1 //===- DriverUtils.cpp ----------------------------------------------------===//
2 //
3 // The LLVM Linker
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains utility functions for the driver. Because there
11 // are so many small functions, we created this separate file to make
12 // Driver.cpp less cluttered.
13 //
14 //===----------------------------------------------------------------------===//
15
16 #include "Config.h"
17 #include "Driver.h"
18 #include "Symbols.h"
19 #include "lld/Common/ErrorHandler.h"
20 #include "lld/Common/Memory.h"
21 #include "llvm/ADT/Optional.h"
22 #include "llvm/ADT/StringSwitch.h"
23 #include "llvm/BinaryFormat/COFF.h"
24 #include "llvm/Object/COFF.h"
25 #include "llvm/Object/WindowsResource.h"
26 #include "llvm/Option/Arg.h"
27 #include "llvm/Option/ArgList.h"
28 #include "llvm/Option/Option.h"
29 #include "llvm/Support/CommandLine.h"
30 #include "llvm/Support/FileUtilities.h"
31 #include "llvm/Support/MathExtras.h"
32 #include "llvm/Support/Process.h"
33 #include "llvm/Support/Program.h"
34 #include "llvm/Support/raw_ostream.h"
35 #include "llvm/WindowsManifest/WindowsManifestMerger.h"
36 #include <memory>
37
38 using namespace llvm::COFF;
39 using namespace llvm;
40 using llvm::sys::Process;
41
42 namespace lld {
43 namespace coff {
44 namespace {
45
46 const uint16_t SUBLANG_ENGLISH_US = 0x0409;
47 const uint16_t RT_MANIFEST = 24;
48
49 class Executor {
50 public:
Executor(StringRef S)51 explicit Executor(StringRef S) : Prog(Saver.save(S)) {}
add(StringRef S)52 void add(StringRef S) { Args.push_back(Saver.save(S)); }
add(std::string & S)53 void add(std::string &S) { Args.push_back(Saver.save(S)); }
add(Twine S)54 void add(Twine S) { Args.push_back(Saver.save(S)); }
add(const char * S)55 void add(const char *S) { Args.push_back(Saver.save(S)); }
56
run()57 void run() {
58 ErrorOr<std::string> ExeOrErr = sys::findProgramByName(Prog);
59 if (auto EC = ExeOrErr.getError())
60 fatal("unable to find " + Prog + " in PATH: " + EC.message());
61 StringRef Exe = Saver.save(*ExeOrErr);
62 Args.insert(Args.begin(), Exe);
63
64 if (sys::ExecuteAndWait(Args[0], Args) != 0)
65 fatal("ExecuteAndWait failed: " +
66 llvm::join(Args.begin(), Args.end(), " "));
67 }
68
69 private:
70 StringRef Prog;
71 std::vector<StringRef> Args;
72 };
73
74 } // anonymous namespace
75
76 // Returns /machine's value.
getMachineType(StringRef S)77 MachineTypes getMachineType(StringRef S) {
78 MachineTypes MT = StringSwitch<MachineTypes>(S.lower())
79 .Cases("x64", "amd64", AMD64)
80 .Cases("x86", "i386", I386)
81 .Case("arm", ARMNT)
82 .Case("arm64", ARM64)
83 .Default(IMAGE_FILE_MACHINE_UNKNOWN);
84 if (MT != IMAGE_FILE_MACHINE_UNKNOWN)
85 return MT;
86 fatal("unknown /machine argument: " + S);
87 }
88
machineToStr(MachineTypes MT)89 StringRef machineToStr(MachineTypes MT) {
90 switch (MT) {
91 case ARMNT:
92 return "arm";
93 case ARM64:
94 return "arm64";
95 case AMD64:
96 return "x64";
97 case I386:
98 return "x86";
99 default:
100 llvm_unreachable("unknown machine type");
101 }
102 }
103
104 // Parses a string in the form of "<integer>[,<integer>]".
parseNumbers(StringRef Arg,uint64_t * Addr,uint64_t * Size)105 void parseNumbers(StringRef Arg, uint64_t *Addr, uint64_t *Size) {
106 StringRef S1, S2;
107 std::tie(S1, S2) = Arg.split(',');
108 if (S1.getAsInteger(0, *Addr))
109 fatal("invalid number: " + S1);
110 if (Size && !S2.empty() && S2.getAsInteger(0, *Size))
111 fatal("invalid number: " + S2);
112 }
113
114 // Parses a string in the form of "<integer>[.<integer>]".
