { 1142 jlong value = (jlong)raw_value; 1143 return lookup(value); 1144 } 1145 PrimitiveType value = (PrimitiveType)*((jint*)&raw_value); 1146 return lookup(value); 1147 } 1148 }; 1149 1150 typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache; 1151 typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache; 1152 typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache; 1153 typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache; 1154 typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache; 1155 1156 template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = nullptr; 1157 template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = nullptr; 1158 template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = nullptr; 1159 template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = nullptr; 1160 template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = nullptr; 1161 1162 class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> { 1163 jobject _true_cache; 1164 jobject _false_cache; 1165 protected: 1166 static BooleanBoxCache *_singleton; 1167 BooleanBoxCache(Thread *thread) { 1168 InstanceKlass* ik = find_cache_klass(thread, java_lang_Boolean::symbol()); 1169 if (ik->is_in_error_state()) { 1170 _true_cache = nullptr; 1171 _false_cache = nullptr; 1172 } else { 1173 _true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik))); 1174 _false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik))); 1175 } 1176 } 1177 ~BooleanBoxCache() { 1178 JNIHandles::destroy_global(_true_cache); 1179 JNIHandles::destroy_global(_false_cache); 1180 } 1181 public: 1182 static BooleanBoxCache* singleton(Thread* thread) { 1183 if (_singleton == nullptr) { 1184 BooleanBoxCache* s = new BooleanBoxCache(thread); 1185 if (!AtomicAccess::replace_if_null(&_singleton, s)) { 1186 delete s; 1187 } 1188 } 1189 return _singleton; 1190 } 1191 oop lookup_raw(intptr_t raw_value, bool& cache_in_error) { 1192 if (_true_cache == nullptr) { 1193 cache_in_error = true; 1194 return nullptr; 1195 } 1196 // Have to cast to avoid little/big-endian problems. 1197 jboolean value = (jboolean)*((jint*)&raw_value); 1198 return lookup(value); 1199 } 1200 oop lookup(jboolean value) { 1201 if (value != 0) { 1202 return JNIHandles::resolve_non_null(_true_cache); 1203 } 1204 return JNIHandles::resolve_non_null(_false_cache); 1205 } 1206 }; 1207 1208 BooleanBoxCache* BooleanBoxCache::_singleton = nullptr; 1209 1210 oop Deoptimization::get_cached_box(AutoBoxObjectValue* bv, frame* fr, RegisterMap* reg_map, bool& cache_init_error, TRAPS) { 1211 Klass* k = java_lang_Class::as_Klass(bv->klass()->as_ConstantOopReadValue()->value()()); 1212 BasicType box_type = vmClasses::box_klass_type(k); 1213 if (box_type != T_OBJECT) { 1214 StackValue* value = StackValue::create_stack_value(fr, reg_map, bv->field_at(box_type == T_LONG ? 1 : 0)); 1215 switch(box_type) { 1216 case T_INT: return IntegerBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error); 1217 case T_CHAR: return CharacterBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error); 1218 case T_SHORT: return ShortBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error); 1219 case T_BYTE: return ByteBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error); 1220 case T_BOOLEAN: return BooleanBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error); 1221 case T_LONG: return LongBoxCache::singleton(THREAD)->lookup_raw(value->get_intptr(), cache_init_error); 1222 default:; 1223 } 1224 } 1225 return nullptr; 1226 } 1227 #endif // INCLUDE_JVMCI 1228 1229 #if COMPILER2_OR_JVMCI 1230 bool Deoptimization::realloc_objects(JavaThread* thread, frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, TRAPS) { 1231 Handle pending_exception(THREAD, thread->pending_exception()); 1232 const char* exception_file = thread->exception_file(); 1233 int exception_line = thread->exception_line(); 1234 thread->clear_pending_exception(); 1235 1236 bool failures = false; 1237 1238 for (int i = 0; i < objects->length(); i++) { 1239 assert(objects->at(i)->is_object(), "invalid debug information"); 1240 ObjectValue* sv = (ObjectValue*) objects->at(i); 1241 1242 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()); 1243 oop obj = nullptr; 1244 1245 bool cache_init_error = false; 1246 if (k->is_instance_klass()) { 1247 #if INCLUDE_JVMCI 1248 nmethod* nm = fr->cb()->as_nmethod_or_null(); 1249 if (nm->is_compiled_by_jvmci() && sv->is_auto_box()) { 1250 AutoBoxObjectValue* abv = (AutoBoxObjectValue*) sv; 1251 obj = get_cached_box(abv, fr, reg_map, cache_init_error, THREAD); 1252 if (obj != nullptr) { 1253 // Set the flag to indicate the box came from a cache, so that we can skip the field reassignment for it. 1254 abv->set_cached(true); 1255 } else if (cache_init_error) { 1256 // Results in an OOME which is valid (as opposed to a class initialization error) 1257 // and is fine for the rare case a cache initialization failing. 1258 failures = true; 1259 } 1260 } 1261 #endif // INCLUDE_JVMCI 1262 1263 InstanceKlass* ik = InstanceKlass::cast(k); 1264 if (obj == nullptr && !cache_init_error) { 1265 InternalOOMEMark iom(THREAD); 1266 if (EnableVectorSupport && VectorSupport::is_vector(ik)) { 1267 obj = VectorSupport::allocate_vector(ik, fr, reg_map, sv, THREAD); 1268 } else { 1269 obj = ik->allocate_instance(THREAD); 1270 } 1271 } 1272 } else if (k->is_typeArray_klass()) { 1273 TypeArrayKlass* ak = TypeArrayKlass::cast(k); 1274 assert(sv->field_size() % type2size[ak->element_type()] == 0, "non-integral array length"); 1275 int len = sv->field_size() / type2size[ak->element_type()]; 1276 InternalOOMEMark iom(THREAD); 1277 obj = ak->allocate_instance(len, THREAD); 1278 } else if (k->is_objArray_klass()) { 1279 ObjArrayKlass* ak = ObjArrayKlass::cast(k); 1280 InternalOOMEMark iom(THREAD); 1281 obj = ak->allocate_instance(sv->field_size(), THREAD); 1282 } 1283 1284 if (obj == nullptr) { 1285 failures = true; 1286 } 1287 1288 assert(sv->value().is_null(), "redundant reallocation"); 1289 assert(obj != nullptr || HAS_PENDING_EXCEPTION || cache_init_error, "allocation should succeed or we should get an exception"); 1290 CLEAR_PENDING_EXCEPTION; 1291 sv->set_value(obj); 1292 } 1293 1294 if (failures) { 1295 THROW_OOP_(Universe::out_of_memory_error_realloc_objects(), failures); 1296 } else if (pending_exception.not_null()) { 1297 thread->set_pending_exception(pending_exception(), exception_file, exception_line); 1298 } 1299 1300 return failures; 1301 } 1302 1303 #if INCLUDE_JVMCI 1304 /** 1305 * For primitive types whose kind gets "erased" at runtime (shorts become stack ints), 1306 * we need to somehow be able to recover the actual kind to be able to write the correct 1307 * amount of bytes. 1308 * For that purpose, this method assumes that, for an entry spanning n bytes at index i, 1309 * the entries at index n + 1 to n + i are 'markers'. 1310 * For example, if we were writing a short at index 4 of a byte array of size 8, the 1311 * expected form of the array would be: 1312 * 1313 * {b0, b1, b2, b3, INT, marker, b6, b7} 1314 * 1315 * Thus, in order to get back the size of the entry, we simply need to count the number 1316 * of marked entries 1317 * 1318 * @param virtualArray the virtualized byte array 1319 * @param i index of the virtual entry we are recovering 1320 * @return The number of bytes the entry spans 1321 */ 1322 static int count_number_of_bytes_for_entry(ObjectValue *virtualArray, int i) { 1323 int index = i; 1324 while (++index < virtualArray->field_size() && 1325 virtualArray->field_at(index)->is_marker()) {} 1326 return index - i; 1327 } 1328 1329 /** 1330 * If there was a guarantee for byte array to always start aligned to a long, we could 1331 * do a simple check on the parity of the index. Unfortunately, that is not always the 1332 * case. Thus, we check alignment of the actual address we are writing to. 1333 * In the unlikely case index 0 is 5-aligned for example, it would then be possible to 1334 * write a long to index 3. 1335 */ 1336 static jbyte* check_alignment_get_addr(typeArrayOop obj, int index, int expected_alignment) { 1337 jbyte* res = obj->byte_at_addr(index); 1338 assert((((intptr_t) res) % expected_alignment) == 0, "Non-aligned write"); 1339 return res; 1340 } 1341 1342 static void byte_array_put(typeArrayOop obj, StackValue* value, int index, int byte_count) { 1343 switch (byte_count) { 1344 case 1: 1345 obj->byte_at_put(index, (jbyte) value->get_jint()); 1346 break; 1347 case 2: 1348 *((jshort *) check_alignment_get_addr(obj, index, 2)) = (jshort) value->get_jint(); 1349 break; 1350 case 4: 1351 *((jint *) check_alignment_get_addr(obj, index, 4)) = value->get_jint(); 1352 break; 1353 case 8: 1354 *((jlong *) check_alignment_get_addr(obj, index, 8)) = (jlong) value->get_intptr(); 1355 break; 1356 default: 1357 ShouldNotReachHere(); 1358 } 1359 } 1360 #endif // INCLUDE_JVMCI 1361 1362 1363 // restore elements of an eliminated type array 1364 void Deoptimization::reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type) { 1365 int index = 0; 1366 1367 for (int i = 0; i < sv->field_size(); i++) { 1368 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i)); 1369 switch(type) { 1370 case T_LONG: case T_DOUBLE: { 1371 assert(value->type() == T_INT, "Agreement."); 1372 StackValue* low = 1373 StackValue::create_stack_value(fr, reg_map, sv->field_at(++i)); 1374 #ifdef _LP64 1375 jlong res = (jlong)low->get_intptr(); 1376 #else 1377 jlong res = jlong_from(value->get_jint(), low->get_jint()); 1378 #endif 1379 obj->long_at_put(index, res); 1380 break; 1381 } 1382 1383 case T_INT: case T_FLOAT: { // 4 bytes. 