1 /*
  2  * Copyright (c) 1999, 2026, 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 "ci/ciField.hpp"
 26 #include "ci/ciInstance.hpp"
 27 #include "ci/ciInstanceKlass.hpp"
 28 #include "ci/ciUtilities.inline.hpp"
 29 #include "classfile/javaClasses.hpp"
 30 #include "classfile/vmClasses.hpp"
 31 #include "memory/allocation.hpp"
 32 #include "memory/allocation.inline.hpp"
 33 #include "memory/resourceArea.hpp"
 34 #include "oops/fieldStreams.inline.hpp"
 35 #include "oops/instanceKlass.inline.hpp"
 36 #include "oops/klass.inline.hpp"
 37 #include "oops/oop.inline.hpp"
 38 #include "runtime/fieldDescriptor.inline.hpp"
 39 #include "runtime/handles.inline.hpp"
 40 #include "runtime/jniHandles.inline.hpp"
 41 
 42 // ciInstanceKlass
 43 //
 44 // This class represents a Klass* in the HotSpot virtual machine
 45 // whose Klass part in an InstanceKlass.
 46 
 47 
 48 // ------------------------------------------------------------------
 49 // ciInstanceKlass::ciInstanceKlass
 50 //
 51 // Loaded instance klass.
 52 ciInstanceKlass::ciInstanceKlass(Klass* k) :
 53   ciKlass(k)
 54 {
 55   assert(get_Klass()->is_instance_klass(), "wrong type");
 56   assert(get_instanceKlass()->is_loaded(), "must be at least loaded");
 57   InstanceKlass* ik = get_instanceKlass();
 58 
 59   AccessFlags access_flags = ik->access_flags();
 60   _flags = ciFlags(access_flags);
 61   _has_finalizer = ik->has_finalizer();
 62   _has_subklass = flags().is_final() ? subklass_false : subklass_unknown;
 63   _init_state = ik->init_state();
 64   _has_nonstatic_fields = ik->has_nonstatic_fields();
 65   _has_nonstatic_concrete_methods = ik->has_nonstatic_concrete_methods();
 66   _is_hidden = ik->is_hidden();
 67   _is_record = ik->is_record();
 68   _trust_final_fields = ik->trust_final_fields();
 69   _nonstatic_fields = nullptr; // initialized lazily by compute_nonstatic_fields:
 70   _has_injected_fields = -1;
 71   _implementor = nullptr; // we will fill these lazily
 72   _transitive_interfaces = nullptr;
 73 
 74   // Ensure that the metadata wrapped by the ciMetadata is kept alive by GC.
 75   // This is primarily useful for metadata which is considered as weak roots
 76   // by the GC but need to be strong roots if reachable from a current compilation.
 77   // InstanceKlass are created for both weak and strong metadata.  Ensuring this metadata
 78   // alive covers the cases where there are weak roots without performance cost.
 79   oop holder = ik->klass_holder();
 80   if (ik->class_loader_data()->has_class_mirror_holder()) {
 81     // Though ciInstanceKlass records class loader oop, it's not enough to keep
 82     // non-strong hidden classes alive (loader == nullptr). Klass holder should
 83     // be used instead. It is enough to record a ciObject, since cached elements are never removed
 84     // during ciObjectFactory lifetime. ciObjectFactory itself is created for
 85     // every compilation and lives for the whole duration of the compilation.
 86     assert(holder != nullptr, "holder of hidden class is the mirror which is never null");
 87     (void)CURRENT_ENV->get_object(holder);
 88   }
 89 
 90   JavaThread *thread = JavaThread::current();
 91   if (ciObjectFactory::is_initialized()) {
 92     _loader = JNIHandles::make_local(thread, ik->class_loader());
 93     _is_shared = false;
 94   } else {
 95     Handle h_loader(thread, ik->class_loader());
 96     _loader = JNIHandles::make_global(h_loader);
 97     _is_shared = true;
 98   }
 99 
100   _has_trusted_loader = compute_has_trusted_loader();
101 
102   // Lazy fields get filled in only upon request.
