< prev index next > src/hotspot/share/oops/oop.inline.hpp
Print this page
#include "oops/compressedOops.inline.hpp"
#include "oops/markWord.inline.hpp"
#include "oops/oopsHierarchy.hpp"
#include "runtime/atomic.hpp"
#include "runtime/globals.hpp"
+ #include "runtime/safepoint.hpp"
+ #include "runtime/objectMonitor.inline.hpp"
#include "utilities/align.hpp"
#include "utilities/debug.hpp"
#include "utilities/macros.hpp"
#include "utilities/globalDefinitions.hpp"
markWord oopDesc::mark() const {
uintptr_t v = HeapAccess<MO_RELAXED>::load_at(as_oop(), mark_offset_in_bytes());
return markWord(v);
}
+ markWord oopDesc::mark_acquire() const {
+ return Atomic::load_acquire(&_mark);
+ }
markWord* oopDesc::mark_addr() const {
return (markWord*) &_mark;
}
void oopDesc::set_mark(markWord m) {
void oopDesc::release_set_mark(markWord m) {
HeapAccess<MO_RELEASE>::store_at(as_oop(), mark_offset_in_bytes(), m.value());
}
markWord oopDesc::cas_set_mark(markWord new_mark, markWord old_mark) {
uintptr_t v = HeapAccess<>::atomic_cmpxchg_at(as_oop(), mark_offset_in_bytes(), old_mark.value(), new_mark.value());
return markWord(v);
}
markWord oopDesc::cas_set_mark(markWord new_mark, markWord old_mark, atomic_memory_order order) {
return Atomic::cmpxchg(&_mark, old_mark, new_mark, order);
}
void oopDesc::init_mark() {
set_mark(markWord::prototype_for_klass(klass()));
}
Klass* oopDesc::klass() const {
! if (UseCompressedClassPointers) {
return CompressedKlassPointers::decode_not_null(_metadata._compressed_klass);
! } else {
! return _metadata._klass;
! }
}
Klass* oopDesc::klass_or_null() const {
! if (UseCompressedClassPointers) {
return CompressedKlassPointers::decode(_metadata._compressed_klass);
! } else {
! return _metadata._klass;
! }
}
Klass* oopDesc::klass_or_null_acquire() const {
! if (UseCompressedClassPointers) {
! narrowKlass nklass = Atomic::load_acquire(&_metadata._compressed_klass);
! return CompressedKlassPointers::decode(nklass);
! } else {
! return Atomic::load_acquire(&_metadata._klass);
! }
}
void oopDesc::set_klass(Klass* k) {
assert(Universe::is_bootstrapping() || (k != NULL && k->is_klass()), "incorrect Klass");
if (UseCompressedClassPointers) {
_metadata._compressed_klass = CompressedKlassPointers::encode_not_null(k);
} else {
_metadata._klass = k;
}
}
void oopDesc::release_set_klass(HeapWord* mem, Klass* k) {
assert(Universe::is_bootstrapping() || (k != NULL && k->is_klass()), "incorrect Klass");
char* raw_mem = ((char*)mem + klass_offset_in_bytes());
if (UseCompressedClassPointers) {
Atomic::release_store((narrowKlass*)raw_mem,
CompressedKlassPointers::encode_not_null(k));
} else {
Atomic::release_store((Klass**)raw_mem, k);
}
}
int oopDesc::klass_gap() const {
return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
}
void oopDesc::set_klass_gap(HeapWord* mem, int v) {
if (UseCompressedClassPointers) {
*(int*)(((char*)mem) + klass_gap_offset_in_bytes()) = v;
}
}
void oopDesc::set_klass_gap(int v) {
set_klass_gap((HeapWord*)this, v);
}
bool oopDesc::is_a(Klass* k) const {
return klass()->is_subtype_of(k);
void oopDesc::release_set_mark(markWord m) {
HeapAccess<MO_RELEASE>::store_at(as_oop(), mark_offset_in_bytes(), m.value());
}
+ void oopDesc::release_set_mark(HeapWord* mem, markWord m) {
+ Atomic::release_store((markWord*)(((char*)mem) + mark_offset_in_bytes()), m);
+ }
+
markWord oopDesc::cas_set_mark(markWord new_mark, markWord old_mark) {
uintptr_t v = HeapAccess<>::atomic_cmpxchg_at(as_oop(), mark_offset_in_bytes(), old_mark.value(), new_mark.value());