1384 assert(value->type() == T_INT, "Agreement."); 1385 bool big_value = false; 1386 if (i + 1 < sv->field_size() && type == T_INT) { 1387 if (sv->field_at(i)->is_location()) { 1388 Location::Type type = ((LocationValue*) sv->field_at(i))->location().type(); 1389 if (type == Location::dbl || type == Location::lng) { 1390 big_value = true; 1391 } 1392 } else if (sv->field_at(i)->is_constant_int()) { 1393 ScopeValue* next_scope_field = sv->field_at(i + 1); 1394 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) { 1395 big_value = true; 1396 } 1397 } 1398 } 1399 1400 if (big_value) { 1401 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++i)); 1402 #ifdef _LP64 1403 jlong res = (jlong)low->get_intptr(); 1404 #else 1405 jlong res = jlong_from(value->get_jint(), low->get_jint()); 1406 #endif 1407 obj->int_at_put(index, *(jint*)&res); 1408 obj->int_at_put(++index, *((jint*)&res + 1)); 1409 } else { 1410 obj->int_at_put(index, value->get_jint()); 1411 } 1412 break; 1413 } 1414 1415 case T_SHORT: 1416 assert(value->type() == T_INT, "Agreement."); 1417 obj->short_at_put(index, (jshort)value->get_jint()); 1418 break; 1419 1420 case T_CHAR: 1421 assert(value->type() == T_INT, "Agreement."); 1422 obj->char_at_put(index, (jchar)value->get_jint()); 1423 break; 1424 1425 case T_BYTE: { 1426 assert(value->type() == T_INT, "Agreement."); 1427 #if INCLUDE_JVMCI 1428 // The value we get is erased as a regular int. We will need to find its actual byte count 'by hand'. 1429 int byte_count = count_number_of_bytes_for_entry(sv, i); 1430 byte_array_put(obj, value, index, byte_count); 1431 // According to byte_count contract, the values from i + 1 to i + byte_count are illegal values. Skip. 1432 i += byte_count - 1; // Balance the loop counter. 1433 index += byte_count; 1434 // index has been updated so continue at top of loop 1435 continue; 1436 #else 1437 obj->byte_at_put(index, (jbyte)value->get_jint()); 1438 break; 1439 #endif // INCLUDE_JVMCI 1440 } 1441 1442 case T_BOOLEAN: { 1443 assert(value->type() == T_INT, "Agreement."); 1444 obj->bool_at_put(index, (jboolean)value->get_jint()); 1445 break; 1446 } 1447 1448 default: 1449 ShouldNotReachHere(); 1450 } 1451 index++; 1452 } 1453 } 1454 1455 // restore fields of an eliminated object array 1456 void Deoptimization::reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj) { 1457 for (int i = 0; i < sv->field_size(); i++) { 1458 StackValue* value = StackValue::create_stack_value(fr, reg_map, sv->field_at(i)); 1459 assert(value->type() == T_OBJECT, "object element expected"); 1460 obj->obj_at_put(i, value->get_obj()()); 1461 } 1462 } 1463 1464 class ReassignedField { 1465 public: 1466 int _offset; 1467 BasicType _type; 1468 public: 1469 ReassignedField() { 1470 _offset = 0; 1471 _type = T_ILLEGAL; 1472 } 1473 }; 1474 1475 // Gets the fields of `klass` that are eliminated by escape analysis and need to be reassigned 1476 static GrowableArray<ReassignedField>* get_reassigned_fields(InstanceKlass* klass, GrowableArray<ReassignedField>* fields, bool is_jvmci) { 1477 InstanceKlass* super = klass->super(); 1478 if (super != nullptr) { 1479 get_reassigned_fields(super, fields, is_jvmci); 1480 } 1481 for (AllFieldStream fs(klass); !fs.done(); fs.next()) { 1482 if (!fs.access_flags().is_static() && (is_jvmci || !fs.field_flags().is_injected())) { 1483 ReassignedField field; 1484 field._offset = fs.offset(); 1485 field._type = Signature::basic_type(fs.signature()); 1486 fields->append(field); 1487 } 1488 } 1489 return fields; 1490 } 1491 1492 // Restore fields of an eliminated instance object employing the same field order used by the compiler. 1493 static int reassign_fields_by_klass(InstanceKlass* klass, frame* fr, RegisterMap* reg_map, ObjectValue* sv, int svIndex, oop obj, bool is_jvmci) { 1494 GrowableArray<ReassignedField>* fields = get_reassigned_fields(klass, new GrowableArray<ReassignedField>(), is_jvmci); 1495 for (int i = 0; i < fields->length(); i++) { 1496 ScopeValue* scope_field = sv->field_at(svIndex); 1497 StackValue* value = StackValue::create_stack_value(fr, reg_map, scope_field); 1498 int offset = fields->at(i)._offset; 1499 BasicType type = fields->at(i)._type; 1500 switch (type) { 1501 case T_OBJECT: case T_ARRAY: 1502 assert(value->type() == T_OBJECT, "Agreement."); 1503 obj->obj_field_put(offset, value->get_obj()()); 1504 break; 1505 1506 case T_INT: case T_FLOAT: { // 4 bytes. 1507 assert(value->type() == T_INT, "Agreement."); 1508 bool big_value = false; 1509 if (i+1 < fields->length() && fields->at(i+1)._type == T_INT) { 1510 if (scope_field->is_location()) { 1511 Location::Type type = ((LocationValue*) scope_field)->location().type(); 1512 if (type == Location::dbl || type == Location::lng) { 1513 big_value = true; 1514 } 1515 } 1516 if (scope_field->is_constant_int()) { 1517 ScopeValue* next_scope_field = sv->field_at(svIndex + 1); 1518 if (next_scope_field->is_constant_long() || next_scope_field->is_constant_double()) { 1519 big_value = true; 1520 } 1521 } 1522 } 1523 1524 if (big_value) { 1525 i++; 1526 assert(i < fields->length(), "second T_INT field needed"); 1527 assert(fields->at(i)._type == T_INT, "T_INT field needed"); 1528 } else { 1529 obj->int_field_put(offset, value->get_jint()); 1530 break; 1531 } 1532 } 1533 /* no break */ 1534 1535 case T_LONG: case T_DOUBLE: { 1536 assert(value->type() == T_INT, "Agreement."); 1537 StackValue* low = StackValue::create_stack_value(fr, reg_map, sv->field_at(++svIndex)); 1538 #ifdef _LP64 1539 jlong res = (jlong)low->get_intptr(); 1540 #else 1541 jlong res = jlong_from(value->get_jint(), low->get_jint()); 1542 #endif 1543 obj->long_field_put(offset, res); 1544 break; 1545 } 1546 1547 case T_SHORT: 1548 assert(value->type() == T_INT, "Agreement."); 1549 obj->short_field_put(offset, (jshort)value->get_jint()); 1550 break; 1551 1552 case T_CHAR: 1553 assert(value->type() == T_INT, "Agreement."); 1554 obj->char_field_put(offset, (jchar)value->get_jint()); 1555 break; 1556 1557 case T_BYTE: 1558 assert(value->type() == T_INT, "Agreement."); 1559 obj->byte_field_put(offset, (jbyte)value->get_jint()); 1560 break; 1561 1562 case T_BOOLEAN: 1563 assert(value->type() == T_INT, "Agreement."); 1564 obj->bool_field_put(offset, (jboolean)value->get_jint()); 1565 break; 1566 1567 default: 1568 ShouldNotReachHere(); 1569 } 1570 svIndex++; 1571 } 1572 return svIndex; 1573 } 1574 1575 // restore fields of all eliminated objects and arrays 1576 void Deoptimization::reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects, bool realloc_failures, bool is_jvmci) { 1577 for (int i = 0; i < objects->length(); i++) { 1578 assert(objects->at(i)->is_object(), "invalid debug information"); 1579 ObjectValue* sv = (ObjectValue*) objects->at(i); 1580 Klass* k = java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()()); 1581 Handle obj = sv->value(); 1582 assert(obj.not_null() || realloc_failures, "reallocation was missed"); 1583 #ifndef PRODUCT 1584 if (PrintDeoptimizationDetails) { 1585 tty->print_cr("reassign fields for object of type %s!", k->name()->as_C_string()); 1586 } 1587 #endif // !PRODUCT 1588 1589 if (obj.is_null()) { 1590 continue; 1591 } 1592 1593 #if INCLUDE_JVMCI 1594 // Don't reassign fields of boxes that came from a cache. Caches may be in CDS. 1595 if (sv->is_auto_box() && ((AutoBoxObjectValue*) sv)->is_cached()) { 1596 continue; 1597 } 1598 #endif // INCLUDE_JVMCI 1599 if (EnableVectorSupport && VectorSupport::is_vector(k)) { 1600 assert(sv->field_size() == 1, "%s not a vector", k->name()->as_C_string()); 1601 ScopeValue* payload = sv->field_at(0); 1602 if (payload->is_location() && 1603 payload->as_LocationValue()->location().type() == Location::vector) { 1604 #ifndef PRODUCT 1605 if (PrintDeoptimizationDetails) { 1606 tty->print_cr("skip field reassignment for this vector - it should be assigned already"); 1607 if (Verbose) { 1608 Handle obj = sv->value(); 1609 k->oop_print_on(obj(), tty); 1610 } 1611 } 1612 #endif // !PRODUCT 1613 continue; // Such vector's value was already restored in VectorSupport::allocate_vector(). 1614 } 1615 // Else fall-through to do assignment for scalar-replaced boxed vector representation 1616 // which could be restored after vector object allocation. 