103   _super  = nullptr;
104   _java_mirror = nullptr;
105 
106   if (is_shared()) {
107     if (k != vmClasses::Object_klass()) {
108       super();
109     }
110     //compute_nonstatic_fields();  // done outside of constructor
111   }
112 
113   _field_cache = nullptr;
114 }
115 
116 // Version for unloaded classes:
117 ciInstanceKlass::ciInstanceKlass(ciSymbol* name,
118                                  jobject loader)
119   : ciKlass(name, T_OBJECT)
120 {
121   assert(name->char_at(0) != JVM_SIGNATURE_ARRAY, "not an instance klass");
122   _init_state = (InstanceKlass::ClassState)0;
123   _has_nonstatic_fields = false;
124   _nonstatic_fields = nullptr;
125   _has_injected_fields = -1;
126   _is_hidden = false;
127   _is_record = false;
128   _loader = loader;
129   _is_shared = false;
130   _super = nullptr;
131   _java_mirror = nullptr;
132   _field_cache = nullptr;
133   _has_trusted_loader = compute_has_trusted_loader();
134 }
135 
136 
137 
138 // ------------------------------------------------------------------
139 InstanceKlass::ClassState ciInstanceKlass::compute_init_state() {
140   if (_is_shared && is_loaded()) {
141     // Return cached init state of shared klass
142     ciEnv* env = CURRENT_ENV;
143     assert(env->task() != nullptr, "only calls from compilation are expected here");
144     return env->get_cached_init_state(ident());
145   }
146   return _init_state;
147 }
148 
149 // ------------------------------------------------------------------
150 // ciInstanceKlass::compute_shared_has_subklass
151 bool ciInstanceKlass::compute_shared_has_subklass() {
152   GUARDED_VM_ENTRY(
153     InstanceKlass* ik = get_instanceKlass();
154     _has_subklass = ik->subklass() != nullptr ? subklass_true : subklass_false;
155     return _has_subklass == subklass_true;
156   )
157 }
158 
159 // ------------------------------------------------------------------
160 // ciInstanceKlass::loader
161 oop ciInstanceKlass::loader() {
162   ASSERT_IN_VM;
163   return JNIHandles::resolve(_loader);
164 }
165 
166 // ------------------------------------------------------------------
167 // ciInstanceKlass::loader_handle
168 jobject ciInstanceKlass::loader_handle() {
169   return _loader;
170 }
171 
172 // ------------------------------------------------------------------
173 // ciInstanceKlass::field_cache
174 //
175 // Get the field cache associated with this klass.
176 ciConstantPoolCache* ciInstanceKlass::field_cache() {
177   if (is_shared()) {
178     return nullptr;
179   }
180   if (_field_cache == nullptr) {
181     assert(!is_java_lang_Object(), "Object has no fields");
182     Arena* arena = CURRENT_ENV->arena();
183     _field_cache = new (arena) ciConstantPoolCache(arena, 5);
184   }
185   return _field_cache;
186 }
187 
188 // ------------------------------------------------------------------
189 // ciInstanceKlass::get_canonical_holder
190 //
191 ciInstanceKlass* ciInstanceKlass::get_canonical_holder(int offset) {
192   #ifdef ASSERT
193   if (!(offset >= 0 && offset < layout_helper_size_in_bytes())) {
194     tty->print("*** get_canonical_holder(%d) on ", offset);
195     this->print();
196     tty->print_cr(" ***");
197   };
198   assert(offset >= 0 && offset < layout_helper_size_in_bytes(), "offset must be tame");
199   #endif
200 
201   if (offset < instanceOopDesc::base_offset_in_bytes()) {
202     // All header offsets belong properly to java/lang/Object.
203     return CURRENT_ENV->Object_klass();
204   }
205 
206   ciInstanceKlass* self = this;
207   assert(self->is_loaded(), "must be loaded to access field info");
208   ciField* field = self->get_field_by_offset(offset, false);
209   if (field != nullptr) {
210     return field->holder();
211   } else {
212     for (;;) {
213       assert(self->is_loaded(), "must be loaded to have size");
214       ciInstanceKlass* super = self->super();
215       if (super == nullptr ||
216           super->nof_nonstatic_fields() == 0 ||
217           super->layout_helper_size_in_bytes() <= offset) {
218         return self;
219       } else {
220         self = super;  // return super->get_canonical_holder(offset)
221       }
222     }
223   }
224 }
225 
226 // ------------------------------------------------------------------
227 // ciInstanceKlass::is_java_lang_Object
228 //
229 // Is this klass java.lang.Object?