return markWord(v);
}
markWord oopDesc::cas_set_mark(markWord new_mark, markWord old_mark, atomic_memory_order order) {
return Atomic::cmpxchg(&_mark, old_mark, new_mark, order);
}
+ markWord oopDesc::resolve_mark() const {
+ assert(LockingMode != LM_LEGACY, "Not safe with legacy stack-locking");
+ markWord hdr = mark();
+ if (hdr.has_displaced_mark_helper()) {
+ hdr = hdr.displaced_mark_helper();
+ }
+ return hdr;
+ }
+
+ markWord oopDesc::prototype_mark() const {
+ if (UseCompactObjectHeaders) {
+ return klass()->prototype_header();
+ } else {
+ return markWord::prototype();
+ }
+ }
+
void oopDesc::init_mark() {
set_mark(markWord::prototype_for_klass(klass()));
}
Klass* oopDesc::klass() const {
! #ifdef _LP64
+ if (UseCompactObjectHeaders) {
+ assert(UseCompressedClassPointers, "only with compressed class pointers");
+ markWord header = resolve_mark();
+ return header.klass();
+ } else if (UseCompressedClassPointers) {
return CompressedKlassPointers::decode_not_null(_metadata._compressed_klass);
! } else
! #endif
! return _metadata._klass;
}
Klass* oopDesc::klass_or_null() const {
! #ifdef _LP64
+ if (UseCompactObjectHeaders) {
+ assert(UseCompressedClassPointers, "only with compressed class pointers");
+ markWord header = resolve_mark();
+ return header.klass_or_null();
+ } else if (UseCompressedClassPointers) {
return CompressedKlassPointers::decode(_metadata._compressed_klass);
! } else
! #endif
! return _metadata._klass;
}
Klass* oopDesc::klass_or_null_acquire() const {
! #ifdef _LP64
! if (UseCompactObjectHeaders) {
! assert(UseCompressedClassPointers, "only with compressed class pointers");
! markWord header = mark_acquire();
! if (header.has_monitor()) {
! header = header.monitor()->header();
+ }
+ return header.klass_or_null();
+ } else if (UseCompressedClassPointers) {
+ narrowKlass nklass = Atomic::load_acquire(&_metadata._compressed_klass);
+ return CompressedKlassPointers::decode(nklass);
+ } else
+ #endif
+ return Atomic::load_acquire(&_metadata._klass);
}
void oopDesc::set_klass(Klass* k) {
assert(Universe::is_bootstrapping() || (k != NULL && k->is_klass()), "incorrect Klass");
+ assert(!UseCompactObjectHeaders, "don't set Klass* with compact headers");
if (UseCompressedClassPointers) {
_metadata._compressed_klass = CompressedKlassPointers::encode_not_null(k);
} else {
_metadata._klass = k;
}
}
void oopDesc::release_set_klass(HeapWord* mem, Klass* k) {
assert(Universe::is_bootstrapping() || (k != NULL && k->is_klass()), "incorrect Klass");
+ assert(!UseCompactObjectHeaders, "don't set Klass* with compact headers");
char* raw_mem = ((char*)mem + klass_offset_in_bytes());
if (UseCompressedClassPointers) {
Atomic::release_store((narrowKlass*)raw_mem,
CompressedKlassPointers::encode_not_null(k));
} else {
Atomic::release_store((Klass**)raw_mem, k);
}
}
int oopDesc::klass_gap() const {
+ assert(!UseCompactObjectHeaders, "don't get Klass* gap with compact headers");
return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
}
void oopDesc::set_klass_gap(HeapWord* mem, int v) {
+ assert(!UseCompactObjectHeaders, "don't set Klass* gap with compact headers");
if (UseCompressedClassPointers) {
*(int*)(((char*)mem) + klass_gap_offset_in_bytes()) = v;
}
}
void oopDesc::set_klass_gap(int v) {
+ assert(!UseCompactObjectHeaders, "don't set Klass* gap with compact headers");
set_klass_gap((HeapWord*)this, v);
}
bool oopDesc::is_a(Klass* k) const {
