1//===- SymbolicFile.h - Interface that only provides symbols ----*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file declares the SymbolicFile interface.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_OBJECT_SYMBOLICFILE_H
14#define LLVM_OBJECT_SYMBOLICFILE_H
15
16#include "llvm/ADT/iterator_range.h"
17#include "llvm/BinaryFormat/Magic.h"
18#include "llvm/Object/Binary.h"
19#include "llvm/Support/Error.h"
20#include "llvm/Support/Format.h"
21#include "llvm/Support/MemoryBufferRef.h"
22#include <cinttypes>
23#include <cstdint>
24#include <cstring>
25#include <iterator>
26#include <memory>
27
28namespace llvm {
29
30class LLVMContext;
31class raw_ostream;
32
33namespace object {
34
35union DataRefImpl {
36 // This entire union should probably be a
37 // char[max(8, sizeof(uintptr_t))] and require the impl to cast.
38 struct {
39 uint32_t a, b;
40 } d;
41 uintptr_t p;
42
43 DataRefImpl() { std::memset(s: this, c: 0, n: sizeof(DataRefImpl)); }
44};
45
46template <typename OStream>
47OStream& operator<<(OStream &OS, const DataRefImpl &D) {
48 OS << "(" << format(Fmt: "0x%08" PRIxPTR, Vals: D.p) << " (" << format(Fmt: "0x%08x", Vals: D.d.a)
49 << ", " << format(Fmt: "0x%08x", Vals: D.d.b) << "))";
50 return OS;
51}
52
53inline bool operator==(const DataRefImpl &a, const DataRefImpl &b) {
54 // Check bitwise identical. This is the only legal way to compare a union w/o
55 // knowing which member is in use.
56 return std::memcmp(s1: &a, s2: &b, n: sizeof(DataRefImpl)) == 0;
57}
58
59inline bool operator!=(const DataRefImpl &a, const DataRefImpl &b) {
60 return !operator==(a, b);
61}
62
63inline bool operator<(const DataRefImpl &a, const DataRefImpl &b) {
64 // Check bitwise identical. This is the only legal way to compare a union w/o
65 // knowing which member is in use.
66 return std::memcmp(s1: &a, s2: &b, n: sizeof(DataRefImpl)) < 0;
67}
68
69template <class content_type> class content_iterator {
70 content_type Current;
71
72public:
73 using iterator_category = std::forward_iterator_tag;
74 using value_type = content_type;
75 using difference_type = std::ptrdiff_t;
76 using pointer = value_type *;
77 using reference = value_type &;
78
79 content_iterator(content_type symb) : Current(std::move(symb)) {}
80
81 const content_type *operator->() const { return &Current; }
82
83 const content_type &operator*() const { return Current; }
84
85 bool operator==(const content_iterator &other) const {
86 return Current == other.Current;
87 }
88
89 bool operator!=(const content_iterator &other) const {
90 return !(*this == other);
91 }
92
93 content_iterator &operator++() { // preincrement
94 Current.moveNext();
95 return *this;
96 }
97};
98
99class SymbolicFile;
100
101/// This is a value type class that represents a single symbol in the list of
102/// symbols in the object file.
