Add support for the new mips-mti-linux toolchain.

[vkalintiris]

Summary

This new toolchain uses primarily LLVM-based tools, eg. compiler-rt, lld,
libcxx, etc. Because of this, it doesn't require neither an existing GCC
installation nor a GNU environment. Ideally, in a follow-up patch we
would like to add a new --{llvm|clang}-toolchain option (similar to
--gcc-toolchain) in order to allow the use of this toolchain with
independent Clang builds. For the time being, we use the --sysroot
option just to test the correctness of the paths generated by the
driver.

[atanasyan]

include/clang/Driver/ToolChain.h

92 ↗

(On Diff #36227)

This field is used by the MipsToolChain class only. If so, move it to that class.

147 ↗

(On Diff #36227)

Do you need public access to this member function?

lib/Driver/Driver.cpp

2127 ↗

(On Diff #36227)

Just curious when is DefaultTargetTriple not equal to LLVMDefaultTargetTriple?

2225 ↗

(On Diff #36227)

The mips-mti-linux-gnu triple is used by Codescape toolchain too. After this change if user provides -target mips-mti-linux-gnu command line option, the MipsToolChain will be used. As far as I understand you have to put GCCInstallation.isValid() checking to the MipsToolChain class methods to allow working with both GNU and non-GNU toolchains. IMHO it does not make the code clear. Maybe use the MipsToolChain class for the non-GNU toolchain only.

lib/Driver/ToolChains.cpp

2210 ↗

(On Diff #36227)

Let's make this change by a separate commit to reduce number of unrelated changes.

2231 ↗

(On Diff #36227)

When is GCCInstallation invalid in case of using this toolchain?

2243 ↗

(On Diff #36227)

Similar code exists in the getLinuxDynamicLinker routine. Let's factor out it into the separate function say tools::mips::getMipsABILibSuffix.

lib/Driver/Tools.cpp

8115 ↗

(On Diff #36227)

Let's make this change by a separate commit to reduce number of unrelated changes.

[vkalintiris]

Thanks. The review comments are addressed in this update.

include/clang/Driver/ToolChain.h

147 ↗

(On Diff #36227)

I discarded this member function after the move of SelectedMultilib to the MipsToolChain class.

lib/Driver/Driver.cpp

2127 ↗

(On Diff #36227)

In this case, DefaultTargetTriple is the triple specified with --target=. LLVMDefaultTargetTriple is the value specified with the CMake variable -DLLVM_DEFAULT_TARGET_TRIPLE= during configuration time. For example, using --target=mips64el-mti-linux will search for files prefixed with either mips64el-mti-linux-{as,ld} and mips-mti-linux-{as,ld} in our toolchain where we specify -DLLVM_DEFAULT_TARGET_TRIPLE=mips-mti-linux.

2225 ↗

(On Diff #36227)

Shall we change the MipsToolChain class name to reflect these changes? Maybe MipsNonGNUToolChain? It would be strange to keep the same name, because most of the MIPS toolchains wouldn't be instantiated by MipsToolChain.

lib/Driver/ToolChains.cpp

2231 ↗

(On Diff #36227)

I changed that, according to your comments earlier. Now we instantiate this class only for triples that don't have an environment.

[atanasyan]

lib/Driver/Driver.cpp

2225 ↗

(On Diff #36257)

Now I try to redesign Codescape toolchain support in the Clang driver. I consider to use a separate toolchain class like your MipsToolChain and I name it CodeScapeMtiToolChain. If I be able to join support for both MIT and IMG toolchains in the single class, I will rename it to CodeScapeToolChain.

Will this non-GNU toolchain have a personal name like CodeScape? If not I am okay with MipsNonGNUToolChain.

[vkalintiris]

lib/Driver/Driver.cpp

2225 ↗

(On Diff #36257)

I thought about this and I don't believe that MipsNonGNUToolChain is a very good name. The main reason is that the last component of the entries under the sysroot, contain the name of the C library (or empty for GLIBC). We could easily have a toolchain with mips-r2-hard{,-uClibc} installed for mips-mti-linux.

What are your thoughts about the names: MipsGCCToolChain, Mips{Clang,LLVM}ToolChain, or CodescapeGCCToolChain and CodescapeLLVMToolChain?

Personally, I'd prefer the first pair of names. The reason is that with this choice we will be consistent in the naming of our classes. Also, it's clear that these are MIPS TCs and we have to consider that the Codescape name could change in the future (improbable but not impossible).

