klass.inline.hpp

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#ifndef SHARE_OOPS_KLASS_INLINE_HPP
#define SHARE_OOPS_KLASS_INLINE_HPP

#include "oops/klass.hpp"

#include "classfile/classLoaderData.inline.hpp"
#include "oops/klassVtable.hpp"
#include "oops/markWord.hpp"

// This loads the klass's holder as a phantom. This is useful when a weak Klass
// pointer has been "peeked" and then must be kept alive before it may
// be used safely.  All uses of klass_holder need to apply the appropriate barriers,
// except during GC.
inline oop Klass::klass_holder() const {
  return class_loader_data()->holder_phantom();
}

inline bool Klass::is_non_strong_hidden() const {
  return access_flags().is_hidden_class() &&
         class_loader_data()->has_class_mirror_holder();
}

// Iff the class loader (or mirror for non-strong hidden classes) is alive the
// Klass is considered alive. This is safe to call before the CLD is marked as
// unloading, and hence during concurrent class unloading.
inline bool Klass::is_loader_alive() const {
  return class_loader_data()->is_alive();
}

inline void Klass::set_prototype_header(markWord header) {
  assert(!header.has_bias_pattern() || is_instance_klass(), "biased locking currently only supported for Java instances");
  _prototype_header = header;
}

inline oop Klass::java_mirror() const {
  return _java_mirror.resolve();
}

inline klassVtable Klass::vtable() const {
  return klassVtable(const_cast<Klass*>(this), start_of_vtable(), vtable_length() / vtableEntry::size());
}

inline oop Klass::class_loader() const {
  return class_loader_data()->class_loader();
}

inline vtableEntry* Klass::start_of_vtable() const {
  return (vtableEntry*) ((address)this + in_bytes(vtable_start_offset()));
}

inline ByteSize Klass::vtable_start_offset() {
  return in_ByteSize(InstanceKlass::header_size() * wordSize);
}

#endif // SHARE_OOPS_KLASS_INLINE_HPP