jdk-sandbox: comparison hotspot/src/share/vm/memory/referenceProcessor.cpp

equal deleted inserted replaced

-:f4edb0d9f109
+:21d113ecbf6a
 # include "incls/_referenceProcessor.cpp.incl"
 // List of discovered references.
 class DiscoveredList {
 public:
-DiscoveredList() : _head(NULL), _len(0) { }
+DiscoveredList() : _len(0), _compressed_head(0), _oop_head(NULL) { }
-oop    head() const           { return _head; }
+oop head() const     {
-oop*   head_ptr()             { return &_head; }
+return UseCompressedOops ?  oopDesc::decode_heap_oop_not_null(_compressed_head) :
-void   set_head(oop o)        { _head = o; }
+_oop_head;
-bool   empty() const          { return _head == ReferenceProcessor::_sentinelRef; }
+}
+HeapWord* adr_head() {
+return UseCompressedOops ? (HeapWord*)&_compressed_head :
+(HeapWord*)&_oop_head;
+}
+void   set_head(oop o) {
+if (UseCompressedOops) {
+// Must compress the head ptr.
+_compressed_head = oopDesc::encode_heap_oop_not_null(o);
+} else {
+_oop_head = o;
+}
+}
+bool   empty() const          { return head() == ReferenceProcessor::sentinel_ref(); }
 size_t length()               { return _len; }
 void   set_length(size_t len) { _len = len; }
 private:
+// Set value depending on UseCompressedOops. This could be a template class
+// but then we have to fix all the instantiations and declarations that use this class.
+oop       _oop_head;
+narrowOop _compressed_head;
 size_t _len;
-oop   _head;
 };
 oop  ReferenceProcessor::_sentinelRef = NULL;
 const int subclasses_of_ref = REF_PHANTOM - REF_OTHER;
 void referenceProcessor_init() {
 ReferenceProcessor::init_statics();
 }
 void ReferenceProcessor::init_statics() {
-assert(_sentinelRef == NULL, "should be initialized precsiely once");
+assert(_sentinelRef == NULL, "should be initialized precisely once");
 EXCEPTION_MARK;
 _sentinelRef = instanceKlass::cast(
-SystemDictionary::object_klass())->
+SystemDictionary::reference_klass())->
 allocate_permanent_instance(THREAD);
 // Initialize the master soft ref clock.
 java_lang_ref_SoftReference::set_clock(os::javaTimeMillis());
 if (HAS_PENDING_EXCEPTION) {
 guarantee(RefDiscoveryPolicy == ReferenceBasedDiscovery ||
 RefDiscoveryPolicy == ReferentBasedDiscovery,
 "Unrecongnized RefDiscoveryPolicy");
 }
+ReferenceProcessor*
-ReferenceProcessor* ReferenceProcessor::create_ref_processor(
+ReferenceProcessor::create_ref_processor(MemRegion          span,
-MemRegion          span,
+bool               atomic_discovery,
-bool               atomic_discovery,
+bool               mt_discovery,
-bool               mt_discovery,
+BoolObjectClosure* is_alive_non_header,
-BoolObjectClosure* is_alive_non_header,
+int                parallel_gc_threads,
-int                parallel_gc_threads,
+bool               mt_processing) {
-bool               mt_processing)
-{
 int mt_degree = 1;
 if (parallel_gc_threads > 1) {
 mt_degree = parallel_gc_threads;
 }
 ReferenceProcessor* rp =
 }
 rp->set_is_alive_non_header(is_alive_non_header);
 return rp;
 }
 ReferenceProcessor::ReferenceProcessor(MemRegion span,
-bool atomic_discovery, bool mt_discovery, int mt_degree,
+bool      atomic_discovery,
-bool mt_processing) :
+bool      mt_discovery,
+int       mt_degree,
+bool      mt_processing) :
 _discovering_refs(false),
 _enqueuing_is_done(false),
 _is_alive_non_header(NULL),
 _processing_is_mt(mt_processing),
 _next_id(0)
 vm_exit_during_initialization("Could not allocated RefProc Array");
 }
 _discoveredWeakRefs    = &_discoveredSoftRefs[_num_q];
 _discoveredFinalRefs   = &_discoveredWeakRefs[_num_q];
 _discoveredPhantomRefs = &_discoveredFinalRefs[_num_q];
-assert(_sentinelRef != NULL, "_sentinelRef is NULL");
+assert(sentinel_ref() != NULL, "_sentinelRef is NULL");
 // Initialized all entries to _sentinelRef
 for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
-_discoveredSoftRefs[i].set_head(_sentinelRef);
+_discoveredSoftRefs[i].set_head(sentinel_ref());
 _discoveredSoftRefs[i].set_length(0);
 }
 }
 #ifndef PRODUCT
 }
 #endif
 void ReferenceProcessor::weak_oops_do(OopClosure* f) {
 for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
-f->do_oop(_discoveredSoftRefs[i].head_ptr());
+if (UseCompressedOops) {
+f->do_oop((narrowOop*)_discoveredSoftRefs[i].adr_head());
+} else {
+f->do_oop((oop*)_discoveredSoftRefs[i].adr_head());
+}
 }
 }
 void ReferenceProcessor::oops_do(OopClosure* f) {
-f->do_oop(&_sentinelRef);
+f->do_oop(adr_sentinel_ref());
 }
-void ReferenceProcessor::update_soft_ref_master_clock()
+void ReferenceProcessor::update_soft_ref_master_clock() {
-{
 // Update (advance) the soft ref master clock field. This must be done
 // after processing the soft ref list.
