z_aarch64.ad

//
// Copyright (c) 2019, 2021, 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.
//
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// or visit www.oracle.com if you need additional information or have any
// questions.
//

source_hpp %{

#include "gc/shared/gc_globals.hpp"
#include "gc/z/c2/zBarrierSetC2.hpp"
#include "gc/z/zThreadLocalData.hpp"

%}

source %{

static void z_load_barrier(MacroAssembler& _masm, const MachNode* node, Address ref_addr, Register ref, Register tmp, uint8_t barrier_data) {
  if (barrier_data == ZLoadBarrierElided) {
    return;
  }
  ZLoadBarrierStubC2* const stub = ZLoadBarrierStubC2::create(node, ref_addr, ref, tmp, barrier_data);
  __ ldr(tmp, Address(rthread, ZThreadLocalData::address_bad_mask_offset()));
  __ andr(tmp, tmp, ref);
  __ cbnz(tmp, *stub->entry());
  __ bind(*stub->continuation());
}

static void z_load_barrier_slow_path(MacroAssembler& _masm, const MachNode* node, Address ref_addr, Register ref, Register tmp) {
  ZLoadBarrierStubC2* const stub = ZLoadBarrierStubC2::create(node, ref_addr, ref, tmp, ZLoadBarrierStrong);
  __ b(*stub->entry());
  __ bind(*stub->continuation());
}

%}

// Load Pointer
instruct zLoadP(iRegPNoSp dst, memory8 mem, rFlagsReg cr)
%{
  match(Set dst (LoadP mem));
  predicate(UseZGC && !needs_acquiring_load(n) && (n->as_Load()->barrier_data() != 0));
  effect(TEMP dst, KILL cr);

  ins_cost(4 * INSN_COST);

  format %{ "ldr  $dst, $mem" %}

  ins_encode %{
    const Address ref_addr = mem2address($mem->opcode(), as_Register($mem$$base), $mem$$index, $mem$$scale, $mem$$disp);
    __ ldr($dst$$Register, ref_addr);
    z_load_barrier(_masm, this, ref_addr, $dst$$Register, rscratch2 /* tmp */, barrier_data());
  %}

  ins_pipe(iload_reg_mem);
%}

// Load Pointer Volatile
instruct zLoadPVolatile(iRegPNoSp dst, indirect mem /* sync_memory */, rFlagsReg cr)
%{
  match(Set dst (LoadP mem));
  predicate(UseZGC && needs_acquiring_load(n) && n->as_Load()->barrier_data() != 0);
  effect(TEMP dst, KILL cr);

  ins_cost(VOLATILE_REF_COST);

  format %{ "ldar  $dst, $mem\t" %}

  ins_encode %{
    __ ldar($dst$$Register, $mem$$Register);
    z_load_barrier(_masm, this, Address($mem$$Register), $dst$$Register, rscratch2 /* tmp */, barrier_data());
  %}

  ins_pipe(pipe_serial);
%}

instruct zCompareAndSwapP(iRegINoSp res, indirect mem, iRegP oldval, iRegP newval, rFlagsReg cr) %{
  match(Set res (CompareAndSwapP mem (Binary oldval newval)));
  match(Set res (WeakCompareAndSwapP mem (Binary oldval newval)));
  predicate(UseZGC && !needs_acquiring_load_exclusive(n) && n->as_LoadStore()->barrier_data() == ZLoadBarrierStrong);
  effect(KILL cr, TEMP_DEF res);

  ins_cost(2 * VOLATILE_REF_COST);

  format %{ "cmpxchg $mem, $oldval, $newval\n\t"
            "cset    $res, EQ" %}

  ins_encode %{
    guarantee($mem$$index == -1 && $mem$$disp == 0, "impossible encoding");
    __ cmpxchg($mem$$Register, $oldval$$Register, $newval$$Register, Assembler::xword,
               false /* acquire */, true /* release */, false /* weak */, rscratch2);
    __ cset($res$$Register, Assembler::EQ);
    if (barrier_data() != ZLoadBarrierElided) {
      Label good;
      __ ldr(rscratch1, Address(rthread, ZThreadLocalData::address_bad_mask_offset()));
      __ andr(rscratch1, rscratch1, rscratch2);
      __ cbz(rscratch1, good);
      z_load_barrier_slow_path(_masm, this, Address($mem$$Register), rscratch2 /* ref */, rscratch1 /* tmp */);
      __ cmpxchg($mem$$Register, $oldval$$Register, $newval$$Register, Assembler::xword,
                 false /* acquire */, true /* release */, false /* weak */, rscratch2);
      __ cset($res$$Register, Assembler::EQ);
      __ bind(good);
    }
  %}

  ins_pipe(pipe_slow);
%}

instruct zCompareAndSwapPAcq(iRegINoSp res, indirect mem, iRegP oldval, iRegP newval, rFlagsReg cr) %{
  match(Set res (CompareAndSwapP mem (Binary oldval newval)));
  match(Set res (WeakCompareAndSwapP mem (Binary oldval newval)));
  predicate(UseZGC && needs_acquiring_load_exclusive(n) && (n->as_LoadStore()->barrier_data() == ZLoadBarrierStrong));
  effect(KILL cr, TEMP_DEF res);

  ins_cost(2 * VOLATILE_REF_COST);

