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
|
//===- SymbolTable.h --------------------------------------------*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//
#ifndef LLD_ELF_SYMBOL_TABLE_H
#define LLD_ELF_SYMBOL_TABLE_H
#include "Symbols.h"
#include "llvm/ADT/CachedHashString.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/Support/Compiler.h"
namespace lld::elf {
struct Ctx;
class InputFile;
class SharedFile;
struct ArmCmseEntryFunction {
Symbol *acleSeSym;
Symbol *sym;
};
// SymbolTable is a bucket of all known symbols, including defined,
// undefined, or lazy symbols (the last one is symbols in archive
// files whose archive members are not yet loaded).
//
// We put all symbols of all files to a SymbolTable, and the
// SymbolTable selects the "best" symbols if there are name
// conflicts. For example, obviously, a defined symbol is better than
// an undefined symbol. Or, if there's a conflict between a lazy and a
// undefined, it'll read an archive member to read a real definition
// to replace the lazy symbol. The logic is implemented in the
// add*() functions, which are called by input files as they are parsed. There
// is one add* function per symbol type.
class SymbolTable {
public:
SymbolTable(Ctx &ctx) : ctx(ctx) {}
ArrayRef<Symbol *> getSymbols() const { return symVector; }
void wrap(Symbol *sym, Symbol *real, Symbol *wrap);
Symbol *insert(StringRef name);
template <typename T> Symbol *addSymbol(const T &newSym) {
Symbol *sym = insert(newSym.getName());
sym->resolve(ctx, newSym);
return sym;
}
Symbol *addAndCheckDuplicate(Ctx &, const Defined &newSym);
void scanVersionScript();
Symbol *find(StringRef name);
void handleDynamicList();
Symbol *addUnusedUndefined(StringRef name,
uint8_t binding = llvm::ELF::STB_GLOBAL);
// Set of .so files to not link the same shared object file more than once.
llvm::DenseMap<llvm::CachedHashStringRef, SharedFile *> soNames;
// Comdat groups define "link once" sections. If two comdat groups have the
// same name, only one of them is linked, and the other is ignored. This map
// is used to uniquify them.
llvm::DenseMap<llvm::CachedHashStringRef, const InputFile *> comdatGroups;
// The Map of __acle_se_<sym>, <sym> pairs found in the input objects.
// Key is the <sym> name.
llvm::SmallMapVector<StringRef, ArmCmseEntryFunction, 1> cmseSymMap;
// Map of symbols defined in the Arm CMSE import library. The linker must
// preserve the addresses in the output objects.
llvm::StringMap<Defined *> cmseImportLib;
// True if <sym> from the input Arm CMSE import library is written to the
// output Arm CMSE import library.
llvm::StringMap<bool> inCMSEOutImpLib;
private:
SmallVector<Symbol *, 0> findByVersion(SymbolVersion ver);
SmallVector<Symbol *, 0> findAllByVersion(SymbolVersion ver,
bool includeNonDefault);
llvm::StringMap<SmallVector<Symbol *, 0>> &getDemangledSyms();
bool assignExactVersion(SymbolVersion ver, uint16_t versionId,
StringRef versionName, bool includeNonDefault);
void assignWildcardVersion(SymbolVersion ver, uint16_t versionId,
bool includeNonDefault);
Ctx &ctx;
// Global symbols and a map from symbol name to the index. The order is not
// defined. We can use an arbitrary order, but it has to be deterministic even
// when cross linking.
llvm::DenseMap<llvm::CachedHashStringRef, int> symMap;
SmallVector<Symbol *, 0> symVector;
// A map from demangled symbol names to their symbol objects.
// This mapping is 1:N because two symbols with different versions
// can have the same name. We use this map to handle "extern C++ {}"
// directive in version scripts.
std::optional<llvm::StringMap<SmallVector<Symbol *, 0>>> demangledSyms;
};
} // namespace lld::elf
#endif
|
