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24 
25 #ifndef SHARE_VM_UTILITIES_ACCESSFLAGS_HPP
26 #define SHARE_VM_UTILITIES_ACCESSFLAGS_HPP
27 
28 #include "jvm.h"
29 #include "utilities/debug.hpp"
30 #include "utilities/macros.hpp"
31 
32 // AccessFlags is an abstraction over Java access flags.
33 
34 class outputStream;
35 
36 enum {
37   // See jvm.h for shared JVM_ACC_XXX access flags
38 
39   // HotSpot-specific access flags
40 
41   // flags actually put in .class file
42   JVM_ACC_WRITTEN_FLAGS           = 0x00007FFF,
43 
44   // Method* flags
45   JVM_ACC_MONITOR_MATCH           = 0x10000000,     // True if we know that monitorenter/monitorexit bytecodes match
46   JVM_ACC_HAS_MONITOR_BYTECODES   = 0x20000000,     // Method contains monitorenter/monitorexit bytecodes
47   JVM_ACC_HAS_LOOPS               = 0x40000000,     // Method has loops
48   JVM_ACC_LOOPS_FLAG_INIT         = (int)0x80000000,// The loop flag has been initialized
49   JVM_ACC_QUEUED                  = 0x01000000,     // Queued for compilation
50   JVM_ACC_NOT_C2_COMPILABLE       = 0x02000000,
51   JVM_ACC_NOT_C1_COMPILABLE       = 0x04000000,
52   JVM_ACC_NOT_C2_OSR_COMPILABLE   = 0x08000000,
53   JVM_ACC_HAS_LINE_NUMBER_TABLE   = 0x00100000,
54   JVM_ACC_HAS_CHECKED_EXCEPTIONS  = 0x00400000,
55   JVM_ACC_HAS_JSRS                = 0x00800000,
56   JVM_ACC_IS_OLD                  = 0x00010000,     // RedefineClasses() has replaced this method
57   JVM_ACC_IS_OBSOLETE             = 0x00020000,     // RedefineClasses() has made method obsolete
58   JVM_ACC_IS_PREFIXED_NATIVE      = 0x00040000,     // JVMTI has prefixed this native method
59   JVM_ACC_ON_STACK                = 0x00080000,     // RedefineClasses() was used on the stack
60   JVM_ACC_IS_DELETED              = 0x00008000,     // RedefineClasses() has deleted this method
61 
62   // Klass* flags
63   JVM_ACC_HAS_MIRANDA_METHODS     = 0x10000000,     // True if this class has miranda methods in it's vtable
64   JVM_ACC_HAS_VANILLA_CONSTRUCTOR = 0x20000000,     // True if klass has a vanilla default constructor
65   JVM_ACC_HAS_FINALIZER           = 0x40000000,     // True if klass has a non-empty finalize() method
66   JVM_ACC_IS_CLONEABLE_FAST       = (int)0x80000000,// True if klass implements the Cloneable interface and can be optimized in generated code
67   JVM_ACC_HAS_FINAL_METHOD        = 0x01000000,     // True if klass has final method
68   JVM_ACC_IS_SHARED_CLASS         = 0x02000000,     // True if klass is shared
69 
70   // Klass* and Method* flags
71   JVM_ACC_HAS_LOCAL_VARIABLE_TABLE= 0x00200000,
72 
73   JVM_ACC_PROMOTED_FLAGS          = 0x00200000,     // flags promoted from methods to the holding klass
74 
75   // field flags
76   // Note: these flags must be defined in the low order 16 bits because
77   // InstanceKlass only stores a ushort worth of information from the
78   // AccessFlags value.
79   // These bits must not conflict with any other field-related access flags
80   // (e.g., ACC_ENUM).
81   // Note that the class-related ACC_ANNOTATION bit conflicts with these flags.
