//===- DriverUtils.cpp ----------------------------------------------------===//
//
// The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains utility functions for the driver. Because there
// are so many small functions, we created this separate file to make
// Driver.cpp less cluttered.
//
//===----------------------------------------------------------------------===//
#include "Config.h"
#include "Driver.h"
#include "Error.h"
#include "Memory.h"
#include "Symbols.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/Object/COFF.h"
#include "llvm/Option/Arg.h"
#include "llvm/Option/ArgList.h"
#include "llvm/Option/Option.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/Support/Process.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/raw_ostream.h"
#include <memory>
using namespace llvm::COFF;
using namespace llvm;
using llvm::cl::ExpandResponseFiles;
using llvm::cl::TokenizeWindowsCommandLine;
using llvm::sys::Process;
namespace lld {
namespace coff {
namespace {
class Executor {
public:
explicit Executor(StringRef S) : Saver(Alloc), Prog(Saver.save(S)) {}
void add(StringRef S) { Args.push_back(Saver.save(S)); }
void add(std::string &S) { Args.push_back(Saver.save(S)); }
void add(Twine S) { Args.push_back(Saver.save(S)); }
void add(const char *S) { Args.push_back(Saver.save(S)); }
void run() {
ErrorOr<std::string> ExeOrErr = sys::findProgramByName(Prog);
if (auto EC = ExeOrErr.getError())
fatal(EC, "unable to find " + Prog + " in PATH: ");
StringRef Exe = Saver.save(*ExeOrErr);
Args.insert(Args.begin(), Exe);
std::vector<const char *> Vec;
for (StringRef S : Args)
Vec.push_back(S.data());
Vec.push_back(nullptr);
if (sys::ExecuteAndWait(Args[0], Vec.data()) != 0)
fatal("ExecuteAndWait failed: " +
llvm::join(Args.begin(), Args.end(), " "));
}
private:
BumpPtrAllocator Alloc;
StringSaver Saver;
StringRef Prog;
std::vector<StringRef> Args;
};
} // anonymous namespace
// Returns /machine's value.
MachineTypes getMachineType(StringRef S) {
MachineTypes MT = StringSwitch<MachineTypes>(S.lower())
.Cases("x64", "amd64", AMD64)
.Cases("x86", "i386", I386)
.Case("arm", ARMNT)
.Default(IMAGE_FILE_MACHINE_UNKNOWN);
if (MT != IMAGE_FILE_MACHINE_UNKNOWN)
return MT;
fatal("unknown /machine argument: " + S);
}
StringRef machineToStr(MachineTypes MT) {
switch (MT) {
case ARMNT:
return "arm";
case AMD64:
return "x64";
case I386:
return "x86";
default:
llvm_unreachable("unknown machine type");
}
}
// Parses a string in the form of "<integer>[,<integer>]".
void parseNumbers(StringRef Arg, uint64_t *Addr, uint64_t *Size) {
StringRef S1, S2;
std::tie(S1, S2) = Arg.split(',');
if (S1.getAsInteger(0, *Addr))
fatal("invalid number: " + S1);
if (Size && !S2.empty() && S2.getAsInteger(0, *Size))
fatal("invalid number: " + S2);
}
// Parses a string in the form of "<integer>[.<integer>]".
// If second number is not present, Minor is set to 0.
void parseVersion(StringRef Arg, uint32_t *Major, uint32_t *Minor) {
StringRef S1, S2;
std::tie(S1, S2) = Arg.split('.');
if (S1.getAsInteger(0, *Major))
fatal("invalid number: " + S1);
*Minor = 0;
if (!S2.empty() && S2.getAsInteger(0, *Minor))
fatal("invalid number: " + S2);
}
// Parses a string in the form of "<subsystem>[,<integer>[.<integer>]]".