1617 } 1618 if (k->is_instance_klass()) { 1619 InstanceKlass* ik = InstanceKlass::cast(k); 1620 reassign_fields_by_klass(ik, fr, reg_map, sv, 0, obj(), is_jvmci); 1621 } else if (k->is_typeArray_klass()) { 1622 TypeArrayKlass* ak = TypeArrayKlass::cast(k); 1623 reassign_type_array_elements(fr, reg_map, sv, (typeArrayOop) obj(), ak->element_type()); 1624 } else if (k->is_objArray_klass()) { 1625 reassign_object_array_elements(fr, reg_map, sv, (objArrayOop) obj()); 1626 } 1627 } 1628 // These objects may escape when we return to Interpreter after deoptimization. 1629 // We need barrier so that stores that initialize these objects can't be reordered 1630 // with subsequent stores that make these objects accessible by other threads. 1631 OrderAccess::storestore(); 1632 } 1633 1634 1635 // relock objects for which synchronization was eliminated 1636 bool Deoptimization::relock_objects(JavaThread* thread, GrowableArray<MonitorInfo*>* monitors, 1637 JavaThread* deoptee_thread, frame& fr, int exec_mode, bool realloc_failures) { 1638 bool relocked_objects = false; 1639 for (int i = 0; i < monitors->length(); i++) { 1640 MonitorInfo* mon_info = monitors->at(i); 1641 if (mon_info->eliminated()) { 1642 assert(!mon_info->owner_is_scalar_replaced() || realloc_failures, "reallocation was missed"); 1643 relocked_objects = true; 1644 if (!mon_info->owner_is_scalar_replaced()) { 1645 Handle obj(thread, mon_info->owner()); 1646 markWord mark = obj->mark(); 1647 if (exec_mode == Unpack_none) { 1648 if (mark.has_monitor()) { 1649 // defer relocking if the deoptee thread is currently waiting for obj 1650 ObjectMonitor* waiting_monitor = deoptee_thread->current_waiting_monitor(); 1651 if (waiting_monitor != nullptr && waiting_monitor->object() == obj()) { 1652 assert(fr.is_deoptimized_frame(), "frame must be scheduled for deoptimization"); 1653 if (UseObjectMonitorTable) { 1654 mon_info->lock()->clear_object_monitor_cache(); 1655 } 1656 #ifdef ASSERT 1657 else { 1658 assert(!UseObjectMonitorTable, "must be"); 1659 mon_info->lock()->set_bad_metadata_deopt(); 1660 } 1661 #endif 1662 JvmtiDeferredUpdates::inc_relock_count_after_wait(deoptee_thread); 1663 continue; 1664 } 1665 } 1666 } 1667 BasicLock* lock = mon_info->lock(); 1668 // We have lost information about the correct state of the lock stack. 1669 // Entering may create an invalid lock stack. Inflate the lock if it 1670 // was fast_locked to restore the valid lock stack. 1671 if (UseObjectMonitorTable) { 1672 // UseObjectMonitorTable expects the BasicLock cache to be either a 1673 // valid ObjectMonitor* or nullptr. Right now it is garbage, set it 1674 // to nullptr. 1675 lock->clear_object_monitor_cache(); 1676 } 1677 ObjectSynchronizer::enter_for(obj, lock, deoptee_thread); 1678 if (deoptee_thread->lock_stack().contains(obj())) { 1679 LightweightSynchronizer::inflate_fast_locked_object(obj(), ObjectSynchronizer::InflateCause::inflate_cause_vm_internal, 1680 deoptee_thread, thread); 1681 } 1682 assert(mon_info->owner()->is_locked(), "object must be locked now"); 1683 assert(obj->mark().has_monitor(), "must be"); 1684 assert(!deoptee_thread->lock_stack().contains(obj()), "must be"); 1685 assert(ObjectSynchronizer::read_monitor(thread, obj(), obj->mark())->has_owner(deoptee_thread), "must be"); 1686 } 1687 } 1688 } 1689 return relocked_objects; 1690 } 1691 #endif // COMPILER2_OR_JVMCI 1692 1693 vframeArray* Deoptimization::create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures) { 1694 Events::log_deopt_message(thread, "DEOPT PACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(fr.pc()), p2i(fr.sp())); 1695 1696 // Register map for next frame (used for stack crawl). We capture 1697 // the state of the deopt'ing frame's caller. Thus if we need to 1698 // stuff a C2I adapter we can properly fill in the callee-save 1699 // register locations. 1700 frame caller = fr.sender(reg_map); 1701 int frame_size = pointer_delta_as_int(caller.sp(), fr.sp()); 1702 1703 frame sender = caller; 1704 1705 // Since the Java thread being deoptimized will eventually adjust it's own stack, 1706 // the vframeArray containing the unpacking information is allocated in the C heap. 1707 // For Compiler1, the caller of the deoptimized frame is saved for use by unpack_frames(). 1708 vframeArray* array = vframeArray::allocate(thread, frame_size, chunk, reg_map, sender, caller, fr, realloc_failures); 1709 1710 // Compare the vframeArray to the collected vframes 1711 assert(array->structural_compare(thread, chunk), "just checking"); 1712 1713 if (TraceDeoptimization) { 1714 ResourceMark rm; 1715 stringStream st; 1716 st.print_cr("DEOPT PACKING thread=" INTPTR_FORMAT " vframeArray=" INTPTR_FORMAT, p2i(thread), p2i(array)); 1717 st.print(" "); 1718 fr.print_on(&st); 1719 st.print_cr(" Virtual frames (innermost/newest first):"); 1720 for (int index = 0; index < chunk->length(); index++) { 1721 compiledVFrame* vf = chunk->at(index); 1722 int bci = vf->raw_bci(); 1723 const char* code_name; 1724 if (bci == SynchronizationEntryBCI) { 1725 code_name = "sync entry"; 1726 } else { 1727 Bytecodes::Code code = vf->method()->code_at(bci); 1728 code_name = Bytecodes::name(code); 1729 } 1730 1731 st.print(" VFrame %d (" INTPTR_FORMAT ")", index, p2i(vf)); 1732 st.print(" - %s", vf->method()->name_and_sig_as_C_string()); 1733 st.print(" - %s", code_name); 1734 st.print_cr(" @ bci=%d ", bci); 1735 } 1736 tty->print_raw(st.freeze()); 1737 tty->cr(); 1738 } 1739 1740 return array; 1741 } 1742 1743 #if COMPILER2_OR_JVMCI 1744 void Deoptimization::pop_frames_failed_reallocs(JavaThread* thread, vframeArray* array) { 1745 // Reallocation of some scalar replaced objects failed. Record 1746 // that we need to pop all the interpreter frames for the 1747 // deoptimized compiled frame. 1748 assert(thread->frames_to_pop_failed_realloc() == 0, "missed frames to pop?"); 1749 thread->set_frames_to_pop_failed_realloc(array->frames()); 1750 // Unlock all monitors here otherwise the interpreter will see a 1751 // mix of locked and unlocked monitors (because of failed 1752 // reallocations of synchronized objects) and be confused. 1753 for (int i = 0; i < array->frames(); i++) { 1754 MonitorChunk* monitors = array->element(i)->monitors(); 1755 if (monitors != nullptr) { 1756 // Unlock in reverse order starting from most nested monitor. 1757 for (int j = (monitors->number_of_monitors() - 1); j >= 0; j--) { 1758 BasicObjectLock* src = monitors->at(j); 1759 if (src->obj() != nullptr) { 1760 ObjectSynchronizer::exit(src->obj(), src->lock(), thread); 1761 } 1762 } 1763 array->element(i)->free_monitors(); 1764 #ifdef ASSERT 1765 array->element(i)->set_removed_monitors(); 1766 #endif 1767 } 1768 } 1769 } 1770 #endif 1771 1772 void Deoptimization::deoptimize_single_frame(JavaThread* thread, frame fr, Deoptimization::DeoptReason reason) { 1773 assert(fr.can_be_deoptimized(), "checking frame type"); 1774 1775 gather_statistics(reason, Action_none, Bytecodes::_illegal); 1776 1777 if (LogCompilation && xtty != nullptr) { 1778 nmethod* nm = fr.cb()->as_nmethod_or_null(); 1779 assert(nm != nullptr, "only compiled methods can deopt"); 1780 1781 ttyLocker ttyl; 1782 xtty->begin_head("deoptimized thread='%zu' reason='%s' pc='" INTPTR_FORMAT "'",(uintx)thread->osthread()->thread_id(), trap_reason_name(reason), p2i(fr.pc())); 1783 nm->log_identity(xtty); 1784 xtty->end_head(); 1785 for (ScopeDesc* sd = nm->scope_desc_at(fr.pc()); ; sd = sd->sender()) { 1786 xtty->begin_elem("jvms bci='%d'", sd->bci()); 1787 xtty->method(sd->method()); 1788 xtty->end_elem(); 1789 if (sd->is_top()) break; 1790 } 1791 xtty->tail("deoptimized"); 1792 } 1793 1794 Continuation::notify_deopt(thread, fr.sp()); 1795 1796 // Patch the compiled method so that when execution returns to it we will 1797 // deopt the execution state and return to the interpreter. 1798 fr.deoptimize(thread); 1799 } 1800 1801 void Deoptimization::deoptimize(JavaThread* thread, frame fr, DeoptReason reason) { 1802 // Deoptimize only if the frame comes from compile code. 1803 // Do not deoptimize the frame which is already patched 1804 // during the execution of the loops below. 1805 if (!fr.is_compiled_frame() || fr.is_deoptimized_frame()) { 1806 return; 1807 } 1808 ResourceMark rm; 1809 deoptimize_single_frame(thread, fr, reason); 1810 } 1811 1812 #if INCLUDE_JVMCI 1813 address Deoptimization::deoptimize_for_missing_exception_handler(nmethod* nm) { 1814 // there is no exception handler for this pc => deoptimize 1815 nm->make_not_entrant(nmethod::InvalidationReason::MISSING_EXCEPTION_HANDLER); 1816 1817 // Use Deoptimization::deoptimize for all of its side-effects: 1818 // gathering traps statistics, logging... 1819 // it also patches the return pc but we do not care about that 1820 // since we return a continuation to the deopt_blob below. 