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.
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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_nonstatic_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   InstanceKlass::ClassState compute_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 public:
116   // Has this klass been initialized?
117   bool                   is_initialized() {
118     InstanceKlass::ClassState state = compute_init_state();
119     return state == InstanceKlass::fully_initialized;
120   }
121   bool                   is_not_initialized() {
122     InstanceKlass::ClassState state = compute_init_state();
123     return state < InstanceKlass::being_initialized;
124   }
125   // Is this klass being initialized?
126   bool                   is_being_initialized() {
127     InstanceKlass::ClassState state = compute_init_state();
128     return state == InstanceKlass::being_initialized;
129   }
130   // Has this klass been linked?
131   bool                   is_linked() {
132     InstanceKlass::ClassState state = compute_init_state();
133     return state >= InstanceKlass::linked;
134   }
135   // Is this klass in error state?
136   bool                   is_in_error_state() {
137     InstanceKlass::ClassState state = compute_init_state();
138     return state == InstanceKlass::initialization_error;
139   }
140 
141   // General klass information.
142   ciFlags                flags()          {
143     assert(is_loaded(), "must be loaded");
144     return _flags;
145   }
146 
147   // Fetch Klass::access_flags.
148   jint                   access_flags() { return flags().as_int(); }
149 
150   bool                   has_finalizer()  {
151     assert(is_loaded(), "must be loaded");
152     return _has_finalizer; }
153   bool                   has_subklass()   {
154     assert(is_loaded(), "must be loaded");
155     // Ignore cached subklass_false case.
156     // It could be invalidated by concurrent class loading and
157     // can result in type paradoxes during compilation when
158     // a subclass is observed, but has_subklass() returns false.
159     if (_has_subklass == subklass_true) {
160       return true;
161     }
162     if (flags().is_final()) {
163       return false;
164     }
165     return compute_shared_has_subklass();
166   }
167 
168   jint                   layout_helper_size_in_bytes()  {
169     return Klass::layout_helper_size_in_bytes(layout_helper());
170   }
171   jint                   size_helper()  {
172     return (Klass::layout_helper_size_in_bytes(layout_helper())
173             >> LogHeapWordSize);
174   }
175   jint                   has_nonstatic_fields()  {
176     assert(is_loaded(), "must be loaded");
177     return _has_nonstatic_fields; }
178   ciInstanceKlass*       super();
179   jint                   nof_implementors() {
180     ciInstanceKlass* impl;
181     assert(is_loaded(), "must be loaded");
182     impl = implementor();
183     if (impl == nullptr) {
184       return 0;
185     } else if (impl != this) {
186       return 1;
187     } else {
188       return 2;
189     }
190   }
191   bool has_nonstatic_concrete_methods()  {
192     assert(is_loaded(), "must be loaded");
193     return _has_nonstatic_concrete_methods;
194   }
195 
196   bool is_hidden() const {
197     return _is_hidden;
198   }
199 
200   bool is_record() const {
201     return _is_record;
202   }
203 
204   bool trust_final_fields() const {
205     return _trust_final_fields;
206   }
207 
208   ciInstanceKlass* get_canonical_holder(int offset);
209   ciField* get_field_by_offset(int field_offset, bool is_static);
210   ciField* get_field_by_name(ciSymbol* name, ciSymbol* signature, bool is_static);
211   BasicType get_field_type_by_offset(int field_offset, bool is_static);
212 
213   // total number of nonstatic fields (including inherited):
214   int nof_nonstatic_fields() {
215     if (_nonstatic_fields == nullptr)
216       return compute_nonstatic_fields();
217     else
218       return _nonstatic_fields->length();
219   }
220 
221   bool has_injected_fields() {
222     if (_has_injected_fields == -1) {
223       compute_injected_fields();
224     }
225     return _has_injected_fields > 0 ? true : false;
226   }
227 
228   bool has_object_fields() const;
229 
230   // nth nonstatic field (presented by ascending address)
231   ciField* nonstatic_field_at(int i) {
232     assert(_nonstatic_fields != nullptr, "");
233     return _nonstatic_fields->at(i);
234   }
235 
236   ciInstanceKlass* unique_concrete_subklass();
237   bool has_finalizable_subclass();
238 
239   bool has_class_initializer();
240 
241   bool contains_field_offset(int offset);
242 
243   // Get the instance of java.lang.Class corresponding to
244   // this klass.  This instance is used for locking of
245   // synchronized static methods of this klass.
246   ciInstance*            java_mirror();
247 
248   // Java access flags
249   bool is_public      () { return flags().is_public(); }
250   bool is_final       () { return flags().is_final(); }
251   bool is_super       () { return flags().is_super(); }
252   bool is_interface   () { return flags().is_interface(); }
253   bool is_abstract    () { return flags().is_abstract(); }
254 
255   ciMethod* find_method(ciSymbol* name, ciSymbol* signature);
256   // Note:  To find a method from name and type strings, use ciSymbol::make,
257   // but consider adding to vmSymbols.hpp instead.
258 
259   bool is_leaf_type();
260   ciInstanceKlass* implementor();
261 
262   ciInstanceKlass* unique_implementor() {
263     assert(is_loaded(), "must be loaded");
264     assert(is_interface(), "must be");
265     ciInstanceKlass* impl = implementor();
266     return (impl != this ? impl : nullptr);
267   }
268 
269   // Is the defining class loader of this class the default loader?
270   bool uses_default_loader() const;
271 
272   bool is_java_lang_Object() const;
273 
274   BasicType box_klass_type() const;
275   bool is_box_klass() const;
276   bool is_boxed_value_offset(int offset) const;
277 
278   // Is this klass in the given package?
279   bool is_in_package(const char* packagename) {
280     return is_in_package(packagename, (int) strlen(packagename));
281   }
282   bool is_in_package(const char* packagename, int len);
283 
284   // What kind of ciObject is this?
285   bool is_instance_klass() const { return true; }
286 
287   virtual ciKlass* exact_klass() {
288     if (is_loaded() && is_final() && !is_interface()) {
289       return this;
290     }
291     return nullptr;
292   }
293 
294   bool can_be_instantiated() {
295     assert(is_loaded(), "must be loaded");
296     return !is_interface() && !is_abstract();
297   }
298 
299   bool has_trusted_loader() const {
300     return _has_trusted_loader;
301   }
302   GrowableArray<ciInstanceKlass*>* transitive_interfaces() const;
303 
304   // Replay support
305 
306   // Dump the current state of this klass for compilation replay.
307   virtual void dump_replay_data(outputStream* out);
308 
309   static void dump_replay_instanceKlass(outputStream* out, InstanceKlass* ik);
310 
311 
312   // Return stable class name suitable for replay file.
313   const char *replay_name() const;
314 
315 #ifdef ASSERT
316   bool debug_final_field_at(int offset);
317   bool debug_stable_field_at(int offset);
318 #endif
319 };
320 
321 #endif // SHARE_CI_CIINSTANCEKLASS_HPP