1 /*
  2  * Copyright (c) 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 "cds/cdsConfig.hpp"
 26 #include "ci/ciEnv.hpp"
 27 #include "ci/ciMetadata.hpp"
 28 #include "classfile/compactHashtable.hpp"
 29 #include "classfile/javaClasses.hpp"
 30 #include "classfile/symbolTable.hpp"
 31 #include "classfile/systemDictionaryShared.hpp"
 32 #include "compiler/compileTask.hpp"
 33 #include "memory/metadataFactory.hpp"
 34 #include "memory/metaspaceClosure.hpp"
 35 #include "memory/resourceArea.hpp"
 36 #include "memory/universe.hpp"
 37 #include "oops/method.hpp"
 38 #include "oops/method.inline.hpp"
 39 #include "oops/methodCounters.hpp"
 40 #include "oops/recompilationSchedule.hpp"
 41 #include "oops/trainingData.hpp"
 42 #include "runtime/arguments.hpp"
 43 #include "runtime/javaThread.inline.hpp"
 44 #include "runtime/jniHandles.inline.hpp"
 45 #include "utilities/growableArray.hpp"
 46 
 47 TrainingData::TrainingDataSet TrainingData::_training_data_set(1024, 0x3fffffff);
 48 TrainingData::TrainingDataDictionary TrainingData::_archived_training_data_dictionary;
 49 TrainingData::TrainingDataDictionary TrainingData::_archived_training_data_dictionary_for_dumping;
 50 TrainingData::DumptimeTrainingDataDictionary* TrainingData::_dumptime_training_data_dictionary = nullptr;
 51 int TrainingData::TrainingDataLocker::_lock_mode;
 52 volatile bool TrainingData::TrainingDataLocker::_snapshot = false;
 53 
 54 MethodTrainingData::MethodTrainingData() {
 55   // Used by cppVtables.cpp only
 56   assert(CDSConfig::is_dumping_static_archive() || UseSharedSpaces, "only for CDS");
 57 }
 58 
 59 KlassTrainingData::KlassTrainingData() {
 60   // Used by cppVtables.cpp only
 61   assert(CDSConfig::is_dumping_static_archive() || UseSharedSpaces, "only for CDS");
 62 }
 63 
 64 CompileTrainingData::CompileTrainingData() : _level(-1), _compile_id(-1) {
 65   // Used by cppVtables.cpp only
 66   assert(CDSConfig::is_dumping_static_archive() || UseSharedSpaces, "only for CDS");
 67 }
 68 
 69 void TrainingData::initialize() {
 70   // this is a nop if training modes are not enabled
 71   if (have_data() || need_data()) {
 72     TrainingDataLocker::initialize();
 73   }
 74   RecompilationSchedule::initialize();
 75   if (have_data() && need_data()) {
 76     TrainingDataLocker l;
 77     archived_training_data_dictionary()->iterate_all([&](TrainingData* td) {
 78       training_data_set()->install(td);
 79     });
 80   }
 81 }
 82 
 83 static void verify_archived_entry(TrainingData* td, const TrainingData::Key* k) {
 84   guarantee(TrainingData::Key::can_compute_cds_hash(k), "");
 85   TrainingData* td1 = TrainingData::lookup_archived_training_data(k);
 86   guarantee(td == td1, "");
 87 }
 88 
 89 void TrainingData::verify() {
 90   if (have_data() && !need_data() && !assembling_data()) {
 91     archived_training_data_dictionary()->iterate_all([&](TrainingData* td) {
 92       if (td->is_KlassTrainingData()) {
 93         KlassTrainingData* ktd = td->as_KlassTrainingData();
 94         if (ktd->has_holder() && ktd->holder()->is_loaded()) {
 95           Key k(ktd->holder());
 96           verify_archived_entry(td, &k);
 97         }
 98         ktd->verify();
 99       } else if (td->is_MethodTrainingData()) {
100         MethodTrainingData* mtd = td->as_MethodTrainingData();
101         if (mtd->has_holder() && mtd->holder()->method_holder()->is_loaded()) {
102           Key k(mtd->holder());
103           verify_archived_entry(td, &k);
104         }
105         mtd->verify(/*verify_dep_counter*/true);
106       }
107     });
108   }
109   if (need_data()) {
110     TrainingDataLocker l;
111     training_data_set()->iterate([&](TrainingData* td) {
112       if (td->is_KlassTrainingData()) {
113         KlassTrainingData* ktd = td->as_KlassTrainingData();
114         ktd->verify();
115       } else if (td->is_MethodTrainingData()) {
116         MethodTrainingData* mtd = td->as_MethodTrainingData();
117         // During the training run init deps tracking is not setup yet,
118         // don't verify it.