return klass()->is_subtype_of(k);
assert(s > 0, "Oop size must be greater than zero, not %d", s);
assert(is_object_aligned(s), "Oop size is not properly aligned: %d", s);
return s;
}
+ #ifdef _LP64
+ Klass* oopDesc::forward_safe_klass_impl(markWord m) const {
+ assert(UseCompactObjectHeaders, "Only get here with compact headers");
+ if (m.is_marked()) {
+ oop fwd = forwardee(m);
+ markWord m2 = fwd->mark();
+ assert(!m2.is_marked() || m2.self_forwarded(), "no double forwarding: this: " PTR_FORMAT " (" INTPTR_FORMAT "), fwd: " PTR_FORMAT " (" INTPTR_FORMAT ")", p2i(this), m.value(), p2i(fwd), m2.value());
+ m = m2;
+ }
+ return m.actual_mark().klass();
+ }
+ #endif
+
+ Klass* oopDesc::forward_safe_klass(markWord m) const {
+ #ifdef _LP64
+ if (UseCompactObjectHeaders) {
+ return forward_safe_klass_impl(m);
+ } else
+ #endif
+ {
+ return klass();
+ }
+ }
+
+ Klass* oopDesc::forward_safe_klass() const {
+ #ifdef _LP64
+ if (UseCompactObjectHeaders) {
+ return forward_safe_klass_impl(mark());
+ } else
+ #endif
+ {
+ return klass();
+ }
+ }
+
+ size_t oopDesc::forward_safe_size() {
+ return size_given_klass(forward_safe_klass());
+ }
+
+ void oopDesc::forward_safe_init_mark() {
+ if (UseCompactObjectHeaders) {
+ set_mark(forward_safe_klass()->prototype_header());
+ } else {
+ init_mark();
+ }
+ }
+
bool oopDesc::is_instance() const { return klass()->is_instance_klass(); }
bool oopDesc::is_array() const { return klass()->is_array_klass(); }
bool oopDesc::is_objArray() const { return klass()->is_objArray_klass(); }
bool oopDesc::is_typeArray() const { return klass()->is_typeArray_klass(); }
return mark().is_marked();
}
// Used by scavengers
void oopDesc::forward_to(oop p) {
verify_forwardee(p);
markWord m = markWord::encode_pointer_as_mark(p);
! assert(m.decode_pointer() == p, "encoding must be reversable");
set_mark(m);
}
! // Used by parallel scavengers
! bool oopDesc::cas_forward_to(oop p, markWord compare, atomic_memory_order order) {
! verify_forwardee(p);
! markWord m = markWord::encode_pointer_as_mark(p);
! assert(m.decode_pointer() == p, "encoding must be reversable");
! return cas_set_mark(m, compare, order) == compare;
}
oop oopDesc::forward_to_atomic(oop p, markWord compare, atomic_memory_order order) {
verify_forwardee(p);
markWord m = markWord::encode_pointer_as_mark(p);
! assert(m.decode_pointer() == p, "encoding must be reversable");
markWord old_mark = cas_set_mark(m, compare, order);
if (old_mark == compare) {
return NULL;
} else {
! return cast_to_oop(old_mark.decode_pointer());
}
}
// Note that the forwardee is not the same thing as the displaced_mark.
// The forwardee is used when copying during scavenge and mark-sweep.
// It does need to clear the low two locking- and GC-related bits.
oop oopDesc::forwardee() const {
! return cast_to_oop(mark().decode_pointer());
}
// The following method needs to be MT safe.
uint oopDesc::age() const {
assert(!is_forwarded(), "Attempt to read age from forwarded mark");
return mark().is_marked();
}
// Used by scavengers
void oopDesc::forward_to(oop p) {
+ assert(p != cast_to_oop(this) || !UseAltGCForwarding, "Must not be called with self-forwarding");
verify_forwardee(p);
markWord m = markWord::encode_pointer_as_mark(p);
! assert(forwardee(m) == p, "encoding must be reversable");
set_mark(m);
}
! void oopDesc::forward_to_self() {
! #ifdef _LP64
! if (UseAltGCForwarding) {
! markWord m = mark();
! // If mark is displaced, we need to preserve the real header during GC.
