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 
 73   // Fields declared in the bytecode (without nested fields in flat fields),
 74   // ordered in JavaFieldStream order, with superclasses first (i.e. from lang.java.Object
 75   // to most derived class).
 76   const GrowableArray<ciField*>* _declared_nonstatic_fields;
 77 
 78   // Fields laid out in memory (flat fields are expanded into their components). The ciField object
 79   // for each primitive component has the holder being this ciInstanceKlass or one of its
 80   // superclasses.
 81   // Fields are in the same order as in _declared_nonstatic_fields, but flat fields are replaced by
 82   // the list of their own fields, ordered the same way (hierarchy traversed top-down, in
 83   // JavaFieldStream order).
 84   const GrowableArray<ciField*>* _nonstatic_fields;
 85 
 86   int                    _has_injected_fields; // any non static injected fields? lazily initialized.
 87 
 88   // The possible values of the _implementor fall into following three cases:
 89   //   null: no implementor.
 90   //   A ciInstanceKlass that's not itself: one implementor.
 91   //   Itself: more than one implementor.
 92   ciInstanceKlass*       _implementor;
 93   GrowableArray<ciInstanceKlass*>* _transitive_interfaces;
 94 
 95   void compute_injected_fields();
 96   bool compute_injected_fields_helper();
 97   void compute_transitive_interfaces();
 98 
 99   ciField* get_non_static_field_by_offset(int field_offset);
100 
101 protected:
102   ciInstanceKlass(Klass* k);
103   ciInstanceKlass(ciSymbol* name, jobject loader, BasicType bt = T_OBJECT); // for unloaded klasses
104 
105   InstanceKlass* get_instanceKlass() const {
106     return InstanceKlass::cast(get_Klass());
107   }
108 
109   oop loader();
110   jobject loader_handle();
111 
112   const char* type_string() { return "ciInstanceKlass"; }
113 
114   bool is_in_package_impl(const char* packagename, int len);
115 
116   void print_impl(outputStream* st);
117 
118   ciConstantPoolCache* field_cache();
119 
120   bool is_shared() { return _is_shared; }
121 
122   void compute_shared_init_state();
123   bool compute_shared_has_subklass();
124   void compute_nonstatic_fields();
125   void compute_nonstatic_fields_impl(const GrowableArray<ciField*>* super_declared_fields, const GrowableArray<ciField*>* super_fields);
126   bool compute_has_trusted_loader();
127 
128   // Update the init_state for shared klasses
129   void update_if_shared(InstanceKlass::ClassState expected) {
130     if (_is_shared && _init_state != expected) {
131       if (is_loaded()) compute_shared_init_state();
132     }
133   }
134 
135 public:
136   // Has this klass been initialized?
137   bool                   is_initialized() {
138     update_if_shared(InstanceKlass::fully_initialized);
139     return _init_state == InstanceKlass::fully_initialized;
140   }
141   bool                   is_not_initialized() {
142     update_if_shared(InstanceKlass::fully_initialized);
143     return _init_state < InstanceKlass::being_initialized;
144   }
145   // Is this klass being initialized?
146   bool                   is_being_initialized() {
147     update_if_shared(InstanceKlass::being_initialized);
148     return _init_state == InstanceKlass::being_initialized;
149   }
150   // Has this klass been linked?
151   bool                   is_linked() {
152     update_if_shared(InstanceKlass::linked);
153     return _init_state >= InstanceKlass::linked;
154   }
155   // Is this klass in error state?
156   bool                   is_in_error_state() {
157     update_if_shared(InstanceKlass::initialization_error);
158     return _init_state == InstanceKlass::initialization_error;
159   }
160 
161   // General klass information.
162   ciFlags                flags()          {
163     assert(is_loaded(), "must be loaded");
164     return _flags;
165   }
166 
167   // Fetch Klass::access_flags.
168   jint                   access_flags() { return flags().as_int(); }
169 
170   bool                   has_finalizer()  {
171     assert(is_loaded(), "must be loaded");
172     return _has_finalizer; }
173   bool                   has_subklass()   {
174     assert(is_loaded(), "must be loaded");
175     // Ignore cached subklass_false case.
176     // It could be invalidated by concurrent class loading and
177     // can result in type paradoxes during compilation when
178     // a subclass is observed, but has_subklass() returns false.