103class BasicSymbolRef {
104 DataRefImpl SymbolPimpl;
105 const SymbolicFile *OwningObject = nullptr;
106
107public:
108 enum Flags : unsigned {
109 SF_None = 0,
110 SF_Undefined = 1U << 0, // Symbol is defined in another object file
111 SF_Global = 1U << 1, // Global symbol
112 SF_Weak = 1U << 2, // Weak symbol
113 SF_Absolute = 1U << 3, // Absolute symbol
114 SF_Common = 1U << 4, // Symbol has common linkage
115 SF_Indirect = 1U << 5, // Symbol is an alias to another symbol
116 SF_Exported = 1U << 6, // Symbol is visible to other DSOs
117 SF_FormatSpecific = 1U << 7, // Specific to the object file format
118 // (e.g. section symbols)
119 SF_Thumb = 1U << 8, // Thumb symbol in a 32-bit ARM binary
120 SF_Hidden = 1U << 9, // Symbol has hidden visibility
121 SF_Const = 1U << 10, // Symbol value is constant
122 SF_Executable = 1U << 11, // Symbol points to an executable section
123 // (IR only)
124 };
125
126 BasicSymbolRef() = default;
127 BasicSymbolRef(DataRefImpl SymbolP, const SymbolicFile *Owner);
128
129 bool operator==(const BasicSymbolRef &Other) const;
130 bool operator<(const BasicSymbolRef &Other) const;
131
132 void moveNext();
133
134 Error printName(raw_ostream &OS) const;
135
136 /// Get symbol flags (bitwise OR of SymbolRef::Flags)
137 Expected<uint32_t> getFlags() const;
138
139 DataRefImpl getRawDataRefImpl() const;
140 const SymbolicFile *getObject() const;
141};
142
143using basic_symbol_iterator = content_iterator<BasicSymbolRef>;
144
145class SymbolicFile : public Binary {
146public:
147 SymbolicFile(unsigned int Type, MemoryBufferRef Source);
148 ~SymbolicFile() override;
149
150 // virtual interface.
151 virtual void moveSymbolNext(DataRefImpl &Symb) const = 0;
152
153 virtual Error printSymbolName(raw_ostream &OS, DataRefImpl Symb) const = 0;
154
155 virtual Expected<uint32_t> getSymbolFlags(DataRefImpl Symb) const = 0;
156
157 virtual basic_symbol_iterator symbol_begin() const = 0;
158
159 virtual basic_symbol_iterator symbol_end() const = 0;
160
161 virtual bool is64Bit() const = 0;
162
163 // convenience wrappers.
164 using basic_symbol_iterator_range = iterator_range<basic_symbol_iterator>;
165 basic_symbol_iterator_range symbols() const {
166 return basic_symbol_iterator_range(symbol_begin(), symbol_end());
167 }
168
169 // construction aux.
170 static Expected<std::unique_ptr<SymbolicFile>>
171 createSymbolicFile(MemoryBufferRef Object, llvm::file_magic Type,
172 LLVMContext *Context, bool InitContent = true);
173
174 static Expected<std::unique_ptr<SymbolicFile>>
175 createSymbolicFile(MemoryBufferRef Object) {
176 return createSymbolicFile(Object, Type: llvm::file_magic::unknown, Context: nullptr);
177 }
178
179 static bool classof(const Binary *v) {
180 return v->isSymbolic();
181 }
182
183 static bool isSymbolicFile(file_magic Type, const LLVMContext *Context);
184};
185
186inline BasicSymbolRef::BasicSymbolRef(DataRefImpl SymbolP,
187 const SymbolicFile *Owner)
188 : SymbolPimpl(SymbolP), OwningObject(Owner) {}
189
190inline bool BasicSymbolRef::operator==(const BasicSymbolRef &Other) const {
191 return SymbolPimpl == Other.SymbolPimpl;
192}
193
194inline bool BasicSymbolRef::operator<(const BasicSymbolRef &Other) const {
195 return SymbolPimpl < Other.SymbolPimpl;
196}
197
198inline void BasicSymbolRef::moveNext() {
199 return OwningObject->moveSymbolNext(Symb&: SymbolPimpl);
200}
201
202inline Error BasicSymbolRef::printName(raw_ostream &OS) const {
203 return OwningObject->printSymbolName(OS, Symb: SymbolPimpl);
204}
205
206inline Expected<uint32_t> BasicSymbolRef::getFlags() const {
207 return OwningObject->getSymbolFlags(Symb: SymbolPimpl);
208}
209
210inline DataRefImpl BasicSymbolRef::getRawDataRefImpl() const {
211 return SymbolPimpl;
212}
213
214inline const SymbolicFile *BasicSymbolRef::getObject() const {
215 return OwningObject;
216}
217
218} // end namespace object
219} // end namespace llvm
220
221#endif // LLVM_OBJECT_SYMBOLICFILE_H
222

source code of llvm/include/llvm/Object/SymbolicFile.h