The Mips{GCC,Clang/LLVM}Toolchain name would specify whether we are going to use the files generated from a GCC or Clang installation. This way we could keep the existing functionality of the Linux class for older toolchains that will be deprecated/unused over time.

[atanasyan]

lib/Driver/Driver.cpp

2225 ↗

(On Diff #36257)

It sounds reasonable. Let's use MipsGCCToolChain and MipsLLVMToolChain.

[vkalintiris]

1. s/MipsToolChain/MipsLLVMToolChain/
2. Change to the new getCompilerRT() return type
3. clang-format

[atanasyan]

LGTM

cfe/trunk/lib/Driver/Driver.cpp

 }
 
 void Driver::generatePrefixedToolNames(
     const char *Tool, const ToolChain &TC,
     SmallVectorImpl<std::string> &Names) const {
   // FIXME: Needs a better variable than DefaultTargetTriple
   Names.emplace_back(DefaultTargetTriple + "-" + Tool);
   Names.emplace_back(Tool);
+
+  // Allow the discovery of tools prefixed with LLVM's default target triple.
+  std::string LLVMDefaultTargetTriple = llvm::sys::getDefaultTargetTriple();
+  if (LLVMDefaultTargetTriple != DefaultTargetTriple)
+    Names.emplace_back(LLVMDefaultTargetTriple + "-" + Tool);
 }
 
 static bool ScanDirForExecutable(SmallString<128> &Dir,
                                  ArrayRef<std::string> Names) {
   for (const auto &Name : Names) {
     llvm::sys::path::append(Dir, Name);
     if (llvm::sys::fs::can_execute(Twine(Dir)))
       return true;
case llvm::Triple::FreeBSD:
       TC = new toolchains::FreeBSD(*this, Target, Args);
       break;
     case llvm::Triple::Minix:
       TC = new toolchains::Minix(*this, Target, Args);
       break;
     case llvm::Triple::Linux:
       if (Target.getArch() == llvm::Triple::hexagon)
         TC = new toolchains::HexagonToolChain(*this, Target, Args);
+      else if ((Target.getVendor() == llvm::Triple::MipsTechnologies) &&
+               !Target.hasEnvironment())
+        TC = new toolchains::MipsLLVMToolChain(*this, Target, Args);
       else
         TC = new toolchains::Linux(*this, Target, Args);
       break;
     case llvm::Triple::NaCl:
       TC = new toolchains::NaClToolChain(*this, Target, Args);
       break;
     case llvm::Triple::Solaris:
       TC = new toolchains::Solaris(*this, Target, Args);

cfe/trunk/lib/Driver/ToolChain.cpp

Tool *ToolChain::SelectTool(const JobAction &JA) const {
   Action::ActionClass AC = JA.getKind();
   if (AC == Action::AssembleJobClass && useIntegratedAs())
     return getClangAs();
   return getTool(AC);
 }
 
 std::string ToolChain::GetFilePath(const char *Name) const {
   return D.GetFilePath(Name, *this);
-
 }
 
 std::string ToolChain::GetProgramPath(const char *Name) const {
   return D.GetProgramPath(Name, *this);
 }
 
 std::string ToolChain::GetLinkerPath() const {
   if (Arg *A = Args.getLastArg(options::OPT_fuse_ld_EQ)) {

cfe/trunk/lib/Driver/ToolChains.h

public:
   void
   AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
                             llvm::opt::ArgStringList &CC1Args) const override;
   void AddClangCXXStdlibIncludeArgs(
       const llvm::opt::ArgList &DriverArgs,
       llvm::opt::ArgStringList &CC1Args) const override;
   bool isPIEDefault() const override;
   SanitizerMask getSupportedSanitizers() const override;
+  virtual std::string computeSysRoot() const;
 
   std::string Linker;
   std::vector<std::string> ExtraOpts;
 
 protected:
   Tool *buildAssembler() const override;
   Tool *buildLinker() const override;
 
 private:
   static bool addLibStdCXXIncludePaths(Twine Base, Twine Suffix,
                                        StringRef GCCTriple,
                                        StringRef GCCMultiarchTriple,
                                        StringRef TargetMultiarchTriple,
                                        Twine IncludeSuffix,
                                        const llvm::opt::ArgList &DriverArgs,
                                        llvm::opt::ArgStringList &CC1Args);
 
