1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
# Copyright 2022 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
import logging
import os
import re
import subprocess
_CHROME_SRC = os.path.join(os.path.dirname(__file__), os.pardir, os.pardir)
_LLVM_OBJDUMP_PATH = os.path.join(_CHROME_SRC, 'third_party', 'llvm-build',
'Release+Asserts', 'bin', 'llvm-objdump')
# Function lines look like:
# 000177b0 <android::IBinder::~IBinder()+0x2c>:
# We pull out the address and function first. Then we check for an optional
# offset. This is tricky due to functions that look like "operator+(..)+0x2c"
_FUNC = re.compile(r"(^[a-f0-9]*) <(.*)>:$")
_OFFSET = re.compile(r"(.*)\+0x([a-f0-9]*)")
# A disassembly line looks like:
# 177b2: b510 push {r4, lr}
_ASM = re.compile(r"(^[ a-f0-9]*):[ a-f0-0]*.*$")
def _StripPC(addr, cpu_arch):
"""Strips the Thumb bit from a program counter address when appropriate.
Args:
addr: the program counter address
cpu_arch: Target CPU architecture.
Returns:
The stripped program counter address.
"""
if cpu_arch == "arm":
return addr & ~1
return addr
class ObjdumpInformation(object):
def __init__(self, address, library, symbol, offset):
self.address = address
self.library = library
self.symbol = symbol
self.offset = offset
class LLVMObjdumper(object):
def __init__(self):
"""Creates an instance of LLVMObjdumper that interacts with llvm-objdump.
"""
self._llvm_objdump_parameters = [
'--disassemble',
'--demangle',
'--section=.text',
]
def __enter__(self):
return self
def __exit__(self, exc_type, exc_val, exc_tb):
pass
@staticmethod
def GetSymbolDataFromObjdumpOutput(objdump_out, address, cpu_arch):
stripped_target_address = _StripPC(address, cpu_arch)
for line in objdump_out.split(os.linesep):
components = _FUNC.match(line)
if components:
# This is a new function, so record the current function and its
# address.
current_symbol_addr = int(components.group(1), 16)
current_symbol = components.group(2)
# Does it have an optional offset like: "foo(..)+0x2c"?
components = _OFFSET.match(current_symbol)
if components:
current_symbol = components.group(1)
offset = components.group(2)
if offset:
current_symbol_addr -= int(offset, 16)
# Is it a disassembly line like: "177b2: b510 push {r4, lr}"?
components = _ASM.match(line)
if components:
addr = components.group(1)
i_addr = int(addr, 16)
if i_addr == stripped_target_address:
return (current_symbol, stripped_target_address - current_symbol_addr)
return (None, None)
def GetSymbolInformation(self, lib, address, cpu_arch):
"""Returns the corresponding function names and line numbers.
Args:
lib: library to search for info.
address: address to look for info.
cpu_arch: architecture where the dump was taken
Returns:
An ObjdumpInformation object
"""
if not os.path.isfile(_LLVM_OBJDUMP_PATH):
logging.error('Cannot find llvm-objdump. path=%s', _LLVM_OBJDUMP_PATH)
return None
stripped_address = _StripPC(address, cpu_arch)
full_arguments = [_LLVM_OBJDUMP_PATH] + self._llvm_objdump_parameters
full_arguments.append('--start-address=' + str(stripped_address))
full_arguments.append('--stop-address=' + str(stripped_address + 8))
full_arguments.append(lib)
objdump_process = subprocess.Popen(full_arguments,
stdout=subprocess.PIPE,
stdin=subprocess.PIPE,
universal_newlines=True)
stdout, stderr = objdump_process.communicate()
objdump_process_return_code = objdump_process.poll()
if objdump_process_return_code != 0:
logging.error(
'Invocation of llvm-objdump failed!' +
' tool-command-line=\'{}\', return-code={}, std-error=\'{}\''.format(
' '.join(full_arguments), objdump_process_return_code, stderr))
return None
symbol, offset = LLVMObjdumper.GetSymbolDataFromObjdumpOutput(
stdout, address, cpu_arch)
return ObjdumpInformation(address=address,
library=lib,
symbol=symbol,
offset=offset)
|