 jlong now = os::javaTimeMillis();
 jlong clock = java_lang_ref_SoftReference::clock();
 NOT_PRODUCT(
 }
 // Else leave clock stalled at its old value until time progresses
 // past clock value.
 }
+void ReferenceProcessor::process_discovered_references(
-void
-ReferenceProcessor::process_discovered_references(
 ReferencePolicy*             policy,
 BoolObjectClosure*           is_alive,
 OopClosure*                  keep_alive,
 VoidClosure*                 complete_gc,
 AbstractRefProcTaskExecutor* task_executor) {
 }
 process_phaseJNI(is_alive, keep_alive, complete_gc);
 }
 }
 #ifndef PRODUCT
 // Calculate the number of jni handles.
-unsigned int ReferenceProcessor::count_jni_refs()
+uint ReferenceProcessor::count_jni_refs() {
-{
 class AlwaysAliveClosure: public BoolObjectClosure {
 public:
-bool do_object_b(oop obj) { return true; }
+virtual bool do_object_b(oop obj) { return true; }
-void do_object(oop obj) { assert(false, "Don't call"); }
+virtual void do_object(oop obj) { assert(false, "Don't call"); }
 };
 class CountHandleClosure: public OopClosure {
 private:
 int _count;
 public:
 CountHandleClosure(): _count(0) {}
-void do_oop(oop* unused) {
+void do_oop(oop* unused)       { _count++; }
-_count++;
+void do_oop(narrowOop* unused) { ShouldNotReachHere(); }
-}
 int count() { return _count; }
 };
 CountHandleClosure global_handle_count;
 AlwaysAliveClosure always_alive;
 JNIHandles::weak_oops_do(&always_alive, &global_handle_count);
 gclog_or_tty->print(", %u refs", count);
 }
 #endif
 JNIHandles::weak_oops_do(is_alive, keep_alive);
 // Finally remember to keep sentinel around
-keep_alive->do_oop(&_sentinelRef);
+keep_alive->do_oop(adr_sentinel_ref());
 complete_gc->do_void();
 }
-bool ReferenceProcessor::enqueue_discovered_references(AbstractRefProcTaskExecutor* task_executor) {
-NOT_PRODUCT(verify_ok_to_handle_reflists());
+template <class T>
+static bool enqueue_discovered_ref_helper(ReferenceProcessor* ref,
+AbstractRefProcTaskExecutor* task_executor) {
 // Remember old value of pending references list
-oop* pending_list_addr = java_lang_ref_Reference::pending_list_addr();
+T* pending_list_addr = (T*)java_lang_ref_Reference::pending_list_addr();
-oop old_pending_list_value = *pending_list_addr;
+T old_pending_list_value = *pending_list_addr;
 // Enqueue references that are not made active again, and
 // clear the decks for the next collection (cycle).
-enqueue_discovered_reflists(pending_list_addr, task_executor);
+ref->enqueue_discovered_reflists((HeapWord*)pending_list_addr, task_executor);
 // Do the oop-check on pending_list_addr missed in
 // enqueue_discovered_reflist. We should probably
 // do a raw oop_check so that future such idempotent
 // oop_stores relying on the oop-check side-effect
 // may be elided automatically and safely without
 // affecting correctness.
-oop_store(pending_list_addr, *(pending_list_addr));
+oop_store(pending_list_addr, oopDesc::load_decode_heap_oop(pending_list_addr));
 // Stop treating discovered references specially.
