1 //===- SymbolTable.h --------------------------------------------*- 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 #ifndef LLD_MACHO_SYMBOL_TABLE_H
10 #define LLD_MACHO_SYMBOL_TABLE_H
11 
12 #include "Symbols.h"
13 
14 #include "lld/Common/LLVM.h"
15 #include "llvm/ADT/CachedHashString.h"
16 #include "llvm/ADT/DenseMap.h"
17 #include "llvm/Object/Archive.h"
18 
19 namespace lld::macho {
20 
21 class ArchiveFile;
22 class DylibFile;
23 class InputFile;
24 class ObjFile;
25 class InputSection;
26 class MachHeaderSection;
27 class Symbol;
28 class Defined;
29 class Undefined;
30 
31 /*
32  * Note that the SymbolTable handles name collisions by calling
33  * replaceSymbol(), which does an in-place update of the Symbol via `placement
34  * new`. Therefore, there is no need to update any relocations that hold
35  * pointers the "old" Symbol -- they will automatically point to the new one.
36  */
37 class SymbolTable {
38 public:
39   Defined *addDefined(StringRef name, InputFile *, InputSection *,
40                       uint64_t value, uint64_t size, bool isWeakDef,
41                       bool isPrivateExtern, bool isThumb,
42                       bool isReferencedDynamically, bool noDeadStrip,
43                       bool isWeakDefCanBeHidden);
44 
45   Defined *aliasDefined(Defined *src, StringRef target, InputFile *newFile,
46                         bool makePrivateExtern = false);
47 
48   Symbol *addUndefined(StringRef name, InputFile *, bool isWeakRef);
49 
50   Symbol *addCommon(StringRef name, InputFile *, uint64_t size, uint32_t align,
51                     bool isPrivateExtern);
52 
53   Symbol *addDylib(StringRef name, DylibFile *file, bool isWeakDef, bool isTlv);
54   Symbol *addDynamicLookup(StringRef name);
55 
56   Symbol *addLazyArchive(StringRef name, ArchiveFile *file,
57                          const llvm::object::Archive::Symbol &sym);
58   Symbol *addLazyObject(StringRef name, InputFile &file);
59 
60   Defined *addSynthetic(StringRef name, InputSection *, uint64_t value,
61                         bool isPrivateExtern, bool includeInSymtab,
62                         bool referencedDynamically);
63 
64   ArrayRef<Symbol *> getSymbols() const { return symVector; }
65   Symbol *find(llvm::CachedHashStringRef name);
66   Symbol *find(StringRef name) { return find(llvm::CachedHashStringRef(name)); }
67 
68 private:
69   std::pair<Symbol *, bool> insert(StringRef name, const InputFile *);
70   llvm::DenseMap<llvm::CachedHashStringRef, int> symMap;
71   std::vector<Symbol *> symVector;
72 };
73 
74 void reportPendingUndefinedSymbols();
75 void reportPendingDuplicateSymbols();
76 
77 // Call reportPendingUndefinedSymbols() to emit diagnostics.
78 void treatUndefinedSymbol(const Undefined &, StringRef source);
79 void treatUndefinedSymbol(const Undefined &, const InputSection *,
80                           uint64_t offset);
81 
82 extern std::unique_ptr<SymbolTable> symtab;
83 
84 } // namespace lld::macho
85 
86 #endif
87