82   JVM_ACC_FIELD_ACCESS_WATCHED            = 0x00002000, // field access is watched by JVMTI
83   JVM_ACC_FIELD_MODIFICATION_WATCHED      = 0x00008000, // field modification is watched by JVMTI
84   JVM_ACC_FIELD_INTERNAL                  = 0x00000400, // internal field, same as JVM_ACC_ABSTRACT
85   JVM_ACC_FIELD_STABLE                    = 0x00000020, // @Stable field, same as JVM_ACC_SYNCHRONIZED and JVM_ACC_SUPER
86   JVM_ACC_FIELD_INITIALIZED_FINAL_UPDATE  = 0x00000100, // (static) final field updated outside (class) initializer, same as JVM_ACC_NATIVE
87   JVM_ACC_FIELD_HAS_GENERIC_SIGNATURE     = 0x00000800, // field has generic signature
88 
89   JVM_ACC_FIELD_INTERNAL_FLAGS       = JVM_ACC_FIELD_ACCESS_WATCHED |
90                                        JVM_ACC_FIELD_MODIFICATION_WATCHED |
91                                        JVM_ACC_FIELD_INTERNAL |
92                                        JVM_ACC_FIELD_STABLE |
93                                        JVM_ACC_FIELD_HAS_GENERIC_SIGNATURE,
94 
95                                                     // flags accepted by set_field_flags()
96   JVM_ACC_FIELD_FLAGS                = JVM_RECOGNIZED_FIELD_MODIFIERS | JVM_ACC_FIELD_INTERNAL_FLAGS
97 
98 };
99 
100 
101 class AccessFlags {
102   friend class VMStructs;
103  private:
104   jint _flags;
105 
106  public:
AccessFlags()107   AccessFlags() : _flags(0) {}
AccessFlags(jint flags)108   explicit AccessFlags(jint flags) : _flags(flags) {}
109 
110   // Java access flags
is_public() const111   bool is_public      () const         { return (_flags & JVM_ACC_PUBLIC      ) != 0; }
is_private() const112   bool is_private     () const         { return (_flags & JVM_ACC_PRIVATE     ) != 0; }
is_protected() const113   bool is_protected   () const         { return (_flags & JVM_ACC_PROTECTED   ) != 0; }
is_static() const114   bool is_static      () const         { return (_flags & JVM_ACC_STATIC      ) != 0; }
is_final() const115   bool is_final       () const         { return (_flags & JVM_ACC_FINAL       ) != 0; }
is_synchronized() const116   bool is_synchronized() const         { return (_flags & JVM_ACC_SYNCHRONIZED) != 0; }
is_super() const117   bool is_super       () const         { return (_flags & JVM_ACC_SUPER       ) != 0; }
is_volatile() const118   bool is_volatile    () const         { return (_flags & JVM_ACC_VOLATILE    ) != 0; }
is_transient() const119   bool is_transient   () const         { return (_flags & JVM_ACC_TRANSIENT   ) != 0; }
is_native() const120   bool is_native      () const         { return (_flags & JVM_ACC_NATIVE      ) != 0; }
is_interface() const121   bool is_interface   () const         { return (_flags & JVM_ACC_INTERFACE   ) != 0; }
is_abstract() const122   bool is_abstract    () const         { return (_flags & JVM_ACC_ABSTRACT    ) != 0; }
is_strict() const123   bool is_strict      () const         { return (_flags & JVM_ACC_STRICT      ) != 0; }
124 
125   // Attribute flags
is_synthetic() const126   bool is_synthetic   () const         { return (_flags & JVM_ACC_SYNTHETIC   ) != 0; }
127 
128   // Method* flags
is_monitor_matching() const129   bool is_monitor_matching     () const { return (_flags & JVM_ACC_MONITOR_MATCH          ) != 0; }
has_monitor_bytecodes() const130   bool has_monitor_bytecodes   () const { return (_flags & JVM_ACC_HAS_MONITOR_BYTECODES  ) != 0; }
has_loops() const131   bool has_loops               () const { return (_flags & JVM_ACC_HAS_LOOPS              ) != 0; }
loops_flag_init() const132   bool loops_flag_init         () const { return (_flags & JVM_ACC_LOOPS_FLAG_INIT        ) != 0; }
