1 //===- DriverUtils.cpp ----------------------------------------------------===// 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 #include "Config.h" 10 #include "Driver.h" 11 #include "InputFiles.h" 12 #include "ObjC.h" 13 #include "Target.h" 14 15 #include "lld/Common/Args.h" 16 #include "lld/Common/CommonLinkerContext.h" 17 #include "lld/Common/Reproduce.h" 18 #include "llvm/ADT/CachedHashString.h" 19 #include "llvm/ADT/DenseMap.h" 20 #include "llvm/LTO/LTO.h" 21 #include "llvm/Option/Arg.h" 22 #include "llvm/Option/ArgList.h" 23 #include "llvm/Option/Option.h" 24 #include "llvm/Support/CommandLine.h" 25 #include "llvm/Support/FileSystem.h" 26 #include "llvm/Support/Path.h" 27 #include "llvm/TextAPI/InterfaceFile.h" 28 #include "llvm/TextAPI/TextAPIReader.h" 29 30 using namespace llvm; 31 using namespace llvm::MachO; 32 using namespace llvm::opt; 33 using namespace llvm::sys; 34 using namespace lld; 35 using namespace lld::macho; 36 37 // Create prefix string literals used in Options.td 38 #define PREFIX(NAME, VALUE) const char *NAME[] = VALUE; 39 #include "Options.inc" 40 #undef PREFIX 41 42 // Create table mapping all options defined in Options.td 43 static const OptTable::Info optInfo[] = { 44 #define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X7, X8, X9, X10, X11, X12) \ 45 {X1, X2, X10, X11, OPT_##ID, Option::KIND##Class, \ 46 X9, X8, OPT_##GROUP, OPT_##ALIAS, X7, X12}, 47 #include "Options.inc" 48 #undef OPTION 49 }; 50 51 MachOOptTable::MachOOptTable() : OptTable(optInfo) {} 52 53 // Set color diagnostics according to --color-diagnostics={auto,always,never} 54 // or --no-color-diagnostics flags. 55 static void handleColorDiagnostics(InputArgList &args) { 56 const Arg *arg = 57 args.getLastArg(OPT_color_diagnostics, OPT_color_diagnostics_eq, 58 OPT_no_color_diagnostics); 59 if (!arg) 60 return; 61 if (arg->getOption().getID() == OPT_color_diagnostics) { 62 lld::errs().enable_colors(true); 63 } else if (arg->getOption().getID() == OPT_no_color_diagnostics) { 64 lld::errs().enable_colors(false); 65 } else { 66 StringRef s = arg->getValue(); 67 if (s == "always") 68 lld::errs().enable_colors(true); 69 else if (s == "never") 70 lld::errs().enable_colors(false); 71 else if (s != "auto") 72 error("unknown option: --color-diagnostics=" + s); 73 } 74 } 75 76 InputArgList MachOOptTable::parse(ArrayRef<const char *> argv) { 77 // Make InputArgList from string vectors. 78 unsigned missingIndex; 79 unsigned missingCount; 80 SmallVector<const char *, 256> vec(argv.data(), argv.data() + argv.size()); 81 82 // Expand response files (arguments in the form of @<filename>) 83 // and then parse the argument again. 84 cl::ExpandResponseFiles(saver(), cl::TokenizeGNUCommandLine, vec); 85 InputArgList args = ParseArgs(vec, missingIndex, missingCount); 86 87 // Handle -fatal_warnings early since it converts missing argument warnings 88 // to errors. 89 errorHandler().fatalWarnings = args.hasArg(OPT_fatal_warnings); 90 errorHandler().suppressWarnings = args.hasArg(OPT_w); 91 92 if (missingCount) 93 error(Twine(args.getArgString(missingIndex)) + ": missing argument"); 94 95 handleColorDiagnostics(args); 96 97 for (const Arg *arg : args.filtered(OPT_UNKNOWN)) { 98 std::string nearest; 99 if (findNearest(arg->getAsString(args), nearest) > 1) 100 error("unknown argument '" + arg->getAsString(args) + "'"); 101 else 102 error("unknown argument '" + arg->getAsString(args) + 103 "', did you mean '" + nearest + "'"); 104 } 105 return args; 106 } 107 108 void MachOOptTable::printHelp(const char *argv0, bool showHidden) const { 109 OptTable::printHelp(lld::outs(), 110 (std::string(argv0) + " [options] file...").c_str(), 111 "LLVM Linker", showHidden); 112 lld::outs() << "\n"; 113 } 114 115 static std::string rewritePath(StringRef s) { 116 if (fs::exists(s)) 117 return relativeToRoot(s); 118 return std::string(s); 119 } 120 121 static std::string rewriteInputPath(StringRef s) { 122 // Don't bother rewriting "absolute" paths that are actually under the 123 // syslibroot; simply rewriting the syslibroot is sufficient. 