-disable_discovery();
+ref->disable_discovery();
 // Return true if new pending references were added
 return old_pending_list_value != *pending_list_addr;
 }
+bool ReferenceProcessor::enqueue_discovered_references(AbstractRefProcTaskExecutor* task_executor) {
+NOT_PRODUCT(verify_ok_to_handle_reflists());
+if (UseCompressedOops) {
+return enqueue_discovered_ref_helper<narrowOop>(this, task_executor);
+} else {
+return enqueue_discovered_ref_helper<oop>(this, task_executor);
+}
+}
 void ReferenceProcessor::enqueue_discovered_reflist(DiscoveredList& refs_list,
-oop* pending_list_addr) {
+HeapWord* pending_list_addr) {
 // Given a list of refs linked through the "discovered" field
 // (java.lang.ref.Reference.discovered) chain them through the
 // "next" field (java.lang.ref.Reference.next) and prepend
 // to the pending list.
 if (TraceReferenceGC && PrintGCDetails) {
 oop obj = refs_list.head();
 // Walk down the list, copying the discovered field into
 // the next field and clearing it (except for the last
 // non-sentinel object which is treated specially to avoid
 // confusion with an active reference).
-while (obj != _sentinelRef) {
+while (obj != sentinel_ref()) {
 assert(obj->is_instanceRef(), "should be reference object");
 oop next = java_lang_ref_Reference::discovered(obj);
 if (TraceReferenceGC && PrintGCDetails) {
-gclog_or_tty->print_cr("  obj " INTPTR_FORMAT "/next " INTPTR_FORMAT,
+gclog_or_tty->print_cr("        obj " INTPTR_FORMAT "/next " INTPTR_FORMAT,
-(oopDesc*) obj, (oopDesc*) next);
+obj, next);
 }
-assert(*java_lang_ref_Reference::next_addr(obj) == NULL,
+assert(java_lang_ref_Reference::next(obj) == NULL,
 "The reference should not be enqueued");
-if (next == _sentinelRef) {  // obj is last
+if (next == sentinel_ref()) {  // obj is last
 // Swap refs_list into pendling_list_addr and
 // set obj's next to what we read from pending_list_addr.
-oop old = (oop)Atomic::xchg_ptr(refs_list.head(), pending_list_addr);
+oop old = oopDesc::atomic_exchange_oop(refs_list.head(), pending_list_addr);
 // Need oop_check on pending_list_addr above;
 // see special oop-check code at the end of
 // enqueue_discovered_reflists() further below.
 if (old == NULL) {
 // obj should be made to point to itself, since
 // Parallel enqueue task
 class RefProcEnqueueTask: public AbstractRefProcTaskExecutor::EnqueueTask {
 public:
 RefProcEnqueueTask(ReferenceProcessor& ref_processor,
 DiscoveredList      discovered_refs[],
-oop*                pending_list_addr,
+HeapWord*           pending_list_addr,
 oop                 sentinel_ref,
 int                 n_queues)
 : EnqueueTask(ref_processor, discovered_refs,
 pending_list_addr, sentinel_ref, n_queues)
 { }
-virtual void work(unsigned int work_id)
+virtual void work(unsigned int work_id) {
-{
 assert(work_id < (unsigned int)_ref_processor.num_q(), "Index out-of-bounds");
 // Simplest first cut: static partitioning.
 int index = work_id;
 for (int j = 0; j < subclasses_of_ref; j++, index += _n_queues) {
 _ref_processor.enqueue_discovered_reflist(
 }
 }
 };
 // Enqueue references that are not made active again
-void ReferenceProcessor::enqueue_discovered_reflists(oop* pending_list_addr,
+void ReferenceProcessor::enqueue_discovered_reflists(HeapWord* pending_list_addr,
 AbstractRefProcTaskExecutor* task_executor) {
 if (_processing_is_mt && task_executor != NULL) {
 // Parallel code
 RefProcEnqueueTask tsk(*this, _discoveredSoftRefs,
-pending_list_addr, _sentinelRef, _num_q);
+pending_list_addr, sentinel_ref(), _num_q);
 task_executor->execute(tsk);
 } else {
 // Serial code: call the parent class's implementation
 for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
 enqueue_discovered_reflist(_discoveredSoftRefs[i], pending_list_addr);
-_discoveredSoftRefs[i].set_head(_sentinelRef);
+_discoveredSoftRefs[i].set_head(sentinel_ref());
 _discoveredSoftRefs[i].set_length(0);
 }
 }
 }
 inline DiscoveredListIterator(DiscoveredList&    refs_list,
 OopClosure*        keep_alive,
 BoolObjectClosure* is_alive);
 // End Of List.
