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
30namespace lld::coff {
31
32using llvm::COFF::MachineTypes;
33using llvm::COFF::WindowsSubsystem;
34using std::optional;
35
36class COFFOptTable : public llvm::opt::GenericOptTable {
37public:
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.
46struct ParsedDirectives {
47  std::vector<StringRef> exports;
48  std::vector<StringRef> includes;
49  std::vector<StringRef> excludes;
50  llvm::opt::InputArgList args;
51};
52
53class ArgParser {
54public:
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
68private:
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
77class LinkerDriver {
78public:
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
104private:
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
276enum {
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