-  std::string computeSysRoot() const;
 };
 
 class LLVM_LIBRARY_VISIBILITY CudaToolChain : public Linux {
 public:
   CudaToolChain(const Driver &D, const llvm::Triple &Triple,
                 const llvm::opt::ArgList &Args);
 
   llvm::opt::DerivedArgList *
   TranslateArgs(const llvm::opt::DerivedArgList &Args,
                 const char *BoundArch) const override;
   void addClangTargetOptions(const llvm::opt::ArgList &DriverArgs,
                              llvm::opt::ArgStringList &CC1Args) const override;
 };
 
+class LLVM_LIBRARY_VISIBILITY MipsLLVMToolChain : public Linux {
+protected:
+  Tool *buildLinker() const override;
+
+public:
+  MipsLLVMToolChain(const Driver &D, const llvm::Triple &Triple,
+                    const llvm::opt::ArgList &Args);
+
+  void
+  AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
+                            llvm::opt::ArgStringList &CC1Args) const override;
+
+  CXXStdlibType GetCXXStdlibType(const llvm::opt::ArgList &Args) const override;
+
+  void AddClangCXXStdlibIncludeArgs(
+      const llvm::opt::ArgList &DriverArgs,
+      llvm::opt::ArgStringList &CC1Args) const override;
+
+  void AddCXXStdlibLibArgs(const llvm::opt::ArgList &Args,
+                           llvm::opt::ArgStringList &CmdArgs) const override;
+
+  std::string getCompilerRT(const llvm::opt::ArgList &Args, StringRef Component,
+                            bool Shared = false) const override;
+
+  std::string computeSysRoot() const override;
+
+  RuntimeLibType GetDefaultRuntimeLibType() const override {
+    return GCCInstallation.isValid() ? RuntimeLibType::RLT_Libgcc
+                                     : RuntimeLibType::RLT_CompilerRT;
+  }
+
+private:
+  Multilib SelectedMultilib;
+  std::string LibSuffix;
+};
+
 class LLVM_LIBRARY_VISIBILITY HexagonToolChain : public Linux {
 protected:
   GCCVersion GCCLibAndIncVersion;
   Tool *buildAssembler() const override;
   Tool *buildLinker() const override;
 
 public:
   HexagonToolChain(const Driver &D, const llvm::Triple &Triple,

cfe/trunk/lib/Driver/ToolChains.cpp

/*static*/ void Generic_GCC::GCCInstallationDetector::CollectLibDirsAndTriples(
   static const char *const X86Triples[] = {
       "i686-linux-gnu",       "i686-pc-linux-gnu",     "i486-linux-gnu",
       "i386-linux-gnu",       "i386-redhat-linux6E",   "i686-redhat-linux",
       "i586-redhat-linux",    "i386-redhat-linux",     "i586-suse-linux",
       "i486-slackware-linux", "i686-montavista-linux", "i686-linux-android",
       "i586-linux-gnu"};
 
   static const char *const MIPSLibDirs[] = {"/lib"};
-  static const char *const MIPSTriples[] = {
-      "mips-linux-gnu", "mips-mti-linux-gnu", "mips-img-linux-gnu"};
+  static const char *const MIPSTriples[] = {"mips-linux-gnu", "mips-mti-linux",
+                                            "mips-mti-linux-gnu",
+                                            "mips-img-linux-gnu"};
   static const char *const MIPSELLibDirs[] = {"/lib"};
   static const char *const MIPSELTriples[] = {
       "mipsel-linux-gnu", "mipsel-linux-android", "mips-img-linux-gnu"};
 
   static const char *const MIPS64LibDirs[] = {"/lib64", "/lib"};
   static const char *const MIPS64Triples[] = {
       "mips64-linux-gnu", "mips-mti-linux-gnu", "mips-img-linux-gnu",
       "mips64-linux-gnuabi64"};
FSFMipsMultilibs =
               if (StringRef(M.includeSuffix()).startswith("/uclibc"))
                 Dirs.push_back(SysRootInc + "/uclibc/usr/include");
               else
                 Dirs.push_back(SysRootInc + "/usr/include");
               return Dirs;
             });
   }
 
