/*

 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "classfile/javaClasses.hpp"

#include "classfile/systemDictionary.hpp"

#include "gc_implementation/shared/markSweep.inline.hpp"

#include "gc_interface/collectedHeap.hpp"

#include "gc_interface/collectedHeap.inline.hpp"

#include "memory/genCollectedHeap.hpp"

#include "memory/genOopClosures.inline.hpp"

#include "oops/instanceRefKlass.hpp"

#include "oops/oop.inline.hpp"

#include "utilities/preserveException.hpp"

#ifndef SERIALGC

#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"

#include "gc_implementation/g1/g1OopClosures.inline.hpp"

#include "gc_implementation/g1/g1RemSet.inline.hpp"

#include "gc_implementation/g1/heapRegionSeq.inline.hpp"

#include "gc_implementation/parNew/parOopClosures.inline.hpp"

#include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"

#include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"

#include "oops/oop.pcgc.inline.hpp"

#endif

template <class T>

static void specialized_oop_follow_contents(instanceRefKlass* ref, oop obj) {

  T* referent_addr = (T*)java_lang_ref_Reference::referent_addr(obj);

  T heap_oop = oopDesc::load_heap_oop(referent_addr);

  debug_only(

    if(TraceReferenceGC && PrintGCDetails) {

      gclog_or_tty->print_cr("instanceRefKlass::oop_follow_contents " INTPTR_FORMAT, obj);

    }

  )

  if (!oopDesc::is_null(heap_oop)) {

    oop referent = oopDesc::decode_heap_oop_not_null(heap_oop);

    if (!referent->is_gc_marked() &&

        MarkSweep::ref_processor()->

          discover_reference(obj, ref->reference_type())) {

      // reference already enqueued, referent will be traversed later

      ref->instanceKlass::oop_follow_contents(obj);

      debug_only(

        if(TraceReferenceGC && PrintGCDetails) {

          gclog_or_tty->print_cr("       Non NULL enqueued " INTPTR_FORMAT, obj);

        }

      )

      return;

    } else {

      // treat referent as normal oop

      debug_only(

        if(TraceReferenceGC && PrintGCDetails) {

          gclog_or_tty->print_cr("       Non NULL normal " INTPTR_FORMAT, obj);

        }

      )

      MarkSweep::mark_and_push(referent_addr);

    }

  }

  // treat next as normal oop.  next is a link in the pending list.

  T* next_addr = (T*)java_lang_ref_Reference::next_addr(obj);

  debug_only(

    if(TraceReferenceGC && PrintGCDetails) {

      gclog_or_tty->print_cr("   Process next as normal " INTPTR_FORMAT, next_addr);

    }

  )

  MarkSweep::mark_and_push(next_addr);

  ref->instanceKlass::oop_follow_contents(obj);

}

void instanceRefKlass::oop_follow_contents(oop obj) {

  if (UseCompressedOops) {

    specialized_oop_follow_contents<narrowOop>(this, obj);

  } else {

    specialized_oop_follow_contents<oop>(this, obj);

  }

}

#ifndef SERIALGC

template <class T>

void specialized_oop_follow_contents(instanceRefKlass* ref,

                                     ParCompactionManager* cm,

                                     oop obj) {

  T* referent_addr = (T*)java_lang_ref_Reference::referent_addr(obj);

  T heap_oop = oopDesc::load_heap_oop(referent_addr);

  debug_only(

    if(TraceReferenceGC && PrintGCDetails) {

      gclog_or_tty->print_cr("instanceRefKlass::oop_follow_contents " INTPTR_FORMAT, obj);

    }

  )

  if (!oopDesc::is_null(heap_oop)) {

    oop referent = oopDesc::decode_heap_oop_not_null(heap_oop);

    if (PSParallelCompact::mark_bitmap()->is_unmarked(referent) &&

        PSParallelCompact::ref_processor()->

          discover_reference(obj, ref->reference_type())) {

      // reference already enqueued, referent will be traversed later

      ref->instanceKlass::oop_follow_contents(cm, obj);

      debug_only(

        if(TraceReferenceGC && PrintGCDetails) {

          gclog_or_tty->print_cr("       Non NULL enqueued " INTPTR_FORMAT, obj);