119         mtd->verify(/*verify_dep_counter*/false);
120       }
121     });
122   }
123 }
124 
125 MethodTrainingData* MethodTrainingData::make(const methodHandle& method, bool null_if_not_found, bool use_cache) {
126   MethodTrainingData* mtd = nullptr;
127   if (!have_data() && !need_data()) {
128     return mtd;
129   }
130   // Try grabbing the cached value first.
131   // Cache value is stored in MethodCounters and the following are the
132   // possible states:
133   // 1. Cached value is method_training_data_sentinel().
134   //    This is an initial state and needs a full lookup.
135   // 2. Cached value is null.
136   //    Lookup failed the last time, if we don't plan to create a new TD object,
137   //    i.e. null_if_no_found == true, then just return a null.
138   // 3. Cache value is not null.
139   //    Return it, the value of training_data_lookup_failed doesn't matter.
140   MethodCounters* mcs = method->method_counters();
141   if (mcs != nullptr) {
142     mtd = mcs->method_training_data();
143     if (mtd != nullptr && mtd != mcs->method_training_data_sentinel()) {
144       return mtd;
145     }
146     if (null_if_not_found && mtd == nullptr) {
147       assert(mtd == nullptr, "No training data found");
148       return nullptr;
149     }
150   } else if (use_cache) {
151     mcs = Method::build_method_counters(Thread::current(), method());
152   }
153 
154   TrainingData* td = nullptr;
155 
156   Key key(method());
157   if (have_data() && !need_data()) {
158     td = lookup_archived_training_data(&key);
159     if (td != nullptr) {
160       mtd = td->as_MethodTrainingData();
161     } else {
162       mtd = nullptr;
163     }
164     // Cache the pointer to MTD in MethodCounters for faster lookup (could be null if not found)
165     method->init_training_data(mtd);
166   }
167 
168   if (need_data()) {
169     TrainingDataLocker l;
170     td = training_data_set()->find(&key);
171     if (td == nullptr) {
172       if (!null_if_not_found) {
173         KlassTrainingData* ktd = KlassTrainingData::make(method->method_holder());
174         if (ktd == nullptr) {
175           return nullptr; // allocation failure
176         }
177         mtd = MethodTrainingData::allocate(method(), ktd);
178         if (mtd == nullptr) {
179           return nullptr; // allocation failure
180         }
181         td = training_data_set()->install(mtd);
182         assert(td == mtd, "");
183       } else {
184         mtd = nullptr;
185       }
186     } else {
187       mtd = td->as_MethodTrainingData();
188     }
189     // Cache the pointer to MTD in MethodCounters for faster lookup (could be null if not found)
190     method->init_training_data(mtd);
191   }
192 
193   return mtd;
194 }
195 
196 void MethodTrainingData::print_on(outputStream* st, bool name_only) const {
197   if (has_holder()) {
198     _klass->print_on(st, true);
199     st->print(".");
200     name()->print_symbol_on(st);
201     signature()->print_symbol_on(st);
202   }
203   if (name_only) {
204     return;
205   }
206   if (!has_holder()) {
207     st->print("[SYM]");
208   }
209   if (_level_mask) {
210     st->print(" LM%d", _level_mask);
211   }
212   st->print(" mc=%p mdo=%p", _final_counters, _final_profile);
213 }
214 
215 CompileTrainingData* CompileTrainingData::make(CompileTask* task) {
216   int level = task->comp_level();
217   int compile_id = task->compile_id();
