1 /*

     2  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

     3  * Copyright (c) 2018, SAP SE. All rights reserved.

     4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     5  *

     6  * This code is free software; you can redistribute it and/or modify it

     7  * under the terms of the GNU General Public License version 2 only, as

     8  * published by the Free Software Foundation.

     9  *

    10  * This code is distributed in the hope that it will be useful, but WITHOUT

    11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    13  * version 2 for more details (a copy is included in the LICENSE file that

    14  * accompanied this code).

    15  *

    16  * You should have received a copy of the GNU General Public License version

    17  * 2 along with this work; if not, write to the Free Software Foundation,

    18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    19  *

    20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    21  * or visit www.oracle.com if you need additional information or have any

    22  * questions.

    23  *

    24  */

    25 

    26 #include "precompiled.hpp"

    27 #include "gc/shared/barrierSetAssembler.hpp"

    28 #include "interpreter/interp_masm.hpp"

    29 

    30 #define __ masm->

    31 

    32 void BarrierSetAssembler::arraycopy_epilogue(MacroAssembler* masm, DecoratorSet decorators, BasicType type,

    33                                              Register dst, Register count, bool do_return) {

    34   if (do_return) { __ z_br(Z_R14); }

    35 }

    36 

    37 void BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,

    38                                   const Address& addr, Register dst, Register tmp1, Register tmp2, Label *is_null) {

    39   bool on_heap = (decorators & IN_HEAP) != 0;

    40   bool on_root = (decorators & IN_ROOT) != 0;

    41   assert(on_heap || on_root, "where?");

    42 

    43   switch (type) {

    44   case T_ARRAY:

    45   case T_OBJECT: {

    46     if (UseCompressedOops && on_heap) {

    47       __ z_llgf(dst, addr);

    48       if (is_null) {

    49         __ compareU32_and_branch(dst, (intptr_t)0, Assembler::bcondEqual, *is_null);

    50         __ oop_decoder(dst, dst, false);

    51       } else {

    52         __ oop_decoder(dst, dst, true);

    53       }

    54     } else {

    55       __ z_lg(dst, addr);

    56       if (is_null) {

    57         __ compareU64_and_branch(dst, (intptr_t)0, Assembler::bcondEqual, *is_null);

    58       }

    59     }

    60     break;

    61   }

    62   default: Unimplemented();

    63   }

    64 }

    65 

    66 void BarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,

    67                                    const Address& addr, Register val, Register tmp1, Register tmp2, Register tmp3) {

    68   bool on_heap  = (decorators & IN_HEAP) != 0;

    69   bool on_root  = (decorators & IN_ROOT) != 0;

    70   bool not_null = (decorators & OOP_NOT_NULL) != 0;

    71   assert(on_heap || on_root, "where?");

    72   assert_different_registers(val, tmp1, tmp2);

    73 

    74   switch (type) {

    75   case T_ARRAY:

    76   case T_OBJECT: {

    77     if (UseCompressedOops && on_heap) {

    78       if (val == noreg) {

    79         __ clear_mem(addr, 4);

    80       } else if (Universe::narrow_oop_mode() == Universe::UnscaledNarrowOop) {

    81         __ z_st(val, addr);

    82       } else {

    83         Register tmp = (tmp1 != Z_R1) ? tmp1 : tmp2; // Avoid tmp == Z_R1 (see oop_encoder).

    84         __ oop_encoder(tmp, val, !not_null);

    85         __ z_st(tmp, addr);

    86       }

    87     } else {

    88       if (val == noreg) {

    89         __ clear_mem(addr, 8);

    90       } else {

    91         __ z_stg(val, addr);

    92       }

    93     }

    94     break;

    95   }

    96   default: Unimplemented();

    97   }

    98 }

    99 

   100 void BarrierSetAssembler::resolve_jobject(MacroAssembler* masm, Register value, Register tmp1, Register tmp2) {

   101   NearLabel Ldone;

   102   __ z_ltgr(tmp1, value);

   103   __ z_bre(Ldone);          // Use NULL result as-is.

   104 

   105   __ z_nill(value, ~JNIHandles::weak_tag_mask);

   106   __ z_lg(value, 0, value); // Resolve (untagged) jobject.

   107 

   108   __ verify_oop(value);

   109   __ bind(Ldone);

   110 }