/*

 * Copyright (c) 1999, 2013, 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 "ci/ciArray.hpp"

#include "ci/ciArrayKlass.hpp"

#include "ci/ciConstant.hpp"

#include "ci/ciKlass.hpp"

#include "ci/ciUtilities.hpp"

#include "oops/objArrayOop.hpp"

#include "oops/typeArrayOop.hpp"

// ciArray

//

// This class represents an arrayOop in the HotSpot virtual

// machine.

static BasicType fixup_element_type(BasicType bt) {

  if (bt == T_ARRAY)    return T_OBJECT;

  if (bt == T_BOOLEAN)  return T_BYTE;

  return bt;

}

ciConstant ciArray::element_value_impl(BasicType elembt,

                                       arrayOop ary,

                                       int index) {

  if (ary == NULL)

    return ciConstant();

  assert(ary->is_array(), "");

  if (index < 0 || index >= ary->length())

    return ciConstant();

  ArrayKlass* ak = (ArrayKlass*) ary->klass();

  BasicType abt = ak->element_type();

  if (fixup_element_type(elembt) !=

      fixup_element_type(abt))

    return ciConstant();

  switch (elembt) {

  case T_ARRAY:

  case T_OBJECT:

    {

      assert(ary->is_objArray(), "");

      objArrayOop objary = (objArrayOop) ary;

      oop elem = objary->obj_at(index);

      ciEnv* env = CURRENT_ENV;

      ciObject* box = env->get_object(elem);

      return ciConstant(T_OBJECT, box);

    }

  }

  assert(ary->is_typeArray(), "");

  typeArrayOop tary = (typeArrayOop) ary;

  jint value = 0;

  switch (elembt) {

  case T_LONG:          return ciConstant(tary->long_at(index));

  case T_FLOAT:         return ciConstant(tary->float_at(index));

  case T_DOUBLE:        return ciConstant(tary->double_at(index));

  default:              return ciConstant();

  case T_BYTE:          value = tary->byte_at(index);           break;

  case T_BOOLEAN:       value = tary->byte_at(index) & 1;       break;

  case T_SHORT:         value = tary->short_at(index);          break;

  case T_CHAR:          value = tary->char_at(index);           break;

  case T_INT:           value = tary->int_at(index);            break;

  }

  return ciConstant(elembt, value);

}

// ------------------------------------------------------------------

// ciArray::element_value

//

// Current value of an element.

// Returns T_ILLEGAL if there is no element at the given index.

ciConstant ciArray::element_value(int index) {

  BasicType elembt = element_basic_type();

  GUARDED_VM_ENTRY(

    return element_value_impl(elembt, get_arrayOop(), index);

  )

}

// ------------------------------------------------------------------

// ciArray::element_value_by_offset

//

// Current value of an element at the specified offset.

// Returns T_ILLEGAL if there is no element at the given offset.

ciConstant ciArray::element_value_by_offset(intptr_t element_offset) {

  BasicType elembt = element_basic_type();

  intptr_t shift  = exact_log2(type2aelembytes(elembt));

  intptr_t header = arrayOopDesc::base_offset_in_bytes(elembt);

  intptr_t index = (element_offset - header) >> shift;

  intptr_t offset = header + ((intptr_t)index << shift);

  if (offset != element_offset || index != (jint)index)

    return ciConstant();

  return element_value((jint) index);

}

// ------------------------------------------------------------------

// ciArray::print_impl

//

// Implementation of the print method.

void ciArray::print_impl(outputStream* st) {

  st->print(" length=%d type=", length());

  klass()->print(st);

}