/*

 * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

#include "incls/_precompiled.incl"

#include "incls/_bytecode.cpp.incl"

// Implementation of Bytecode

// Should eventually get rid of these functions and use ThisRelativeObj methods instead

void Bytecode::set_code(Bytecodes::Code code) {

  Bytecodes::check(code);

  *addr_at(0) = u_char(code);

}

bool Bytecode::check_must_rewrite() const {

  assert(Bytecodes::can_rewrite(code()), "post-check only");

  // Some codes are conditionally rewriting.  Look closely at them.

  switch (code()) {

  case Bytecodes::_aload_0:

    // Even if RewriteFrequentPairs is turned on,

    // the _aload_0 code might delay its rewrite until

    // a following _getfield rewrites itself.

    return false;

  case Bytecodes::_lookupswitch:

    return false;  // the rewrite is not done by the interpreter

  case Bytecodes::_new:

    // (Could actually look at the class here, but the profit would be small.)

    return false;  // the rewrite is not always done

  }

  // No other special cases.

  return true;

}

// Implementation of Bytecode_tableupswitch

int Bytecode_tableswitch::dest_offset_at(int i) const {

  address x = aligned_addr_at(1);

  int x2 = aligned_offset(1 + (3 + i)*jintSize);

  int val = java_signed_word_at(x2);

  return java_signed_word_at(aligned_offset(1 + (3 + i)*jintSize));

}

// Implementation of Bytecode_invoke

void Bytecode_invoke::verify() const {

  Bytecodes::Code bc = adjusted_invoke_code();

  assert(is_valid(), "check invoke");

}

symbolOop Bytecode_invoke::signature() const {

  constantPoolOop constants = method()->constants();

  return constants->signature_ref_at(index());

}

symbolOop Bytecode_invoke::name() const {

  constantPoolOop constants = method()->constants();

  return constants->name_ref_at(index());

}

BasicType Bytecode_invoke::result_type(Thread *thread) const {

  symbolHandle sh(thread, signature());

  ResultTypeFinder rts(sh);

  rts.iterate();

  return rts.type();

}

methodHandle Bytecode_invoke::static_target(TRAPS) {

  methodHandle m;

  KlassHandle resolved_klass;

  constantPoolHandle constants(THREAD, _method->constants());

    LinkResolver::resolve_method(m, resolved_klass, constants, index(), CHECK_(methodHandle()));

  } else {

    LinkResolver::resolve_interface_method(m, resolved_klass, constants, index(), CHECK_(methodHandle()));

  }

  return m;

}

int Bytecode_invoke::index() const {

  // Note:  Rewriter::rewrite changes the Java_u2 of an invokedynamic to a native_u4,

  // at the same time it allocates per-call-site CP cache entries.

  if (has_giant_index())

    return Bytes::get_native_u4(bcp() + 1);

  else

    return Bytes::get_Java_u2(bcp() + 1);

}

// Implementation of Bytecode_static

void Bytecode_static::verify() const {

  assert(Bytecodes::java_code(code()) == Bytecodes::_putstatic

      || Bytecodes::java_code(code()) == Bytecodes::_getstatic, "check static");

}

BasicType Bytecode_static::result_type(methodOop method) const {

  int index = java_hwrd_at(1);

  constantPoolOop constants = method->constants();

  symbolOop field_type = constants->signature_ref_at(index);

  BasicType basic_type = FieldType::basic_type(field_type);

  return basic_type;

}

// Implementation of Bytecode_field

void Bytecode_field::verify() const {

  Bytecodes::Code stdc = Bytecodes::java_code(code());

  assert(stdc == Bytecodes::_putstatic || stdc == Bytecodes::_getstatic ||

         stdc == Bytecodes::_putfield  || stdc == Bytecodes::_getfield, "check field");

}

bool Bytecode_field::is_static() const {

  Bytecodes::Code stdc = Bytecodes::java_code(code());

  return stdc == Bytecodes::_putstatic || stdc == Bytecodes::_getstatic;

}

int Bytecode_field::index() const {

  return java_hwrd_at(1);

}

// Implementation of Bytecodes loac constant

int Bytecode_loadconstant::index() const {

  Bytecodes::Code stdc = Bytecodes::java_code(code());

  return stdc == Bytecodes::_ldc ? java_byte_at(1) : java_hwrd_at(1);

}

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

// Non-product code

#ifndef PRODUCT

void Bytecode_lookupswitch::verify() const {

  switch (Bytecodes::java_code(code())) {

    case Bytecodes::_lookupswitch:

      { int i = number_of_pairs() - 1;

        while (i-- > 0) {

          assert(pair_at(i)->match() < pair_at(i+1)->match(), "unsorted table entries");

        }

      }

      break;

    default:

      fatal("not a lookupswitch bytecode");

  }

}

void Bytecode_tableswitch::verify() const {

  switch (Bytecodes::java_code(code())) {

    case Bytecodes::_tableswitch:

      { int lo = low_key();

        int hi = high_key();

        assert (hi >= lo, "incorrect hi/lo values in tableswitch");

        int i  = hi - lo - 1 ;

        while (i-- > 0) {

          // no special check needed

        }

      }

      break;

    default:

      fatal("not a tableswitch bytecode");

  }

}

#endif