1 /*
  2  * Copyright (c) 1997, 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.
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 23  */
 24 
 25 #ifndef SHARE_UTILITIES_ACCESSFLAGS_HPP
 26 #define SHARE_UTILITIES_ACCESSFLAGS_HPP
 27 
 28 #include "jvm_constants.h"
 29 #include "utilities/debug.hpp"
 30 #include "utilities/globalDefinitions.hpp"
 31 #include "utilities/macros.hpp"
 32 
 33 // AccessFlags is an abstraction over Java access flags.
 34 
 35 class outputStream;
 36 
 37 enum {
 38   // See jvm.h for shared JVM_ACC_XXX access flags
 39 
 40   // HotSpot-specific access flags
 41 
 42   // flags actually put in .class file
 43   JVM_ACC_WRITTEN_FLAGS           = 0x00007FFF,
 44 
 45   // Method* flags
 46   JVM_ACC_MONITOR_MATCH           = 0x10000000,     // True if we know that monitorenter/monitorexit bytecodes match
 47   JVM_ACC_HAS_MONITOR_BYTECODES   = 0x20000000,     // Method contains monitorenter/monitorexit bytecodes
 48   JVM_ACC_HAS_LOOPS               = 0x40000000,     // Method has loops
 49   JVM_ACC_LOOPS_FLAG_INIT         = (int)0x80000000,// The loop flag has been initialized
 50   JVM_ACC_QUEUED                  = 0x01000000,     // Queued for compilation
 51   JVM_ACC_NOT_C2_COMPILABLE       = 0x02000000,
 52   JVM_ACC_NOT_C1_COMPILABLE       = 0x04000000,
 53   JVM_ACC_NOT_C2_OSR_COMPILABLE   = 0x08000000,
 54   JVM_ACC_HAS_LINE_NUMBER_TABLE   = 0x00100000,
 55   JVM_ACC_HAS_CHECKED_EXCEPTIONS  = 0x00400000,
 56   JVM_ACC_HAS_JSRS                = 0x00800000,
 57   JVM_ACC_IS_OLD                  = 0x00010000,     // RedefineClasses() has replaced this method
 58   JVM_ACC_IS_OBSOLETE             = 0x00020000,     // RedefineClasses() has made method obsolete
 59   JVM_ACC_IS_PREFIXED_NATIVE      = 0x00040000,     // JVMTI has prefixed this native method
 60   JVM_ACC_ON_STACK                = 0x00080000,     // RedefineClasses() was used on the stack
 61   JVM_ACC_IS_DELETED              = 0x00008000,     // RedefineClasses() has deleted this method
 62 
 63   // Klass* flags
 64   JVM_ACC_HAS_MIRANDA_METHODS     = 0x10000000,     // True if this class has miranda methods in it's vtable
 65   JVM_ACC_HAS_VANILLA_CONSTRUCTOR = 0x20000000,     // True if klass has a vanilla default constructor
 66   JVM_ACC_HAS_FINALIZER           = 0x40000000,     // True if klass has a non-empty finalize() method
 67   JVM_ACC_IS_CLONEABLE_FAST       = (int)0x80000000,// True if klass implements the Cloneable interface and can be optimized in generated code
 68   JVM_ACC_HAS_FINAL_METHOD        = 0x01000000,     // True if klass has final method
 69   JVM_ACC_IS_SHARED_CLASS         = 0x02000000,     // True if klass is shared
 70   JVM_ACC_IS_HIDDEN_CLASS         = 0x04000000,     // True if klass is hidden
 71   JVM_ACC_IS_VALUE_BASED_CLASS    = 0x08000000,     // True if klass is marked as a ValueBased class
 72   JVM_ACC_IS_BEING_REDEFINED      = 0x00100000,     // True if the klass is being redefined.
 73   JVM_ACC_HAS_RESOLVED_METHODS    = 0x00200000,     // True if the klass has resolved methods
 74 
 75   // Klass* and Method* flags
 76   JVM_ACC_HAS_LOCAL_VARIABLE_TABLE= 0x00400000,
 77 
 78   JVM_ACC_PROMOTED_FLAGS          = 0x00400000,     // flags promoted from methods to the holding klass
 79 
 80   // field flags
 81   // Note: these flags must be defined in the low order 16 bits because
 82   // InstanceKlass only stores a ushort worth of information from the
 83   // AccessFlags value.
