1 /*
  2  * Copyright (c) 1999, 2021, 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.
 22  *
 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 
 48 private:
 49   enum SubklassValue { subklass_unknown, subklass_false, subklass_true };
 50 
 51   jobject                _loader;
 52   jobject                _protection_domain;
 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 
 63   ciFlags                _flags;
 64 
 65   // Lazy fields get filled in only upon request.
 66   ciInstanceKlass*       _super;
 67   ciInstance*            _java_mirror;
 68 
 69   ciConstantPoolCache*   _field_cache;  // cached map index->field
 70   GrowableArray<ciField*>* _nonstatic_fields;
 71 
 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 
 80   void compute_injected_fields();
 81   bool compute_injected_fields_helper();
 82 
 83 protected:
 84   ciInstanceKlass(Klass* k);
 85   ciInstanceKlass(ciSymbol* name, jobject loader, jobject protection_domain, BasicType bt = T_OBJECT); // for unloaded klasses
 86 
 87   InstanceKlass* get_instanceKlass() const {
 88     return InstanceKlass::cast(get_Klass());
 89   }
 90 
 91   oop loader();
 92   jobject loader_handle();
 93 
 94   oop protection_domain();
 95   jobject protection_domain_handle();
 96 
 97   const char* type_string() { return "ciInstanceKlass"; }
 98 
 99   bool is_in_package_impl(const char* packagename, int len);
100 
101   void print_impl(outputStream* st);
102 
103   ciConstantPoolCache* field_cache();
104 
105   bool is_shared() { return _is_shared; }
106 
107   void compute_shared_init_state();
108   bool compute_shared_has_subklass();
109   virtual int compute_nonstatic_fields();
110   GrowableArray<ciField*>* compute_nonstatic_fields_impl(GrowableArray<ciField*>* super_fields, bool flatten = true);
111 
112   // Update the init_state for shared klasses
113   void update_if_shared(InstanceKlass::ClassState expected) {
114     if (_is_shared && _init_state != expected) {
115       if (is_loaded()) compute_shared_init_state();
116     }
117   }
118 
119 public:
120   // Has this klass been initialized?
121   bool                   is_initialized() {
122     update_if_shared(InstanceKlass::fully_initialized);
123     return _init_state == InstanceKlass::fully_initialized;
124   }
125   bool                   is_not_initialized() {
126     update_if_shared(InstanceKlass::fully_initialized);
127     return _init_state < InstanceKlass::being_initialized;
128   }
129   // Is this klass being initialized?
130   bool                   is_being_initialized() {
131     update_if_shared(InstanceKlass::being_initialized);
132     return _init_state == InstanceKlass::being_initialized;
133   }
134   // Has this klass been linked?
135   bool                   is_linked() {
136     update_if_shared(InstanceKlass::linked);
137     return _init_state >= InstanceKlass::linked;
138   }
139   // Is this klass in error state?
140   bool                   is_in_error_state() {
141     update_if_shared(InstanceKlass::initialization_error);
142     return _init_state == InstanceKlass::initialization_error;
143   }
144 
145   // General klass information.
146   ciFlags                flags()          {
147     assert(is_loaded(), "must be loaded");
148     return _flags;
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 == NULL) {
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   ciInstanceKlass* get_canonical_holder(int offset);
205   ciField* get_field_by_offset(int field_offset, bool is_static);
206   ciField* get_field_by_name(ciSymbol* name, ciSymbol* signature, bool is_static);
207   // get field descriptor at field_offset ignoring flattening
208   ciField* get_non_flattened_field_by_offset(int field_offset);
209 
210   // total number of nonstatic fields (including inherited):
211   int nof_nonstatic_fields() {
212     if (_nonstatic_fields == NULL) {
213       return compute_nonstatic_fields();
214     } else {
215       return _nonstatic_fields->length();
216     }
217   }
218 
219   bool has_injected_fields() {
220     if (_has_injected_fields == -1) {
221       compute_injected_fields();
222     }
223     return _has_injected_fields > 0 ? true : false;
224   }
225 
226   bool has_object_fields() const;
227 
228   // nth nonstatic field (presented by ascending address)
229   ciField* nonstatic_field_at(int i) {
230     assert(_nonstatic_fields != NULL, "");
231     return _nonstatic_fields->at(i);
232   }
233 
234   ciInstanceKlass* unique_concrete_subklass();
235   bool has_finalizable_subclass();
236 
237   bool contains_field_offset(int offset);
238 
239   // Get the instance of java.lang.Class corresponding to
240   // this klass.  This instance is used for locking of
241   // synchronized static methods of this klass.
242   ciInstance*            java_mirror();
243 
244   // Java access flags
245   bool is_public      () { return flags().is_public(); }
246   bool is_final       () { return flags().is_final(); }
247   bool is_super       () { return flags().is_super(); }
248   bool is_interface   () { return flags().is_interface(); }
249   bool is_abstract    () { return flags().is_abstract(); }
250 
251   ciMethod* find_method(ciSymbol* name, ciSymbol* signature);
252   // Note:  To find a method from name and type strings, use ciSymbol::make,
253   // but consider adding to vmSymbols.hpp instead.
254 
255   bool is_leaf_type();
256   ciInstanceKlass* implementor();
257 
258   ciInstanceKlass* unique_implementor() {
259     assert(is_loaded(), "must be loaded");
260     ciInstanceKlass* impl = implementor();
261     return (impl != this ? impl : NULL);
262   }
263 
264   virtual bool can_be_inline_klass(bool is_exact = false);
265 
266   // Is the defining class loader of this class the default loader?
267   bool uses_default_loader() const;
268 
269   bool is_java_lang_Object() const;
270 
271   BasicType box_klass_type() const;
272   bool is_box_klass() const;
273   bool is_boxed_value_offset(int offset) const;
274   bool is_box_cache_valid() const;
275 
276   // Is this klass in the given package?
277   bool is_in_package(const char* packagename) {
278     return is_in_package(packagename, (int) strlen(packagename));
279   }
280   bool is_in_package(const char* packagename, int len);
281 
282   // What kind of ciObject is this?
283   bool is_instance_klass() const { return true; }
284 
285   virtual ciKlass* exact_klass() {
286     if (is_loaded() && is_final() && !is_interface()) {
287       return this;
288     }
289     return NULL;
290   }
291 
292   bool can_be_instantiated() {
293     assert(is_loaded(), "must be loaded");
294     return !is_interface() && !is_abstract();
295   }
296 
297   // Replay support
298 
299   // Dump the current state of this klass for compilation replay.
300   virtual void dump_replay_data(outputStream* out);
301 
302   static void dump_replay_instanceKlass(outputStream* out, InstanceKlass* ik);
303 
304 
305   // Return stable class name suitable for replay file.
306   const char *replay_name() const;
307 
308 #ifdef ASSERT
309   bool debug_final_field_at(int offset);
310   bool debug_stable_field_at(int offset);
311 #endif
312 };
313 
314 #endif // SHARE_CI_CIINSTANCEKLASS_HPP