/*

 * Copyright (c) 1997, 2017, 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/moduleEntry.hpp"

#include "classfile/packageEntry.hpp"

#include "classfile/symbolTable.hpp"

#include "classfile/systemDictionary.hpp"

#include "classfile/vmSymbols.hpp"

#include "gc/shared/collectedHeap.inline.hpp"

#include "gc/shared/specialized_oop_closures.hpp"

#include "memory/iterator.inline.hpp"

#include "memory/metadataFactory.hpp"

#include "memory/metaspaceClosure.hpp"

#include "memory/resourceArea.hpp"

#include "memory/universe.inline.hpp"

#include "oops/arrayKlass.inline.hpp"

#include "oops/instanceKlass.hpp"

#include "oops/klass.inline.hpp"

#include "oops/objArrayKlass.inline.hpp"

#include "oops/objArrayOop.inline.hpp"

#include "oops/oop.inline.hpp"

#include "oops/symbol.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/mutexLocker.hpp"

#include "utilities/macros.hpp"

ObjArrayKlass* ObjArrayKlass::allocate(ClassLoaderData* loader_data, int n, Klass* k, Symbol* name, TRAPS) {

  assert(ObjArrayKlass::header_size() <= InstanceKlass::header_size(),

      "array klasses must be same size as InstanceKlass");

  int size = ArrayKlass::static_size(ObjArrayKlass::header_size());

  return new (loader_data, size, THREAD) ObjArrayKlass(n, k, name);

}

Klass* ObjArrayKlass::allocate_objArray_klass(ClassLoaderData* loader_data,

                                                int n, Klass* element_klass, TRAPS) {

  // Eagerly allocate the direct array supertype.

  Klass* super_klass = NULL;

  if (!Universe::is_bootstrapping() || SystemDictionary::Object_klass_loaded()) {

    Klass* element_super = element_klass->super();

    if (element_super != NULL) {

      // The element type has a direct super.  E.g., String[] has direct super of Object[].

      super_klass = element_super->array_klass_or_null();

      bool supers_exist = super_klass != NULL;

      // Also, see if the element has secondary supertypes.

      // We need an array type for each.

      Array<Klass*>* element_supers = element_klass->secondary_supers();

      for( int i = element_supers->length()-1; i >= 0; i-- ) {

        Klass* elem_super = element_supers->at(i);

        if (elem_super->array_klass_or_null() == NULL) {

          supers_exist = false;

          break;

        }

      }

      if (!supers_exist) {

        // Oops.  Not allocated yet.  Back out, allocate it, and retry.

        Klass* ek = NULL;

        {

          MutexUnlocker mu(MultiArray_lock);

          MutexUnlocker mc(Compile_lock);   // for vtables

          super_klass = element_super->array_klass(CHECK_0);

          for( int i = element_supers->length()-1; i >= 0; i-- ) {

            Klass* elem_super = element_supers->at(i);

            elem_super->array_klass(CHECK_0);

          }

          // Now retry from the beginning

          ek = element_klass->array_klass(n, CHECK_0);

        }  // re-lock

        return ek;

      }

    } else {

      // The element type is already Object.  Object[] has direct super of Object.

      super_klass = SystemDictionary::Object_klass();

    }

  }

  // Create type name for klass.

  Symbol* name = NULL;

  if (!element_klass->is_instance_klass() ||

      (name = InstanceKlass::cast(element_klass)->array_name()) == NULL) {

    ResourceMark rm(THREAD);

    char *name_str = element_klass->name()->as_C_string();

    int len = element_klass->name()->utf8_length();

    char *new_str = NEW_RESOURCE_ARRAY(char, len + 4);

    int idx = 0;

    new_str[idx++] = '[';

    if (element_klass->is_instance_klass()) { // it could be an array or simple type

      new_str[idx++] = 'L';

    }

    memcpy(&new_str[idx], name_str, len * sizeof(char));

    idx += len;

    if (element_klass->is_instance_klass()) {

      new_str[idx++] = ';';

    }

    new_str[idx++] = '\0';

    name = SymbolTable::new_permanent_symbol(new_str, CHECK_0);

    if (element_klass->is_instance_klass()) {

      InstanceKlass* ik = InstanceKlass::cast(element_klass);

      ik->set_array_name(name);

    }

  }

  // Initialize instance variables

  ObjArrayKlass* oak = ObjArrayKlass::allocate(loader_data, n, element_klass, name, CHECK_0);

  // Add all classes to our internal class loader list here,

  // including classes in the bootstrap (NULL) class loader.

