[MSP430] Align the toolchain definition with the TI's msp430-gcc v9.2.0

[atrosinenko]

Summary

This patch updates the toolchain description for MSP430 target, aligning it with the TI-provided sysroot based on msp430-gcc v9.2.0.

It leaves some features (such as sanitizer runtimes, LTO, etc.) unsupported, trying to translate the remaining parts of the link_command spec description from current GCC version as closely as possible.

It introduces support for GCC -msim option to Clang that simplifies building msp430 binaries to be run on a simulator (such as for unit testing purposes).

This patch contains updated unit tests to prevent silent changing of the behavior. Its current behavior can be manually tested as follows:

• Compile and run on the simulator: compiles successfully, runs as expected, terminates cleanly

$ /path/to/bin/clang -target msp430 --sysroot=$sysroot test.c -o test -msim
$ $sysroot/bin/msp430-elf-run ./test
N = 1

• Compile for a real MCU: links successfully, can be run with MSP430 Emulator after manually setting pc to address written at the reset vector (0xFFFE)

$ /path/to/bin/clang -target msp430 --sysroot=$sysroot -mmcu=msp430g2553 blink.c -o blink -I $sysroot/include

Please note that in the latter case msp430-elf-gcc requires -I... option as well.

Current state:

• can run simple programs on a simulator built into msp430-elf-gdb
• can link a program by passing just a --sysroot=/path/to/msp430-gcc/binary/distrib
• tested on third-party MSP430 Emulator, see above
• not tested on a real hardware
• may require further adjustment of --gcc-toolchain option handling

test.c

#include <stdio.h>

int main()
{
  printf("N = %d\n", 1);
  return 0;
}

References:

• https://clang.llvm.org/docs/CrossCompilation.html
• https://www.ti.com/tool/MSP430-GCC-OPENSOURCE
• Old mail list discussion: --sysroot and --gcc-toolchain: any docs etc.?

[atrosinenko]

fix unit test: add another "-lgcc" and (hopefully) fix path separators on Windows

[atrosinenko]

Fix test once again (replace more literal slashes with regex).

[krisb]

clang/lib/Driver/ToolChains/MSP430.cpp

163

Seems the driver stops adding msp430-elf/include to the default include search paths, instead it adds $sysroot/include (or $gcc-toolchain/include). As I can see the latter isn't among the default include paths used by TI gcc.
So, shouldn't we change here to llvm::sys::path::append(Dir, "msp430-elf", "include"); as well?

247

What about an early exit here?

clang/test/Driver/msp430-toolchain.c

75–115

How about using a single run line with just --check-prefixes=DEFAULT-POS,DEFAULT-NEG?

100

Same here about --check-prefixes

[atrosinenko]

Thank you for the comments. Will send an update soon.

clang/lib/Driver/ToolChains/MSP430.cpp

163

Frankly speaking, I was more concerned with linker arguments autodiscovery. Adding $sysroot/msp430-elf/include definitely makes sense because that directory contains standard headers.

247

Agree, this would make this code clearer.

clang/test/Driver/msp430-toolchain.c

75–115

My goal was to ensure everything marked with DEFAULT-POS exists in the input stream. At the same time, none of patterns marked with DEFAULT-NEG should exist there.

It would be great to check this in a single run (at least, there would be no chance to run the compiler process twice with slightly different arguments by mistake). From reading the FileCheck documentation it is not very clear the precise semantics of --check-prefixes=A,B. Experimenting with it shows it really behaves not in a way I need here.

test.txt

POS: A
POS: B
NEG-NOT: 1
NEG-NOT: 2

FileCheck test.txt --check-prefixes=POS,NEG does fail for the following input:

A
B
1

as expected. On the other hand, the following is considered OK:

A
1
B

As I understand, when an option --check-prefixes=POS,NEG is given to FileCheck, it just recognizes both prefixes but it uses them in the same pass.

What can really help here is --implicit-check-not. According to the same documentation, it does precisely what I need but requires specifying every forbidden pattern in the command line.

Another possibility that I prefer would be to rewrite it like this:

// RUN: %clang %s -### -no-canonical-prefixes -target msp430 --sysroot="" > %t 2>&1
// RUN: FileCheck --check-prefix=DEFAULT-POS %s < %t
// RUN: FileCheck --check-prefix=DEFAULT-NEG %s < %t

This would still be slightly too verbose but at least the compiler arguments are specified only once and just a single clang process is spawned.

[atrosinenko]

Address the review comments.

Now include directories should be set in a much more similar way to msp430-gcc v8.3.1. The test was added as well. The most significant difference is that Clang adds one extra include directory: /path/to/build/dir/lib/clang/11.0.0/include. Hope this would not mess things up too much.

After adjusting the standard include directories, test programs for the simulator can be built with something like this

/path/to/clang -target msp430 --sysroot=$sysroot test.c -o test -msim

without specifying -I flag (just with msp430-elf-gcc).

Still, I am not sure this handles --sysroot and --gcc-toolchain exactly in the expected way. But at least it handles --sysroot=/path/to/distribution/from/TI as suggested in https://clang.llvm.org/docs/CrossCompilation.html

Meanwhile, while rewriting the msp430-toolchain.c to get rid of pairs of identical compiler invocations, I have found a forgotten ...-NEG case. :)

[atrosinenko]

Unit test: fix for path separators on Windows

[atrosinenko]

Meanwhile, msp430-gcc v9.2.0 was released on Jun 12. Will recheck against the new version slightly later.

