1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <stdint.h>
18 #include <string.h>
19
20 #include <functional>
21
22 #include <unwindstack/Elf.h>
23 #include <unwindstack/MachineArm64.h>
24 #include <unwindstack/MapInfo.h>
25 #include <unwindstack/Memory.h>
26 #include <unwindstack/RegsArm64.h>
27 #include <unwindstack/UcontextArm64.h>
28 #include <unwindstack/UserArm64.h>
29
30 namespace unwindstack {
31
RegsArm64()32 RegsArm64::RegsArm64()
33 : RegsImpl<uint64_t>(ARM64_REG_LAST, Location(LOCATION_REGISTER, ARM64_REG_LR)) {}
34
Arch()35 ArchEnum RegsArm64::Arch() {
36 return ARCH_ARM64;
37 }
38
pc()39 uint64_t RegsArm64::pc() {
40 return regs_[ARM64_REG_PC];
41 }
42
sp()43 uint64_t RegsArm64::sp() {
44 return regs_[ARM64_REG_SP];
45 }
46
set_pc(uint64_t pc)47 void RegsArm64::set_pc(uint64_t pc) {
48 regs_[ARM64_REG_PC] = pc;
49 }
50
set_sp(uint64_t sp)51 void RegsArm64::set_sp(uint64_t sp) {
52 regs_[ARM64_REG_SP] = sp;
53 }
54
GetPcAdjustment(uint64_t rel_pc,Elf *)55 uint64_t RegsArm64::GetPcAdjustment(uint64_t rel_pc, Elf*) {
56 if (rel_pc < 4) {
57 return 0;
58 }
59 return 4;
60 }
61
SetPcFromReturnAddress(Memory *)62 bool RegsArm64::SetPcFromReturnAddress(Memory*) {
63 uint64_t lr = regs_[ARM64_REG_LR];
64 if (regs_[ARM64_REG_PC] == lr) {
65 return false;
66 }
67
68 regs_[ARM64_REG_PC] = lr;
69 return true;
70 }
71
IterateRegisters(std::function<void (const char *,uint64_t)> fn)72 void RegsArm64::IterateRegisters(std::function<void(const char*, uint64_t)> fn) {
73 fn("x0", regs_[ARM64_REG_R0]);
74 fn("x1", regs_[ARM64_REG_R1]);
75 fn("x2", regs_[ARM64_REG_R2]);
76 fn("x3", regs_[ARM64_REG_R3]);
77 fn("x4", regs_[ARM64_REG_R4]);
78 fn("x5", regs_[ARM64_REG_R5]);
79 fn("x6", regs_[ARM64_REG_R6]);
80 fn("x7", regs_[ARM64_REG_R7]);
81 fn("x8", regs_[ARM64_REG_R8]);
82 fn("x9", regs_[ARM64_REG_R9]);
83 fn("x10", regs_[ARM64_REG_R10]);
84 fn("x11", regs_[ARM64_REG_R11]);
85 fn("x12", regs_[ARM64_REG_R12]);
86 fn("x13", regs_[ARM64_REG_R13]);
87 fn("x14", regs_[ARM64_REG_R14]);
88 fn("x15", regs_[ARM64_REG_R15]);
89 fn("x16", regs_[ARM64_REG_R16]);
90 fn("x17", regs_[ARM64_REG_R17]);
91 fn("x18", regs_[ARM64_REG_R18]);
92 fn("x19", regs_[ARM64_REG_R19]);
93 fn("x20", regs_[ARM64_REG_R20]);
94 fn("x21", regs_[ARM64_REG_R21]);
95 fn("x22", regs_[ARM64_REG_R22]);
96 fn("x23", regs_[ARM64_REG_R23]);
97 fn("x24", regs_[ARM64_REG_R24]);
98 fn("x25", regs_[ARM64_REG_R25]);
99 fn("x26", regs_[ARM64_REG_R26]);
100 fn("x27", regs_[ARM64_REG_R27]);
101 fn("x28", regs_[ARM64_REG_R28]);
102 fn("x29", regs_[ARM64_REG_R29]);
103 fn("sp", regs_[ARM64_REG_SP]);
104 fn("lr", regs_[ARM64_REG_LR]);
105 fn("pc", regs_[ARM64_REG_PC]);
106 }
107
Read(void * remote_data)108 Regs* RegsArm64::Read(void* remote_data) {
109 arm64_user_regs* user = reinterpret_cast<arm64_user_regs*>(remote_data);
110
111 RegsArm64* regs = new RegsArm64();
112 memcpy(regs->RawData(), &user->regs[0], (ARM64_REG_R31 + 1) * sizeof(uint64_t));
113 uint64_t* reg_data = reinterpret_cast<uint64_t*>(regs->RawData());
114 reg_data[ARM64_REG_PC] = user->pc;
115 reg_data[ARM64_REG_SP] = user->sp;
116 return regs;
117 }
118
CreateFromUcontext(void * ucontext)119 Regs* RegsArm64::CreateFromUcontext(void* ucontext) {
120 arm64_ucontext_t* arm64_ucontext = reinterpret_cast<arm64_ucontext_t*>(ucontext);
121
122 RegsArm64* regs = new RegsArm64();
123 memcpy(regs->RawData(), &arm64_ucontext->uc_mcontext.regs[0], ARM64_REG_LAST * sizeof(uint64_t));
124 return regs;
125 }
126
StepIfSignalHandler(uint64_t rel_pc,Elf * elf,Memory * process_memory)127 bool RegsArm64::StepIfSignalHandler(uint64_t rel_pc, Elf* elf, Memory* process_memory) {
128 uint64_t data;
129 Memory* elf_memory = elf->memory();
130 // Read from elf memory since it is usually more expensive to read from
131 // process memory.
132 if (!elf_memory->ReadFully(rel_pc, &data, sizeof(data))) {
133 return false;
134 }
135
136 // Look for the kernel sigreturn function.
137 // __kernel_rt_sigreturn:
138 // 0xd2801168 mov x8, #0x8b
139 // 0xd4000001 svc #0x0
140 if (data != 0xd4000001d2801168ULL) {
141 return false;
142 }
143
144 // SP + sizeof(siginfo_t) + uc_mcontext offset + X0 offset.
145 if (!process_memory->ReadFully(regs_[ARM64_REG_SP] + 0x80 + 0xb0 + 0x08, regs_.data(),
146 sizeof(uint64_t) * ARM64_REG_LAST)) {
147 return false;
148 }
149 return true;
150 }
151
Clone()152 Regs* RegsArm64::Clone() {
153 return new RegsArm64(*this);
154 }
155
156 } // namespace unwindstack
157