179     if (_has_subklass == subklass_true) {
180       return true;
181     }
182     if (flags().is_final()) {
183       return false;
184     }
185     return compute_shared_has_subklass();
186   }
187 
188   jint                   layout_helper_size_in_bytes()  {
189     return Klass::layout_helper_size_in_bytes(layout_helper());
190   }
191   jint                   size_helper()  {
192     return (Klass::layout_helper_size_in_bytes(layout_helper())
193             >> LogHeapWordSize);
194   }
195   jint                   has_nonstatic_fields()  {
196     assert(is_loaded(), "must be loaded");
197     return _has_nonstatic_fields; }
198   ciInstanceKlass*       super();
199   jint                   nof_implementors() {
200     ciInstanceKlass* impl;
201     assert(is_loaded(), "must be loaded");
202     impl = implementor();
203     if (impl == nullptr) {
204       return 0;
205     } else if (impl != this) {
206       return 1;
207     } else {
208       return 2;
209     }
210   }
211   bool has_nonstatic_concrete_methods()  {
212     assert(is_loaded(), "must be loaded");
213     return _has_nonstatic_concrete_methods;
214   }
215 
216   bool is_hidden() const {
217     return _is_hidden;
218   }
219 
220   bool is_record() const {
221     return _is_record;
222   }
223 
224   bool trust_final_fields() const {
225     return _trust_final_fields;
226   }
227 
228   ciInstanceKlass* get_canonical_holder(int offset);
229   ciField* get_field_by_offset(int field_offset, bool is_static);
230   ciField* get_field_by_name(ciSymbol* name, ciSymbol* signature, bool is_static);
231   // Get field descriptor at field_offset ignoring flattening
232   ciField* get_non_flat_field_by_offset(int field_offset);
233   // Get the index of the declared field that contains this offset
234   int field_index_by_offset(int offset);
235 
236   // Total number of nonstatic fields (including inherited)
237   int nof_declared_nonstatic_fields() {
238     if (_declared_nonstatic_fields == nullptr) {
239       compute_nonstatic_fields();
240     }
241     return _declared_nonstatic_fields->length();
242   }
243   BasicType get_field_type_by_offset(int field_offset, bool is_static);
244 
245   int nof_nonstatic_fields() {
246     if (_nonstatic_fields == nullptr) {
247       compute_nonstatic_fields();
248     }
249     return _nonstatic_fields->length();
250   }
251 
252   bool has_injected_fields() {
253     if (_has_injected_fields == -1) {
254       compute_injected_fields();
255     }
256     return _has_injected_fields > 0 ? true : false;
257   }
258 
259   bool has_object_fields() const;
260 
261   ciField* declared_nonstatic_field_at(int i) {
262     assert(_declared_nonstatic_fields != nullptr, "should be initialized");
263     return _declared_nonstatic_fields->at(i);
264   }
265 
266   ciField* nonstatic_field_at(int i) {
267     assert(_nonstatic_fields != nullptr, "");
268     return _nonstatic_fields->at(i);
269   }
270 
271   ciInstanceKlass* unique_concrete_subklass();
272   bool has_finalizable_subclass();
273 
274   bool has_class_initializer();
275 
276   bool contains_field_offset(int offset);
277 
278   // Get the instance of java.lang.Class corresponding to
279   // this klass.  This instance is used for locking of
280   // synchronized static methods of this klass.
281   ciInstance*            java_mirror();
282 
283   // Java access flags
284   bool is_public      () { return flags().is_public(); }
285   bool is_final       () { return flags().is_final(); }
286   bool is_interface   () { return flags().is_interface(); }
287   bool is_abstract    () { return flags().is_abstract(); }
288   bool is_abstract_value_klass() { return is_abstract() && !flags().is_identity(); }
289 
290   ciMethod* find_method(ciSymbol* name, ciSymbol* signature);
291   // Note:  To find a method from name and type strings, use ciSymbol::make,
292   // but consider adding to vmSymbols.hpp instead.
293 
294   bool is_leaf_type();
295   ciInstanceKlass* implementor();
296 
297   ciInstanceKlass* unique_implementor() {
298     assert(is_loaded(), "must be loaded");
299     assert(is_interface(), "must be");
300     ciInstanceKlass* impl = implementor();
301     return (impl != this ? impl : nullptr);
302   }
303 
304   virtual bool can_be_inline_klass(bool is_exact = false);
305 
306   // Is the defining class loader of this class the default loader?
307   bool uses_default_loader() const;
308 
309   bool is_java_lang_Object() const;
310 
311   BasicType box_klass_type() const;
312   bool is_box_klass() const;
313   bool is_boxed_value_offset(int offset) const;
314 
315   // Is this klass in the given package?
316   bool is_in_package(const char* packagename) {
317     return is_in_package(packagename, (int) strlen(packagename));
318   }
319   bool is_in_package(const char* packagename, int len);
320 
321   // What kind of ciObject is this?
322   bool is_instance_klass() const { return true; }
323 
324   virtual ciKlass* exact_klass() {
325     if (is_loaded() && is_final() && !is_interface()) {
326       return this;
327     }
328     return nullptr;
329   }
330 
331   bool can_be_instantiated() {
332     assert(is_loaded(), "must be loaded");
333     return !is_interface() && !is_abstract();
334   }
335 
336   bool has_trusted_loader() const {
337     return _has_trusted_loader;
338   }
339   GrowableArray<ciInstanceKlass*>* transitive_interfaces() const;
340 
341   // Replay support
342 
343   // Dump the current state of this klass for compilation replay.
344   virtual void dump_replay_data(outputStream* out);
345 
346   static void dump_replay_instanceKlass(outputStream* out, InstanceKlass* ik);
347 
348 
349   // Return stable class name suitable for replay file.
350   const char *replay_name() const;
351 
352 #ifdef ASSERT
353   bool debug_final_field_at(int offset);
354   bool debug_stable_field_at(int offset);
355 #endif
356 };
357 
358 #endif // SHARE_CI_CIINSTANCEKLASS_HPP