! // It will be restored to the displaced header after GC.
+ assert(SafepointSynchronize::is_at_safepoint(), "we can only safely fetch the displaced header at safepoint");
+ if (m.has_displaced_mark_helper()) {
+ m = m.displaced_mark_helper();
+ }
+ m = m.set_self_forwarded();
+ assert(forwardee(m) == cast_to_oop(this), "encoding must be reversible");
+ set_mark(m);
+ } else
+ #endif
+ {
+ forward_to(oop(this));
+ }
}
oop oopDesc::forward_to_atomic(oop p, markWord compare, atomic_memory_order order) {
+ assert(p != cast_to_oop(this) || !UseAltGCForwarding, "Must not be called with self-forwarding");
verify_forwardee(p);
markWord m = markWord::encode_pointer_as_mark(p);
! assert(forwardee(m) == p, "encoding must be reversable");
markWord old_mark = cas_set_mark(m, compare, order);
if (old_mark == compare) {
return NULL;
} else {
! return forwardee(old_mark);
+ }
+ }
+
+ oop oopDesc::forward_to_self_atomic(markWord compare, atomic_memory_order order) {
+ #ifdef _LP64
+ if (UseAltGCForwarding) {
+ markWord m = compare;
+ // If mark is displaced, we need to preserve the real header during GC.
+ // It will be restored to the displaced header after GC.
+ assert(SafepointSynchronize::is_at_safepoint(), "we can only safely fetch the displaced header at safepoint");
+ if (m.has_displaced_mark_helper()) {
+ m = m.displaced_mark_helper();
+ }
+ m = m.set_self_forwarded();
+ assert(forwardee(m) == cast_to_oop(this), "encoding must be reversible");
+ markWord old_mark = cas_set_mark(m, compare, order);
+ if (old_mark == compare) {
+ return nullptr;
+ } else {
+ assert(old_mark.is_marked(), "must be marked here");
+ return forwardee(old_mark);
+ }
+ } else
+ #endif
+ {
+ return forward_to_atomic(cast_to_oop(this), compare, order);
+ }
+ }
+
+ oop oopDesc::forwardee(markWord header) const {
+ assert(header.is_marked(), "only decode when actually forwarded");
+ #ifdef _LP64
+ if (header.self_forwarded()) {
+ return cast_to_oop(this);
+ } else
+ #endif
+ {
+ return cast_to_oop(header.decode_pointer());
}
}
// Note that the forwardee is not the same thing as the displaced_mark.
// The forwardee is used when copying during scavenge and mark-sweep.
// It does need to clear the low two locking- and GC-related bits.
oop oopDesc::forwardee() const {
! return forwardee(mark());
}
// The following method needs to be MT safe.
uint oopDesc::age() const {
assert(!is_forwarded(), "Attempt to read age from forwarded mark");
oop_iterate_backwards(cl, klass());
}
template <typename OopClosureType>
void oopDesc::oop_iterate_backwards(OopClosureType* cl, Klass* k) {
! assert(k == klass(), "wrong klass");
OopIteratorClosureDispatch::oop_oop_iterate_backwards(cl, this, k);
}
bool oopDesc::is_instanceof_or_null(oop obj, Klass* klass) {
return obj == NULL || obj->klass()->is_subtype_of(klass);
oop_iterate_backwards(cl, klass());
}
template <typename OopClosureType>
void oopDesc::oop_iterate_backwards(OopClosureType* cl, Klass* k) {
! assert(UseCompactObjectHeaders || k == klass(), "wrong klass");
OopIteratorClosureDispatch::oop_oop_iterate_backwards(cl, this, k);
}
bool oopDesc::is_instanceof_or_null(oop obj, Klass* klass) {
return obj == NULL || obj->klass()->is_subtype_of(klass);
< prev index next >