  // GC walks these as strong roots.

  loader_data->add_class(oak);

  ModuleEntry* module = oak->module();

  assert(module != NULL, "No module entry for array");

  // Call complete_create_array_klass after all instance variables has been initialized.

  ArrayKlass::complete_create_array_klass(oak, super_klass, module, CHECK_0);

  return oak;

}

ObjArrayKlass::ObjArrayKlass(int n, Klass* element_klass, Symbol* name) : ArrayKlass(name) {

  this->set_dimension(n);

  this->set_element_klass(element_klass);

  // decrement refcount because object arrays are not explicitly freed.  The

  // InstanceKlass array_name() keeps the name counted while the klass is

  // loaded.

  name->decrement_refcount();

  Klass* bk;

  if (element_klass->is_objArray_klass()) {

    bk = ObjArrayKlass::cast(element_klass)->bottom_klass();

  } else {

    bk = element_klass;

  }

  assert(bk != NULL && (bk->is_instance_klass() || bk->is_typeArray_klass()), "invalid bottom klass");

  this->set_bottom_klass(bk);

  this->set_class_loader_data(bk->class_loader_data());

  this->set_layout_helper(array_layout_helper(T_OBJECT));

  assert(this->is_array_klass(), "sanity");

  assert(this->is_objArray_klass(), "sanity");

}

int ObjArrayKlass::oop_size(oop obj) const {

  assert(obj->is_objArray(), "must be object array");

  return objArrayOop(obj)->object_size();

}

objArrayOop ObjArrayKlass::allocate(int length, TRAPS) {

  if (length >= 0) {

    if (length <= arrayOopDesc::max_array_length(T_OBJECT)) {

      int size = objArrayOopDesc::object_size(length);

      return (objArrayOop)CollectedHeap::array_allocate(this, size, length, THREAD);

    } else {

      report_java_out_of_memory("Requested array size exceeds VM limit");

      JvmtiExport::post_array_size_exhausted();

      THROW_OOP_0(Universe::out_of_memory_error_array_size());

    }

  } else {

    THROW_0(vmSymbols::java_lang_NegativeArraySizeException());

  }

}

static int multi_alloc_counter = 0;

oop ObjArrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) {

  int length = *sizes;

  // Call to lower_dimension uses this pointer, so most be called before a

  // possible GC

  Klass* ld_klass = lower_dimension();

  // If length < 0 allocate will throw an exception.

  objArrayOop array = allocate(length, CHECK_NULL);

  objArrayHandle h_array (THREAD, array);

  if (rank > 1) {

    if (length != 0) {

      for (int index = 0; index < length; index++) {

        ArrayKlass* ak = ArrayKlass::cast(ld_klass);

        oop sub_array = ak->multi_allocate(rank-1, &sizes[1], CHECK_NULL);

        h_array->obj_at_put(index, sub_array);

      }

    } else {

      // Since this array dimension has zero length, nothing will be

      // allocated, however the lower dimension values must be checked

      // for illegal values.

      for (int i = 0; i < rank - 1; ++i) {

        sizes += 1;

        if (*sizes < 0) {

          THROW_0(vmSymbols::java_lang_NegativeArraySizeException());

        }

      }

    }

  }

  return h_array();

}

// Either oop or narrowOop depending on UseCompressedOops.

template <class T> void ObjArrayKlass::do_copy(arrayOop s, T* src,

                               arrayOop d, T* dst, int length, TRAPS) {

  if (s == d) {

    // since source and destination are equal we do not need conversion checks.

    assert(length > 0, "sanity check");

  } else {

    // We have to make sure all elements conform to the destination array

    Klass* bound = ObjArrayKlass::cast(d->klass())->element_klass();

    Klass* stype = ObjArrayKlass::cast(s->klass())->element_klass();

    if (stype == bound || stype->is_subtype_of(bound)) {

      // elements are guaranteed to be subtypes, so no check necessary

    } else {

      // slow case: need individual subtype checks

      // note: don't use obj_at_put below because it includes a redundant store check

      }

    }

  }

}

void ObjArrayKlass::copy_array(arrayOop s, int src_pos, arrayOop d,

                               int dst_pos, int length, TRAPS) {

  assert(s->is_objArray(), "must be obj array");

  if (!d->is_objArray()) {

    THROW(vmSymbols::java_lang_ArrayStoreException());