+  // Check for Musl toolchain multilibs
+  MultilibSet MuslMipsMultilibs;
+  {
+    auto MArchMipsR2 = makeMultilib("")
+                           .osSuffix("/mips-r2-hard-musl")
+                           .flag("+EB")
+                           .flag("-EL")
+                           .flag("+march=mips32r2");
+
+    auto MArchMipselR2 = makeMultilib("/mipsel-r2-hard-musl")
+                             .flag("-EB")
+                             .flag("+EL")
+                             .flag("+march=mips32r2");
+
+    MuslMipsMultilibs = MultilibSet().Either(MArchMipsR2, MArchMipselR2);
+
+    // Specify the callback that computes the include directories.
+    MuslMipsMultilibs.setIncludeDirsCallback([](
+        StringRef InstallDir, StringRef TripleStr, const Multilib &M) {
+      std::vector<std::string> Dirs;
+      Dirs.push_back(
+          (InstallDir + "/../sysroot" + M.osSuffix() + "/usr/include").str());
+      return Dirs;
+    });
+  }
+
   // Check for Code Sourcery toolchain multilibs
   MultilibSet CSMipsMultilibs;
   {
     auto MArchMips16 = makeMultilib("/mips16").flag("+m32").flag("+mips16");
 
     auto MArchMicroMips =
         makeMultilib("/micromips").flag("+m32").flag("+mmicromips");
 
if (TargetTriple.getEnvironment() == llvm::Triple::Android) {
     // Select Android toolchain. It's the only choice in that case.
     if (AndroidMipsMultilibs.select(Flags, Result.SelectedMultilib)) {
       Result.Multilibs = AndroidMipsMultilibs;
       return true;
     }
     return false;
   }
 
+  if (TargetTriple.getVendor() == llvm::Triple::MipsTechnologies &&
+      TargetTriple.getOS() == llvm::Triple::Linux &&
+      TargetTriple.getEnvironment() == llvm::Triple::UnknownEnvironment) {
+    if (MuslMipsMultilibs.select(Flags, Result.SelectedMultilib)) {
+      Result.Multilibs = MuslMipsMultilibs;
+      return true;
+    }
+    return false;
+  }
+
   if (TargetTriple.getVendor() == llvm::Triple::ImaginationTechnologies &&
       TargetTriple.getOS() == llvm::Triple::Linux &&
       TargetTriple.getEnvironment() == llvm::Triple::GNU) {
     // Select mips-img-linux-gnu toolchain.
     if (ImgMultilibs.select(Flags, Result.SelectedMultilib)) {
       Result.Multilibs = ImgMultilibs;
       return true;
     }
void Generic_ELF::addClangTargetOptions(const ArgList &DriverArgs,
                                         ArgStringList &CC1Args) const {
   const Generic_GCC::GCCVersion &V = GCCInstallation.getVersion();
   bool UseInitArrayDefault =
       getTriple().getArch() == llvm::Triple::aarch64 ||
       getTriple().getArch() == llvm::Triple::aarch64_be ||
       (getTriple().getOS() == llvm::Triple::Linux &&
        (!V.isOlderThan(4, 7, 0) ||
         getTriple().getEnvironment() == llvm::Triple::Android)) ||
-      getTriple().getOS() == llvm::Triple::NaCl;
+      getTriple().getOS() == llvm::Triple::NaCl ||
+      (getTriple().getVendor() == llvm::Triple::MipsTechnologies &&
+       !getTriple().hasEnvironment());
 
   if (DriverArgs.hasFlag(options::OPT_fuse_init_array,
                          options::OPT_fno_use_init_array, UseInitArrayDefault))
     CC1Args.push_back("-fuse-init-array");
 }
 
