1 /*
  2  * Copyright (c) 1999, 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.
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 23  */
 24 
 25 #ifndef SHARE_CI_CIINSTANCEKLASS_HPP
 26 #define SHARE_CI_CIINSTANCEKLASS_HPP
 27 
 28 #include "ci/ciConstantPoolCache.hpp"
 29 #include "ci/ciFlags.hpp"
 30 #include "ci/ciKlass.hpp"
 31 #include "ci/ciSymbol.hpp"
 32 #include "oops/instanceKlass.hpp"
 33 
 34 // ciInstanceKlass
 35 //
 36 // This class represents a Klass* in the HotSpot virtual machine
 37 // whose Klass part is an InstanceKlass.  It may or may not
 38 // be loaded.
 39 class ciInstanceKlass : public ciKlass {
 40   CI_PACKAGE_ACCESS
 41   friend class ciBytecodeStream;
 42   friend class ciEnv;
 43   friend class ciExceptionHandler;
 44   friend class ciMethod;
 45   friend class ciField;
 46   friend class ciReplay;
 47   friend class CompileTrainingData;
 48 
 49 private:
 50   enum SubklassValue { subklass_unknown, subklass_false, subklass_true };
 51 
 52   jobject                _loader;
 53 
 54   InstanceKlass::ClassState _init_state;           // state of class
 55   bool                   _is_shared;
 56   bool                   _has_finalizer;
 57   SubklassValue          _has_subklass;
 58   bool                   _has_nonstatic_fields;
 59   bool                   _has_nonstatic_concrete_methods;
 60   bool                   _is_hidden;
 61   bool                   _is_record;
 62   bool                   _has_trusted_loader;
 63 
 64   ciFlags                _flags;
 65 
 66   // Lazy fields get filled in only upon request.
 67   ciInstanceKlass*       _super;
 68   ciInstance*            _java_mirror;
 69 
 70   ciConstantPoolCache*   _field_cache;  // cached map index->field
 71   GrowableArray<ciField*>* _nonstatic_fields;  // ordered by JavaFieldStream
 72   int                    _has_injected_fields; // any non static injected fields? lazily initialized.
 73 
 74   // The possible values of the _implementor fall into following three cases:
 75   //   null: no implementor.
 76   //   A ciInstanceKlass that's not itself: one implementor.
 77   //   Itself: more than one implementor.
 78   ciInstanceKlass*       _implementor;
 79   GrowableArray<ciInstanceKlass*>* _transitive_interfaces;
 80 
 81   void compute_injected_fields();
 82   bool compute_injected_fields_helper();
 83   void compute_transitive_interfaces();
 84 
 85   ciField* get_non_static_field_by_offset(int field_offset);
 86 
 87 protected:
 88   ciInstanceKlass(Klass* k);
 89   ciInstanceKlass(ciSymbol* name, jobject loader);
 90 
 91   InstanceKlass* get_instanceKlass() const {
 92     return InstanceKlass::cast(get_Klass());
 93   }
 94 
 95   oop loader();
 96   jobject loader_handle();
 97 
 98   const char* type_string() { return "ciInstanceKlass"; }
 99 
100   bool is_in_package_impl(const char* packagename, int len);
101 
102   void print_impl(outputStream* st);
103 
104   ciConstantPoolCache* field_cache();
105 
106   bool is_shared() { return _is_shared; }
107 
108   void compute_shared_init_state();
109   bool compute_shared_has_subklass();
110   int  compute_nonstatic_fields();
111   GrowableArray<ciField*>* compute_nonstatic_fields_impl(GrowableArray<ciField*>* super_fields);
112   bool compute_has_trusted_loader();
113 
114   // Update the init_state for shared klasses
115   void update_if_shared(InstanceKlass::ClassState expected) {
116     if (_is_shared && _init_state != expected) {
117       if (is_loaded()) compute_shared_init_state();
118     }
119   }
120 
121 public:
122   // Has this klass been initialized?
123   bool                   is_initialized() {
124     update_if_shared(InstanceKlass::fully_initialized);
125     return _init_state == InstanceKlass::fully_initialized;
126   }
127   bool                   is_not_initialized() {
128     update_if_shared(InstanceKlass::fully_initialized);
129     return _init_state < InstanceKlass::being_initialized;
130   }
131   // Is this klass being initialized?
132   bool                   is_being_initialized() {
133     update_if_shared(InstanceKlass::being_initialized);
134     return _init_state == InstanceKlass::being_initialized;
135   }
136   // Has this klass been linked?
137   bool                   is_linked() {
138     update_if_shared(InstanceKlass::linked);
139     return _init_state >= InstanceKlass::linked;
140   }
141   // Is this klass in error state?
142   bool                   is_in_error_state() {
143     update_if_shared(InstanceKlass::initialization_error);
144     return _init_state == InstanceKlass::initialization_error;
145   }
146 
147   // General klass information.
148   ciFlags                flags()          {
149     assert(is_loaded(), "must be loaded");
150     return _flags;
151   }
152 
153   // Fetch Klass::access_flags.
154   jint                   access_flags() { return flags().as_int(); }
155 
156   bool                   has_finalizer()  {
157     assert(is_loaded(), "must be loaded");
158     return _has_finalizer; }
159   bool                   has_subklass()   {
160     assert(is_loaded(), "must be loaded");
161     // Ignore cached subklass_false case.