[atrosinenko]

• Rebase onto an up-to-date upstream commit
• Recheck against v9.2.0
• Misc fixes and improvements

[krisb]

Thank you!
LGTM, except some minor nits below.

clang/lib/Driver/ToolChains/MSP430.cpp

154

I'd guard this by if (GCCInstallation.isValid()) to avoid adding include directories with relative paths if GCCInstallation.getInstallPath() is empty.

239

Is the check for fno-stack-protector necessary here? Looks as the checks for 'positive' options should be enough to do the trick.

clang/test/Driver/msp430-toolchain.c

5

This way looks okay to me, but I believe you should be able to check cc1 command (though -###) for -internal-isystem, right?

[atrosinenko]

clang/lib/Driver/ToolChains/MSP430.cpp

154

Fixed.

239

While the "negative" option is not mentioned at all by the specs:

$ msp430-elf-gcc -dumpspecs | grep stack-protector
%{fstack-protector|fstack-protector-all|fstack-protector-strong|fstack-protector-explicit:-lssp_nonshared -lssp}

it seems these options are already basically preprocessed by gcc driver:

$ msp430-elf-gcc -### empty.o 2>&1 | grep -Eo " -l[a-z_0-9]*" | tr "\n" " "
 -lgcc  -lmul_none  -lc  -lgcc  -lcrt  -lnosys  -lgcc  -lgcc
$ msp430-elf-gcc -### empty.o -fstack-protector 2>&1 | grep -Eo " -l[a-z_0-9]*" | tr "\n" " "
 -lssp_nonshared  -lssp  -lgcc  -lmul_none  -lc  -lgcc  -lcrt  -lnosys  -lgcc  -lgcc
$ msp430-elf-gcc -### empty.o -fstack-protector -fno-stack-protector 2>&1 | grep -Eo " -l[a-z_0-9]*" | tr "\n" " "
 -lgcc  -lmul_none  -lc  -lgcc  -lcrt  -lnosys  -lgcc  -lgcc

and they seem to have the usual semantics of "the last one takes effect".

clang/test/Driver/msp430-toolchain.c

5

It works, thank you! Will wait for unit test results on Windows.

[atrosinenko]

Address the review comments.

[atrosinenko]

Fix path separators in unit test on Windows

[atrosinenko]

Just add the test on -rtlib=compiler-rt handling as everything other is ready for basic clang_rt.builtins support.

[atrosinenko]

Just an automatic rebase to (possibly) fix failing "Apply patch" step.

[krisb]

Sorry for the delays in response, busy days.
LGTM, thanks!

[atrosinenko]

Thank you! Will probably land it tomorrow.

[atrosinenko]

After a final retesting, this patch was updated a bit.

[stellaraccident]

The msp430-toolchain.c test was failing in our setup, and I've put together a fix in D84058.

clang/include/clang/Driver/Options.td

 def mconstant_cfstrings : Flag<["-"], "mconstant-cfstrings">, Group<clang_ignored_m_Group>;
 def mconsole : Joined<["-"], "mconsole">, Group<m_Group>, Flags<[DriverOption]>;
 def mwindows : Joined<["-"], "mwindows">, Group<m_Group>, Flags<[DriverOption]>;
 def mdll : Joined<["-"], "mdll">, Group<m_Group>, Flags<[DriverOption]>;
 def municode : Joined<["-"], "municode">, Group<m_Group>, Flags<[DriverOption]>;
 def mthreads : Joined<["-"], "mthreads">, Group<m_Group>, Flags<[DriverOption]>;
 def mcpu_EQ : Joined<["-"], "mcpu=">, Group<m_Group>;
 def mmcu_EQ : Joined<["-"], "mmcu=">, Group<m_Group>;
+def msim : Flag<["-"], "msim">, Group<m_Group>;
 def mdynamic_no_pic : Joined<["-"], "mdynamic-no-pic">, Group<m_Group>;
 def mfix_and_continue : Flag<["-"], "mfix-and-continue">, Group<clang_ignored_m_Group>;
 def mieee_fp : Flag<["-"], "mieee-fp">, Group<clang_ignored_m_Group>;
 def minline_all_stringops : Flag<["-"], "minline-all-stringops">, Group<clang_ignored_m_Group>;
 def mno_inline_all_stringops : Flag<["-"], "mno-inline-all-stringops">, Group<clang_ignored_m_Group>;
 def malign_double : Flag<["-"], "malign-double">, Group<m_Group>, Flags<[CC1Option]>,
   HelpText<"Align doubles to two words in structs (x86 only)">;
 def mfloat_abi_EQ : Joined<["-"], "mfloat-abi=">, Group<m_Group>, Values<"soft,softfp,hard">;
def mlvi_hardening : Flag<["-"], "mlvi-hardening">, Group<m_Group>, Flags<[CoreOption,DriverOption]>,
   HelpText<"Enable all mitigations for Load Value Injection (LVI)">;
 def mno_lvi_hardening : Flag<["-"], "mno-lvi-hardening">, Group<m_Group>, Flags<[CoreOption,DriverOption]>,
   HelpText<"Disable mitigations for Load Value Injection (LVI)">;
 def mlvi_cfi : Flag<["-"], "mlvi-cfi">, Group<m_Group>, Flags<[CoreOption,DriverOption]>,
   HelpText<"Enable only control-flow mitigations for Load Value Injection (LVI)">;
 def mno_lvi_cfi : Flag<["-"], "mno-lvi-cfi">, Group<m_Group>, Flags<[CoreOption,DriverOption]>,
   HelpText<"Disable control-flow mitigations for Load Value Injection (LVI)">;
 