  }

  // Check is all offsets and lengths are non negative

  if (src_pos < 0 || dst_pos < 0 || length < 0) {

    THROW(vmSymbols::java_lang_ArrayIndexOutOfBoundsException());

  }

  // Check if the ranges are valid

  if  ( (((unsigned int) length + (unsigned int) src_pos) > (unsigned int) s->length())

     || (((unsigned int) length + (unsigned int) dst_pos) > (unsigned int) d->length()) ) {

    THROW(vmSymbols::java_lang_ArrayIndexOutOfBoundsException());

  }

  // Special case. Boundary cases must be checked first

  // This allows the following call: copy_array(s, s.length(), d.length(), 0).

  // This is correct, since the position is supposed to be an 'in between point', i.e., s.length(),

  // points to the right of the last element.

  if (length==0) {

    return;

  }

  if (UseCompressedOops) {

    narrowOop* const src = objArrayOop(s)->obj_at_addr<narrowOop>(src_pos);

    narrowOop* const dst = objArrayOop(d)->obj_at_addr<narrowOop>(dst_pos);

    do_copy<narrowOop>(s, src, d, dst, length, CHECK);

  } else {

    oop* const src = objArrayOop(s)->obj_at_addr<oop>(src_pos);

    oop* const dst = objArrayOop(d)->obj_at_addr<oop>(dst_pos);

    do_copy<oop> (s, src, d, dst, length, CHECK);

  }

}

Klass* ObjArrayKlass::array_klass_impl(bool or_null, int n, TRAPS) {

  assert(dimension() <= n, "check order of chain");

  int dim = dimension();

  if (dim == n) return this;

  // lock-free read needs acquire semantics

  if (higher_dimension_acquire() == NULL) {

    if (or_null)  return NULL;

    ResourceMark rm;

    JavaThread *jt = (JavaThread *)THREAD;

    {

      MutexLocker mc(Compile_lock, THREAD);   // for vtables

      // Ensure atomic creation of higher dimensions

      MutexLocker mu(MultiArray_lock, THREAD);

      // Check if another thread beat us

      if (higher_dimension() == NULL) {

        // Create multi-dim klass object and link them together

        Klass* k =

          ObjArrayKlass::allocate_objArray_klass(class_loader_data(), dim + 1, this, CHECK_NULL);

        ObjArrayKlass* ak = ObjArrayKlass::cast(k);

        ak->set_lower_dimension(this);

        // use 'release' to pair with lock-free load

        release_set_higher_dimension(ak);

        assert(ak->is_objArray_klass(), "incorrect initialization of ObjArrayKlass");

      }

    }

  } else {

    CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());

  }

  ObjArrayKlass *ak = ObjArrayKlass::cast(higher_dimension());

  if (or_null) {

    return ak->array_klass_or_null(n);

  }

  return ak->array_klass(n, THREAD);

}

Klass* ObjArrayKlass::array_klass_impl(bool or_null, TRAPS) {

  return array_klass_impl(or_null, dimension() +  1, THREAD);

}

bool ObjArrayKlass::can_be_primary_super_slow() const {

  if (!bottom_klass()->can_be_primary_super())

    // array of interfaces

    return false;

  else

    return Klass::can_be_primary_super_slow();

}

GrowableArray<Klass*>* ObjArrayKlass::compute_secondary_supers(int num_extra_slots) {

  // interfaces = { cloneable_klass, serializable_klass, elemSuper[], ... };

  Array<Klass*>* elem_supers = element_klass()->secondary_supers();

  int num_elem_supers = elem_supers == NULL ? 0 : elem_supers->length();

  int num_secondaries = num_extra_slots + 2 + num_elem_supers;

  if (num_secondaries == 2) {

    // Must share this for correct bootstrapping!

    set_secondary_supers(Universe::the_array_interfaces_array());

    return NULL;

  } else {

    GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(num_elem_supers+2);

    secondaries->push(SystemDictionary::Cloneable_klass());

    secondaries->push(SystemDictionary::Serializable_klass());

    for (int i = 0; i < num_elem_supers; i++) {

      Klass* elem_super = (Klass*) elem_supers->at(i);