218   Thread* thread = Thread::current();
219   methodHandle m(thread, task->method());
220   if (m->method_holder() == nullptr) {
221     return nullptr; // do not record (dynamically generated method)
222   }
223   MethodTrainingData* mtd = MethodTrainingData::make(m);
224   if (mtd == nullptr) {
225     return nullptr; // allocation failure
226   }
227   mtd->notice_compilation(level);
228 
229   TrainingDataLocker l;
230   CompileTrainingData* ctd = CompileTrainingData::allocate(mtd, level, compile_id);
231   if (ctd != nullptr) {
232     CompileTrainingData*& last_ctd = mtd->_last_toplevel_compiles[level - 1];
233     if (last_ctd != nullptr) {
234       assert(mtd->highest_top_level() >= level, "consistency");
235       if (last_ctd->compile_id() < compile_id) {
236         last_ctd->clear_init_deps();
237         last_ctd = ctd;
238       }
239     } else {
240       last_ctd = ctd;
241       mtd->notice_toplevel_compilation(level);
242     }
243   }
244   return ctd;
245 }
246 
247 
248 void CompileTrainingData::dec_init_deps_left_release(KlassTrainingData* ktd) {
249   LogStreamHandle(Trace, training) log;
250   if (log.is_enabled()) {
251     log.print("CTD "); print_on(&log); log.cr();
252     log.print("KTD "); ktd->print_on(&log); log.cr();
253   }
254   assert(ktd!= nullptr && ktd->has_holder(), "");
255   assert(_init_deps.contains(ktd), "");
256   assert(_init_deps_left > 0, "");
257 
258   uint init_deps_left1 = AtomicAccess::sub(&_init_deps_left, 1);
259 
260   if (log.is_enabled()) {
261     uint init_deps_left2 = compute_init_deps_left();
262     log.print("init_deps_left: %d (%d)", init_deps_left1, init_deps_left2);
263     ktd->print_on(&log, true);
264   }
265 }
266 
267 uint CompileTrainingData::compute_init_deps_left(bool count_initialized) {
268   int left = 0;
269   for (int i = 0; i < _init_deps.length(); i++) {
270     KlassTrainingData* ktd = _init_deps.at(i);
271     // Ignore symbolic refs and already initialized classes (unless explicitly requested).
272     if (ktd->has_holder()) {
273       InstanceKlass* holder = ktd->holder();
274       if (!ktd->holder()->is_initialized() || count_initialized) {
275         ++left;
276       } else if (holder->defined_by_other_loaders()) {
277         Key k(holder);
278         if (CDS_ONLY(!Key::can_compute_cds_hash(&k)) NOT_CDS(true)) {
279           ++left;
280         }
281       }
282     }
283   }
284   return left;
285 }
286 
287 void CompileTrainingData::print_on(outputStream* st, bool name_only) const {
288   _method->print_on(st, true);
289   st->print("#%dL%d", _compile_id, _level);
290   if (name_only) {
291     return;
292   }
293   if (_init_deps.length() > 0) {
294     if (_init_deps_left > 0) {
295       st->print(" udeps=%d", _init_deps_left);
296     }
297     for (int i = 0, len = _init_deps.length(); i < len; i++) {
298       st->print(" dep:");
299       _init_deps.at(i)->print_on(st, true);
300     }
301   }
302 }
303 
304 void CompileTrainingData::notice_inlined_method(CompileTask* task,
305                                                 const methodHandle& method) {
306   MethodTrainingData* mtd = MethodTrainingData::make(method);
307   if (mtd != nullptr) {
308     mtd->notice_compilation(task->comp_level(), true);
309   }
310 }
311 
312 void CompileTrainingData::notice_jit_observation(ciEnv* env, ciBaseObject* what) {
313   // A JIT is starting to look at class k.
