xref: /freebsd/contrib/llvm-project/lld/COFF/SymbolTable.h (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
10b57cec5SDimitry Andric //===- SymbolTable.h --------------------------------------------*- C++ -*-===//
20b57cec5SDimitry Andric //
30b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
40b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
50b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
60b57cec5SDimitry Andric //
70b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
80b57cec5SDimitry Andric 
90b57cec5SDimitry Andric #ifndef LLD_COFF_SYMBOL_TABLE_H
100b57cec5SDimitry Andric #define LLD_COFF_SYMBOL_TABLE_H
110b57cec5SDimitry Andric 
120b57cec5SDimitry Andric #include "InputFiles.h"
130b57cec5SDimitry Andric #include "LTO.h"
140b57cec5SDimitry Andric #include "llvm/ADT/CachedHashString.h"
150b57cec5SDimitry Andric #include "llvm/ADT/DenseMap.h"
160b57cec5SDimitry Andric #include "llvm/ADT/DenseMapInfo.h"
170b57cec5SDimitry Andric #include "llvm/Support/raw_ostream.h"
180b57cec5SDimitry Andric 
190b57cec5SDimitry Andric namespace llvm {
200b57cec5SDimitry Andric struct LTOCodeGenerator;
210b57cec5SDimitry Andric }
220b57cec5SDimitry Andric 
23*bdd1243dSDimitry Andric namespace lld::coff {
240b57cec5SDimitry Andric 
250b57cec5SDimitry Andric class Chunk;
260b57cec5SDimitry Andric class CommonChunk;
27349cc55cSDimitry Andric class COFFLinkerContext;
280b57cec5SDimitry Andric class Defined;
290b57cec5SDimitry Andric class DefinedAbsolute;
300b57cec5SDimitry Andric class DefinedRegular;
310b57cec5SDimitry Andric class DefinedRelative;
3285868e8aSDimitry Andric class LazyArchive;
330b57cec5SDimitry Andric class SectionChunk;
340b57cec5SDimitry Andric class Symbol;
350b57cec5SDimitry Andric 
360b57cec5SDimitry Andric // SymbolTable is a bucket of all known symbols, including defined,
370b57cec5SDimitry Andric // undefined, or lazy symbols (the last one is symbols in archive
380b57cec5SDimitry Andric // files whose archive members are not yet loaded).
390b57cec5SDimitry Andric //
400b57cec5SDimitry Andric // We put all symbols of all files to a SymbolTable, and the
410b57cec5SDimitry Andric // SymbolTable selects the "best" symbols if there are name
420b57cec5SDimitry Andric // conflicts. For example, obviously, a defined symbol is better than
430b57cec5SDimitry Andric // an undefined symbol. Or, if there's a conflict between a lazy and a
440b57cec5SDimitry Andric // undefined, it'll read an archive member to read a real definition
450b57cec5SDimitry Andric // to replace the lazy symbol. The logic is implemented in the
460b57cec5SDimitry Andric // add*() functions, which are called by input files as they are parsed.
470b57cec5SDimitry Andric // There is one add* function per symbol type.
480b57cec5SDimitry Andric class SymbolTable {
490b57cec5SDimitry Andric public:
50*bdd1243dSDimitry Andric   SymbolTable(COFFLinkerContext &c) : ctx(c) {}
51349cc55cSDimitry Andric 
520b57cec5SDimitry Andric   void addFile(InputFile *file);
530b57cec5SDimitry Andric 
5485868e8aSDimitry Andric   // Emit errors for symbols that cannot be resolved.
5585868e8aSDimitry Andric   void reportUnresolvable();
5685868e8aSDimitry Andric 
570b57cec5SDimitry Andric   // Try to resolve any undefined symbols and update the symbol table
580b57cec5SDimitry Andric   // accordingly, then print an error message for any remaining undefined
5985868e8aSDimitry Andric   // symbols and warn about imported local symbols.
6085868e8aSDimitry Andric   void resolveRemainingUndefines();
610b57cec5SDimitry Andric 
62fe6060f1SDimitry Andric   // Load lazy objects that are needed for MinGW automatic import and for
63fe6060f1SDimitry Andric   // doing stdcall fixups.
64fe6060f1SDimitry Andric   void loadMinGWSymbols();
650b57cec5SDimitry Andric   bool handleMinGWAutomaticImport(Symbol *sym, StringRef name);
660b57cec5SDimitry Andric 
670b57cec5SDimitry Andric   // Returns a list of chunks of selected symbols.
68349cc55cSDimitry Andric   std::vector<Chunk *> getChunks() const;
690b57cec5SDimitry Andric 
700b57cec5SDimitry Andric   // Returns a symbol for a given name. Returns a nullptr if not found.
71349cc55cSDimitry Andric   Symbol *find(StringRef name) const;
72349cc55cSDimitry Andric   Symbol *findUnderscore(StringRef name) const;
730b57cec5SDimitry Andric 
740b57cec5SDimitry Andric   // Occasionally we have to resolve an undefined symbol to its
750b57cec5SDimitry Andric   // mangled symbol. This function tries to find a mangled name
760b57cec5SDimitry Andric   // for U from the symbol table, and if found, set the symbol as
770b57cec5SDimitry Andric   // a weak alias for U.
780b57cec5SDimitry Andric   Symbol *findMangle(StringRef name);
790b57cec5SDimitry Andric 
800b57cec5SDimitry Andric   // Build a set of COFF objects representing the combined contents of
810b57cec5SDimitry Andric   // BitcodeFiles and add them to the symbol table. Called after all files are
820b57cec5SDimitry Andric   // added and before the writer writes results to a file.