-inline bool has_next() const
+inline bool has_next() const { return _next != ReferenceProcessor::sentinel_ref(); }
-{ return _next != ReferenceProcessor::_sentinelRef; }
 // Get oop to the Reference object.
-inline oop  obj() const { return _ref; }
+inline oop obj() const { return _ref; }
 // Get oop to the referent object.
-inline oop  referent() const { return _referent; }
+inline oop referent() const { return _referent; }
 // Returns true if referent is alive.
 inline bool is_referent_alive() const;
 // Loads data for the current reference.
 // Make the Reference object active again.
 inline void make_active() { java_lang_ref_Reference::set_next(_ref, NULL); }
 // Make the referent alive.
-inline void make_referent_alive() { _keep_alive->do_oop(_referent_addr); }
+inline void make_referent_alive() {
+if (UseCompressedOops) {
+_keep_alive->do_oop((narrowOop*)_referent_addr);
+} else {
+_keep_alive->do_oop((oop*)_referent_addr);
+}
+}
 // Update the discovered field.
-inline void update_discovered() { _keep_alive->do_oop(_prev_next); }
+inline void update_discovered() {
+// First _prev_next ref actually points into DiscoveredList (gross).
+if (UseCompressedOops) {
+_keep_alive->do_oop((narrowOop*)_prev_next);
+} else {
+_keep_alive->do_oop((oop*)_prev_next);
+}
+}
 // NULL out referent pointer.
-inline void clear_referent() { *_referent_addr = NULL; }
+inline void clear_referent() { oop_store_raw(_referent_addr, NULL); }
 // Statistics
 NOT_PRODUCT(
 inline size_t processed() const { return _processed; }
 inline size_t removed() const   { return _removed; }
 private:
 inline void move_to_next();
 private:
 DiscoveredList&    _refs_list;
-oop*               _prev_next;
+HeapWord*          _prev_next;
 oop                _ref;
-oop*               _discovered_addr;
+HeapWord*          _discovered_addr;
 oop                _next;
-oop*               _referent_addr;
+HeapWord*          _referent_addr;
 oop                _referent;
 OopClosure*        _keep_alive;
 BoolObjectClosure* _is_alive;
 DEBUG_ONLY(
 oop                _first_seen; // cyclic linked list check
 inline DiscoveredListIterator::DiscoveredListIterator(DiscoveredList&    refs_list,
 OopClosure*        keep_alive,
 BoolObjectClosure* is_alive)
 : _refs_list(refs_list),
-_prev_next(refs_list.head_ptr()),
+_prev_next(refs_list.adr_head()),
 _ref(refs_list.head()),
 #ifdef ASSERT
 _first_seen(refs_list.head()),
 #endif
 #ifndef PRODUCT
 _next(refs_list.head()),
 _keep_alive(keep_alive),
 _is_alive(is_alive)
 { }
-inline bool DiscoveredListIterator::is_referent_alive() const
+inline bool DiscoveredListIterator::is_referent_alive() const {
-{
 return _is_alive->do_object_b(_referent);
 }
-inline void DiscoveredListIterator::load_ptrs(DEBUG_ONLY(bool allow_null_referent))
+inline void DiscoveredListIterator::load_ptrs(DEBUG_ONLY(bool allow_null_referent)) {
-{
 _discovered_addr = java_lang_ref_Reference::discovered_addr(_ref);
-assert(_discovered_addr && (*_discovered_addr)->is_oop_or_null(),
+oop discovered = java_lang_ref_Reference::discovered(_ref);
+assert(_discovered_addr && discovered->is_oop_or_null(),
 "discovered field is bad");
-_next = *_discovered_addr;
+_next = discovered;
 _referent_addr = java_lang_ref_Reference::referent_addr(_ref);
-_referent = *_referent_addr;
+_referent = java_lang_ref_Reference::referent(_ref);
 assert(Universe::heap()->is_in_reserved_or_null(_referent),
 "Wrong oop found in java.lang.Reference object");
 assert(allow_null_referent ?
