1 /*
   2  * Copyright (c) 1997, 2013, 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_VM_UTILITIES_ACCESSFLAGS_HPP
  26 #define SHARE_VM_UTILITIES_ACCESSFLAGS_HPP
  27 
  28 #include "prims/jvm.h"
  29 #include "utilities/top.hpp"
  30 
  31 // AccessFlags is an abstraction over Java access flags.
  32 
  33 
  34 enum {
  35   // See jvm.h for shared JVM_ACC_XXX access flags
  36 
  37   // HotSpot-specific access flags
  38 
  39   // flags actually put in .class file
  40   JVM_ACC_WRITTEN_FLAGS           = 0x00007FFF,
  41 
  42   // methodOop flags
  43   JVM_ACC_MONITOR_MATCH           = 0x10000000,     // True if we know that monitorenter/monitorexit bytecodes match
  44   JVM_ACC_HAS_MONITOR_BYTECODES   = 0x20000000,     // Method contains monitorenter/monitorexit bytecodes
  45   JVM_ACC_HAS_LOOPS               = 0x40000000,     // Method has loops
  46   JVM_ACC_LOOPS_FLAG_INIT         = (int)0x80000000,// The loop flag has been initialized
  47   JVM_ACC_QUEUED                  = 0x01000000,     // Queued for compilation
  48   JVM_ACC_NOT_C2_COMPILABLE       = 0x02000000,
  49   JVM_ACC_NOT_C1_COMPILABLE       = 0x04000000,
  50   JVM_ACC_NOT_OSR_COMPILABLE      = 0x08000000,
  51   JVM_ACC_HAS_LINE_NUMBER_TABLE   = 0x00100000,
  52   JVM_ACC_HAS_CHECKED_EXCEPTIONS  = 0x00400000,
  53   JVM_ACC_HAS_JSRS                = 0x00800000,
  54   JVM_ACC_IS_OLD                  = 0x00010000,     // RedefineClasses() has replaced this method
  55   JVM_ACC_IS_OBSOLETE             = 0x00020000,     // RedefineClasses() has made method obsolete
  56   JVM_ACC_IS_PREFIXED_NATIVE      = 0x00040000,     // JVMTI has prefixed this native method
  57 
  58   JVM_MH_INVOKE_BITS           // = 0x10001100      // MethodHandle.invoke quasi-native
  59                                   = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_MONITOR_MATCH),
  60 
  61   // klassOop flags
  62   JVM_ACC_HAS_MIRANDA_METHODS     = 0x10000000,     // True if this class has miranda methods in it's vtable
  63   JVM_ACC_HAS_VANILLA_CONSTRUCTOR = 0x20000000,     // True if klass has a vanilla default constructor
  64   JVM_ACC_HAS_FINALIZER           = 0x40000000,     // True if klass has a non-empty finalize() method
  65   JVM_ACC_IS_CLONEABLE            = (int)0x80000000,// True if klass supports the Clonable interface
  66   JVM_ACC_HAS_FINAL_METHOD        = 0x01000000,     // True if klass has final method
  67 
  68   // klassOop and methodOop flags
  69   JVM_ACC_HAS_LOCAL_VARIABLE_TABLE= 0x00200000,
  70 
  71   JVM_ACC_PROMOTED_FLAGS          = 0x00200000,     // flags promoted from methods to the holding klass
  72 
  73   // field flags
  74   // Note: these flags must be defined in the low order 16 bits because
  75   // instanceKlass only stores a ushort worth of information from the
  76   // AccessFlags value.
  77   // These bits must not conflict with any other field-related access flags
  78   // (e.g., ACC_ENUM).
  79   // Note that the class-related ACC_ANNOTATION bit conflicts with these flags.
