1 /*
   2  * Copyright (c) 2018, 2019, Red Hat, Inc. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "c1/c1_LIRAssembler.hpp"
  27 #include "c1/c1_MacroAssembler.hpp"
  28 #include "gc/shenandoah/shenandoahBarrierSet.hpp"
  29 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
  30 #include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
  31 
  32 #define __ masm->masm()->
  33 
  34 void LIR_OpShenandoahCompareAndSwap::emit_code(LIR_Assembler* masm) {
  35   Register addr = _addr->as_register_lo();
  36   Register newval = _new_value->as_register();
  37   Register cmpval = _cmp_value->as_register();
  38   Register tmp1 = _tmp1->as_register();
  39   Register tmp2 = _tmp2->as_register();
  40   Register result = result_opr()->as_register();
  41 
  42   ShenandoahBarrierSet::assembler()->storeval_barrier(masm->masm(), newval, rscratch2);
  43 
  44   if (UseCompressedOops) {
  45     __ encode_heap_oop(tmp1, cmpval);
  46     cmpval = tmp1;
  47     __ encode_heap_oop(tmp2, newval);
  48     newval = tmp2;
  49   }
  50 
  51   ShenandoahBarrierSet::assembler()->cmpxchg_oop(masm->masm(), addr, cmpval, newval, /*acquire*/ false, /*release*/ true, /*weak*/ false, /*is_cae*/ false, result);
  52 }
  53 
  54 #undef __
  55 
  56 #ifdef ASSERT
  57 #define __ gen->lir(__FILE__, __LINE__)->
  58 #else
  59 #define __ gen->lir()->
  60 #endif
  61 
  62 LIR_Opr ShenandoahBarrierSetC1::atomic_cmpxchg_at_resolved(LIRAccess& access, LIRItem& cmp_value, LIRItem& new_value) {
  63   BasicType bt = access.type();
  64   if (access.is_oop()) {
  65     LIRGenerator *gen = access.gen();
  66     if (ShenandoahSATBBarrier) {
  67       pre_barrier(gen, access.access_emit_info(), access.decorators(), access.resolved_addr(),
  68                   LIR_OprFact::illegalOpr /* pre_val */);
  69     }
  70     if (ShenandoahCASBarrier) {
  71       cmp_value.load_item();
  72       new_value.load_item();
  73 
  74       LIR_Opr t1 = gen->new_register(T_OBJECT);
  75       LIR_Opr t2 = gen->new_register(T_OBJECT);
  76       LIR_Opr addr = access.resolved_addr()->as_address_ptr()->base();
  77       LIR_Opr result = gen->new_register(T_INT);
  78 
  79       __ append(new LIR_OpShenandoahCompareAndSwap(addr, cmp_value.result(), new_value.result(), t1, t2, result));
  80       return result;
  81     }
  82   }
  83   return BarrierSetC1::atomic_cmpxchg_at_resolved(access, cmp_value, new_value);
  84 }
  85 
  86 LIR_Opr ShenandoahBarrierSetC1::atomic_xchg_at_resolved(LIRAccess& access, LIRItem& value) {
  87   LIRGenerator* gen = access.gen();
  88   BasicType type = access.type();
  89 
  90   LIR_Opr result = gen->new_register(type);
  91   value.load_item();
  92   LIR_Opr value_opr = value.result();
  93 
  94   if (access.is_oop()) {
  95     value_opr = storeval_barrier(access.gen(), value_opr, access.access_emit_info(), access.decorators());
  96   }
  97 
  98   assert(type == T_INT || is_reference_type(type) LP64_ONLY( || type == T_LONG ), "unexpected type");
  99   LIR_Opr tmp = gen->new_register(T_INT);
 100   __ xchg(access.resolved_addr(), value_opr, result, tmp);
 101 
 102   if (access.is_oop()) {
 103     result = load_reference_barrier(access.gen(), result, LIR_OprFact::addressConst(0), false);
 104     LIR_Opr tmp = gen->new_register(type);
 105     __ move(result, tmp);
 106     result = tmp;
 107     if (ShenandoahSATBBarrier) {
 108       pre_barrier(access.gen(), access.access_emit_info(), access.decorators(), LIR_OprFact::illegalOpr,
 109                   result /* pre_val */);
 110     }
 111   }
 112 
 113   return result;
 114 }