 _referent->is_oop_or_null()
 : _referent->is_oop(),
 "bad referent");
 }
-inline void DiscoveredListIterator::next()
+inline void DiscoveredListIterator::next() {
-{
 _prev_next = _discovered_addr;
 move_to_next();
 }
-inline void DiscoveredListIterator::remove()
+inline void DiscoveredListIterator::remove() {
-{
 assert(_ref->is_oop(), "Dropping a bad reference");
-// Clear the discovered_addr field so that the object does
+oop_store_raw(_discovered_addr, NULL);
-// not look like it has been discovered.
+// First _prev_next ref actually points into DiscoveredList (gross).
-*_discovered_addr = NULL;
+if (UseCompressedOops) {
 // Remove Reference object from list.
-*_prev_next = _next;
+oopDesc::encode_store_heap_oop_not_null((narrowOop*)_prev_next, _next);
+} else {
+// Remove Reference object from list.
+oopDesc::store_heap_oop((oop*)_prev_next, _next);
+}
 NOT_PRODUCT(_removed++);
 move_to_next();
 }
-inline void DiscoveredListIterator::move_to_next()
+inline void DiscoveredListIterator::move_to_next() {
-{
 _ref = _next;
 assert(_ref != _first_seen, "cyclic ref_list found");
 NOT_PRODUCT(_processed++);
 }
 // NOTE: process_phase*() are largely similar, and at a high level
 // merely iterate over the extant list applying a predicate to
 // each of its elements and possibly removing that element from the
 // list and applying some further closures to that element.
 // (SoftReferences only) Traverse the list and remove any SoftReferences whose
 // referents are not alive, but that should be kept alive for policy reasons.
 // Keep alive the transitive closure of all such referents.
 void
-ReferenceProcessor::process_phase1(DiscoveredList&    refs_list_addr,
+ReferenceProcessor::process_phase1(DiscoveredList&    refs_list,
 ReferencePolicy*   policy,
 BoolObjectClosure* is_alive,
 OopClosure*        keep_alive,
 VoidClosure*       complete_gc) {
 assert(policy != NULL, "Must have a non-NULL policy");
-DiscoveredListIterator iter(refs_list_addr, keep_alive, is_alive);
+DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
 // Decide which softly reachable refs should be kept alive.
 while (iter.has_next()) {
 iter.load_ptrs(DEBUG_ONLY(!discovery_is_atomic() /* allow_null_referent */));
 bool referent_is_dead = (iter.referent() != NULL) && !iter.is_referent_alive();
 if (referent_is_dead && !policy->should_clear_reference(iter.obj())) {
 if (TraceReferenceGC) {
 gclog_or_tty->print_cr("Dropping reference (" INTPTR_FORMAT ": %s"  ") by policy",
-(address)iter.obj(), iter.obj()->blueprint()->internal_name());
+iter.obj(), iter.obj()->blueprint()->internal_name());
 }
 // Make the Reference object active again
 iter.make_active();
 // keep the referent around
 iter.make_referent_alive();
 }
 // Traverse the list and remove any Refs that are not active, or
 // whose referents are either alive or NULL.
 void
-ReferenceProcessor::pp2_work(DiscoveredList&    refs_list_addr,
+ReferenceProcessor::pp2_work(DiscoveredList&    refs_list,
 BoolObjectClosure* is_alive,
-OopClosure*        keep_alive)
+OopClosure*        keep_alive) {
-{
 assert(discovery_is_atomic(), "Error");
-DiscoveredListIterator iter(refs_list_addr, keep_alive, is_alive);
+DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
 while (iter.has_next()) {
 iter.load_ptrs(DEBUG_ONLY(false /* allow_null_referent */));
-DEBUG_ONLY(oop* next_addr = java_lang_ref_Reference::next_addr(iter.obj());)
+DEBUG_ONLY(oop next = java_lang_ref_Reference::next(iter.obj());)
-assert(*next_addr == NULL, "Should not discover inactive Reference");
+assert(next == NULL, "Should not discover inactive Reference");
 if (iter.is_referent_alive()) {
 if (TraceReferenceGC) {
 gclog_or_tty->print_cr("Dropping strongly reachable reference (" INTPTR_FORMAT ": %s)",
-(address)iter.obj(), iter.obj()->blueprint()->internal_name());
+iter.obj(), iter.obj()->blueprint()->internal_name());
 }
 // The referent is reachable after all.
 // Update the referent pointer as necessary: Note that this
 // should not entail any recursive marking because the
 // referent must already have been traversed.