115 // If second number is not present, Minor is set to 0.
parseVersion(StringRef Arg,uint32_t * Major,uint32_t * Minor)116 void parseVersion(StringRef Arg, uint32_t *Major, uint32_t *Minor) {
117 StringRef S1, S2;
118 std::tie(S1, S2) = Arg.split('.');
119 if (S1.getAsInteger(0, *Major))
120 fatal("invalid number: " + S1);
121 *Minor = 0;
122 if (!S2.empty() && S2.getAsInteger(0, *Minor))
123 fatal("invalid number: " + S2);
124 }
125
parseGuard(StringRef FullArg)126 void parseGuard(StringRef FullArg) {
127 SmallVector<StringRef, 1> SplitArgs;
128 FullArg.split(SplitArgs, ",");
129 for (StringRef Arg : SplitArgs) {
130 if (Arg.equals_lower("no"))
131 Config->GuardCF = GuardCFLevel::Off;
132 else if (Arg.equals_lower("nolongjmp"))
133 Config->GuardCF = GuardCFLevel::NoLongJmp;
134 else if (Arg.equals_lower("cf") || Arg.equals_lower("longjmp"))
135 Config->GuardCF = GuardCFLevel::Full;
136 else
137 fatal("invalid argument to /guard: " + Arg);
138 }
139 }
140
141 // Parses a string in the form of "<subsystem>[,<integer>[.<integer>]]".
parseSubsystem(StringRef Arg,WindowsSubsystem * Sys,uint32_t * Major,uint32_t * Minor)142 void parseSubsystem(StringRef Arg, WindowsSubsystem *Sys, uint32_t *Major,
143 uint32_t *Minor) {
144 StringRef SysStr, Ver;
145 std::tie(SysStr, Ver) = Arg.split(',');
146 *Sys = StringSwitch<WindowsSubsystem>(SysStr.lower())
147 .Case("boot_application", IMAGE_SUBSYSTEM_WINDOWS_BOOT_APPLICATION)
148 .Case("console", IMAGE_SUBSYSTEM_WINDOWS_CUI)
149 .Case("efi_application", IMAGE_SUBSYSTEM_EFI_APPLICATION)
150 .Case("efi_boot_service_driver", IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER)
151 .Case("efi_rom", IMAGE_SUBSYSTEM_EFI_ROM)
152 .Case("efi_runtime_driver", IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER)
153 .Case("native", IMAGE_SUBSYSTEM_NATIVE)
154 .Case("posix", IMAGE_SUBSYSTEM_POSIX_CUI)
155 .Case("windows", IMAGE_SUBSYSTEM_WINDOWS_GUI)
156 .Default(IMAGE_SUBSYSTEM_UNKNOWN);
157 if (*Sys == IMAGE_SUBSYSTEM_UNKNOWN)
158 fatal("unknown subsystem: " + SysStr);
159 if (!Ver.empty())
160 parseVersion(Ver, Major, Minor);
161 }
162
163 // Parse a string of the form of "<from>=<to>".
164 // Results are directly written to Config.
parseAlternateName(StringRef S)165 void parseAlternateName(StringRef S) {
166 StringRef From, To;
167 std::tie(From, To) = S.split('=');
168 if (From.empty() || To.empty())
169 fatal("/alternatename: invalid argument: " + S);
170 auto It = Config->AlternateNames.find(From);
171 if (It != Config->AlternateNames.end() && It->second != To)
172 fatal("/alternatename: conflicts: " + S);
173 Config->AlternateNames.insert(It, std::make_pair(From, To));
174 }
175
176 // Parse a string of the form of "<from>=<to>".
177 // Results are directly written to Config.
parseMerge(StringRef S)178 void parseMerge(StringRef S) {
179 StringRef From, To;
180 std::tie(From, To) = S.split('=');
181 if (From.empty() || To.empty())
182 fatal("/merge: invalid argument: " + S);
183 if (From == ".rsrc" || To == ".rsrc")
184 fatal("/merge: cannot merge '.rsrc' with any section");
185 if (From == ".reloc" || To == ".reloc")
186 fatal("/merge: cannot merge '.reloc' with any section");
187 auto Pair = Config->Merge.insert(std::make_pair(From, To));
188 bool Inserted = Pair.second;
189 if (!Inserted) {
190 StringRef Existing = Pair.first->second;
191 if (Existing != To)
192 warn(S + ": already merged into " + Existing);
193 }
194 }
195
parseSectionAttributes(StringRef S)196 static uint32_t parseSectionAttributes(StringRef S) {
197 uint32_t Ret = 0;
198 for (char C : S.lower()) {
199 switch (C) {
200 case 'd':
201 Ret |= IMAGE_SCN_MEM_DISCARDABLE;
202 break;
203 case 'e':
204 Ret |= IMAGE_SCN_MEM_EXECUTE;
205 break;
206 case 'k':
207 Ret |= IMAGE_SCN_MEM_NOT_CACHED;
208 break;
209 case 'p':
210 Ret |= IMAGE_SCN_MEM_NOT_PAGED;
211 break;
212 case 'r':
213 Ret |= IMAGE_SCN_MEM_READ;
214 break;
215 case 's':
216 Ret |= IMAGE_SCN_MEM_SHARED;
217 break;
218 case 'w':
219 Ret |= IMAGE_SCN_MEM_WRITE;
220 break;
221 default:
222 fatal("/section: invalid argument: " + S);
223 }
224 }
225 return Ret;
226 }
227
228 // Parses /section option argument.