-def mrelax : Flag<["-"], "mrelax">, Group<m_riscv_Features_Group>,
+def mrelax : Flag<["-"], "mrelax">, Group<m_Group>,
   HelpText<"Enable linker relaxation">;
-def mno_relax : Flag<["-"], "mno-relax">, Group<m_riscv_Features_Group>,
+def mno_relax : Flag<["-"], "mno-relax">, Group<m_Group>,
   HelpText<"Disable linker relaxation">;
 def msmall_data_limit_EQ : Joined<["-"], "msmall-data-limit=">, Group<m_Group>,
   Alias<G>,
   HelpText<"Put global and static data smaller than the limit into a special section">;
 def msave_restore : Flag<["-"], "msave-restore">, Group<m_riscv_Features_Group>,
   HelpText<"Enable using library calls for save and restore">;
 def mno_save_restore : Flag<["-"], "mno-save-restore">, Group<m_riscv_Features_Group>,
   HelpText<"Disable using library calls for save and restore">;

clang/lib/Basic/Targets/MSP430.cpp

 ArrayRef<const char *> MSP430TargetInfo::getGCCRegNames() const {
   return llvm::makeArrayRef(GCCRegNames);
 }
 
 void MSP430TargetInfo::getTargetDefines(const LangOptions &Opts,
                                         MacroBuilder &Builder) const {
   Builder.defineMacro("MSP430");
   Builder.defineMacro("__MSP430__");
+  Builder.defineMacro("__ELF__");
   // FIXME: defines for different 'flavours' of MCU
 }

clang/lib/Driver/ToolChains/Gnu.cpp

if (AndroidArmMultilibs.select(Flags, Result.SelectedMultilib))
     Result.Multilibs = AndroidArmMultilibs;
 }
 
 static bool findMSP430Multilibs(const Driver &D,
                                 const llvm::Triple &TargetTriple,
                                 StringRef Path, const ArgList &Args,
                                 DetectedMultilibs &Result) {
   FilterNonExistent NonExistent(Path, "/crtbegin.o", D.getVFS());
-  Multilib MSP430Multilib = makeMultilib("/430");
+  Multilib WithoutExceptions = makeMultilib("/430").flag("-exceptions");
+  Multilib WithExceptions = makeMultilib("/430/exceptions").flag("+exceptions");
+
   // FIXME: when clang starts to support msp430x ISA additional logic
   // to select between multilib must be implemented
   // Multilib MSP430xMultilib = makeMultilib("/large");
 
-  Result.Multilibs.push_back(MSP430Multilib);
+  Result.Multilibs.push_back(WithoutExceptions);
+  Result.Multilibs.push_back(WithExceptions);
   Result.Multilibs.FilterOut(NonExistent);
 
   Multilib::flags_list Flags;
+  addMultilibFlag(Args.hasFlag(options::OPT_fexceptions,
+                               options::OPT_fno_exceptions, false),
+                  "exceptions", Flags);
   if (Result.Multilibs.select(Flags, Result.SelectedMultilib))
     return true;
 
   return false;
 }
 
 static void findRISCVBareMetalMultilibs(const Driver &D,
                                         const llvm::Triple &TargetTriple,

clang/lib/Driver/ToolChains/MSP430.h

public:
   void addClangTargetOptions(const llvm::opt::ArgList &DriverArgs,
                              llvm::opt::ArgStringList &CC1Args,
                              Action::OffloadKind) const override;
 
   bool isPICDefault() const override { return false; }
   bool isPIEDefault() const override { return false; }
   bool isPICDefaultForced() const override { return true; }
 
+  UnwindLibType
+  GetUnwindLibType(const llvm::opt::ArgList &Args) const override {
+    return UNW_None;
+  }
+
 protected:
   Tool *buildLinker() const override;
 
 private:
   std::string computeSysRoot() const override;
 };
 
 } // end namespace toolchains
 
 namespace tools {
 namespace msp430 {
 
 class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
   Linker(const ToolChain &TC) : Tool("MSP430::Linker", "msp430-elf-ld", TC) {}
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
+
+private:
+  void AddStartFiles(bool UseExceptions, const llvm::opt::ArgList &Args,
+                     llvm::opt::ArgStringList &CmdArgs) const;
+  void AddDefaultLibs(const llvm::opt::ArgList &Args,
+                      llvm::opt::ArgStringList &CmdArgs) const;
+  void AddEndFiles(bool UseExceptions, const llvm::opt::ArgList &Args,
+                   llvm::opt::ArgStringList &CmdArgs) const;
 };
 
 void getMSP430TargetFeatures(const Driver &D, const llvm::opt::ArgList &Args,
                              std::vector<llvm::StringRef> &Features);
 } // end namespace msp430
 } // end namespace tools
 } // end namespace driver
 } // end namespace clang
 
 #endif // LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_MSP430_H

clang/lib/Driver/ToolChains/MSP430.cpp

if (GCCInstallation.isValid()) {
 
     SmallString<128> GCCRtPath;
     llvm::sys::path::append(GCCRtPath,
                             GCCInstallation.getInstallPath(), MultilibSuf);
     addPathIfExists(D, GCCRtPath, getFilePaths());
   }
 
   SmallString<128> SysRootDir(computeSysRoot());
-  llvm::sys::path::append(SysRootDir, "lib", MultilibSuf);
+  llvm::sys::path::append(SysRootDir, "msp430-elf", "lib", MultilibSuf);
   addPathIfExists(D, SysRootDir, getFilePaths());
 }
 
 std::string MSP430ToolChain::computeSysRoot() const {
   if (!getDriver().SysRoot.empty())
     return getDriver().SysRoot;
 