314   // We could follow the queries that it is making, but it is
315   // simpler to assume, conservatively, that the JIT will
316   // eventually depend on the initialization state of k.
317   ciMetadata* md = nullptr;
318   if (what->is_object()) {
319     md = what->as_object()->klass();
320   } else if (what->is_metadata()) {
321     md = what->as_metadata();
322   }
323   if (md != nullptr && md->is_loaded() && md->is_instance_klass()) {
324     ciInstanceKlass* cik = md->as_instance_klass();
325     if (!cik->is_initialized()) {
326       return;
327     }
328     KlassTrainingData* ktd = KlassTrainingData::make(cik->get_instanceKlass());
329     if (ktd == nullptr) {
330       // Allocation failure or snapshot in progress
331       return;
332     }
333     // This JIT task is (probably) requesting that ik be initialized,
334     // so add it to my _init_deps list.
335     TrainingDataLocker l;
336     if (l.can_add()) {
337       add_init_dep(ktd);
338     }
339   }
340 }
341 
342 void KlassTrainingData::prepare(Visitor& visitor) {
343   if (visitor.is_visited(this)) {
344     return;
345   }
346   visitor.visit(this);
347   _comp_deps.prepare();
348 }
349 
350 void MethodTrainingData::prepare(Visitor& visitor) {
351   if (visitor.is_visited(this)) {
352     return;
353   }
354   visitor.visit(this);
355   klass()->prepare(visitor);
356   if (has_holder()) {
357     _final_counters = holder()->method_counters();
358     _final_profile  = holder()->method_data();
359     assert(_final_profile == nullptr || _final_profile->method() == holder(), "");
360     _invocation_count = holder()->invocation_count();
361     _backedge_count = holder()->backedge_count();
362   }
363   for (int i = 0; i < CompLevel_count - 1; i++) {
364     CompileTrainingData* ctd = _last_toplevel_compiles[i];
365     if (ctd != nullptr) {
366       ctd->prepare(visitor);
367     }
368   }
369 }
370 
371 void CompileTrainingData::prepare(Visitor& visitor) {
372   if (visitor.is_visited(this)) {
373     return;
374   }
375   visitor.visit(this);
376   method()->prepare(visitor);
377   _init_deps.prepare();
378   _ci_records.prepare();
379 }
380 
381 KlassTrainingData* KlassTrainingData::make(InstanceKlass* holder, bool null_if_not_found) {
382   Key key(holder);
383   TrainingData* td = CDS_ONLY((have_data() && !need_data()) ? lookup_archived_training_data(&key) :) nullptr;
384   KlassTrainingData* ktd = nullptr;
385   if (td != nullptr) {
386     ktd = td->as_KlassTrainingData();
387     guarantee(!ktd->has_holder() || ktd->holder() == holder, "");
388     if (ktd->has_holder()) {
389       return ktd;
390     } else {
391       ktd = nullptr;
392     }
393   }
394   if (need_data()) {
395     TrainingDataLocker l;
396     td = training_data_set()->find(&key);
397     if (td == nullptr) {
398       if (null_if_not_found) {
399         return nullptr;
400       }
401       ktd = KlassTrainingData::allocate(holder);
402       if (ktd == nullptr) {
403         return nullptr; // allocation failure
404       }
405       td = training_data_set()->install(ktd);
406       assert(ktd == td, "");
407     } else {
408       ktd = td->as_KlassTrainingData();
409       guarantee(ktd->holder() != nullptr, "null holder");
410     }
411     assert(ktd != nullptr, "");
412     guarantee(ktd->holder() == holder, "");
413   }
414   return ktd;
415 }
416 
417 void KlassTrainingData::print_on(outputStream* st, bool name_only) const {
418   if (has_holder()) {
419     name()->print_symbol_on(st);
420     switch (holder()->init_state()) {
421       case InstanceKlass::allocated:            st->print("[A]"); break;
422       case InstanceKlass::loaded:               st->print("[D]"); break;
423       case InstanceKlass::linked:               st->print("[L]"); break;
424       case InstanceKlass::being_initialized:    st->print("[i]"); break;
425       case InstanceKlass::fully_initialized:                      break;
426       case InstanceKlass::initialization_error: st->print("[E]"); break;
427       default: fatal("unknown state: %d", holder()->init_state());
428     }
429     if (holder()->is_interface()) {
430       st->print("I");
431     }
432   } else {
433     st->print("[SYM]");
434   }
435   if (name_only) {
436     return;
437   }
438   if (_comp_deps.length() > 0) {
439     for (int i = 0, len = _comp_deps.length(); i < len; i++) {
440       st->print(" dep:");
441       _comp_deps.at(i)->print_on(st, true);
442     }
443   }
444 }
445 
446 KlassTrainingData::KlassTrainingData(InstanceKlass* klass) : TrainingData(klass) {
447   assert(klass != nullptr, "");
448   // The OopHandle constructor will allocate a handle. We don't need to ever release it so we don't preserve
449   // the handle object.