        }

      )

      return;

    } else {

      // treat referent as normal oop

      debug_only(

        if(TraceReferenceGC && PrintGCDetails) {

          gclog_or_tty->print_cr("       Non NULL normal " INTPTR_FORMAT, obj);

        }

      )

      PSParallelCompact::mark_and_push(cm, referent_addr);

    }

  }

  // treat next as normal oop.  next is a link in the pending list.

  T* next_addr = (T*)java_lang_ref_Reference::next_addr(obj);

  debug_only(

    if(TraceReferenceGC && PrintGCDetails) {

      gclog_or_tty->print_cr("   Process next as normal " INTPTR_FORMAT, next_addr);

    }

  )

  PSParallelCompact::mark_and_push(cm, next_addr);

  ref->instanceKlass::oop_follow_contents(cm, obj);

}

void instanceRefKlass::oop_follow_contents(ParCompactionManager* cm,

                                           oop obj) {

  if (UseCompressedOops) {

    specialized_oop_follow_contents<narrowOop>(this, cm, obj);

  } else {

    specialized_oop_follow_contents<oop>(this, cm, obj);

  }

}

#endif // SERIALGC

#ifdef ASSERT

template <class T> void trace_reference_gc(const char *s, oop obj,

                                           T* referent_addr,

                                           T* next_addr,

                                           T* discovered_addr) {

  if(TraceReferenceGC && PrintGCDetails) {

    gclog_or_tty->print_cr("%s obj " INTPTR_FORMAT, s, (address)obj);

    gclog_or_tty->print_cr("     referent_addr/* " INTPTR_FORMAT " / "

         INTPTR_FORMAT, referent_addr,

         referent_addr ?

           (address)oopDesc::load_decode_heap_oop(referent_addr) : NULL);

    gclog_or_tty->print_cr("     next_addr/* " INTPTR_FORMAT " / "

         INTPTR_FORMAT, next_addr,

         next_addr ? (address)oopDesc::load_decode_heap_oop(next_addr) : NULL);

    gclog_or_tty->print_cr("     discovered_addr/* " INTPTR_FORMAT " / "

         INTPTR_FORMAT, discovered_addr,

         discovered_addr ?

           (address)oopDesc::load_decode_heap_oop(discovered_addr) : NULL);

  }

}

#endif

template <class T> void specialized_oop_adjust_pointers(instanceRefKlass *ref, oop obj) {

  T* referent_addr = (T*)java_lang_ref_Reference::referent_addr(obj);

  MarkSweep::adjust_pointer(referent_addr);

  T* next_addr = (T*)java_lang_ref_Reference::next_addr(obj);

  MarkSweep::adjust_pointer(next_addr);

  T* discovered_addr = (T*)java_lang_ref_Reference::discovered_addr(obj);

  MarkSweep::adjust_pointer(discovered_addr);

  debug_only(trace_reference_gc("instanceRefKlass::oop_adjust_pointers", obj,

                                referent_addr, next_addr, discovered_addr);)

}

int instanceRefKlass::oop_adjust_pointers(oop obj) {

  int size = size_helper();

  instanceKlass::oop_adjust_pointers(obj);

  if (UseCompressedOops) {

    specialized_oop_adjust_pointers<narrowOop>(this, obj);

  } else {

    specialized_oop_adjust_pointers<oop>(this, obj);

  }

  return size;