   SmallString<128> Dir;
   if (GCCInstallation.isValid())
-    llvm::sys::path::append(Dir, GCCInstallation.getParentLibPath(), "..",
-                            GCCInstallation.getTriple().str());
+    llvm::sys::path::append(Dir, GCCInstallation.getParentLibPath(), "..");
   else
-    llvm::sys::path::append(Dir, getDriver().Dir, "..", getTriple().str());
+    llvm::sys::path::append(Dir, getDriver().Dir, "..");
 
   return std::string(Dir.str());
 }
 
 void MSP430ToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
                                                 ArgStringList &CC1Args) const {
   if (DriverArgs.hasArg(options::OPT_nostdinc) ||
       DriverArgs.hasArg(options::OPT_nostdlibinc))
     return;
 
+  SmallString<128> MultilibInclude(GCCInstallation.getInstallPath());
+  llvm::sys::path::append(MultilibInclude, "include");
+  addSystemInclude(DriverArgs, CC1Args, MultilibInclude.str());
+
+  SmallString<128> MultilibFixedInclude(GCCInstallation.getInstallPath());
+  llvm::sys::path::append(MultilibFixedInclude, "include-fixed");
+  addSystemInclude(DriverArgs, CC1Args, MultilibFixedInclude.str());
+
   SmallString<128> Dir(computeSysRoot());
-  llvm::sys::path::append(Dir, "include");
+  llvm::sys::path::append(Dir, "msp430-elf", "include");
   addSystemInclude(DriverArgs, CC1Args, Dir.str());
 }
 
 void MSP430ToolChain::addClangTargetOptions(const ArgList &DriverArgs,
                                             ArgStringList &CC1Args,
                                             Action::OffloadKind) const {
   CC1Args.push_back("-nostdsysteminc");
 
if (MCU.startswith("msp430i")) {
     CC1Args.push_back(DriverArgs.MakeArgString("-D__" + MCU.upper() + "__"));
   }
 }
 
 Tool *MSP430ToolChain::buildLinker() const {
   return new tools::msp430::Linker(*this);
 }
 
+void msp430::Linker::AddStartFiles(bool UseExceptions, const ArgList &Args,
+                                   ArgStringList &CmdArgs) const {
+  const ToolChain &ToolChain = getToolChain();
+
+  const char *crt0 = Args.hasArg(options::OPT_pg) ? "gcrt0.o" : "crt0.o";
+  CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crt0)));
+  const char *crtbegin = UseExceptions ? "crtbegin.o" : "crtbegin_no_eh.o";
+  CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtbegin)));
+}
+
+void msp430::Linker::AddDefaultLibs(const llvm::opt::ArgList &Args,
+                                    llvm::opt::ArgStringList &CmdArgs) const {
+  const ToolChain &ToolChain = getToolChain();
+  const Driver &D = ToolChain.getDriver();
+
+  CmdArgs.push_back("--start-group");
+  CmdArgs.push_back(Args.MakeArgString(getHWMultLib(Args)));
+  CmdArgs.push_back("-lc");
+  AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
+  CmdArgs.push_back("-lcrt");
+
+  if (Args.hasArg(options::OPT_msim)) {
+    CmdArgs.push_back("-lsim");
+
+    // msp430-sim.ld relies on __crt0_call_exit being implicitly .refsym-ed
+    // in main() by msp430-gcc.
+    // This workaround should work seamlessly unless the compilation unit that
+    // contains main() is compiled by clang and then passed to
+    // gcc compiler driver for linkage.
+    CmdArgs.push_back("--undefined=__crt0_call_exit");
+  } else
+    CmdArgs.push_back("-lnosys");
+
+  CmdArgs.push_back("--end-group");
+  AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
+}
+
+void msp430::Linker::AddEndFiles(bool UseExceptions, const ArgList &Args,
+                                 ArgStringList &CmdArgs) const {
+  const ToolChain &ToolChain = getToolChain();
+  const Driver &D = ToolChain.getDriver();
+
+  const char *crtend = UseExceptions ? "crtend.o" : "crtend_no_eh.o";
+  CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtend)));
+  AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
+}
+
+static void AddSspArgs(const ArgList &Args, ArgStringList &CmdArgs) {
+  Arg *SspFlag = Args.getLastArg(
+      options::OPT_fno_stack_protector, options::OPT_fstack_protector,
+      options::OPT_fstack_protector_all, options::OPT_fstack_protector_strong);
+
+  if (SspFlag &&
+      !SspFlag->getOption().matches(options::OPT_fno_stack_protector)) {
+    CmdArgs.push_back("-lssp_noshared");
+    CmdArgs.push_back("-lssp");
+  }
+}
+
+static void AddImplicitLinkerScript(const std::string SysRoot,
+                                    const ArgList &Args,
+                                    ArgStringList &CmdArgs) {
+  if (Args.hasArg(options::OPT_T))
+    return;
+
+  if (Args.hasArg(options::OPT_msim)) {
+    CmdArgs.push_back("-Tmsp430-sim.ld");
+    return;
+  }
+
+  const Arg *MCUArg = Args.getLastArg(options::OPT_mmcu_EQ);
+  if (!MCUArg)
+    return;
+
+  SmallString<128> MCULinkerScriptPath(SysRoot);
+  llvm::sys::path::append(MCULinkerScriptPath, "include");
+  // -L because <mcu>.ld INCLUDEs <mcu>_symbols.ld
+  CmdArgs.push_back(Args.MakeArgString("-L" + MCULinkerScriptPath));
+  CmdArgs.push_back(
+      Args.MakeArgString("-T" + StringRef(MCUArg->getValue()) + ".ld"));
+}
+
 void msp430::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                   const InputInfo &Output,
                                   const InputInfoList &Inputs,
                                   const ArgList &Args,
                                   const char *LinkingOutput) const {
   const ToolChain &ToolChain = getToolChain();
   const Driver &D = ToolChain.getDriver();
   std::string Linker = ToolChain.GetProgramPath(getShortName());
   ArgStringList CmdArgs;
+  bool UseExceptions = Args.hasFlag(options::OPT_fexceptions,
+                                    options::OPT_fno_exceptions, false);
+  bool UseStartAndEndFiles = !Args.hasArg(options::OPT_nostdlib, options::OPT_r,
+                                          options::OPT_nostartfiles);
+
+  if (Args.hasArg(options::OPT_mrelax))
+    CmdArgs.push_back("--relax");
+  if (!Args.hasArg(options::OPT_r, options::OPT_g_Group))
+    CmdArgs.push_back("--gc-sections");
+
+  Args.AddAllArgs(CmdArgs, {
+                               options::OPT_e,
+                               options::OPT_n,
+                               options::OPT_s,
+                               options::OPT_t,
+                               options::OPT_u,
+                           });
 
