1 files changed, 130 insertions, 0 deletions
diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
new file mode 100644
index 000000000000..d32bfa6e47be
--- /dev/null
+++ b/lib/Driver/Driver.cpp
@@ -0,0 +1,130 @@
+//===- 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/Core/ArchiveLibraryFile.h"
+#include "lld/Core/File.h"
+#include "lld/Core/Instrumentation.h"
+#include "lld/Core/LLVM.h"
+#include "lld/Core/Parallel.h"
+#include "lld/Core/PassManager.h"
+#include "lld/Core/Reader.h"
+#include "lld/Core/Resolver.h"
+#include "lld/Core/Writer.h"
+#include "lld/Driver/Driver.h"
+#include "llvm/ADT/STLExtras.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 {
+
+FileVector makeErrorFile(StringRef path, std::error_code ec) {
+  std::vector<std::unique_ptr<File>> result;
+  result.push_back(llvm::make_unique<ErrorFile>(path, ec));
+  return result;
+}
+
+FileVector parseMemberFiles(FileVector &files) {
+  std::vector<std::unique_ptr<File>> members;
+  for (std::unique_ptr<File> &file : files) {
+    if (auto *archive = dyn_cast<ArchiveLibraryFile>(file.get())) {
+      if (std::error_code ec = archive->parseAllMembers(members))
+        return makeErrorFile(file->path(), ec);
+    } else {
+      members.push_back(std::move(file));
+    }
+  }
+  return members;
+}
+
+FileVector loadFile(LinkingContext &ctx, StringRef path, bool wholeArchive) {
+  ErrorOr<std::unique_ptr<MemoryBuffer>> mb
+      = MemoryBuffer::getFileOrSTDIN(path);
+  if (std::error_code ec = mb.getError())
+    return makeErrorFile(path, ec);
+  std::vector<std::unique_ptr<File>> files;
+  if (std::error_code ec = ctx.registry().loadFile(std::move(mb.get()), files))
+    return makeErrorFile(path, ec);
+  if (wholeArchive)
+    return parseMemberFiles(files);
+  return files;
+}
+
+/// 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);
+  }
+  if (context.getNodes().empty())
+    return false;
+
+  for (std::unique_ptr<Node> &ie : context.getNodes())
+    if (FileNode *node = dyn_cast<FileNode>(ie.get()))
+      context.getTaskGroup().spawn([node] { node->getFile()->parse(); });
+
+  std::vector<std::unique_ptr<File>> internalFiles;
+  context.createInternalFiles(internalFiles);
+  for (auto i = internalFiles.rbegin(), e = internalFiles.rend(); i != e; ++i) {
+    auto &members = context.getNodes();
+    members.insert(members.begin(), llvm::make_unique<FileNode>(std::move(*i)));
+  }
+
+  // Give target a chance to add files.
+  std::vector<std::unique_ptr<File>> implicitFiles;
+  context.createImplicitFiles(implicitFiles);
+  for (auto i = implicitFiles.rbegin(), e = implicitFiles.rend(); i != e; ++i) {
+    auto &members = context.getNodes();
+    members.insert(members.begin(), llvm::make_unique<FileNode>(std::move(*i)));
+  }
+
+  // Give target a chance to postprocess input files.
+  // Mach-O uses this chance to move all object files before library files.
+  // ELF adds specific undefined symbols resolver.
+  context.finalizeInputFiles();
+
+  // 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);
+  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