parseSection(StringRef S)229 void parseSection(StringRef S) {
230 StringRef Name, Attrs;
231 std::tie(Name, Attrs) = S.split(',');
232 if (Name.empty() || Attrs.empty())
233 fatal("/section: invalid argument: " + S);
234 Config->Section[Name] = parseSectionAttributes(Attrs);
235 }
236
237 // Parses /aligncomm option argument.
parseAligncomm(StringRef S)238 void parseAligncomm(StringRef S) {
239 StringRef Name, Align;
240 std::tie(Name, Align) = S.split(',');
241 if (Name.empty() || Align.empty()) {
242 error("/aligncomm: invalid argument: " + S);
243 return;
244 }
245 int V;
246 if (Align.getAsInteger(0, V)) {
247 error("/aligncomm: invalid argument: " + S);
248 return;
249 }
250 Config->AlignComm[Name] = std::max(Config->AlignComm[Name], 1 << V);
251 }
252
253 // Parses a string in the form of "EMBED[,=<integer>]|NO".
254 // Results are directly written to Config.
parseManifest(StringRef Arg)255 void parseManifest(StringRef Arg) {
256 if (Arg.equals_lower("no")) {
257 Config->Manifest = Configuration::No;
258 return;
259 }
260 if (!Arg.startswith_lower("embed"))
261 fatal("invalid option " + Arg);
262 Config->Manifest = Configuration::Embed;
263 Arg = Arg.substr(strlen("embed"));
264 if (Arg.empty())
265 return;
266 if (!Arg.startswith_lower(",id="))
267 fatal("invalid option " + Arg);
268 Arg = Arg.substr(strlen(",id="));
269 if (Arg.getAsInteger(0, Config->ManifestID))
270 fatal("invalid option " + Arg);
271 }
272
273 // Parses a string in the form of "level=<string>|uiAccess=<string>|NO".
274 // Results are directly written to Config.
parseManifestUAC(StringRef Arg)275 void parseManifestUAC(StringRef Arg) {
276 if (Arg.equals_lower("no")) {
277 Config->ManifestUAC = false;
278 return;
279 }
280 for (;;) {
281 Arg = Arg.ltrim();
282 if (Arg.empty())
283 return;
284 if (Arg.startswith_lower("level=")) {
285 Arg = Arg.substr(strlen("level="));
286 std::tie(Config->ManifestLevel, Arg) = Arg.split(" ");
287 continue;
288 }
289 if (Arg.startswith_lower("uiaccess=")) {
290 Arg = Arg.substr(strlen("uiaccess="));
291 std::tie(Config->ManifestUIAccess, Arg) = Arg.split(" ");
292 continue;
293 }
294 fatal("invalid option " + Arg);
295 }
296 }
297
298 // An RAII temporary file class that automatically removes a temporary file.
299 namespace {
300 class TemporaryFile {
301 public:
TemporaryFile(StringRef Prefix,StringRef Extn,StringRef Contents="")302 TemporaryFile(StringRef Prefix, StringRef Extn, StringRef Contents = "") {
303 SmallString<128> S;
304 if (auto EC = sys::fs::createTemporaryFile("lld-" + Prefix, Extn, S))
305 fatal("cannot create a temporary file: " + EC.message());
306 Path = S.str();
307
308 if (!Contents.empty()) {
309 std::error_code EC;
310 raw_fd_ostream OS(Path, EC, sys::fs::F_None);
311 if (EC)
312 fatal("failed to open " + Path + ": " + EC.message());
313 OS << Contents;
314 }
315 }
316
TemporaryFile(TemporaryFile && Obj)317 TemporaryFile(TemporaryFile &&Obj) {
318 std::swap(Path, Obj.Path);
319 }
320
~TemporaryFile()321 ~TemporaryFile() {
322 if (Path.empty())
323 return;
324 if (sys::fs::remove(Path))
325 fatal("failed to remove " + Path);
326 }
327
328 // Returns a memory buffer of this temporary file.