124 if (rerootPath(s) == s && fs::exists(s)) 125 return relativeToRoot(s); 126 return std::string(s); 127 } 128 129 // Reconstructs command line arguments so that so that you can re-run 130 // the same command with the same inputs. This is for --reproduce. 131 std::string macho::createResponseFile(const InputArgList &args) { 132 SmallString<0> data; 133 raw_svector_ostream os(data); 134 135 // Copy the command line to the output while rewriting paths. 136 for (const Arg *arg : args) { 137 switch (arg->getOption().getID()) { 138 case OPT_reproduce: 139 break; 140 case OPT_INPUT: 141 os << quote(rewriteInputPath(arg->getValue())) << "\n"; 142 break; 143 case OPT_o: 144 os << "-o " << quote(path::filename(arg->getValue())) << "\n"; 145 break; 146 case OPT_filelist: 147 if (Optional<MemoryBufferRef> buffer = readFile(arg->getValue())) 148 for (StringRef path : args::getLines(*buffer)) 149 os << quote(rewriteInputPath(path)) << "\n"; 150 break; 151 case OPT_force_load: 152 case OPT_weak_library: 153 os << arg->getSpelling() << " " 154 << quote(rewriteInputPath(arg->getValue())) << "\n"; 155 break; 156 case OPT_F: 157 case OPT_L: 158 case OPT_bundle_loader: 159 case OPT_exported_symbols_list: 160 case OPT_order_file: 161 case OPT_rpath: 162 case OPT_syslibroot: 163 case OPT_unexported_symbols_list: 164 os << arg->getSpelling() << " " << quote(rewritePath(arg->getValue())) 165 << "\n"; 166 break; 167 case OPT_sectcreate: 168 os << arg->getSpelling() << " " << quote(arg->getValue(0)) << " " 169 << quote(arg->getValue(1)) << " " 170 << quote(rewritePath(arg->getValue(2))) << "\n"; 171 break; 172 default: 173 os << toString(*arg) << "\n"; 174 } 175 } 176 return std::string(data.str()); 177 } 178 179 static void searchedDylib(const Twine &path, bool found) { 180 if (config->printDylibSearch) 181 message("searched " + path + (found ? ", found " : ", not found")); 182 if (!found) 183 depTracker->logFileNotFound(path); 184 } 185 186 Optional<StringRef> macho::resolveDylibPath(StringRef dylibPath) { 187 // TODO: if a tbd and dylib are both present, we should check to make sure 188 // they are consistent. 189 SmallString<261> tbdPath = dylibPath; 190 path::replace_extension(tbdPath, ".tbd"); 191 bool tbdExists = fs::exists(tbdPath); 192 searchedDylib(tbdPath, tbdExists); 193 if (tbdExists) 194 return saver().save(tbdPath.str()); 195 196 bool dylibExists = fs::exists(dylibPath); 197 searchedDylib(dylibPath, dylibExists); 198 if (dylibExists) 199 return saver().save(dylibPath); 200 return {}; 201 } 202 203 // It's not uncommon to have multiple attempts to load a single dylib, 204 // especially if it's a commonly re-exported core library. 205 static DenseMap<CachedHashStringRef, DylibFile *> loadedDylibs; 206 207 DylibFile *macho::loadDylib(MemoryBufferRef mbref, DylibFile *umbrella, 208 bool isBundleLoader, bool explicitlyLinked) { 209 CachedHashStringRef path(mbref.getBufferIdentifier()); 210 DylibFile *&file = loadedDylibs[path]; 211 if (file) { 212 if (explicitlyLinked) 213 file->explicitlyLinked = explicitlyLinked; 214 return file; 215 } 216 217 DylibFile *newFile; 218 file_magic magic = identify_magic(mbref.getBuffer()); 219 if (magic == file_magic::tapi_file) { 220 Expected<std::unique_ptr<InterfaceFile>> result = TextAPIReader::get(mbref); 221 if (!result) { 222 error("could not load TAPI file at " + mbref.getBufferIdentifier() + 223 ": " + toString(result.takeError())); 224 return nullptr; 225 } 226 file = 227 make<DylibFile>(**result, umbrella, isBundleLoader, explicitlyLinked); 228 229 // parseReexports() can recursively call loadDylib(). That's fine since 230 // we wrote the DylibFile we just loaded to the loadDylib cache via the 231 // `file` reference. But the recursive load can grow loadDylibs, so the 232 // `file` reference might become invalid after parseReexports() -- so copy 233 // the pointer it refers to before continuing. 