path: root/src/share/vm/oops/objArrayKlassKlass.cpp

/*
 * Copyright (c) 1997, 2010, 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
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 * questions.
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#include "precompiled.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/systemDictionary.hpp"
#include "gc_implementation/shared/markSweep.inline.hpp"
#include "gc_interface/collectedHeap.inline.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/objArrayKlassKlass.hpp"
#include "oops/oop.inline.hpp"
#include "oops/oop.inline2.hpp"

klassOop objArrayKlassKlass::create_klass(TRAPS) {
  objArrayKlassKlass o;
  KlassHandle h_this_klass(THREAD, Universe::klassKlassObj());
  KlassHandle k = base_create_klass(h_this_klass, header_size(), o.vtbl_value(), CHECK_0);
  assert(k()->size() == align_object_size(header_size()), "wrong size for object");
  java_lang_Class::create_mirror(k, CHECK_0); // Allocate mirror
  return k();
}

klassOop objArrayKlassKlass::allocate_system_objArray_klass(TRAPS) {
  // system_objArrays have no instance klass, so allocate with fake class, then reset to NULL
  KlassHandle kk(THREAD, Universe::intArrayKlassObj());
  klassOop k = allocate_objArray_klass(1, kk, CHECK_0);
  objArrayKlass* tk = (objArrayKlass*) k->klass_part();
  tk->set_element_klass(NULL);
  tk->set_bottom_klass(NULL);
  return k;
}


klassOop objArrayKlassKlass::allocate_objArray_klass(int n, KlassHandle element_klass, TRAPS) {
  objArrayKlassKlassHandle this_oop(THREAD, as_klassOop());
  return allocate_objArray_klass_impl(this_oop, n, element_klass, THREAD);
}

klassOop objArrayKlassKlass::allocate_objArray_klass_impl(objArrayKlassKlassHandle this_oop,
                                                          int n, KlassHandle element_klass, TRAPS) {

  // Eagerly allocate the direct array supertype.
  KlassHandle super_klass = KlassHandle();
  if (!Universe::is_bootstrapping()) {
    KlassHandle element_super (THREAD, element_klass->super());
    if (element_super.not_null()) {
      // The element type has a direct super.  E.g., String[] has direct super of Object[].
      super_klass = KlassHandle(THREAD, element_super->array_klass_or_null());
      bool supers_exist = super_klass.not_null();
      // Also, see if the element has secondary supertypes.
      // We need an array type for each.
      objArrayHandle element_supers = objArrayHandle(THREAD,
                                            element_klass->secondary_supers());
      for( int i = element_supers->length()-1; i >= 0; i-- ) {
        klassOop elem_super = (klassOop) element_supers->obj_at(i);
        if (Klass::cast(elem_super)->array_klass_or_null() == NULL) {
          supers_exist = false;
          break;
        }
      }
      if (!supers_exist) {
        // Oops.  Not allocated yet.  Back out, allocate it, and retry.
#ifndef PRODUCT
        if (WizardMode) {
          tty->print_cr("Must retry array klass creation for depth %d",n);
        }
#endif
        KlassHandle ek;
        {
          MutexUnlocker mu(MultiArray_lock);
          MutexUnlocker mc(Compile_lock);   // for vtables
          klassOop sk = element_super->array_klass(CHECK_0);
          super_klass = KlassHandle(THREAD, sk);
          for( int i = element_supers->length()-1; i >= 0; i-- ) {
            KlassHandle elem_super (THREAD, element_supers->obj_at(i));
            elem_super->array_klass(CHECK_0);
          }
          // Now retry from the beginning
          klassOop klass_oop = element_klass->array_klass(n, CHECK_0);
          // Create a handle because the enclosing brace, when locking
          // can cause a gc.  Better to have this function return a Handle.
          ek = KlassHandle(THREAD, klass_oop);
        }  // re-lock
        return ek();
      }
    } else {
      // The element type is already Object.  Object[] has direct super of Object.
      super_klass = KlassHandle(THREAD, SystemDictionary::Object_klass());
    }
  }

