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 "gc/shared/barrierSetAssembler.hpp" 27 #include "gc/shared/collectedHeap.hpp" 28 #include "memory/universe.hpp" 29 #include "runtime/jniHandles.hpp" 30 #include "runtime/thread.hpp" 31 32 #define __ masm-> 33 34 void BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 35 Register dst, Address src, Register tmp1, Register tmp_thread) { 36 37 // LR is live. It must be saved around calls. 38 39 bool in_heap = (decorators & IN_HEAP) != 0; 40 bool in_native = (decorators & IN_NATIVE) != 0; 41 bool is_not_null = (decorators & IS_NOT_NULL) != 0; 42 switch (type) { 43 case T_OBJECT: 44 case T_ARRAY: { 45 if (in_heap) { 46 if (UseCompressedOops) { 47 __ ldrw(dst, src); 48 if (is_not_null) { 49 __ decode_heap_oop_not_null(dst); 50 } else { 51 __ decode_heap_oop(dst); 52 } 53 } else { 54 __ ldr(dst, src); 55 } 56 } else { 57 assert(in_native, "why else?"); 58 __ ldr(dst, src); 59 } 60 break; 61 } 62 case T_BOOLEAN: __ load_unsigned_byte (dst, src); break; 63 case T_BYTE: __ load_signed_byte (dst, src); break; 64 case T_CHAR: __ load_unsigned_short(dst, src); break; 65 case T_SHORT: __ load_signed_short (dst, src); break; 66 case T_INT: __ ldrw (dst, src); break; 67 case T_LONG: __ ldr (dst, src); break; 68 case T_ADDRESS: __ ldr (dst, src); break; 69 case T_FLOAT: __ ldrs (v0, src); break; 70 case T_DOUBLE: __ ldrd (v0, src); break; 71 default: Unimplemented(); 72 } 73 } 74 75 void BarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 76 Address dst, Register val, Register tmp1, Register tmp2) { 77 bool in_heap = (decorators & IN_HEAP) != 0; 78 bool in_native = (decorators & IN_NATIVE) != 0; 79 switch (type) { 80 case T_OBJECT: 81 case T_ARRAY: { 82 val = val == noreg ? zr : val; 83 if (in_heap) { 84 if (UseCompressedOops) { 85 assert(!dst.uses(val), "not enough registers"); 86 if (val != zr) { 87 __ encode_heap_oop(val); 88 } 89 __ strw(val, dst); 90 } else { 91 __ str(val, dst); 92 } 93 } else { 94 assert(in_native, "why else?"); 95 __ str(val, dst); 96 } 97 break; 98 } 99 case T_BOOLEAN: 100 __ andw(val, val, 0x1); // boolean is true if LSB is 1 101 __ strb(val, dst); 102 break; 103 case T_BYTE: __ strb(val, dst); break; 104 case T_CHAR: __ strh(val, dst); break; 105 case T_SHORT: __ strh(val, dst); break; 106 case T_INT: __ strw(val, dst); break; 107 case T_LONG: __ str (val, dst); break; 108 case T_ADDRESS: __ str (val, dst); break; 109 case T_FLOAT: __ strs(v0, dst); break; 110 case T_DOUBLE: __ strd(v0, dst); break; 111 default: Unimplemented(); 112 } 113 } 114 115 void BarrierSetAssembler::obj_equals(MacroAssembler* masm, 116 Register obj1, Register obj2) { 117 __ cmp(obj1, obj2); 118 } 119 120 void BarrierSetAssembler::try_resolve_jobject_in_native(MacroAssembler* masm, Register jni_env, 121 Register obj, Register tmp, Label& slowpath) { 122 // If mask changes we need to ensure that the inverse is still encodable as an immediate 123 STATIC_ASSERT(JNIHandles::weak_tag_mask == 1); 124 __ andr(obj, obj, ~JNIHandles::weak_tag_mask); 125 __ ldr(obj, Address(obj, 0)); // *obj 126 } 127 128 // Defines obj, preserves var_size_in_bytes, okay for t2 == var_size_in_bytes. 