329 // Note that this function does not leave the file open,
330 // so it is safe to remove the file immediately after this function
331 // is called (you cannot remove an opened file on Windows.)
getMemoryBuffer()332 std::unique_ptr<MemoryBuffer> getMemoryBuffer() {
333 // IsVolatileSize=true forces MemoryBuffer to not use mmap().
334 return CHECK(MemoryBuffer::getFile(Path, /*FileSize=*/-1,
335 /*RequiresNullTerminator=*/false,
336 /*IsVolatileSize=*/true),
337 "could not open " + Path);
338 }
339
340 std::string Path;
341 };
342 }
343
createDefaultXml()344 static std::string createDefaultXml() {
345 std::string Ret;
346 raw_string_ostream OS(Ret);
347
348 // Emit the XML. Note that we do *not* verify that the XML attributes are
349 // syntactically correct. This is intentional for link.exe compatibility.
350 OS << "<?xml version=\"1.0\" standalone=\"yes\"?>\n"
351 << "<assembly xmlns=\"urn:schemas-microsoft-com:asm.v1\"\n"
352 << " manifestVersion=\"1.0\">\n";
353 if (Config->ManifestUAC) {
354 OS << " <trustInfo>\n"
355 << " <security>\n"
356 << " <requestedPrivileges>\n"
357 << " <requestedExecutionLevel level=" << Config->ManifestLevel
358 << " uiAccess=" << Config->ManifestUIAccess << "/>\n"
359 << " </requestedPrivileges>\n"
360 << " </security>\n"
361 << " </trustInfo>\n";
362 }
363 if (!Config->ManifestDependency.empty()) {
364 OS << " <dependency>\n"
365 << " <dependentAssembly>\n"
366 << " <assemblyIdentity " << Config->ManifestDependency << " />\n"
367 << " </dependentAssembly>\n"
368 << " </dependency>\n";
369 }
370 OS << "</assembly>\n";
371 return OS.str();
372 }
373
createManifestXmlWithInternalMt(StringRef DefaultXml)374 static std::string createManifestXmlWithInternalMt(StringRef DefaultXml) {
375 std::unique_ptr<MemoryBuffer> DefaultXmlCopy =
376 MemoryBuffer::getMemBufferCopy(DefaultXml);
377
378 windows_manifest::WindowsManifestMerger Merger;
379 if (auto E = Merger.merge(*DefaultXmlCopy.get()))
380 fatal("internal manifest tool failed on default xml: " +
381 toString(std::move(E)));
382
383 for (StringRef Filename : Config->ManifestInput) {
384 std::unique_ptr<MemoryBuffer> Manifest =
385 check(MemoryBuffer::getFile(Filename));
386 if (auto E = Merger.merge(*Manifest.get()))
387 fatal("internal manifest tool failed on file " + Filename + ": " +
388 toString(std::move(E)));
389 }
390
391 return Merger.getMergedManifest().get()->getBuffer();
392 }
393
createManifestXmlWithExternalMt(StringRef DefaultXml)394 static std::string createManifestXmlWithExternalMt(StringRef DefaultXml) {
395 // Create the default manifest file as a temporary file.
396 TemporaryFile Default("defaultxml", "manifest");
397 std::error_code EC;
398 raw_fd_ostream OS(Default.Path, EC, sys::fs::F_Text);
399 if (EC)
400 fatal("failed to open " + Default.Path + ": " + EC.message());
401 OS << DefaultXml;
402 OS.close();
403
404 // Merge user-supplied manifests if they are given. Since libxml2 is not
405 // enabled, we must shell out to Microsoft's mt.exe tool.