}

#define InstanceRefKlass_SPECIALIZED_OOP_ITERATE(T, nv_suffix, contains)        \

  if (closure->apply_to_weak_ref_discovered_field()) {                          \

    T* disc_addr = (T*)java_lang_ref_Reference::discovered_addr(obj);           \

    closure->do_oop##nv_suffix(disc_addr);                                      \

  }                                                                             \

                                                                                \

  T* referent_addr = (T*)java_lang_ref_Reference::referent_addr(obj);           \

  T heap_oop = oopDesc::load_heap_oop(referent_addr);                           \

  if (!oopDesc::is_null(heap_oop) && contains(referent_addr)) {                 \

    ReferenceProcessor* rp = closure->_ref_processor;                           \

    oop referent = oopDesc::decode_heap_oop_not_null(heap_oop);                 \

    if (!referent->is_gc_marked() && (rp != NULL) &&                            \

        rp->discover_reference(obj, reference_type())) {                        \

      return size;                                                              \

    } else {                                                                    \

      /* treat referent as normal oop */                                        \

      SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::irk);\

      closure->do_oop##nv_suffix(referent_addr);                                \

    }                                                                           \

  }                                                                             \

  /* treat next as normal oop */                                                \

  T* next_addr = (T*)java_lang_ref_Reference::next_addr(obj);                   \

  if (contains(next_addr)) {                                                    \

    SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::irk); \

    closure->do_oop##nv_suffix(next_addr);                                      \

  }                                                                             \

  return size;                                                                  \

template <class T> bool contains(T *t) { return true; }

// Macro to define instanceRefKlass::oop_oop_iterate for virtual/nonvirtual for

// all closures.  Macros calling macros above for each oop size.

#define InstanceRefKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix)        \

                                                                                \

int instanceRefKlass::                                                          \

oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) {                  \

  /* Get size before changing pointers */                                       \

  SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::irk);\

                                                                                \

  int size = instanceKlass::oop_oop_iterate##nv_suffix(obj, closure);           \

                                                                                \

  if (UseCompressedOops) {                                                      \

    InstanceRefKlass_SPECIALIZED_OOP_ITERATE(narrowOop, nv_suffix, contains);   \

  } else {                                                                      \

    InstanceRefKlass_SPECIALIZED_OOP_ITERATE(oop, nv_suffix, contains);         \

  }                                                                             \

}

#ifndef SERIALGC

#define InstanceRefKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \

                                                                                \

int instanceRefKlass::                                                          \

oop_oop_iterate_backwards##nv_suffix(oop obj, OopClosureType* closure) {        \

  /* Get size before changing pointers */                                       \

  SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::irk);\

                                                                                \

  int size = instanceKlass::oop_oop_iterate_backwards##nv_suffix(obj, closure); \

                                                                                \

  if (UseCompressedOops) {                                                      \

    InstanceRefKlass_SPECIALIZED_OOP_ITERATE(narrowOop, nv_suffix, contains);   \

  } else {                                                                      \

    InstanceRefKlass_SPECIALIZED_OOP_ITERATE(oop, nv_suffix, contains);         \

  }                                                                             \

}

#endif // !SERIALGC

#define InstanceRefKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix)      \

                                                                                \

int instanceRefKlass::                                                          \

oop_oop_iterate##nv_suffix##_m(oop obj,                                         \

                               OopClosureType* closure,                         \

                               MemRegion mr) {                                  \

  SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::irk);\

                                                                                \

  int size = instanceKlass::oop_oop_iterate##nv_suffix##_m(obj, closure, mr);   \

  if (UseCompressedOops) {                                                      \

    InstanceRefKlass_SPECIALIZED_OOP_ITERATE(narrowOop, nv_suffix, mr.contains); \

  } else {                                                                      \

    InstanceRefKlass_SPECIALIZED_OOP_ITERATE(oop, nv_suffix, mr.contains);      \

  }                                                                             \

}

ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceRefKlass_OOP_OOP_ITERATE_DEFN)

ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceRefKlass_OOP_OOP_ITERATE_DEFN)

#ifndef SERIALGC

ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceRefKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)

ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceRefKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)