queued_for_compilation() const133   bool queued_for_compilation  () const { return (_flags & JVM_ACC_QUEUED                 ) != 0; }
is_not_c1_compilable() const134   bool is_not_c1_compilable    () const { return (_flags & JVM_ACC_NOT_C1_COMPILABLE      ) != 0; }
is_not_c2_compilable() const135   bool is_not_c2_compilable    () const { return (_flags & JVM_ACC_NOT_C2_COMPILABLE      ) != 0; }
is_not_c2_osr_compilable() const136   bool is_not_c2_osr_compilable() const { return (_flags & JVM_ACC_NOT_C2_OSR_COMPILABLE  ) != 0; }
has_linenumber_table() const137   bool has_linenumber_table    () const { return (_flags & JVM_ACC_HAS_LINE_NUMBER_TABLE  ) != 0; }
has_checked_exceptions() const138   bool has_checked_exceptions  () const { return (_flags & JVM_ACC_HAS_CHECKED_EXCEPTIONS ) != 0; }
has_jsrs() const139   bool has_jsrs                () const { return (_flags & JVM_ACC_HAS_JSRS               ) != 0; }
is_old() const140   bool is_old                  () const { return (_flags & JVM_ACC_IS_OLD                 ) != 0; }
is_obsolete() const141   bool is_obsolete             () const { return (_flags & JVM_ACC_IS_OBSOLETE            ) != 0; }
is_deleted() const142   bool is_deleted              () const { return (_flags & JVM_ACC_IS_DELETED             ) != 0; }
is_prefixed_native() const143   bool is_prefixed_native      () const { return (_flags & JVM_ACC_IS_PREFIXED_NATIVE     ) != 0; }
144 
145   // Klass* flags
has_miranda_methods() const146   bool has_miranda_methods     () const { return (_flags & JVM_ACC_HAS_MIRANDA_METHODS    ) != 0; }
has_vanilla_constructor() const147   bool has_vanilla_constructor () const { return (_flags & JVM_ACC_HAS_VANILLA_CONSTRUCTOR) != 0; }
has_finalizer() const148   bool has_finalizer           () const { return (_flags & JVM_ACC_HAS_FINALIZER          ) != 0; }
has_final_method() const149   bool has_final_method        () const { return (_flags & JVM_ACC_HAS_FINAL_METHOD       ) != 0; }
is_cloneable_fast() const150   bool is_cloneable_fast       () const { return (_flags & JVM_ACC_IS_CLONEABLE_FAST      ) != 0; }
is_shared_class() const151   bool is_shared_class         () const { return (_flags & JVM_ACC_IS_SHARED_CLASS        ) != 0; }
152 
153   // Klass* and Method* flags
has_localvariable_table() const154   bool has_localvariable_table () const { return (_flags & JVM_ACC_HAS_LOCAL_VARIABLE_TABLE) != 0; }
set_has_localvariable_table()155   void set_has_localvariable_table()    { atomic_set_bits(JVM_ACC_HAS_LOCAL_VARIABLE_TABLE); }
clear_has_localvariable_table()156   void clear_has_localvariable_table()  { atomic_clear_bits(JVM_ACC_HAS_LOCAL_VARIABLE_TABLE); }
157 
158   // field flags
is_field_access_watched() const159   bool is_field_access_watched() const  { return (_flags & JVM_ACC_FIELD_ACCESS_WATCHED) != 0; }
is_field_modification_watched() const160   bool is_field_modification_watched() const
161                                         { return (_flags & JVM_ACC_FIELD_MODIFICATION_WATCHED) != 0; }
has_field_initialized_final_update() const162   bool has_field_initialized_final_update() const
163                                         { return (_flags & JVM_ACC_FIELD_INITIALIZED_FINAL_UPDATE) != 0; }
on_stack() const164   bool on_stack() const                 { return (_flags & JVM_ACC_ON_STACK) != 0; }
is_internal() const165   bool is_internal() const              { return (_flags & JVM_ACC_FIELD_INTERNAL) != 0; }
is_stable() const166   bool is_stable() const                { return (_flags & JVM_ACC_FIELD_STABLE) != 0; }
