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 "runtime/jniHandles.hpp" 28 29 #define __ masm-> 30 31 void BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 32 Register dst, Address src, Register tmp1, Register tmp_thread) { 33 34 // LR is live. It must be saved around calls. 35 36 bool on_heap = (decorators & IN_HEAP) != 0; 37 bool on_root = (decorators & IN_ROOT) != 0; 38 bool oop_not_null = (decorators & OOP_NOT_NULL) != 0; 39 switch (type) { 40 case T_OBJECT: 41 case T_ARRAY: { 42 if (on_heap) { 43 if (UseCompressedOops) { 44 __ ldrw(dst, src); 45 if (oop_not_null) { 46 __ decode_heap_oop_not_null(dst); 47 } else { 48 __ decode_heap_oop(dst); 49 } 50 } else { 51 __ ldr(dst, src); 52 } 53 } else { 54 assert(on_root, "why else?"); 55 __ ldr(dst, src); 56 } 57 break; 58 } 59 default: Unimplemented(); 60 } 61 } 62 63 void BarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 64 Address dst, Register val, Register tmp1, Register tmp2) { 65 bool on_heap = (decorators & IN_HEAP) != 0; 66 bool on_root = (decorators & IN_ROOT) != 0; 67 switch (type) { 68 case T_OBJECT: 69 case T_ARRAY: { 70 val = val == noreg ? zr : val; 71 if (on_heap) { 72 if (UseCompressedOops) { 73 assert(!dst.uses(val), "not enough registers"); 74 if (val != zr) { 75 __ encode_heap_oop(val); 76 } 77 __ strw(val, dst); 78 } else { 79 __ str(val, dst); 80 } 81 } else { 82 assert(on_root, "why else?"); 83 __ str(val, dst); 84 } 85 break; 86 } 87 default: Unimplemented(); 88 } 89 } 90 91 void BarrierSetAssembler::try_resolve_jobject_in_native(MacroAssembler* masm, Register jni_env, 92 Register obj, Register tmp, Label& slowpath) { 93 // If mask changes we need to ensure that the inverse is still encodable as an immediate 94 STATIC_ASSERT(JNIHandles::weak_tag_mask == 1); 95 __ andr(obj, obj, ~JNIHandles::weak_tag_mask); 96 __ ldr(obj, Address(obj, 0)); // *obj 97 }