#endif // SERIALGC

ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceRefKlass_OOP_OOP_ITERATE_DEFN_m)

ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceRefKlass_OOP_OOP_ITERATE_DEFN_m)

#ifndef SERIALGC

template <class T>

void specialized_oop_push_contents(instanceRefKlass *ref,

                                   PSPromotionManager* pm, oop obj) {

  T* referent_addr = (T*)java_lang_ref_Reference::referent_addr(obj);

  if (PSScavenge::should_scavenge(referent_addr)) {

    ReferenceProcessor* rp = PSScavenge::reference_processor();

    if (rp->discover_reference(obj, ref->reference_type())) {

      // reference already enqueued, referent and next will be traversed later

      ref->instanceKlass::oop_push_contents(pm, obj);

      return;

    } else {

      // treat referent as normal oop

      pm->claim_or_forward_depth(referent_addr);

    }

  }

  // treat next as normal oop

  T* next_addr = (T*)java_lang_ref_Reference::next_addr(obj);

  if (PSScavenge::should_scavenge(next_addr)) {

    pm->claim_or_forward_depth(next_addr);

  }

  ref->instanceKlass::oop_push_contents(pm, obj);

}

void instanceRefKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {

  if (UseCompressedOops) {

    specialized_oop_push_contents<narrowOop>(this, pm, obj);

  } else {

    specialized_oop_push_contents<oop>(this, pm, obj);

  }

}

template <class T>

void specialized_oop_update_pointers(instanceRefKlass *ref,

                                    ParCompactionManager* cm, oop obj) {

  T* referent_addr = (T*)java_lang_ref_Reference::referent_addr(obj);

  PSParallelCompact::adjust_pointer(referent_addr);

  T* next_addr = (T*)java_lang_ref_Reference::next_addr(obj);

  PSParallelCompact::adjust_pointer(next_addr);

  T* discovered_addr = (T*)java_lang_ref_Reference::discovered_addr(obj);

  PSParallelCompact::adjust_pointer(discovered_addr);

  debug_only(trace_reference_gc("instanceRefKlass::oop_update_ptrs", obj,

                                referent_addr, next_addr, discovered_addr);)

}

int instanceRefKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {

  instanceKlass::oop_update_pointers(cm, obj);

  if (UseCompressedOops) {

    specialized_oop_update_pointers<narrowOop>(this, cm, obj);

  } else {

    specialized_oop_update_pointers<oop>(this, cm, obj);

  }

  return size_helper();

}

#endif // SERIALGC

void instanceRefKlass::update_nonstatic_oop_maps(klassOop k) {

  // Clear the nonstatic oop-map entries corresponding to referent

  // and nextPending field.  They are treated specially by the

  // garbage collector.

  // The discovered field is used only by the garbage collector

  // and is also treated specially.

  instanceKlass* ik = instanceKlass::cast(k);

  // Check that we have the right class

  debug_only(static bool first_time = true);

  assert(k == SystemDictionary::Reference_klass() && first_time,

         "Invalid update of maps");

  debug_only(first_time = false);

  assert(ik->nonstatic_oop_map_count() == 1, "just checking");

  OopMapBlock* map = ik->start_of_nonstatic_oop_maps();

  // Check that the current map is (2,4) - currently points at field with

  // offset 2 (words) and has 4 map entries.

  debug_only(int offset = java_lang_ref_Reference::referent_offset);

  debug_only(unsigned int count = ((java_lang_ref_Reference::discovered_offset -

    java_lang_ref_Reference::referent_offset)/heapOopSize) + 1);

  if (UseSharedSpaces) {

    assert(map->offset() == java_lang_ref_Reference::queue_offset &&

           map->count() == 1, "just checking");

  } else {

    assert(map->offset() == offset && map->count() == count,

           "just checking");

    // Update map to (3,1) - point to offset of 3 (words) with 1 map entry.

