/*

 * Copyright (c) 2019, 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/classLoaderData.hpp"

#include "classfile/classLoaderDataGraph.hpp"

#include "gc/z/zAddress.hpp"

#include "gc/z/zHeap.inline.hpp"

#include "gc/z/zOop.hpp"

#include "gc/z/zResurrection.hpp"

#include "gc/z/zRootsIterator.hpp"

#include "gc/z/zStat.hpp"

#include "gc/z/zVerify.hpp"

#include "memory/allocation.hpp"

#include "memory/iterator.inline.hpp"

#include "oops/oop.inline.hpp"

#define BAD_OOP_REPORT(addr)                                                \

    "Bad oop " PTR_FORMAT " found at " PTR_FORMAT ", expected " PTR_FORMAT, \

    addr, p2i(p), ZAddress::good(addr)

class ZVerifyRootsClosure : public ZRootsIteratorClosure {

public:

  virtual void do_oop(oop* p) {

    uintptr_t value = ZOop::to_address(*p);

    if (value == 0) {

      return;

    }

    guarantee(!ZAddress::is_finalizable(value), BAD_OOP_REPORT(value));

    guarantee(ZAddress::is_good(value), BAD_OOP_REPORT(value));

    guarantee(oopDesc::is_oop(ZOop::from_address(value)), BAD_OOP_REPORT(value));

  }

  virtual void do_oop(narrowOop*) { ShouldNotReachHere(); }

};

template <bool VisitReferents>

class ZVerifyOopClosure : public ClaimMetadataVisitingOopIterateClosure, public ZRootsIteratorClosure  {

public:

  ZVerifyOopClosure() :

      ClaimMetadataVisitingOopIterateClosure(ClassLoaderData::_claim_other) {}

  virtual void do_oop(oop* p);

  virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }

  virtual ReferenceIterationMode reference_iteration_mode() {

    return VisitReferents ? DO_FIELDS : DO_FIELDS_EXCEPT_REFERENT;

  }

#ifdef ASSERT

  // Verification handled by the closure itself

  virtual bool should_verify_oops() {

    return false;

  }

#endif

};

class ZVerifyObjectClosure : public ObjectClosure {

private:

  bool _visit_referents;

public:

  ZVerifyObjectClosure(bool visit_referents) : _visit_referents(visit_referents) {}

  virtual void do_object(oop o);

};

template <typename RootsIterator>

void ZVerify::roots_impl() {

  if (ZVerifyRoots) {

    ZVerifyRootsClosure cl;

    RootsIterator iter;

    iter.oops_do(&cl);

  }

}

void ZVerify::roots_strong() {

  roots_impl<ZRootsIterator>();

}

class ZVerifyConcurrentRootsIterator : public ZConcurrentRootsIterator {

public:

  ZVerifyConcurrentRootsIterator()

      : ZConcurrentRootsIterator(ClassLoaderData::_claim_none) {}

};

void ZVerify::roots_concurrent() {

  roots_impl<ZVerifyConcurrentRootsIterator>();

}

void ZVerify::roots_weak() {

  assert(!ZResurrection::is_blocked(), "Invalid phase");

  roots_impl<ZWeakRootsIterator>();

}

void ZVerify::roots(bool verify_weaks) {

  roots_strong();

  roots_concurrent();

  if (verify_weaks) {

    roots_weak();

    roots_concurrent_weak();

  }

}

void ZVerify::objects(bool verify_weaks) {

  if (ZVerifyObjects) {

    ZVerifyObjectClosure cl(verify_weaks);

    ZHeap::heap()->object_iterate(&cl, verify_weaks);

  }

}

void ZVerify::roots_concurrent_weak() {

  assert(!ZResurrection::is_blocked(), "Invalid phase");

  roots_impl<ZConcurrentWeakRootsIterator>();

}

void ZVerify::roots_and_objects(bool verify_weaks) {

  ZStatTimerDisable  _disable;

  roots(verify_weaks);

  objects(verify_weaks);

}

void ZVerify::after_mark() {

  // Only verify strong roots and references.

  roots_and_objects(false /* verify_weaks */);

}

void ZVerify::after_weak_processing() {

  // Also verify weaks - all should have been processed at this point.

  roots_and_objects(true /* verify_weaks */);

}

template <bool VisitReferents>

void ZVerifyOopClosure<VisitReferents>::do_oop(oop* p) {

  guarantee(SafepointSynchronize::is_at_safepoint(), "Must be at a safepoint");

  guarantee(ZGlobalPhase == ZPhaseMarkCompleted, "Invalid phase");

  guarantee(!ZResurrection::is_blocked(), "Invalid phase");

  const oop o = RawAccess<>::oop_load(p);

  if (o == NULL) {

    return;

  }

  const uintptr_t addr = ZOop::to_address(o);

  if (VisitReferents) {

    guarantee(ZAddress::is_good(addr) || ZAddress::is_finalizable_good(addr), BAD_OOP_REPORT(addr));

  } else {

    // Should not encounter finalizable oops through strong-only paths. Assumes only strong roots are visited.

    guarantee(ZAddress::is_good(addr), BAD_OOP_REPORT(addr));

  }

  const uintptr_t good_addr = ZAddress::good(addr);

  guarantee(oopDesc::is_oop(ZOop::from_address(good_addr)), BAD_OOP_REPORT(addr));

}

void ZVerifyObjectClosure::do_object(oop o) {

  if (_visit_referents) {

    ZVerifyOopClosure<true /* VisitReferents */> cl;

    o->oop_iterate((OopIterateClosure*)&cl);

  } else {

    ZVerifyOopClosure<false /* VisitReferents */> cl;

    o->oop_iterate(&cl);

  }

}