1 //===--- ToolChain.cpp - Collections of tools for one platform ------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "clang/Driver/ToolChain.h"
11 #include "ToolChains/CommonArgs.h"
12 #include "ToolChains/Arch/ARM.h"
13 #include "ToolChains/Clang.h"
14 #include "clang/Basic/ObjCRuntime.h"
15 #include "clang/Basic/VirtualFileSystem.h"
16 #include "clang/Config/config.h"
17 #include "clang/Driver/Action.h"
18 #include "clang/Driver/Driver.h"
19 #include "clang/Driver/DriverDiagnostic.h"
20 #include "clang/Driver/Options.h"
21 #include "clang/Driver/SanitizerArgs.h"
22 #include "clang/Driver/XRayArgs.h"
23 #include "llvm/ADT/SmallString.h"
24 #include "llvm/Option/Arg.h"
25 #include "llvm/Option/ArgList.h"
26 #include "llvm/Option/Option.h"
27 #include "llvm/Support/ErrorHandling.h"
28 #include "llvm/Support/FileSystem.h"
29 #include "llvm/Support/Path.h"
30 #include "llvm/Support/TargetParser.h"
31 #include "llvm/Support/TargetRegistry.h"
32 
33 using namespace clang::driver;
34 using namespace clang::driver::tools;
35 using namespace clang;
36 using namespace llvm;
37 using namespace llvm::opt;
38 
39 static llvm::opt::Arg *GetRTTIArgument(const ArgList &Args) {
40   return Args.getLastArg(options::OPT_mkernel, options::OPT_fapple_kext,
41                          options::OPT_fno_rtti, options::OPT_frtti);
42 }
43 
44 static ToolChain::RTTIMode CalculateRTTIMode(const ArgList &Args,
45                                              const llvm::Triple &Triple,
46                                              const Arg *CachedRTTIArg) {
47   // Explicit rtti/no-rtti args
48   if (CachedRTTIArg) {
49     if (CachedRTTIArg->getOption().matches(options::OPT_frtti))
50       return ToolChain::RM_EnabledExplicitly;
51     else
52       return ToolChain::RM_DisabledExplicitly;
53   }
54 
55   // -frtti is default, except for the PS4 CPU.
56   if (!Triple.isPS4CPU())
57     return ToolChain::RM_EnabledImplicitly;
58 
59   // On the PS4, turning on c++ exceptions turns on rtti.
60   // We're assuming that, if we see -fexceptions, rtti gets turned on.
61   Arg *Exceptions = Args.getLastArgNoClaim(
62       options::OPT_fcxx_exceptions, options::OPT_fno_cxx_exceptions,
63       options::OPT_fexceptions, options::OPT_fno_exceptions);
64   if (Exceptions &&
65       (Exceptions->getOption().matches(options::OPT_fexceptions) ||
66        Exceptions->getOption().matches(options::OPT_fcxx_exceptions)))
67     return ToolChain::RM_EnabledImplicitly;
68 
69   return ToolChain::RM_DisabledImplicitly;
70 }
71 
72 ToolChain::ToolChain(const Driver &D, const llvm::Triple &T,
73                      const ArgList &Args)
74     : D(D), Triple(T), Args(Args), CachedRTTIArg(GetRTTIArgument(Args)),
75       CachedRTTIMode(CalculateRTTIMode(Args, Triple, CachedRTTIArg)),
76       EffectiveTriple() {
77   if (Arg *A = Args.getLastArg(options::OPT_mthread_model))
78     if (!isThreadModelSupported(A->getValue()))
79       D.Diag(diag::err_drv_invalid_thread_model_for_target)
80           << A->getValue() << A->getAsString(Args);
81 
82   std::string CandidateLibPath = getArchSpecificLibPath();
83   if (getVFS().exists(CandidateLibPath))
84     getFilePaths().push_back(CandidateLibPath);
85 }
86 
87 ToolChain::~ToolChain() {
88 }
89 
90 vfs::FileSystem &ToolChain::getVFS() const { return getDriver().getVFS(); }
91 
92 bool ToolChain::useIntegratedAs() const {
93   return Args.hasFlag(options::OPT_fintegrated_as,
94                       options::OPT_fno_integrated_as,
95                       IsIntegratedAssemblerDefault());
96 }
97 
98 const SanitizerArgs& ToolChain::getSanitizerArgs() const {
99   if (!SanitizerArguments.get())
100     SanitizerArguments.reset(new SanitizerArgs(*this, Args));
101   return *SanitizerArguments.get();
102 }
103 
104 const XRayArgs& ToolChain::getXRayArgs() const {
105   if (!XRayArguments.get())
106     XRayArguments.reset(new XRayArgs(*this, Args));
107   return *XRayArguments.get();
108 }
109 
110 namespace {
111 struct DriverSuffix {
112   const char *Suffix;
113   const char *ModeFlag;
114 };
115 
116 const DriverSuffix *FindDriverSuffix(StringRef ProgName, size_t &Pos) {
117   // A list of known driver suffixes. Suffixes are compared against the
118   // program name in order. If there is a match, the frontend type is updated as
119   // necessary by applying the ModeFlag.