void parseSubsystem(StringRef Arg, WindowsSubsystem *Sys, uint32_t *Major,
uint32_t *Minor) {
StringRef SysStr, Ver;
std::tie(SysStr, Ver) = Arg.split(',');
*Sys = StringSwitch<WindowsSubsystem>(SysStr.lower())
.Case("boot_application", IMAGE_SUBSYSTEM_WINDOWS_BOOT_APPLICATION)
.Case("console", IMAGE_SUBSYSTEM_WINDOWS_CUI)
.Case("efi_application", IMAGE_SUBSYSTEM_EFI_APPLICATION)
.Case("efi_boot_service_driver", IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER)
.Case("efi_rom", IMAGE_SUBSYSTEM_EFI_ROM)
.Case("efi_runtime_driver", IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER)
.Case("native", IMAGE_SUBSYSTEM_NATIVE)
.Case("posix", IMAGE_SUBSYSTEM_POSIX_CUI)
.Case("windows", IMAGE_SUBSYSTEM_WINDOWS_GUI)
.Default(IMAGE_SUBSYSTEM_UNKNOWN);
if (*Sys == IMAGE_SUBSYSTEM_UNKNOWN)
fatal("unknown subsystem: " + SysStr);
if (!Ver.empty())
parseVersion(Ver, Major, Minor);
}
// Parse a string of the form of "<from>=<to>".
// Results are directly written to Config.
void parseAlternateName(StringRef S) {
StringRef From, To;
std::tie(From, To) = S.split('=');
if (From.empty() || To.empty())
fatal("/alternatename: invalid argument: " + S);
auto It = Config->AlternateNames.find(From);
if (It != Config->AlternateNames.end() && It->second != To)
fatal("/alternatename: conflicts: " + S);
Config->AlternateNames.insert(It, std::make_pair(From, To));
}
// Parse a string of the form of "<from>=<to>".
// Results are directly written to Config.
void parseMerge(StringRef S) {
StringRef From, To;
std::tie(From, To) = S.split('=');
if (From.empty() || To.empty())
fatal("/merge: invalid argument: " + S);
auto Pair = Config->Merge.insert(std::make_pair(From, To));
bool Inserted = Pair.second;
if (!Inserted) {
StringRef Existing = Pair.first->second;
if (Existing != To)
warn(S + ": already merged into " + Existing);
}
}
static uint32_t parseSectionAttributes(StringRef S) {
uint32_t Ret = 0;
for (char C : S.lower()) {
switch (C) {
case 'd':
Ret |= IMAGE_SCN_MEM_DISCARDABLE;
break;
case 'e':
Ret |= IMAGE_SCN_MEM_EXECUTE;
break;
case 'k':
Ret |= IMAGE_SCN_MEM_NOT_CACHED;
break;
case 'p':
Ret |= IMAGE_SCN_MEM_NOT_PAGED;
break;
case 'r':
Ret |= IMAGE_SCN_MEM_READ;
break;
case 's':
Ret |= IMAGE_SCN_MEM_SHARED;
break;
case 'w':
Ret |= IMAGE_SCN_MEM_WRITE;
break;
default:
fatal("/section: invalid argument: " + S);
}
}
return Ret;
}
// Parses /section option argument.
void parseSection(StringRef S) {
StringRef Name, Attrs;
std::tie(Name, Attrs) = S.split(',');
if (Name.empty() || Attrs.empty())
fatal("/section: invalid argument: " + S);
Config->Section[Name] = parseSectionAttributes(Attrs);
}
// Parses a string in the form of "EMBED[,=<integer>]|NO".
// Results are directly written to Config.
void parseManifest(StringRef Arg) {
if (Arg.equals_lower("no")) {
Config->Manifest = Configuration::No;
return;
}
if (!Arg.startswith_lower("embed"))
fatal("invalid option " + Arg);
Config->Manifest = Configuration::Embed;
Arg = Arg.substr(strlen("embed"));
if (Arg.empty())
return;
if (!Arg.startswith_lower(",id="))
fatal("invalid option " + Arg);
Arg = Arg.substr(strlen(",id="));
if (Arg.getAsInteger(0, Config->ManifestID))
fatal("invalid option " + Arg);
}
// Parses a string in the form of "level=<string>|uiAccess=<string>|NO".