-  if (!D.SysRoot.empty())
-    CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
+  if (UseStartAndEndFiles)
+    AddStartFiles(UseExceptions, Args, CmdArgs);
 
   Args.AddAllArgs(CmdArgs, options::OPT_L);
   ToolChain.AddFilePathLibArgs(Args, CmdArgs);
+  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
 
-  if (!Args.hasArg(options::OPT_T)) {
-    if (const Arg *MCUArg = Args.getLastArg(options::OPT_mmcu_EQ))
-      CmdArgs.push_back(
-          Args.MakeArgString("-T" + StringRef(MCUArg->getValue()) + ".ld"));
-  } else {
-    Args.AddAllArgs(CmdArgs, options::OPT_T);
+  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_r,
+                   options::OPT_nodefaultlibs)) {
+    AddSspArgs(Args, CmdArgs);
+    AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
+    if (!Args.hasArg(options::OPT_nolibc)) {
+      AddDefaultLibs(Args, CmdArgs);
+      AddImplicitLinkerScript(D.SysRoot, Args, CmdArgs);
     }
-
-  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
-    CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt0.o")));
-    CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtbegin.o")));
   }
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
+  if (UseStartAndEndFiles)
+    AddEndFiles(UseExceptions, Args, CmdArgs);
 
-  CmdArgs.push_back("--start-group");
-  CmdArgs.push_back(Args.MakeArgString(getHWMultLib(Args)));
-  CmdArgs.push_back("-lgcc");
-  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
-    CmdArgs.push_back("-lc");
-    CmdArgs.push_back("-lcrt");
-    CmdArgs.push_back("-lnosys");
-  }
-  CmdArgs.push_back("--end-group");
-
-  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
-    CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
-    CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
-  }
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
+
+  Args.AddAllArgs(CmdArgs, options::OPT_T);
+
   C.addCommand(
       std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileCurCP(),
                                 Args.MakeArgString(Linker), CmdArgs, Inputs));
 }

clang/test/Driver/msp430-toolchain.c

-// A basic clang -cc1 command-line, and simple environment check.
+// Tests for the toolchain description for msp430-gcc
+// Splitting some tests into POS and NEG parts so the latter can validate
+// output fragments as large as possible for absence of some text.
+
+// Test for include paths (cannot use -###)
+
+// RUN: %clang %s -v -no-canonical-prefixes -target msp430 -E -o /dev/null \
+// RUN:   --sysroot="%S/Inputs/basic_msp430_tree" 2>&1 \
+// RUN:   | FileCheck -check-prefix=INCLUDE-DIRS %s
+// INCLUDE-DIRS: "{{.*}}clang{{.*}}" -cc1 -triple msp430
+// INCLUDE-DIRS: #include <...> search starts here:
+// INCLUDE-DIRS: {{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1{{[/\\]}}include
+// INCLUDE-DIRS: {{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1{{[/\\]}}include-fixed
+// INCLUDE-DIRS: {{.*}}/Inputs/basic_msp430_tree{{[/\\]}}msp430-elf{{[/\\]}}include
+// INCLUDE-DIRS: End of search list.
+
+// Tests for passing flags to msp430-elf-ld (not file-related)
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 --sysroot="" > %t 2>&1
+// RUN: FileCheck -check-prefix=DEFAULT-POS %s < %t
+// RUN: FileCheck -check-prefix=DEFAULT-NEG %s < %t
+// DEFAULT-POS: clang{{.*}} "-cc1" "-triple" "msp430"
+// DEFAULT-POS: "{{.*}}msp430-elf-ld"
+// DEFAULT-POS: "--gc-sections"
+// DEFAULT-NEG-NOT: "--relax"
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 --sysroot="" \
+// RUN:   -r 2>&1 | FileCheck --check-prefixes=NO-GC-SECTIONS,RELOCATABLE-OBJECT %s
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 --sysroot="" \
+// RUN:   -g 2>&1 | FileCheck -check-prefix=NO-GC-SECTIONS %s
+// NO-GC-SECTIONS: "{{.*}}msp430-elf-ld"
+// NO-GC-SECTIONS-NOT: "--gc-sections"
+// RELOCATABLE-OBJECT-NOT: crt0.o
+// RELOCATABLE-OBJECT-NOT: crtbegin
+// RELOCATABLE-OBJECT-NOT: crtend
+// RELOCATABLE-OBJECT-NOT: "-l{{.*}}"
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 --sysroot="" \
+// RUN:   -Wl,--some-linker-arg 2>&1 | FileCheck -check-prefix=WL-ARG %s
+// WL-ARG: "{{.*}}msp430-elf-ld"
+// WL-ARG: "--some-linker-arg"
+
+// Trivially mapped options: arbitrarily split into two disjoint groups
+// to check both "on"/present and "off"/absent state (when appropriate).
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 --sysroot="" \
+// RUN:   -o /tmp/test.elf -r -t -z muldefs -mrelax > %t 2>&1
+// RUN: FileCheck -check-prefix=MISC-FLAGS-1-POS %s < %t
+// RUN: FileCheck -check-prefix=MISC-FLAGS-1-NEG %s < %t
+// MISC-FLAGS-1-POS: "{{.*}}msp430-elf-ld"
+// MISC-FLAGS-1-POS-DAG: "--relax"
+// MISC-FLAGS-1-POS-DAG: "-o" "/tmp/test.elf"
+// MISC-FLAGS-1-POS-DAG: "-r"
+// MISC-FLAGS-1-POS-DAG: "-t"
+// MISC-FLAGS-1-POS-DAG: "-z" "muldefs"
+// MISC-FLAGS-1-NEG: "{{.*}}msp430-elf-ld"
+// MISC-FLAGS-1-NEG-NOT: "-e{{.*}}"
+// MISC-FLAGS-1-NEG-NOT: "-s"
+// MISC-FLAGS-1-NEG-NOT: "-u"
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 --sysroot="" \
+// RUN:   -e EntryPoint -s -u __undef > %t 2>&1
+// RUN: FileCheck -check-prefix=MISC-FLAGS-2-POS %s < %t
+// RUN: FileCheck -check-prefix=MISC-FLAGS-2-NEG %s < %t
+// MISC-FLAGS-2-POS: "{{.*}}msp430-elf-ld"
+// MISC-FLAGS-2-POS: "-e" "EntryPoint" "-s" "-u" "__undef"
+// MISC-FLAGS-2-NEG: "{{.*}}msp430-elf-ld"
+// MISC-FLAGS-2-NEG-NOT: "-r"
+// MISC-FLAGS-2-NEG-NOT: "-t"
+// MISC-FLAGS-2-NEG-NOT: "-z"
+// MISC-FLAGS-2-NEG-NOT: "--relax"
 