450   OopHandle handle(Universe::vm_global(), klass->java_mirror());
451   _holder = klass;
452   assert(holder() == klass, "");
453 }
454 
455 void KlassTrainingData::notice_fully_initialized() {
456   ResourceMark rm;
457   assert(has_holder(), "");
458   assert(holder()->is_initialized(), "wrong state: %s %s",
459          holder()->name()->as_C_string(), holder()->init_state_name());
460 
461   TrainingDataLocker l; // Not a real lock if we don't collect the data,
462                         // that's why we need the atomic decrement below.
463   for (int i = 0; i < comp_dep_count(); i++) {
464     comp_dep(i)->dec_init_deps_left_release(this);
465   }
466   holder()->set_has_init_deps_processed();
467 }
468 
469 void TrainingData::init_dumptime_table(TRAPS) {
470   if (assembling_data() && !need_data()) {
471     _dumptime_training_data_dictionary = new DumptimeTrainingDataDictionary();
472     _archived_training_data_dictionary.iterate_all([&](TrainingData* record) {
473       _dumptime_training_data_dictionary->append(record);
474     });
475   }
476   if (need_data()) {
477     _dumptime_training_data_dictionary = new DumptimeTrainingDataDictionary();
478     TrainingDataLocker l;
479     TrainingDataLocker::snapshot();
480     ResourceMark rm;
481     Visitor visitor(training_data_set()->size());
482     training_data_set()->iterate([&](TrainingData* td) {
483       td->prepare(visitor);
484       if (!td->is_CompileTrainingData()) {
485         _dumptime_training_data_dictionary->append(td);
486       }
487     });
488   }
489 
490   RecompilationSchedule::prepare(CHECK);
491 
492   if (AOTVerifyTrainingData) {
493     TrainingData::verify();
494   }
495 }
496 
497 void TrainingData::iterate_roots(MetaspaceClosure* it) {
498   if (_dumptime_training_data_dictionary != nullptr) {
499     for (int i = 0; i < _dumptime_training_data_dictionary->length(); i++) {
500       _dumptime_training_data_dictionary->at(i).metaspace_pointers_do(it);
501     }
502   }
503   RecompilationSchedule::iterate_roots(it);
504 }
505 
506 void TrainingData::dump_training_data() {
507   if (_dumptime_training_data_dictionary != nullptr) {
508     CompactHashtableStats stats;
509     _archived_training_data_dictionary_for_dumping.reset();
510     CompactHashtableWriter writer(_dumptime_training_data_dictionary->length(), &stats);
511     for (int i = 0; i < _dumptime_training_data_dictionary->length(); i++) {
512       TrainingData* td = _dumptime_training_data_dictionary->at(i).training_data();
513 #ifdef ASSERT
514       for (int j = i+1; j < _dumptime_training_data_dictionary->length(); j++) {
515         TrainingData* td1 = _dumptime_training_data_dictionary->at(j).training_data();
516         assert(!TrainingData::Key::equals(td1, td->key(), -1), "conflict");
517       }
518 #endif // ASSERT
519       td = ArchiveBuilder::current()->get_buffered_addr(td);
520       uint hash = TrainingData::Key::cds_hash(td->key());
521       u4 delta = ArchiveBuilder::current()->buffer_to_offset_u4((address)td);
522       writer.add(hash, delta);
523     }
524     writer.dump(&_archived_training_data_dictionary_for_dumping, "training data dictionary");
525   }
526 }
527 
528 void TrainingData::cleanup_training_data() {
529   if (_dumptime_training_data_dictionary != nullptr) {
530     ResourceMark rm;
531     Visitor visitor(_dumptime_training_data_dictionary->length());
532     for (int i = 0; i < _dumptime_training_data_dictionary->length(); i++) {
