Use more range-based for loops

[dougk]

Summary

And add Arg::getValues method with const 'this' and const result.

As requested by Sean Silva in http://reviews.llvm.org/D10689 but split out for separate review.

[dblaikie]

Looks good - feel free to commit this sort of cleanup in areas you're working directly/with post-commit review.

include/llvm/Option/Arg.h

public:
   /// \brief Set the Arg claimed bit.
   void claim() const { getBaseArg().Claimed = true; }
 
   unsigned getNumValues() const { return Values.size(); }
   const char *getValue(unsigned N = 0) const {
     return Values[N];
   }
 
-  SmallVectorImpl<const char*> &getValues() {
-    return Values;
-  }
+  SmallVectorImpl<const char *> &getValues() { return Values; }
+  const SmallVectorImpl<const char *> &getValues() const { return Values; }
 
   bool containsValue(StringRef Value) const {
     for (unsigned i = 0, e = getNumValues(); i != e; ++i)
       if (Values[i] == Value)
         return true;
     return false;
   }
 

lib/Driver/Driver.cpp

Driver::~Driver() {
 
   llvm::DeleteContainerSeconds(ToolChains);
 }
 
 void Driver::ParseDriverMode(ArrayRef<const char *> Args) {
   const std::string OptName =
     getOpts().getOption(options::OPT_driver_mode).getPrefixedName();
 
-  for (size_t I = 0, E = Args.size(); I != E; ++I) {
+  for (const char *ArgPtr : Args) {
     // Ingore nullptrs, they are response file's EOL markers
-    if (Args[I] == nullptr)
+    if (ArgPtr == nullptr)
       continue;
-    const StringRef Arg = Args[I];
+    const StringRef Arg = ArgPtr;
     if (!Arg.startswith(OptName))
       continue;
 
     const StringRef Value = Arg.drop_front(OptName.size());
     const unsigned M = llvm::StringSwitch<unsigned>(Value)
         .Case("gcc", GCCMode)
         .Case("g++", GXXMode)
         .Case("cpp", CPPMode)
int Driver::ExecuteCompilation(Compilation &C,
   C.CleanupFileList(C.getTempFiles());
 
   // If the command succeeded, we are done.
   if (FailingCommands.empty())
     return 0;
 
   // Otherwise, remove result files and print extra information about abnormal
   // failures.
-  for (SmallVectorImpl< std::pair<int, const Command *> >::iterator it =
-         FailingCommands.begin(), ie = FailingCommands.end(); it != ie; ++it) {
-    int Res = it->first;
-    const Command *FailingCommand = it->second;
+  for (const auto &CmdPair : FailingCommands) {
+    int Res = CmdPair.first;
+    const Command *FailingCommand = CmdPair.second;
 
     // Remove result files if we're not saving temps.
     if (!isSaveTempsEnabled()) {
       const JobAction *JA = cast<JobAction>(&FailingCommand->getSource());
       C.CleanupFileMap(C.getResultFiles(), JA, true);
 
       // Failure result files are valid unless we crashed.
       if (Res < 0)
if (C.getArgs().hasArg(options::OPT_print_multi_lib)) {
     for (MultilibSet::const_iterator I = Multilibs.begin(), E = Multilibs.end();
          I != E; ++I) {
       llvm::outs() << *I << "\n";
     }
     return false;
   }
 
   if (C.getArgs().hasArg(options::OPT_print_multi_directory)) {
-    const MultilibSet &Multilibs = TC.getMultilibs();
-    for (MultilibSet::const_iterator I = Multilibs.begin(), E = Multilibs.end();
-         I != E; ++I) {
-      if (I->gccSuffix().empty())
+    for (const auto &Multilib : TC.getMultilibs()) {
+      if (Multilib.gccSuffix().empty())
         llvm::outs() << ".\n";
       else {
-        StringRef Suffix(I->gccSuffix());
+        StringRef Suffix(Multilib.gccSuffix());
         assert(Suffix.front() == '/');
         llvm::outs() << Suffix.substr(1) << "\n";
       }
     }
     return false;
   }
 
   if (C.getArgs().hasArg(options::OPT_print_multi_os_directory)) {

lib/Driver/ToolChains.cpp

if (A->getOption().matches(options::OPT_Xarch__)) {
       A = XarchArg.release();
       DAL->AddSynthesizedArg(A);
 
       // Linker input arguments require custom handling. The problem is that we
       // have already constructed the phase actions, so we can not treat them as
       // "input arguments".
       if (A->getOption().hasFlag(options::LinkerInput)) {
         // Convert the argument into individual Zlinker_input_args.
-        for (unsigned i = 0, e = A->getNumValues(); i != e; ++i) {
-          DAL->AddSeparateArg(OriginalArg,
-                              Opts.getOption(options::OPT_Zlinker_input),
-                              A->getValue(i));
-
+        for (const char *Value : A->getValues()) {
+          DAL->AddSeparateArg(
+              OriginalArg, Opts.getOption(options::OPT_Zlinker_input), Value);
         }
         continue;
       }
     }
 