// Results are directly written to Config.
void parseManifestUAC(StringRef Arg) {
if (Arg.equals_lower("no")) {
Config->ManifestUAC = false;
return;
}
for (;;) {
Arg = Arg.ltrim();
if (Arg.empty())
return;
if (Arg.startswith_lower("level=")) {
Arg = Arg.substr(strlen("level="));
std::tie(Config->ManifestLevel, Arg) = Arg.split(" ");
continue;
}
if (Arg.startswith_lower("uiaccess=")) {
Arg = Arg.substr(strlen("uiaccess="));
std::tie(Config->ManifestUIAccess, Arg) = Arg.split(" ");
continue;
}
fatal("invalid option " + Arg);
}
}
// Quote each line with "". Existing double-quote is converted
// to two double-quotes.
static void quoteAndPrint(raw_ostream &Out, StringRef S) {
while (!S.empty()) {
StringRef Line;
std::tie(Line, S) = S.split("\n");
if (Line.empty())
continue;
Out << '\"';
for (int I = 0, E = Line.size(); I != E; ++I) {
if (Line[I] == '\"') {
Out << "\"\"";
} else {
Out << Line[I];
}
}
Out << "\"\n";
}
}
// An RAII temporary file class that automatically removes a temporary file.
namespace {
class TemporaryFile {
public:
TemporaryFile(StringRef Prefix, StringRef Extn, StringRef Contents = "") {
SmallString<128> S;
if (auto EC = sys::fs::createTemporaryFile("lld-" + Prefix, Extn, S))
fatal(EC, "cannot create a temporary file");
Path = S.str();
if (!Contents.empty()) {
std::error_code EC;
raw_fd_ostream OS(Path, EC, sys::fs::F_None);
if (EC)
fatal(EC, "failed to open " + Path);
OS << Contents;
}
}
TemporaryFile(TemporaryFile &&Obj) {
std::swap(Path, Obj.Path);
}
~TemporaryFile() {
if (Path.empty())
return;
if (sys::fs::remove(Path))
fatal("failed to remove " + Path);
}
// Returns a memory buffer of this temporary file.
// Note that this function does not leave the file open,
// so it is safe to remove the file immediately after this function
// is called (you cannot remove an opened file on Windows.)
std::unique_ptr<MemoryBuffer> getMemoryBuffer() {
// IsVolatileSize=true forces MemoryBuffer to not use mmap().
return check(MemoryBuffer::getFile(Path, /*FileSize=*/-1,
/*RequiresNullTerminator=*/false,
/*IsVolatileSize=*/true),
"could not open " + Path);
}
std::string Path;
};
}
// Create the default manifest file as a temporary file.
TemporaryFile createDefaultXml() {
// Create a temporary file.
TemporaryFile File("defaultxml", "manifest");
// Open the temporary file for writing.
std::error_code EC;
raw_fd_ostream OS(File.Path, EC, sys::fs::F_Text);
if (EC)
fatal(EC, "failed to open " + File.Path);
// Emit the XML. Note that we do *not* verify that the XML attributes are
// syntactically correct. This is intentional for link.exe compatibility.
OS << "<?xml version=\"1.0\" standalone=\"yes\"?>\n"
<< "<assembly xmlns=\"urn:schemas-microsoft-com:asm.v1\"\n"
<< " manifestVersion=\"1.0\">\n";
if (Config->ManifestUAC) {
OS << " <trustInfo>\n"
<< " <security>\n"
<< " <requestedPrivileges>\n"
<< " <requestedExecutionLevel level=" << Config->ManifestLevel
<< " uiAccess=" << Config->ManifestUIAccess << "/>\n"
<< " </requestedPrivileges>\n"
<< " </security>\n"
<< " </trustInfo>\n";
if (!Config->ManifestDependency.empty()) {
OS << " <dependency>\n"
<< " <dependentAssembly>\n"
<< " <assemblyIdentity " << Config->ManifestDependency << " />\n"
<< " </dependentAssembly>\n"
<< " </dependency>\n";
}
}
OS << "</assembly>\n";
OS.close();
return File;
}
static std::string readFile(StringRef Path) {
std::unique_ptr<MemoryBuffer> MB =
check(MemoryBuffer::getFile(Path), "could not open " + Path);
return MB->getBuffer();
}
static std::string createManifestXml() {
// Create the default manifest file.