 84   // These bits must not conflict with any other field-related access flags
 85   // (e.g., ACC_ENUM).
 86   // Note that the class-related ACC_ANNOTATION bit conflicts with these flags.
 87   JVM_ACC_FIELD_ACCESS_WATCHED            = 0x00002000, // field access is watched by JVMTI
 88   JVM_ACC_FIELD_MODIFICATION_WATCHED      = 0x00008000, // field modification is watched by JVMTI
 89   JVM_ACC_FIELD_INTERNAL                  = 0x00000400, // internal field, same as JVM_ACC_ABSTRACT
 90   JVM_ACC_FIELD_STABLE                    = 0x00000020, // @Stable field, same as JVM_ACC_SYNCHRONIZED and JVM_ACC_SUPER
 91   JVM_ACC_FIELD_INITIALIZED_FINAL_UPDATE  = 0x00000100, // (static) final field updated outside (class) initializer, same as JVM_ACC_NATIVE
 92   JVM_ACC_FIELD_HAS_GENERIC_SIGNATURE     = 0x00000800, // field has generic signature
 93 
 94   JVM_ACC_FIELD_INTERNAL_FLAGS       = JVM_ACC_FIELD_ACCESS_WATCHED |
 95                                        JVM_ACC_FIELD_MODIFICATION_WATCHED |
 96                                        JVM_ACC_FIELD_INTERNAL |
 97                                        JVM_ACC_FIELD_STABLE |
 98                                        JVM_ACC_FIELD_HAS_GENERIC_SIGNATURE,
 99 
100                                                     // flags accepted by set_field_flags()
101   JVM_ACC_FIELD_FLAGS                = JVM_RECOGNIZED_FIELD_MODIFIERS | JVM_ACC_FIELD_INTERNAL_FLAGS
102 
103 };
104 
105 
106 class AccessFlags {
107   friend class VMStructs;
108  private:
109   jint _flags;
110 
111  public:
112   AccessFlags() : _flags(0) {}
113   explicit AccessFlags(jint flags) : _flags(flags) {}
114 
115   // Java access flags
116   bool is_public      () const         { return (_flags & JVM_ACC_PUBLIC      ) != 0; }
117   bool is_private     () const         { return (_flags & JVM_ACC_PRIVATE     ) != 0; }
118   bool is_protected   () const         { return (_flags & JVM_ACC_PROTECTED   ) != 0; }
119   bool is_static      () const         { return (_flags & JVM_ACC_STATIC      ) != 0; }
120   bool is_final       () const         { return (_flags & JVM_ACC_FINAL       ) != 0; }
121   bool is_synchronized() const         { return (_flags & JVM_ACC_SYNCHRONIZED) != 0; }
122   bool is_super       () const         { return (_flags & JVM_ACC_SUPER       ) != 0; }
123   bool is_volatile    () const         { return (_flags & JVM_ACC_VOLATILE    ) != 0; }
124   bool is_transient   () const         { return (_flags & JVM_ACC_TRANSIENT   ) != 0; }
125   bool is_native      () const         { return (_flags & JVM_ACC_NATIVE      ) != 0; }
126   bool is_interface   () const         { return (_flags & JVM_ACC_INTERFACE   ) != 0; }
127   bool is_abstract    () const         { return (_flags & JVM_ACC_ABSTRACT    ) != 0; }
128 
129   // Attribute flags
130   bool is_synthetic   () const         { return (_flags & JVM_ACC_SYNTHETIC   ) != 0; }
131 
132   // Method* flags
133   bool is_monitor_matching     () const { return (_flags & JVM_ACC_MONITOR_MATCH          ) != 0; }
134   bool has_monitor_bytecodes   () const { return (_flags & JVM_ACC_HAS_MONITOR_BYTECODES  ) != 0; }
135   bool has_loops               () const { return (_flags & JVM_ACC_HAS_LOOPS              ) != 0; }
136   bool loops_flag_init         () const { return (_flags & JVM_ACC_LOOPS_FLAG_INIT        ) != 0; }