     // Sob. These is strictly gcc compatible for the time being. Apple
     // gcc translates options twice, which means that self-expanding
     // options add duplicates.
if (GCCToolchainDir != "") {
     // And finally in /usr.
     if (D.SysRoot.empty())
       Prefixes.push_back("/usr");
   }
 
   // Loop over the various components which exist and select the best GCC
   // installation available. GCC installs are ranked by version number.
   Version = GCCVersion::Parse("0.0.0");
-  for (unsigned i = 0, ie = Prefixes.size(); i < ie; ++i) {
-    if (!llvm::sys::fs::exists(Prefixes[i]))
+  for (const std::string &Prefix : Prefixes) {
+    if (!llvm::sys::fs::exists(Prefix))
       continue;
-    for (unsigned j = 0, je = CandidateLibDirs.size(); j < je; ++j) {
-      const std::string LibDir = Prefixes[i] + CandidateLibDirs[j].str();
+    for (const StringRef Suffix : CandidateLibDirs) {
+      const std::string LibDir = Prefix + Suffix.str();
       if (!llvm::sys::fs::exists(LibDir))
         continue;
-      for (unsigned k = 0, ke = CandidateTripleAliases.size(); k < ke; ++k)
-        ScanLibDirForGCCTriple(TargetTriple, Args, LibDir,
-                               CandidateTripleAliases[k]);
+      for (const StringRef Candidate : CandidateTripleAliases)
+        ScanLibDirForGCCTriple(TargetTriple, Args, LibDir, Candidate);
     }
-    for (unsigned j = 0, je = CandidateBiarchLibDirs.size(); j < je; ++j) {
-      const std::string LibDir = Prefixes[i] + CandidateBiarchLibDirs[j].str();
+    for (const StringRef Suffix : CandidateBiarchLibDirs) {
+      const std::string LibDir = Prefix + Suffix.str();
       if (!llvm::sys::fs::exists(LibDir))
         continue;
-      for (unsigned k = 0, ke = CandidateBiarchTripleAliases.size(); k < ke;
-           ++k)
-        ScanLibDirForGCCTriple(TargetTriple, Args, LibDir,
-                               CandidateBiarchTripleAliases[k],
+      for (const StringRef Candidate : CandidateBiarchTripleAliases)
+        ScanLibDirForGCCTriple(TargetTriple, Args, LibDir, Candidate,
                                /*NeedsBiarchSuffix=*/ true);
     }
   }
 }
 
 void Generic_GCC::GCCInstallationDetector::print(raw_ostream &OS) const {
   for (const auto &InstallPath : CandidateGCCInstallPaths)
     OS << "Found candidate GCC installation: " << InstallPath << "\n";
static void GetHexagonLibraryPaths(
   const std::string &InstalledDir,
   ToolChain::path_list *LibPaths)
 {
   bool buildingLib = Args.hasArg(options::OPT_shared);
 
   //----------------------------------------------------------------------------
   // -L Args
   //----------------------------------------------------------------------------
-  for (const Arg *A : Args.filtered(options::OPT_L))
-    for (unsigned i = 0, e = A->getNumValues(); i != e; ++i)
-      LibPaths->push_back(A->getValue(i));
+  for (Arg *A : Args.filtered(options::OPT_L))
+    for (const char *Value : A->getValues())
+      LibPaths->push_back(Value);
 
   //----------------------------------------------------------------------------
   // Other standard paths
   //----------------------------------------------------------------------------
   const std::string MarchSuffix = "/" + MarchString;
   const std::string G0Suffix = "/G0";
   const std::string MarchG0Suffix = MarchSuffix + G0Suffix;
   const std::string RootDir = Hexagon_TC::GetGnuDir(InstalledDir, Args) + "/";

 static Distro DetectDistro(llvm::Triple::ArchType Arch) {
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
       llvm::MemoryBuffer::getFile("/etc/lsb-release");
   if (File) {
     StringRef Data = File.get()->getBuffer();
     SmallVector<StringRef, 16> Lines;
     Data.split(Lines, "\n");
     Distro Version = UnknownDistro;
-    for (unsigned i = 0, s = Lines.size(); i != s; ++i)
-      if (Version == UnknownDistro && Lines[i].startswith("DISTRIB_CODENAME="))
-        Version = llvm::StringSwitch<Distro>(Lines[i].substr(17))
+    for (const StringRef Line : Lines)
+      if (Version == UnknownDistro && Line.startswith("DISTRIB_CODENAME="))
+        Version = llvm::StringSwitch<Distro>(Line.substr(17))
                       .Case("hardy", UbuntuHardy)
                       .Case("intrepid", UbuntuIntrepid)
                       .Case("jaunty", UbuntuJaunty)
                       .Case("karmic", UbuntuKarmic)
                       .Case("lucid", UbuntuLucid)
                       .Case("maverick", UbuntuMaverick)
                       .Case("natty", UbuntuNatty)
                       .Case("oneiric", UbuntuOneiric)
                       .Case("precise", UbuntuPrecise)
                       .Case("quantal", UbuntuQuantal)
                       .Case("raring", UbuntuRaring)
                       .Case("saucy", UbuntuSaucy)
                       .Case("trusty", UbuntuTrusty)
                       .Case("utopic", UbuntuUtopic)
                       .Case("vivid", UbuntuVivid)
                       .Default(UnknownDistro);
     return Version;
   }
 
