/*

 * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.

 * Copyright 2009 Red Hat, Inc.

 * 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/ciInstance.hpp"

#include "ci/ciStreams.hpp"

#include "shark/sharkBuilder.hpp"

#include "shark/sharkConstant.hpp"

#include "shark/sharkValue.hpp"

using namespace llvm;

SharkConstant* SharkConstant::for_ldc(ciBytecodeStream *iter) {

  ciConstant constant = iter->get_constant();

  ciType *type = NULL;

  if (constant.basic_type() == T_OBJECT) {

    ciEnv *env = ciEnv::current();

    assert(constant.as_object()->klass() == env->String_klass()

           || constant.as_object()->klass() == env->Class_klass()

           || constant.as_object()->klass()->is_subtype_of(env->MethodType_klass())

           || constant.as_object()->klass()->is_subtype_of(env->MethodHandle_klass()), "should be");

    type = constant.as_object()->klass();

  }

  return new SharkConstant(constant, type);

}

SharkConstant* SharkConstant::for_field(ciBytecodeStream *iter) {

  bool will_link;

  ciField *field = iter->get_field(will_link);

  assert(will_link, "typeflow responsibility");

  return new SharkConstant(field->constant_value(), field->type());

}

SharkConstant::SharkConstant(ciConstant constant, ciType *type) {

  SharkValue *value = NULL;

  switch (constant.basic_type()) {

  case T_BOOLEAN:

  case T_BYTE:

  case T_CHAR:

  case T_SHORT:

  case T_INT:

    value = SharkValue::jint_constant(constant.as_int());

    break;

  case T_LONG:

    value = SharkValue::jlong_constant(constant.as_long());

    break;

  case T_FLOAT:

    value = SharkValue::jfloat_constant(constant.as_float());

    break;

  case T_DOUBLE:

    value = SharkValue::jdouble_constant(constant.as_double());

    break;

  case T_OBJECT:

  case T_ARRAY:

    break;

  case T_ILLEGAL:

    // out of memory

    _is_loaded = false;

    return;

  default:

    tty->print_cr("Unhandled type %s", type2name(constant.basic_type()));

    ShouldNotReachHere();

  }

  // Handle primitive types.  We create SharkValues for these

  // now; doing so doesn't emit any code, and it allows us to

  // delegate a bunch of stuff to the SharkValue code.

  if (value) {

    _value       = value;

    _is_loaded   = true;

    _is_nonzero  = value->zero_checked();

    _is_two_word = value->is_two_word();

    return;

  }

  // Handle reference types.  This is tricky because some

  // ciObjects are psuedo-objects that refer to oops which

  // have yet to be created.  We need to spot the unloaded

  // objects (which differ between ldc* and get*, thanks!)

  ciObject *object = constant.as_object();

  assert(type != NULL, "shouldn't be");

  if ((! object->is_null_object()) && object->klass() == ciEnv::current()->Class_klass()) {

    ciKlass *klass = object->klass();

    if (! klass->is_loaded()) {

      _is_loaded = false;

      return;

    }

  }

  if (object->is_null_object() || ! object->can_be_constant() || ! object->is_loaded()) {

    _is_loaded = false;

    return;

  }

  _value       = NULL;

  _object      = object;

  _type        = type;

  _is_loaded   = true;

  _is_nonzero  = true;

  _is_two_word = false;

}