      Klass* array_super = elem_super->array_klass_or_null();

      assert(array_super != NULL, "must already have been created");

      secondaries->push(array_super);

    }

    return secondaries;

  }

}

bool ObjArrayKlass::compute_is_subtype_of(Klass* k) {

  if (!k->is_objArray_klass())

    return ArrayKlass::compute_is_subtype_of(k);

  ObjArrayKlass* oak = ObjArrayKlass::cast(k);

  return element_klass()->is_subtype_of(oak->element_klass());

}

void ObjArrayKlass::initialize(TRAPS) {

  bottom_klass()->initialize(THREAD);  // dispatches to either InstanceKlass or TypeArrayKlass

}

void ObjArrayKlass::metaspace_pointers_do(MetaspaceClosure* it) {

  ArrayKlass::metaspace_pointers_do(it);

  it->push(&_element_klass);

  it->push(&_bottom_klass);

}

// JVM support

jint ObjArrayKlass::compute_modifier_flags(TRAPS) const {

  // The modifier for an objectArray is the same as its element

  if (element_klass() == NULL) {

    assert(Universe::is_bootstrapping(), "partial objArray only at startup");

    return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;

  }

  // Return the flags of the bottom element type.

  jint element_flags = bottom_klass()->compute_modifier_flags(CHECK_0);

  return (element_flags & (JVM_ACC_PUBLIC | JVM_ACC_PRIVATE | JVM_ACC_PROTECTED))

                        | (JVM_ACC_ABSTRACT | JVM_ACC_FINAL);

}

ModuleEntry* ObjArrayKlass::module() const {

  assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass");

  // The array is defined in the module of its bottom class

  return bottom_klass()->module();

}

PackageEntry* ObjArrayKlass::package() const {

  assert(bottom_klass() != NULL, "ObjArrayKlass returned unexpected NULL bottom_klass");

  return bottom_klass()->package();

}

// Printing

void ObjArrayKlass::print_on(outputStream* st) const {

#ifndef PRODUCT

  Klass::print_on(st);

  st->print(" - instance klass: ");

  element_klass()->print_value_on(st);

  st->cr();

#endif //PRODUCT

}

void ObjArrayKlass::print_value_on(outputStream* st) const {

  assert(is_klass(), "must be klass");

  element_klass()->print_value_on(st);

  st->print("[]");

}

#ifndef PRODUCT

void ObjArrayKlass::oop_print_on(oop obj, outputStream* st) {

  ArrayKlass::oop_print_on(obj, st);

  assert(obj->is_objArray(), "must be objArray");

  objArrayOop oa = objArrayOop(obj);

  int print_len = MIN2((intx) oa->length(), MaxElementPrintSize);

  for(int index = 0; index < print_len; index++) {

    st->print(" - %3d : ", index);

    oa->obj_at(index)->print_value_on(st);

    st->cr();

  }

  int remaining = oa->length() - print_len;

  if (remaining > 0) {

    st->print_cr(" - <%d more elements, increase MaxElementPrintSize to print>", remaining);

  }

}

#endif //PRODUCT

void ObjArrayKlass::oop_print_value_on(oop obj, outputStream* st) {

  assert(obj->is_objArray(), "must be objArray");

  st->print("a ");

  element_klass()->print_value_on(st);

  int len = objArrayOop(obj)->length();

  st->print("[%d] ", len);

  obj->print_address_on(st);

}

const char* ObjArrayKlass::internal_name() const {

  return external_name();

}

// Verification

void ObjArrayKlass::verify_on(outputStream* st) {

  ArrayKlass::verify_on(st);

  guarantee(element_klass()->is_klass(), "should be klass");

  guarantee(bottom_klass()->is_klass(), "should be klass");

  Klass* bk = bottom_klass();

  guarantee(bk->is_instance_klass() || bk->is_typeArray_klass(),  "invalid bottom klass");

}

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

  ArrayKlass::oop_verify_on(obj, st);

  guarantee(obj->is_objArray(), "must be objArray");

  objArrayOop oa = objArrayOop(obj);

  for(int index = 0; index < oa->length(); index++) {

    guarantee(oopDesc::is_oop_or_null(oa->obj_at(index)), "should be oop");

  }

}