 }
 )
 }
 void
-ReferenceProcessor::pp2_work_concurrent_discovery(
+ReferenceProcessor::pp2_work_concurrent_discovery(DiscoveredList&    refs_list,
-DiscoveredList&    refs_list_addr,
+BoolObjectClosure* is_alive,
-BoolObjectClosure* is_alive,
+OopClosure*        keep_alive,
-OopClosure*        keep_alive,
+VoidClosure*       complete_gc) {
-VoidClosure*       complete_gc)
-{
 assert(!discovery_is_atomic(), "Error");
-DiscoveredListIterator iter(refs_list_addr, keep_alive, is_alive);
+DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
 while (iter.has_next()) {
 iter.load_ptrs(DEBUG_ONLY(true /* allow_null_referent */));
-oop* next_addr = java_lang_ref_Reference::next_addr(iter.obj());
+HeapWord* next_addr = java_lang_ref_Reference::next_addr(iter.obj());
+oop next = java_lang_ref_Reference::next(iter.obj());
 if ((iter.referent() == NULL || iter.is_referent_alive() ||
-*next_addr != NULL)) {
+next != NULL)) {
-assert((*next_addr)->is_oop_or_null(), "bad next field");
+assert(next->is_oop_or_null(), "bad next field");
 // Remove Reference object from list
 iter.remove();
 // Trace the cohorts
 iter.make_referent_alive();
-keep_alive->do_oop(next_addr);
+if (UseCompressedOops) {
+keep_alive->do_oop((narrowOop*)next_addr);
+} else {
+keep_alive->do_oop((oop*)next_addr);
+}
 } else {
 iter.next();
 }
 }
 // Now close the newly reachable set
 }
 )
 }
 // Traverse the list and process the referents, by either
-// either clearing them or keeping them (and their reachable
+// clearing them or keeping them (and their reachable
 // closure) alive.
 void
-ReferenceProcessor::process_phase3(DiscoveredList&    refs_list_addr,
+ReferenceProcessor::process_phase3(DiscoveredList&    refs_list,
 bool               clear_referent,
 BoolObjectClosure* is_alive,
 OopClosure*        keep_alive,
 VoidClosure*       complete_gc) {
-DiscoveredListIterator iter(refs_list_addr, keep_alive, is_alive);
+DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
 while (iter.has_next()) {
 iter.update_discovered();
 iter.load_ptrs(DEBUG_ONLY(false /* allow_null_referent */));
 if (clear_referent) {
 // NULL out referent pointer
 iter.make_referent_alive();
 }
 if (TraceReferenceGC) {
 gclog_or_tty->print_cr("Adding %sreference (" INTPTR_FORMAT ": %s) as pending",
 clear_referent ? "cleared " : "",
-(address)iter.obj(), iter.obj()->blueprint()->internal_name());
+iter.obj(), iter.obj()->blueprint()->internal_name());
 }
 assert(iter.obj()->is_oop(UseConcMarkSweepGC), "Adding a bad reference");
 // If discovery is concurrent, we may have objects with null referents,
 // being those that were concurrently cleared after they were discovered
 // (and not subsequently precleaned).
 // Close the reachable set
 complete_gc->do_void();
 }
 void
-ReferenceProcessor::abandon_partial_discovered_list(DiscoveredList& ref_list) {
+ReferenceProcessor::abandon_partial_discovered_list(DiscoveredList& refs_list) {
-oop obj = ref_list.head();
+oop obj = refs_list.head();
-while (obj != _sentinelRef) {
+while (obj != sentinel_ref()) {
-oop* discovered_addr = java_lang_ref_Reference::discovered_addr(obj);
+oop discovered = java_lang_ref_Reference::discovered(obj);
-obj = *discovered_addr;
+java_lang_ref_Reference::set_discovered_raw(obj, NULL);
-*discovered_addr = NULL;
+obj = discovered;
 }
-ref_list.set_head(_sentinelRef);
+refs_list.set_head(sentinel_ref());
-ref_list.set_length(0);
+refs_list.set_length(0);
 }
 void
 ReferenceProcessor::abandon_partial_discovered_list_arr(DiscoveredList refs_lists[]) {
 for (int i = 0; i < _num_q; i++) {
 oop move_tail = move_head;
 oop new_head  = move_head;
 // find an element to split the list on
 for (size_t j = 0; j < refs_to_move; ++j) {
 move_tail = new_head;
-new_head = *java_lang_ref_Reference::discovered_addr(new_head);
+new_head = java_lang_ref_Reference::discovered(new_head);
 }
 java_lang_ref_Reference::set_discovered(move_tail, ref_lists[to_idx].head());
 ref_lists[to_idx].set_head(move_head);
 ref_lists[to_idx].set_length(ref_lists[to_idx].length() + refs_to_move);
 ref_lists[from_idx].set_head(new_head);
 assert(!discovery_is_atomic(), "Else why call this method?");
 DiscoveredListIterator iter(refs_list, NULL, NULL);
 size_t length = refs_list.length();
 while (iter.has_next()) {
 iter.load_ptrs(DEBUG_ONLY(true /* allow_null_referent */));
-oop* next_addr = java_lang_ref_Reference::next_addr(iter.obj());
+oop next = java_lang_ref_Reference::next(iter.obj());
-assert((*next_addr)->is_oop_or_null(), "bad next field");
+assert(next->is_oop_or_null(), "bad next field");
 // If referent has been cleared or Reference is not active,
 // drop it.
