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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  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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  24 
  25 #ifndef SHARE_OOPS_INSTANCEMIRRORKLASS_INLINE_HPP
  26 #define SHARE_OOPS_INSTANCEMIRRORKLASS_INLINE_HPP
  27 
  28 #include "classfile/javaClasses.hpp"
  29 #include "oops/instanceKlass.inline.hpp"
  30 #include "oops/instanceMirrorKlass.hpp"
  31 #include "oops/klass.hpp"
  32 #include "oops/oop.inline.hpp"
  33 #include "utilities/debug.hpp"
  34 #include "utilities/globalDefinitions.hpp"
  35 #include "utilities/macros.hpp"
  36 
  37 template <typename T, class OopClosureType>
  38 void InstanceMirrorKlass::oop_oop_iterate_statics(oop obj, OopClosureType* closure) {
  39   T* p         = (T*)start_of_static_fields(obj);
  40   T* const end = p + java_lang_Class::static_oop_field_count_raw(obj);
  41 
  42   for (; p < end; ++p) {
  43     Devirtualizer::do_oop(closure, p);
  44   }
  45 }
  46 
  47 template <typename T, class OopClosureType>
  48 void InstanceMirrorKlass::oop_oop_iterate(oop obj, OopClosureType* closure) {
  49   InstanceKlass::oop_oop_iterate<T>(obj, closure);
  50 
  51   if (Devirtualizer::do_metadata(closure)) {
  52     Klass* klass = java_lang_Class::as_Klass_raw(obj);
  53     // We'll get NULL for primitive mirrors.
  54     if (klass != NULL) {
  55       if (klass->is_instance_klass() && klass->class_loader_data()->has_class_mirror_holder()) {
  56         // A weak hidden or an unsafe anonymous class doesn't have its own class loader,
  57         // so when handling the java mirror for the class we need to make sure its class
  58         // loader data is claimed, this is done by calling do_cld explicitly.
  59         // For non-anonymous classes the call to do_cld is made when the class
  60         // loader itself is handled.
  61         Devirtualizer::do_cld(closure, klass->class_loader_data());
  62       } else {
  63         Devirtualizer::do_klass(closure, klass);
  64       }
  65     } else {
  66       // We would like to assert here (as below) that if klass has been NULL, then
  67       // this has been a mirror for a primitive type that we do not need to follow
  68       // as they are always strong roots.
  69       // However, we might get across a klass that just changed during CMS concurrent
  70       // marking if allocation occurred in the old generation.
  71       // This is benign here, as we keep alive all CLDs that were loaded during the
  72       // CMS concurrent phase in the class loading, i.e. they will be iterated over
  73       // and kept alive during remark.
  74       // assert(java_lang_Class::is_primitive(obj), "Sanity check");
  75     }
  76   }
  77 
  78   oop_oop_iterate_statics<T>(obj, closure);
  79 }
  80 
  81 template <typename T, class OopClosureType>
  82 void InstanceMirrorKlass::oop_oop_iterate_reverse(oop obj, OopClosureType* closure) {
  83   InstanceKlass::oop_oop_iterate_reverse<T>(obj, closure);
  84 
  85   InstanceMirrorKlass::oop_oop_iterate_statics<T>(obj, closure);
  86 }
  87 
  88 template <typename T, class OopClosureType>
  89 void InstanceMirrorKlass::oop_oop_iterate_statics_bounded(oop obj,
  90                                                           OopClosureType* closure,
  91                                                           MemRegion mr) {
  92   T* p   = (T*)start_of_static_fields(obj);
  93   T* end = p + java_lang_Class::static_oop_field_count_raw(obj);
  94 
  95   T* const l   = (T*)mr.start();
  96   T* const h   = (T*)mr.end();
  97   assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 &&
  98          mask_bits((intptr_t)h, sizeof(T)-1) == 0,
  99          "bounded region must be properly aligned");
 100 
 101   if (p < l) {
 102     p = l;
 103   }
 104   if (end > h) {
 105     end = h;
 106   }
 107 
 108   for (;p < end; ++p) {
 109     Devirtualizer::do_oop(closure, p);
 110   }
 111 }
 112 
 113 template <typename T, class OopClosureType>
 114 void InstanceMirrorKlass::oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr) {
 115   InstanceKlass::oop_oop_iterate_bounded<T>(obj, closure, mr);
 116 
 117   if (Devirtualizer::do_metadata(closure)) {
 118     if (mr.contains(obj)) {
 119       Klass* klass = java_lang_Class::as_Klass_raw(obj);
 120       // We'll get NULL for primitive mirrors.
 121       if (klass != NULL) {
 122         Devirtualizer::do_klass(closure, klass);
 123       }
 124     }
 125   }
 126 
 127   oop_oop_iterate_statics_bounded<T>(obj, closure, mr);
 128 }
 129 
 130 #endif // SHARE_OOPS_INSTANCEMIRRORKLASS_INLINE_HPP