533       TrainingData* td = _dumptime_training_data_dictionary->at(i).training_data();
534       td->cleanup(visitor);
535     }
536     // Throw away all elements with empty keys
537     int j = 0;
538     for (int i = 0; i < _dumptime_training_data_dictionary->length(); i++) {
539       TrainingData* td = _dumptime_training_data_dictionary->at(i).training_data();
540       if (td->key()->is_empty()) {
541         continue;
542       }
543       if (i != j) { // no need to copy if it's the same
544         _dumptime_training_data_dictionary->at_put(j, td);
545       }
546       j++;
547     }
548     _dumptime_training_data_dictionary->trunc_to(j);
549   }
550   RecompilationSchedule::cleanup();
551 }
552 
553 void KlassTrainingData::cleanup(Visitor& visitor) {
554   if (visitor.is_visited(this)) {
555     return;
556   }
557   visitor.visit(this);
558   if (has_holder()) {
559     bool is_excluded = !holder()->is_loaded();
560     if (CDSConfig::is_at_aot_safepoint()) {
561       // Check for AOT exclusion only at AOT safe point.
562       is_excluded |= SystemDictionaryShared::should_be_excluded(holder());
563     }
564     if (is_excluded) {
565       ResourceMark rm;
566       log_debug(aot, training)("Cleanup KTD %s", name()->as_klass_external_name());
567       _holder = nullptr;
568       key()->make_empty();
569     }
570   }
571   for (int i = 0; i < _comp_deps.length(); i++) {
572     _comp_deps.at(i)->cleanup(visitor);
573   }
574 }
575 
576 void MethodTrainingData::cleanup(Visitor& visitor) {
577   if (visitor.is_visited(this)) {
578     return;
579   }
580   visitor.visit(this);
581   if (has_holder()) {
582     if (CDSConfig::is_at_aot_safepoint() && SystemDictionaryShared::should_be_excluded(holder()->method_holder())) {
583       // Check for AOT exclusion only at AOT safe point.
584       log_debug(aot, training)("Cleanup MTD %s::%s", name()->as_klass_external_name(), signature()->as_utf8());
585       if (_final_profile != nullptr && _final_profile->method() != _holder) {
586         log_warning(aot, training)("Stale MDO for  %s::%s", name()->as_klass_external_name(), signature()->as_utf8());
587       }
588       _final_profile = nullptr;
589       _final_counters = nullptr;
590       _holder = nullptr;
591       key()->make_empty();
592     }
593   }
594   for (int i = 0; i < CompLevel_count - 1; i++) {
595     CompileTrainingData* ctd = _last_toplevel_compiles[i];
596     if (ctd != nullptr) {
597       ctd->cleanup(visitor);
598     }
599   }
600 }
601 
602 void KlassTrainingData::verify() {
603   for (int i = 0; i < comp_dep_count(); i++) {
604     CompileTrainingData* ctd = comp_dep(i);
605     if (!ctd->_init_deps.contains(this)) {
606       print_on(tty); tty->cr();
607       ctd->print_on(tty); tty->cr();
608     }
609     guarantee(ctd->_init_deps.contains(this), "");
610   }
611 }
612 
613 void MethodTrainingData::verify(bool verify_dep_counter) {
614   iterate_compiles([&](CompileTrainingData* ctd) {
615     ctd->verify(verify_dep_counter);
616   });
617 }
618 
619 void CompileTrainingData::verify(bool verify_dep_counter) {
620   for (int i = 0; i < init_dep_count(); i++) {
621     KlassTrainingData* ktd = init_dep(i);
622     if (ktd->has_holder() && ktd->holder()->defined_by_other_loaders()) {
623       LogStreamHandle(Info, training) log;
624       if (log.is_enabled()) {
625         ResourceMark rm;
626         log.print("CTD "); print_value_on(&log);
