1 /* 2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2015-2018, Azul Systems, Inc. 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 "asm/macroAssembler.inline.hpp" 28 #include "gc/shared/barrierSet.hpp" 29 #include "gc/shared/cardTable.hpp" 30 #include "gc/shared/cardTableBarrierSet.hpp" 31 #include "gc/shared/cardTableBarrierSetAssembler.hpp" 32 #include "interpreter/interp_masm.hpp" 33 34 #define __ masm-> 35 36 void CardTableBarrierSetAssembler::store_check(MacroAssembler* masm, Register obj, Address dst) { 37 38 // Does a store check for the oop in register obj. The content of 39 // register obj is destroyed afterwards. 40 41 BarrierSet* bs = BarrierSet::barrier_set(); 42 assert(bs->kind() == BarrierSet::CardTableBarrierSet, 43 "Wrong barrier set kind"); 44 45 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs); 46 CardTable* ct = ctbs->card_table(); 47 assert(sizeof(*ct->byte_map_base()) == sizeof(jbyte), "adjust this code"); 48 49 assert(CardTable::dirty_card_val() == 0, "must be"); 50 51 jbyte *byte_map_base = 52 ((CardTableBarrierSet*)(BarrierSet::barrier_set()))->card_table()->byte_map_base(); 53 __ mov(rscratch1, (uint32_t)byte_map_base); 54 assert((p2i(byte_map_base) & 0xff) == 0, "fix store char 0 below"); 55 56 if (UseCondCardMark) { 57 __ membar(Assembler::StoreLoad); 58 __ ldrb(rscratch2, Address(rscratch1, obj, lsr((int) CardTable::card_shift))); 59 __ cmp(rscratch2, 0); 60 __ strb(rscratch1, Address(rscratch1, obj, lsr((int) CardTable::card_shift)), Assembler::NE); 61 } else { 62 if (ct->scanned_concurrently()) { 63 __ membar(Assembler::StoreStore); 64 } 65 __ strb(rscratch1, Address(rscratch1, obj, lsr((int) CardTable::card_shift))); 66 } 67 } 68 69 void CardTableBarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators, 70 Register start, Register end, Register scratch) { 71 BarrierSet* bs = BarrierSet::barrier_set(); 72 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs); 73 CardTable* ct = ctbs->card_table(); 74 assert(sizeof(*ct->byte_map_base()) == sizeof(jbyte), "adjust this code"); 75 76 Label L_loop; 77 78 __ lsr(start, start, CardTable::card_shift); 79 __ lsr(end, end, CardTable::card_shift); 80 __ sub(end, end, start); // number of bytes to copy 81 82 const Register count = end; // 'end' register contains bytes count now 83 __ mov(scratch, (address)ct->byte_map_base()); 84 __ add(start, start, scratch); 85 if (ct->scanned_concurrently()) { 86 __ membar(__ StoreStore); 87 } 88 __ bind(L_loop); 89 __ mov(scratch, 0); 90 __ strb(scratch, Address(start, count)); 91 __ subs(count, count, 1); 92 __ b(L_loop, Assembler::HS); 93 } 94 95 void CardTableBarrierSetAssembler::oop_store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 96 Address dst, Register val, Register tmp1, Register tmp2) { 97 bool in_heap = (decorators & IN_HEAP) != 0; 98 bool is_array = (decorators & IS_ARRAY) != 0; 99 bool on_anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0; 100 bool precise = is_array || on_anonymous; 101 102 bool needs_post_barrier = val != noreg && in_heap; 103 BarrierSetAssembler::store_word_at(masm, decorators, type, dst, val, tmp1, noreg); 104 if (needs_post_barrier) { 105 // flatten object address if needed 106 if (!precise || (dst.index() == noreg && dst.offset() == 0)) { 107 store_check(masm, dst.base(), dst); 108 } else { 109 __ lea(tmp1, dst); 110 store_check(masm, tmp1, dst); 111 } 112 } 113 }