120   static const DriverSuffix DriverSuffixes[] = {
121       {"clang", nullptr},
122       {"clang++", "--driver-mode=g++"},
123       {"clang-c++", "--driver-mode=g++"},
124       {"clang-cc", nullptr},
125       {"clang-cpp", "--driver-mode=cpp"},
126       {"clang-g++", "--driver-mode=g++"},
127       {"clang-gcc", nullptr},
128       {"clang-cl", "--driver-mode=cl"},
129       {"cc", nullptr},
130       {"cpp", "--driver-mode=cpp"},
131       {"cl", "--driver-mode=cl"},
132       {"++", "--driver-mode=g++"},
133   };
134 
135   for (size_t i = 0; i < llvm::array_lengthof(DriverSuffixes); ++i) {
136     StringRef Suffix(DriverSuffixes[i].Suffix);
137     if (ProgName.endswith(Suffix)) {
138       Pos = ProgName.size() - Suffix.size();
139       return &DriverSuffixes[i];
140     }
141   }
142   return nullptr;
143 }
144 
145 /// Normalize the program name from argv[0] by stripping the file extension if
146 /// present and lower-casing the string on Windows.
147 std::string normalizeProgramName(llvm::StringRef Argv0) {
148   std::string ProgName = llvm::sys::path::stem(Argv0);
149 #ifdef LLVM_ON_WIN32
150   // Transform to lowercase for case insensitive file systems.
151   std::transform(ProgName.begin(), ProgName.end(), ProgName.begin(), ::tolower);
152 #endif
153   return ProgName;
154 }
155 
156 const DriverSuffix *parseDriverSuffix(StringRef ProgName, size_t &Pos) {
157   // Try to infer frontend type and default target from the program name by
158   // comparing it against DriverSuffixes in order.
159 
160   // If there is a match, the function tries to identify a target as prefix.
161   // E.g. "x86_64-linux-clang" as interpreted as suffix "clang" with target
162   // prefix "x86_64-linux". If such a target prefix is found, it may be
163   // added via -target as implicit first argument.
164   const DriverSuffix *DS = FindDriverSuffix(ProgName, Pos);
165 
166   if (!DS) {
167     // Try again after stripping any trailing version number:
168     // clang++3.5 -> clang++
169     ProgName = ProgName.rtrim("0123456789.");
170     DS = FindDriverSuffix(ProgName, Pos);
171   }
172 
173   if (!DS) {
174     // Try again after stripping trailing -component.
175     // clang++-tot -> clang++
176     ProgName = ProgName.slice(0, ProgName.rfind('-'));
177     DS = FindDriverSuffix(ProgName, Pos);
178   }
179   return DS;
180 }
181 } // anonymous namespace
182 
183 ParsedClangName
184 ToolChain::getTargetAndModeFromProgramName(StringRef PN) {
185   std::string ProgName = normalizeProgramName(PN);
186   size_t SuffixPos;
187   const DriverSuffix *DS = parseDriverSuffix(ProgName, SuffixPos);
188   if (!DS)
189     return ParsedClangName();
190   size_t SuffixEnd = SuffixPos + strlen(DS->Suffix);
191 
192   size_t LastComponent = ProgName.rfind('-', SuffixPos);
193   if (LastComponent == std::string::npos)
194     return ParsedClangName(ProgName.substr(0, SuffixEnd), DS->ModeFlag);
195   std::string ModeSuffix = ProgName.substr(LastComponent + 1,
196                                            SuffixEnd - LastComponent - 1);
197 
198   // Infer target from the prefix.
