src/hotspot/share/gc/shared/accessBarrierSupport.hpp
author stefank
Fri, 06 Apr 2018 11:37:31 +0200
changeset 49710 f67333fc42bd
parent 47998 fb0275c320a0
child 53244 9807daeb47c4
permissions -rw-r--r--
8200737: Move GC code out of Arguments::check_vm_args_consistency into GCArguments Reviewed-by: sjohanss, pliden

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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#ifndef SHARE_VM_GC_SHARED_ACCESSBARRIERSUPPORT_HPP
#define SHARE_VM_GC_SHARED_ACCESSBARRIERSUPPORT_HPP

#include "memory/allocation.hpp"
#include "oops/access.hpp"

class AccessBarrierSupport: AllStatic {
private:
  static DecoratorSet resolve_unknown_oop_ref_strength(DecoratorSet decorators, oop base, ptrdiff_t offset);

public:
  // Some collectors, like G1, needs to keep referents alive when loading them.
  // Therefore, for APIs that accept unknown oop ref strength (e.g. unsafe),
  // we need to dynamically find out if a given field is on a java.lang.ref.Reference object.
  // and in that case what strength it has.
  template<DecoratorSet decorators>
  static DecoratorSet resolve_possibly_unknown_oop_ref_strength(oop base, ptrdiff_t offset);
};

#endif // SHARE_VM_GC_SHARED_ACCESSBARRIERSUPPORT_HPP