1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  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.
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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  *
 15  * You should have received a copy of the GNU General Public License version
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 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
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 24 
 25 #ifndef SHARE_OOPS_INSTANCEKLASSFLAGS_HPP
 26 #define SHARE_OOPS_INSTANCEKLASSFLAGS_HPP
 27 
 28 #include "runtime/atomic.hpp"
 29 
 30 class ClassLoaderData;
 31 
 32 // The InstanceKlassFlags class contains the parse-time and writeable flags associated with
 33 // an InstanceKlass, and their associated accessors.
 34 // _flags are parse-time and constant in the InstanceKlass after that.  _status are set at runtime and
 35 // require atomic access.
 36 // These flags are JVM internal and not part of the AccessFlags classfile specification.
 37 
 38 class InstanceKlassFlags {
 39   friend class VMStructs;
 40   friend class JVMCIVMStructs;
 41 
 42 #define IK_FLAGS_DO(flag)  \
 43     flag(rewritten                          , 1 << 0) /* methods rewritten. */ \
 44     flag(has_nonstatic_fields               , 1 << 1) /* for sizing with UseCompressedOops */ \
 45     flag(should_verify_class                , 1 << 2) /* allow caching of preverification */ \
 46     flag(is_contended                       , 1 << 3) /* marked with contended annotation */ \
 47     flag(has_nonstatic_concrete_methods     , 1 << 4) /* class/superclass/implemented interfaces has non-static, concrete methods */ \
 48     flag(declares_nonstatic_concrete_methods, 1 << 5) /* directly declares non-static, concrete methods */ \
 49     flag(shared_loading_failed              , 1 << 6) /* class has been loaded from shared archive */ \
 50     flag(defined_by_boot_loader             , 1 << 7) /* defining class loader is boot class loader */ \
 51     flag(defined_by_platform_loader         , 1 << 8) /* defining class loader is platform class loader */ \
 52     flag(defined_by_app_loader              , 1 << 9) /* defining class loader is app class loader */ \
 53     flag(has_contended_annotations          , 1 << 10) /* has @Contended annotation */ \
 54     flag(has_localvariable_table            , 1 << 11) /* has localvariable information */ \
 55     flag(has_miranda_methods                , 1 << 12) /* True if this class has miranda methods in it's vtable */ \
 56     flag(has_final_method                   , 1 << 13) /* True if klass has final method */ \
 57     flag(has_aot_safe_initializer           , 1 << 14) /* has @AOTSafeClassInitializer annotation */ \
 58     flag(is_runtime_setup_required          , 1 << 15) /* has a runtimeSetup method to be called */ \
 59     flag(has_inline_type_fields             , 1 << 16) /* has inline fields and related embedded section is not empty */ \
 60     flag(is_empty_inline_type               , 1 << 17) /* empty inline type (*) */ \
 61     flag(is_naturally_atomic                , 1 << 18) /* loaded/stored in one instruction*/ \
 62     flag(must_be_atomic                     , 1 << 19) /* doesn't allow tearing */ \
 63     flag(has_loosely_consistent_annotation  , 1 << 20) /* the class has the LooselyConsistentValue annotation WARNING: it doesn't automatically mean that the class allows tearing */ \
 64     flag(has_strict_static_fields           , 1 << 21) /* True if strict static fields declared */ \
 65     /* end of list */
 66 
 67   /* (*) An inline type is considered empty if it contains no non-static fields or
 68      if it contains only empty inline fields. Note that JITs have a slightly different
 69      definition: empty inline fields must be flat otherwise the container won't
 70      be considered empty */
 71 
 72 #define IK_FLAGS_ENUM_NAME(name, value)    _misc_##name = value,
 73   enum {
 74     IK_FLAGS_DO(IK_FLAGS_ENUM_NAME)
 75   };
 76 #undef IK_FLAGS_ENUM_NAME
 77 
 78 #define IK_STATUS_DO(status)  \
 79     status(is_being_redefined                , 1 << 0) /* True if the klass is being redefined */ \
 80     status(has_resolved_methods              , 1 << 1) /* True if the klass has resolved MethodHandle methods */ \
 81     status(has_been_redefined                , 1 << 2) /* class has been redefined */ \
 82     status(is_scratch_class                  , 1 << 3) /* class is the redefined scratch class */ \
 83     status(is_marked_dependent               , 1 << 4) /* class is the redefined scratch class */ \
 84     status(has_init_deps_processed           , 1 << 5) /* all init dependencies are processed */ \
 85     /* end of list */
 86 
 87 #define IK_STATUS_ENUM_NAME(name, value)    _misc_##name = value,
 88   enum {
 89     IK_STATUS_DO(IK_STATUS_ENUM_NAME)
 90   };
 91 #undef IK_STATUS_ENUM_NAME
 92 
 93   u2 builtin_loader_type_bits() const {
 94     return _misc_defined_by_boot_loader|_misc_defined_by_platform_loader|_misc_defined_by_app_loader;
 95   }
 96 
 97   // These flags are write-once before the class is published and then read-only so don't require atomic updates.
 98   u4 _flags;
 99 
100   // These flags are written during execution so require atomic stores
101   u1 _status;
102 
103  public:
104 
105   InstanceKlassFlags() : _flags(0), _status(0) {}
106 
107   // Create getters and setters for the flag values.
108 #define IK_FLAGS_GET_SET(name, ignore)          \
109   bool name() const { return (_flags & _misc_##name) != 0; } \
110   void set_##name(bool b) {         \
111     assert_is_safe(name());         \
112     if (b) _flags |= _misc_##name; \
113   }
114   IK_FLAGS_DO(IK_FLAGS_GET_SET)
115 #undef IK_FLAGS_GET_SET
116 
117   bool defined_by_other_loaders() const {
118     return (_flags & builtin_loader_type_bits()) == 0;
119   }
120 
121   void set_class_loader_type(const ClassLoaderData* cld);
122 
123 
124   u4 flags() const { return _flags; }
125 
126   static u4 is_empty_inline_type_value() {
127     return _misc_is_empty_inline_type;
128   }
129 
130   void assert_is_safe(bool set) NOT_DEBUG_RETURN;
131 
132   // Create getters and setters for the status values.
133 #define IK_STATUS_GET_SET(name, ignore)          \
134   bool name() const { return (_status & _misc_##name) != 0; } \
135   void set_##name(bool b) {         \
136     if (b) { \
137       atomic_set_bits(_misc_##name); \
138     } else { \
139       atomic_clear_bits(_misc_##name); \
140     } \
141   }
142   IK_STATUS_DO(IK_STATUS_GET_SET)
143 #undef IK_STATUS_GET_SET
144 
145   void atomic_set_bits(u1 bits)   { Atomic::fetch_then_or(&_status, bits); }
146   void atomic_clear_bits(u1 bits) { Atomic::fetch_then_and(&_status, (u1)(~bits)); }
147   void print_on(outputStream* st) const;
148 };
149 
150 #endif // SHARE_OOPS_INSTANCEKLASSFLAGS_HPP