field_has_generic_signature() const167   bool field_has_generic_signature() const
168                                         { return (_flags & JVM_ACC_FIELD_HAS_GENERIC_SIGNATURE) != 0; }
169 
170   // get .class file flags
get_flags() const171   jint get_flags               () const { return (_flags & JVM_ACC_WRITTEN_FLAGS); }
172 
173   // Initialization
add_promoted_flags(jint flags)174   void add_promoted_flags(jint flags)   { _flags |= (flags & JVM_ACC_PROMOTED_FLAGS); }
set_field_flags(jint flags)175   void set_field_flags(jint flags)      {
176     assert((flags & JVM_ACC_FIELD_FLAGS) == flags, "only recognized flags");
177     _flags = (flags & JVM_ACC_FIELD_FLAGS);
178   }
set_flags(jint flags)179   void set_flags(jint flags)            { _flags = (flags & JVM_ACC_WRITTEN_FLAGS); }
180 
set_queued_for_compilation()181   void set_queued_for_compilation()    { atomic_set_bits(JVM_ACC_QUEUED); }
clear_queued_for_compilation()182   void clear_queued_for_compilation()  { atomic_clear_bits(JVM_ACC_QUEUED); }
183 
184   // Atomic update of flags
185   void atomic_set_bits(jint bits);
186   void atomic_clear_bits(jint bits);
187 
188  private:
189   friend class Method;
190   friend class Klass;
191   friend class ClassFileParser;
192   // the functions below should only be called on the _access_flags inst var directly,
193   // otherwise they are just changing a copy of the flags
194 
195   // attribute flags
set_is_synthetic()196   void set_is_synthetic()              { atomic_set_bits(JVM_ACC_SYNTHETIC);               }
197 
198   // Method* flags
set_monitor_matching()199   void set_monitor_matching()          { atomic_set_bits(JVM_ACC_MONITOR_MATCH);           }
set_has_monitor_bytecodes()200   void set_has_monitor_bytecodes()     { atomic_set_bits(JVM_ACC_HAS_MONITOR_BYTECODES);   }
set_has_loops()201   void set_has_loops()                 { atomic_set_bits(JVM_ACC_HAS_LOOPS);               }
set_loops_flag_init()202   void set_loops_flag_init()           { atomic_set_bits(JVM_ACC_LOOPS_FLAG_INIT);         }
set_not_c1_compilable()203   void set_not_c1_compilable()         { atomic_set_bits(JVM_ACC_NOT_C1_COMPILABLE);       }
set_not_c2_compilable()204   void set_not_c2_compilable()         { atomic_set_bits(JVM_ACC_NOT_C2_COMPILABLE);       }
set_not_c2_osr_compilable()205   void set_not_c2_osr_compilable()     { atomic_set_bits(JVM_ACC_NOT_C2_OSR_COMPILABLE);   }
set_has_linenumber_table()206   void set_has_linenumber_table()      { atomic_set_bits(JVM_ACC_HAS_LINE_NUMBER_TABLE);   }
set_has_checked_exceptions()207   void set_has_checked_exceptions()    { atomic_set_bits(JVM_ACC_HAS_CHECKED_EXCEPTIONS);  }
set_has_jsrs()208   void set_has_jsrs()                  { atomic_set_bits(JVM_ACC_HAS_JSRS);                }
set_is_old()209   void set_is_old()                    { atomic_set_bits(JVM_ACC_IS_OLD);                  }
set_is_obsolete()210   void set_is_obsolete()               { atomic_set_bits(JVM_ACC_IS_OBSOLETE);             }
set_is_deleted()211   void set_is_deleted()                { atomic_set_bits(JVM_ACC_IS_DELETED);              }
set_is_prefixed_native()212   void set_is_prefixed_native()        { atomic_set_bits(JVM_ACC_IS_PREFIXED_NATIVE);      }
213 
clear_not_c1_compilable()214   void clear_not_c1_compilable()       { atomic_clear_bits(JVM_ACC_NOT_C1_COMPILABLE);       }
clear_not_c2_compilable()215   void clear_not_c2_compilable()       { atomic_clear_bits(JVM_ACC_NOT_C2_COMPILABLE);       }
clear_not_c2_osr_compilable()216   void clear_not_c2_osr_compilable()   { atomic_clear_bits(JVM_ACC_NOT_C2_OSR_COMPILABLE);   }
217   // Klass* flags
