xref: /freebsd/contrib/llvm-project/lld/COFF/Driver.h (revision 5f757f3ff9144b609b3c433dfd370cc6bdc191ad)
1  //===- Driver.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_COFF_DRIVER_H
10  #define LLD_COFF_DRIVER_H
11  
12  #include "Config.h"
13  #include "SymbolTable.h"
14  #include "lld/Common/LLVM.h"
15  #include "lld/Common/Reproduce.h"
16  #include "llvm/ADT/StringRef.h"
17  #include "llvm/ADT/StringSet.h"
18  #include "llvm/Object/Archive.h"
19  #include "llvm/Object/COFF.h"
20  #include "llvm/Option/Arg.h"
21  #include "llvm/Option/ArgList.h"
22  #include "llvm/Support/FileSystem.h"
23  #include "llvm/Support/TarWriter.h"
24  #include "llvm/WindowsDriver/MSVCPaths.h"
25  #include <memory>
26  #include <optional>
27  #include <set>
28  #include <vector>
29  
30  namespace lld::coff {
31  
32  using llvm::COFF::MachineTypes;
33  using llvm::COFF::WindowsSubsystem;
34  using std::optional;
35  
36  class COFFOptTable : public llvm::opt::GenericOptTable {
37  public:
38    COFFOptTable();
39  };
40  
41  // The result of parsing the .drective section. The /export: and /include:
42  // options are handled separately because they reference symbols, and the number
43  // of symbols can be quite large. The LLVM Option library will perform at least
44  // one memory allocation per argument, and that is prohibitively slow for
45  // parsing directives.
46  struct ParsedDirectives {
47    std::vector<StringRef> exports;
48    std::vector<StringRef> includes;
49    std::vector<StringRef> excludes;
50    llvm::opt::InputArgList args;
51  };
52  
53  class ArgParser {
54  public:
55    ArgParser(COFFLinkerContext &ctx);
56  
57    // Parses command line options.
58    llvm::opt::InputArgList parse(llvm::ArrayRef<const char *> args);
59  
60    // Tokenizes a given string and then parses as command line options.
61    llvm::opt::InputArgList parse(StringRef s) { return parse(tokenize(s)); }
62  
63    // Tokenizes a given string and then parses as command line options in
64    // .drectve section. /EXPORT options are returned in second element
65    // to be processed in fastpath.
66    ParsedDirectives parseDirectives(StringRef s);
67  
68  private:
69    // Concatenate LINK environment variable.
70    void addLINK(SmallVector<const char *, 256> &argv);
71  
72    std::vector<const char *> tokenize(StringRef s);
73  
74    COFFLinkerContext &ctx;
75  };
76  
77  class LinkerDriver {
78  public:
79    LinkerDriver(COFFLinkerContext &ctx) : ctx(ctx) {}
80  
81    void linkerMain(llvm::ArrayRef<const char *> args);
82  
83    // Adds various search paths based on the sysroot.  Must only be called once
84    // config->machine has been set.
85    void addWinSysRootLibSearchPaths();
86  
87    void addClangLibSearchPaths(const std::string &argv0);
88  
89    // Used by the resolver to parse .drectve section contents.
90    void parseDirectives(InputFile *file);
91  
92    // Used by ArchiveFile to enqueue members.
93    void enqueueArchiveMember(const Archive::Child &c, const Archive::Symbol &sym,
94                              StringRef parentName);
95  
96    void enqueuePDB(StringRef Path) { enqueuePath(Path, false, false); }
97  
98    MemoryBufferRef takeBuffer(std::unique_ptr<MemoryBuffer> mb);
99  
100    void enqueuePath(StringRef path, bool wholeArchive, bool lazy);
101  
102    std::unique_ptr<llvm::TarWriter> tar; // for /linkrepro
103  
104  private:
105    // Searches a file from search paths.
106    std::optional<StringRef> findFileIfNew(StringRef filename);
107    std::optional<StringRef> findLibIfNew(StringRef filename);
108    StringRef findFile(StringRef filename);
109    StringRef findLib(StringRef filename);
110    StringRef findLibMinGW(StringRef filename);
111  
112    bool findUnderscoreMangle(StringRef sym);
113  
114    // Determines the location of the sysroot based on `args`, environment, etc.
115    void detectWinSysRoot(const llvm::opt::InputArgList &args);
116  
117    // Symbol names are mangled by prepending "_" on x86.
118    StringRef mangle(StringRef sym);
119  
120    llvm::Triple::ArchType getArch();
121  
122    uint64_t getDefaultImageBase();
123  
124    bool isDecorated(StringRef sym);
125  
126    std::string getMapFile(const llvm::opt::InputArgList &args,
127                           llvm::opt::OptSpecifier os,
128                           llvm::opt::OptSpecifier osFile);
129  
130    std::string getImplibPath();
131  
132    // The import name is calculated as follows:
133    //
134    //        | LIBRARY w/ ext |   LIBRARY w/o ext   | no LIBRARY
135    //   -----+----------------+---------------------+------------------
136    //   LINK | {value}        | {value}.{.dll/.exe} | {output name}
137    //    LIB | {value}        | {value}.dll         | {output name}.dll
138    //
139    std::string getImportName(bool asLib);
140  
141    void createImportLibrary(bool asLib);
142  
143    void parseModuleDefs(StringRef path);
144  
145    // Parse an /order file. If an option is given, the linker places COMDAT
146    // sections int he same order as their names appear in the given file.
