Thu, 07 Apr 2011 09:53:20 -0700
7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error
Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.
Reviewed-by: kvn, iveresov, never, tonyp, dholmes
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25 #ifndef SHARE_VM_OOPS_TYPEARRAYKLASSKLASS_HPP
26 #define SHARE_VM_OOPS_TYPEARRAYKLASSKLASS_HPP
28 #include "oops/arrayKlassKlass.hpp"
29 #include "oops/typeArrayKlass.hpp"
31 // A typeArrayKlassKlass is the klass of a typeArrayKlass
33 class typeArrayKlassKlass : public arrayKlassKlass {
34 public:
35 // Testing
36 bool oop_is_typeArrayKlass() const { return true; }
38 // Dispatched operation
39 int oop_size(oop obj) const { return typeArrayKlass::cast(klassOop(obj))->object_size(); }
40 int klass_oop_size() const { return object_size(); }
42 // Allocation
43 DEFINE_ALLOCATE_PERMANENT(typeArrayKlassKlass);
44 static klassOop create_klass(TRAPS);
46 // Casting from klassOop
47 static typeArrayKlassKlass* cast(klassOop k) {
48 assert(k->klass_part()->oop_is_klass(), "cast to typeArrayKlassKlass");
49 return (typeArrayKlassKlass*) k->klass_part();
50 }
52 // Sizing
53 static int header_size() { return oopDesc::header_size() + sizeof(typeArrayKlassKlass)/HeapWordSize; }
54 int object_size() const { return align_object_size(header_size()); }
56 public:
57 // Printing
58 void oop_print_value_on(oop obj, outputStream* st);
59 #ifndef PRODUCT
60 void oop_print_on(oop obj, outputStream* st);
61 #endif //PRODUCT
63 const char* internal_name() const;
64 };
66 #endif // SHARE_VM_OOPS_TYPEARRAYKLASSKLASS_HPP