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#define SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP
#include "gc/shenandoah/shenandoahForwarding.hpp"
#include "gc/shenandoah/shenandoahAsserts.hpp"
#include "oops/markWord.hpp"
#include "runtime/javaThread.hpp"
inline oop ShenandoahForwarding::get_forwardee_raw(oop obj) {
shenandoah_assert_in_heap_bounds(nullptr, obj);
return get_forwardee_raw_unchecked(obj);
}
inline oop ShenandoahForwarding::get_forwardee_raw_unchecked(oop obj) {
// JVMTI and JFR code use mark words for marking objects for their needs.
// On this path, we can encounter the "marked" object, but with null
// fwdptr. That object is still not forwarded, and we need to return
// the object itself.
markWord mark = obj->mark();
if (mark.is_marked()) {
! HeapWord* fwdptr = (HeapWord*) mark.clear_lock_bits().to_pointer();
if (fwdptr != nullptr) {
return cast_to_oop(fwdptr);
}
}
return obj;
#define SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP
#include "gc/shenandoah/shenandoahForwarding.hpp"
#include "gc/shenandoah/shenandoahAsserts.hpp"
+ #include "oops/klass.hpp"
#include "oops/markWord.hpp"
#include "runtime/javaThread.hpp"
inline oop ShenandoahForwarding::get_forwardee_raw(oop obj) {
shenandoah_assert_in_heap_bounds(nullptr, obj);
return get_forwardee_raw_unchecked(obj);
}
+ static HeapWord* to_forwardee(markWord mark) {
+ return reinterpret_cast<HeapWord*>(mark.value() & ~(markWord::lock_mask_in_place | markWord::self_fwd_mask_in_place));
+ }
inline oop ShenandoahForwarding::get_forwardee_raw_unchecked(oop obj) {
// JVMTI and JFR code use mark words for marking objects for their needs.
// On this path, we can encounter the "marked" object, but with null
// fwdptr. That object is still not forwarded, and we need to return
// the object itself.
markWord mark = obj->mark();
if (mark.is_marked()) {
! HeapWord* fwdptr = to_forwardee(mark);
if (fwdptr != nullptr) {
return cast_to_oop(fwdptr);
}
}
return obj;
shenandoah_assert_correct(nullptr, obj);
assert(Thread::current()->is_Java_thread(), "Must be a mutator thread");
markWord mark = obj->mark();
if (mark.is_marked()) {
! HeapWord* fwdptr = (HeapWord*) mark.clear_lock_bits().to_pointer();
assert(fwdptr != nullptr, "Forwarding pointer is never null here");
return cast_to_oop(fwdptr);
} else {
return obj;
}
shenandoah_assert_correct(nullptr, obj);
assert(Thread::current()->is_Java_thread(), "Must be a mutator thread");
markWord mark = obj->mark();
if (mark.is_marked()) {
! HeapWord* fwdptr = to_forwardee(mark);
assert(fwdptr != nullptr, "Forwarding pointer is never null here");
return cast_to_oop(fwdptr);
} else {
return obj;
}
inline oop ShenandoahForwarding::get_forwardee(oop obj) {
shenandoah_assert_correct(nullptr, obj);
return get_forwardee_raw_unchecked(obj);
}
inline bool ShenandoahForwarding::is_forwarded(oop obj) {
! return obj->mark().is_marked();
}
inline oop ShenandoahForwarding::try_update_forwardee(oop obj, oop update) {
markWord old_mark = obj->mark();
! if (old_mark.is_marked()) {
! return cast_to_oop(old_mark.clear_lock_bits().to_pointer());
}
markWord new_mark = markWord::encode_pointer_as_mark(update);
markWord prev_mark = obj->cas_set_mark(new_mark, old_mark, memory_order_conservative);
if (prev_mark == old_mark) {
return update;
} else {
! return cast_to_oop(prev_mark.clear_lock_bits().to_pointer());
}
}
inline Klass* ShenandoahForwarding::klass(oop obj) {
if (UseCompactObjectHeaders) {
markWord mark = obj->mark();
if (mark.is_marked()) {
! oop fwd = cast_to_oop(mark.clear_lock_bits().to_pointer());
mark = fwd->mark();
}
return mark.klass();
} else {
return obj->klass();
}
}
inline size_t ShenandoahForwarding::size(oop obj) {
! return obj->size_given_klass(klass(obj));
}
#endif // SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP
inline oop ShenandoahForwarding::get_forwardee(oop obj) {
shenandoah_assert_correct(nullptr, obj);
return get_forwardee_raw_unchecked(obj);
}
+ inline bool ShenandoahForwarding::is_forwarded(markWord m) {
+ return (m.value() & (markWord::lock_mask_in_place | markWord::self_fwd_mask_in_place)) > markWord::monitor_value;
+ }
+
inline bool ShenandoahForwarding::is_forwarded(oop obj) {
! return is_forwarded(obj->mark());
}
inline oop ShenandoahForwarding::try_update_forwardee(oop obj, oop update) {
markWord old_mark = obj->mark();
! if (is_forwarded(old_mark)) {
! return cast_to_oop(to_forwardee(old_mark));
}
markWord new_mark = markWord::encode_pointer_as_mark(update);
+ if (UseCompactObjectHeaders && old_mark.is_hashed_not_expanded()) {
+ new_mark = markWord(new_mark.value() | FWDED_HASH_TRANSITION);
+ }
markWord prev_mark = obj->cas_set_mark(new_mark, old_mark, memory_order_conservative);
if (prev_mark == old_mark) {
return update;
} else {
! return cast_to_oop(to_forwardee(prev_mark));
}
}
inline Klass* ShenandoahForwarding::klass(oop obj) {
if (UseCompactObjectHeaders) {
markWord mark = obj->mark();
if (mark.is_marked()) {
! oop fwd = cast_to_oop(to_forwardee(mark));
mark = fwd->mark();
}
return mark.klass();
} else {
return obj->klass();
}
}
inline size_t ShenandoahForwarding::size(oop obj) {
! markWord mark = obj->mark();
+ if (is_forwarded(mark)) {
+ oop fwd = cast_to_oop(to_forwardee(mark));
+ markWord fwd_mark = fwd->mark();
+ Klass* klass = UseCompactObjectHeaders ? fwd_mark.klass() : fwd->klass();
+ size_t size = fwd->base_size_given_klass(fwd_mark, klass);
+ if (UseCompactObjectHeaders) {
+ if ((mark.value() & FWDED_HASH_TRANSITION) != FWDED_HASH_TRANSITION) {
+ if (fwd_mark.is_expanded() && klass->expand_for_hash(fwd, fwd_mark)) {
+ size = align_object_size(size + 1);
+ }
+ }
+ }
+ return size;
+ } else {
+ Klass* klass = UseCompactObjectHeaders ? mark.klass() : obj->klass();
+ return obj->size_given_mark_and_klass(mark, klass);
+ }
}
#endif // SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP
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