1821 JavaThread* thread = JavaThread::current(); 1822 RegisterMap reg_map(thread, 1823 RegisterMap::UpdateMap::skip, 1824 RegisterMap::ProcessFrames::include, 1825 RegisterMap::WalkContinuation::skip); 1826 frame runtime_frame = thread->last_frame(); 1827 frame caller_frame = runtime_frame.sender(®_map); 1828 assert(caller_frame.cb()->as_nmethod_or_null() == nm, "expect top frame compiled method"); 1829 vframe* vf = vframe::new_vframe(&caller_frame, ®_map, thread); 1830 compiledVFrame* cvf = compiledVFrame::cast(vf); 1831 ScopeDesc* imm_scope = cvf->scope(); 1832 MethodData* imm_mdo = get_method_data(thread, methodHandle(thread, imm_scope->method()), true); 1833 if (imm_mdo != nullptr) { 1834 // Lock to read ProfileData, and ensure lock is not broken by a safepoint 1835 MutexLocker ml(imm_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag); 1836 1837 ProfileData* pdata = imm_mdo->allocate_bci_to_data(imm_scope->bci(), nullptr); 1838 if (pdata != nullptr && pdata->is_BitData()) { 1839 BitData* bit_data = (BitData*) pdata; 1840 bit_data->set_exception_seen(); 1841 } 1842 } 1843 1844 Deoptimization::deoptimize(thread, caller_frame, Deoptimization::Reason_not_compiled_exception_handler); 1845 1846 MethodData* trap_mdo = get_method_data(thread, methodHandle(thread, nm->method()), true); 1847 if (trap_mdo != nullptr) { 1848 trap_mdo->inc_trap_count(Deoptimization::Reason_not_compiled_exception_handler); 1849 } 1850 1851 return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls(); 1852 } 1853 #endif 1854 1855 void Deoptimization::deoptimize_frame_internal(JavaThread* thread, intptr_t* id, DeoptReason reason) { 1856 assert(thread == Thread::current() || 1857 thread->is_handshake_safe_for(Thread::current()) || 1858 SafepointSynchronize::is_at_safepoint(), 1859 "can only deoptimize other thread at a safepoint/handshake"); 1860 // Compute frame and register map based on thread and sp. 1861 RegisterMap reg_map(thread, 1862 RegisterMap::UpdateMap::skip, 1863 RegisterMap::ProcessFrames::include, 1864 RegisterMap::WalkContinuation::skip); 1865 frame fr = thread->last_frame(); 1866 while (fr.id() != id) { 1867 fr = fr.sender(®_map); 1868 } 1869 deoptimize(thread, fr, reason); 1870 } 1871 1872 1873 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id, DeoptReason reason) { 1874 Thread* current = Thread::current(); 1875 if (thread == current || thread->is_handshake_safe_for(current)) { 1876 Deoptimization::deoptimize_frame_internal(thread, id, reason); 1877 } else { 1878 VM_DeoptimizeFrame deopt(thread, id, reason); 1879 VMThread::execute(&deopt); 1880 } 1881 } 1882 1883 void Deoptimization::deoptimize_frame(JavaThread* thread, intptr_t* id) { 1884 deoptimize_frame(thread, id, Reason_constraint); 1885 } 1886 1887 // JVMTI PopFrame support 1888 JRT_LEAF(void, Deoptimization::popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address)) 1889 { 1890 assert(thread == JavaThread::current(), "pre-condition"); 1891 thread->popframe_preserve_args(in_ByteSize(bytes_to_save), start_address); 1892 } 1893 JRT_END 1894 1895 MethodData* 1896 Deoptimization::get_method_data(JavaThread* thread, const methodHandle& m, 1897 bool create_if_missing) { 1898 JavaThread* THREAD = thread; // For exception macros. 1899 MethodData* mdo = m()->method_data(); 1900 if (mdo == nullptr && create_if_missing && !HAS_PENDING_EXCEPTION) { 1901 // Build an MDO. Ignore errors like OutOfMemory; 1902 // that simply means we won't have an MDO to update. 1903 Method::build_profiling_method_data(m, THREAD); 1904 if (HAS_PENDING_EXCEPTION) { 1905 // Only metaspace OOM is expected. No Java code executed. 1906 assert((PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())), "we expect only an OOM error here"); 1907 CLEAR_PENDING_EXCEPTION; 1908 } 1909 mdo = m()->method_data(); 1910 } 1911 return mdo; 1912 } 1913 1914 #if COMPILER2_OR_JVMCI 1915 void Deoptimization::load_class_by_index(const constantPoolHandle& constant_pool, int index, TRAPS) { 1916 // In case of an unresolved klass entry, load the class. 1917 // This path is exercised from case _ldc in Parse::do_one_bytecode, 1918 // and probably nowhere else. 1919 // Even that case would benefit from simply re-interpreting the 1920 // bytecode, without paying special attention to the class index. 1921 // So this whole "class index" feature should probably be removed. 1922 1923 if (constant_pool->tag_at(index).is_unresolved_klass()) { 1924 Klass* tk = constant_pool->klass_at(index, THREAD); 1925 if (HAS_PENDING_EXCEPTION) { 1926 // Exception happened during classloading. We ignore the exception here, since it 1927 // is going to be rethrown since the current activation is going to be deoptimized and 1928 // the interpreter will re-execute the bytecode. 1929 // Do not clear probable Async Exceptions. 1930 CLEAR_PENDING_NONASYNC_EXCEPTION; 1931 // Class loading called java code which may have caused a stack 1932 // overflow. If the exception was thrown right before the return 1933 // to the runtime the stack is no longer guarded. Reguard the 1934 // stack otherwise if we return to the uncommon trap blob and the 1935 // stack bang causes a stack overflow we crash. 1936 JavaThread* jt = THREAD; 1937 bool guard_pages_enabled = jt->stack_overflow_state()->reguard_stack_if_needed(); 1938 assert(guard_pages_enabled, "stack banging in uncommon trap blob may cause crash"); 1939 } 1940 return; 1941 } 1942 1943 assert(!constant_pool->tag_at(index).is_symbol(), 1944 "no symbolic names here, please"); 1945 } 1946 1947 #if INCLUDE_JFR 1948 1949 class DeoptReasonSerializer : public JfrSerializer { 1950 public: 1951 void serialize(JfrCheckpointWriter& writer) { 1952 writer.write_count((u4)(Deoptimization::Reason_LIMIT + 1)); // + Reason::many (-1) 1953 for (int i = -1; i < Deoptimization::Reason_LIMIT; ++i) { 1954 writer.write_key((u8)i); 1955 writer.write(Deoptimization::trap_reason_name(i)); 1956 } 1957 } 1958 }; 1959 1960 class DeoptActionSerializer : public JfrSerializer { 1961 public: 1962 void serialize(JfrCheckpointWriter& writer) { 1963 static const u4 nof_actions = Deoptimization::Action_LIMIT; 1964 writer.write_count(nof_actions); 1965 for (u4 i = 0; i < Deoptimization::Action_LIMIT; ++i) { 1966 writer.write_key(i); 1967 writer.write(Deoptimization::trap_action_name((int)i)); 1968 } 1969 } 1970 }; 1971 1972 static void register_serializers() { 1973 static int critical_section = 0; 1974 if (1 == critical_section || AtomicAccess::cmpxchg(&critical_section, 0, 1) == 1) { 1975 return; 1976 } 1977 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer()); 1978 JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer()); 1979 } 1980 1981 static void post_deoptimization_event(nmethod* nm, 1982 const Method* method, 1983 int trap_bci, 1984 int instruction, 1985 Deoptimization::DeoptReason reason, 1986 Deoptimization::DeoptAction action) { 1987 assert(nm != nullptr, "invariant"); 1988 assert(method != nullptr, "invariant"); 1989 if (EventDeoptimization::is_enabled()) { 1990 static bool serializers_registered = false; 1991 if (!serializers_registered) { 1992 register_serializers(); 1993 serializers_registered = true; 1994 } 1995 EventDeoptimization event; 1996 event.set_compileId(nm->compile_id()); 1997 event.set_compiler(nm->compiler_type()); 1998 event.set_method(method); 1999 event.set_lineNumber(method->line_number_from_bci(trap_bci)); 2000 event.set_bci(trap_bci); 2001 event.set_instruction(instruction); 2002 event.set_reason(reason); 2003 event.set_action(action); 2004 event.commit(); 2005 } 2006 } 2007 2008 #endif // INCLUDE_JFR 2009 2010 static void log_deopt(nmethod* nm, Method* tm, intptr_t pc, frame& fr, int trap_bci, 2011 const char* reason_name, const char* reason_action) { 2012 LogTarget(Debug, deoptimization) lt; 2013 if (lt.is_enabled()) { 2014 LogStream ls(lt); 2015 bool is_osr = nm->is_osr_method(); 2016 ls.print("cid=%4d %s level=%d", 2017 nm->compile_id(), (is_osr ? "osr" : " "), nm->comp_level()); 2018 ls.print(" %s", tm->name_and_sig_as_C_string()); 2019 ls.print(" trap_bci=%d ", trap_bci); 2020 if (is_osr) { 2021 ls.print("osr_bci=%d ", nm->osr_entry_bci()); 2022 } 2023 ls.print("%s ", reason_name); 2024 ls.print("%s ", reason_action); 2025 ls.print_cr("pc=" INTPTR_FORMAT " relative_pc=" INTPTR_FORMAT, 2026 pc, fr.pc() - nm->code_begin()); 2027 } 2028 } 2029 2030 JRT_ENTRY(void, Deoptimization::uncommon_trap_inner(JavaThread* current, jint trap_request)) { 2031 HandleMark hm(current); 2032 2033 // uncommon_trap() is called at the beginning of the uncommon trap 2034 // handler. Note this fact before we start generating temporary frames 2035 // that can confuse an asynchronous stack walker. This counter is 2036 // decremented at the end of unpack_frames(). 