230 bool ciInstanceKlass::is_java_lang_Object() const {
231   return equals(CURRENT_ENV->Object_klass());
232 }
233 
234 // ------------------------------------------------------------------
235 // ciInstanceKlass::uses_default_loader
236 bool ciInstanceKlass::uses_default_loader() const {
237   // Note:  We do not need to resolve the handle or enter the VM
238   // in order to test null-ness.
239   return _loader == nullptr;
240 }
241 
242 // ------------------------------------------------------------------
243 
244 /**
245  * Return basic type of boxed value for box klass or T_OBJECT if not.
246  */
247 BasicType ciInstanceKlass::box_klass_type() const {
248   if (uses_default_loader() && is_loaded()) {
249     return vmClasses::box_klass_type(get_Klass());
250   } else {
251     return T_OBJECT;
252   }
253 }
254 
255 /**
256  * Is this boxing klass?
257  */
258 bool ciInstanceKlass::is_box_klass() const {
259   return is_java_primitive(box_klass_type());
260 }
261 
262 /**
263  *  Is this boxed value offset?
264  */
265 bool ciInstanceKlass::is_boxed_value_offset(int offset) const {
266   BasicType bt = box_klass_type();
267   return is_java_primitive(bt) &&
268          (offset == java_lang_boxing_object::value_offset(bt));
269 }
270 
271 // ------------------------------------------------------------------
272 // ciInstanceKlass::is_in_package
273 //
274 // Is this klass in the given package?
275 bool ciInstanceKlass::is_in_package(const char* packagename, int len) {
276   // To avoid class loader mischief, this test always rejects application classes.
277   if (!uses_default_loader())
278     return false;
279   GUARDED_VM_ENTRY(
280     return is_in_package_impl(packagename, len);
281   )
282 }
283 
284 bool ciInstanceKlass::is_in_package_impl(const char* packagename, int len) {
285   ASSERT_IN_VM;
286 
287   // If packagename contains trailing '/' exclude it from the
288   // prefix-test since we test for it explicitly.
289   if (packagename[len - 1] == '/')
290     len--;
291 
292   if (!name()->starts_with(packagename, len))
293     return false;
294 
295   // Test if the class name is something like "java/lang".
296   if ((len + 1) > name()->utf8_length())
297     return false;
298 
299   // Test for trailing '/'
300   if (name()->char_at(len) != '/')
301     return false;
302 
303   // Make sure it's not actually in a subpackage:
304   if (name()->index_of_at(len+1, "/", 1) >= 0)
305     return false;
306 
307   return true;
308 }
309 
310 // ------------------------------------------------------------------
311 // ciInstanceKlass::print_impl
312 //
313 // Implementation of the print method.
314 void ciInstanceKlass::print_impl(outputStream* st) {
315   ciKlass::print_impl(st);
316   GUARDED_VM_ENTRY(st->print(" loader=" INTPTR_FORMAT, p2i(loader()));)
317   if (is_loaded()) {
318     st->print(" initialized=%s finalized=%s subklass=%s size=%d flags=",
319               bool_to_str(is_initialized()),
320               bool_to_str(has_finalizer()),
321               bool_to_str(has_subklass()),
322               layout_helper());
323 
324     _flags.print_klass_flags(st);
325 
326     if (_super) {
327       st->print(" super=");
328       _super->print_name_on(st);
329     }
330     if (_java_mirror) {
331       st->print(" mirror=PRESENT");
332     }
333   }
334 }
335 
336 // ------------------------------------------------------------------
337 // ciInstanceKlass::super
338 //
339 // Get the superklass of this klass.
340 ciInstanceKlass* ciInstanceKlass::super() {
341   assert(is_loaded(), "must be loaded");
342   if (_super == nullptr && !is_java_lang_Object()) {
343     GUARDED_VM_ENTRY(
344       Klass* super_klass = get_instanceKlass()->super();
345       _super = CURRENT_ENV->get_instance_klass(super_klass);
346     )
347   }
348   return _super;
349 }
350 
351 // ------------------------------------------------------------------
352 // ciInstanceKlass::java_mirror
353 //
354 // Get the instance of java.lang.Class corresponding to this klass.
