1 /* 2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2018, SAP SE. 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 "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 #define TIMES_OOP (UseCompressedOops ? Address::times_4 : Address::times_8) 46 47 void CardTableBarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators, Register addr, Register count, 48 bool do_return) { 49 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(Universe::heap()->barrier_set()); 50 CardTable* ct = ctbs->card_table(); 51 assert(sizeof(*ct->byte_map_base()) == sizeof(jbyte), "adjust this code"); 52 53 NearLabel doXC, done; 54 assert_different_registers(Z_R0, Z_R1, addr, count); 55 56 // Nothing to do if count <= 0. 57 if (!do_return) { 58 __ compare64_and_branch(count, (intptr_t) 0, Assembler::bcondNotHigh, done); 59 } else { 60 __ z_ltgr(count, count); 61 __ z_bcr(Assembler::bcondNotPositive, Z_R14); 62 } 63 64 // Note: We can't combine the shifts. We could lose a carry 65 // from calculating the array end address. 66 // count = (count-1)*BytesPerHeapOop + addr 67 // Count holds addr of last oop in array then. 68 __ z_sllg(count, count, LogBytesPerHeapOop); 69 __ add2reg_with_index(count, -BytesPerHeapOop, count, addr); 70 71 // Get base address of card table. 72 __ load_const_optimized(Z_R1, (address)ct->byte_map_base()); 73 74 // count = (count>>shift) - (addr>>shift) 75 __ z_srlg(addr, addr, CardTable::card_shift); 76 __ z_srlg(count, count, CardTable::card_shift); 77 78 // Prefetch first elements of card table for update. 79 if (VM_Version::has_Prefetch()) { 80 __ z_pfd(0x02, 0, addr, Z_R1); 81 } 82 83 // Special case: clear just one byte. 84 __ clear_reg(Z_R0, true, false); // Used for doOneByte. 85 __ z_sgr(count, addr); // Count = n-1 now, CC used for brc below. 86 __ z_stc(Z_R0, 0, addr, Z_R1); // Must preserve CC from z_sgr. 87 if (!do_return) { 88 __ z_brz(done); 89 } else { 90 __ z_bcr(Assembler::bcondZero, Z_R14); 91 } 92 93 __ z_cghi(count, 255); 94 __ z_brnh(doXC); 95 96 // MVCLE: clear a long area. 97 // Start addr of card table range = base + addr. 98 // # bytes in card table range = (count + 1) 99 __ add2reg_with_index(Z_R0, 0, Z_R1, addr); 100 __ add2reg(Z_R1, 1, count); 101 102 // dirty hack: 103 // There are just two callers. Both pass 104 // count in Z_ARG3 = Z_R4 105 // addr in Z_ARG2 = Z_R3 106 // ==> use Z_ARG2 as src len reg = 0 107 // Z_ARG1 as src addr (ignored) 108 assert(count == Z_ARG3, "count: unexpected register number"); 109 assert(addr == Z_ARG2, "addr: unexpected register number"); 110 __ clear_reg(Z_ARG2, true, false); 111 112 __ MacroAssembler::move_long_ext(Z_R0, Z_ARG1, 0); 113 114 if (!do_return) { 115 __ z_bru(done); 116 } else { 117 __ z_bcr(Assembler::bcondAlways, Z_R14); 118 } 119 120 // XC: clear a short area. 121 Label XC_template; // Instr template, never exec directly! 122 __ bind(XC_template); 123 __ z_xc(0, 0, addr, 0, addr); 124 125 __ bind(doXC); 126 // start addr of card table range = base + addr 127 // end addr of card table range = base + addr + count 128 __ add2reg_with_index(addr, 0, Z_R1, addr); 129 130 if (VM_Version::has_ExecuteExtensions()) { 131 __ z_exrl(count, XC_template); // Execute XC with var. len. 132 } else { 133 __ z_larl(Z_R1, XC_template); 134 __ z_ex(count, 0, Z_R0, Z_R1); // Execute XC with var. len. 135 } 136 if (do_return) { 137 __ z_br(Z_R14); 138 } 139 140 __ bind(done); 141 }