2037 2038 current->inc_in_deopt_handler(); 2039 2040 #if INCLUDE_JVMCI 2041 // JVMCI might need to get an exception from the stack, which in turn requires the register map to be valid 2042 RegisterMap reg_map(current, 2043 RegisterMap::UpdateMap::include, 2044 RegisterMap::ProcessFrames::include, 2045 RegisterMap::WalkContinuation::skip); 2046 #else 2047 RegisterMap reg_map(current, 2048 RegisterMap::UpdateMap::skip, 2049 RegisterMap::ProcessFrames::include, 2050 RegisterMap::WalkContinuation::skip); 2051 #endif 2052 frame stub_frame = current->last_frame(); 2053 frame fr = stub_frame.sender(®_map); 2054 2055 // Log a message 2056 Events::log_deopt_message(current, "Uncommon trap: trap_request=" INT32_FORMAT_X_0 " fr.pc=" INTPTR_FORMAT " relative=" INTPTR_FORMAT, 2057 trap_request, p2i(fr.pc()), fr.pc() - fr.cb()->code_begin()); 2058 2059 { 2060 ResourceMark rm; 2061 2062 DeoptReason reason = trap_request_reason(trap_request); 2063 DeoptAction action = trap_request_action(trap_request); 2064 #if INCLUDE_JVMCI 2065 int debug_id = trap_request_debug_id(trap_request); 2066 #endif 2067 jint unloaded_class_index = trap_request_index(trap_request); // CP idx or -1 2068 2069 vframe* vf = vframe::new_vframe(&fr, ®_map, current); 2070 compiledVFrame* cvf = compiledVFrame::cast(vf); 2071 2072 nmethod* nm = cvf->code(); 2073 2074 ScopeDesc* trap_scope = cvf->scope(); 2075 2076 bool is_receiver_constraint_failure = COMPILER2_PRESENT(VerifyReceiverTypes &&) (reason == Deoptimization::Reason_receiver_constraint); 2077 2078 if (is_receiver_constraint_failure) { 2079 tty->print_cr(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT ", method=%s" JVMCI_ONLY(", debug_id=%d"), 2080 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin(), trap_scope->method()->name_and_sig_as_C_string() 2081 JVMCI_ONLY(COMMA debug_id)); 2082 } 2083 2084 methodHandle trap_method(current, trap_scope->method()); 2085 int trap_bci = trap_scope->bci(); 2086 #if INCLUDE_JVMCI 2087 jlong speculation = current->pending_failed_speculation(); 2088 if (nm->is_compiled_by_jvmci()) { 2089 nm->update_speculation(current); 2090 } else { 2091 assert(speculation == 0, "There should not be a speculation for methods compiled by non-JVMCI compilers"); 2092 } 2093 2094 if (trap_bci == SynchronizationEntryBCI) { 2095 trap_bci = 0; 2096 current->set_pending_monitorenter(true); 2097 } 2098 2099 if (reason == Deoptimization::Reason_transfer_to_interpreter) { 2100 current->set_pending_transfer_to_interpreter(true); 2101 } 2102 #endif 2103 2104 Bytecodes::Code trap_bc = trap_method->java_code_at(trap_bci); 2105 // Record this event in the histogram. 2106 gather_statistics(reason, action, trap_bc); 2107 2108 // Ensure that we can record deopt. history: 2109 bool create_if_missing = ProfileTraps; 2110 2111 methodHandle profiled_method; 2112 #if INCLUDE_JVMCI 2113 if (nm->is_compiled_by_jvmci()) { 2114 profiled_method = methodHandle(current, nm->method()); 2115 } else { 2116 profiled_method = trap_method; 2117 } 2118 #else 2119 profiled_method = trap_method; 2120 #endif 2121 2122 MethodData* trap_mdo = 2123 get_method_data(current, profiled_method, create_if_missing); 2124 2125 { // Log Deoptimization event for JFR, UL and event system 2126 Method* tm = trap_method(); 2127 const char* reason_name = trap_reason_name(reason); 2128 const char* reason_action = trap_action_name(action); 2129 intptr_t pc = p2i(fr.pc()); 2130 2131 JFR_ONLY(post_deoptimization_event(nm, tm, trap_bci, trap_bc, reason, action);) 2132 log_deopt(nm, tm, pc, fr, trap_bci, reason_name, reason_action); 2133 Events::log_deopt_message(current, "Uncommon trap: reason=%s action=%s pc=" INTPTR_FORMAT " method=%s @ %d %s", 2134 reason_name, reason_action, pc, 2135 tm->name_and_sig_as_C_string(), trap_bci, nm->compiler_name()); 2136 } 2137 2138 // Print a bunch of diagnostics, if requested. 2139 if (TraceDeoptimization || LogCompilation || is_receiver_constraint_failure) { 2140 ResourceMark rm; 2141 2142 // Lock to read ProfileData, and ensure lock is not broken by a safepoint 2143 // We must do this already now, since we cannot acquire this lock while 2144 // holding the tty lock (lock ordering by rank). 2145 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag); 2146 2147 ttyLocker ttyl; 2148 2149 char buf[100]; 2150 if (xtty != nullptr) { 2151 xtty->begin_head("uncommon_trap thread='%zu' %s", 2152 os::current_thread_id(), 2153 format_trap_request(buf, sizeof(buf), trap_request)); 2154 #if INCLUDE_JVMCI 2155 if (speculation != 0) { 2156 xtty->print(" speculation='" JLONG_FORMAT "'", speculation); 2157 } 2158 #endif 2159 nm->log_identity(xtty); 2160 } 2161 Symbol* class_name = nullptr; 2162 bool unresolved = false; 2163 if (unloaded_class_index >= 0) { 2164 constantPoolHandle constants (current, trap_method->constants()); 2165 if (constants->tag_at(unloaded_class_index).is_unresolved_klass()) { 2166 class_name = constants->klass_name_at(unloaded_class_index); 2167 unresolved = true; 2168 if (xtty != nullptr) 2169 xtty->print(" unresolved='1'"); 2170 } else if (constants->tag_at(unloaded_class_index).is_symbol()) { 2171 class_name = constants->symbol_at(unloaded_class_index); 2172 } 2173 if (xtty != nullptr) 2174 xtty->name(class_name); 2175 } 2176 if (xtty != nullptr && trap_mdo != nullptr && (int)reason < (int)MethodData::_trap_hist_limit) { 2177 // Dump the relevant MDO state. 2178 // This is the deopt count for the current reason, any previous 2179 // reasons or recompiles seen at this point. 2180 int dcnt = trap_mdo->trap_count(reason); 2181 if (dcnt != 0) 2182 xtty->print(" count='%d'", dcnt); 2183 2184 // We need to lock to read the ProfileData. But to keep the locks ordered, we need to 2185 // lock extra_data_lock before the tty lock. 2186 ProfileData* pdata = trap_mdo->bci_to_data(trap_bci); 2187 int dos = (pdata == nullptr)? 0: pdata->trap_state(); 2188 if (dos != 0) { 2189 xtty->print(" state='%s'", format_trap_state(buf, sizeof(buf), dos)); 2190 if (trap_state_is_recompiled(dos)) { 2191 int recnt2 = trap_mdo->overflow_recompile_count(); 2192 if (recnt2 != 0) 2193 xtty->print(" recompiles2='%d'", recnt2); 2194 } 2195 } 2196 } 2197 if (xtty != nullptr) { 2198 xtty->stamp(); 2199 xtty->end_head(); 2200 } 2201 if (TraceDeoptimization) { // make noise on the tty 2202 stringStream st; 2203 st.print("UNCOMMON TRAP method=%s", trap_scope->method()->name_and_sig_as_C_string()); 2204 st.print(" bci=%d pc=" INTPTR_FORMAT ", relative_pc=" INTPTR_FORMAT JVMCI_ONLY(", debug_id=%d"), 2205 trap_scope->bci(), p2i(fr.pc()), fr.pc() - nm->code_begin() JVMCI_ONLY(COMMA debug_id)); 2206 st.print(" compiler=%s compile_id=%d", nm->compiler_name(), nm->compile_id()); 2207 #if INCLUDE_JVMCI 2208 if (nm->is_compiled_by_jvmci()) { 2209 const char* installed_code_name = nm->jvmci_name(); 2210 if (installed_code_name != nullptr) { 2211 st.print(" (JVMCI: installed code name=%s) ", installed_code_name); 2212 } 2213 } 2214 #endif 2215 st.print(" (@" INTPTR_FORMAT ") thread=%zu reason=%s action=%s unloaded_class_index=%d" JVMCI_ONLY(" debug_id=%d"), 2216 p2i(fr.pc()), 2217 os::current_thread_id(), 2218 trap_reason_name(reason), 2219 trap_action_name(action), 2220 unloaded_class_index 2221 #if INCLUDE_JVMCI 2222 , debug_id 2223 #endif 2224 ); 2225 if (class_name != nullptr) { 2226 st.print(unresolved ? " unresolved class: " : " symbol: "); 2227 class_name->print_symbol_on(&st); 2228 } 2229 st.cr(); 2230 tty->print_raw(st.freeze()); 2231 } 2232 if (xtty != nullptr) { 2233 // Log the precise location of the trap. 2234 for (ScopeDesc* sd = trap_scope; ; sd = sd->sender()) { 2235 xtty->begin_elem("jvms bci='%d'", sd->bci()); 2236 xtty->method(sd->method()); 2237 xtty->end_elem(); 2238 if (sd->is_top()) break; 2239 } 2240 xtty->tail("uncommon_trap"); 2241 } 2242 } 2243 // (End diagnostic printout.) 2244 2245 if (is_receiver_constraint_failure) { 2246 fatal("missing receiver type check"); 2247 } 2248 2249 // Load class if necessary 2250 if (unloaded_class_index >= 0) { 2251 constantPoolHandle constants(current, trap_method->constants()); 2252 load_class_by_index(constants, unloaded_class_index, THREAD); 2253 } 2254 2255 // Flush the nmethod if necessary and desirable. 2256 // 2257 // We need to avoid situations where we are re-flushing the nmethod 2258 // because of a hot deoptimization site. Repeated flushes at the same 2259 // point need to be detected by the compiler and avoided. If the compiler 2260 // cannot avoid them (or has a bug and "refuses" to avoid them), this 2261 // module must take measures to avoid an infinite cycle of recompilation 2262 // and deoptimization. There are several such measures: 2263 // 2264 // 1. If a recompilation is ordered a second time at some site X 2265 // and for the same reason R, the action is adjusted to 'reinterpret', 2266 // to give the interpreter time to exercise the method more thoroughly. 2267 // If this happens, the method's overflow_recompile_count is incremented. 2268 // 2269 // 2. If the compiler fails to reduce the deoptimization rate, then 2270 // the method's overflow_recompile_count will begin to exceed the set 2271 // limit PerBytecodeRecompilationCutoff. If this happens, the action 2272 // is adjusted to 'make_not_compilable', and the method is abandoned 2273 // to the interpreter. This is a performance hit for hot methods, 2274 // but is better than a disastrous infinite cycle of recompilations. 2275 // (Actually, only the method containing the site X is abandoned.) 2276 // 2277 // 3. In parallel with the previous measures, if the total number of 2278 // recompilations of a method exceeds the much larger set limit 2279 // PerMethodRecompilationCutoff, the method is abandoned. 2280 // This should only happen if the method is very large and has 2281 // many "lukewarm" deoptimizations. The code which enforces this 2282 // limit is elsewhere (class nmethod, class Method). 