137   bool queued_for_compilation  () const { return (_flags & JVM_ACC_QUEUED                 ) != 0; }
138   bool is_not_c1_compilable    () const { return (_flags & JVM_ACC_NOT_C1_COMPILABLE      ) != 0; }
139   bool is_not_c2_compilable    () const { return (_flags & JVM_ACC_NOT_C2_COMPILABLE      ) != 0; }
140   bool is_not_c2_osr_compilable() const { return (_flags & JVM_ACC_NOT_C2_OSR_COMPILABLE  ) != 0; }
141   bool has_linenumber_table    () const { return (_flags & JVM_ACC_HAS_LINE_NUMBER_TABLE  ) != 0; }
142   bool has_checked_exceptions  () const { return (_flags & JVM_ACC_HAS_CHECKED_EXCEPTIONS ) != 0; }
143   bool has_jsrs                () const { return (_flags & JVM_ACC_HAS_JSRS               ) != 0; }
144   bool is_old                  () const { return (_flags & JVM_ACC_IS_OLD                 ) != 0; }
145   bool is_obsolete             () const { return (_flags & JVM_ACC_IS_OBSOLETE            ) != 0; }
146   bool is_deleted              () const { return (_flags & JVM_ACC_IS_DELETED             ) != 0; }
147   bool is_prefixed_native      () const { return (_flags & JVM_ACC_IS_PREFIXED_NATIVE     ) != 0; }
148 
149   // Klass* flags
150   bool has_miranda_methods     () const { return (_flags & JVM_ACC_HAS_MIRANDA_METHODS    ) != 0; }
151   bool has_vanilla_constructor () const { return (_flags & JVM_ACC_HAS_VANILLA_CONSTRUCTOR) != 0; }
152   bool has_finalizer           () const { return (_flags & JVM_ACC_HAS_FINALIZER          ) != 0; }
153   bool has_final_method        () const { return (_flags & JVM_ACC_HAS_FINAL_METHOD       ) != 0; }
154   bool is_cloneable_fast       () const { return (_flags & JVM_ACC_IS_CLONEABLE_FAST      ) != 0; }
155   bool is_shared_class         () const { return (_flags & JVM_ACC_IS_SHARED_CLASS        ) != 0; }
156   bool is_hidden_class         () const { return (_flags & JVM_ACC_IS_HIDDEN_CLASS        ) != 0; }
157   bool is_value_based_class    () const { return (_flags & JVM_ACC_IS_VALUE_BASED_CLASS   ) != 0; }
158 
159   // Klass* and Method* flags
160   bool has_localvariable_table () const { return (_flags & JVM_ACC_HAS_LOCAL_VARIABLE_TABLE) != 0; }
161   void set_has_localvariable_table()    { atomic_set_bits(JVM_ACC_HAS_LOCAL_VARIABLE_TABLE); }
162   void clear_has_localvariable_table()  { atomic_clear_bits(JVM_ACC_HAS_LOCAL_VARIABLE_TABLE); }
163 
164   bool is_being_redefined() const       { return (_flags & JVM_ACC_IS_BEING_REDEFINED) != 0; }
165   void set_is_being_redefined()         { atomic_set_bits(JVM_ACC_IS_BEING_REDEFINED); }
166   void clear_is_being_redefined()       { atomic_clear_bits(JVM_ACC_IS_BEING_REDEFINED); }
167 
168   bool has_resolved_methods() const     { return (_flags & JVM_ACC_HAS_RESOLVED_METHODS) != 0; }
169   void set_has_resolved_methods()       { atomic_set_bits(JVM_ACC_HAS_RESOLVED_METHODS); }
170 
171   // field flags
172   bool is_field_access_watched() const  { return (_flags & JVM_ACC_FIELD_ACCESS_WATCHED) != 0; }
173   bool is_field_modification_watched() const
174                                         { return (_flags & JVM_ACC_FIELD_MODIFICATION_WATCHED) != 0; }
175   bool has_field_initialized_final_update() const
176                                         { return (_flags & JVM_ACC_FIELD_INITIALIZED_FINAL_UPDATE) != 0; }
