< prev index next > src/hotspot/share/oops/oop.inline.hpp
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#include "memory/universe.hpp"
#include "memory/iterator.inline.hpp"
#include "oops/access.inline.hpp"
#include "oops/arrayKlass.hpp"
#include "oops/arrayOop.hpp"
+ #include "oops/compressedKlass.inline.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/instanceKlass.hpp"
- #include "oops/markWord.hpp"
+ #include "oops/markWord.inline.hpp"
#include "oops/oopsHierarchy.hpp"
#include "runtime/atomic.hpp"
#include "runtime/globals.hpp"
+ #include "runtime/objectMonitor.inline.hpp"
+ #include "runtime/safepoint.hpp"
+ #include "runtime/synchronizer.hpp"
#include "utilities/align.hpp"
#include "utilities/debug.hpp"
#include "utilities/macros.hpp"
#include "utilities/globalDefinitions.hpp"
void oopDesc::release_set_mark(markWord m) {
Atomic::release_store(&_mark, m);
}
+ 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) {
return Atomic::cmpxchg(&_mark, old_mark, new_mark);
}
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(UseFastLocking, "Only safe with fast-locking");
+ markWord hdr = mark();
+ if (hdr.has_monitor()) {
+ ObjectMonitor* monitor = hdr.monitor();
+ return monitor->header();
+ }
+ return hdr;
+ }
+
void oopDesc::init_mark() {
+ #ifdef _LP64
+ if (UseCompactObjectHeaders) {
+ markWord header = resolve_mark();
+ assert(UseCompressedClassPointers, "expect compressed klass pointers");
+ set_mark(markWord((header.value() & markWord::klass_mask_in_place) | markWord::prototype().value()));
+ } else
+ #endif
set_mark(markWord::prototype());
}
Klass* oopDesc::klass() const {
- if (UseCompressedClassPointers) {
+ #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 {
- return _metadata._klass;
- }
+ } else
+ #endif
+ return _metadata._klass;
}
Klass* oopDesc::klass_or_null() const {
- if (UseCompressedClassPointers) {
+ #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 {
- return _metadata._klass;
- }
+ } else
+ #endif
+ 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);
- }
+ #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);
}
Klass* oopDesc::klass_raw() const {
- if (UseCompressedClassPointers) {
- return CompressedKlassPointers::decode_raw(_metadata._compressed_klass);
- } else {
- return _metadata._klass;
- }
+ return klass();
}
void oopDesc::set_klass(Klass* k) {
- assert(Universe::is_bootstrapping() || (k != nullptr && k->is_klass()), "incorrect Klass");
+ 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 != nullptr && k->is_klass()), "incorrect Klass");
+ 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);
}
}
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;
}
}
// 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 reversible");
+ assert(forwardee(m) == p, "encoding must be reversable");
+ set_mark(m);
+ }
+
+ void oopDesc::forward_to_self() {
+ #ifdef _LP64
+ verify_forwardee(this);
+ markWord m = mark();
+ // If mark is displaced, we need to preserve the Klass* from real header.
+ 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 reversable");
set_mark(m);
+ #else
+ forward_to(oop(this));
+ #endif
}
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 reversible");
+ assert(forwardee(m) == p, "encoding must be reversable");
markWord old_mark = cas_set_mark(m, compare, order);
if (old_mark == compare) {
return nullptr;
} else {
- return cast_to_oop(old_mark.decode_pointer());
+ return forwardee(old_mark);
}
}
+ oop oopDesc::forward_to_self_atomic(markWord compare, atomic_memory_order order) {
+ #ifdef _LP64
+ verify_forwardee(this);
+ markWord m = compare;
+ // If mark is displaced, we need to preserve the Klass* from real header.
+ 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 reversable");
+ markWord old_mark = cas_set_mark(m, compare, order);
+ if (old_mark == compare) {
+ return NULL;
+ } else {
+ assert(old_mark.is_marked(), "must be marked here");
+ return forwardee(old_mark);
+ }
+ #else
+ return forward_to_atomic(oop(this), compare, order);
+ #endif
+ }
+
// 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 {
- assert(is_forwarded(), "only decode when actually forwarded");
- return cast_to_oop(mark().decode_pointer());
+ return forwardee(mark());
+ }
+
+ oop oopDesc::forwardee(markWord header) const {
+ assert(header.is_marked(), "must be forwarded");
+ #ifdef _LP64
+ if (header.self_forwarded()) {
+ return cast_to_oop(this);
+ } else
+ #endif
+ {
+ assert(header.is_marked(), "only decode when actually forwarded");
+ return cast_to_oop(header.decode_pointer());
+ }
}
// The following method needs to be MT safe.
uint oopDesc::age() const {
assert(!mark().is_marked(), "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 == nullptr || obj->klass()->is_subtype_of(klass);
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