-if (iter.referent() == NULL || *next_addr != NULL) {
+if (iter.referent() == NULL || next != NULL) {
 debug_only(
 if (PrintGCDetails && TraceReferenceGC) {
 gclog_or_tty->print_cr("clean_up_discovered_list: Dropping Reference: "
 INTPTR_FORMAT " with next field: " INTPTR_FORMAT
 " and referent: " INTPTR_FORMAT,
-(address)iter.obj(), (address)*next_addr, (address)iter.referent());
+iter.obj(), next, iter.referent());
 }
 )
 // Remove Reference object from list
 iter.remove();
 --length;
 ShouldNotReachHere();
 }
 return list;
 }
-inline void ReferenceProcessor::add_to_discovered_list_mt(DiscoveredList& list,
+inline void
-oop obj, oop* discovered_addr) {
+ReferenceProcessor::add_to_discovered_list_mt(DiscoveredList& refs_list,
+oop             obj,
+HeapWord*       discovered_addr) {
 assert(_discovery_is_mt, "!_discovery_is_mt should have been handled by caller");
 // First we must make sure this object is only enqueued once. CAS in a non null
 // discovered_addr.
-oop retest = (oop)Atomic::cmpxchg_ptr(list.head(), discovered_addr, NULL);
+oop retest = oopDesc::atomic_compare_exchange_oop(refs_list.head(), discovered_addr,
+NULL);
 if (retest == NULL) {
 // This thread just won the right to enqueue the object.
 // We have separate lists for enqueueing so no synchronization
 // is necessary.
-list.set_head(obj);
+refs_list.set_head(obj);
-list.set_length(list.length() + 1);
+refs_list.set_length(refs_list.length() + 1);
 } else {
 // If retest was non NULL, another thread beat us to it:
 // The reference has already been discovered...
 if (TraceReferenceGC) {
 gclog_or_tty->print_cr("Already enqueued reference (" INTPTR_FORMAT ": %s)",
 obj, obj->blueprint()->internal_name());
 }
 }
 }
 // We mention two of several possible choices here:
 // #0: if the reference object is not in the "originating generation"
 //     (or part of the heap being collected, indicated by our "span"
 //     we don't treat it specially (i.e. we scan it as we would
 // (rather than processing discovered refs).
 if (!_discovering_refs || !RegisterReferences) {
 return false;
 }
 // We only enqueue active references.
-oop* next_addr = java_lang_ref_Reference::next_addr(obj);
+oop next = java_lang_ref_Reference::next(obj);
-if (*next_addr != NULL) {
+if (next != NULL) {
 return false;
 }
 HeapWord* obj_addr = (HeapWord*)obj;
 if (RefDiscoveryPolicy == ReferenceBasedDiscovery &&
 if (is_alive_non_header()->do_object_b(referent)) {
 return false;  // referent is reachable
 }
 }
-oop* discovered_addr = java_lang_ref_Reference::discovered_addr(obj);
+HeapWord* discovered_addr = java_lang_ref_Reference::discovered_addr(obj);
-assert(discovered_addr != NULL && (*discovered_addr)->is_oop_or_null(),
+oop  discovered = java_lang_ref_Reference::discovered(obj);
-"bad discovered field");
+assert(discovered->is_oop_or_null(), "bad discovered field");
-if (*discovered_addr != NULL) {
+if (discovered != NULL) {
 // The reference has already been discovered...
 if (TraceReferenceGC) {
 gclog_or_tty->print_cr("Already enqueued reference (" INTPTR_FORMAT ": %s)",
-(oopDesc*)obj, obj->blueprint()->internal_name());
+obj, obj->blueprint()->internal_name());
 }
 if (RefDiscoveryPolicy == ReferentBasedDiscovery) {
 // assumes that an object is not processed twice;
 // if it's been already discovered it must be on another
 // generation's discovered list; so we won't discover it.