TemporaryFile File1 = createDefaultXml();
if (Config->ManifestInput.empty())
return readFile(File1.Path);
// If manifest files are supplied by the user using /MANIFESTINPUT
// option, we need to merge them with the default manifest.
TemporaryFile File2("user", "manifest");
Executor E("mt.exe");
E.add("/manifest");
E.add(File1.Path);
for (StringRef Filename : Config->ManifestInput) {
E.add("/manifest");
E.add(Filename);
}
E.add("/nologo");
E.add("/out:" + StringRef(File2.Path));
E.run();
return readFile(File2.Path);
}
// Create a resource file containing a manifest XML.
std::unique_ptr<MemoryBuffer> createManifestRes() {
// Create a temporary file for the resource script file.
TemporaryFile RCFile("manifest", "rc");
// Open the temporary file for writing.
std::error_code EC;
raw_fd_ostream Out(RCFile.Path, EC, sys::fs::F_Text);
if (EC)
fatal(EC, "failed to open " + RCFile.Path);
// Write resource script to the RC file.
Out << "#define LANG_ENGLISH 9\n"
<< "#define SUBLANG_DEFAULT 1\n"
<< "#define APP_MANIFEST " << Config->ManifestID << "\n"
<< "#define RT_MANIFEST 24\n"
<< "LANGUAGE LANG_ENGLISH, SUBLANG_DEFAULT\n"
<< "APP_MANIFEST RT_MANIFEST {\n";
quoteAndPrint(Out, createManifestXml());
Out << "}\n";
Out.close();
// Create output resource file.
TemporaryFile ResFile("output-resource", "res");
Executor E("rc.exe");
E.add("/fo");
E.add(ResFile.Path);
E.add("/nologo");
E.add(RCFile.Path);
E.run();
return ResFile.getMemoryBuffer();
}
void createSideBySideManifest() {
std::string Path = Config->ManifestFile;
if (Path == "")
Path = Config->OutputFile + ".manifest";
std::error_code EC;
raw_fd_ostream Out(Path, EC, sys::fs::F_Text);
if (EC)
fatal(EC, "failed to create manifest");
Out << createManifestXml();
}
// Parse a string in the form of
// "<name>[=<internalname>][,@ordinal[,NONAME]][,DATA][,PRIVATE]"
// or "<name>=<dllname>.<name>".
// Used for parsing /export arguments.
Export parseExport(StringRef Arg) {
Export E;
StringRef Rest;
std::tie(E.Name, Rest) = Arg.split(",");
if (E.Name.empty())
goto err;
if (E.Name.find('=') != StringRef::npos) {
StringRef X, Y;
std::tie(X, Y) = E.Name.split("=");
// If "<name>=<dllname>.<name>".
if (Y.find(".") != StringRef::npos) {
E.Name = X;
E.ForwardTo = Y;
return E;
}
E.ExtName = X;
E.Name = Y;
if (E.Name.empty())
goto err;
}
// If "<name>=<internalname>[,@ordinal[,NONAME]][,DATA][,PRIVATE]"
while (!Rest.empty()) {
StringRef Tok;
std::tie(Tok, Rest) = Rest.split(",");
if (Tok.equals_lower("noname")) {
if (E.Ordinal == 0)
goto err;
E.Noname = true;
continue;
}
if (Tok.equals_lower("data")) {
E.Data = true;
continue;
}
if (Tok.equals_lower("private")) {
E.Private = true;
continue;
}
if (Tok.startswith("@")) {
int32_t Ord;
if (Tok.substr(1).getAsInteger(0, Ord))
goto err;
if (Ord <= 0 || 65535 < Ord)
goto err;
E.Ordinal = Ord;
continue;
}
goto err;
}
return E;
err:
fatal("invalid /export: " + Arg);
}
static StringRef undecorate(StringRef Sym) {
if (Config->Machine != I386)
return Sym;
return Sym.startswith("_") ? Sym.substr(1) : Sym;
}
// Performs error checking on all /export arguments.