2283 // 2284 // Note that the per-BCI 'is_recompiled' bit gives the compiler one chance 2285 // to recompile at each bytecode independently of the per-BCI cutoff. 2286 // 2287 // The decision to update code is up to the compiler, and is encoded 2288 // in the Action_xxx code. If the compiler requests Action_none 2289 // no trap state is changed, no compiled code is changed, and the 2290 // computation suffers along in the interpreter. 2291 // 2292 // The other action codes specify various tactics for decompilation 2293 // and recompilation. Action_maybe_recompile is the loosest, and 2294 // allows the compiled code to stay around until enough traps are seen, 2295 // and until the compiler gets around to recompiling the trapping method. 2296 // 2297 // The other actions cause immediate removal of the present code. 2298 2299 // Traps caused by injected profile shouldn't pollute trap counts. 2300 bool injected_profile_trap = trap_method->has_injected_profile() && 2301 (reason == Reason_intrinsic || reason == Reason_unreached); 2302 2303 bool update_trap_state = (reason != Reason_tenured) && !injected_profile_trap; 2304 bool make_not_entrant = false; 2305 bool make_not_compilable = false; 2306 bool reprofile = false; 2307 switch (action) { 2308 case Action_none: 2309 // Keep the old code. 2310 update_trap_state = false; 2311 break; 2312 case Action_maybe_recompile: 2313 // Do not need to invalidate the present code, but we can 2314 // initiate another 2315 // Start compiler without (necessarily) invalidating the nmethod. 2316 // The system will tolerate the old code, but new code should be 2317 // generated when possible. 2318 break; 2319 case Action_reinterpret: 2320 // Go back into the interpreter for a while, and then consider 2321 // recompiling form scratch. 2322 make_not_entrant = true; 2323 // Reset invocation counter for outer most method. 2324 // This will allow the interpreter to exercise the bytecodes 2325 // for a while before recompiling. 2326 // By contrast, Action_make_not_entrant is immediate. 2327 // 2328 // Note that the compiler will track null_check, null_assert, 2329 // range_check, and class_check events and log them as if they 2330 // had been traps taken from compiled code. This will update 2331 // the MDO trap history so that the next compilation will 2332 // properly detect hot trap sites. 2333 reprofile = true; 2334 break; 2335 case Action_make_not_entrant: 2336 // Request immediate recompilation, and get rid of the old code. 2337 // Make them not entrant, so next time they are called they get 2338 // recompiled. Unloaded classes are loaded now so recompile before next 2339 // time they are called. Same for uninitialized. The interpreter will 2340 // link the missing class, if any. 2341 make_not_entrant = true; 2342 break; 2343 case Action_make_not_compilable: 2344 // Give up on compiling this method at all. 2345 make_not_entrant = true; 2346 make_not_compilable = true; 2347 break; 2348 default: 2349 ShouldNotReachHere(); 2350 } 2351 2352 #if INCLUDE_JVMCI 2353 // Deoptimization count is used by the CompileBroker to reason about compilations 2354 // it requests so do not pollute the count for deoptimizations in non-default (i.e. 2355 // non-CompilerBroker) compilations. 2356 if (nm->jvmci_skip_profile_deopt()) { 2357 update_trap_state = false; 2358 } 2359 #endif 2360 // Setting +ProfileTraps fixes the following, on all platforms: 2361 // The result is infinite heroic-opt-uncommon-trap/deopt/recompile cycles, since the 2362 // recompile relies on a MethodData* to record heroic opt failures. 2363 2364 // Whether the interpreter is producing MDO data or not, we also need 2365 // to use the MDO to detect hot deoptimization points and control 2366 // aggressive optimization. 2367 bool inc_recompile_count = false; 2368 2369 // Lock to read ProfileData, and ensure lock is not broken by a safepoint 2370 ConditionalMutexLocker ml((trap_mdo != nullptr) ? trap_mdo->extra_data_lock() : nullptr, 2371 (trap_mdo != nullptr), 2372 Mutex::_no_safepoint_check_flag); 2373 ProfileData* pdata = nullptr; 2374 if (ProfileTraps && CompilerConfig::is_c2_or_jvmci_compiler_enabled() && update_trap_state && trap_mdo != nullptr) { 2375 assert(trap_mdo == get_method_data(current, profiled_method, false), "sanity"); 2376 uint this_trap_count = 0; 2377 bool maybe_prior_trap = false; 2378 bool maybe_prior_recompile = false; 2379 2380 pdata = query_update_method_data(trap_mdo, trap_bci, reason, true, 2381 #if INCLUDE_JVMCI 2382 nm->is_compiled_by_jvmci() && nm->is_osr_method(), 2383 #endif 2384 nm->method(), 2385 //outputs: 2386 this_trap_count, 2387 maybe_prior_trap, 2388 maybe_prior_recompile); 2389 // Because the interpreter also counts null, div0, range, and class 2390 // checks, these traps from compiled code are double-counted. 2391 // This is harmless; it just means that the PerXTrapLimit values 2392 // are in effect a little smaller than they look. 2393 2394 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason); 2395 if (per_bc_reason != Reason_none) { 2396 // Now take action based on the partially known per-BCI history. 2397 if (maybe_prior_trap 2398 && this_trap_count >= (uint)PerBytecodeTrapLimit) { 2399 // If there are too many traps at this BCI, force a recompile. 2400 // This will allow the compiler to see the limit overflow, and 2401 // take corrective action, if possible. The compiler generally 2402 // does not use the exact PerBytecodeTrapLimit value, but instead 2403 // changes its tactics if it sees any traps at all. This provides 2404 // a little hysteresis, delaying a recompile until a trap happens 2405 // several times. 2406 // 2407 // Actually, since there is only one bit of counter per BCI, 2408 // the possible per-BCI counts are {0,1,(per-method count)}. 2409 // This produces accurate results if in fact there is only 2410 // one hot trap site, but begins to get fuzzy if there are 2411 // many sites. For example, if there are ten sites each 2412 // trapping two or more times, they each get the blame for 2413 // all of their traps. 2414 make_not_entrant = true; 2415 } 2416 2417 // Detect repeated recompilation at the same BCI, and enforce a limit. 2418 if (make_not_entrant && maybe_prior_recompile) { 2419 // More than one recompile at this point. 2420 inc_recompile_count = maybe_prior_trap; 2421 } 2422 } else { 2423 // For reasons which are not recorded per-bytecode, we simply 2424 // force recompiles unconditionally. 2425 // (Note that PerMethodRecompilationCutoff is enforced elsewhere.) 2426 make_not_entrant = true; 2427 } 2428 2429 // Go back to the compiler if there are too many traps in this method. 2430 if (this_trap_count >= per_method_trap_limit(reason)) { 2431 // If there are too many traps in this method, force a recompile. 2432 // This will allow the compiler to see the limit overflow, and 2433 // take corrective action, if possible. 2434 // (This condition is an unlikely backstop only, because the 2435 // PerBytecodeTrapLimit is more likely to take effect first, 2436 // if it is applicable.) 2437 make_not_entrant = true; 2438 } 2439 2440 // Here's more hysteresis: If there has been a recompile at 2441 // this trap point already, run the method in the interpreter 2442 // for a while to exercise it more thoroughly. 2443 if (make_not_entrant && maybe_prior_recompile && maybe_prior_trap) { 2444 reprofile = true; 2445 } 2446 } 2447 2448 // Take requested actions on the method: 2449 2450 // Recompile 2451 if (make_not_entrant) { 2452 if (!nm->make_not_entrant(nmethod::InvalidationReason::UNCOMMON_TRAP)) { 2453 return; // the call did not change nmethod's state 2454 } 2455 2456 if (pdata != nullptr) { 2457 // Record the recompilation event, if any. 2458 int tstate0 = pdata->trap_state(); 2459 int tstate1 = trap_state_set_recompiled(tstate0, true); 2460 if (tstate1 != tstate0) 2461 pdata->set_trap_state(tstate1); 2462 } 2463 2464 // For code aging we count traps separately here, using make_not_entrant() 2465 // as a guard against simultaneous deopts in multiple threads. 2466 if (reason == Reason_tenured && trap_mdo != nullptr) { 2467 trap_mdo->inc_tenure_traps(); 2468 } 2469 } 2470 if (inc_recompile_count) { 2471 trap_mdo->inc_overflow_recompile_count(); 2472 if ((uint)trap_mdo->overflow_recompile_count() > 2473 (uint)PerBytecodeRecompilationCutoff) { 2474 // Give up on the method containing the bad BCI. 2475 if (trap_method() == nm->method()) { 2476 make_not_compilable = true; 2477 } else { 2478 trap_method->set_not_compilable("overflow_recompile_count > PerBytecodeRecompilationCutoff", CompLevel_full_optimization); 2479 // But give grace to the enclosing nm->method(). 