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 dwarf = new DwarfParser(libptr);
42 try {
43 dwarf.processDwarf(rip);
44 } catch (DebuggerException e) {
45 // DWARF processing should succeed when the frame is native
46 // but it might fail if Common Information Entry (CIE) has language
47 // personality routine and/or Language Specific Data Area (LSDA).
48 return new LinuxAMD64CFrame(dbg, cfa, rip, dwarf, true);
49 }
50 cfa = ((dwarf.getCFARegister() == AMD64ThreadContext.RBP) &&
51 !dwarf.isBPOffsetAvailable())
52 ? context.getRegisterAsAddress(AMD64ThreadContext.RBP)
53 : context.getRegisterAsAddress(dwarf.getCFARegister())
54 .addOffsetTo(dwarf.getCFAOffset());
55 }
56
57 return (cfa == null) ? null
58 : new LinuxAMD64CFrame(dbg, cfa, rip, dwarf);
59 }
60
61 private LinuxAMD64CFrame(LinuxDebugger dbg, Address cfa, Address rip, DwarfParser dwarf) {
62 this(dbg, cfa, rip, dwarf, false);
63 }
64
65 private LinuxAMD64CFrame(LinuxDebugger dbg, Address cfa, Address rip, DwarfParser dwarf, boolean lastFrame) {
66 super(dbg.getCDebugger());
67 this.cfa = cfa;
68 this.rip = rip;
69 this.dbg = dbg;
70 this.dwarf = dwarf;
71 this.lastFrame = lastFrame;
72 }
73
74 // override base class impl to avoid ELF parsing
75 public ClosestSymbol closestSymbolToPC() {
76 // try native lookup in debugger.
77 return dbg.lookup(dbg.getAddressValue(pc()));
78 }
79
80 public Address pc() {
81 return rip;
82 }
83
84 public Address localVariableBase() {
85 return cfa;
86 }
87
88 private Address getNextPC(boolean useDwarf) {
89 try {
90 long offs = useDwarf ? dwarf.getReturnAddressOffsetFromCFA()
91 : ADDRESS_SIZE;
92 return cfa.getAddressAt(offs);
93 } catch (UnmappedAddressException | UnalignedAddressException e) {
94 return null;
95 }
96 }
97
98 private boolean isValidFrame(Address nextCFA, ThreadContext context) {
99 return (nextCFA != null) &&
100 !nextCFA.lessThan(context.getRegisterAsAddress(AMD64ThreadContext.RSP));
101 }
102
103 private Address getNextCFA(DwarfParser nextDwarf, ThreadContext context) {
104 Address nextCFA;
105
106 if (nextDwarf == null) { // Next frame is Java
107 nextCFA = (dwarf == null) ? cfa.getAddressAt(0) // Current frame is Java (Use RBP)
108 : cfa.getAddressAt(dwarf.getBasePointerOffsetFromCFA()); // Current frame is Native
109 } else { // Next frame is Native
110 if (dwarf == null) { // Current frame is Java (Use RBP)
111 nextCFA = cfa.getAddressAt(0);
112 } else { // Current frame is Native
113 int nextCFAReg = nextDwarf.getCFARegister();
114 if (!dwarf.isBPOffsetAvailable() && // Use RBP as CFA
115 (nextCFAReg == AMD64ThreadContext.RBP) &&
116 (nextCFAReg != dwarf.getCFARegister())) {
117 nextCFA = context.getRegisterAsAddress(AMD64ThreadContext.RBP);
118 if (nextCFA == null) {
119 return null;
120 }
121 nextCFA = nextCFA.getAddressAt(0);
122 } else {
123 nextCFA = cfa.getAddressAt(dwarf.getBasePointerOffsetFromCFA());
124 }
125 }
126 if (nextCFA != null) {
127 nextCFA = nextCFA.addOffsetTo(-nextDwarf.getBasePointerOffsetFromCFA());
128 }
129 }
130
131 return isValidFrame(nextCFA, context) ? nextCFA : null;
132 }
133
134 @Override
135 public CFrame sender(ThreadProxy thread) {
136 if (lastFrame) {
137 return null;
138 }
139
140 ThreadContext context = thread.getContext();
141
142 Address nextPC = getNextPC(dwarf != null);
143 if (nextPC == null) {
144 return null;
145 }
146
147 DwarfParser nextDwarf = null;
148
149 if ((dwarf != null) && dwarf.isIn(nextPC)) {
150 nextDwarf = dwarf;
151 } else {
152 Address libptr = dbg.findLibPtrByAddress(nextPC);
153 if (libptr != null) {
154 try {
155 nextDwarf = new DwarfParser(libptr);
156 } catch (DebuggerException e) {
157 // Bail out to Java frame
158 }
159 }
160 }
161
162 if (nextDwarf != null) {
163 try {
164 nextDwarf.processDwarf(nextPC);
165 } catch (DebuggerException e) {
166 // DWARF processing should succeed when the frame is native
167 // but it might fail if Common Information Entry (CIE) has language
168 // personality routine and/or Language Specific Data Area (LSDA).
169 return new LinuxAMD64CFrame(dbg, null, nextPC, nextDwarf, true);
170 }
171 }
172
173 Address nextCFA = getNextCFA(nextDwarf, context);
174 return isValidFrame(nextCFA, context) ? new LinuxAMD64CFrame(dbg, nextCFA, nextPC, nextDwarf)
175 : null;
176 }
177
178 // package/class internals only
179 private static final int ADDRESS_SIZE = 8;
180 private Address rip;
181 private Address cfa;
182 private LinuxDebugger dbg;
183 private DwarfParser dwarf;
184 private boolean lastFrame;
185 }