1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
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  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  *
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 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_OOPS_INSTANCEKLASSFLAGS_HPP
 26 #define SHARE_OOPS_INSTANCEKLASSFLAGS_HPP
 27 
 28 class ClassLoaderData;
 29 
 30 // The InstanceKlassFlags class contains the parse-time and writeable flags associated with
 31 // an InstanceKlass, and their associated accessors.
 32 // _flags are parse-time and constant in the InstanceKlass after that.  _status are set at runtime and
 33 // require atomic access.
 34 // These flags are JVM internal and not part of the AccessFlags classfile specification.
 35 
 36 class InstanceKlassFlags {
 37   friend class VMStructs;
 38   friend class JVMCIVMStructs;
 39 
 40 #define IK_FLAGS_DO(flag)  \
 41     flag(rewritten                          , 1 << 0) /* methods rewritten. */ \
 42     flag(has_nonstatic_fields               , 1 << 1) /* for sizing with UseCompressedOops */ \
 43     flag(should_verify_class                , 1 << 2) /* allow caching of preverification */ \
 44     flag(is_contended                       , 1 << 3) /* marked with contended annotation */ \
 45     flag(has_nonstatic_concrete_methods     , 1 << 4) /* class/superclass/implemented interfaces has non-static, concrete methods */ \
 46     flag(declares_nonstatic_concrete_methods, 1 << 5) /* directly declares non-static, concrete methods */ \
 47     flag(shared_loading_failed              , 1 << 6) /* class has been loaded from shared archive */ \
 48     flag(is_shared_boot_class               , 1 << 7) /* defining class loader is boot class loader */ \
 49     flag(is_shared_platform_class           , 1 << 8) /* defining class loader is platform class loader */ \
 50     flag(is_shared_app_class                , 1 << 9) /* defining class loader is app class loader */ \
 51     flag(has_contended_annotations          , 1 << 10) /* has @Contended annotation */ \
 52     flag(has_localvariable_table            , 1 << 11) /* has localvariable information */ \
 53     flag(has_miranda_methods                , 1 << 12) /* True if this class has miranda methods in it's vtable */ \
 54     flag(has_vanilla_constructor            , 1 << 13) /* True if klass has a vanilla default constructor */ \
 55     flag(has_final_method                   , 1 << 14) /* True if klass has final method */ \
 56     /* end of list */
 57 
 58 #define IK_FLAGS_ENUM_NAME(name, value)    _misc_##name = value,
 59   enum {
 60     IK_FLAGS_DO(IK_FLAGS_ENUM_NAME)
 61   };
 62 #undef IK_FLAGS_ENUM_NAME
 63 
 64 #define IK_STATUS_DO(status)  \
 65     status(is_being_redefined                , 1 << 0) /* True if the klass is being redefined */ \
 66     status(has_resolved_methods              , 1 << 1) /* True if the klass has resolved MethodHandle methods */ \
 67     status(has_been_redefined                , 1 << 2) /* class has been redefined */ \
 68     status(is_scratch_class                  , 1 << 3) /* class is the redefined scratch class */ \
 69     status(is_marked_dependent               , 1 << 4) /* class is the redefined scratch class */
 70 
 71 #define IK_STATUS_ENUM_NAME(name, value)    _misc_##name = value,
 72   enum {
 73     IK_STATUS_DO(IK_STATUS_ENUM_NAME)
 74   };
 75 #undef IK_STATUS_ENUM_NAME
 76 
 77   u2 shared_loader_type_bits() const {
 78     return _misc_is_shared_boot_class|_misc_is_shared_platform_class|_misc_is_shared_app_class;
 79   }
 80 
 81   // These flags are write-once before the class is published and then read-only so don't require atomic updates.
 82   u2 _flags;
 83 
 84   // These flags are written during execution so require atomic stores
 85   u1 _status;
 86 
 87  public:
 88 
 89   InstanceKlassFlags() : _flags(0), _status(0) {}
 90 
 91   // Create getters and setters for the flag values.
 92 #define IK_FLAGS_GET(name, ignore)          \
 93   bool name() const { return (_flags & _misc_##name) != 0; }
 94   IK_FLAGS_DO(IK_FLAGS_GET)
 95 #undef IK_FLAGS_GET
 96 
 97 #define IK_FLAGS_SET(name, ignore)   \
 98   void set_##name(bool b) {         \
 99     assert_is_safe(name());         \
100     if (b) _flags |= _misc_##name; \
101   }
102   IK_FLAGS_DO(IK_FLAGS_SET)
103 #undef IK_FLAGS_SET
104 
105   bool is_shared_unregistered_class() const {
106     return (_flags & shared_loader_type_bits()) == 0;
107   }
108 
109   void set_shared_class_loader_type(s2 loader_type);
110 
111   void assign_class_loader_type(const ClassLoaderData* cld);
112   void assert_is_safe(bool set) NOT_DEBUG_RETURN;
113 
114   // Create getters and setters for the status values.
115 #define IK_STATUS_GET(name, ignore)          \
116   bool name() const { return (_status & _misc_##name) != 0; }
117   IK_STATUS_DO(IK_STATUS_GET)
118 #undef IK_STATUS_GET
119 
120 #define IK_STATUS_SET(name, ignore)   \
121   void set_##name(bool b) {         \
122     if (b) { \
123       atomic_set_bits(_misc_##name); \
124     } else { \
125       atomic_clear_bits(_misc_##name); \
126     } \
127   }
128   IK_STATUS_DO(IK_STATUS_SET)
129 #undef IK_STATUS_SET
130 
131   void atomic_set_bits(u1 bits);
132   void atomic_clear_bits(u1 bits);
133 };
134 
135 #endif // SHARE_OOPS_INSTANCEKLASSFLAGS_HPP