 format %{ "cmpxchg $mem, $oldval, $newval\n\t"
           "cset    $res, EQ" %}

  ins_encode %{
    guarantee($mem$$index == -1 && $mem$$disp == 0, "impossible encoding");
    __ cmpxchg($mem$$Register, $oldval$$Register, $newval$$Register, Assembler::xword,
               true /* acquire */, true /* release */, false /* weak */, rscratch2);
    __ cset($res$$Register, Assembler::EQ);
    if (barrier_data() != ZLoadBarrierElided) {
      Label good;
      __ ldr(rscratch1, Address(rthread, ZThreadLocalData::address_bad_mask_offset()));
      __ andr(rscratch1, rscratch1, rscratch2);
      __ cbz(rscratch1, good);
      z_load_barrier_slow_path(_masm, this, Address($mem$$Register), rscratch2 /* ref */, rscratch1 /* tmp */ );
      __ cmpxchg($mem$$Register, $oldval$$Register, $newval$$Register, Assembler::xword,
                 true /* acquire */, true /* release */, false /* weak */, rscratch2);
      __ cset($res$$Register, Assembler::EQ);
      __ bind(good);
    }
  %}

  ins_pipe(pipe_slow);
%}

instruct zCompareAndExchangeP(iRegPNoSp res, indirect mem, iRegP oldval, iRegP newval, rFlagsReg cr) %{
  match(Set res (CompareAndExchangeP mem (Binary oldval newval)));
  predicate(UseZGC && !needs_acquiring_load_exclusive(n) && n->as_LoadStore()->barrier_data() == ZLoadBarrierStrong);
  effect(TEMP_DEF res, KILL cr);

  ins_cost(2 * VOLATILE_REF_COST);

  format %{ "cmpxchg $res = $mem, $oldval, $newval" %}

  ins_encode %{
    guarantee($mem$$index == -1 && $mem$$disp == 0, "impossible encoding");
    __ cmpxchg($mem$$Register, $oldval$$Register, $newval$$Register, Assembler::xword,
               false /* acquire */, true /* release */, false /* weak */, $res$$Register);
    if (barrier_data() != ZLoadBarrierElided) {
      Label good;
      __ ldr(rscratch1, Address(rthread, ZThreadLocalData::address_bad_mask_offset()));
      __ andr(rscratch1, rscratch1, $res$$Register);
      __ cbz(rscratch1, good);
      z_load_barrier_slow_path(_masm, this, Address($mem$$Register), $res$$Register /* ref */, rscratch1 /* tmp */);
      __ cmpxchg($mem$$Register, $oldval$$Register, $newval$$Register, Assembler::xword,
                 false /* acquire */, true /* release */, false /* weak */, $res$$Register);
      __ bind(good);
    }
  %}

  ins_pipe(pipe_slow);
%}

instruct zCompareAndExchangePAcq(iRegPNoSp res, indirect mem, iRegP oldval, iRegP newval, rFlagsReg cr) %{
  match(Set res (CompareAndExchangeP mem (Binary oldval newval)));
  predicate(UseZGC && needs_acquiring_load_exclusive(n) && n->as_LoadStore()->barrier_data() == ZLoadBarrierStrong);
  effect(TEMP_DEF res, KILL cr);

  ins_cost(2 * VOLATILE_REF_COST);

  format %{ "cmpxchg $res = $mem, $oldval, $newval" %}

  ins_encode %{
    guarantee($mem$$index == -1 && $mem$$disp == 0, "impossible encoding");
    __ cmpxchg($mem$$Register, $oldval$$Register, $newval$$Register, Assembler::xword,
               true /* acquire */, true /* release */, false /* weak */, $res$$Register);
    if (barrier_data() != ZLoadBarrierElided) {
      Label good;
      __ ldr(rscratch1, Address(rthread, ZThreadLocalData::address_bad_mask_offset()));
      __ andr(rscratch1, rscratch1, $res$$Register);
      __ cbz(rscratch1, good);
      z_load_barrier_slow_path(_masm, this, Address($mem$$Register), $res$$Register /* ref */, rscratch1 /* tmp */);
      __ cmpxchg($mem$$Register, $oldval$$Register, $newval$$Register, Assembler::xword,
                 true /* acquire */, true /* release */, false /* weak */, $res$$Register);
      __ bind(good);
    }
  %}

  ins_pipe(pipe_slow);
%}

instruct zGetAndSetP(indirect mem, iRegP newv, iRegPNoSp prev, rFlagsReg cr) %{
  match(Set prev (GetAndSetP mem newv));
  predicate(UseZGC && !needs_acquiring_load_exclusive(n) && n->as_LoadStore()->barrier_data() != 0);
  effect(TEMP_DEF prev, KILL cr);

  ins_cost(2 * VOLATILE_REF_COST);

  format %{ "atomic_xchg  $prev, $newv, [$mem]" %}

  ins_encode %{
    __ atomic_xchg($prev$$Register, $newv$$Register, $mem$$Register);
    z_load_barrier(_masm, this, Address(noreg, 0), $prev$$Register, rscratch2 /* tmp */, barrier_data());
  %}

  ins_pipe(pipe_serial);
%}

instruct zGetAndSetPAcq(indirect mem, iRegP newv, iRegPNoSp prev, rFlagsReg cr) %{
  match(Set prev (GetAndSetP mem newv));
  predicate(UseZGC && needs_acquiring_load_exclusive(n) && (n->as_LoadStore()->barrier_data() != 0));
  effect(TEMP_DEF prev, KILL cr);

  ins_cost(VOLATILE_REF_COST);

  format %{ "atomic_xchg_acq  $prev, $newv, [$mem]" %}

  ins_encode %{
    __ atomic_xchgal($prev$$Register, $newv$$Register, $mem$$Register);
    z_load_barrier(_masm, this, Address(noreg, 0), $prev$$Register, rscratch2 /* tmp */, barrier_data());
  %}
  ins_pipe(pipe_serial);
%}