83349cc55cSDimitry Andric   void compileBitcodeFiles();
840b57cec5SDimitry Andric 
850b57cec5SDimitry Andric   // Creates an Undefined symbol for a given name.
860b57cec5SDimitry Andric   Symbol *addUndefined(StringRef name);
870b57cec5SDimitry Andric 
880b57cec5SDimitry Andric   Symbol *addSynthetic(StringRef n, Chunk *c);
890b57cec5SDimitry Andric   Symbol *addAbsolute(StringRef n, uint64_t va);
900b57cec5SDimitry Andric 
910b57cec5SDimitry Andric   Symbol *addUndefined(StringRef name, InputFile *f, bool isWeakAlias);
9285868e8aSDimitry Andric   void addLazyArchive(ArchiveFile *f, const Archive::Symbol &sym);
9304eeddc0SDimitry Andric   void addLazyObject(InputFile *f, StringRef n);
94fe6060f1SDimitry Andric   void addLazyDLLSymbol(DLLFile *f, DLLFile::Symbol *sym, StringRef n);
950b57cec5SDimitry Andric   Symbol *addAbsolute(StringRef n, COFFSymbolRef s);
960b57cec5SDimitry Andric   Symbol *addRegular(InputFile *f, StringRef n,
970b57cec5SDimitry Andric                      const llvm::object::coff_symbol_generic *s = nullptr,
98*bdd1243dSDimitry Andric                      SectionChunk *c = nullptr, uint32_t sectionOffset = 0,
99*bdd1243dSDimitry Andric                      bool isWeak = false);
1000b57cec5SDimitry Andric   std::pair<DefinedRegular *, bool>
1010b57cec5SDimitry Andric   addComdat(InputFile *f, StringRef n,
1020b57cec5SDimitry Andric             const llvm::object::coff_symbol_generic *s = nullptr);
1030b57cec5SDimitry Andric   Symbol *addCommon(InputFile *f, StringRef n, uint64_t size,
1040b57cec5SDimitry Andric                     const llvm::object::coff_symbol_generic *s = nullptr,
1050b57cec5SDimitry Andric                     CommonChunk *c = nullptr);
1060b57cec5SDimitry Andric   Symbol *addImportData(StringRef n, ImportFile *f);
1070b57cec5SDimitry Andric   Symbol *addImportThunk(StringRef name, DefinedImportData *s,
1080b57cec5SDimitry Andric                          uint16_t machine);
1090b57cec5SDimitry Andric   void addLibcall(StringRef name);
1100b57cec5SDimitry Andric 
11185868e8aSDimitry Andric   void reportDuplicate(Symbol *existing, InputFile *newFile,
11285868e8aSDimitry Andric                        SectionChunk *newSc = nullptr,
11385868e8aSDimitry Andric                        uint32_t newSectionOffset = 0);
1140b57cec5SDimitry Andric 
1150b57cec5SDimitry Andric   // A list of chunks which to be added to .rdata.
1160b57cec5SDimitry Andric   std::vector<Chunk *> localImportChunks;
1170b57cec5SDimitry Andric 
1180b57cec5SDimitry Andric   // Iterates symbols in non-determinstic hash table order.
1190b57cec5SDimitry Andric   template <typename T> void forEachSymbol(T callback) {
1200b57cec5SDimitry Andric     for (auto &pair : symMap)
1210b57cec5SDimitry Andric       callback(pair.second);
1220b57cec5SDimitry Andric   }
1230b57cec5SDimitry Andric 
1240b57cec5SDimitry Andric private:
12585868e8aSDimitry Andric   /// Given a name without "__imp_" prefix, returns a defined symbol
12685868e8aSDimitry Andric   /// with the "__imp_" prefix, if it exists.
12785868e8aSDimitry Andric   Defined *impSymbol(StringRef name);
1280b57cec5SDimitry Andric   /// Inserts symbol if not already present.
1290b57cec5SDimitry Andric   std::pair<Symbol *, bool> insert(StringRef name);
1300b57cec5SDimitry Andric   /// Same as insert(Name), but also sets isUsedInRegularObj.
1310b57cec5SDimitry Andric   std::pair<Symbol *, bool> insert(StringRef name, InputFile *f);
1320b57cec5SDimitry Andric 
1330b57cec5SDimitry Andric   std::vector<Symbol *> getSymsWithPrefix(StringRef prefix);
1340b57cec5SDimitry Andric 
1350b57cec5SDimitry Andric   llvm::DenseMap<llvm::CachedHashStringRef, Symbol *> symMap;
1360b57cec5SDimitry Andric   std::unique_ptr<BitcodeCompiler> lto;
1370b57cec5SDimitry Andric 
138349cc55cSDimitry Andric   COFFLinkerContext &ctx;
139349cc55cSDimitry Andric };
1400b57cec5SDimitry Andric 
1410b57cec5SDimitry Andric std::vector<std::string> getSymbolLocations(ObjFile *file, uint32_t symIndex);
1420b57cec5SDimitry Andric 
143fe6060f1SDimitry Andric StringRef ltrim1(StringRef s, const char *chars);
144fe6060f1SDimitry Andric 
145*bdd1243dSDimitry Andric } // namespace lld::coff
1460b57cec5SDimitry Andric 
1470b57cec5SDimitry Andric #endif
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