  // Create type name for klass (except for symbol arrays, since symbolKlass
  // does not have a name).  This will potentially allocate an object, cause
  // GC, and all other kinds of things.  Hence, this must be done before we
  // get a handle to the new objArrayKlass we want to construct.  We cannot
  // block while holding a handling to a partly initialized object.
  symbolHandle name = symbolHandle();

  if (!element_klass->oop_is_symbol()) {
    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->oop_is_instance()) { // 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->oop_is_instance()) {
      new_str[idx++] = ';';
    }
    new_str[idx++] = '\0';
    name = oopFactory::new_symbol_handle(new_str, CHECK_0);
  }

  objArrayKlass o;
  arrayKlassHandle k = arrayKlass::base_create_array_klass(o.vtbl_value(),
                                                           objArrayKlass::header_size(),
                                                          this_oop,
                                                           CHECK_0);


  // Initialize instance variables
  objArrayKlass* oak = objArrayKlass::cast(k());
  oak->set_dimension(n);
  oak->set_element_klass(element_klass());
  oak->set_name(name());

  klassOop bk;
  if (element_klass->oop_is_objArray()) {
    bk = objArrayKlass::cast(element_klass())->bottom_klass();
  } else {
    bk = element_klass();
  }
  assert(bk != NULL && (Klass::cast(bk)->oop_is_instance() || Klass::cast(bk)->oop_is_typeArray()), "invalid bottom klass");
  oak->set_bottom_klass(bk);

  oak->set_layout_helper(array_layout_helper(T_OBJECT));
  assert(oak->oop_is_javaArray(), "sanity");
  assert(oak->oop_is_objArray(), "sanity");

  // Call complete_create_array_klass after all instance variables has been initialized.
  arrayKlass::complete_create_array_klass(k, super_klass, CHECK_0);

  return k();
}


void objArrayKlassKlass::oop_follow_contents(oop obj) {
  assert(obj->is_klass(), "must be klass");
  assert(klassOop(obj)->klass_part()->oop_is_objArray_slow(), "must be obj array");

  objArrayKlass* oak = objArrayKlass::cast((klassOop)obj);
  MarkSweep::mark_and_push(oak->element_klass_addr());
  MarkSweep::mark_and_push(oak->bottom_klass_addr());

  arrayKlassKlass::oop_follow_contents(obj);
}

#ifndef SERIALGC
void objArrayKlassKlass::oop_follow_contents(ParCompactionManager* cm,
                                             oop obj) {
  assert(obj->is_klass(), "must be klass");
  assert(klassOop(obj)->klass_part()->oop_is_objArray_slow(), "must be obj array");

  objArrayKlass* oak = objArrayKlass::cast((klassOop)obj);
  PSParallelCompact::mark_and_push(cm, oak->element_klass_addr());
  PSParallelCompact::mark_and_push(cm, oak->bottom_klass_addr());

  arrayKlassKlass::oop_follow_contents(cm, obj);
}
#endif // SERIALGC


int objArrayKlassKlass::oop_adjust_pointers(oop obj) {
  assert(obj->is_klass(), "must be klass");
  assert(klassOop(obj)->klass_part()->oop_is_objArray_slow(), "must be obj array");

  objArrayKlass* oak = objArrayKlass::cast((klassOop)obj);
  MarkSweep::adjust_pointer(oak->element_klass_addr());
  MarkSweep::adjust_pointer(oak->bottom_klass_addr());

  return arrayKlassKlass::oop_adjust_pointers(obj);
}



int objArrayKlassKlass::oop_oop_iterate(oop obj, OopClosure* blk) {
  assert(obj->is_klass(), "must be klass");
  assert(klassOop(obj)->klass_part()->oop_is_objArray_slow(), "must be obj array");