   File = llvm::MemoryBuffer::getFile("/etc/redhat-release");
   if (File) {
     StringRef Data = File.get()->getBuffer();
     if (Data.startswith("Fedora release"))
       return Fedora;

lib/Driver/Tools.cpp

static void ParseMRecip(const Driver &D, const ArgList &Args,
   OptionStrings.insert(std::make_pair("divf",       false));
   OptionStrings.insert(std::make_pair("vec-divd",   false));
   OptionStrings.insert(std::make_pair("vec-divf",   false));
   OptionStrings.insert(std::make_pair("sqrtd",      false));
   OptionStrings.insert(std::make_pair("sqrtf",      false));
   OptionStrings.insert(std::make_pair("vec-sqrtd",  false));
   OptionStrings.insert(std::make_pair("vec-sqrtf",  false));
 
+  // If the test involving 'i' at the end of the loop is eliminated
+  // by prepending the comma on all except the first iteration instead of
+  // appending it on all except the ultimate, then this becomes
+  // "for (StringRef Val : A->getValues()) {" which seems a touch nicer.
   for (unsigned i = 0; i != NumOptions; ++i) {
     StringRef Val = A->getValue(i);
 
     bool IsDisabled = Val.startswith(DisabledPrefixIn);
     // Ignore the disablement token for string matching.
     if (IsDisabled)
       Val = Val.substr(1);
 
static void CollectArgsForIntegratedAssembler(Compilation &C,
 
     // When using an integrated assembler, translate -Wa, and -Xassembler
     // options.
     bool CompressDebugSections = false;
     for (const Arg *A :
          Args.filtered(options::OPT_Wa_COMMA, options::OPT_Xassembler)) {
       A->claim();
 
-      for (unsigned i = 0, e = A->getNumValues(); i != e; ++i) {
-        StringRef Value = A->getValue(i);
+      for (const StringRef Value : A->getValues()) {
         if (TakeNextArg) {
           CmdArgs.push_back(Value.data());
           TakeNextArg = false;
           continue;
         }
 
         if (Value == "-force_cpusubtype_ALL") {
           // Do nothing, this is the default and we don't support anything else.
#endif
   // analysis.
   if (getToolChain().UseDwarfDebugFlags()) {
     ArgStringList OriginalArgs;
     for (const auto &Arg : Args)
       Arg->render(Args, OriginalArgs);
 
     SmallString<256> Flags;
     Flags += Exec;
-    for (unsigned i = 0, e = OriginalArgs.size(); i != e; ++i) {
+    for (const char *OriginalArg : OriginalArgs) {
       SmallString<128> EscapedArg;
-      EscapeSpacesAndBackslashes(OriginalArgs[i], EscapedArg);
+      EscapeSpacesAndBackslashes(OriginalArg, EscapedArg);
       Flags += " ";
       Flags += EscapedArg;
     }
     CmdArgs.push_back("-dwarf-debug-flags");
     CmdArgs.push_back(Args.MakeArgString(Flags));
   }
 
   // Add the split debug info name to the command lines here so we
void ClangAs::ConstructJob(Compilation &C, const JobAction &JA,
   if (getToolChain().UseDwarfDebugFlags()) {
     ArgStringList OriginalArgs;
     for (const auto &Arg : Args)
       Arg->render(Args, OriginalArgs);
 
     SmallString<256> Flags;
     const char *Exec = getToolChain().getDriver().getClangProgramPath();
     Flags += Exec;
-    for (unsigned i = 0, e = OriginalArgs.size(); i != e; ++i) {
+    for (const char *OriginalArg : OriginalArgs) {
       SmallString<128> EscapedArg;
-      EscapeSpacesAndBackslashes(OriginalArgs[i], EscapedArg);
+      EscapeSpacesAndBackslashes(OriginalArg, EscapedArg);
       Flags += " ";
       Flags += EscapedArg;
     }
     CmdArgs.push_back("-dwarf-debug-flags");
     CmdArgs.push_back(Args.MakeArgString(Flags));
   }
 
   // FIXME: Add -static support, once we have it.