+/// Mips Toolchain
+MipsLLVMToolChain::MipsLLVMToolChain(const Driver &D,
+                                     const llvm::Triple &Triple,
+                                     const ArgList &Args)
+    : Linux(D, Triple, Args) {
+  // Select the correct multilib according to the given arguments.
+  DetectedMultilibs Result;
+  findMIPSMultilibs(Triple, "", Args, Result);
+  Multilibs = Result.Multilibs;
+  SelectedMultilib = Result.SelectedMultilib;
+
+  // Find out the library suffix based on the ABI.
+  LibSuffix = tools::mips::getMipsABILibSuffix(Args, Triple);
+  getFilePaths().clear();
+  getFilePaths().push_back(computeSysRoot() + "/usr/lib" + LibSuffix);
+
+  // Use LLD by default.
+  if (!Args.getLastArg(options::OPT_fuse_ld_EQ))
+    Linker = GetProgramPath("lld");
+}
+
+void MipsLLVMToolChain::AddClangSystemIncludeArgs(
+    const ArgList &DriverArgs, ArgStringList &CC1Args) const {
+  if (DriverArgs.hasArg(options::OPT_nostdinc))
+    return;
+
+  const Driver &D = getDriver();
+
+  if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
+    SmallString<128> P(D.ResourceDir);
+    llvm::sys::path::append(P, "include");
+    addSystemInclude(DriverArgs, CC1Args, P);
+  }
+
+  if (DriverArgs.hasArg(options::OPT_nostdlibinc))
+    return;
+
+  const auto &Callback = Multilibs.includeDirsCallback();
+  if (Callback) {
+    const auto IncludePaths =
+        Callback(D.getInstalledDir(), getTripleString(), SelectedMultilib);
+    for (const auto &Path : IncludePaths)
+      addExternCSystemIncludeIfExists(DriverArgs, CC1Args, Path);
+  }
+}
+
+Tool *MipsLLVMToolChain::buildLinker() const {
+  return new tools::gnutools::Linker(*this);
+}
+
+std::string MipsLLVMToolChain::computeSysRoot() const {
+  if (!getDriver().SysRoot.empty())
+    return getDriver().SysRoot + SelectedMultilib.osSuffix();
+
+  const std::string InstalledDir(getDriver().getInstalledDir());
+  std::string SysRootPath =
+      InstalledDir + "/../sysroot" + SelectedMultilib.osSuffix();
+  if (llvm::sys::fs::exists(SysRootPath))
+    return SysRootPath;
+
+  return std::string();
+}
+
+ToolChain::CXXStdlibType
+MipsLLVMToolChain::GetCXXStdlibType(const ArgList &Args) const {
+  Arg *A = Args.getLastArg(options::OPT_stdlib_EQ);
+  if (A) {
+    StringRef Value = A->getValue();
+    if (Value != "libc++")
+      getDriver().Diag(diag::err_drv_invalid_stdlib_name)
+          << A->getAsString(Args);
+  }
+
+  return ToolChain::CST_Libcxx;
+}
+
+void MipsLLVMToolChain::AddClangCXXStdlibIncludeArgs(
+    const ArgList &DriverArgs, ArgStringList &CC1Args) const {
+  if (DriverArgs.hasArg(options::OPT_nostdlibinc) ||
+      DriverArgs.hasArg(options::OPT_nostdincxx))
+    return;
+
+  assert((GetCXXStdlibType(DriverArgs) == ToolChain::CST_Libcxx) &&
+         "Only -lc++ (aka libcxx) is suported in this toolchain.");
+
+  const auto &Callback = Multilibs.includeDirsCallback();
+  if (Callback) {
+    const auto IncludePaths = Callback(getDriver().getInstalledDir(),
+                                       getTripleString(), SelectedMultilib);
+    for (const auto &Path : IncludePaths) {
+      if (llvm::sys::fs::exists(Path + "/c++/v1")) {
+        addSystemInclude(DriverArgs, CC1Args, Path + "/c++/v1");
+        break;
+      }
+    }
+  }
+}
+
+void MipsLLVMToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
+                                            ArgStringList &CmdArgs) const {
+  assert((GetCXXStdlibType(Args) == ToolChain::CST_Libcxx) &&
+         "Only -lc++ (aka libxx) is suported in this toolchain.");
+
+  CmdArgs.push_back("-lc++");
+  CmdArgs.push_back("-lc++abi");
+  CmdArgs.push_back("-lunwind");
+}
+
+std::string MipsLLVMToolChain::getCompilerRT(const ArgList &Args,
+                                             StringRef Component,
+                                             bool Shared) const {
+  SmallString<128> Path(getDriver().ResourceDir);
+  llvm::sys::path::append(Path, SelectedMultilib.osSuffix(), "lib" + LibSuffix,
+                          getOS());
+  llvm::sys::path::append(Path, Twine("libclang_rt." + Component + "-" +
+                                      getTriple().getArchName() +
+                                      (Shared ? ".so" : ".a")));
+  return Path.str();
+}
+
 /// Hexagon Toolchain
 
 std::string HexagonToolChain::GetGnuDir(const std::string &InstalledDir,
                                         const ArgList &Args) {
   // Locate the rest of the toolchain ...
   std::string GccToolchain = getGCCToolchainDir(Args);
 
   if (!GccToolchain.empty())

cfe/trunk/lib/Driver/Tools.h

enum class FloatABI {
   Soft,
   Hard,
 };
 
