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                   _trust_final_fields;
 63   bool                   _has_trusted_loader;
 64 
 65   ciFlags                _flags;
 66 
 67   // Lazy fields get filled in only upon request.
 68   ciInstanceKlass*       _super;
 69   ciInstance*            _java_mirror;
 70 
 71   ciConstantPoolCache*   _field_cache;  // cached map index->field
 72   GrowableArray<ciField*>* _nonstatic_fields;  // ordered by JavaFieldStream
 73   int                    _has_injected_fields; // any non static injected fields? lazily initialized.
 74 
 75   // The possible values of the _implementor fall into following three cases:
 76   //   null: no implementor.
 77   //   A ciInstanceKlass that's not itself: one implementor.
 78   //   Itself: more than one implementor.
 79   ciInstanceKlass*       _implementor;
 80   GrowableArray<ciInstanceKlass*>* _transitive_interfaces;
 81 
 82   void compute_injected_fields();
 83   bool compute_injected_fields_helper();
 84   void compute_transitive_interfaces();
 85 
 86   ciField* get_non_static_field_by_offset(int field_offset);
 87 
 88 protected:
 89   ciInstanceKlass(Klass* k);
 90   ciInstanceKlass(ciSymbol* name, jobject loader);
 91 
 92   InstanceKlass* get_instanceKlass() const {
 93     return InstanceKlass::cast(get_Klass());
 94   }
 95 
 96   oop loader();
 97   jobject loader_handle();
 98 
 99   const char* type_string() { return "ciInstanceKlass"; }
100 
101   bool is_in_package_impl(const char* packagename, int len);
102 
103   void print_impl(outputStream* st);
104 
105   ciConstantPoolCache* field_cache();
106 
107   bool is_shared() { return _is_shared; }
108 
109   void compute_shared_init_state();
110   bool compute_shared_has_subklass();
111   int  compute_nonstatic_fields();
112   GrowableArray<ciField*>* compute_nonstatic_fields_impl(GrowableArray<ciField*>* super_fields);
113   bool compute_has_trusted_loader();
114 
115   // Update the init_state for shared klasses
116   void update_if_shared(InstanceKlass::ClassState expected) {
117     if (_is_shared && _init_state != expected) {
118       if (is_loaded()) compute_shared_init_state();
119     }
120   }
121 
122   static InstanceKlass::ClassState compute_init_state(InstanceKlass* ik);
123 
124 public:
125   // Has this klass been initialized?
126   bool                   is_initialized() {
127     update_if_shared(InstanceKlass::fully_initialized);
128     return _init_state == InstanceKlass::fully_initialized;
129   }
130   bool                   is_not_initialized() {
131     update_if_shared(InstanceKlass::fully_initialized);
132     return _init_state < InstanceKlass::being_initialized;
133   }
134   // Is this klass being initialized?
135   bool                   is_being_initialized() {
136     update_if_shared(InstanceKlass::being_initialized);
137     return _init_state == InstanceKlass::being_initialized;
138   }
139   // Has this klass been linked?
140   bool                   is_linked() {
141     update_if_shared(InstanceKlass::linked);
142     return _init_state >= InstanceKlass::linked;
143   }
144   // Is this klass in error state?
145   bool                   is_in_error_state() {
146     update_if_shared(InstanceKlass::initialization_error);
147     return _init_state == InstanceKlass::initialization_error;
148   }
149 
150   // General klass information.
151   ciFlags                flags()          {
152     assert(is_loaded(), "must be loaded");
153     return _flags;
154   }
155 
156   // Fetch Klass::access_flags.
157   jint                   access_flags() { return flags().as_int(); }
158 
159   bool                   has_finalizer()  {
160     assert(is_loaded(), "must be loaded");
161     return _has_finalizer; }
162   bool                   has_subklass()   {
163     assert(is_loaded(), "must be loaded");
164     // Ignore cached subklass_false case.
165     // It could be invalidated by concurrent class loading and
166     // can result in type paradoxes during compilation when
167     // a subclass is observed, but has_subklass() returns false.
