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
|
//===--- DWARFExpression.h - DWARF Expression handling ----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_DEBUGINFO_DWARFEXPRESSION_H
#define LLVM_DEBUGINFO_DWARFEXPRESSION_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/iterator.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/Support/DataExtractor.h"
namespace llvm {
class DWARFUnit;
class MCRegisterInfo;
class raw_ostream;
class DWARFExpression {
public:
class iterator;
/// This class represents an Operation in the Expression. Each operation can
/// have up to 2 oprerands.
///
/// An Operation can be in Error state (check with isError()). This
/// means that it couldn't be decoded successfully and if it is the
/// case, all others fields contain undefined values.
class Operation {
public:
/// Size and signedness of expression operations' operands.
enum Encoding : uint8_t {
Size1 = 0,
Size2 = 1,
Size4 = 2,
Size8 = 3,
SizeLEB = 4,
SizeAddr = 5,
SizeRefAddr = 6,
SizeBlock = 7, ///< Preceding operand contains block size
SignBit = 0x8,
SignedSize1 = SignBit | Size1,
SignedSize2 = SignBit | Size2,
SignedSize4 = SignBit | Size4,
SignedSize8 = SignBit | Size8,
SignedSizeLEB = SignBit | SizeLEB,
SizeNA = 0xFF ///< Unused operands get this encoding.
};
enum DwarfVersion : uint8_t {
DwarfNA, ///< Serves as a marker for unused entries
Dwarf2 = 2,
Dwarf3,
Dwarf4
};
/// Description of the encoding of one expression Op.
struct Description {
DwarfVersion Version; ///< Dwarf version where the Op was introduced.
Encoding Op[2]; ///< Encoding for Op operands, or SizeNA.
Description(DwarfVersion Version = DwarfNA, Encoding Op1 = SizeNA,
Encoding Op2 = SizeNA)
: Version(Version) {
Op[0] = Op1;
Op[1] = Op2;
}
};
private:
friend class DWARFExpression::iterator;
uint8_t Opcode; ///< The Op Opcode, DW_OP_<something>.
Description Desc;
bool Error;
uint32_t EndOffset;
uint64_t Operands[2];
public:
Description &getDescription() { return Desc; }
uint8_t getCode() { return Opcode; }
uint64_t getRawOperand(unsigned Idx) { return Operands[Idx]; }
uint32_t getEndOffset() { return EndOffset; }
bool extract(DataExtractor Data, uint16_t Version, uint8_t AddressSize,
uint32_t Offset);
bool isError() { return Error; }
bool print(raw_ostream &OS, const DWARFExpression *U,
const MCRegisterInfo *RegInfo, bool isEH);
};
/// An iterator to go through the expression operations.
class iterator
: public iterator_facade_base<iterator, std::forward_iterator_tag,
Operation> {
friend class DWARFExpression;
const DWARFExpression *Expr;
uint32_t Offset;
Operation Op;
iterator(const DWARFExpression *Expr, uint32_t Offset)
: Expr(Expr), Offset(Offset) {
Op.Error =
Offset >= Expr->Data.getData().size() ||
!Op.extract(Expr->Data, Expr->Version, Expr->AddressSize, Offset);
}
public:
class Operation &operator++() {
Offset = Op.isError() ? Expr->Data.getData().size() : Op.EndOffset;
Op.Error =
Offset >= Expr->Data.getData().size() ||
!Op.extract(Expr->Data, Expr->Version, Expr->AddressSize, Offset);
return Op;
}
class Operation &operator*() {
return Op;
}
// Comparison operators are provided out of line.
friend bool operator==(const iterator &, const iterator &);
};
DWARFExpression(DataExtractor Data, uint16_t Version, uint8_t AddressSize)
: Data(Data), Version(Version), AddressSize(AddressSize) {
assert(AddressSize == 8 || AddressSize == 4);
}
iterator begin() const { return iterator(this, 0); }
iterator end() const { return iterator(this, Data.getData().size()); }
void print(raw_ostream &OS, const MCRegisterInfo *RegInfo,
bool IsEH = false) const;
private:
DataExtractor Data;
uint16_t Version;
uint8_t AddressSize;
};
inline bool operator==(const DWARFExpression::iterator &LHS,
const DWARFExpression::iterator &RHS) {
return LHS.Expr == RHS.Expr && LHS.Offset == RHS.Offset;
}
inline bool operator!=(const DWARFExpression::iterator &LHS,
const DWARFExpression::iterator &RHS) {
return !(LHS == RHS);
}
}
#endif
|