// It also sets ordinals.
void fixupExports() {
// Symbol ordinals must be unique.
std::set<uint16_t> Ords;
for (Export &E : Config->Exports) {
if (E.Ordinal == 0)
continue;
if (!Ords.insert(E.Ordinal).second)
fatal("duplicate export ordinal: " + E.Name);
}
for (Export &E : Config->Exports) {
SymbolBody *Sym = E.Sym;
if (!E.ForwardTo.empty()) {
E.SymbolName = E.Name;
} else {
if (auto *U = dyn_cast<Undefined>(Sym))
if (U->WeakAlias)
Sym = U->WeakAlias;
E.SymbolName = Sym->getName();
}
}
for (Export &E : Config->Exports) {
if (!E.ForwardTo.empty()) {
E.ExportName = undecorate(E.Name);
} else {
E.ExportName = undecorate(E.ExtName.empty() ? E.Name : E.ExtName);
}
}
// Uniquefy by name.
std::map<StringRef, Export *> Map;
std::vector<Export> V;
for (Export &E : Config->Exports) {
auto Pair = Map.insert(std::make_pair(E.ExportName, &E));
bool Inserted = Pair.second;
if (Inserted) {
V.push_back(E);
continue;
}
Export *Existing = Pair.first->second;
if (E == *Existing || E.Name != Existing->Name)
continue;
warn("duplicate /export option: " + E.Name);
}
Config->Exports = std::move(V);
// Sort by name.
std::sort(Config->Exports.begin(), Config->Exports.end(),
[](const Export &A, const Export &B) {
return A.ExportName < B.ExportName;
});
}
void assignExportOrdinals() {
// Assign unique ordinals if default (= 0).
uint16_t Max = 0;
for (Export &E : Config->Exports)
Max = std::max(Max, E.Ordinal);
for (Export &E : Config->Exports)
if (E.Ordinal == 0)
E.Ordinal = ++Max;
}
// Parses a string in the form of "key=value" and check
// if value matches previous values for the same key.
void checkFailIfMismatch(StringRef Arg) {
StringRef K, V;
std::tie(K, V) = Arg.split('=');
if (K.empty() || V.empty())
fatal("/failifmismatch: invalid argument: " + Arg);
StringRef Existing = Config->MustMatch[K];
if (!Existing.empty() && V != Existing)
fatal("/failifmismatch: mismatch detected: " + Existing + " and " + V +
" for key " + K);
Config->MustMatch[K] = V;
}
// Convert Windows resource files (.res files) to a .obj file
// using cvtres.exe.
std::unique_ptr<MemoryBuffer>
convertResToCOFF(const std::vector<MemoryBufferRef> &MBs) {
// Create an output file path.
TemporaryFile File("resource-file", "obj");
// Execute cvtres.exe.
Executor E("cvtres.exe");
E.add("/machine:" + machineToStr(Config->Machine));
E.add("/readonly");
E.add("/nologo");
E.add("/out:" + Twine(File.Path));
// We must create new files because the memory buffers we have may have no
// underlying file still existing on the disk.
// It happens if it was created from a TemporaryFile, which usually delete
// the file just after creating the MemoryBuffer.
std::vector<TemporaryFile> ResFiles;
ResFiles.reserve(MBs.size());
for (MemoryBufferRef MB : MBs) {
// We store the temporary file in a vector to avoid deletion
// before running cvtres
ResFiles.emplace_back("resource-file", "res");
TemporaryFile& ResFile = ResFiles.back();
// Write the content of the resource in a temporary file
std::error_code EC;
raw_fd_ostream OS(ResFile.Path, EC, sys::fs::F_None);
if (EC)
fatal(EC, "failed to open " + ResFile.Path);
OS << MB.getBuffer();
OS.close();
E.add(ResFile.Path);
}
E.run();
return File.getMemoryBuffer();
}
// Run MSVC link.exe for given in-memory object files.