234 newFile = file; 235 if (newFile->exportingFile) 236 newFile->parseReexports(**result); 237 } else { 238 assert(magic == file_magic::macho_dynamically_linked_shared_lib || 239 magic == file_magic::macho_dynamically_linked_shared_lib_stub || 240 magic == file_magic::macho_executable || 241 magic == file_magic::macho_bundle); 242 file = make<DylibFile>(mbref, umbrella, isBundleLoader, explicitlyLinked); 243 244 // parseLoadCommands() can also recursively call loadDylib(). See comment 245 // in previous block for why this means we must copy `file` here. 246 newFile = file; 247 if (newFile->exportingFile) 248 newFile->parseLoadCommands(mbref); 249 } 250 return newFile; 251 } 252 253 void macho::resetLoadedDylibs() { loadedDylibs.clear(); } 254 255 Optional<StringRef> 256 macho::findPathCombination(const Twine &name, 257 const std::vector<StringRef> &roots, 258 ArrayRef<StringRef> extensions) { 259 SmallString<261> base; 260 for (StringRef dir : roots) { 261 base = dir; 262 path::append(base, name); 263 for (StringRef ext : extensions) { 264 Twine location = base + ext; 265 bool exists = fs::exists(location); 266 searchedDylib(location, exists); 267 if (exists) 268 return saver().save(location.str()); 269 } 270 } 271 return {}; 272 } 273 274 StringRef macho::rerootPath(StringRef path) { 275 if (!path::is_absolute(path, path::Style::posix) || path.endswith(".o")) 276 return path; 277 278 if (Optional<StringRef> rerootedPath = 279 findPathCombination(path, config->systemLibraryRoots)) 280 return *rerootedPath; 281 282 return path; 283 } 284 285 uint32_t macho::getModTime(StringRef path) { 286 if (config->zeroModTime) 287 return 0; 288 289 fs::file_status stat; 290 if (!fs::status(path, stat)) 291 if (fs::exists(stat)) 292 return toTimeT(stat.getLastModificationTime()); 293 294 warn("failed to get modification time of " + path); 295 return 0; 296 } 297 298 void macho::printArchiveMemberLoad(StringRef reason, const InputFile *f) { 299 if (config->printEachFile) 300 message(toString(f)); 301 if (config->printWhyLoad) 302 message(reason + " forced load of " + toString(f)); 303 } 304 305 macho::DependencyTracker::DependencyTracker(StringRef path) 306 : path(path), active(!path.empty()) { 307 if (active && fs::exists(path) && !fs::can_write(path)) { 308 warn("Ignoring dependency_info option since specified path is not " 309 "writeable."); 310 active = false; 311 } 312 } 313 314 void macho::DependencyTracker::write(StringRef version, 315 const SetVector<InputFile *> &inputs, 316 StringRef output) { 317 if (!active) 318 return; 319 320 std::error_code ec; 321 raw_fd_ostream os(path, ec, fs::OF_None); 322 if (ec) { 323 warn("Error writing dependency info to file"); 324 return; 325 } 326 327 auto addDep = [&os](DepOpCode opcode, const StringRef &path) { 328 // XXX: Even though DepOpCode's underlying type is uint8_t, 329 // this cast is still needed because Clang older than 10.x has a bug, 330 // where it doesn't know to cast the enum to its underlying type. 331 // Hence `<< DepOpCode` is ambiguous to it. 332 os << static_cast<uint8_t>(opcode); 333 os << path; 334 os << '\0'; 335 }; 336 337 addDep(DepOpCode::Version, version); 338 339 // Sort the input by its names. 340 std::vector<StringRef> inputNames; 341 inputNames.reserve(inputs.size()); 342 for (InputFile *f : inputs) 343 inputNames.push_back(f->getName()); 344 llvm::sort(inputNames); 345 346 for (const StringRef &in : inputNames) 347 addDep(DepOpCode::Input, in); 348 349 for (const std::string &f : notFounds) 350 addDep(DepOpCode::NotFound, f); 351 352 addDep(DepOpCode::Output, output); 353 } 354