177   bool on_stack() const                 { return (_flags & JVM_ACC_ON_STACK) != 0; }
178   bool is_internal() const              { return (_flags & JVM_ACC_FIELD_INTERNAL) != 0; }
179   bool is_stable() const                { return (_flags & JVM_ACC_FIELD_STABLE) != 0; }
180   bool field_has_generic_signature() const
181                                         { return (_flags & JVM_ACC_FIELD_HAS_GENERIC_SIGNATURE) != 0; }
182 
183   // get .class file flags
184   jint get_flags               () const { return (_flags & JVM_ACC_WRITTEN_FLAGS); }
185 
186   // Initialization
187   void add_promoted_flags(jint flags)   { _flags |= (flags & JVM_ACC_PROMOTED_FLAGS); }
188   void set_field_flags(jint flags)      {
189     assert((flags & JVM_ACC_FIELD_FLAGS) == flags, "only recognized flags");
190     _flags = (flags & JVM_ACC_FIELD_FLAGS);
191   }
192   void set_flags(jint flags)            { _flags = (flags & JVM_ACC_WRITTEN_FLAGS); }
193 
194   void set_queued_for_compilation()    { atomic_set_bits(JVM_ACC_QUEUED); }
195   void clear_queued_for_compilation()  { atomic_clear_bits(JVM_ACC_QUEUED); }
196 
197   // Atomic update of flags
198   void atomic_set_bits(jint bits);
199   void atomic_clear_bits(jint bits);
200 
201  private:
202   friend class Method;
203   friend class Klass;
204   friend class ClassFileParser;
205   // the functions below should only be called on the _access_flags inst var directly,
206   // otherwise they are just changing a copy of the flags
207 
208   // attribute flags
209   void set_is_synthetic()              { atomic_set_bits(JVM_ACC_SYNTHETIC);               }
210 
211   // Method* flags
212   void set_monitor_matching()          { atomic_set_bits(JVM_ACC_MONITOR_MATCH);           }
213   void set_has_monitor_bytecodes()     { atomic_set_bits(JVM_ACC_HAS_MONITOR_BYTECODES);   }
214   void set_has_loops()                 { atomic_set_bits(JVM_ACC_HAS_LOOPS);               }
215   void set_loops_flag_init()           { atomic_set_bits(JVM_ACC_LOOPS_FLAG_INIT);         }
216   void set_not_c1_compilable()         { atomic_set_bits(JVM_ACC_NOT_C1_COMPILABLE);       }
217   void set_not_c2_compilable()         { atomic_set_bits(JVM_ACC_NOT_C2_COMPILABLE);       }
218   void set_not_c2_osr_compilable()     { atomic_set_bits(JVM_ACC_NOT_C2_OSR_COMPILABLE);   }
219   void set_has_linenumber_table()      { atomic_set_bits(JVM_ACC_HAS_LINE_NUMBER_TABLE);   }
220   void set_has_checked_exceptions()    { atomic_set_bits(JVM_ACC_HAS_CHECKED_EXCEPTIONS);  }
221   void set_has_jsrs()                  { atomic_set_bits(JVM_ACC_HAS_JSRS);                }
222   void set_is_old()                    { atomic_set_bits(JVM_ACC_IS_OLD);                  }
223   void set_is_obsolete()               { atomic_set_bits(JVM_ACC_IS_OBSOLETE);             }
224   void set_is_deleted()                { atomic_set_bits(JVM_ACC_IS_DELETED);              }
225   void set_is_prefixed_native()        { atomic_set_bits(JVM_ACC_IS_PREFIXED_NATIVE);      }
226 
227   void clear_not_c1_compilable()       { atomic_clear_bits(JVM_ACC_NOT_C1_COMPILABLE);       }
228   void clear_not_c2_compilable()       { atomic_clear_bits(JVM_ACC_NOT_C2_COMPILABLE);       }
229   void clear_not_c2_osr_compilable()   { atomic_clear_bits(JVM_ACC_NOT_C2_OSR_COMPILABLE);   }
230   // Klass* flags