  objArrayKlass* oak = objArrayKlass::cast((klassOop)obj);
  blk->do_oop(oak->element_klass_addr());
  blk->do_oop(oak->bottom_klass_addr());

  return arrayKlassKlass::oop_oop_iterate(obj, blk);
}


int
objArrayKlassKlass::oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) {
  assert(obj->is_klass(), "must be klass");
  assert(klassOop(obj)->klass_part()->oop_is_objArray_slow(), "must be obj array");

  objArrayKlass* oak = objArrayKlass::cast((klassOop)obj);
  oop* addr;
  addr = oak->element_klass_addr();
  if (mr.contains(addr)) blk->do_oop(addr);
  addr = oak->bottom_klass_addr();
  if (mr.contains(addr)) blk->do_oop(addr);

  return arrayKlassKlass::oop_oop_iterate(obj, blk);
}

#ifndef SERIALGC
void objArrayKlassKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
  assert(obj->blueprint()->oop_is_objArrayKlass(),"must be an obj array klass");
}

int objArrayKlassKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
  assert(obj->is_klass(), "must be klass");
  assert(klassOop(obj)->klass_part()->oop_is_objArray_slow(), "must be obj array");

  objArrayKlass* oak = objArrayKlass::cast((klassOop)obj);
  PSParallelCompact::adjust_pointer(oak->element_klass_addr());
  PSParallelCompact::adjust_pointer(oak->bottom_klass_addr());

  return arrayKlassKlass::oop_update_pointers(cm, obj);
}

int objArrayKlassKlass::oop_update_pointers(ParCompactionManager* cm, oop obj,
                                            HeapWord* beg_addr,
                                            HeapWord* end_addr) {
  assert(obj->is_klass(), "must be klass");
  assert(klassOop(obj)->klass_part()->oop_is_objArray_slow(), "must be obj array");

  oop* p;
  objArrayKlass* oak = objArrayKlass::cast((klassOop)obj);
  p = oak->element_klass_addr();
  PSParallelCompact::adjust_pointer(p, beg_addr, end_addr);
  p = oak->bottom_klass_addr();
  PSParallelCompact::adjust_pointer(p, beg_addr, end_addr);

  return arrayKlassKlass::oop_update_pointers(cm, obj, beg_addr, end_addr);
}
#endif // SERIALGC

#ifndef PRODUCT

// Printing

void objArrayKlassKlass::oop_print_on(oop obj, outputStream* st) {
  assert(obj->is_klass(), "must be klass");
  objArrayKlass* oak = (objArrayKlass*) klassOop(obj)->klass_part();
  klassKlass::oop_print_on(obj, st);
  st->print(" - instance klass: ");
  oak->element_klass()->print_value_on(st);
  st->cr();
}

#endif //PRODUCT

void objArrayKlassKlass::oop_print_value_on(oop obj, outputStream* st) {
  assert(obj->is_klass(), "must be klass");
  objArrayKlass* oak = (objArrayKlass*) klassOop(obj)->klass_part();

  oak->element_klass()->print_value_on(st);
  st->print("[]");
}

const char* objArrayKlassKlass::internal_name() const {
  return "{object array class}";
}


// Verification

void objArrayKlassKlass::oop_verify_on(oop obj, outputStream* st) {
  klassKlass::oop_verify_on(obj, st);
  objArrayKlass* oak = objArrayKlass::cast((klassOop)obj);
  guarantee(oak->element_klass()->is_perm(),  "should be in permspace");
  guarantee(oak->element_klass()->is_klass(), "should be klass");
  guarantee(oak->bottom_klass()->is_perm(),   "should be in permspace");
  guarantee(oak->bottom_klass()->is_klass(),  "should be klass");
  Klass* bk = Klass::cast(oak->bottom_klass());
  guarantee(bk->oop_is_instance() || bk->oop_is_typeArray(),  "invalid bottom klass");
}