406 TemporaryFile User("user", "manifest");
407
408 Executor E("mt.exe");
409 E.add("/manifest");
410 E.add(Default.Path);
411 for (StringRef Filename : Config->ManifestInput) {
412 E.add("/manifest");
413 E.add(Filename);
414 }
415 E.add("/nologo");
416 E.add("/out:" + StringRef(User.Path));
417 E.run();
418
419 return CHECK(MemoryBuffer::getFile(User.Path), "could not open " + User.Path)
420 .get()
421 ->getBuffer();
422 }
423
createManifestXml()424 static std::string createManifestXml() {
425 std::string DefaultXml = createDefaultXml();
426 if (Config->ManifestInput.empty())
427 return DefaultXml;
428
429 if (windows_manifest::isAvailable())
430 return createManifestXmlWithInternalMt(DefaultXml);
431
432 return createManifestXmlWithExternalMt(DefaultXml);
433 }
434
435 static std::unique_ptr<WritableMemoryBuffer>
createMemoryBufferForManifestRes(size_t ManifestSize)436 createMemoryBufferForManifestRes(size_t ManifestSize) {
437 size_t ResSize = alignTo(
438 object::WIN_RES_MAGIC_SIZE + object::WIN_RES_NULL_ENTRY_SIZE +
439 sizeof(object::WinResHeaderPrefix) + sizeof(object::WinResIDs) +
440 sizeof(object::WinResHeaderSuffix) + ManifestSize,
441 object::WIN_RES_DATA_ALIGNMENT);
442 return WritableMemoryBuffer::getNewMemBuffer(ResSize, Config->OutputFile +
443 ".manifest.res");
444 }
445
writeResFileHeader(char * & Buf)446 static void writeResFileHeader(char *&Buf) {
447 memcpy(Buf, COFF::WinResMagic, sizeof(COFF::WinResMagic));
448 Buf += sizeof(COFF::WinResMagic);
449 memset(Buf, 0, object::WIN_RES_NULL_ENTRY_SIZE);
450 Buf += object::WIN_RES_NULL_ENTRY_SIZE;
451 }
452
writeResEntryHeader(char * & Buf,size_t ManifestSize)453 static void writeResEntryHeader(char *&Buf, size_t ManifestSize) {
454 // Write the prefix.
455 auto *Prefix = reinterpret_cast<object::WinResHeaderPrefix *>(Buf);
456 Prefix->DataSize = ManifestSize;
457 Prefix->HeaderSize = sizeof(object::WinResHeaderPrefix) +
458 sizeof(object::WinResIDs) +
459 sizeof(object::WinResHeaderSuffix);
460 Buf += sizeof(object::WinResHeaderPrefix);
461
462 // Write the Type/Name IDs.
463 auto *IDs = reinterpret_cast<object::WinResIDs *>(Buf);
464 IDs->setType(RT_MANIFEST);
465 IDs->setName(Config->ManifestID);
466 Buf += sizeof(object::WinResIDs);
467
468 // Write the suffix.
469 auto *Suffix = reinterpret_cast<object::WinResHeaderSuffix *>(Buf);
470 Suffix->DataVersion = 0;
471 Suffix->MemoryFlags = object::WIN_RES_PURE_MOVEABLE;
472 Suffix->Language = SUBLANG_ENGLISH_US;
473 Suffix->Version = 0;
474 Suffix->Characteristics = 0;
475 Buf += sizeof(object::WinResHeaderSuffix);
476 }
477
478 // Create a resource file containing a manifest XML.
createManifestRes()479 std::unique_ptr<MemoryBuffer> createManifestRes() {
480 std::string Manifest = createManifestXml();
481
482 std::unique_ptr<WritableMemoryBuffer> Res =
483 createMemoryBufferForManifestRes(Manifest.size());
484
485 char *Buf = Res->getBufferStart();
486 writeResFileHeader(Buf);
487 writeResEntryHeader(Buf, Manifest.size());
488
489 // Copy the manifest data into the .res file.
490 std::copy(Manifest.begin(), Manifest.end(), Buf);
491 return std::move(Res);
492 }
493
createSideBySideManifest()494 void createSideBySideManifest() {
495 std::string Path = Config->ManifestFile;
496 if (Path == "")
497 Path = Config->OutputFile + ".manifest";
498 std::error_code EC;
499 raw_fd_ostream Out(Path, EC, sys::fs::F_Text);
500 if (EC)
501 fatal("failed to create manifest: " + EC.message());
502 Out << createManifestXml();
503 }
504
505 // Parse a string in the form of
506 // "<name>[=<internalname>][,@ordinal[,NONAME]][,DATA][,PRIVATE]"
507 // or "<name>=<dllname>.<name>".
508 // Used for parsing /export arguments.
parseExport(StringRef Arg)509 Export parseExport(StringRef Arg) {
510 Export E;
511 StringRef Rest;
512 std::tie(E.Name, Rest) = Arg.split(",");
513 if (E.Name.empty())
514 goto err;
515
516 if (E.Name.contains('=')) {
517 StringRef X, Y;
518 std::tie(X, Y) = E.Name.split("=");
519
520 // If "<name>=<dllname>.<name>".