168     if (_has_subklass == subklass_true) {
169       return true;
170     }
171     if (flags().is_final()) {
172       return false;
173     }
174     return compute_shared_has_subklass();
175   }
176 
177   jint                   layout_helper_size_in_bytes()  {
178     return Klass::layout_helper_size_in_bytes(layout_helper());
179   }
180   jint                   size_helper()  {
181     return (Klass::layout_helper_size_in_bytes(layout_helper())
182             >> LogHeapWordSize);
183   }
184   jint                   has_nonstatic_fields()  {
185     assert(is_loaded(), "must be loaded");
186     return _has_nonstatic_fields; }
187   ciInstanceKlass*       super();
188   jint                   nof_implementors() {
189     ciInstanceKlass* impl;
190     assert(is_loaded(), "must be loaded");
191     impl = implementor();
192     if (impl == nullptr) {
193       return 0;
194     } else if (impl != this) {
195       return 1;
196     } else {
197       return 2;
198     }
199   }
200   bool has_nonstatic_concrete_methods()  {
201     assert(is_loaded(), "must be loaded");
202     return _has_nonstatic_concrete_methods;
203   }
204 
205   bool is_hidden() const {
206     return _is_hidden;
207   }
208 
209   bool is_record() const {
210     return _is_record;
211   }
212 
213   bool trust_final_fields() const {
214     return _trust_final_fields;
215   }
216 
217   ciInstanceKlass* get_canonical_holder(int offset);
218   ciField* get_field_by_offset(int field_offset, bool is_static);
219   ciField* get_field_by_name(ciSymbol* name, ciSymbol* signature, bool is_static);
220   BasicType get_field_type_by_offset(int field_offset, bool is_static);
221 
222   // total number of nonstatic fields (including inherited):
223   int nof_nonstatic_fields() {
224     if (_nonstatic_fields == nullptr)
225       return compute_nonstatic_fields();
226     else
227       return _nonstatic_fields->length();
228   }
229 
230   bool has_injected_fields() {
231     if (_has_injected_fields == -1) {
232       compute_injected_fields();
233     }
234     return _has_injected_fields > 0 ? true : false;
235   }
236 
237   bool has_object_fields() const;
238 
239   // nth nonstatic field (presented by ascending address)
240   ciField* nonstatic_field_at(int i) {
241     assert(_nonstatic_fields != nullptr, "");
242     return _nonstatic_fields->at(i);
243   }
244 
245   ciInstanceKlass* unique_concrete_subklass();
246   bool has_finalizable_subclass();
247 
248   bool has_class_initializer();
249 
250   bool contains_field_offset(int offset);
251 
252   // Get the instance of java.lang.Class corresponding to
253   // this klass.  This instance is used for locking of
254   // synchronized static methods of this klass.
255   ciInstance*            java_mirror();
256 
257   // Java access flags
258   bool is_public      () { return flags().is_public(); }
259   bool is_final       () { return flags().is_final(); }
260   bool is_super       () { return flags().is_super(); }
261   bool is_interface   () { return flags().is_interface(); }
262   bool is_abstract    () { return flags().is_abstract(); }
263 
264   ciMethod* find_method(ciSymbol* name, ciSymbol* signature);
265   // Note:  To find a method from name and type strings, use ciSymbol::make,
266   // but consider adding to vmSymbols.hpp instead.
267 
268   bool is_leaf_type();
269   ciInstanceKlass* implementor();
270 
271   ciInstanceKlass* unique_implementor() {
272     assert(is_loaded(), "must be loaded");
273     assert(is_interface(), "must be");
274     ciInstanceKlass* impl = implementor();
275     return (impl != this ? impl : nullptr);
276   }
277 
278   // Is the defining class loader of this class the default loader?
279   bool uses_default_loader() const;
280 
281   bool is_java_lang_Object() const;
282 
283   BasicType box_klass_type() const;
284   bool is_box_klass() const;
285   bool is_boxed_value_offset(int offset) const;
286 
287   // Is this klass in the given package?
288   bool is_in_package(const char* packagename) {
289     return is_in_package(packagename, (int) strlen(packagename));
290   }
291   bool is_in_package(const char* packagename, int len);
292 
293   // What kind of ciObject is this?
294   bool is_instance_klass() const { return true; }
295 
296   virtual ciKlass* exact_klass() {
297     if (is_loaded() && is_final() && !is_interface()) {
298       return this;
299     }
300     return nullptr;
301   }
302 
303   bool can_be_instantiated() {
304     assert(is_loaded(), "must be loaded");
305     return !is_interface() && !is_abstract();
306   }
307 
308   bool has_trusted_loader() const {
309     return _has_trusted_loader;
310   }
311   GrowableArray<ciInstanceKlass*>* transitive_interfaces() const;
312 
313   // Replay support
314 
315   // Dump the current state of this klass for compilation replay.
316   virtual void dump_replay_data(outputStream* out);
317 
318   static void dump_replay_instanceKlass(outputStream* out, InstanceKlass* ik);
319 
320 
321   // Return stable class name suitable for replay file.
322   const char *replay_name() const;
323 
324 #ifdef ASSERT
325   bool debug_final_field_at(int offset);
326   bool debug_stable_field_at(int offset);
327 #endif
328 };
329 
330 #endif // SHARE_CI_CIINSTANCEKLASS_HPP