// Command line options are copied from those given to LLD.
// This is for the /msvclto option.
void runMSVCLinker(std::string Rsp, ArrayRef<StringRef> Objects) {
// Write the in-memory object files to disk.
std::vector<TemporaryFile> Temps;
for (StringRef S : Objects) {
Temps.emplace_back("lto", "obj", S);
Rsp += quote(Temps.back().Path) + " ";
}
log("link.exe " + Rsp);
// Run MSVC link.exe.
Temps.emplace_back("lto", "rsp", Rsp);
Executor E("link.exe");
E.add(Twine("@" + Temps.back().Path));
E.run();
}
// Create OptTable
// Create prefix string literals used in Options.td
#define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
#include "Options.inc"
#undef PREFIX
// Create table mapping all options defined in Options.td
static const llvm::opt::OptTable::Info infoTable[] = {
#define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X6, X7, X8, X9, X10) \
{ \
X1, X2, X9, X10, OPT_##ID, llvm::opt::Option::KIND##Class, X8, X7, \
OPT_##GROUP, OPT_##ALIAS, X6 \
},
#include "Options.inc"
#undef OPTION
};
class COFFOptTable : public llvm::opt::OptTable {
public:
COFFOptTable() : OptTable(infoTable, true) {}
};
// Parses a given list of options.
opt::InputArgList ArgParser::parse(ArrayRef<const char *> ArgsArr) {
// First, replace respnose files (@<file>-style options).
std::vector<const char *> Argv = replaceResponseFiles(ArgsArr);
// Make InputArgList from string vectors.
COFFOptTable Table;
unsigned MissingIndex;
unsigned MissingCount;
opt::InputArgList Args = Table.ParseArgs(Argv, MissingIndex, MissingCount);
// Print the real command line if response files are expanded.
if (Args.hasArg(OPT_verbose) && ArgsArr.size() != Argv.size()) {
std::string Msg = "Command line:";
for (const char *S : Argv)
Msg += " " + std::string(S);
message(Msg);
}
if (MissingCount)
fatal(Twine(Args.getArgString(MissingIndex)) + ": missing argument");
for (auto *Arg : Args.filtered(OPT_UNKNOWN))
warn("ignoring unknown argument: " + Arg->getSpelling());
return Args;
}
// link.exe has an interesting feature. If LINK environment exists,
// its contents are handled as a command line string. So you can pass
// extra arguments using the environment variable.
opt::InputArgList ArgParser::parseLINK(ArrayRef<const char *> Args) {
// Concatenate LINK env and command line arguments, and then parse them.
Optional<std::string> Env = Process::GetEnv("LINK");
if (!Env)
return parse(Args);
std::vector<const char *> V = tokenize(*Env);
V.insert(V.end(), Args.begin(), Args.end());
return parse(V);
}
std::vector<const char *> ArgParser::tokenize(StringRef S) {
SmallVector<const char *, 16> Tokens;
cl::TokenizeWindowsCommandLine(S, Saver, Tokens);
return std::vector<const char *>(Tokens.begin(), Tokens.end());
}
// Creates a new command line by replacing options starting with '@'
// character. '@<filename>' is replaced by the file's contents.
std::vector<const char *>
ArgParser::replaceResponseFiles(std::vector<const char *> Argv) {
SmallVector<const char *, 256> Tokens(Argv.data(), Argv.data() + Argv.size());
ExpandResponseFiles(Saver, TokenizeWindowsCommandLine, Tokens);
return std::vector<const char *>(Tokens.begin(), Tokens.end());
}
void printHelp(const char *Argv0) {
COFFOptTable Table;
Table.PrintHelp(outs(), Argv0, "LLVM Linker", false);
}
} // namespace coff
} // namespace lld