 NanEncoding getSupportedNanEncoding(StringRef &CPU);
 void getMipsCPUAndABI(const llvm::opt::ArgList &Args,
                       const llvm::Triple &Triple, StringRef &CPUName,
                       StringRef &ABIName);
+std::string getMipsABILibSuffix(const llvm::opt::ArgList &Args,
+                                const llvm::Triple &Triple);
 bool hasMipsAbiArg(const llvm::opt::ArgList &Args, const char *Value);
 bool isUCLibc(const llvm::opt::ArgList &Args);
 bool isNaN2008(const llvm::opt::ArgList &Args, const llvm::Triple &Triple);
 bool isFPXXDefault(const llvm::Triple &Triple, StringRef CPUName,
                    StringRef ABIName, mips::FloatABI FloatABI);
 bool shouldUseFPXX(const llvm::opt::ArgList &Args, const llvm::Triple &Triple,
                    StringRef CPUName, StringRef ABIName,
                    mips::FloatABI FloatABI);

cfe/trunk/lib/Driver/Tools.cpp

CPUName = llvm::StringSwitch<const char *>(ABIName)
                   .Cases("o32", "eabi", DefMips32CPU)
                   .Cases("n32", "n64", DefMips64CPU)
                   .Default("");
   }
 
   // FIXME: Warn on inconsistent use of -march and -mabi.
 }
 
+std::string mips::getMipsABILibSuffix(const ArgList &Args,
+                                      const llvm::Triple &Triple) {
+  StringRef CPUName, ABIName;
+  tools::mips::getMipsCPUAndABI(Args, Triple, CPUName, ABIName);
+  return llvm::StringSwitch<std::string>(ABIName)
+      .Case("o32", "")
+      .Case("n32", "32")
+      .Case("n64", "64");
+}
+
 // Convert ABI name to the GNU tools acceptable variant.
 static StringRef getGnuCompatibleMipsABIName(StringRef ABI) {
   return llvm::StringSwitch<llvm::StringRef>(ABI)
       .Case("o32", "32")
       .Case("n64", "64")
       .Default(ABI);
 }
 
if (A->getOption().matches(options::OPT_funsigned_char) ||
         A->getOption().matches(options::OPT_fno_signed_char)) {
       CmdArgs.push_back("-fno-signed-char");
     }
   } else if (!isSignedCharDefault(getToolChain().getTriple())) {
     CmdArgs.push_back("-fno-signed-char");
   }
 
   // -fuse-cxa-atexit is default.
-  if (!Args.hasFlag(options::OPT_fuse_cxa_atexit,
-                    options::OPT_fno_use_cxa_atexit,
-                    !IsWindowsCygnus && !IsWindowsGNU &&
-                    getToolChain().getTriple().getOS() != llvm::Triple::Solaris &&
-                    getToolChain().getArch() != llvm::Triple::hexagon &&
-                    getToolChain().getArch() != llvm::Triple::xcore) ||
+  if (!Args.hasFlag(
+          options::OPT_fuse_cxa_atexit, options::OPT_fno_use_cxa_atexit,
+              getToolChain().getArch() != llvm::Triple::xcore &&
+              getToolChain().getArch() != llvm::Triple::xcore &&
+              ((getToolChain().getTriple().getVendor() !=
+                llvm::Triple::MipsTechnologies) ||
+               getToolChain().getTriple().hasEnvironment())) ||
       KernelOrKext)
     CmdArgs.push_back("-fno-use-cxa-atexit");
 
   // -fms-extensions=0 is default.
   if (Args.hasFlag(options::OPT_fms_extensions, options::OPT_fno_ms_extensions,
                    IsWindowsMSVC))
     CmdArgs.push_back("-fms-extensions");
 
else if (Arch == llvm::Triple::arm || Arch == llvm::Triple::thumb) {
     // TODO: check which dynamic linker name.
     if (ToolChain.getTriple().getEnvironment() == llvm::Triple::GNUEABIHF ||
         arm::getARMFloatABI(ToolChain, Args) == arm::FloatABI::Hard)
       return "/lib/ld-linux-armhf.so.3";
     else
       return "/lib/ld-linux.so.3";
   } else if (Arch == llvm::Triple::mips || Arch == llvm::Triple::mipsel ||
              Arch == llvm::Triple::mips64 || Arch == llvm::Triple::mips64el) {
-    StringRef CPUName;
-    StringRef ABIName;
-    mips::getMipsCPUAndABI(Args, ToolChain.getTriple(), CPUName, ABIName);
-    bool IsNaN2008 = mips::isNaN2008(Args, ToolChain.getTriple());
-
-    StringRef LibDir = llvm::StringSwitch<llvm::StringRef>(ABIName)
-                           .Case("o32", "/lib")
-                           .Case("n32", "/lib32")
-                           .Case("n64", "/lib64")
-                           .Default("/lib");
+    std::string LibDir =
+        "/lib" + mips::getMipsABILibSuffix(Args, ToolChain.getTriple());
     StringRef LibName;
+    bool IsNaN2008 = mips::isNaN2008(Args, ToolChain.getTriple());
     if (mips::isUCLibc(Args))
       LibName = IsNaN2008 ? "ld-uClibc-mipsn8.so.0" : "ld-uClibc.so.0";
-    else
+    else if (!ToolChain.getTriple().hasEnvironment()) {
+      bool LE = (ToolChain.getTriple().getArch() == llvm::Triple::mipsel) ||
+                (ToolChain.getTriple().getArch() == llvm::Triple::mips64el);
+      LibName = LE ? "ld-musl-mipsel.so.1" : "ld-musl-mips.so.1";
+    } else
       LibName = IsNaN2008 ? "ld-linux-mipsn8.so.1" : "ld.so.1";
 