355 // Cache it on this->_java_mirror.
356 ciInstance* ciInstanceKlass::java_mirror() {
357   if (is_shared()) {
358     return ciKlass::java_mirror();
359   }
360   if (_java_mirror == nullptr) {
361     _java_mirror = ciKlass::java_mirror();
362   }
363   return _java_mirror;
364 }
365 
366 // ------------------------------------------------------------------
367 // ciInstanceKlass::unique_concrete_subklass
368 ciInstanceKlass* ciInstanceKlass::unique_concrete_subklass() {
369   if (!is_loaded())     return nullptr; // No change if class is not loaded
370   if (!is_abstract())   return nullptr; // Only applies to abstract classes.
371   if (!has_subklass())  return nullptr; // Must have at least one subklass.
372   VM_ENTRY_MARK;
373   InstanceKlass* ik = get_instanceKlass();
374   Klass* up = ik->up_cast_abstract();
375   assert(up->is_instance_klass(), "must be InstanceKlass");
376   if (ik == up) {
377     return nullptr;
378   }
379   return CURRENT_THREAD_ENV->get_instance_klass(up);
380 }
381 
382 // ------------------------------------------------------------------
383 // ciInstanceKlass::has_finalizable_subclass
384 bool ciInstanceKlass::has_finalizable_subclass() {
385   if (!is_loaded())     return true;
386   VM_ENTRY_MARK;
387   return Dependencies::find_finalizable_subclass(get_instanceKlass()) != nullptr;
388 }
389 
390 // ------------------------------------------------------------------
391 // ciInstanceKlass::contains_field_offset
392 bool ciInstanceKlass::contains_field_offset(int offset) {
393   VM_ENTRY_MARK;
394   return get_instanceKlass()->contains_field_offset(offset);
395 }
396 
397 ciField* ciInstanceKlass::get_nonstatic_field_by_offset(const int field_offset) {
398   for (int i = 0, len = nof_nonstatic_fields(); i < len; i++) {
399     ciField* field = _nonstatic_fields->at(i);
400     int field_off = field->offset_in_bytes();
401     if (field_off == field_offset)
402       return field;
403   }
404   return nullptr;
405 }
406 
407 // ------------------------------------------------------------------
408 // ciInstanceKlass::get_field_by_offset
409 ciField* ciInstanceKlass::get_field_by_offset(int field_offset, bool is_static) {
410   if (!is_static) {
411     return get_nonstatic_field_by_offset(field_offset);
412   }
413   VM_ENTRY_MARK;
414   InstanceKlass* k = get_instanceKlass();
415   fieldDescriptor fd;
416   if (!k->find_field_from_offset(field_offset, is_static, &fd)) {
417     return nullptr;
418   }
419   ciField* field = new (CURRENT_THREAD_ENV->arena()) ciField(&fd);
420   return field;
421 }
422 
423 // ------------------------------------------------------------------
424 // ciInstanceKlass::get_field_by_name
425 ciField* ciInstanceKlass::get_field_by_name(ciSymbol* name, ciSymbol* signature, bool is_static) {
426   VM_ENTRY_MARK;
427   InstanceKlass* k = get_instanceKlass();
428   fieldDescriptor fd;
429   Klass* def = k->find_field(name->get_symbol(), signature->get_symbol(), is_static, &fd);
430   if (def == nullptr) {
431     return nullptr;
432   }
433   ciField* field = new (CURRENT_THREAD_ENV->arena()) ciField(&fd);
434   return field;
435 }
436 
437 #ifdef ASSERT
438 static void assert_injected_field(InternalFieldStream& fs) {
439   assert(!fs.done(), "invarinat");
440   fieldDescriptor fd = fs.field_descriptor();
441   assert(fd.is_injected(), "invariant");
442 }
443 #endif
444 
445 // ------------------------------------------------------------------
446 // ciInstanceKlass::get_injected_instance_field_by_name
447 //
448 // Implements also compute_injected_fields().