231   void set_has_vanilla_constructor()   { atomic_set_bits(JVM_ACC_HAS_VANILLA_CONSTRUCTOR); }
232   void set_has_finalizer()             { atomic_set_bits(JVM_ACC_HAS_FINALIZER);           }
233   void set_has_final_method()          { atomic_set_bits(JVM_ACC_HAS_FINAL_METHOD);        }
234   void set_is_cloneable_fast()         { atomic_set_bits(JVM_ACC_IS_CLONEABLE_FAST);       }
235   void set_has_miranda_methods()       { atomic_set_bits(JVM_ACC_HAS_MIRANDA_METHODS);     }
236   void set_is_shared_class()           { atomic_set_bits(JVM_ACC_IS_SHARED_CLASS);         }
237   void set_is_hidden_class()           { atomic_set_bits(JVM_ACC_IS_HIDDEN_CLASS);         }
238   void set_is_value_based_class()      { atomic_set_bits(JVM_ACC_IS_VALUE_BASED_CLASS);    }
239 
240  public:
241   // field flags
242   void set_is_field_access_watched(const bool value)
243                                        {
244                                          if (value) {
245                                            atomic_set_bits(JVM_ACC_FIELD_ACCESS_WATCHED);
246                                          } else {
247                                            atomic_clear_bits(JVM_ACC_FIELD_ACCESS_WATCHED);
248                                          }
249                                        }
250   void set_is_field_modification_watched(const bool value)
251                                        {
252                                          if (value) {
253                                            atomic_set_bits(JVM_ACC_FIELD_MODIFICATION_WATCHED);
254                                          } else {
255                                            atomic_clear_bits(JVM_ACC_FIELD_MODIFICATION_WATCHED);
256                                          }
257                                        }
258 
259   void set_has_field_initialized_final_update(const bool value) {
260     if (value) {
261       atomic_set_bits(JVM_ACC_FIELD_INITIALIZED_FINAL_UPDATE);
262     } else {
263       atomic_clear_bits(JVM_ACC_FIELD_INITIALIZED_FINAL_UPDATE);
264     }
265   }
266 
267   void set_field_has_generic_signature()
268                                        {
269                                          atomic_set_bits(JVM_ACC_FIELD_HAS_GENERIC_SIGNATURE);
270                                        }
271 
272   void set_on_stack(const bool value)
273                                        {
274                                          if (value) {
275                                            atomic_set_bits(JVM_ACC_ON_STACK);
276                                          } else {
277                                            atomic_clear_bits(JVM_ACC_ON_STACK);
278                                          }
279                                        }
280   // Conversion
281   jshort as_short() const              { return (jshort)_flags; }
282   jint   as_int() const                { return _flags; }
283 
284   inline friend AccessFlags accessFlags_from(jint flags);
285 
286   // Printing/debugging
287 #if INCLUDE_JVMTI
288   void print_on(outputStream* st) const;
289 #else
290   void print_on(outputStream* st) const PRODUCT_RETURN;
291 #endif
292 };
293 
294 inline AccessFlags accessFlags_from(jint flags) {
295   AccessFlags af;
296   af._flags = flags;
297   return af;
298 }
299 
300 #endif // SHARE_UTILITIES_ACCESSFLAGS_HPP