/*
 * Copyright (c) 2015, 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 "interpreter/interpreter.hpp"
#include "oops/oop.inline.hpp"
#include "oops/fieldStreams.hpp"
#include "oops/method.hpp"
#include "oops/objArrayKlass.hpp"
#include "oops/valueKlass.hpp"
#include "oops/valueArrayKlass.hpp"

Method* ValueKlass::factory_method() const {
  for (int i = 0; i < methods()->length(); i++) {
    ConstMethod* cm = methods()->at(i)->constMethod();
    if (cm->has_valuefactory_parameter_mapping()) {
      return methods()->at(i);
    }
  }
  return NULL;
}

int ValueKlass::first_field_offset() {
#ifdef ASSERT
  instanceKlassHandle k(this);
  int first_offset = INT_MAX;
  for (JavaFieldStream fs(k()); !fs.done(); fs.next()) {
    if (fs.offset() < first_offset) first_offset= fs.offset();
  }
#endif
  int base_offset = instanceOopDesc::base_offset_in_bytes();
  // The first field of value types is aligned on a long boundary
  base_offset = align_size_up(base_offset, BytesPerLong);
  assert(base_offset = first_offset, "inconsistent offsets");
  return base_offset;
}

bool ValueKlass::is_atomic() {
  return (nonstatic_field_size() * heapOopSize) <= longSize;
}

int ValueKlass::nonstatic_oop_count() {
  int oops = 0;
  int map_count = nonstatic_oop_map_count();
  OopMapBlock* block = start_of_nonstatic_oop_maps();
  OopMapBlock* end = block + map_count;
  while (block != end) {
    oops += block->count();
    block++;
  }
  return oops;
}

// Arrays of...

bool ValueKlass::flatten_array() {
  if (!ValueArrayFlatten) {
    return false;
  }

  int elem_bytes = raw_value_byte_size();
  // Too big
  if ((ValueArrayElemMaxFlatSize >= 0) && (elem_bytes > ValueArrayElemMaxFlatSize)) {
    return false;
  }
  // Too many embedded oops
  if ((ValueArrayElemMaxFlatOops >= 0) && (nonstatic_oop_count() > ValueArrayElemMaxFlatOops)) {
    return false;
  }

  return true;
}


Klass* ValueKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
  if (!ValueKlass::cast(this_k())->flatten_array()) {
    return InstanceKlass::array_klass_impl(this_k, or_null, n, THREAD);
  }

  // Basically the same as instanceKlass, but using "ValueArrayKlass::allocate_klass"
  if (this_k->array_klasses() == NULL) {
    if (or_null) return NULL;

    ResourceMark rm;
    JavaThread *jt = (JavaThread *)THREAD;
    {
      // Atomic creation of array_klasses
      MutexLocker mc(Compile_lock, THREAD);   // for vtables
      MutexLocker ma(MultiArray_lock, THREAD);

      // Check if update has already taken place
      if (this_k->array_klasses() == NULL) {
        Klass* ak;
        if (ValueKlass::cast(this_k())->is_atomic() || (!ValueArrayAtomicAccess)) {
          ak = ValueArrayKlass::allocate_klass(this_k, CHECK_NULL);
        }
        else {
          ak = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
        }
        this_k->set_array_klasses(ak);
      }
    }
  }
  // _this will always be set at this point
  ArrayKlass* ak = ArrayKlass::cast(this_k->array_klasses());
  if (or_null) {
    return ak->array_klass_or_null(n);
  }
  return ak->array_klass(n, THREAD);
}

Klass* ValueKlass::array_klass_impl(bool or_null, int n, TRAPS) {
  instanceKlassHandle this_k(THREAD, this);
  return array_klass_impl(this_k, or_null, n, THREAD);
}

Klass* ValueKlass::array_klass_impl(bool or_null, TRAPS) {
  return array_klass_impl(or_null, 1, THREAD);
}

/*
 * Store the value of this klass contained with src into dst.
 *
 * This operation is appropriate for use from vastore, vaload and putfield (for values)
 *
 * GC barriers currently can lock with no safepoint check and allocate c-heap,
 * so raw point is "safe" for now.
 *
 * Going forward, look to use machine generated (stub gen or bc) version for most used klass layouts
 */
void ValueKlass::value_store(void* src, void* dst, bool dst_heap, bool dst_uninitialized) {
  // So the raw "memcpy" bytes size...
  size_t raw_byte_size = raw_value_byte_size();

  if (contains_oops() && dst_heap) {
    // src/dst aren't oops, need offset to adjust oop map offset
    int oop_offset = valueOopDescBase();

    // Pre-barriers...
    OopMapBlock* map = start_of_nonstatic_oop_maps();
    OopMapBlock* const end = map + nonstatic_oop_map_count();
    while (map != end) {
      // Shame we can't just use the existing oop iterator...src/dst aren't oop
      uintptr_t doop_address = ((uintptr_t)dst) + (map->offset() - oop_offset);
      if (UseCompressedOops) {
        oopDesc::bs()->write_ref_array_pre((narrowOop*) doop_address, map->count(), dst_uninitialized);
      }
      else {
        oopDesc::bs()->write_ref_array_pre((oop*) doop_address, map->count(), dst_uninitialized);
      }
      map++;
    }

    // Actual store...
    // oop atomic copy, even if both dst & src don't require atomic ?
    Copy::conjoint_jlongs_atomic((jlong*)src, (jlong*)dst, raw_byte_size / sizeof(jlong));

    // Post-barriers...
    map = start_of_nonstatic_oop_maps();
    while (map != end) {
      uintptr_t doop_address = ((uintptr_t)dst) + (map->offset() - oop_offset);
      oopDesc::bs()->write_ref_array((HeapWord*) doop_address, map->count());
      map++;
    }
  }
  else {   // Primitive-only case...
    memcpy(dst, src, raw_byte_size); // Actual store
  }

}