  80   JVM_ACC_FIELD_ACCESS_WATCHED       = 0x00002000,  // field access is watched by JVMTI
  81   JVM_ACC_FIELD_MODIFICATION_WATCHED = 0x00008000,  // field modification is watched by JVMTI
  82   JVM_ACC_FIELD_INTERNAL             = 0x00000400,  // internal field, same as JVM_ACC_ABSTRACT
  83 
  84   JVM_ACC_FIELD_INTERNAL_FLAGS       = JVM_ACC_FIELD_ACCESS_WATCHED |
  85                                        JVM_ACC_FIELD_MODIFICATION_WATCHED |
  86                                        JVM_ACC_FIELD_INTERNAL,
  87 
  88                                                     // flags accepted by set_field_flags()
  89   JVM_ACC_FIELD_FLAGS                = JVM_RECOGNIZED_FIELD_MODIFIERS | JVM_ACC_FIELD_INTERNAL_FLAGS
  90 
  91 };
  92 
  93 
  94 class AccessFlags VALUE_OBJ_CLASS_SPEC {
  95   friend class VMStructs;
  96  private:
  97   jint _flags;
  98 
  99  public:
 100   // Java access flags
 101   bool is_public      () const         { return (_flags & JVM_ACC_PUBLIC      ) != 0; }
 102   bool is_private     () const         { return (_flags & JVM_ACC_PRIVATE     ) != 0; }
 103   bool is_protected   () const         { return (_flags & JVM_ACC_PROTECTED   ) != 0; }
 104   bool is_static      () const         { return (_flags & JVM_ACC_STATIC      ) != 0; }
 105   bool is_final       () const         { return (_flags & JVM_ACC_FINAL       ) != 0; }
 106   bool is_synchronized() const         { return (_flags & JVM_ACC_SYNCHRONIZED) != 0; }
 107   bool is_super       () const         { return (_flags & JVM_ACC_SUPER       ) != 0; }
 108   bool is_volatile    () const         { return (_flags & JVM_ACC_VOLATILE    ) != 0; }
 109   bool is_transient   () const         { return (_flags & JVM_ACC_TRANSIENT   ) != 0; }
 110   bool is_native      () const         { return (_flags & JVM_ACC_NATIVE      ) != 0; }
 111   bool is_interface   () const         { return (_flags & JVM_ACC_INTERFACE   ) != 0; }
 112   bool is_abstract    () const         { return (_flags & JVM_ACC_ABSTRACT    ) != 0; }
 113   bool is_strict      () const         { return (_flags & JVM_ACC_STRICT      ) != 0; }
 114 
 115   // Attribute flags
 116   bool is_synthetic   () const         { return (_flags & JVM_ACC_SYNTHETIC   ) != 0; }
 117 
 118   // methodOop flags
 119   bool is_monitor_matching     () const { return (_flags & JVM_ACC_MONITOR_MATCH          ) != 0; }
 120   bool has_monitor_bytecodes   () const { return (_flags & JVM_ACC_HAS_MONITOR_BYTECODES  ) != 0; }
 121   bool has_loops               () const { return (_flags & JVM_ACC_HAS_LOOPS              ) != 0; }
 122   bool loops_flag_init         () const { return (_flags & JVM_ACC_LOOPS_FLAG_INIT        ) != 0; }
 123   bool queued_for_compilation  () const { return (_flags & JVM_ACC_QUEUED                 ) != 0; }
 124   bool is_not_c1_compilable () const    { return (_flags & JVM_ACC_NOT_C1_COMPILABLE      ) != 0; }
 125   bool is_not_c2_compilable () const    { return (_flags & JVM_ACC_NOT_C2_COMPILABLE      ) != 0; }
 126   bool is_not_osr_compilable   () const { return (_flags & JVM_ACC_NOT_OSR_COMPILABLE     ) != 0; }
 127   bool has_linenumber_table    () const { return (_flags & JVM_ACC_HAS_LINE_NUMBER_TABLE  ) != 0; }
 128   bool has_checked_exceptions  () const { return (_flags & JVM_ACC_HAS_CHECKED_EXCEPTIONS ) != 0; }
 129   bool has_jsrs                () const { return (_flags & JVM_ACC_HAS_JSRS               ) != 0; }
 130   bool is_old                  () const { return (_flags & JVM_ACC_IS_OLD                 ) != 0; }
 131   bool is_obsolete             () const { return (_flags & JVM_ACC_IS_OBSOLETE            ) != 0; }
 132   bool is_prefixed_native      () const { return (_flags & JVM_ACC_IS_PREFIXED_NATIVE     ) != 0; }
 133 
 134   // JSR 292:  A method of the form MethodHandle.invoke(A...)R method is
 135   // neither bytecoded nor a JNI native, but rather a fast call through
 136   // a lightweight method handle object.  Because it is not bytecoded,
 137   // it has the native bit set, but the monitor-match bit is also set
 138   // to distinguish it from a JNI native (which never has the match bit set).
