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  23 
  24 #ifndef SHARE_OOPS_INSTANCEMIRRORKLASS_INLINE_HPP
  25 #define SHARE_OOPS_INSTANCEMIRRORKLASS_INLINE_HPP
  26 
  27 #include "classfile/javaClasses.hpp"
  28 #include "oops/instanceKlass.inline.hpp"
  29 #include "oops/instanceMirrorKlass.hpp"
  30 #include "oops/klass.hpp"
  31 #include "oops/oop.inline.hpp"
  32 #include "utilities/debug.hpp"
  33 #include "utilities/globalDefinitions.hpp"
  34 #include "utilities/macros.hpp"
  35 
  36 template <typename T, class OopClosureType>
  37 void InstanceMirrorKlass::oop_oop_iterate_statics(oop obj, OopClosureType* closure) {
  38   T* p         = (T*)start_of_static_fields(obj);
  39   T* const end = p + java_lang_Class::static_oop_field_count_raw(obj);
  40 
  41   for (; p < end; ++p) {
  42     Devirtualizer::do_oop(closure, p);
  43   }
  44 }
  45 
  46 template <typename T, class OopClosureType>
  47 void InstanceMirrorKlass::oop_oop_iterate(oop obj, OopClosureType* closure) {
  48   InstanceKlass::oop_oop_iterate<T>(obj, closure);
  49 
  50   if (Devirtualizer::do_metadata(closure)) {
  51     Klass* klass = java_lang_Class::as_Klass_raw(obj);
  52     // We'll get NULL for primitive mirrors.
  53     if (klass != NULL) {
  54       if (klass->is_instance_klass() && klass->class_loader_data()->is_shortlived()) {
  55         // A weak nonfindable or an unsafe anonymous class doesn't have its own class loader,
  56         // so when handling the java mirror for the class we need to make sure its class
  57         // loader data is claimed, this is done by calling do_cld explicitly.
  58         // For non-anonymous classes the call to do_cld is made when the class
  59         // loader itself is handled.
  60         Devirtualizer::do_cld(closure, klass->class_loader_data());
  61       } else {
  62         Devirtualizer::do_klass(closure, klass);
  63       }
  64     } else {
  65       // We would like to assert here (as below) that if klass has been NULL, then
  66       // this has been a mirror for a primitive type that we do not need to follow
  67       // as they are always strong roots.
  68       // However, we might get across a klass that just changed during CMS concurrent
  69       // marking if allocation occurred in the old generation.
  70       // This is benign here, as we keep alive all CLDs that were loaded during the
  71       // CMS concurrent phase in the class loading, i.e. they will be iterated over
  72       // and kept alive during remark.
  73       // assert(java_lang_Class::is_primitive(obj), "Sanity check");
  74     }
  75   }
  76 
  77   oop_oop_iterate_statics<T>(obj, closure);
  78 }
  79 
  80 template <typename T, class OopClosureType>
  81 void InstanceMirrorKlass::oop_oop_iterate_reverse(oop obj, OopClosureType* closure) {
  82   InstanceKlass::oop_oop_iterate_reverse<T>(obj, closure);
  83 
  84   InstanceMirrorKlass::oop_oop_iterate_statics<T>(obj, closure);
  85 }
  86 
  87 template <typename T, class OopClosureType>
  88 void InstanceMirrorKlass::oop_oop_iterate_statics_bounded(oop obj,
  89                                                           OopClosureType* closure,
  90                                                           MemRegion mr) {
  91   T* p   = (T*)start_of_static_fields(obj);
  92   T* end = p + java_lang_Class::static_oop_field_count_raw(obj);
  93 
  94   T* const l   = (T*)mr.start();
  95   T* const h   = (T*)mr.end();
  96   assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 &&
  97          mask_bits((intptr_t)h, sizeof(T)-1) == 0,
  98          "bounded region must be properly aligned");
  99 
 100   if (p < l) {
 101     p = l;
 102   }
 103   if (end > h) {
 104     end = h;
 105   }
 106 
 107   for (;p < end; ++p) {
 108     Devirtualizer::do_oop(closure, p);
 109   }
 110 }
 111 
 112 template <typename T, class OopClosureType>
 113 void InstanceMirrorKlass::oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr) {
 114   InstanceKlass::oop_oop_iterate_bounded<T>(obj, closure, mr);
 115 
 116   if (Devirtualizer::do_metadata(closure)) {
 117     if (mr.contains(obj)) {
 118       Klass* klass = java_lang_Class::as_Klass_raw(obj);
 119       // We'll get NULL for primitive mirrors.
 120       if (klass != NULL) {
 121         Devirtualizer::do_klass(closure, klass);
 122       }
 123     }
 124   }
 125 
 126   oop_oop_iterate_statics_bounded<T>(obj, closure, mr);
 127 }
 128 
 129 #endif // SHARE_OOPS_INSTANCEMIRRORKLASS_INLINE_HPP