-// RUN: %clang %s -### -no-canonical-prefixes -target msp430 --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=CC1 %s
-// CC1: clang{{.*}} "-cc1" "-triple" "msp430"
+// Tests for -nostdlib, -nostartfiles, -nodefaultfiles and -f(no-)exceptions
 
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 \
-// RUN:   --gcc-toolchain=%S/Inputs/basic_msp430_tree --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430 %s
+// RUN:   --sysroot="%S/Inputs/basic_msp430_tree" > %t 2>&1
+// RUN: FileCheck -check-prefix=LIBS-DEFAULT-POS %s < %t
+// RUN: FileCheck -check-prefix=LIBS-DEFAULT-NEG %s < %t
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 \
+// RUN:   --gcc-toolchain="%S/Inputs/basic_msp430_tree" --sysroot="" 2>&1 \
+// RUN:   | FileCheck -check-prefix=LIBS-DEFAULT-GCC-TOOLCHAIN %s
+// LIBS-DEFAULT-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LIBS-DEFAULT-POS: "{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crt0.o"
+// LIBS-DEFAULT-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtbegin_no_eh.o"
+// LIBS-DEFAULT-POS: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430"
+// LIBS-DEFAULT-POS: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
+// LIBS-DEFAULT-POS: "-lgcc" "--start-group" "-lmul_none" "-lc" "-lgcc" "-lcrt" "-lnosys" "--end-group" "-lgcc"
+// LIBS-DEFAULT-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtend_no_eh.o" "-lgcc"
+// LIBS-DEFAULT-GCC-TOOLCHAIN: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LIBS-DEFAULT-GCC-TOOLCHAIN: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crt0.o"
+// LIBS-DEFAULT-GCC-TOOLCHAIN: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtbegin_no_eh.o"
+// LIBS-DEFAULT-GCC-TOOLCHAIN: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430"
+// LIBS-DEFAULT-GCC-TOOLCHAIN: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
+// LIBS-DEFAULT-GCC-TOOLCHAIN: "-lgcc" "--start-group" "-lmul_none" "-lc" "-lgcc" "-lcrt" "-lnosys" "--end-group"
+// LIBS-DEFAULT-GCC-TOOLCHAIN: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtend_no_eh.o" "-lgcc"
+// LIBS-DEFAULT-NEG-NOT: gcrt0.o
+// LIBS-DEFAULT-NEG-NOT: crtbegin.o
+// LIBS-DEFAULT-NEG-NOT: -lssp_nonshared
+// LIBS-DEFAULT-NEG-NOT: -lssp
+// LIBS-DEFAULT-NEG-NOT: crtend.o
+// LIBS-DEFAULT-NEG-NOT: /exceptions
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 -fexceptions \
+// RUN:   --sysroot="%S/Inputs/basic_msp430_tree" > %t 2>&1
+// RUN: FileCheck -check-prefix=LIBS-EXC-POS %s < %t
+// RUN: FileCheck -check-prefix=LIBS-EXC-NEG %s < %t
+// LIBS-EXC-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LIBS-EXC-POS: "{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430/exceptions{{/|\\\\}}crt0.o"
+// LIBS-EXC-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430/exceptions{{/|\\\\}}crtbegin.o"
+// LIBS-EXC-POS: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430/exceptions"
+// LIBS-EXC-POS: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430/exceptions"
+// LIBS-EXC-POS: "-lgcc" "--start-group" "-lmul_none" "-lc" "-lgcc" "-lcrt" "-lnosys" "--end-group"
+// LIBS-EXC-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430/exceptions{{/|\\\\}}crtend.o" "-lgcc"
+// LIBS-EXC-NEG-NOT: "{{.*}}/430"
+// LIBS-EXC-NEG-NOT: "{{.*}}430/crt{{.*}}"
 