449 //
450 ciField* ciInstanceKlass::get_injected_instance_field_by_name(ciSymbol* name, ciSymbol* signature) {
451   VM_ENTRY_MARK;
452   InstanceKlass* const k = get_instanceKlass();
453   const Symbol* const name_symbol = name->get_symbol();
454   assert(name_symbol != nullptr, "invariant");
455   const Symbol* const sig_sym = signature->get_symbol();
456   assert(sig_sym != nullptr, "invariant");
457 
458   if (_has_injected_fields == -1) {
459     if (super() != nullptr && super()->has_injected_fields()) {
460       _has_injected_fields = 1;
461     }
462   }
463 
464   ciField* injected = nullptr;
465   for (InternalFieldStream fs(k); !fs.done(); fs.next()) {
466     if (fs.access_flags().is_static())  continue;
467     DEBUG_ONLY(assert_injected_field(fs);)
468     if (_has_injected_fields == -1) {
469       _has_injected_fields = 1;
470     }
471     if (fs.name() == name_symbol && fs.signature() == sig_sym) {
472       fieldDescriptor fd = fs.field_descriptor();
473       assert(fd.is_injected(), "invariant");
474       injected = new (CURRENT_THREAD_ENV->arena()) ciField(&fd);
475       break;
476     }
477   }
478 
479   if (_has_injected_fields == -1) {
480     _has_injected_fields = 0;
481   }
482 
483   return injected;
484 }
485 
486 // This is essentially a shortcut for:
487 //   get_field_by_offset(field_offset, is_static)->layout_type()
488 // except this does not require allocating memory for a new ciField
489 BasicType ciInstanceKlass::get_field_type_by_offset(const int field_offset, const bool is_static) {
490   if (!is_static) {
491     ciField* field = get_nonstatic_field_by_offset(field_offset);
492     return field != nullptr ? field->layout_type() : T_ILLEGAL;
493   }
494 
495   // Avoid allocating a new ciField by obtaining the field type directly
496   VM_ENTRY_MARK;
497   InstanceKlass* k = get_instanceKlass();
498   fieldDescriptor fd;
499   if (!k->find_field_from_offset(field_offset, is_static, &fd)) {
500     return T_ILLEGAL;
501   }
502 
503   // Reproduce the behavior of ciField::layout_type
504   BasicType field_type = fd.field_type();
505   if (is_reference_type(field_type)) {
506     return T_OBJECT;
507   }
508   return type2field[make(field_type)->basic_type()];
509 }
510 
511 // ------------------------------------------------------------------
512 // ciInstanceKlass::compute_nonstatic_fields
513 int ciInstanceKlass::compute_nonstatic_fields() {
514   assert(is_loaded(), "must be loaded");
515 
516   if (_nonstatic_fields != nullptr)
517     return _nonstatic_fields->length();
518 
519   if (!has_nonstatic_fields()) {
520     Arena* arena = CURRENT_ENV->arena();
521     _nonstatic_fields = new (arena) GrowableArray<ciField*>(arena, 0, 0, nullptr);
522     return 0;
523   }
524   assert(!is_java_lang_Object(), "bootstrap OK");
525 
526   ciInstanceKlass* super = this->super();
527   GrowableArray<ciField*>* super_fields = nullptr;
528   if (super != nullptr && super->has_nonstatic_fields()) {
529     int super_flen   = super->nof_nonstatic_fields();
530     super_fields = super->_nonstatic_fields;
531     assert(super_flen == 0 || super_fields != nullptr, "first get nof_fields");
532   }
533 
534   GrowableArray<ciField*>* fields = nullptr;
535   GUARDED_VM_ENTRY({
536       fields = compute_nonstatic_fields_impl(super_fields);
537     });
538 
539   if (fields == nullptr) {
540     // This can happen if this class (java.lang.Class) has invisible fields.
