1 /* 2 * Copyright (c) 2018, 2021, 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/shared/gc_globals.hpp" 29 #include "gc/shenandoah/shenandoahBarrierSet.hpp" 30 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp" 31 #include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp" 32 33 #define __ masm->masm()-> 34 35 void LIR_OpShenandoahCompareAndSwap::emit_code(LIR_Assembler* masm) { 36 Register addr = _addr->as_register_lo(); 37 Register newval = _new_value->as_register(); 38 Register cmpval = _cmp_value->as_register(); 39 Register tmp1 = _tmp1->as_register(); 40 Register tmp2 = _tmp2->as_register(); 41 Register result = result_opr()->as_register(); 42 43 ShenandoahBarrierSet::assembler()->iu_barrier(masm->masm(), newval, rscratch2); 44 45 if (UseCompressedOops) { 46 __ encode_heap_oop(tmp1, cmpval); 47 cmpval = tmp1; 48 __ encode_heap_oop(tmp2, newval); 49 newval = tmp2; 50 } 51 52 ShenandoahBarrierSet::assembler()->cmpxchg_oop(masm->masm(), addr, cmpval, newval, /*acquire*/ true, /*release*/ true, /*is_cae*/ false, result); 53 54 if (CompilerConfig::is_c1_only_no_jvmci()) { 55 // The membar here is necessary to prevent reordering between the 56 // release store in the CAS above and a subsequent volatile load. 57 // However for tiered compilation C1 inserts a full barrier before 58 // volatile loads which means we don't need an additional barrier 59 // here (see LIRGenerator::volatile_field_load()). 60 __ membar(__ AnyAny); 61 } 62 } 63 64 #undef __ 65 66 #ifdef ASSERT 67 #define __ gen->lir(__FILE__, __LINE__)-> 68 #else 69 #define __ gen->lir()-> 70 #endif 71 72 LIR_Opr ShenandoahBarrierSetC1::atomic_cmpxchg_at_resolved(LIRAccess& access, LIRItem& cmp_value, LIRItem& new_value) { 73 BasicType bt = access.type(); 74 if (access.is_oop()) { 75 LIRGenerator *gen = access.gen(); 76 if (ShenandoahSATBBarrier) { 77 pre_barrier(gen, access.access_emit_info(), access.decorators(), access.resolved_addr(), 78 LIR_OprFact::illegalOpr /* pre_val */); 79 } 80 if (ShenandoahCASBarrier) { 81 cmp_value.load_item(); 82 new_value.load_item(); 83 84 LIR_Opr t1 = gen->new_register(T_OBJECT); 85 LIR_Opr t2 = gen->new_register(T_OBJECT); 86 LIR_Opr addr = access.resolved_addr()->as_address_ptr()->base(); 87 LIR_Opr result = gen->new_register(T_INT); 88 89 __ append(new LIR_OpShenandoahCompareAndSwap(addr, cmp_value.result(), new_value.result(), t1, t2, result)); 90 return result; 91 } 92 } 93 return BarrierSetC1::atomic_cmpxchg_at_resolved(access, cmp_value, new_value); 94 } 95 96 LIR_Opr ShenandoahBarrierSetC1::atomic_xchg_at_resolved(LIRAccess& access, LIRItem& value) { 97 LIRGenerator* gen = access.gen(); 98 BasicType type = access.type(); 99 100 LIR_Opr result = gen->new_register(type); 101 value.load_item(); 102 LIR_Opr value_opr = value.result(); 103 104 if (access.is_oop()) { 105 value_opr = iu_barrier(access.gen(), value_opr, access.access_emit_info(), access.decorators()); 106 } 107 108 assert(type == T_INT || is_reference_type(type) LP64_ONLY( || type == T_LONG ), "unexpected type"); 109 LIR_Opr tmp = gen->new_register(T_INT); 110 __ xchg(access.resolved_addr(), value_opr, result, tmp); 111 112 if (access.is_oop()) { 113 result = load_reference_barrier(access.gen(), result, LIR_OprFact::addressConst(0), access.decorators()); 114 LIR_Opr tmp = gen->new_register(type); 115 __ move(result, tmp); 116 result = tmp; 117 if (ShenandoahSATBBarrier) { 118 pre_barrier(access.gen(), access.access_emit_info(), access.decorators(), LIR_OprFact::illegalOpr, 119 result /* pre_val */); 120 } 121 } 122 123 return result; 124 }