-// MSP430: "{{.*}}Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
-// MSP430: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/430"
-// MSP430: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
-// MSP430: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crt0.o"
-// MSP430: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/430{{/|\\\\}}crtbegin.o"
-// MSP430: "--start-group" "-lmul_none" "-lgcc" "-lc" "-lcrt" "-lnosys" "--end-group"
-// MSP430: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/430{{/|\\\\}}crtend.o"
-// MSP430: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crtn.o"
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 \
+// RUN:   -fstack-protector  --sysroot="%S/Inputs/basic_msp430_tree" 2>&1 \
+// RUN:   | FileCheck -check-prefix=LIBS-SSP %s
+// LIBS-SSP: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LIBS-SSP: "{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crt0.o"
+// LIBS-SSP: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtbegin_no_eh.o"
+// LIBS-SSP: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430"
+// LIBS-SSP: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
+// LIBS-SSP: "-lssp_noshared" "-lssp"
+// LIBS-SSP: "-lgcc" "--start-group" "-lmul_none" "-lc" "-lgcc" "-lcrt" "-lnosys" "--end-group"
+// LIBS-SSP: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtend_no_eh.o" "-lgcc"
 
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -nodefaultlibs \
-// RUN:   --gcc-toolchain=%S/Inputs/basic_msp430_tree --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-NO-DFT-LIB %s
-
-// MSP430-NO-DFT-LIB: "{{.*}}Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
-// MSP430-NO-DFT-LIB: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/430"
-// MSP430-NO-DFT-LIB: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
-// MSP430-NO-DFT-LIB: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crt0.o"
-// MSP430-NO-DFT-LIB: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/430{{/|\\\\}}crtbegin.o"
-// MSP430-NO-DFT-LIB: "--start-group" "-lmul_none" "-lgcc" "--end-group"
-// MSP430-NO-DFT-LIB: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/430{{/|\\\\}}crtend.o"
-// MSP430-NO-DFT-LIB: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crtn.o"
+// RUN:   --sysroot="%S/Inputs/basic_msp430_tree" > %t 2>&1
+// RUN: FileCheck -check-prefix=LIBS-NO-DFT-POS %s < %t
+// RUN: FileCheck -check-prefix=LIBS-NO-DFT-NEG %s < %t
+// LIBS-NO-DFT-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LIBS-NO-DFT-POS: "{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crt0.o"
+// LIBS-NO-DFT-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtbegin_no_eh.o"
+// LIBS-NO-DFT-POS: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430"
+// LIBS-NO-DFT-POS: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
+// LIBS-NO-DFT-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtend_no_eh.o" "-lgcc"
+// LIBS-NO-DFT-NEG-NOT: "-lc"
+// LIBS-NO-DFT-NEG-NOT: "-lcrt"
+// LIBS-NO-DFT-NEG-NOT: "-lsim"
+// LIBS-NO-DFT-NEG-NOT: "-lnosys"
+// LIBS-NO-DFT-NEG-NOT: "--start-group"
+// LIBS-NO-DFT-NEG-NOT: "--end-group"
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 -nolibc \
+// RUN:   -fstack-protector --sysroot="%S/Inputs/basic_msp430_tree" > %t 2>&1
+// RUN: FileCheck -check-prefix=LIBS-NO-LIBC-POS %s < %t
+// RUN: FileCheck -check-prefix=LIBS-NO-LIBC-NEG %s < %t
+// LIBS-NO-LIBC-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LIBS-NO-LIBC-POS: "{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crt0.o"
+// LIBS-NO-LIBC-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtbegin_no_eh.o"
+// LIBS-NO-LIBC-POS: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430"
+// LIBS-NO-LIBC-POS: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
+// LIBS-NO-LIBC-POS: "-lssp_noshared" "-lssp" "-lgcc"
+// LIBS-NO-LIBC-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtend_no_eh.o" "-lgcc"
+// LIBS-NO-LIBC-NEG-NOT: "-lc"
+// LIBS-NO-LIBC-NEG-NOT: "-lcrt"
+// LIBS-NO-LIBC-NEG-NOT: "-lsim"
+// LIBS-NO-LIBC-NEG-NOT: "-lnosys"
+// LIBS-NO-LIBC-NEG-NOT: "--start-group"
+// LIBS-NO-LIBC-NEG-NOT: "--end-group"
 
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -nostartfiles \
-// RUN:   --gcc-toolchain=%S/Inputs/basic_msp430_tree --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-NO-START %s
-
-// MSP430-NO-START: "{{.*}}Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
-// MSP430-NO-START: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/430"
-// MSP430-NO-START: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
-// MSP430-NO-START: "--start-group" "-lmul_none" "-lgcc" "-lc" "-lcrt" "-lnosys" "--end-group"
+// RUN:   --sysroot="%S/Inputs/basic_msp430_tree" > %t 2>&1
+// RUN: FileCheck -check-prefix=LIBS-NO-START-POS %s < %t
+// RUN: FileCheck -check-prefix=LIBS-NO-START-NEG %s < %t
+// LIBS-NO-START-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LIBS-NO-START-POS: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430"
+// LIBS-NO-START-POS: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
+// LIBS-NO-START-POS: "-lgcc" "--start-group" "-lmul_none" "-lc" "-lgcc" "-lcrt" "-lnosys" "--end-group"
+// LIBS-NO-START-NEG-NOT: crt0.o
+// LIBS-NO-START-NEG-NOT: crtbegin
+// LIBS-NO-START-NEG-NOT: crtend
 
