[LLD] Fix Clang-tidy modernize-use-nullptr warnings; other minor cleanups.

[Eugene.Zelenko]

Summary

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

Please check it in if it's OK, because I don't have SVN write access.

[ruiu]

LGTM

[Eugene.Zelenko]

Hi, Rui!

Could you please check in code since I don't have SVN write access?

[Eugene.Zelenko]

Closed by commit r249111: Fix Clang-tidy modernize-use-nullptr warnings; other minor cleanups. by ruiu.

tools/lld/COFF/ModuleDef.cpp

     read();
     if (Tok.K != Comma) {
       unget();
-      Commit = 0;
+      Commit = nullptr;
       return;
     }
     readAsInt(Commit);

tools/lld/lib/Driver/Driver.cpp

     args[0] = "lld (LLVM option parsing)";
     for (unsigned i = 0; i != numArgs; ++i)
       args[i + 1] = ctx.llvmOptions()[i];
-    args[numArgs + 1] = 0;
+    args[numArgs + 1] = nullptr;
     llvm::cl::ParseCommandLineOptions(numArgs + 1, args);
   }
   if (ctx.getNodes().empty())

   return true;
 }
 
-} // namespace
+} // anonymous namespace

tools/lld/lib/ReaderWriter/ELF/ELFLinkingContext.cpp

   const char *cstr = nullTermSym.data();
   int status;
   char *demangled = abi::__cxa_demangle(cstr, nullptr, nullptr, &status);
-  if (demangled == NULL)
+  if (!demangled)
     return symbolName;
   std::string result(demangled);
   // __cxa_demangle() always uses a malloc'ed buffer to return the result.

tools/lld/lib/ReaderWriter/MachO/LayoutPass.cpp

     AtomToAtomT::iterator start = _followOnRoots.find(atom);
     if (start == _followOnRoots.end())
       continue;
-    for (const DefinedAtom *nextAtom = start->second; nextAtom != NULL;
+    for (const DefinedAtom *nextAtom = start->second; nextAtom;
          nextAtom = _followOnNexts[nextAtom]) {
       AtomToOrdinalT::iterator pos = _ordinalOverrideMap.find(nextAtom);
       if (pos == _ordinalOverrideMap.end())

tools/lld/lib/ReaderWriter/MachO/MachOLinkingContext.cpp

   return false;
 }
 
-
 MachOLinkingContext::ArchInfo MachOLinkingContext::_s_archInfos[] = {
   { "x86_64", arch_x86_64, true,  CPU_TYPE_X86_64,  CPU_SUBTYPE_X86_64_ALL },
   { "i386",   arch_x86,    true,  CPU_TYPE_I386,    CPU_SUBTYPE_X86_ALL },

   llvm_unreachable("Unknown arch type");
 }
 
-
-
 bool MachOLinkingContext::is64Bit() const {
   return is64Bit(_arch);
 }

   return archHandler().stubInfo().binderSymbolName;
 }
 
-
-
-
 bool MachOLinkingContext::minOS(StringRef mac, StringRef iOS) const {
   uint32_t parsedVersion;
   switch (_os) {

     _frameworkDirs.push_back(fwPath);
 }
 
-
 ErrorOr<StringRef>
 MachOLinkingContext::searchDirForLibrary(StringRef path,
                                          StringRef libName) const {

   return make_error_code(llvm::errc::no_such_file_or_directory);
 }
 
-
-
 ErrorOr<StringRef> MachOLinkingContext::searchLibrary(StringRef libName) const {
   SmallString<256> path;
   for (StringRef dir : searchDirs()) {

   return make_error_code(llvm::errc::no_such_file_or_directory);
 }
 
-
 ErrorOr<StringRef> MachOLinkingContext::findPathForFramework(StringRef fwName) const{
   SmallString<256> fullPath;
   for (StringRef dir : frameworkDirs()) {

   return result;
 }
 
-
 MachODylibFile* MachOLinkingContext::findIndirectDylib(StringRef path) {
   // See if already loaded.
   auto pos = _pathToDylibMap.find(path);

   }
 }
 
-
 void MachOLinkingContext::registerDylib(MachODylibFile *dylib,
                                         bool upward) const {
   std::lock_guard<std::mutex> lock(_dylibsMutex);

     _upwardDylibs.insert(dylib);
 }
 
-
 bool MachOLinkingContext::isUpwardDylib(StringRef installName) const {
   for (MachODylibFile *dylib : _upwardDylibs) {
     if (dylib->installName().equals(installName))

   return *_archHandler;
 }
 
-
 void MachOLinkingContext::addSectionAlignment(StringRef seg, StringRef sect,
                                               uint16_t align) {
   SectionAlign entry = { seg, sect, align };

   return false;
 }
 
-
 void MachOLinkingContext::addExportSymbol(StringRef sym) {
   // Support old crufty export lists with bogus entries.
   if (sym.endswith(".eh") || sym.startswith(".objc_category_name_")) {

   const char *cstr = nullTermSym.data() + 1;
   int status;
   char *demangled = abi::__cxa_demangle(cstr, nullptr, nullptr, &status);
-  if (demangled != NULL) {
+  if (demangled) {
     std::string result(demangled);
     // __cxa_demangle() always uses a malloc'ed buffer to return the result.
     free(demangled);