     return (LibDir + "/" + LibName).str();
   } else if (Arch == llvm::Triple::ppc)
     return "/lib/ld.so.1";
   else if (Arch == llvm::Triple::ppc64) {
     if (ppc::hasPPCAbiArg(Args, "elfv2"))
       return "/lib64/ld64.so.2";
void gnutools::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   llvm::Triple Triple = llvm::Triple(TripleStr);
 
   const llvm::Triple::ArchType Arch = ToolChain.getArch();
   const bool isAndroid =
       ToolChain.getTriple().getEnvironment() == llvm::Triple::Android;
   const bool IsPIE =
       !Args.hasArg(options::OPT_shared) && !Args.hasArg(options::OPT_static) &&
       (Args.hasArg(options::OPT_pie) || ToolChain.isPIEDefault());
+  const bool HasCRTBeginEndFiles =
+      ToolChain.getTriple().hasEnvironment() ||
+      (ToolChain.getTriple().getVendor() != llvm::Triple::MipsTechnologies);
 
   ArgStringList CmdArgs;
 
   // Silence warning for "clang -g foo.o -o foo"
   Args.ClaimAllArgs(options::OPT_g_Group);
   // and "clang -emit-llvm foo.o -o foo"
   Args.ClaimAllArgs(options::OPT_emit_llvm);
   // and for "clang -w foo.o -o foo". Other warning options are already
   // handled somewhere else.
   Args.ClaimAllArgs(options::OPT_w);
 
+  if (llvm::sys::path::filename(ToolChain.Linker) == "lld") {
+    CmdArgs.push_back("-flavor");
+    CmdArgs.push_back("gnu");
+    CmdArgs.push_back("-target");
+    CmdArgs.push_back(Args.MakeArgString(getToolChain().getTripleString()));
+  }
+
   if (!D.SysRoot.empty())
     CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
 
   if (IsPIE)
     CmdArgs.push_back("-pie");
 
   if (Args.hasArg(options::OPT_rdynamic))
     CmdArgs.push_back("-export-dynamic");
if (!Args.hasArg(options::OPT_nostdlib) &&
     if (Args.hasArg(options::OPT_static))
       crtbegin = isAndroid ? "crtbegin_static.o" : "crtbeginT.o";
     else if (Args.hasArg(options::OPT_shared))
       crtbegin = isAndroid ? "crtbegin_so.o" : "crtbeginS.o";
     else if (IsPIE)
       crtbegin = isAndroid ? "crtbegin_dynamic.o" : "crtbeginS.o";
     else
       crtbegin = isAndroid ? "crtbegin_dynamic.o" : "crtbegin.o";
+
+    if (HasCRTBeginEndFiles)
       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtbegin)));
 
     // Add crtfastmath.o if available and fast math is enabled.
     ToolChain.AddFastMathRuntimeIfAvailable(Args, CmdArgs);
   }
 
   Args.AddAllArgs(CmdArgs, options::OPT_L);
   Args.AddAllArgs(CmdArgs, options::OPT_u);
 
if (!Args.hasArg(options::OPT_nostartfiles)) {
       const char *crtend;
       if (Args.hasArg(options::OPT_shared))
         crtend = isAndroid ? "crtend_so.o" : "crtendS.o";
       else if (IsPIE)
         crtend = isAndroid ? "crtend_android.o" : "crtendS.o";
       else
         crtend = isAndroid ? "crtend_android.o" : "crtend.o";
 
+      if (HasCRTBeginEndFiles)
         CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtend)));
       if (!isAndroid)
         CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
     }
-  }
+  } else if (Args.hasArg(options::OPT_rtlib_EQ))
+    AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
 
