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