set_has_vanilla_constructor()218   void set_has_vanilla_constructor()   { atomic_set_bits(JVM_ACC_HAS_VANILLA_CONSTRUCTOR); }
set_has_finalizer()219   void set_has_finalizer()             { atomic_set_bits(JVM_ACC_HAS_FINALIZER);           }
set_has_final_method()220   void set_has_final_method()          { atomic_set_bits(JVM_ACC_HAS_FINAL_METHOD);        }
set_is_cloneable_fast()221   void set_is_cloneable_fast()         { atomic_set_bits(JVM_ACC_IS_CLONEABLE_FAST);       }
set_has_miranda_methods()222   void set_has_miranda_methods()       { atomic_set_bits(JVM_ACC_HAS_MIRANDA_METHODS);     }
set_is_shared_class()223   void set_is_shared_class()           { atomic_set_bits(JVM_ACC_IS_SHARED_CLASS);         }
224 
225  public:
226   // field flags
set_is_field_access_watched(const bool value)227   void set_is_field_access_watched(const bool value)
228                                        {
229                                          if (value) {
230                                            atomic_set_bits(JVM_ACC_FIELD_ACCESS_WATCHED);
231                                          } else {
232                                            atomic_clear_bits(JVM_ACC_FIELD_ACCESS_WATCHED);
233                                          }
234                                        }
set_is_field_modification_watched(const bool value)235   void set_is_field_modification_watched(const bool value)
236                                        {
237                                          if (value) {
238                                            atomic_set_bits(JVM_ACC_FIELD_MODIFICATION_WATCHED);
239                                          } else {
240                                            atomic_clear_bits(JVM_ACC_FIELD_MODIFICATION_WATCHED);
241                                          }
242                                        }
243 
set_has_field_initialized_final_update(const bool value)244   void set_has_field_initialized_final_update(const bool value) {
245     if (value) {
246       atomic_set_bits(JVM_ACC_FIELD_INITIALIZED_FINAL_UPDATE);
247     } else {
248       atomic_clear_bits(JVM_ACC_FIELD_INITIALIZED_FINAL_UPDATE);
249     }
250   }
251 
set_field_has_generic_signature()252   void set_field_has_generic_signature()
253                                        {
254                                          atomic_set_bits(JVM_ACC_FIELD_HAS_GENERIC_SIGNATURE);
255                                        }
256 
set_on_stack(const bool value)257   void set_on_stack(const bool value)
258                                        {
259                                          if (value) {
260                                            atomic_set_bits(JVM_ACC_ON_STACK);
261                                          } else {
262                                            atomic_clear_bits(JVM_ACC_ON_STACK);
263                                          }
264                                        }
265   // Conversion
as_short() const266   jshort as_short() const              { return (jshort)_flags; }
as_int() const267   jint   as_int() const                { return _flags; }
268 
269   inline friend AccessFlags accessFlags_from(jint flags);
270 
271   // Printing/debugging
272 #if INCLUDE_JVMTI
273   void print_on(outputStream* st) const;
274 #else
275   void print_on(outputStream* st) const PRODUCT_RETURN;
276 #endif
277 };
278 
accessFlags_from(jint flags)279 inline AccessFlags accessFlags_from(jint flags) {
280   AccessFlags af;
281   af._flags = flags;
282   return af;
283 }
284 
285 #endif // SHARE_VM_UTILITIES_ACCESSFLAGS_HPP
286