147    void parseOrderFile(StringRef arg);
148  
149    void parseCallGraphFile(StringRef path);
150  
151    void parsePDBAltPath();
152  
153    // Parses LIB environment which contains a list of search paths.
154    void addLibSearchPaths();
155  
156    // Library search path. The first element is always "" (current directory).
157    std::vector<StringRef> searchPaths;
158  
159    // Convert resource files and potentially merge input resource object
160    // trees into one resource tree.
161    void convertResources();
162  
163    void maybeExportMinGWSymbols(const llvm::opt::InputArgList &args);
164  
165    // We don't want to add the same file more than once.
166    // Files are uniquified by their filesystem and file number.
167    std::set<llvm::sys::fs::UniqueID> visitedFiles;
168  
169    std::set<std::string> visitedLibs;
170  
171    Symbol *addUndefined(StringRef sym);
172  
173    StringRef mangleMaybe(Symbol *s);
174  
175    // Windows specific -- "main" is not the only main function in Windows.
176    // You can choose one from these four -- {w,}{WinMain,main}.
177    // There are four different entry point functions for them,
178    // {w,}{WinMain,main}CRTStartup, respectively. The linker needs to
179    // choose the right one depending on which "main" function is defined.
180    // This function looks up the symbol table and resolve corresponding
181    // entry point name.
182    StringRef findDefaultEntry();
183    WindowsSubsystem inferSubsystem();
184  
185    void addBuffer(std::unique_ptr<MemoryBuffer> mb, bool wholeArchive,
186                   bool lazy);
187    void addArchiveBuffer(MemoryBufferRef mbref, StringRef symName,
188                          StringRef parentName, uint64_t offsetInArchive);
189  
190    void enqueueTask(std::function<void()> task);
191    bool run();
192  
193    std::list<std::function<void()>> taskQueue;
194    std::vector<StringRef> filePaths;
195    std::vector<MemoryBufferRef> resources;
196  
197    llvm::DenseSet<StringRef> directivesExports;
198    llvm::DenseSet<StringRef> excludedSymbols;
199  
200    COFFLinkerContext &ctx;
201  
202    llvm::ToolsetLayout vsLayout = llvm::ToolsetLayout::OlderVS;
203    std::string vcToolChainPath;
204    llvm::SmallString<128> diaPath;
205    bool useWinSysRootLibPath = false;
206    llvm::SmallString<128> universalCRTLibPath;
207    int sdkMajor = 0;
208    llvm::SmallString<128> windowsSdkLibPath;
209  
210    // Functions below this line are defined in DriverUtils.cpp.
211  
212    void printHelp(const char *argv0);
213  
214    // Parses a string in the form of "<integer>[,<integer>]".
215    void parseNumbers(StringRef arg, uint64_t *addr, uint64_t *size = nullptr);
216  
217    void parseGuard(StringRef arg);
218  
219    // Parses a string in the form of "<integer>[.<integer>]".
220    // Minor's default value is 0.
221    void parseVersion(StringRef arg, uint32_t *major, uint32_t *minor);
222  
223    // Parses a string in the form of "<subsystem>[,<integer>[.<integer>]]".
224    void parseSubsystem(StringRef arg, WindowsSubsystem *sys, uint32_t *major,
225                        uint32_t *minor, bool *gotVersion = nullptr);
226  
227    void parseAlternateName(StringRef);
228    void parseMerge(StringRef);
229    void parsePDBPageSize(StringRef);
230    void parseSection(StringRef);
231    void parseAligncomm(StringRef);
232  
233    // Parses a string in the form of "[:<integer>]"
234    void parseFunctionPadMin(llvm::opt::Arg *a);
235  
236    // Parses a string in the form of "[:<integer>]"
237    void parseDependentLoadFlags(llvm::opt::Arg *a);
238  
239    // Parses a string in the form of "EMBED[,=<integer>]|NO".
240    void parseManifest(StringRef arg);
241  
242    // Parses a string in the form of "level=<string>|uiAccess=<string>"
243    void parseManifestUAC(StringRef arg);
244  
245    // Parses a string in the form of "cd|net[,(cd|net)]*"
246    void parseSwaprun(StringRef arg);
247  
248    // Create a resource file containing a manifest XML.
249    std::unique_ptr<MemoryBuffer> createManifestRes();
250    void createSideBySideManifest();
251    std::string createDefaultXml();
252    std::string createManifestXmlWithInternalMt(StringRef defaultXml);
253    std::string createManifestXmlWithExternalMt(StringRef defaultXml);
254    std::string createManifestXml();
255  
256    std::unique_ptr<llvm::WritableMemoryBuffer>
257    createMemoryBufferForManifestRes(size_t manifestRes);
258  
259    // Used for dllexported symbols.
260    Export parseExport(StringRef arg);
261    void fixupExports();
262    void assignExportOrdinals();
263  
264    // Parses a string in the form of "key=value" and check
265    // if value matches previous values for the key.
266    // This feature used in the directive section to reject
267    // incompatible objects.
268    void checkFailIfMismatch(StringRef arg, InputFile *source);
269  
270    // Convert Windows resource files (.res files) to a .obj file.
271    MemoryBufferRef convertResToCOFF(ArrayRef<MemoryBufferRef> mbs,
272                                     ArrayRef<ObjFile *> objs);
273  };
274  
275  // Create enum with OPT_xxx values for each option in Options.td
276  enum {
277    OPT_INVALID = 0,
278  #define OPTION(...) LLVM_MAKE_OPT_ID(__VA_ARGS__),
279  #include "Options.inc"
280  #undef OPTION
281  };
282  
283  } // namespace lld::coff
284  
285  #endif
286