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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
//===- DWARFGdbIndex.cpp --------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/DebugInfo/DWARF/DWARFGdbIndex.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/DataExtractor.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
#include <cinttypes>
#include <cstdint>
#include <utility>
using namespace llvm;
// .gdb_index section format reference:
// https://sourceware.org/gdb/onlinedocs/gdb/Index-Section-Format.html
void DWARFGdbIndex::dumpCUList(raw_ostream &OS) const {
OS << format("\n CU list offset = 0x%x, has %" PRId64 " entries:",
CuListOffset, (uint64_t)CuList.size())
<< '\n';
uint32_t I = 0;
for (const CompUnitEntry &CU : CuList)
OS << format(" %d: Offset = 0x%llx, Length = 0x%llx\n", I++, CU.Offset,
CU.Length);
}
void DWARFGdbIndex::dumpTUList(raw_ostream &OS) const {
OS << formatv("\n Types CU list offset = {0:x}, has {1} entries:\n",
TuListOffset, TuList.size());
uint32_t I = 0;
for (const TypeUnitEntry &TU : TuList)
OS << formatv(" {0}: offset = {1:x8}, type_offset = {2:x8}, "
"type_signature = {3:x16}\n",
I++, TU.Offset, TU.TypeOffset, TU.TypeSignature);
}
void DWARFGdbIndex::dumpAddressArea(raw_ostream &OS) const {
OS << format("\n Address area offset = 0x%x, has %" PRId64 " entries:",
AddressAreaOffset, (uint64_t)AddressArea.size())
<< '\n';
for (const AddressEntry &Addr : AddressArea)
OS << format(
" Low/High address = [0x%llx, 0x%llx) (Size: 0x%llx), CU id = %d\n",
Addr.LowAddress, Addr.HighAddress, Addr.HighAddress - Addr.LowAddress,
Addr.CuIndex);
}
void DWARFGdbIndex::dumpSymbolTable(raw_ostream &OS) const {
OS << format("\n Symbol table offset = 0x%x, size = %" PRId64
", filled slots:",
SymbolTableOffset, (uint64_t)SymbolTable.size())
<< '\n';
uint32_t I = -1;
for (const SymTableEntry &E : SymbolTable) {
++I;
if (!E.NameOffset && !E.VecOffset)
continue;
OS << format(" %d: Name offset = 0x%x, CU vector offset = 0x%x\n", I,
E.NameOffset, E.VecOffset);
StringRef Name = ConstantPoolStrings.substr(
ConstantPoolOffset - StringPoolOffset + E.NameOffset);
auto CuVector = llvm::find_if(
ConstantPoolVectors,
[&](const std::pair<uint32_t, SmallVector<uint32_t, 0>> &V) {
return V.first == E.VecOffset;
});
assert(CuVector != ConstantPoolVectors.end() && "Invalid symbol table");
uint32_t CuVectorId = CuVector - ConstantPoolVectors.begin();
OS << format(" String name: %s, CU vector index: %d\n", Name.data(),
CuVectorId);
}
}
void DWARFGdbIndex::dumpConstantPool(raw_ostream &OS) const {
OS << format("\n Constant pool offset = 0x%x, has %" PRId64 " CU vectors:",
ConstantPoolOffset, (uint64_t)ConstantPoolVectors.size());
uint32_t I = 0;
for (const auto &V : ConstantPoolVectors) {
OS << format("\n %d(0x%x): ", I++, V.first);
for (uint32_t Val : V.second)
OS << format("0x%x ", Val);
}
OS << '\n';
}
void DWARFGdbIndex::dump(raw_ostream &OS) {
if (HasError) {
OS << "\n<error parsing>\n";
return;
}
if (HasContent) {
OS << " Version = " << Version << '\n';
dumpCUList(OS);
dumpTUList(OS);
dumpAddressArea(OS);
dumpSymbolTable(OS);
dumpConstantPool(OS);
}
}
bool DWARFGdbIndex::parseImpl(DataExtractor Data) {
uint64_t Offset = 0;
// Only version 7 is supported at this moment.
Version = Data.getU32(&Offset);
if (Version != 7)
return false;
CuListOffset = Data.getU32(&Offset);
TuListOffset = Data.getU32(&Offset);
AddressAreaOffset = Data.getU32(&Offset);
SymbolTableOffset = Data.getU32(&Offset);
ConstantPoolOffset = Data.getU32(&Offset);
if (Offset != CuListOffset)
return false;
uint32_t CuListSize = (TuListOffset - CuListOffset) / 16;
CuList.reserve(CuListSize);
for (uint32_t i = 0; i < CuListSize; ++i) {
uint64_t CuOffset = Data.getU64(&Offset);
uint64_t CuLength = Data.getU64(&Offset);
CuList.push_back({CuOffset, CuLength});
}
// CU Types are no longer needed as DWARF skeleton type units never made it
// into the standard.
uint32_t TuListSize = (AddressAreaOffset - TuListOffset) / 24;
TuList.resize(TuListSize);
for (uint32_t I = 0; I < TuListSize; ++I) {
uint64_t CuOffset = Data.getU64(&Offset);
uint64_t TypeOffset = Data.getU64(&Offset);
uint64_t Signature = Data.getU64(&Offset);
TuList[I] = {CuOffset, TypeOffset, Signature};
}
uint32_t AddressAreaSize = (SymbolTableOffset - AddressAreaOffset) / 20;
AddressArea.reserve(AddressAreaSize);
for (uint32_t i = 0; i < AddressAreaSize; ++i) {
uint64_t LowAddress = Data.getU64(&Offset);
uint64_t HighAddress = Data.getU64(&Offset);
uint32_t CuIndex = Data.getU32(&Offset);
AddressArea.push_back({LowAddress, HighAddress, CuIndex});
}
// The symbol table. This is an open addressed hash table. The size of the
// hash table is always a power of 2.
// Each slot in the hash table consists of a pair of offset_type values. The
// first value is the offset of the symbol's name in the constant pool. The
// second value is the offset of the CU vector in the constant pool.
// If both values are 0, then this slot in the hash table is empty. This is ok
// because while 0 is a valid constant pool index, it cannot be a valid index
// for both a string and a CU vector.
uint32_t SymTableSize = (ConstantPoolOffset - SymbolTableOffset) / 8;
SymbolTable.reserve(SymTableSize);
uint32_t CuVectorsTotal = 0;
for (uint32_t i = 0; i < SymTableSize; ++i) {
uint32_t NameOffset = Data.getU32(&Offset);
uint32_t CuVecOffset = Data.getU32(&Offset);
SymbolTable.push_back({NameOffset, CuVecOffset});
if (NameOffset || CuVecOffset)
++CuVectorsTotal;
}
// The constant pool. CU vectors are stored first, followed by strings.
// The first value is the number of CU indices in the vector. Each subsequent
// value is the index and symbol attributes of a CU in the CU list.
for (uint32_t i = 0; i < CuVectorsTotal; ++i) {
ConstantPoolVectors.emplace_back(0, SmallVector<uint32_t, 0>());
auto &Vec = ConstantPoolVectors.back();
Vec.first = Offset - ConstantPoolOffset;
uint32_t Num = Data.getU32(&Offset);
for (uint32_t j = 0; j < Num; ++j)
Vec.second.push_back(Data.getU32(&Offset));
}
ConstantPoolStrings = Data.getData().drop_front(Offset);
StringPoolOffset = Offset;
return true;
}
void DWARFGdbIndex::parse(DataExtractor Data) {
HasContent = !Data.getData().empty();
HasError = HasContent && !parseImpl(Data);
}
|