541     if (super_fields != nullptr) {
542       _nonstatic_fields = super_fields;
543       return super_fields->length();
544     } else {
545       return 0;
546     }
547   }
548 
549   int flen = fields->length();
550 
551   _nonstatic_fields = fields;
552   return flen;
553 }
554 
555 GrowableArray<ciField*>*
556 ciInstanceKlass::compute_nonstatic_fields_impl(GrowableArray<ciField*>*
557                                                super_fields) {
558   ASSERT_IN_VM;
559   Arena* arena = CURRENT_ENV->arena();
560   int flen = 0;
561   GrowableArray<ciField*>* fields = nullptr;
562   InstanceKlass* k = get_instanceKlass();
563   for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
564     if (fs.access_flags().is_static())  continue;
565     flen += 1;
566   }
567 
568   // allocate the array:
569   if (flen == 0) {
570     return nullptr;  // return nothing if none are locally declared
571   }
572   if (super_fields != nullptr) {
573     flen += super_fields->length();
574   }
575   fields = new (arena) GrowableArray<ciField*>(arena, flen, 0, nullptr);
576   if (super_fields != nullptr) {
577     fields->appendAll(super_fields);
578   }
579 
580   for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
581     if (fs.access_flags().is_static())  continue;
582     fieldDescriptor& fd = fs.field_descriptor();
583     ciField* field = new (arena) ciField(&fd);
584     fields->append(field);
585   }
586   assert(fields->length() == flen, "sanity");
587   return fields;
588 }
589 
590 bool ciInstanceKlass::compute_injected_fields_helper() {
591   ASSERT_IN_VM;
592   InstanceKlass* k = get_instanceKlass();
593 
594   for (InternalFieldStream fs(k); !fs.done(); fs.next()) {
595     if (fs.access_flags().is_static())  continue;
596     return true;
597   }
598   return false;
599 }
600 
601 void ciInstanceKlass::compute_injected_fields() {
602   assert(is_loaded(), "must be loaded");
603 
604   int has_injected_fields = 0;
605   if (super() != nullptr && super()->has_injected_fields()) {
606     has_injected_fields = 1;
607   } else {
608     GUARDED_VM_ENTRY({
609         has_injected_fields = compute_injected_fields_helper() ? 1 : 0;
610       });
611   }
612   // may be concurrently initialized for shared ciInstanceKlass objects
613   assert(_has_injected_fields == -1 || _has_injected_fields == has_injected_fields, "broken concurrent initialization");
614   _has_injected_fields = has_injected_fields;
615 }
616 
617 bool ciInstanceKlass::has_object_fields() const {
618   GUARDED_VM_ENTRY(
619       return get_instanceKlass()->nonstatic_oop_map_size() > 0;
620     );
621 }
622 
623 bool ciInstanceKlass::compute_has_trusted_loader() {
624   ASSERT_IN_VM;
625   oop loader_oop = loader();
626   if (loader_oop == nullptr) {
627     return true; // bootstrap class loader
628   }
629   return java_lang_ClassLoader::is_trusted_loader(loader_oop);
630 }
631 
632 bool ciInstanceKlass::has_class_initializer() {
633   VM_ENTRY_MARK;
634   return get_instanceKlass()->class_initializer() != nullptr;
635 }
636 
637 // ------------------------------------------------------------------
638 // ciInstanceKlass::find_method
639 //
640 // Find a method in this klass.
641 ciMethod* ciInstanceKlass::find_method(ciSymbol* name, ciSymbol* signature) {
642   VM_ENTRY_MARK;
643   InstanceKlass* k = get_instanceKlass();
644   Symbol* name_sym = name->get_symbol();
645   Symbol* sig_sym= signature->get_symbol();
646 
647   Method* m = k->find_method(name_sym, sig_sym);
648   if (m == nullptr)  return nullptr;
649 
650   return CURRENT_THREAD_ENV->get_method(m);
651 }
652 
653 // ------------------------------------------------------------------
654 // ciInstanceKlass::is_leaf_type
655 bool ciInstanceKlass::is_leaf_type() {
656   assert(is_loaded(), "must be loaded");
657   if (is_shared()) {
658     return is_final();  // approximately correct
659   } else {
660     return !has_subklass() && (!is_interface() || nof_implementors() == 0);
661   }
662 }
663 
664 // ------------------------------------------------------------------
665 // ciInstanceKlass::implementor
666 //
667 // Report an implementor of this interface.
668 // Note that there are various races here, since my copy
669 // of _nof_implementors might be out of date with respect
670 // to results returned by InstanceKlass::implementor.
671 // This is OK, since any dependencies we decide to assert
672 // will be checked later under the Compile_lock.