627         log.print(" depends on unregistered class %s", ktd->holder()->name()->as_C_string());
628       }
629     }
630     if (!ktd->_comp_deps.contains(this)) {
631       print_on(tty); tty->cr();
632       ktd->print_on(tty); tty->cr();
633     }
634     guarantee(ktd->_comp_deps.contains(this), "");
635   }
636 
637   if (verify_dep_counter) {
638     int init_deps_left1 = init_deps_left_acquire();
639     int init_deps_left2 = compute_init_deps_left();
640 
641     bool invariant = (init_deps_left1 >= init_deps_left2);
642     if (!invariant) {
643       print_on(tty);
644       tty->cr();
645     }
646     guarantee(invariant, "init deps invariant violation: %d >= %d", init_deps_left1, init_deps_left2);
647   }
648 }
649 
650 void CompileTrainingData::cleanup(Visitor& visitor) {
651   if (visitor.is_visited(this)) {
652     return;
653   }
654   visitor.visit(this);
655   method()->cleanup(visitor);
656 }
657 
658 void TrainingData::serialize(SerializeClosure* soc) {
659   if (soc->writing()) {
660     _archived_training_data_dictionary_for_dumping.serialize_header(soc);
661   } else {
662     _archived_training_data_dictionary.serialize_header(soc);
663   }
664   RecompilationSchedule::serialize(soc);
665 }
666 
667 class TrainingDataPrinter : StackObj {
668   outputStream* _st;
669   int _index;
670 public:
671   TrainingDataPrinter(outputStream* st) : _st(st), _index(0) {}
672   void do_value(TrainingData* td) {
673     const char* type = (td->is_KlassTrainingData()   ? "K" :
674                         td->is_MethodTrainingData()  ? "M" :
675                         td->is_CompileTrainingData() ? "C" : "?");
676     _st->print("%4d: %p %s ", _index++, td, type);
677     td->print_on(_st);
678     _st->cr();
679     if (td->is_KlassTrainingData()) {
680       td->as_KlassTrainingData()->iterate_comp_deps([&](CompileTrainingData* ctd) {
681         ResourceMark rm;
682         _st->print_raw("  C ");
683         ctd->print_on(_st);
684         _st->cr();
685       });
686     } else if (td->is_MethodTrainingData()) {
687       td->as_MethodTrainingData()->iterate_compiles([&](CompileTrainingData* ctd) {
688         ResourceMark rm;
689         _st->print_raw("  C ");
690         ctd->print_on(_st);
691         _st->cr();
692       });
693     } else if (td->is_CompileTrainingData()) {
694       // ?
695     }
696   }
697 };
698 
699 void TrainingData::print_archived_training_data_on(outputStream* st) {
700   st->print_cr("Archived TrainingData Dictionary");
701   TrainingDataPrinter tdp(st);
702   TrainingDataLocker::initialize();
703   _archived_training_data_dictionary.iterate_all(&tdp);
704   RecompilationSchedule::print_archived_training_data_on(st);
705 }
706 
707 void TrainingData::Key::metaspace_pointers_do(MetaspaceClosure *iter) {
708   iter->push(const_cast<Metadata**>(&_meta));
709 }
710 
711 void TrainingData::metaspace_pointers_do(MetaspaceClosure* iter) {
712   _key.metaspace_pointers_do(iter);
713 }
714 
715 bool TrainingData::Key::can_compute_cds_hash(const Key* const& k) {
716   return k->meta() == nullptr || MetaspaceObj::in_aot_cache(k->meta());
717 }
718 
719 uint TrainingData::Key::cds_hash(const Key* const& k) {
720   return SystemDictionaryShared::hash_for_shared_dictionary((address)k->meta());
721 }
722 
723 TrainingData* TrainingData::lookup_archived_training_data(const Key* k) {
724   assert(!need_data(), "Should be used only in read-only mode");
725   // For this to work, all components of the key must be in shared metaspace.
