inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
volatile HeapWord *dest,
oop compare_value) {
if (UseCompressedOops) {
// encode exchange and compare value from oop to T
narrowOop val = encode_heap_oop(exchange_value);
narrowOop cmp = encode_heap_oop(compare_value);
narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
// decode old from T to oop
return decode_heap_oop(old);
} else {
return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
}
}
void oopDesc::set_klass_to_list_ptr(oop k) {
// This is only to be used during GC, for from-space objects, so no
// barrier is needed.
if (UseCompressedClassPointers) {
_metadata._compressed_klass = (narrowKlass)encode_heap_oop(k); // may be null (parnew overflow handling)
} else {
_metadata._klass = (Klass*)(address)k;
}
}
inline void oopDesc::set_klass_to_list_ptr(oop k) {
// This is only to be used during GC, for from-space objects, so no
// barrier is needed.
if (UseCompressedOops) {
_metadata._compressed_klass = encode_heap_oop(k); // may be null (parnew overflow handling)
} else {
_metadata._klass = (klassOop)k;
}
}
inline void oopDesc::release_encode_store_heap_oop(
volatile narrowOop* p, oop v) {
OrderAccess::release_store(p, encode_heap_oop(v));
}
// Encode and store a heap oop allowing for null.
inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
*p = encode_heap_oop(v);
}