673 ciInstanceKlass* ciInstanceKlass::implementor() {
674   assert(is_interface(), "required");
675   ciInstanceKlass* impl = _implementor;
676   if (impl == nullptr) {
677     if (is_shared()) {
678       impl = this; // assume a well-known interface never has a unique implementor
679     } else {
680       // Go into the VM to fetch the implementor.
681       VM_ENTRY_MARK;
682       InstanceKlass* ik = get_instanceKlass();
683       Klass* implk = ik->implementor();
684       if (implk != nullptr) {
685         if (implk == ik) {
686           // More than one implementors. Use 'this' in this case.
687           impl = this;
688         } else {
689           impl = CURRENT_THREAD_ENV->get_instance_klass(implk);
690         }
691       }
692     }
693     // Memoize this result.
694     _implementor = impl;
695   }
696   return impl;
697 }
698 
699 // Utility class for printing of the contents of the static fields for
700 // use by compilation replay.  It only prints out the information that
701 // could be consumed by the compiler, so for primitive types it prints
702 // out the actual value.  For Strings it's the actual string value.
703 // For array types it it's first level array size since that's the
704 // only value which statically unchangeable.  For all other reference
705 // types it simply prints out the dynamic type.
706 
707 class StaticFinalFieldPrinter : public FieldClosure {
708   outputStream* _out;
709   const char*   _holder;
710  public:
711   StaticFinalFieldPrinter(outputStream* out, const char* holder) :
712     _out(out),
713     _holder(holder) {
714   }
715   void do_field(fieldDescriptor* fd) {
716     if (fd->is_final() && !fd->has_initial_value()) {
717       ResourceMark rm;
718       oop mirror = fd->field_holder()->java_mirror();
719       _out->print("staticfield %s %s %s ", _holder, fd->name()->as_quoted_ascii(), fd->signature()->as_quoted_ascii());
720       BasicType field_type = fd->field_type();
721       switch (field_type) {
722         case T_BYTE:    _out->print_cr("%d", mirror->byte_field(fd->offset()));   break;
723         case T_BOOLEAN: _out->print_cr("%d", mirror->bool_field(fd->offset()));   break;
724         case T_SHORT:   _out->print_cr("%d", mirror->short_field(fd->offset()));  break;
725         case T_CHAR:    _out->print_cr("%d", mirror->char_field(fd->offset()));   break;
726         case T_INT:     _out->print_cr("%d", mirror->int_field(fd->offset()));    break;
727         case T_LONG:    _out->print_cr(INT64_FORMAT, (int64_t)(mirror->long_field(fd->offset())));   break;
728         case T_FLOAT: {
729           float f = mirror->float_field(fd->offset());
730           _out->print_cr("%d", *(int*)&f);
731           break;
732         }
733         case T_DOUBLE: {
734           double d = mirror->double_field(fd->offset());
735           _out->print_cr(INT64_FORMAT, *(int64_t*)&d);
736           break;
737         }
738         case T_ARRAY:  // fall-through
739         case T_OBJECT: {
740           oop value =  mirror->obj_field_acquire(fd->offset());
741           if (value == nullptr) {
742             if (field_type == T_ARRAY) {
743               _out->print("%d", -1);
744             }
745             _out->cr();
746           } else if (value->is_instance()) {
747             assert(field_type == T_OBJECT, "");
748             if (value->is_a(vmClasses::String_klass())) {
749               const char* ascii_value = java_lang_String::as_quoted_ascii(value);
750               _out->print_cr("\"%s\"", (ascii_value != nullptr) ? ascii_value : "");
751             } else {
752               const char* klass_name  = value->klass()->name()->as_quoted_ascii();
753               _out->print_cr("%s", klass_name);
754             }
755           } else if (value->is_array()) {
756             typeArrayOop ta = (typeArrayOop)value;
757             _out->print("%d", ta->length());
758             if (value->is_objArray()) {
759               objArrayOop oa = (objArrayOop)value;
760               const char* klass_name  = value->klass()->name()->as_quoted_ascii();
761               _out->print(" %s", klass_name);
