[LLD] Fix Clang-tidy misc-unused-using-decls and Include What You Use warnings

[Eugene.Zelenko]

Summary

I checked this patch on my own build on RHEL 6. Regressions were OK.

[ruiu]

LGTM

lld/trunk/COFF/InputFiles.cpp

 //===- InputFiles.cpp -----------------------------------------------------===//
 //
 //                             The LLVM Linker
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "Chunks.h"
+#include "Config.h"
 #include "Error.h"
 #include "InputFiles.h"
 #include "Symbols.h"
-#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/ADT/Twine.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/LTO/LTOModule.h"
+#include "llvm/Object/Binary.h"
 #include "llvm/Object/COFF.h"
 #include "llvm/Support/COFF.h"
-#include "llvm/Support/Debug.h"
+#include "llvm/Support/Casting.h"
 #include "llvm/Support/Endian.h"
-#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/ErrorOr.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Target/TargetOptions.h"
+#include "llvm-c/lto.h"
+#include <cstring>
+#include <system_error>
+#include <utility>
 
 using namespace llvm::COFF;
 using namespace llvm::object;
 using namespace llvm::support::endian;
+
 using llvm::Triple;
 using llvm::support::ulittle32_t;
-using llvm::sys::fs::file_magic;
-using llvm::sys::fs::identify_magic;
 
 namespace lld {
 namespace coff {
 
 int InputFile::NextIndex = 0;
 llvm::LLVMContext BitcodeFile::Context;
 
 // Returns the last element of a path, which is supposed to be a filename.

lld/trunk/lib/ReaderWriter/FileArchive.cpp

 //===- lib/ReaderWriter/FileArchive.cpp -----------------------------------===//
 //
 //                             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/LLVM.h"
-#include "lld/Core/LinkingContext.h"
-#include "lld/Driver/Driver.h"
-#include "llvm/ADT/Hashing.h"
+#include "lld/Core/Reader.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Object/Archive.h"
-#include "llvm/Object/ObjectFile.h"
 #include "llvm/Support/Debug.h"
-#include "llvm/Support/Format.h"
 #include "llvm/Support/MemoryBuffer.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Object/Error.h"
+#include "llvm/Support/ErrorOr.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/raw_ostream.h"
 #include <memory>
 #include <set>
+#include <string>
+#include <system_error>
 #include <unordered_map>
+#include <utility>
+#include <vector>
 
 using llvm::object::Archive;
-using llvm::object::ObjectFile;
-using llvm::object::SymbolRef;
-using llvm::object::symbol_iterator;
-using llvm::object::object_error;
 
 namespace lld {
 
 namespace {
 
 /// \brief The FileArchive class represents an Archive Library file
 class FileArchive : public lld::ArchiveLibraryFile {
 public:

 };
 
 } // anonymous namespace
 
 void Registry::addSupportArchives(bool logLoading) {
   add(std::unique_ptr<Reader>(new ArchiveReader(logLoading)));
 }
 
-} // end namespace lld
+} // namespace lld

lld/trunk/unittests/MachOTests/MachONormalizedFileBinaryReaderTests.cpp

 //===- lld/unittest/MachOTests/MachONormalizedFileBinaryReaderTests.cpp ---===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "gtest/gtest.h"
 #include "../../lib/ReaderWriter/MachO/MachONormalizedFile.h"
+#include "lld/ReaderWriter/MachOLinkingContext.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Error.h"
 #include "llvm/Support/MachO.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/YAMLTraits.h"
+#include <cstdint>
+#include <memory>
 
 using llvm::StringRef;
 using llvm::MemoryBuffer;
-using llvm::ErrorOr;
 
 using namespace lld::mach_o::normalized;
 using namespace llvm::MachO;
 
 static std::unique_ptr<NormalizedFile>
 fromBinary(const uint8_t bytes[], unsigned length, StringRef archStr) {
   StringRef sr((const char*)bytes, length);
   std::unique_ptr<MemoryBuffer> mb(MemoryBuffer::getMemBuffer(sr, "", false));

lld/trunk/unittests/MachOTests/MachONormalizedFileToAtomsTests.cpp

 //===- lld/unittest/MachOTests/MachONormalizedFileToAtomsTests.cpp --------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "gtest/gtest.h"
 #include "../../lib/ReaderWriter/MachO/MachONormalizedFile.h"
+#include "lld/Core/Atom.h"
+#include "lld/Core/DefinedAtom.h"
+#include "lld/Core/File.h"
+#include "lld/Core/UndefinedAtom.h"
+#include "lld/ReaderWriter/MachOLinkingContext.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/Support/Error.h"
 #include "llvm/Support/MachO.h"
-
-using llvm::ErrorOr;
+#include "llvm/Support/YAMLTraits.h"
+#include <cstdint>
+#include <memory>
 
 using namespace lld::mach_o::normalized;
 using namespace llvm::MachO;
 
 TEST(ToAtomsTest, empty_obj_x86_64) {
   NormalizedFile f;
   f.arch = lld::MachOLinkingContext::arch_x86_64;
   llvm::Expected<std::unique_ptr<const lld::File>> atom_f =

lld/trunk/unittests/MachOTests/MachONormalizedFileYAMLTests.cpp

 //===- lld/unittest/MachOTests/MachONormalizedFileYAMLTests.cpp -----------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "gtest/gtest.h"
 #include "../../lib/ReaderWriter/MachO/MachONormalizedFile.h"
+#include "lld/ReaderWriter/MachOLinkingContext.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Error.h"
 #include "llvm/Support/MachO.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cstdint>
+#include <memory>
+#include <system_error>
+#include <string>
 
 using llvm::StringRef;
 using llvm::MemoryBuffer;
-using llvm::ErrorOr;
 using lld::mach_o::normalized::NormalizedFile;
 using lld::mach_o::normalized::Symbol;
 using lld::mach_o::normalized::Section;
 using lld::mach_o::normalized::Relocation;
 
 static std::unique_ptr<NormalizedFile> fromYAML(StringRef str) {
   std::unique_ptr<MemoryBuffer> mb(MemoryBuffer::getMemBuffer(str));
   llvm::Expected<std::unique_ptr<NormalizedFile>> r