1 /* 2 * Copyright (c) 2003, 2020, 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 package sun.jvm.hotspot.debugger.linux.amd64; 26 27 import sun.jvm.hotspot.debugger.*; 28 import sun.jvm.hotspot.debugger.amd64.*; 29 import sun.jvm.hotspot.debugger.linux.*; 30 import sun.jvm.hotspot.debugger.cdbg.*; 31 import sun.jvm.hotspot.debugger.cdbg.basic.*; 32 33 final public class LinuxAMD64CFrame extends BasicCFrame { 34 35 public static LinuxAMD64CFrame getTopFrame(LinuxDebugger dbg, Address rip, ThreadContext context) { 36 Address libptr = dbg.findLibPtrByAddress(rip); 37 Address cfa = context.getRegisterAsAddress(AMD64ThreadContext.RBP); 38 DwarfParser dwarf = null; 39 40 if (libptr != null) { // Native frame 41 try { 42 dwarf = new DwarfParser(libptr); 43 dwarf.processDwarf(rip); 44 cfa = ((dwarf.getCFARegister() == AMD64ThreadContext.RBP) && 45 !dwarf.isBPOffsetAvailable()) 46 ? context.getRegisterAsAddress(AMD64ThreadContext.RBP) 47 : context.getRegisterAsAddress(dwarf.getCFARegister()) 48 .addOffsetTo(dwarf.getCFAOffset()); 49 } catch (DebuggerException e) { 50 // Bail out to Java frame case 51 } 52 } 53 54 return (cfa == null) ? null 55 : new LinuxAMD64CFrame(dbg, cfa, rip, dwarf); 56 } 57 58 private LinuxAMD64CFrame(LinuxDebugger dbg, Address cfa, Address rip, DwarfParser dwarf) { 59 super(dbg.getCDebugger()); 60 this.cfa = cfa; 61 this.rip = rip; 62 this.dbg = dbg; 63 this.dwarf = dwarf; 64 } 65 66 // override base class impl to avoid ELF parsing 67 public ClosestSymbol closestSymbolToPC() { 68 // try native lookup in debugger. 69 return dbg.lookup(dbg.getAddressValue(pc())); 70 } 71 72 public Address pc() { 73 return rip; 74 } 75 76 public Address localVariableBase() { 77 return cfa; 78 } 79 80 private Address getNextPC(boolean useDwarf) { 81 try { 82 long offs = useDwarf ? dwarf.getReturnAddressOffsetFromCFA() 83 : ADDRESS_SIZE; 84 return cfa.getAddressAt(offs); 85 } catch (UnmappedAddressException | UnalignedAddressException e) { 86 return null; 87 } 88 } 89 90 private boolean isValidFrame(Address nextCFA, ThreadContext context) { 91 return (nextCFA != null) && 92 !nextCFA.lessThan(context.getRegisterAsAddress(AMD64ThreadContext.RSP)); 93 } 94 95 private Address getNextCFA(DwarfParser nextDwarf, ThreadContext context) { 96 Address nextCFA; 97 98 if (nextDwarf == null) { // Next frame is Java 99 nextCFA = (dwarf == null) ? cfa.getAddressAt(0) // Current frame is Java (Use RBP) 100 : cfa.getAddressAt(dwarf.getBasePointerOffsetFromCFA()); // Current frame is Native 101 } else { // Next frame is Native 102 if (dwarf == null) { // Current frame is Java (Use RBP) 103 nextCFA = cfa.getAddressAt(0); 104 } else { // Current frame is Native 105 int nextCFAReg = nextDwarf.getCFARegister(); 106 if (!dwarf.isBPOffsetAvailable() && // Use RBP as CFA 107 (nextCFAReg == AMD64ThreadContext.RBP) && 108 (nextCFAReg != dwarf.getCFARegister())) { 109 nextCFA = context.getRegisterAsAddress(AMD64ThreadContext.RBP); 110 if (nextCFA == null) { 111 return null; 112 } 113 nextCFA = nextCFA.getAddressAt(0); 114 } else { 115 nextCFA = cfa.getAddressAt(dwarf.getBasePointerOffsetFromCFA()); 116 } 117 } 118 if (nextCFA != null) { 119 nextCFA = nextCFA.addOffsetTo(-nextDwarf.getBasePointerOffsetFromCFA()); 120 } 121 } 122 123 return isValidFrame(nextCFA, context) ? nextCFA : null; 124 } 125 126 private DwarfParser getNextDwarf(Address nextPC) { 127 DwarfParser nextDwarf = null; 128 129 if ((dwarf != null) && dwarf.isIn(nextPC)) { 130 nextDwarf = dwarf; 131 } else { 132 Address libptr = dbg.findLibPtrByAddress(nextPC); 133 if (libptr != null) { 134 try { 135 nextDwarf = new DwarfParser(libptr); 136 } catch (DebuggerException e) { 137 // Bail out to Java frame 138 } 139 } 140 } 141 142 if (nextDwarf != null) { 143 nextDwarf.processDwarf(nextPC); 144 } 145 146 return nextDwarf; 147 } 148 149 @Override 150 public CFrame sender(ThreadProxy thread) { 151 ThreadContext context = thread.getContext(); 152 153 Address nextPC = getNextPC(dwarf != null); 154 if (nextPC == null) { 155 return null; 156 } 157 158 DwarfParser nextDwarf = getNextDwarf(nextPC); 159 Address nextCFA = getNextCFA(nextDwarf, context); 160 return isValidFrame(nextCFA, context) ? new LinuxAMD64CFrame(dbg, nextCFA, nextPC, nextDwarf) 161 : null; 162 } 163 164 // package/class internals only 165 private static final int ADDRESS_SIZE = 8; 166 private Address rip; 167 private Address cfa; 168 private LinuxDebugger dbg; 169 private DwarfParser dwarf; 170 }