521 if (Y.contains(".")) {
522 E.Name = X;
523 E.ForwardTo = Y;
524 return E;
525 }
526
527 E.ExtName = X;
528 E.Name = Y;
529 if (E.Name.empty())
530 goto err;
531 }
532
533 // If "<name>=<internalname>[,@ordinal[,NONAME]][,DATA][,PRIVATE]"
534 while (!Rest.empty()) {
535 StringRef Tok;
536 std::tie(Tok, Rest) = Rest.split(",");
537 if (Tok.equals_lower("noname")) {
538 if (E.Ordinal == 0)
539 goto err;
540 E.Noname = true;
541 continue;
542 }
543 if (Tok.equals_lower("data")) {
544 E.Data = true;
545 continue;
546 }
547 if (Tok.equals_lower("constant")) {
548 E.Constant = true;
549 continue;
550 }
551 if (Tok.equals_lower("private")) {
552 E.Private = true;
553 continue;
554 }
555 if (Tok.startswith("@")) {
556 int32_t Ord;
557 if (Tok.substr(1).getAsInteger(0, Ord))
558 goto err;
559 if (Ord <= 0 || 65535 < Ord)
560 goto err;
561 E.Ordinal = Ord;
562 continue;
563 }
564 goto err;
565 }
566 return E;
567
568 err:
569 fatal("invalid /export: " + Arg);
570 }
571
undecorate(StringRef Sym)572 static StringRef undecorate(StringRef Sym) {
573 if (Config->Machine != I386)
574 return Sym;
575 // In MSVC mode, a fully decorated stdcall function is exported
576 // as-is with the leading underscore (with type IMPORT_NAME).
577 // In MinGW mode, a decorated stdcall function gets the underscore
578 // removed, just like normal cdecl functions.
579 if (Sym.startswith("_") && Sym.contains('@') && !Config->MinGW)
580 return Sym;
581 return Sym.startswith("_") ? Sym.substr(1) : Sym;
582 }
583
584 // Convert stdcall/fastcall style symbols into unsuffixed symbols,
585 // with or without a leading underscore. (MinGW specific.)
killAt(StringRef Sym,bool Prefix)586 static StringRef killAt(StringRef Sym, bool Prefix) {
587 if (Sym.empty())
588 return Sym;
589 // Strip any trailing stdcall suffix
590 Sym = Sym.substr(0, Sym.find('@', 1));
591 if (!Sym.startswith("@")) {
592 if (Prefix && !Sym.startswith("_"))
593 return Saver.save("_" + Sym);
594 return Sym;
595 }
596 // For fastcall, remove the leading @ and replace it with an
597 // underscore, if prefixes are used.
598 Sym = Sym.substr(1);
599 if (Prefix)
600 Sym = Saver.save("_" + Sym);
601 return Sym;
602 }
603
604 // Performs error checking on all /export arguments.
605 // It also sets ordinals.
fixupExports()606 void fixupExports() {
607 // Symbol ordinals must be unique.
608 std::set<uint16_t> Ords;
609 for (Export &E : Config->Exports) {
610 if (E.Ordinal == 0)
611 continue;
612 if (!Ords.insert(E.Ordinal).second)
613 fatal("duplicate export ordinal: " + E.Name);
614 }
615
616 for (Export &E : Config->Exports) {
617 Symbol *Sym = E.Sym;
618 if (!E.ForwardTo.empty() || !Sym) {
619 E.SymbolName = E.Name;
620 } else {
621 if (auto *U = dyn_cast<Undefined>(Sym))
622 if (U->WeakAlias)
623 Sym = U->WeakAlias;
624 E.SymbolName = Sym->getName();
625 }
626 }
627
628 for (Export &E : Config->Exports) {
629 if (!E.ForwardTo.empty()) {
630 E.ExportName = undecorate(E.Name);
631 } else {
632 E.ExportName = undecorate(E.ExtName.empty() ? E.Name : E.ExtName);
633 }
634 }
635
636 if (Config->KillAt && Config->Machine == I386) {
637 for (Export &E : Config->Exports) {
638 E.Name = killAt(E.Name, true);
639 E.ExportName = killAt(E.ExportName, false);
640 E.ExtName = killAt(E.ExtName, true);
641 E.SymbolName = killAt(E.SymbolName, true);
642 }
643 }
644
645 // Uniquefy by name.
646 DenseMap<StringRef, Export *> Map(Config->Exports.size());
647 std::vector<Export> V;
648 for (Export &E : Config->Exports) {
649 auto Pair = Map.insert(std::make_pair(E.ExportName, &E));
650 bool Inserted = Pair.second;
651 if (Inserted) {
652 V.push_back(E);
653 continue;
654 }
655 Export *Existing = Pair.first->second;
656 if (E == *Existing || E.Name != Existing->Name)
657 continue;
658 warn("duplicate /export option: " + E.Name);
659 }
660 Config->Exports = std::move(V);
661
662 // Sort by name.
663 std::sort(Config->Exports.begin(), Config->Exports.end(),
664 [](const Export &A, const Export &B) {
665 return A.ExportName < B.ExportName;
666 });
667 }
668
assignExportOrdinals()669 void assignExportOrdinals() {
670 // Assign unique ordinals if default (= 0).