162     // It could be invalidated by concurrent class loading and
163     // can result in type paradoxes during compilation when
164     // a subclass is observed, but has_subklass() returns false.
165     if (_has_subklass == subklass_true) {
166       return true;
167     }
168     if (flags().is_final()) {
169       return false;
170     }
171     return compute_shared_has_subklass();
172   }
173 
174   jint                   layout_helper_size_in_bytes()  {
175     return Klass::layout_helper_size_in_bytes(layout_helper());
176   }
177   jint                   size_helper()  {
178     return (Klass::layout_helper_size_in_bytes(layout_helper())
179             >> LogHeapWordSize);
180   }
181   jint                   has_nonstatic_fields()  {
182     assert(is_loaded(), "must be loaded");
183     return _has_nonstatic_fields; }
184   ciInstanceKlass*       super();
185   jint                   nof_implementors() {
186     ciInstanceKlass* impl;
187     assert(is_loaded(), "must be loaded");
188     impl = implementor();
189     if (impl == nullptr) {
190       return 0;
191     } else if (impl != this) {
192       return 1;
193     } else {
194       return 2;
195     }
196   }
197   bool has_nonstatic_concrete_methods()  {
198     assert(is_loaded(), "must be loaded");
199     return _has_nonstatic_concrete_methods;
200   }
201 
202   bool is_hidden() const {
203     return _is_hidden;
204   }
205 
206   bool is_record() const {
207     return _is_record;
208   }
209 
210   ciInstanceKlass* get_canonical_holder(int offset);
211   ciField* get_field_by_offset(int field_offset, bool is_static);
212   ciField* get_field_by_name(ciSymbol* name, ciSymbol* signature, bool is_static);
213   BasicType get_field_type_by_offset(int field_offset, bool is_static);
214 
215   // total number of nonstatic fields (including inherited):
216   int nof_nonstatic_fields() {
217     if (_nonstatic_fields == nullptr)
218       return compute_nonstatic_fields();
219     else
220       return _nonstatic_fields->length();
221   }
222 
223   bool has_injected_fields() {
224     if (_has_injected_fields == -1) {
225       compute_injected_fields();
226     }
227     return _has_injected_fields > 0 ? true : false;
228   }
229 
230   bool has_object_fields() const;
231 
232   // nth nonstatic field (presented by ascending address)
233   ciField* nonstatic_field_at(int i) {
234     assert(_nonstatic_fields != nullptr, "");
235     return _nonstatic_fields->at(i);
236   }
237 
238   ciInstanceKlass* unique_concrete_subklass();
239   bool has_finalizable_subclass();
240 
241   bool has_class_initializer();
242 
243   bool contains_field_offset(int offset);
244 
245   // Get the instance of java.lang.Class corresponding to
246   // this klass.  This instance is used for locking of
247   // synchronized static methods of this klass.
248   ciInstance*            java_mirror();
249 
250   // Java access flags
251   bool is_public      () { return flags().is_public(); }
252   bool is_final       () { return flags().is_final(); }
253   bool is_super       () { return flags().is_super(); }
254   bool is_interface   () { return flags().is_interface(); }
255   bool is_abstract    () { return flags().is_abstract(); }
256 
257   ciMethod* find_method(ciSymbol* name, ciSymbol* signature);
258   // Note:  To find a method from name and type strings, use ciSymbol::make,
259   // but consider adding to vmSymbols.hpp instead.
260 
261   bool is_leaf_type();
262   ciInstanceKlass* implementor();
263 
264   ciInstanceKlass* unique_implementor() {
265     assert(is_loaded(), "must be loaded");
266     assert(is_interface(), "must be");
267     ciInstanceKlass* impl = implementor();
268     return (impl != this ? impl : nullptr);
269   }
270 
271   // Is the defining class loader of this class the default loader?
272   bool uses_default_loader() const;
273 
274   bool is_java_lang_Object() const;
275 
276   BasicType box_klass_type() const;
277   bool is_box_klass() const;
278   bool is_boxed_value_offset(int offset) const;
279 
280   // Is this klass in the given package?
281   bool is_in_package(const char* packagename) {
282     return is_in_package(packagename, (int) strlen(packagename));
283   }
284   bool is_in_package(const char* packagename, int len);
285 
286   // What kind of ciObject is this?
287   bool is_instance_klass() const { return true; }
288 
289   virtual ciKlass* exact_klass() {
290     if (is_loaded() && is_final() && !is_interface()) {
291       return this;
292     }
293     return nullptr;
294   }
295 
296   bool can_be_instantiated() {
297     assert(is_loaded(), "must be loaded");
298     return !is_interface() && !is_abstract();
299   }
300 
301   bool has_trusted_loader() const {
302     return _has_trusted_loader;
303   }
304   GrowableArray<ciInstanceKlass*>* transitive_interfaces() const;
305 
306   // Replay support
307 
308   // Dump the current state of this klass for compilation replay.
309   virtual void dump_replay_data(outputStream* out);
310 
311   static void dump_replay_instanceKlass(outputStream* out, InstanceKlass* ik);
312 
313 
314   // Return stable class name suitable for replay file.
315   const char *replay_name() const;
316 
317 #ifdef ASSERT
318   bool debug_final_field_at(int offset);
319   bool debug_stable_field_at(int offset);
320 #endif
321 };
322 
323 #endif // SHARE_CI_CIINSTANCEKLASS_HPP