1 /* 2 * Copyright (c) 2018, Oracle and/or its affiliates. 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 "asm/macroAssembler.inline.hpp" 27 #include "gc/shared/barrierSet.hpp" 28 #include "gc/shared/cardTable.hpp" 29 #include "gc/shared/cardTableBarrierSet.hpp" 30 #include "gc/shared/cardTableBarrierSetAssembler.hpp" 31 #include "interpreter/interp_masm.hpp" 32 33 #define __ masm-> 34 35 36 void CardTableBarrierSetAssembler::store_check(MacroAssembler* masm, Register obj, Address dst) { 37 38 BarrierSet* bs = BarrierSet::barrier_set(); 39 assert(bs->kind() == BarrierSet::CardTableBarrierSet, "Wrong barrier set kind"); 40 41 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs); 42 CardTable* ct = ctbs->card_table(); 43 assert(sizeof(*ct->byte_map_base()) == sizeof(jbyte), "adjust this code"); 44 45 __ lsr(obj, obj, CardTable::card_shift); 46 47 assert(CardTable::dirty_card_val() == 0, "must be"); 48 49 __ load_byte_map_base(rscratch1); 50 51 if (UseCondCardMark) { 52 Label L_already_dirty; 53 __ membar(Assembler::StoreLoad); 54 __ ldrb(rscratch2, Address(obj, rscratch1)); 55 __ cbz(rscratch2, L_already_dirty); 56 __ strb(zr, Address(obj, rscratch1)); 57 __ bind(L_already_dirty); 58 } else { 59 if (UseConcMarkSweepGC && CMSPrecleaningEnabled) { 60 __ membar(Assembler::StoreStore); 61 } 62 __ strb(zr, Address(obj, rscratch1)); 63 } 64 } 65 66 void CardTableBarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators, 67 Register start, Register end, Register scratch, RegSet saved_regs) { 68 BarrierSet* bs = BarrierSet::barrier_set(); 69 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs); 70 CardTable* ct = ctbs->card_table(); 71 assert(sizeof(*ct->byte_map_base()) == sizeof(jbyte), "adjust this code"); 72 73 Label L_loop; 74 75 __ lsr(start, start, CardTable::card_shift); 76 __ lsr(end, end, CardTable::card_shift); 77 __ sub(end, end, start); // number of bytes to copy 78 79 const Register count = end; // 'end' register contains bytes count now 80 __ load_byte_map_base(scratch); 81 __ add(start, start, scratch); 82 if (UseConcMarkSweepGC) { 83 __ membar(__ StoreStore); 84 } 85 __ bind(L_loop); 86 __ strb(zr, Address(start, count)); 87 __ subs(count, count, 1); 88 __ br(Assembler::GE, L_loop); 89 } 90 91 void CardTableBarrierSetAssembler::oop_store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 92 Address dst, Register val, Register tmp1, Register tmp2) { 93 bool on_array = (decorators & IN_HEAP_ARRAY) != 0; 94 bool on_anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0; 95 bool precise = on_array || on_anonymous; 96 if (val == noreg) { 97 __ store_heap_oop_null(dst); 98 } else { 99 __ store_heap_oop(dst, val); 100 // flatten object address if needed 101 if (!precise || (dst.index() == noreg && dst.offset() == 0)) { 102 store_check(masm, dst.base(), dst); 103 } else { 104 __ lea(r3, dst); 105 store_check(masm, r3, dst); 106 } 107 } 108 }