671 uint16_t Max = 0;
672 for (Export &E : Config->Exports)
673 Max = std::max(Max, E.Ordinal);
674 for (Export &E : Config->Exports)
675 if (E.Ordinal == 0)
676 E.Ordinal = ++Max;
677 }
678
679 // Parses a string in the form of "key=value" and check
680 // if value matches previous values for the same key.
checkFailIfMismatch(StringRef Arg)681 void checkFailIfMismatch(StringRef Arg) {
682 StringRef K, V;
683 std::tie(K, V) = Arg.split('=');
684 if (K.empty() || V.empty())
685 fatal("/failifmismatch: invalid argument: " + Arg);
686 StringRef Existing = Config->MustMatch[K];
687 if (!Existing.empty() && V != Existing)
688 fatal("/failifmismatch: mismatch detected: " + Existing + " and " + V +
689 " for key " + K);
690 Config->MustMatch[K] = V;
691 }
692
693 // Convert Windows resource files (.res files) to a .obj file.
convertResToCOFF(ArrayRef<MemoryBufferRef> MBs)694 MemoryBufferRef convertResToCOFF(ArrayRef<MemoryBufferRef> MBs) {
695 object::WindowsResourceParser Parser;
696
697 for (MemoryBufferRef MB : MBs) {
698 std::unique_ptr<object::Binary> Bin = check(object::createBinary(MB));
699 object::WindowsResource *RF = dyn_cast<object::WindowsResource>(Bin.get());
700 if (!RF)
701 fatal("cannot compile non-resource file as resource");
702 if (auto EC = Parser.parse(RF))
703 fatal("failed to parse .res file: " + toString(std::move(EC)));
704 }
705
706 Expected<std::unique_ptr<MemoryBuffer>> E =
707 llvm::object::writeWindowsResourceCOFF(Config->Machine, Parser);
708 if (!E)
709 fatal("failed to write .res to COFF: " + toString(E.takeError()));
710
711 MemoryBufferRef MBRef = **E;
712 make<std::unique_ptr<MemoryBuffer>>(std::move(*E)); // take ownership
713 return MBRef;
714 }
715
716 // Create OptTable
717
718 // Create prefix string literals used in Options.td
719 #define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
720 #include "Options.inc"
721 #undef PREFIX
722
723 // Create table mapping all options defined in Options.td
724 static const llvm::opt::OptTable::Info InfoTable[] = {
725 #define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X7, X8, X9, X10, X11, X12) \
726 {X1, X2, X10, X11, OPT_##ID, llvm::opt::Option::KIND##Class, \
727 X9, X8, OPT_##GROUP, OPT_##ALIAS, X7, X12},
728 #include "Options.inc"
729 #undef OPTION
730 };
731
COFFOptTable()732 COFFOptTable::COFFOptTable() : OptTable(InfoTable, true) {}
733
734 // Set color diagnostics according to --color-diagnostics={auto,always,never}
735 // or --no-color-diagnostics flags.
handleColorDiagnostics(opt::InputArgList & Args)736 static void handleColorDiagnostics(opt::InputArgList &Args) {
737 auto *Arg = Args.getLastArg(OPT_color_diagnostics, OPT_color_diagnostics_eq,
738 OPT_no_color_diagnostics);
739 if (!Arg)
740 return;
741 if (Arg->getOption().getID() == OPT_color_diagnostics) {
742 errorHandler().ColorDiagnostics = true;
743 } else if (Arg->getOption().getID() == OPT_no_color_diagnostics) {
744 errorHandler().ColorDiagnostics = false;
745 } else {
746 StringRef S = Arg->getValue();
747 if (S == "always")
748 errorHandler().ColorDiagnostics = true;
749 else if (S == "never")
750 errorHandler().ColorDiagnostics = false;
751 else if (S != "auto")
752 error("unknown option: --color-diagnostics=" + S);
753 }
754 }
755
getQuotingStyle(opt::InputArgList & Args)756 static cl::TokenizerCallback getQuotingStyle(opt::InputArgList &Args) {
757 if (auto *Arg = Args.getLastArg(OPT_rsp_quoting)) {
758 StringRef S = Arg->getValue();
759 if (S != "windows" && S != "posix")
760 error("invalid response file quoting: " + S);
761 if (S == "windows")
762 return cl::TokenizeWindowsCommandLine;
763 return cl::TokenizeGNUCommandLine;
764 }
765 // The COFF linker always defaults to Windows quoting.
766 return cl::TokenizeWindowsCommandLine;
767 }
768
769 // Parses a given list of options.
parse(ArrayRef<const char * > Argv)770 opt::InputArgList ArgParser::parse(ArrayRef<const char *> Argv) {
771 // Make InputArgList from string vectors.
