/*

 * 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 "asm/macroAssembler.inline.hpp"

#include "gc/shared/barrierSet.hpp"

#include "gc/shared/cardTable.hpp"

#include "gc/shared/cardTableBarrierSet.hpp"

#include "gc/shared/cardTableBarrierSetAssembler.hpp"

#include "gc/shared/collectedHeap.hpp"

#include "runtime/globals.hpp"

#define __ masm->

#ifdef PRODUCT

#define BLOCK_COMMENT(str) /* nothing */

#else

#define BLOCK_COMMENT(str) __ block_comment(str)

#endif

#define BIND(label) bind(label); BLOCK_COMMENT(#label ":")

void CardTableBarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators,

                                                                    Register addr, Register count, Register tmp) {

  BLOCK_COMMENT("CardTablePostBarrier");

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

  CardTable* ct = ctbs->card_table();

  assert(sizeof(*ct->byte_map_base()) == sizeof(jbyte), "adjust this code");

  Label L_cardtable_loop, L_done;

  __ cbz_32(count, L_done); // zero count - nothing to do

  __ add_ptr_scaled_int32(count, addr, count, LogBytesPerHeapOop);

  __ sub(count, count, BytesPerHeapOop);                            // last addr

  __ logical_shift_right(addr, addr, CardTable::card_shift);

  __ logical_shift_right(count, count, CardTable::card_shift);

  __ sub(count, count, addr); // nb of cards

  // warning: Rthread has not been preserved

  __ mov_address(tmp, (address) ct->byte_map_base(), symbolic_Relocation::card_table_reference);

  __ add(addr,tmp, addr);

  Register zero = __ zero_register(tmp);

  __ BIND(L_cardtable_loop);

  __ strb(zero, Address(addr, 1, post_indexed));

  __ subs(count, count, 1);

  __ b(L_cardtable_loop, ge);

  __ BIND(L_done);

}