1 2 /* 3 * Copyright (c) 2018, Oracle and/or its affiliates. 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/cardTableModRefBSCodeGen.hpp" 32 #include "gc/shared/collectedHeap.hpp" 33 #include "interpreter/interp_masm.hpp" 34 35 #define __ masm-> 36 37 #ifdef PRODUCT 38 #define BLOCK_COMMENT(str) /* nothing */ 39 #else 40 #define BLOCK_COMMENT(str) __ block_comment(str) 41 #endif 42 43 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":") 44 45 void CardTableModRefBSCodeGen::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators, Register addr, Register count, Register tmp) { 46 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(Universe::heap()->barrier_set()); 47 CardTable* ct = ctbs->card_table(); 48 assert(sizeof(*ct->byte_map_base()) == sizeof(jbyte), "adjust this code"); 49 assert_different_registers(addr, count, tmp); 50 51 Label L_loop, L_done; 52 53 __ cmp_and_br_short(count, 0, Assembler::equal, Assembler::pt, L_done); // zero count - nothing to do 54 55 __ sll_ptr(count, LogBytesPerHeapOop, count); 56 __ sub(count, BytesPerHeapOop, count); 57 __ add(count, addr, count); 58 // Use two shifts to clear out those low order two bits! (Cannot opt. into 1.) 59 __ srl_ptr(addr, CardTable::card_shift, addr); 60 __ srl_ptr(count, CardTable::card_shift, count); 61 __ sub(count, addr, count); 62 AddressLiteral rs(ct->byte_map_base()); 63 __ set(rs, tmp); 64 __ BIND(L_loop); 65 __ stb(G0, tmp, addr); 66 __ subcc(count, 1, count); 67 __ brx(Assembler::greaterEqual, false, Assembler::pt, L_loop); 68 __ delayed()->add(addr, 1, addr); 69 70 __ BIND(L_done); 71 }