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -nostdlib \
-// RUN:   --gcc-toolchain=%S/Inputs/basic_msp430_tree --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-NO-STD-LIB %s
+// RUN:   --sysroot="%S/Inputs/basic_msp430_tree" > %t 2>&1
+// RUN: FileCheck -check-prefix=LIBS-NO-STD-POS %s < %t
+// RUN: FileCheck -check-prefix=LIBS-NO-STD-NEG %s < %t
+// LIBS-NO-STD-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LIBS-NO-STD-POS: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430"
+// LIBS-NO-STD-POS: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
+// LIBS-NO-STD-NEG-NOT: crt0.o
+// LIBS-NO-STD-NEG-NOT: crtbegin
+// LIBS-NO-STD-NEG-NOT: crtend
+// LIBS-NO-STD-NEG-NOT: "-lc"
+// LIBS-NO-STD-NEG-NOT: "-lcrt"
+// LIBS-NO-STD-NEG-NOT: "-lnosys"
+// LIBS-NO-STD-NEG-NOT: "--start-group"
+// LIBS-NO-STD-NEG-NOT: "--end-group"
+
+// Test for linker script autodiscovery
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mmcu=msp430g2553 \
+// RUN:   --sysroot=%S/Inputs/basic_msp430_tree 2>&1 \
+// RUN:   | FileCheck -check-prefix=LD-SCRIPT %s
+// LD-SCRIPT: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// LD-SCRIPT: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}include"
+// LD-SCRIPT: "-Tmsp430g2553.ld"
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mmcu=msp430g2553 \
+// RUN:   --sysroot=%S/Inputs/basic_msp430_tree \
+// RUN:   -T custom_script.ld 2>&1 \
+// RUN:   | FileCheck -check-prefix=CUSTOM-LD-SCRIPT %s
+// CUSTOM-LD-SCRIPT: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// CUSTOM-LD_SCRIPT-NOT: "-Tmsp430g2553.ld"
+// CUSTOM-LD-SCRIPT: "-T" "custom_script.ld"
+// CUSTOM-LD_SCRIPT-NOT: "-Tmsp430g2553.ld"
+
+// Test for compiling for simulator
+
+// RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mmcu=msp430g2553 \
+// RUN:   -msim --sysroot=%S/Inputs/basic_msp430_tree > %t 2>&1
+// RUN: FileCheck -check-prefix=SIMULATOR-POS %s < %t
+// RUN: FileCheck -check-prefix=SIMULATOR-NEG %s < %t
+// SIMULATOR-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
+// SIMULATOR-POS: "{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430{{/|\\\\}}crt0.o"
+// SIMULATOR-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtbegin_no_eh.o"
+// SIMULATOR-POS: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430"
+// SIMULATOR-POS: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
+// SIMULATOR-POS: "-lgcc" "--start-group" "-lmul_none" "-lc" "-lgcc" "-lcrt" "-lsim" "--undefined=__crt0_call_exit" "--end-group"
+// SIMULATOR-POS: "-Tmsp430-sim.ld"
+// SIMULATOR-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/430{{/|\\\\}}crtend_no_eh.o" "-lgcc"
+// SIMULATOR-NEG-NOT: "-lnosys"
 
-// MSP430-NO-STD-LIB: "{{.*}}Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
-// MSP430-NO-STD-LIB: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/430"
-// MSP430-NO-STD-LIB: "-L{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/7.3.1/../../..{{/|\\\\}}..{{/|\\\\}}msp430-elf{{/|\\\\}}lib/430"
-// MSP430-NO-STD-LIB: "--start-group" "-lmul_none" "-lgcc" "--end-group"
+// Tests for HWMult
 
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mmcu=msp430f147 --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-16BIT %s
+// RUN:   | FileCheck -check-prefix=HWMult-16BIT %s
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mmcu=msp430f147 -mhwmult=auto --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-16BIT %s
+// RUN:   | FileCheck -check-prefix=HWMult-16BIT %s
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mhwmult=16bit --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-16BIT %s
-
-// MSP430-HWMult-16BIT: "--start-group" "-lmul_16"
+// RUN:   | FileCheck -check-prefix=HWMult-16BIT %s
+// HWMult-16BIT: "--start-group" "-lmul_16"
 
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mmcu=msp430f4783 --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-32BIT %s
+// RUN:   | FileCheck -check-prefix=HWMult-32BIT %s
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mmcu=msp430f4783 -mhwmult=auto --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-32BIT %s
+// RUN:   | FileCheck -check-prefix=HWMult-32BIT %s
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mhwmult=32bit --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-32BIT %s
-
-// MSP430-HWMult-32BIT: "--start-group" "-lmul_32"
+// RUN:   | FileCheck -check-prefix=HWMult-32BIT %s
+// HWMult-32BIT: "--start-group" "-lmul_32"
 
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mhwmult=f5series --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-F5 %s
-// MSP430-HWMult-F5: "--start-group" "-lmul_f5"
+// RUN:   | FileCheck -check-prefix=HWMult-F5 %s
+// HWMult-F5: "--start-group" "-lmul_f5"
 
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mhwmult=none --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-NONE %s
+// RUN:   | FileCheck -check-prefix=HWMult-NONE %s
 // RUN: %clang %s -### -no-canonical-prefixes -target msp430 -mhwmult=none -mmcu=msp430f4783 --sysroot="" 2>&1 \
-// RUN:   | FileCheck -check-prefix=MSP430-HWMult-NONE %s
-
-// MSP430-HWMult-NONE: "--start-group" "-lmul_none"
+// RUN:   | FileCheck -check-prefix=HWMult-NONE %s
+// HWMult-NONE: "--start-group" "-lmul_none"