/*

 * 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/g1/g1BarrierSet.hpp"

#include "gc/g1/g1BarrierSetAssembler.hpp"

#include "gc/g1/g1CardTable.hpp"

#include "gc/g1/heapRegion.hpp"

#include "interpreter/interp_masm.hpp"

#include "runtime/sharedRuntime.hpp"

#include "runtime/thread.hpp"

#include "utilities/macros.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 G1BarrierSetAssembler::gen_write_ref_array_pre_barrier(MacroAssembler* masm, DecoratorSet decorators,

                                                            Register addr, Register count, int callee_saved_regs) {

  bool dest_uninitialized = (decorators & AS_DEST_NOT_INITIALIZED) != 0;

  if (!dest_uninitialized) {

    assert( addr->encoding() < callee_saved_regs, "addr must be saved");

    assert(count->encoding() < callee_saved_regs, "count must be saved");

    BLOCK_COMMENT("PreBarrier");

#ifdef AARCH64

    callee_saved_regs = align_up(callee_saved_regs, 2);

    for (int i = 0; i < callee_saved_regs; i += 2) {

      __ raw_push(as_Register(i), as_Register(i+1));

    }

#else

    RegisterSet saved_regs = RegisterSet(R0, as_Register(callee_saved_regs-1));

    __ push(saved_regs | R9ifScratched);

#endif // AARCH64

    if (addr != R0) {

      assert_different_registers(count, R0);

      __ mov(R0, addr);

    }

#ifdef AARCH64

    __ zero_extend(R1, count, 32); // G1BarrierSet::write_ref_array_pre_*_entry takes size_t

#else

    if (count != R1) {

      __ mov(R1, count);

    }

#endif // AARCH64

    if (UseCompressedOops) {

      __ call(CAST_FROM_FN_PTR(address, G1BarrierSet::write_ref_array_pre_narrow_oop_entry));

    } else {

      __ call(CAST_FROM_FN_PTR(address, G1BarrierSet::write_ref_array_pre_oop_entry));

    }

#ifdef AARCH64

    for (int i = callee_saved_regs - 2; i >= 0; i -= 2) {

      __ raw_pop(as_Register(i), as_Register(i+1));

    }

#else

    __ pop(saved_regs | R9ifScratched);

#endif // AARCH64

  }

}

void G1BarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators,

                                                             Register addr, Register count, Register tmp) {

  BLOCK_COMMENT("G1PostBarrier");

  if (addr != R0) {

    assert_different_registers(count, R0);

    __ mov(R0, addr);

  }

#ifdef AARCH64

  __ zero_extend(R1, count, 32); // G1BarrierSet::write_ref_array_post_entry takes size_t

#else

  if (count != R1) {

    __ mov(R1, count);

  }

#if R9_IS_SCRATCHED

  // Safer to save R9 here since callers may have been written

  // assuming R9 survives. This is suboptimal but is not in

  // general worth optimizing for the few platforms where R9

  // is scratched. Note that the optimization might not be to

  // difficult for this particular call site.

  __ push(R9);

#endif // !R9_IS_SCRATCHED

#endif // !AARCH64

  __ call(CAST_FROM_FN_PTR(address, G1BarrierSet::write_ref_array_post_entry));

#ifndef AARCH64

#if R9_IS_SCRATCHED

  __ pop(R9);

#endif // !R9_IS_SCRATCHED

#endif // !AARCH64

}