/*

 * Copyright (c) 2018, 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 "gc/shared/c1/cardTableBarrierSetC1.hpp"

#include "gc/shared/cardTable.hpp"

#include "gc/shared/cardTableBarrierSet.hpp"

#include "utilities/macros.hpp"

#ifdef ASSERT

#define __ gen->lir(__FILE__, __LINE__)->

#else

#define __ gen->lir()->

#endif

void CardTableBarrierSetC1::post_barrier(LIRAccess& access, LIR_OprDesc* addr, LIR_OprDesc* new_val) {

  DecoratorSet decorators = access.decorators();

  LIRGenerator* gen = access.gen();

  bool in_heap = (decorators & IN_HEAP) != 0;

  if (!in_heap) {

    return;

  }

  BarrierSet* bs = BarrierSet::barrier_set();

  CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs);

  CardTable* ct = ctbs->card_table();

  LIR_Const* card_table_base = new LIR_Const(ct->byte_map_base());

  if (addr->is_address()) {

    LIR_Address* address = addr->as_address_ptr();

    // ptr cannot be an object because we use this barrier for array card marks

    // and addr can point in the middle of an array.

    LIR_Opr ptr = gen->new_pointer_register();

    if (!address->index()->is_valid() && address->disp() == 0) {

      __ move(address->base(), ptr);

    } else {

      assert(address->disp() != max_jint, "lea doesn't support patched addresses!");

      __ leal(addr, ptr);

    }

    addr = ptr;

  }

  assert(addr->is_register(), "must be a register at this point");

#ifdef CARDTABLEBARRIERSET_POST_BARRIER_HELPER

  gen->CardTableBarrierSet_post_barrier_helper(addr, card_table_base);

#else

  LIR_Opr tmp = gen->new_pointer_register();

  if (TwoOperandLIRForm) {

    __ move(addr, tmp);

    __ unsigned_shift_right(tmp, CardTable::card_shift, tmp);

  } else {

    __ unsigned_shift_right(addr, CardTable::card_shift, tmp);

  }

  LIR_Address* card_addr;

  if (gen->can_inline_as_constant(card_table_base)) {

    card_addr = new LIR_Address(tmp, card_table_base->as_jint(), T_BYTE);

  } else {

    card_addr = new LIR_Address(tmp, gen->load_constant(card_table_base), T_BYTE);

  }

  LIR_Opr dirty = LIR_OprFact::intConst(CardTable::dirty_card_val());

  if (UseCondCardMark) {

    LIR_Opr cur_value = gen->new_register(T_INT);

    if (ct->scanned_concurrently()) {

      __ membar_storeload();

    }

    __ move(card_addr, cur_value);

    LabelObj* L_already_dirty = new LabelObj();

    __ cmp(lir_cond_equal, cur_value, dirty);

    __ branch(lir_cond_equal, T_BYTE, L_already_dirty->label());

    __ move(dirty, card_addr);

    __ branch_destination(L_already_dirty->label());

  } else {

    if (ct->scanned_concurrently()) {

      __ membar_storestore();

    }

    __ move(dirty, card_addr);

  }

#endif

}