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
|
//===- SymbolTable.h --------------------------------------------*- C++ -*-===//
//
// The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef LLD_WASM_SYMBOL_TABLE_H
#define LLD_WASM_SYMBOL_TABLE_H
#include "InputFiles.h"
#include "LTO.h"
#include "Symbols.h"
#include "lld/Common/LLVM.h"
#include "llvm/ADT/CachedHashString.h"
#include "llvm/ADT/DenseSet.h"
namespace lld {
namespace wasm {
class InputSegment;
// 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:
void addFile(InputFile *File);
void addCombinedLTOObject();
std::vector<ObjFile *> ObjectFiles;
std::vector<BitcodeFile *> BitcodeFiles;
std::vector<InputFunction *> SyntheticFunctions;
std::vector<InputGlobal *> SyntheticGlobals;
void reportRemainingUndefines();
ArrayRef<Symbol *> getSymbols() const { return SymVector; }
Symbol *find(StringRef Name);
Symbol *addDefinedFunction(StringRef Name, uint32_t Flags, InputFile *File,
InputFunction *Function);
Symbol *addDefinedData(StringRef Name, uint32_t Flags, InputFile *File,
InputSegment *Segment, uint32_t Address,
uint32_t Size);
Symbol *addDefinedGlobal(StringRef Name, uint32_t Flags, InputFile *File,
InputGlobal *G);
Symbol *addDefinedEvent(StringRef Name, uint32_t Flags, InputFile *File,
InputEvent *E);
Symbol *addUndefinedFunction(StringRef Name, StringRef ImportName,
StringRef ImportModule, uint32_t Flags,
InputFile *File, const WasmSignature *Signature);
Symbol *addUndefinedData(StringRef Name, uint32_t Flags, InputFile *File);
Symbol *addUndefinedGlobal(StringRef Name, StringRef ImportName,
StringRef ImportModule, uint32_t Flags,
InputFile *File, const WasmGlobalType *Type);
void addLazy(ArchiveFile *F, const llvm::object::Archive::Symbol *Sym);
bool addComdat(StringRef Name);
DefinedData *addSyntheticDataSymbol(StringRef Name, uint32_t Flags);
DefinedGlobal *addSyntheticGlobal(StringRef Name, uint32_t Flags,
InputGlobal *Global);
DefinedFunction *addSyntheticFunction(StringRef Name, uint32_t Flags,
InputFunction *Function);
private:
std::pair<Symbol *, bool> insert(StringRef Name, InputFile *File);
llvm::DenseMap<llvm::CachedHashStringRef, Symbol *> SymMap;
std::vector<Symbol *> SymVector;
llvm::DenseSet<llvm::CachedHashStringRef> Comdats;
// For LTO.
std::unique_ptr<BitcodeCompiler> LTO;
};
extern SymbolTable *Symtab;
} // namespace wasm
} // namespace lld
#endif
|