 139   // The synthetic bit is also present, because such a method is never
 140   // explicitly defined in Java code.
 141   bool is_method_handle_invoke () const { return (_flags & JVM_MH_INVOKE_BITS) == JVM_MH_INVOKE_BITS; }
 142 
 143   // klassOop flags
 144   bool has_miranda_methods     () const { return (_flags & JVM_ACC_HAS_MIRANDA_METHODS    ) != 0; }
 145   bool has_vanilla_constructor () const { return (_flags & JVM_ACC_HAS_VANILLA_CONSTRUCTOR) != 0; }
 146   bool has_finalizer           () const { return (_flags & JVM_ACC_HAS_FINALIZER          ) != 0; }
 147   bool has_final_method        () const { return (_flags & JVM_ACC_HAS_FINAL_METHOD       ) != 0; }
 148   bool is_cloneable            () const { return (_flags & JVM_ACC_IS_CLONEABLE           ) != 0; }
 149   // klassOop and methodOop flags
 150   bool has_localvariable_table () const { return (_flags & JVM_ACC_HAS_LOCAL_VARIABLE_TABLE) != 0; }
 151   void set_has_localvariable_table()    { atomic_set_bits(JVM_ACC_HAS_LOCAL_VARIABLE_TABLE); }
 152   void clear_has_localvariable_table()  { atomic_clear_bits(JVM_ACC_HAS_LOCAL_VARIABLE_TABLE); }
 153 
 154   // field flags
 155   bool is_field_access_watched() const  { return (_flags & JVM_ACC_FIELD_ACCESS_WATCHED) != 0; }
 156   bool is_field_modification_watched() const
 157                                         { return (_flags & JVM_ACC_FIELD_MODIFICATION_WATCHED) != 0; }
 158   bool is_internal() const              { return (_flags & JVM_ACC_FIELD_INTERNAL) != 0; }
 159 
 160   // get .class file flags
 161   jint get_flags               () const { return (_flags & JVM_ACC_WRITTEN_FLAGS); }
 162 
 163   // Initialization
 164   void add_promoted_flags(jint flags)   { _flags |= (flags & JVM_ACC_PROMOTED_FLAGS); }
 165   void set_field_flags(jint flags)      {
 166     assert((flags & JVM_ACC_FIELD_FLAGS) == flags, "only recognized flags");
 167     _flags = (flags & JVM_ACC_FIELD_FLAGS);
 168   }
 169   void set_flags(jint flags)            { _flags = (flags & JVM_ACC_WRITTEN_FLAGS); }
 170 
 171   void set_queued_for_compilation()    { atomic_set_bits(JVM_ACC_QUEUED); }
 172   void clear_queued_for_compilation()  { atomic_clear_bits(JVM_ACC_QUEUED); }
 173 
 174   // Atomic update of flags
 175   void atomic_set_bits(jint bits);
 176   void atomic_clear_bits(jint bits);
 177 
 178  private:
 179   friend class methodOopDesc;
 180   friend class Klass;
 181   friend class ClassFileParser;
 182   // the functions below should only be called on the _access_flags inst var directly,
 183   // otherwise they are just changing a copy of the flags
 184 
 185   // attribute flags
 186   void set_is_synthetic()              { atomic_set_bits(JVM_ACC_SYNTHETIC);               }
 187 
 188   // methodOop flags
 189   void set_monitor_matching()          { atomic_set_bits(JVM_ACC_MONITOR_MATCH);           }
 190   void set_has_monitor_bytecodes()     { atomic_set_bits(JVM_ACC_HAS_MONITOR_BYTECODES);   }
 191   void set_has_loops()                 { atomic_set_bits(JVM_ACC_HAS_LOOPS);               }
