llvm-project/lld/lib/Driver/Driver.cpp

143 lines
4.4 KiB
C++

//===- lib/Driver/Driver.cpp - Linker Driver Emulator ---------------------===//
//
// The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lld/Driver/Driver.h"
#include "lld/Core/LLVM.h"
#include "lld/Core/Instrumentation.h"
#include "lld/Core/PassManager.h"
#include "lld/Core/Parallel.h"
#include "lld/Core/Resolver.h"
#include "lld/ReaderWriter/Reader.h"
#include "lld/ReaderWriter/Writer.h"
#include "lld/Passes/RoundTripNativePass.h"
#include "lld/Passes/RoundTripYAMLPass.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/Option/Arg.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/Process.h"
#include "llvm/Support/raw_ostream.h"
#include <mutex>
namespace lld {
/// This is where the link is actually performed.
bool Driver::link(LinkingContext &context, raw_ostream &diagnostics) {
// Honor -mllvm
if (!context.llvmOptions().empty()) {
unsigned numArgs = context.llvmOptions().size();
const char **args = new const char *[numArgs + 2];
args[0] = "lld (LLVM option parsing)";
for (unsigned i = 0; i != numArgs; ++i)
args[i + 1] = context.llvmOptions()[i];
args[numArgs + 1] = 0;
llvm::cl::ParseCommandLineOptions(numArgs + 1, args);
}
InputGraph &inputGraph = context.getInputGraph();
if (!inputGraph.size())
return false;
inputGraph.normalize();
bool fail = false;
// Read inputs
ScopedTask readTask(getDefaultDomain(), "Read Args");
TaskGroup tg;
std::mutex diagnosticsMutex;
for (std::unique_ptr<InputElement> &ie : inputGraph.inputElements()) {
tg.spawn([&] {
// Writes to the same output stream is not guaranteed to be thread-safe.
// We buffer the diagnostics output to a separate string-backed output
// stream, acquire the lock, and then print it out.
std::string buf;
llvm::raw_string_ostream stream(buf);
if (std::error_code ec = ie->parse(context, stream)) {
if (FileNode *fileNode = dyn_cast<FileNode>(ie.get()))
stream << fileNode->errStr(ec) << "\n";
else if (dyn_cast<Group>(ie.get()))
// FIXME: We need a better diagnostics here
stream << "Cannot parse group input element\n";
else
llvm_unreachable("Unknown type of input element");
fail = true;
}
stream.flush();
if (!buf.empty()) {
std::lock_guard<std::mutex> lock(diagnosticsMutex);
diagnostics << buf;
}
});
}
tg.sync();
readTask.end();
if (fail)
return false;
std::unique_ptr<SimpleFileNode> fileNode(
new SimpleFileNode("Internal Files"));
InputGraph::FileVectorT internalFiles;
context.createInternalFiles(internalFiles);
if (internalFiles.size())
fileNode->addFiles(std::move(internalFiles));
// Give target a chance to add files.
InputGraph::FileVectorT implicitFiles;
context.createImplicitFiles(implicitFiles);
if (implicitFiles.size())
fileNode->addFiles(std::move(implicitFiles));
context.getInputGraph().insertElementAt(std::move(fileNode),
InputGraph::Position::BEGIN);
// Do core linking.
ScopedTask resolveTask(getDefaultDomain(), "Resolve");
Resolver resolver(context);
if (!resolver.resolve())
return false;
std::unique_ptr<MutableFile> merged = resolver.resultFile();
resolveTask.end();
// Run passes on linked atoms.
ScopedTask passTask(getDefaultDomain(), "Passes");
PassManager pm;
context.addPasses(pm);
#ifndef NDEBUG
llvm::Optional<std::string> env = llvm::sys::Process::GetEnv("LLD_RUN_ROUNDTRIP_TEST");
if (env.hasValue() && !env.getValue().empty()) {
pm.add(std::unique_ptr<Pass>(new RoundTripYAMLPass(context)));
pm.add(std::unique_ptr<Pass>(new RoundTripNativePass(context)));
}
#endif
pm.runOnFile(merged);
passTask.end();
// Give linked atoms to Writer to generate output file.
ScopedTask writeTask(getDefaultDomain(), "Write");
if (std::error_code ec = context.writeFile(*merged)) {
diagnostics << "Failed to write file '" << context.outputPath()
<< "': " << ec.message() << "\n";
return false;
}
return true;
}
} // namespace