726   if (!TrainingData::Key::can_compute_cds_hash(k) || _archived_training_data_dictionary.empty()) {
727     return nullptr;
728   }
729   uint hash = TrainingData::Key::cds_hash(k);
730   TrainingData* td = _archived_training_data_dictionary.lookup(k, hash, -1 /*unused*/);
731   if (td != nullptr) {
732     if ((td->is_KlassTrainingData()  && td->as_KlassTrainingData()->has_holder()) ||
733         (td->is_MethodTrainingData() && td->as_MethodTrainingData()->has_holder())) {
734       return td;
735     } else {
736       ShouldNotReachHere();
737     }
738   }
739   return nullptr;
740 }
741 
742 template <typename T>
743 void TrainingData::DepList<T>::metaspace_pointers_do(MetaspaceClosure* iter) {
744   iter->push(&_deps);
745 }
746 
747 void KlassTrainingData::metaspace_pointers_do(MetaspaceClosure* iter) {
748   log_trace(aot, training)("Iter(KlassTrainingData): %p", this);
749   TrainingData::metaspace_pointers_do(iter);
750   _comp_deps.metaspace_pointers_do(iter);
751   iter->push(&_holder);
752 }
753 
754 void MethodTrainingData::metaspace_pointers_do(MetaspaceClosure* iter) {
755   log_trace(aot, training)("Iter(MethodTrainingData): %p", this);
756   TrainingData::metaspace_pointers_do(iter);
757   iter->push(&_klass);
758   iter->push((Method**)&_holder);
759   for (int i = 0; i < CompLevel_count - 1; i++) {
760     iter->push(&_last_toplevel_compiles[i]);
761   }
762   iter->push(&_final_profile);
763   iter->push(&_final_counters);
764 }
765 
766 void CompileTrainingData::metaspace_pointers_do(MetaspaceClosure* iter) {
767   log_trace(aot, training)("Iter(CompileTrainingData): %p", this);
768   TrainingData::metaspace_pointers_do(iter);
769   _init_deps.metaspace_pointers_do(iter);
770   _ci_records.metaspace_pointers_do(iter);
771   iter->push(&_method);
772 }
773 
774 template <typename T>
775 void TrainingData::DepList<T>::prepare() {
776   if (_deps == nullptr && _deps_dyn != nullptr) {
777     int len = _deps_dyn->length();
778     _deps = MetadataFactory::new_array_from_c_heap<T>(len, mtClassShared);
779     for (int i = 0; i < len; i++) {
780       _deps->at_put(i, _deps_dyn->at(i)); // copy
781     }
782     _deps_dyn = nullptr;
783   }
784 }
785 
786 void KlassTrainingData::remove_unshareable_info() {
787   TrainingData::remove_unshareable_info();
788   _comp_deps.remove_unshareable_info();
789 }
790 
791 void MethodTrainingData::remove_unshareable_info() {
792   TrainingData::remove_unshareable_info();
793   if (_final_counters != nullptr) {
794     _final_counters->remove_unshareable_info();
795   }
796   if (_final_profile != nullptr) {
797     _final_profile->remove_unshareable_info();
798   }
799 }
800 
801 void CompileTrainingData::remove_unshareable_info() {
802   TrainingData::remove_unshareable_info();
803   _init_deps.remove_unshareable_info();
804   _ci_records.remove_unshareable_info();
805   _init_deps_left = compute_init_deps_left(true);
806 }