772 unsigned MissingIndex;
773 unsigned MissingCount;
774
775 // We need to get the quoting style for response files before parsing all
776 // options so we parse here before and ignore all the options but
777 // --rsp-quoting.
778 opt::InputArgList Args = Table.ParseArgs(Argv, MissingIndex, MissingCount);
779
780 // Expand response files (arguments in the form of @<filename>)
781 // and then parse the argument again.
782 SmallVector<const char *, 256> ExpandedArgv(Argv.data(), Argv.data() + Argv.size());
783 cl::ExpandResponseFiles(Saver, getQuotingStyle(Args), ExpandedArgv);
784 Args = Table.ParseArgs(makeArrayRef(ExpandedArgv).drop_front(), MissingIndex,
785 MissingCount);
786
787 // Print the real command line if response files are expanded.
788 if (Args.hasArg(OPT_verbose) && Argv.size() != ExpandedArgv.size()) {
789 std::string Msg = "Command line:";
790 for (const char *S : ExpandedArgv)
791 Msg += " " + std::string(S);
792 message(Msg);
793 }
794
795 // Save the command line after response file expansion so we can write it to
796 // the PDB if necessary.
797 Config->Argv = {ExpandedArgv.begin(), ExpandedArgv.end()};
798
799 // Handle /WX early since it converts missing argument warnings to errors.
800 errorHandler().FatalWarnings = Args.hasFlag(OPT_WX, OPT_WX_no, false);
801
802 if (MissingCount)
803 fatal(Twine(Args.getArgString(MissingIndex)) + ": missing argument");
804
805 handleColorDiagnostics(Args);
806
807 for (auto *Arg : Args.filtered(OPT_UNKNOWN))
808 warn("ignoring unknown argument: " + Arg->getSpelling());
809
810 if (Args.hasArg(OPT_lib))
811 warn("ignoring /lib since it's not the first argument");
812
813 return Args;
814 }
815
816 // Tokenizes and parses a given string as command line in .drective section.
817 // /EXPORT options are processed in fastpath.
818 std::pair<opt::InputArgList, std::vector<StringRef>>
parseDirectives(StringRef S)819 ArgParser::parseDirectives(StringRef S) {
820 std::vector<StringRef> Exports;
821 SmallVector<const char *, 16> Rest;
822
823 for (StringRef Tok : tokenize(S)) {
824 if (Tok.startswith_lower("/export:") || Tok.startswith_lower("-export:"))
825 Exports.push_back(Tok.substr(strlen("/export:")));
826 else
827 Rest.push_back(Tok.data());
828 }
829
830 // Make InputArgList from unparsed string vectors.
831 unsigned MissingIndex;
832 unsigned MissingCount;
833
834 opt::InputArgList Args = Table.ParseArgs(Rest, MissingIndex, MissingCount);
835
836 if (MissingCount)
837 fatal(Twine(Args.getArgString(MissingIndex)) + ": missing argument");
838 for (auto *Arg : Args.filtered(OPT_UNKNOWN))
839 warn("ignoring unknown argument: " + Arg->getSpelling());
840 return {std::move(Args), std::move(Exports)};
841 }
842
843 // link.exe has an interesting feature. If LINK or _LINK_ environment
844 // variables exist, their contents are handled as command line strings.
845 // So you can pass extra arguments using them.
parseLINK(std::vector<const char * > Argv)846 opt::InputArgList ArgParser::parseLINK(std::vector<const char *> Argv) {
847 // Concatenate LINK env and command line arguments, and then parse them.
848 if (Optional<std::string> S = Process::GetEnv("LINK")) {
849 std::vector<const char *> V = tokenize(*S);
850 Argv.insert(std::next(Argv.begin()), V.begin(), V.end());
851 }
852 if (Optional<std::string> S = Process::GetEnv("_LINK_")) {
853 std::vector<const char *> V = tokenize(*S);
854 Argv.insert(std::next(Argv.begin()), V.begin(), V.end());
855 }
856 return parse(Argv);
857 }
858
tokenize(StringRef S)859 std::vector<const char *> ArgParser::tokenize(StringRef S) {
860 SmallVector<const char *, 16> Tokens;
861 cl::TokenizeWindowsCommandLine(S, Saver, Tokens);
862 return std::vector<const char *>(Tokens.begin(), Tokens.end());
863 }
864
printHelp(const char * Argv0)865 void printHelp(const char *Argv0) {
866 COFFOptTable().PrintHelp(outs(),
867 (std::string(Argv0) + " [options] file...").c_str(),
868 "LLVM Linker", false);
869 }
870
871 } // namespace coff
872 } // namespace lld
873