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