   C.addCommand(llvm::make_unique<Command>(JA, *this, ToolChain.Linker.c_str(),
                                           CmdArgs, Inputs));
 }
 
 // NaCl ARM assembly (inline or standalone) can be written with a set of macros
 // for the various SFI requirements like register masking. The assembly tool
 // inserts the file containing the macros as an input into all the assembly

cfe/trunk/test/Driver/mips-mti-linux.c

+// Check frontend and linker invocations on GPL-free MIPS toolchain.
+//
+// FIXME: Using --sysroot with this toolchain/triple isn't supported. We use
+//        it here to test that we are producing the correct paths/flags.
+//        Ideally, we'd like to have an --llvm-toolchain option similar to
+//        the --gcc-toolchain one.
+
+// = Big-endian, mips32r2, hard float
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     --target=mips-mti-linux -mips32r2 -mhard-float \
+// RUN:     --sysroot=%S/Inputs/mips_mti_linux/sysroot \
+// RUN:   | FileCheck --check-prefix=CHECK-BE-HF-32R2 %s
+//
+// CHECK-BE-HF-32R2: "{{.*}}clang" {{.*}} "-triple" "mips-mti-linux"
+// CHECK-BE-HF-32R2-SAME: "-fuse-init-array" "-target-cpu" "mips32r2"
+// CHECK-BE-HF-32R2-SAME: "-isysroot" "{{.*}}mips_mti_linux/sysroot"
+// CHECK-BE-HF-32R2: "lld" "-flavor" "gnu" "-target" "mips-mti-linux"
+// CHECK-BE-HF-32R2-SAME: "--sysroot=[[SYSROOT:[^"]+]]" {{.*}} "-dynamic-linker" "/lib/ld-musl-mips.so.1"
+// CHECK-BE-HF-32R2-SAME: "[[SYSROOT]]/mips-r2-hard-musl/usr/lib/crt1.o"
+// CHECK-BE-HF-32R2-SAME: "[[SYSROOT]]/mips-r2-hard-musl/usr/lib/crti.o"
+// CHECK-BE-HF-32R2-SAME: "-L[[SYSROOT]]/mips-r2-hard-musl/usr/lib"
+// CHECK-BE-HF-32R2-SAME: "{{[^"]+}}/mips-r2-hard-musl/lib/linux/libclang_rt.builtins-mips.a"
+// CHECK-BE-HF-32R2-SAME: "-lc"
+// CHECK-BE-HF-32R2-SAME: "[[SYSROOT]]/mips-r2-hard-musl/usr/lib/crtn.o"
+
+// = Little-endian, mips32r2, hard float
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     --target=mips-mti-linux -mips32r2 -EL -mhard-float \
+// RUN:     --sysroot=%S/Inputs/mips_mti_linux/sysroot \
+// RUN:   | FileCheck --check-prefix=CHECK-LE-HF-32R2 %s
+//
+// CHECK-LE-HF-32R2: "{{.*}}clang" {{.*}} "-triple" "mipsel-mti-linux"
+// CHECK-LE-HF-32R2-SAME: "-fuse-init-array" "-target-cpu" "mips32r2"
+// CHECK-LE-HF-32R2-SAME: "-isysroot" "{{.*}}mips_mti_linux/sysroot"
+// CHECK-LE-HF-32R2: "lld" "-flavor" "gnu" "-target" "mipsel-mti-linux"
+// CHECK-LE-HF-32R2-SAME: "--sysroot=[[SYSROOT:[^"]+]]" {{.*}} "-dynamic-linker" "/lib/ld-musl-mipsel.so.1"
+// CHECK-LE-HF-32R2-SAME: "[[SYSROOT]]/mipsel-r2-hard-musl/usr/lib/crt1.o"
+// CHECK-LE-HF-32R2-SAME: "[[SYSROOT]]/mipsel-r2-hard-musl/usr/lib/crti.o"
+// CHECK-LE-HF-32R2-SAME: "-L[[SYSROOT]]/mipsel-r2-hard-musl/usr/lib"
+// CHECK-LE-HF-32R2-SAME: "{{[^"]+}}/mipsel-r2-hard-musl/lib/linux/libclang_rt.builtins-mipsel.a"
+// CHECK-LE-HF-32R2-SAME: "-lc"
+// CHECK-LE-HF-32R2-SAME: "[[SYSROOT]]/mipsel-r2-hard-musl/usr/lib/crtn.o"