llvm-project/lld/MachO/DriverUtils.cpp

353 lines
11 KiB
C++

//===- DriverUtils.cpp ----------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "Config.h"
#include "Driver.h"
#include "InputFiles.h"
#include "ObjC.h"
#include "Target.h"
#include "lld/Common/Args.h"
#include "lld/Common/CommonLinkerContext.h"
#include "lld/Common/Reproduce.h"
#include "llvm/ADT/CachedHashString.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/LTO/LTO.h"
#include "llvm/Option/Arg.h"
#include "llvm/Option/ArgList.h"
#include "llvm/Option/Option.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Path.h"
#include "llvm/TextAPI/InterfaceFile.h"
#include "llvm/TextAPI/TextAPIReader.h"
using namespace llvm;
using namespace llvm::MachO;
using namespace llvm::opt;
using namespace llvm::sys;
using namespace lld;
using namespace lld::macho;
// Create prefix string literals used in Options.td
#define PREFIX(NAME, VALUE) const char *NAME[] = VALUE;
#include "Options.inc"
#undef PREFIX
// Create table mapping all options defined in Options.td
static const OptTable::Info optInfo[] = {
#define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X7, X8, X9, X10, X11, X12) \
{X1, X2, X10, X11, OPT_##ID, Option::KIND##Class, \
X9, X8, OPT_##GROUP, OPT_##ALIAS, X7, X12},
#include "Options.inc"
#undef OPTION
};
MachOOptTable::MachOOptTable() : OptTable(optInfo) {}
// Set color diagnostics according to --color-diagnostics={auto,always,never}
// or --no-color-diagnostics flags.
static void handleColorDiagnostics(InputArgList &args) {
const Arg *arg =
args.getLastArg(OPT_color_diagnostics, OPT_color_diagnostics_eq,
OPT_no_color_diagnostics);
if (!arg)
return;
if (arg->getOption().getID() == OPT_color_diagnostics) {
lld::errs().enable_colors(true);
} else if (arg->getOption().getID() == OPT_no_color_diagnostics) {
lld::errs().enable_colors(false);
} else {
StringRef s = arg->getValue();
if (s == "always")
lld::errs().enable_colors(true);
else if (s == "never")
lld::errs().enable_colors(false);
else if (s != "auto")
error("unknown option: --color-diagnostics=" + s);
}
}
InputArgList MachOOptTable::parse(ArrayRef<const char *> argv) {
// Make InputArgList from string vectors.
unsigned missingIndex;
unsigned missingCount;
SmallVector<const char *, 256> vec(argv.data(), argv.data() + argv.size());
// Expand response files (arguments in the form of @<filename>)
// and then parse the argument again.
cl::ExpandResponseFiles(saver(), cl::TokenizeGNUCommandLine, vec);
InputArgList args = ParseArgs(vec, missingIndex, missingCount);
// Handle -fatal_warnings early since it converts missing argument warnings
// to errors.
errorHandler().fatalWarnings = args.hasArg(OPT_fatal_warnings);
if (missingCount)
error(Twine(args.getArgString(missingIndex)) + ": missing argument");
handleColorDiagnostics(args);
for (const Arg *arg : args.filtered(OPT_UNKNOWN)) {
std::string nearest;
if (findNearest(arg->getAsString(args), nearest) > 1)
error("unknown argument '" + arg->getAsString(args) + "'");
else
error("unknown argument '" + arg->getAsString(args) +
"', did you mean '" + nearest + "'");
}
return args;
}
void MachOOptTable::printHelp(const char *argv0, bool showHidden) const {
OptTable::printHelp(lld::outs(),
(std::string(argv0) + " [options] file...").c_str(),
"LLVM Linker", showHidden);
lld::outs() << "\n";
}
static std::string rewritePath(StringRef s) {
if (fs::exists(s))
return relativeToRoot(s);
return std::string(s);
}
static std::string rewriteInputPath(StringRef s) {
// Don't bother rewriting "absolute" paths that are actually under the
// syslibroot; simply rewriting the syslibroot is sufficient.
if (rerootPath(s) == s && fs::exists(s))
return relativeToRoot(s);
return std::string(s);
}
// Reconstructs command line arguments so that so that you can re-run
// the same command with the same inputs. This is for --reproduce.
std::string macho::createResponseFile(const InputArgList &args) {
SmallString<0> data;
raw_svector_ostream os(data);
// Copy the command line to the output while rewriting paths.
for (const Arg *arg : args) {
switch (arg->getOption().getID()) {
case OPT_reproduce:
break;
case OPT_INPUT:
os << quote(rewriteInputPath(arg->getValue())) << "\n";
break;
case OPT_o:
os << "-o " << quote(path::filename(arg->getValue())) << "\n";
break;
case OPT_filelist:
if (Optional<MemoryBufferRef> buffer = readFile(arg->getValue()))
for (StringRef path : args::getLines(*buffer))
os << quote(rewriteInputPath(path)) << "\n";
break;
case OPT_force_load:
case OPT_weak_library:
os << arg->getSpelling() << " "
<< quote(rewriteInputPath(arg->getValue())) << "\n";
break;
case OPT_F:
case OPT_L:
case OPT_bundle_loader:
case OPT_exported_symbols_list:
case OPT_order_file:
case OPT_rpath:
case OPT_syslibroot:
case OPT_unexported_symbols_list:
os << arg->getSpelling() << " " << quote(rewritePath(arg->getValue()))
<< "\n";
break;
case OPT_sectcreate:
os << arg->getSpelling() << " " << quote(arg->getValue(0)) << " "
<< quote(arg->getValue(1)) << " "
<< quote(rewritePath(arg->getValue(2))) << "\n";
break;
default:
os << toString(*arg) << "\n";
}
}
return std::string(data.str());
}
static void searchedDylib(const Twine &path, bool found) {
if (config->printDylibSearch)
message("searched " + path + (found ? ", found " : ", not found"));
if (!found)
depTracker->logFileNotFound(path);
}
Optional<StringRef> macho::resolveDylibPath(StringRef dylibPath) {
// TODO: if a tbd and dylib are both present, we should check to make sure
// they are consistent.