 192   void set_loops_flag_init()           { atomic_set_bits(JVM_ACC_LOOPS_FLAG_INIT);         }
 193   void set_not_c1_compilable()         { atomic_set_bits(JVM_ACC_NOT_C1_COMPILABLE);       }
 194   void set_not_c2_compilable()         { atomic_set_bits(JVM_ACC_NOT_C2_COMPILABLE);       }
 195   void set_not_osr_compilable()        { atomic_set_bits(JVM_ACC_NOT_OSR_COMPILABLE);      }
 196   void set_has_linenumber_table()      { atomic_set_bits(JVM_ACC_HAS_LINE_NUMBER_TABLE);   }
 197   void set_has_checked_exceptions()    { atomic_set_bits(JVM_ACC_HAS_CHECKED_EXCEPTIONS);  }
 198   void set_has_jsrs()                  { atomic_set_bits(JVM_ACC_HAS_JSRS);                }
 199   void set_is_old()                    { atomic_set_bits(JVM_ACC_IS_OLD);                  }
 200   void set_is_obsolete()               { atomic_set_bits(JVM_ACC_IS_OBSOLETE);             }
 201   void set_is_prefixed_native()        { atomic_set_bits(JVM_ACC_IS_PREFIXED_NATIVE);      }
 202 
 203   // klassOop flags
 204   void set_has_vanilla_constructor()   { atomic_set_bits(JVM_ACC_HAS_VANILLA_CONSTRUCTOR); }
 205   void set_has_finalizer()             { atomic_set_bits(JVM_ACC_HAS_FINALIZER);           }
 206   void set_has_final_method()          { atomic_set_bits(JVM_ACC_HAS_FINAL_METHOD);        }
 207   void set_is_cloneable()              { atomic_set_bits(JVM_ACC_IS_CLONEABLE);            }
 208   void set_has_miranda_methods()       { atomic_set_bits(JVM_ACC_HAS_MIRANDA_METHODS);     }
 209 
 210  public:
 211   // field flags
 212   void set_is_field_access_watched(const bool value)
 213                                        {
 214                                          if (value) {
 215                                            atomic_set_bits(JVM_ACC_FIELD_ACCESS_WATCHED);
 216                                          } else {
 217                                            atomic_clear_bits(JVM_ACC_FIELD_ACCESS_WATCHED);
 218                                          }
 219                                        }
 220   void set_is_field_modification_watched(const bool value)
 221                                        {
 222                                          if (value) {
 223                                            atomic_set_bits(JVM_ACC_FIELD_MODIFICATION_WATCHED);
 224                                          } else {
 225                                            atomic_clear_bits(JVM_ACC_FIELD_MODIFICATION_WATCHED);
 226                                          }
 227                                        }
 228 
 229   // Conversion
 230   jshort as_short() const              { return (jshort)_flags; }
 231   jint   as_int() const                { return _flags; }
 232 
 233   inline friend AccessFlags accessFlags_from(jint flags);
 234 
 235   // Printing/debugging
 236   void print_on(outputStream* st) const;
 237 };
 238 
 239 inline AccessFlags accessFlags_from(jint flags) {
 240   AccessFlags af;
 241   af._flags = flags;
 242   return af;
 243 }
 244 
 245 #endif // SHARE_VM_UTILITIES_ACCESSFLAGS_HPP