1 /* 2 * Copyright (c) 2018, 2019, 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 void CardTableBarrierSetAssembler::store_check(MacroAssembler* masm, Register obj, Address dst) { 36 37 BarrierSet* bs = BarrierSet::barrier_set(); 38 assert(bs->kind() == BarrierSet::CardTableBarrierSet, "Wrong barrier set kind"); 39 40 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs); 41 CardTable* ct = ctbs->card_table(); 42 43 __ lsr(obj, obj, CardTable::card_shift); 44 45 assert(CardTable::dirty_card_val() == 0, "must be"); 46 47 __ load_byte_map_base(rscratch1); 48 49 if (UseCondCardMark) { 50 Label L_already_dirty; 51 __ membar(Assembler::StoreLoad); 52 __ ldrb(rscratch2, Address(obj, rscratch1)); 53 __ cbz(rscratch2, L_already_dirty); 54 __ strb(zr, Address(obj, rscratch1)); 55 __ bind(L_already_dirty); 56 } else { 57 if (ct->scanned_concurrently()) { 58 __ membar(Assembler::StoreStore); 59 } 60 __ strb(zr, Address(obj, rscratch1)); 61 } 62 } 63 64 void CardTableBarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators, 65 Register start, Register count, Register scratch, RegSet saved_regs) { 66 BarrierSet* bs = BarrierSet::barrier_set(); 67 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs); 68 CardTable* ct = ctbs->card_table(); 69 70 Label L_loop, L_done; 71 const Register end = count; 72 73 __ cbz(count, L_done); // zero count - nothing to do 74 75 __ lea(end, Address(start, count, Address::lsl(LogBytesPerHeapOop))); // end = start + count << LogBytesPerHeapOop 76 __ sub(end, end, BytesPerHeapOop); // last element address to make inclusive 77 __ lsr(start, start, CardTable::card_shift); 78 __ lsr(end, end, CardTable::card_shift); 79 __ sub(count, end, start); // number of bytes to copy 80 81 __ load_byte_map_base(scratch); 82 __ add(start, start, scratch); 83 if (ct->scanned_concurrently()) { 84 __ membar(__ StoreStore); 85 } 86 __ bind(L_loop); 87 __ strb(zr, Address(start, count)); 88 __ subs(count, count, 1); 89 __ br(Assembler::GE, L_loop); 90 __ bind(L_done); 91 } 92 93 void CardTableBarrierSetAssembler::oop_store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 94 Address dst, Register val, Register tmp1, Register tmp2, Register tmp3) { 95 bool in_heap = (decorators & IN_HEAP) != 0; 96 bool is_array = (decorators & IS_ARRAY) != 0; 97 bool on_anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0; 98 bool precise = is_array || on_anonymous; 99 100 bool needs_post_barrier = val != noreg && in_heap; 101 BarrierSetAssembler::store_at(masm, decorators, type, dst, val, noreg, noreg, noreg); 102 if (needs_post_barrier) { 103 // flatten object address if needed 104 if (!precise || (dst.index() == noreg && dst.offset() == 0)) { 105 if (tmp3 != noreg) { 106 // Called by MacroAssembler::pack_value_helper. We cannot corrupt the dst.base() register 107 __ mov(tmp3, dst.base()); 108 store_check(masm, tmp3, dst); 109 } else { 110 // It's OK to corrupt the dst.base() register. 111 store_check(masm, dst.base(), dst); 112 } 113 114 } else { 115 __ lea(r3, dst); 116 store_check(masm, r3, dst); 117 } 118 } 119 }