2480 } 2481 } 2482 } 2483 2484 // Reprofile 2485 if (reprofile) { 2486 CompilationPolicy::reprofile(trap_scope, nm->is_osr_method()); 2487 } 2488 2489 // Give up compiling 2490 if (make_not_compilable && !nm->method()->is_not_compilable(CompLevel_full_optimization)) { 2491 assert(make_not_entrant, "consistent"); 2492 nm->method()->set_not_compilable("give up compiling", CompLevel_full_optimization); 2493 } 2494 2495 if (ProfileExceptionHandlers && trap_mdo != nullptr) { 2496 BitData* exception_handler_data = trap_mdo->exception_handler_bci_to_data_or_null(trap_bci); 2497 if (exception_handler_data != nullptr) { 2498 // uncommon trap at the start of an exception handler. 2499 // C2 generates these for un-entered exception handlers. 2500 // mark the handler as entered to avoid generating 2501 // another uncommon trap the next time the handler is compiled 2502 exception_handler_data->set_exception_handler_entered(); 2503 } 2504 } 2505 2506 } // Free marked resources 2507 2508 } 2509 JRT_END 2510 2511 ProfileData* 2512 Deoptimization::query_update_method_data(MethodData* trap_mdo, 2513 int trap_bci, 2514 Deoptimization::DeoptReason reason, 2515 bool update_total_trap_count, 2516 #if INCLUDE_JVMCI 2517 bool is_osr, 2518 #endif 2519 Method* compiled_method, 2520 //outputs: 2521 uint& ret_this_trap_count, 2522 bool& ret_maybe_prior_trap, 2523 bool& ret_maybe_prior_recompile) { 2524 trap_mdo->check_extra_data_locked(); 2525 2526 bool maybe_prior_trap = false; 2527 bool maybe_prior_recompile = false; 2528 uint this_trap_count = 0; 2529 if (update_total_trap_count) { 2530 uint idx = reason; 2531 #if INCLUDE_JVMCI 2532 if (is_osr) { 2533 // Upper half of history array used for traps in OSR compilations 2534 idx += Reason_TRAP_HISTORY_LENGTH; 2535 } 2536 #endif 2537 uint prior_trap_count = trap_mdo->trap_count(idx); 2538 this_trap_count = trap_mdo->inc_trap_count(idx); 2539 2540 // If the runtime cannot find a place to store trap history, 2541 // it is estimated based on the general condition of the method. 2542 // If the method has ever been recompiled, or has ever incurred 2543 // a trap with the present reason , then this BCI is assumed 2544 // (pessimistically) to be the culprit. 2545 maybe_prior_trap = (prior_trap_count != 0); 2546 maybe_prior_recompile = (trap_mdo->decompile_count() != 0); 2547 } 2548 ProfileData* pdata = nullptr; 2549 2550 2551 // For reasons which are recorded per bytecode, we check per-BCI data. 2552 DeoptReason per_bc_reason = reason_recorded_per_bytecode_if_any(reason); 2553 assert(per_bc_reason != Reason_none || update_total_trap_count, "must be"); 2554 if (per_bc_reason != Reason_none) { 2555 // Find the profile data for this BCI. If there isn't one, 2556 // try to allocate one from the MDO's set of spares. 2557 // This will let us detect a repeated trap at this point. 2558 pdata = trap_mdo->allocate_bci_to_data(trap_bci, reason_is_speculate(reason) ? compiled_method : nullptr); 2559 2560 if (pdata != nullptr) { 2561 if (reason_is_speculate(reason) && !pdata->is_SpeculativeTrapData()) { 2562 if (LogCompilation && xtty != nullptr) { 2563 ttyLocker ttyl; 2564 // no more room for speculative traps in this MDO 2565 xtty->elem("speculative_traps_oom"); 2566 } 2567 } 2568 // Query the trap state of this profile datum. 2569 int tstate0 = pdata->trap_state(); 2570 if (!trap_state_has_reason(tstate0, per_bc_reason)) 2571 maybe_prior_trap = false; 2572 if (!trap_state_is_recompiled(tstate0)) 2573 maybe_prior_recompile = false; 2574 2575 // Update the trap state of this profile datum. 2576 int tstate1 = tstate0; 2577 // Record the reason. 2578 tstate1 = trap_state_add_reason(tstate1, per_bc_reason); 2579 // Store the updated state on the MDO, for next time. 2580 if (tstate1 != tstate0) 2581 pdata->set_trap_state(tstate1); 2582 } else { 2583 if (LogCompilation && xtty != nullptr) { 2584 ttyLocker ttyl; 2585 // Missing MDP? Leave a small complaint in the log. 2586 xtty->elem("missing_mdp bci='%d'", trap_bci); 2587 } 2588 } 2589 } 2590 2591 // Return results: 2592 ret_this_trap_count = this_trap_count; 2593 ret_maybe_prior_trap = maybe_prior_trap; 2594 ret_maybe_prior_recompile = maybe_prior_recompile; 2595 return pdata; 2596 } 2597 2598 void 2599 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) { 2600 ResourceMark rm; 2601 // Ignored outputs: 2602 uint ignore_this_trap_count; 2603 bool ignore_maybe_prior_trap; 2604 bool ignore_maybe_prior_recompile; 2605 assert(!reason_is_speculate(reason), "reason speculate only used by compiler"); 2606 // JVMCI uses the total counts to determine if deoptimizations are happening too frequently -> do not adjust total counts 2607 bool update_total_counts = true JVMCI_ONLY( && !UseJVMCICompiler); 2608 2609 // Lock to read ProfileData, and ensure lock is not broken by a safepoint 2610 MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag); 2611 2612 query_update_method_data(trap_mdo, trap_bci, 2613 (DeoptReason)reason, 2614 update_total_counts, 2615 #if INCLUDE_JVMCI 2616 false, 2617 #endif 2618 nullptr, 2619 ignore_this_trap_count, 2620 ignore_maybe_prior_trap, 2621 ignore_maybe_prior_recompile); 2622 } 2623 2624 Deoptimization::UnrollBlock* Deoptimization::uncommon_trap(JavaThread* current, jint trap_request, jint exec_mode) { 2625 // Enable WXWrite: current function is called from methods compiled by C2 directly 2626 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current)); 2627 2628 // Still in Java no safepoints 2629 { 2630 // This enters VM and may safepoint 2631 uncommon_trap_inner(current, trap_request); 2632 } 2633 HandleMark hm(current); 2634 return fetch_unroll_info_helper(current, exec_mode); 2635 } 2636 2637 // Local derived constants. 2638 // Further breakdown of DataLayout::trap_state, as promised by DataLayout. 2639 const int DS_REASON_MASK = ((uint)DataLayout::trap_mask) >> 1; 2640 const int DS_RECOMPILE_BIT = DataLayout::trap_mask - DS_REASON_MASK; 2641 2642 //---------------------------trap_state_reason--------------------------------- 2643 Deoptimization::DeoptReason 2644 Deoptimization::trap_state_reason(int trap_state) { 2645 // This assert provides the link between the width of DataLayout::trap_bits 2646 // and the encoding of "recorded" reasons. It ensures there are enough 2647 // bits to store all needed reasons in the per-BCI MDO profile. 2648 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits"); 2649 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 2650 trap_state -= recompile_bit; 2651 if (trap_state == DS_REASON_MASK) { 2652 return Reason_many; 2653 } else { 2654 assert((int)Reason_none == 0, "state=0 => Reason_none"); 2655 return (DeoptReason)trap_state; 2656 } 2657 } 2658 //-------------------------trap_state_has_reason------------------------------- 2659 int Deoptimization::trap_state_has_reason(int trap_state, int reason) { 2660 assert(reason_is_recorded_per_bytecode((DeoptReason)reason), "valid reason"); 2661 assert(DS_REASON_MASK >= Reason_RECORDED_LIMIT, "enough bits"); 2662 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 2663 trap_state -= recompile_bit; 2664 if (trap_state == DS_REASON_MASK) { 2665 return -1; // true, unspecifically (bottom of state lattice) 2666 } else if (trap_state == reason) { 2667 return 1; // true, definitely 2668 } else if (trap_state == 0) { 2669 return 0; // false, definitely (top of state lattice) 2670 } else { 2671 return 0; // false, definitely 2672 } 2673 } 2674 //-------------------------trap_state_add_reason------------------------------- 2675 int Deoptimization::trap_state_add_reason(int trap_state, int reason) { 2676 assert(reason_is_recorded_per_bytecode((DeoptReason)reason) || reason == Reason_many, "valid reason"); 2677 int recompile_bit = (trap_state & DS_RECOMPILE_BIT); 2678 trap_state -= recompile_bit; 2679 if (trap_state == DS_REASON_MASK) { 2680 return trap_state + recompile_bit; // already at state lattice bottom 2681 } else if (trap_state == reason) { 2682 return trap_state + recompile_bit; // the condition is already true 2683 } else if (trap_state == 0) { 2684 return reason + recompile_bit; // no condition has yet been true 2685 } else { 2686 return DS_REASON_MASK + recompile_bit; // fall to state lattice bottom 2687 } 2688 } 2689 //-----------------------trap_state_is_recompiled------------------------------ 2690 bool Deoptimization::trap_state_is_recompiled(int trap_state) { 2691 return (trap_state & DS_RECOMPILE_BIT) != 0; 2692 } 2693 //-----------------------trap_state_set_recompiled----------------------------- 2694 int Deoptimization::trap_state_set_recompiled(int trap_state, bool z) { 2695 if (z) return trap_state | DS_RECOMPILE_BIT; 2696 else return trap_state & ~DS_RECOMPILE_BIT; 2697 } 2698 //---------------------------format_trap_state--------------------------------- 2699 // This is used for debugging and diagnostics, including LogFile output. 2700 const char* Deoptimization::format_trap_state(char* buf, size_t buflen, 2701 int trap_state) { 2702 assert(buflen > 0, "sanity"); 2703 DeoptReason reason = trap_state_reason(trap_state); 2704 bool recomp_flag = trap_state_is_recompiled(trap_state); 2705 // Re-encode the state from its decoded components. 2706 int decoded_state = 0; 2707 if (reason_is_recorded_per_bytecode(reason) || reason == Reason_many) 2708 decoded_state = trap_state_add_reason(decoded_state, reason); 2709 if (recomp_flag) 2710 decoded_state = trap_state_set_recompiled(decoded_state, recomp_flag); 2711 // If the state re-encodes properly, format it symbolically. 