129 void BarrierSetAssembler::tlab_allocate(MacroAssembler* masm, Register obj, 130 Register var_size_in_bytes, 131 int con_size_in_bytes, 132 Register t1, 133 Register t2, 134 Label& slow_case) { 135 assert_different_registers(obj, t2); 136 assert_different_registers(obj, var_size_in_bytes); 137 Register end = t2; 138 139 // verify_tlab(); 140 141 __ ldr(obj, Address(rthread, JavaThread::tlab_top_offset())); 142 if (var_size_in_bytes == noreg) { 143 __ lea(end, Address(obj, con_size_in_bytes)); 144 } else { 145 __ lea(end, Address(obj, var_size_in_bytes)); 146 } 147 __ ldr(rscratch1, Address(rthread, JavaThread::tlab_end_offset())); 148 __ cmp(end, rscratch1); 149 __ br(Assembler::HI, slow_case); 150 151 // update the tlab top pointer 152 __ str(end, Address(rthread, JavaThread::tlab_top_offset())); 153 154 // recover var_size_in_bytes if necessary 155 if (var_size_in_bytes == end) { 156 __ sub(var_size_in_bytes, var_size_in_bytes, obj); 157 } 158 // verify_tlab(); 159 } 160 161 // Defines obj, preserves var_size_in_bytes 162 void BarrierSetAssembler::eden_allocate(MacroAssembler* masm, Register obj, 163 Register var_size_in_bytes, 164 int con_size_in_bytes, 165 Register t1, 166 Label& slow_case) { 167 assert_different_registers(obj, var_size_in_bytes, t1); 168 if (!Universe::heap()->supports_inline_contig_alloc()) { 169 __ b(slow_case); 170 } else { 171 Register end = t1; 172 Register heap_end = rscratch2; 173 Label retry; 174 __ bind(retry); 175 { 176 unsigned long offset; 177 __ adrp(rscratch1, ExternalAddress((address) Universe::heap()->end_addr()), offset); 178 __ ldr(heap_end, Address(rscratch1, offset)); 179 } 180 181 ExternalAddress heap_top((address) Universe::heap()->top_addr()); 182 183 // Get the current top of the heap 184 { 185 unsigned long offset; 186 __ adrp(rscratch1, heap_top, offset); 187 // Use add() here after ARDP, rather than lea(). 188 // lea() does not generate anything if its offset is zero. 189 // However, relocs expect to find either an ADD or a load/store 190 // insn after an ADRP. add() always generates an ADD insn, even 191 // for add(Rn, Rn, 0). 192 __ add(rscratch1, rscratch1, offset); 193 __ ldaxr(obj, rscratch1); 194 } 195 196 // Adjust it my the size of our new object 197 if (var_size_in_bytes == noreg) { 198 __ lea(end, Address(obj, con_size_in_bytes)); 199 } else { 200 __ lea(end, Address(obj, var_size_in_bytes)); 201 } 202 203 // if end < obj then we wrapped around high memory 204 __ cmp(end, obj); 205 __ br(Assembler::LO, slow_case); 206 207 __ cmp(end, heap_end); 208 __ br(Assembler::HI, slow_case); 209 210 // If heap_top hasn't been changed by some other thread, update it. 211 __ stlxr(rscratch2, end, rscratch1); 212 __ cbnzw(rscratch2, retry); 213 214 incr_allocated_bytes(masm, var_size_in_bytes, con_size_in_bytes, t1); 215 } 216 } 217 218 void BarrierSetAssembler::incr_allocated_bytes(MacroAssembler* masm, 219 Register var_size_in_bytes, 220 int con_size_in_bytes, 221 Register t1) { 222 assert(t1->is_valid(), "need temp reg"); 223 224 __ ldr(t1, Address(rthread, in_bytes(JavaThread::allocated_bytes_offset()))); 225 if (var_size_in_bytes->is_valid()) { 226 __ add(t1, t1, var_size_in_bytes); 227 } else { 228 __ add(t1, t1, con_size_in_bytes); 229 } 230 __ str(t1, Address(rthread, in_bytes(JavaThread::allocated_bytes_offset()))); 231 }