762             }
763             _out->cr();
764           } else {
765             ShouldNotReachHere();
766           }
767           break;
768         }
769         default:
770           ShouldNotReachHere();
771         }
772     }
773   }
774 };
775 
776 const char *ciInstanceKlass::replay_name() const {
777   return CURRENT_ENV->replay_name(get_instanceKlass());
778 }
779 
780 void ciInstanceKlass::dump_replay_instanceKlass(outputStream* out, InstanceKlass* ik) {
781   if (ik->is_hidden()) {
782     const char *name = CURRENT_ENV->dyno_name(ik);
783     if (name != nullptr) {
784       out->print_cr("instanceKlass %s # %s", name, ik->name()->as_quoted_ascii());
785     } else {
786       out->print_cr("# instanceKlass %s", ik->name()->as_quoted_ascii());
787     }
788   } else {
789     out->print_cr("instanceKlass %s", ik->name()->as_quoted_ascii());
790   }
791 }
792 
793 GrowableArray<ciInstanceKlass*>* ciInstanceKlass::transitive_interfaces() const{
794   if (_transitive_interfaces == nullptr) {
795     const_cast<ciInstanceKlass*>(this)->compute_transitive_interfaces();
796   }
797   return _transitive_interfaces;
798 }
799 
800 void ciInstanceKlass::compute_transitive_interfaces() {
801   GUARDED_VM_ENTRY(
802           InstanceKlass* ik = get_instanceKlass();
803           Array<InstanceKlass*>* interfaces = ik->transitive_interfaces();
804           int orig_length = interfaces->length();
805           Arena* arena = CURRENT_ENV->arena();
806           int transitive_interfaces_len = orig_length + (is_interface() ? 1 : 0);
807           GrowableArray<ciInstanceKlass*>* transitive_interfaces = new(arena)GrowableArray<ciInstanceKlass*>(arena, transitive_interfaces_len,
808                                                                                                              0, nullptr);
809           for (int i = 0; i < orig_length; i++) {
810             transitive_interfaces->append(CURRENT_ENV->get_instance_klass(interfaces->at(i)));
811           }
812           if (is_interface()) {
813             transitive_interfaces->append(this);
814           }
815           _transitive_interfaces = transitive_interfaces;
816   );
817 }
818 
819 void ciInstanceKlass::dump_replay_data(outputStream* out) {
820   ResourceMark rm;
821 
822   InstanceKlass* ik = get_instanceKlass();
823   ConstantPool*  cp = ik->constants();
824 
825   // Try to record related loaded classes
826   Klass* sub = ik->subklass();
827   while (sub != nullptr) {
828     if (sub->is_instance_klass()) {
829       InstanceKlass *isub = InstanceKlass::cast(sub);
830       dump_replay_instanceKlass(out, isub);
831     }
832     sub = sub->next_sibling();
833   }
834 
835   // Dump out the state of the constant pool tags.  During replay the
836   // tags will be validated for things which shouldn't change and
837   // classes will be resolved if the tags indicate that they were
838   // resolved at compile time.
839   const char *name = replay_name();
840   out->print("ciInstanceKlass %s %d %d %d", name,
841              is_linked(), is_initialized(), cp->length());
842   for (int index = 1; index < cp->length(); index++) {
843     out->print(" %d", cp->tags()->at(index));
844   }
845   out->cr();
846   if (is_initialized()) {
847     //  Dump out the static final fields in case the compilation relies
848     //  on their value for correct replay.
849     StaticFinalFieldPrinter sffp(out, name);
850     ik->do_local_static_fields(&sffp);
851   }
852 }
853 
854 #ifdef ASSERT
855 bool ciInstanceKlass::debug_final_field_at(int offset) {
856   GUARDED_VM_ENTRY(
857     InstanceKlass* ik = get_instanceKlass();
858     fieldDescriptor fd;
859     if (ik->find_field_from_offset(offset, false, &fd)) {
860       return fd.is_final();
861     }
862   );
863   return false;
864 }
865 
866 bool ciInstanceKlass::debug_stable_field_at(int offset) {
867   GUARDED_VM_ENTRY(
868     InstanceKlass* ik = get_instanceKlass();
869     fieldDescriptor fd;
870     if (ik->find_field_from_offset(offset, false, &fd)) {
871       return fd.is_stable();
872     }
873   );
874   return false;
875 }
876 #endif