2712 // Because this routine is used for debugging and diagnostics, 2713 // be robust even if the state is a strange value. 2714 size_t len; 2715 if (decoded_state != trap_state) { 2716 // Random buggy state that doesn't decode?? 2717 len = jio_snprintf(buf, buflen, "#%d", trap_state); 2718 } else { 2719 len = jio_snprintf(buf, buflen, "%s%s", 2720 trap_reason_name(reason), 2721 recomp_flag ? " recompiled" : ""); 2722 } 2723 return buf; 2724 } 2725 2726 2727 //--------------------------------statics-------------------------------------- 2728 const char* Deoptimization::_trap_reason_name[] = { 2729 // Note: Keep this in sync. with enum DeoptReason. 2730 "none", 2731 "null_check", 2732 "null_assert" JVMCI_ONLY("_or_unreached0"), 2733 "range_check", 2734 "class_check", 2735 "array_check", 2736 "intrinsic" JVMCI_ONLY("_or_type_checked_inlining"), 2737 "bimorphic" JVMCI_ONLY("_or_optimized_type_check"), 2738 "profile_predicate", 2739 "auto_vectorization_check", 2740 "unloaded", 2741 "uninitialized", 2742 "initialized", 2743 "unreached", 2744 "unhandled", 2745 "constraint", 2746 "div0_check", 2747 "age", 2748 "predicate", 2749 "loop_limit_check", 2750 "speculate_class_check", 2751 "speculate_null_check", 2752 "speculate_null_assert", 2753 "unstable_if", 2754 "unstable_fused_if", 2755 "receiver_constraint", 2756 "short_running_loop" JVMCI_ONLY("_or_aliasing"), 2757 #if INCLUDE_JVMCI 2758 "transfer_to_interpreter", 2759 "not_compiled_exception_handler", 2760 "unresolved", 2761 "jsr_mismatch", 2762 #endif 2763 "tenured" 2764 }; 2765 const char* Deoptimization::_trap_action_name[] = { 2766 // Note: Keep this in sync. with enum DeoptAction. 2767 "none", 2768 "maybe_recompile", 2769 "reinterpret", 2770 "make_not_entrant", 2771 "make_not_compilable" 2772 }; 2773 2774 const char* Deoptimization::trap_reason_name(int reason) { 2775 // Check that every reason has a name 2776 STATIC_ASSERT(sizeof(_trap_reason_name)/sizeof(const char*) == Reason_LIMIT); 2777 2778 if (reason == Reason_many) return "many"; 2779 if ((uint)reason < Reason_LIMIT) 2780 return _trap_reason_name[reason]; 2781 static char buf[20]; 2782 os::snprintf_checked(buf, sizeof(buf), "reason%d", reason); 2783 return buf; 2784 } 2785 const char* Deoptimization::trap_action_name(int action) { 2786 // Check that every action has a name 2787 STATIC_ASSERT(sizeof(_trap_action_name)/sizeof(const char*) == Action_LIMIT); 2788 2789 if ((uint)action < Action_LIMIT) 2790 return _trap_action_name[action]; 2791 static char buf[20]; 2792 os::snprintf_checked(buf, sizeof(buf), "action%d", action); 2793 return buf; 2794 } 2795 2796 // This is used for debugging and diagnostics, including LogFile output. 2797 const char* Deoptimization::format_trap_request(char* buf, size_t buflen, 2798 int trap_request) { 2799 jint unloaded_class_index = trap_request_index(trap_request); 2800 const char* reason = trap_reason_name(trap_request_reason(trap_request)); 2801 const char* action = trap_action_name(trap_request_action(trap_request)); 2802 #if INCLUDE_JVMCI 2803 int debug_id = trap_request_debug_id(trap_request); 2804 #endif 2805 size_t len; 2806 if (unloaded_class_index < 0) { 2807 len = jio_snprintf(buf, buflen, "reason='%s' action='%s'" JVMCI_ONLY(" debug_id='%d'"), 2808 reason, action 2809 #if INCLUDE_JVMCI 2810 ,debug_id 2811 #endif 2812 ); 2813 } else { 2814 len = jio_snprintf(buf, buflen, "reason='%s' action='%s' index='%d'" JVMCI_ONLY(" debug_id='%d'"), 2815 reason, action, unloaded_class_index 2816 #if INCLUDE_JVMCI 2817 ,debug_id 2818 #endif 2819 ); 2820 } 2821 return buf; 2822 } 2823 2824 juint Deoptimization::_deoptimization_hist 2825 [Deoptimization::Reason_LIMIT] 2826 [1 + Deoptimization::Action_LIMIT] 2827 [Deoptimization::BC_CASE_LIMIT] 2828 = {0}; 2829 2830 enum { 2831 LSB_BITS = 8, 2832 LSB_MASK = right_n_bits(LSB_BITS) 2833 }; 2834 2835 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action, 2836 Bytecodes::Code bc) { 2837 assert(reason >= 0 && reason < Reason_LIMIT, "oob"); 2838 assert(action >= 0 && action < Action_LIMIT, "oob"); 2839 _deoptimization_hist[Reason_none][0][0] += 1; // total 2840 _deoptimization_hist[reason][0][0] += 1; // per-reason total 2841 juint* cases = _deoptimization_hist[reason][1+action]; 2842 juint* bc_counter_addr = nullptr; 2843 juint bc_counter = 0; 2844 // Look for an unused counter, or an exact match to this BC. 2845 if (bc != Bytecodes::_illegal) { 2846 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) { 2847 juint* counter_addr = &cases[bc_case]; 2848 juint counter = *counter_addr; 2849 if ((counter == 0 && bc_counter_addr == nullptr) 2850 || (Bytecodes::Code)(counter & LSB_MASK) == bc) { 2851 // this counter is either free or is already devoted to this BC 2852 bc_counter_addr = counter_addr; 2853 bc_counter = counter | bc; 2854 } 2855 } 2856 } 2857 if (bc_counter_addr == nullptr) { 2858 // Overflow, or no given bytecode. 2859 bc_counter_addr = &cases[BC_CASE_LIMIT-1]; 2860 bc_counter = (*bc_counter_addr & ~LSB_MASK); // clear LSB 2861 } 2862 *bc_counter_addr = bc_counter + (1 << LSB_BITS); 2863 } 2864 2865 jint Deoptimization::total_deoptimization_count() { 2866 return _deoptimization_hist[Reason_none][0][0]; 2867 } 2868 2869 // Get the deopt count for a specific reason and a specific action. If either 2870 // one of 'reason' or 'action' is null, the method returns the sum of all 2871 // deoptimizations with the specific 'action' or 'reason' respectively. 2872 // If both arguments are null, the method returns the total deopt count. 2873 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) { 2874 if (reason_str == nullptr && action_str == nullptr) { 2875 return total_deoptimization_count(); 2876 } 2877 juint counter = 0; 2878 for (int reason = 0; reason < Reason_LIMIT; reason++) { 2879 if (reason_str == nullptr || !strcmp(reason_str, trap_reason_name(reason))) { 2880 for (int action = 0; action < Action_LIMIT; action++) { 2881 if (action_str == nullptr || !strcmp(action_str, trap_action_name(action))) { 2882 juint* cases = _deoptimization_hist[reason][1+action]; 2883 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) { 2884 counter += cases[bc_case] >> LSB_BITS; 2885 } 2886 } 2887 } 2888 } 2889 } 2890 return counter; 2891 } 2892 2893 void Deoptimization::print_statistics() { 2894 juint total = total_deoptimization_count(); 2895 juint account = total; 2896 if (total != 0) { 2897 ttyLocker ttyl; 2898 if (xtty != nullptr) xtty->head("statistics type='deoptimization'"); 2899 tty->print_cr("Deoptimization traps recorded:"); 2900 #define PRINT_STAT_LINE(name, r) \ 2901 tty->print_cr(" %4d (%4.1f%%) %s", (int)(r), ((r) * 100.0) / total, name); 2902 PRINT_STAT_LINE("total", total); 2903 // For each non-zero entry in the histogram, print the reason, 2904 // the action, and (if specifically known) the type of bytecode. 2905 for (int reason = 0; reason < Reason_LIMIT; reason++) { 2906 for (int action = 0; action < Action_LIMIT; action++) { 2907 juint* cases = _deoptimization_hist[reason][1+action]; 2908 for (int bc_case = 0; bc_case < BC_CASE_LIMIT; bc_case++) { 2909 juint counter = cases[bc_case]; 2910 if (counter != 0) { 2911 char name[1*K]; 2912 Bytecodes::Code bc = (Bytecodes::Code)(counter & LSB_MASK); 2913 os::snprintf_checked(name, sizeof(name), "%s/%s/%s", 2914 trap_reason_name(reason), 2915 trap_action_name(action), 2916 Bytecodes::is_defined(bc)? Bytecodes::name(bc): "other"); 2917 juint r = counter >> LSB_BITS; 2918 tty->print_cr(" %40s: " UINT32_FORMAT " (%.1f%%)", name, r, (r * 100.0) / total); 2919 account -= r; 2920 } 2921 } 2922 } 2923 } 2924 if (account != 0) { 2925 PRINT_STAT_LINE("unaccounted", account); 2926 } 2927 #undef PRINT_STAT_LINE 2928 if (xtty != nullptr) xtty->tail("statistics"); 2929 } 2930 } 2931 2932 #else // COMPILER2_OR_JVMCI 2933 2934 2935 // Stubs for C1 only system. 2936 bool Deoptimization::trap_state_is_recompiled(int trap_state) { 2937 return false; 2938 } 2939 2940 const char* Deoptimization::trap_reason_name(int reason) { 2941 return "unknown"; 2942 } 2943 2944 jint Deoptimization::total_deoptimization_count() { 2945 return 0; 2946 } 2947 2948 jint Deoptimization::deoptimization_count(const char *reason_str, const char *action_str) { 2949 return 0; 2950 } 2951 2952 void Deoptimization::print_statistics() { 2953 // no output 2954 } 2955 2956 void 2957 Deoptimization::update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason) { 2958 // no update 2959 } 2960 2961 int Deoptimization::trap_state_has_reason(int trap_state, int reason) { 2962 return 0; 2963 } 2964 2965 void Deoptimization::gather_statistics(DeoptReason reason, DeoptAction action, 2966 Bytecodes::Code bc) { 2967 // no update 2968 } 2969 2970 const char* Deoptimization::format_trap_state(char* buf, size_t buflen, 2971 int trap_state) { 2972 jio_snprintf(buf, buflen, "#%d", trap_state); 2973 return buf; 2974 } 2975 2976 #endif // COMPILER2_OR_JVMCI