    map->set_offset(java_lang_ref_Reference::queue_offset);

    map->set_count(1);

  }

}

// Verification

void instanceRefKlass::oop_verify_on(oop obj, outputStream* st) {

  instanceKlass::oop_verify_on(obj, st);

  // Verify referent field

  oop referent = java_lang_ref_Reference::referent(obj);

  // We should make this general to all heaps

  GenCollectedHeap* gch = NULL;

  if (Universe::heap()->kind() == CollectedHeap::GenCollectedHeap)

    gch = GenCollectedHeap::heap();

  if (referent != NULL) {

    guarantee(referent->is_oop(), "referent field heap failed");

    if (gch != NULL && !gch->is_in_youngest(obj)) {

      // We do a specific remembered set check here since the referent

      // field is not part of the oop mask and therefore skipped by the

      // regular verify code.

      if (UseCompressedOops) {

        narrowOop* referent_addr = (narrowOop*)java_lang_ref_Reference::referent_addr(obj);

        obj->verify_old_oop(referent_addr, true);

      } else {

        oop* referent_addr = (oop*)java_lang_ref_Reference::referent_addr(obj);

        obj->verify_old_oop(referent_addr, true);

      }

    }

  }

  // Verify next field

  oop next = java_lang_ref_Reference::next(obj);

  if (next != NULL) {

    guarantee(next->is_oop(), "next field verify failed");

    guarantee(next->is_instanceRef(), "next field verify failed");

    if (gch != NULL && !gch->is_in_youngest(obj)) {

      // We do a specific remembered set check here since the next field is

      // not part of the oop mask and therefore skipped by the regular

      // verify code.

      if (UseCompressedOops) {

        narrowOop* next_addr = (narrowOop*)java_lang_ref_Reference::next_addr(obj);

        obj->verify_old_oop(next_addr, true);

      } else {

        oop* next_addr = (oop*)java_lang_ref_Reference::next_addr(obj);

        obj->verify_old_oop(next_addr, true);

      }

    }

  }

}

bool instanceRefKlass::owns_pending_list_lock(JavaThread* thread) {

  if (java_lang_ref_Reference::pending_list_lock() == NULL) return false;

  Handle h_lock(thread, java_lang_ref_Reference::pending_list_lock());

  return ObjectSynchronizer::current_thread_holds_lock(thread, h_lock);

}

void instanceRefKlass::acquire_pending_list_lock(BasicLock *pending_list_basic_lock) {

  // we may enter this with pending exception set

  PRESERVE_EXCEPTION_MARK;  // exceptions are never thrown, needed for TRAPS argument

  Handle h_lock(THREAD, java_lang_ref_Reference::pending_list_lock());

  ObjectSynchronizer::fast_enter(h_lock, pending_list_basic_lock, false, THREAD);

  assert(ObjectSynchronizer::current_thread_holds_lock(

           JavaThread::current(), h_lock),

         "Locking should have succeeded");

  if (HAS_PENDING_EXCEPTION) CLEAR_PENDING_EXCEPTION;

}

void instanceRefKlass::release_and_notify_pending_list_lock(

  BasicLock *pending_list_basic_lock) {

  // we may enter this with pending exception set

  PRESERVE_EXCEPTION_MARK;  // exceptions are never thrown, needed for TRAPS argument

  //

  Handle h_lock(THREAD, java_lang_ref_Reference::pending_list_lock());

  assert(ObjectSynchronizer::current_thread_holds_lock(

           JavaThread::current(), h_lock),

         "Lock should be held");

  // Notify waiters on pending lists lock if there is any reference.

  if (java_lang_ref_Reference::pending_list() != NULL) {

    ObjectSynchronizer::notifyall(h_lock, THREAD);

  }

  ObjectSynchronizer::fast_exit(h_lock(), pending_list_basic_lock, THREAD);

  if (HAS_PENDING_EXCEPTION) CLEAR_PENDING_EXCEPTION;

}