 // We do a raw store here, the field will be visited later when
 // processing the discovered references.
 if (_discovery_is_mt) {
 add_to_discovered_list_mt(*list, obj, discovered_addr);
 } else {
-*discovered_addr = list->head();
+oop_store_raw(discovered_addr, list->head());
 list->set_head(obj);
 list->set_length(list->length() + 1);
 }
 // In the MT discovery case, it is currently possible to see
 // only used for debugging support.
 if (TraceReferenceGC) {
 oop referent = java_lang_ref_Reference::referent(obj);
 if (PrintGCDetails) {
 gclog_or_tty->print_cr("Enqueued reference (" INTPTR_FORMAT ": %s)",
-(oopDesc*) obj, obj->blueprint()->internal_name());
+obj, obj->blueprint()->internal_name());
 }
 assert(referent->is_oop(), "Enqueued a bad referent");
 }
 assert(obj->is_oop(), "Enqueued a bad reference");
 return true;
 // Walk the given discovered ref list, and remove all reference objects
 // whose referents are still alive, whose referents are NULL or which
 // are not active (have a non-NULL next field). NOTE: For this to work
 // correctly, refs discovery can not be happening concurrently with this
 // step.
-void ReferenceProcessor::preclean_discovered_reflist(
+void
-DiscoveredList& refs_list, BoolObjectClosure* is_alive,
+ReferenceProcessor::preclean_discovered_reflist(DiscoveredList&    refs_list,
-OopClosure* keep_alive, VoidClosure* complete_gc, YieldClosure* yield) {
+BoolObjectClosure* is_alive,
+OopClosure*        keep_alive,
+VoidClosure*       complete_gc,
+YieldClosure*      yield) {
 DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
 size_t length = refs_list.length();
 while (iter.has_next()) {
 iter.load_ptrs(DEBUG_ONLY(true /* allow_null_referent */));
-oop* next_addr = java_lang_ref_Reference::next_addr(iter.obj());
+oop obj = iter.obj();
+oop next = java_lang_ref_Reference::next(obj);
 if (iter.referent() == NULL || iter.is_referent_alive() ||
-*next_addr != NULL) {
+next != NULL) {
 // The referent has been cleared, or is alive, or the Reference is not
 // active; we need to trace and mark its cohort.
 if (TraceReferenceGC) {
 gclog_or_tty->print_cr("Precleaning Reference (" INTPTR_FORMAT ": %s)",
 iter.obj(), iter.obj()->blueprint()->internal_name());
 // Remove Reference object from list
 iter.remove();
 --length;
 // Keep alive its cohort.
 iter.make_referent_alive();
-keep_alive->do_oop(next_addr);
+if (UseCompressedOops) {
+narrowOop* next_addr = (narrowOop*)java_lang_ref_Reference::next_addr(obj);
+keep_alive->do_oop(next_addr);
+} else {
+oop* next_addr = (oop*)java_lang_ref_Reference::next_addr(obj);
+keep_alive->do_oop(next_addr);
+}
 } else {
 iter.next();
 }
 }
 refs_list.set_length(length);
 // empty for now
 }
 #endif
 void ReferenceProcessor::verify() {
-guarantee(_sentinelRef != NULL && _sentinelRef->is_oop(), "Lost _sentinelRef");
+guarantee(sentinel_ref() != NULL && sentinel_ref()->is_oop(), "Lost _sentinelRef");
 }
 #ifndef PRODUCT
 void ReferenceProcessor::clear_discovered_references() {
 guarantee(!_discovering_refs, "Discovering refs?");
 for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
 oop obj = _discoveredSoftRefs[i].head();
-while (obj != _sentinelRef) {
+while (obj != sentinel_ref()) {
 oop next = java_lang_ref_Reference::discovered(obj);
 java_lang_ref_Reference::set_discovered(obj, (oop) NULL);
 obj = next;
 }
-_discoveredSoftRefs[i].set_head(_sentinelRef);
+_discoveredSoftRefs[i].set_head(sentinel_ref());
 _discoveredSoftRefs[i].set_length(0);
 }
 }
 #endif // PRODUCT

changeset 360	21d113ecbf6a
parent 178	3f20890fb323
child 670	ddf3e9583f2f
child 1374	4c24294029a9