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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef SHARE_OOPS_MARKWORD_INLINE_HPP
#define SHARE_OOPS_MARKWORD_INLINE_HPP

#include "oops/klass.hpp"
#include "oops/markWord.hpp"
#include "runtime/globals.hpp"

// Should this header be preserved during GC?
template <typename KlassProxy>
inline bool markWord::must_be_preserved(KlassProxy klass) const {
  if (UseBiasedLocking) {
    if (has_bias_pattern()) {
      // Will reset bias at end of collection
      // Mark words of biased and currently locked objects are preserved separately
      return false;
    }
    markWord prototype_header = prototype_for_klass(klass);
    if (prototype_header.has_bias_pattern()) {
      // Individual instance which has its bias revoked; must return
      // true for correctness
      return true;
    }
  }
  return (!is_unlocked() || !has_no_hash());
}

// Should this header be preserved in the case of a promotion failure during scavenge?
template <typename KlassProxy>
inline bool markWord::must_be_preserved_for_promotion_failure(KlassProxy klass) const {
  if (UseBiasedLocking) {
    // We don't explicitly save off the mark words of biased and
    // currently-locked objects during scavenges, so if during a
    // promotion failure we encounter either a biased mark word or a
    // klass which still has a biasable prototype header, we have to
    // preserve the mark word. This results in oversaving, but promotion
    // failures are rare, and this avoids adding more complex logic to
    // the scavengers to call new variants of
    // BiasedLocking::preserve_marks() / restore_marks() in the middle
    // of a scavenge when a promotion failure has first been detected.
    if (has_bias_pattern() || prototype_for_klass(klass).has_bias_pattern()) {
      return true;
    }
  }
  return (!is_unlocked() || !has_no_hash());
}

// Same as must_be_preserved_for_promotion_failure().
inline bool markWord::must_be_preserved_for_cms_scavenge(Klass* klass_of_obj_containing_mark) const {
  return must_be_preserved_for_promotion_failure(klass_of_obj_containing_mark);
}

inline markWord markWord::prototype_for_klass(const Klass* klass) {
  markWord prototype_header = klass->prototype_header();
  assert(prototype_header == prototype() || prototype_header.has_bias_pattern(), "corrupt prototype header");

  return prototype_header;
}

#endif // SHARE_OOPS_MARKWORD_INLINE_HPP