SmallString<261> tbdPath = dylibPath;
path::replace_extension(tbdPath, ".tbd");
bool tbdExists = fs::exists(tbdPath);
searchedDylib(tbdPath, tbdExists);
if (tbdExists)
return saver().save(tbdPath.str());
bool dylibExists = fs::exists(dylibPath);
searchedDylib(dylibPath, dylibExists);
if (dylibExists)
return saver().save(dylibPath);
return {};
}
// It's not uncommon to have multiple attempts to load a single dylib,
// especially if it's a commonly re-exported core library.
static DenseMap<CachedHashStringRef, DylibFile *> loadedDylibs;
DylibFile *macho::loadDylib(MemoryBufferRef mbref, DylibFile *umbrella,
bool isBundleLoader, bool explicitlyLinked) {
CachedHashStringRef path(mbref.getBufferIdentifier());
DylibFile *&file = loadedDylibs[path];
if (file) {
if (explicitlyLinked)
file->explicitlyLinked = explicitlyLinked;
return file;
}
DylibFile *newFile;
file_magic magic = identify_magic(mbref.getBuffer());
if (magic == file_magic::tapi_file) {
Expected<std::unique_ptr<InterfaceFile>> result = TextAPIReader::get(mbref);
if (!result) {
error("could not load TAPI file at " + mbref.getBufferIdentifier() +
": " + toString(result.takeError()));
return nullptr;
}
file =
make<DylibFile>(**result, umbrella, isBundleLoader, explicitlyLinked);
// parseReexports() can recursively call loadDylib(). That's fine since
// we wrote the DylibFile we just loaded to the loadDylib cache via the
// `file` reference. But the recursive load can grow loadDylibs, so the
// `file` reference might become invalid after parseReexports() -- so copy
// the pointer it refers to before continuing.
newFile = file;
if (newFile->exportingFile)
newFile->parseReexports(**result);
} else {
assert(magic == file_magic::macho_dynamically_linked_shared_lib ||
magic == file_magic::macho_dynamically_linked_shared_lib_stub ||
magic == file_magic::macho_executable ||
magic == file_magic::macho_bundle);
file = make<DylibFile>(mbref, umbrella, isBundleLoader, explicitlyLinked);
// parseLoadCommands() can also recursively call loadDylib(). See comment
// in previous block for why this means we must copy `file` here.
newFile = file;
if (newFile->exportingFile)
newFile->parseLoadCommands(mbref);
}
return newFile;
}
void macho::resetLoadedDylibs() { loadedDylibs.clear(); }
Optional<StringRef>
macho::findPathCombination(const Twine &name,
const std::vector<StringRef> &roots,
ArrayRef<StringRef> extensions) {
SmallString<261> base;
for (StringRef dir : roots) {
base = dir;
path::append(base, name);
for (StringRef ext : extensions) {
Twine location = base + ext;
bool exists = fs::exists(location);
searchedDylib(location, exists);
if (exists)
return saver().save(location.str());
}
}
return {};
}
StringRef macho::rerootPath(StringRef path) {
if (!path::is_absolute(path, path::Style::posix) || path.endswith(".o"))
return path;
if (Optional<StringRef> rerootedPath =
findPathCombination(path, config->systemLibraryRoots))
return *rerootedPath;
return path;
}
uint32_t macho::getModTime(StringRef path) {
if (config->zeroModTime)
return 0;
fs::file_status stat;
if (!fs::status(path, stat))
if (fs::exists(stat))
return toTimeT(stat.getLastModificationTime());
warn("failed to get modification time of " + path);
return 0;
}
void macho::printArchiveMemberLoad(StringRef reason, const InputFile *f) {
if (config->printEachFile)
message(toString(f));
if (config->printWhyLoad)
message(reason + " forced load of " + toString(f));
}
macho::DependencyTracker::DependencyTracker(StringRef path)
: path(path), active(!path.empty()) {
if (active && fs::exists(path) && !fs::can_write(path)) {
warn("Ignoring dependency_info option since specified path is not "
"writeable.");
active = false;
}
}
void macho::DependencyTracker::write(StringRef version,
const SetVector<InputFile *> &inputs,
StringRef output) {
if (!active)
return;
std::error_code ec;
raw_fd_ostream os(path, ec, fs::OF_None);
if (ec) {
warn("Error writing dependency info to file");
return;
}
auto addDep = [&os](DepOpCode opcode, const StringRef &path) {
// XXX: Even though DepOpCode's underlying type is uint8_t,
// this cast is still needed because Clang older than 10.x has a bug,
// where it doesn't know to cast the enum to its underlying type.
// Hence `<< DepOpCode` is ambiguous to it.
os << static_cast<uint8_t>(opcode);
os << path;
os << '\0';
};
addDep(DepOpCode::Version, version);
// Sort the input by its names.
std::vector<StringRef> inputNames;
inputNames.reserve(inputs.size());
for (InputFile *f : inputs)
inputNames.push_back(f->getName());
llvm::sort(inputNames);
for (const StringRef &in : inputNames)
addDep(DepOpCode::Input, in);
for (const std::string &f : notFounds)
addDep(DepOpCode::NotFound, f);
addDep(DepOpCode::Output, output);
}