199   StringRef Prefix(ProgName);
200   Prefix = Prefix.slice(0, LastComponent);
201   std::string IgnoredError;
202   bool IsRegistered = llvm::TargetRegistry::lookupTarget(Prefix, IgnoredError);
203   return ParsedClangName{Prefix, ModeSuffix, DS->ModeFlag, IsRegistered};
204 }
205 
206 StringRef ToolChain::getDefaultUniversalArchName() const {
207   // In universal driver terms, the arch name accepted by -arch isn't exactly
208   // the same as the ones that appear in the triple. Roughly speaking, this is
209   // an inverse of the darwin::getArchTypeForDarwinArchName() function, but the
210   // only interesting special case is powerpc.
211   switch (Triple.getArch()) {
212   case llvm::Triple::ppc:
213     return "ppc";
214   case llvm::Triple::ppc64:
215     return "ppc64";
216   case llvm::Triple::ppc64le:
217     return "ppc64le";
218   default:
219     return Triple.getArchName();
220   }
221 }
222 
223 bool ToolChain::IsUnwindTablesDefault(const ArgList &Args) const {
224   return false;
225 }
226 
227 Tool *ToolChain::getClang() const {
228   if (!Clang)
229     Clang.reset(new tools::Clang(*this));
230   return Clang.get();
231 }
232 
233 Tool *ToolChain::buildAssembler() const {
234   return new tools::ClangAs(*this);
235 }
236 
237 Tool *ToolChain::buildLinker() const {
238   llvm_unreachable("Linking is not supported by this toolchain");
239 }
240 
241 Tool *ToolChain::getAssemble() const {
242   if (!Assemble)
243     Assemble.reset(buildAssembler());
244   return Assemble.get();
245 }
246 
247 Tool *ToolChain::getClangAs() const {
248   if (!Assemble)
249     Assemble.reset(new tools::ClangAs(*this));
250   return Assemble.get();
251 }
252 
253 Tool *ToolChain::getLink() const {
254   if (!Link)
255     Link.reset(buildLinker());
256   return Link.get();
257 }
258 
259 Tool *ToolChain::getOffloadBundler() const {
260   if (!OffloadBundler)
261     OffloadBundler.reset(new tools::OffloadBundler(*this));
262   return OffloadBundler.get();
263 }
264 
265 Tool *ToolChain::getTool(Action::ActionClass AC) const {
266   switch (AC) {
267   case Action::AssembleJobClass:
268     return getAssemble();
269 
270   case Action::LinkJobClass:
271     return getLink();
272 
273   case Action::InputClass:
274   case Action::BindArchClass:
275   case Action::OffloadClass:
276   case Action::LipoJobClass:
277   case Action::DsymutilJobClass:
278   case Action::VerifyDebugInfoJobClass:
279     llvm_unreachable("Invalid tool kind.");
280 
281   case Action::CompileJobClass:
282   case Action::PrecompileJobClass:
283   case Action::PreprocessJobClass:
284   case Action::AnalyzeJobClass:
285   case Action::MigrateJobClass:
286   case Action::VerifyPCHJobClass:
287   case Action::BackendJobClass:
288     return getClang();
289 
290   case Action::OffloadBundlingJobClass:
291   case Action::OffloadUnbundlingJobClass:
292     return getOffloadBundler();
293   }
294 
295   llvm_unreachable("Invalid tool kind.");
296 }
297 
298 static StringRef getArchNameForCompilerRTLib(const ToolChain &TC,
299                                              const ArgList &Args) {
300   const llvm::Triple &Triple = TC.getTriple();
301   bool IsWindows = Triple.isOSWindows();
302 
303   if (TC.getArch() == llvm::Triple::arm || TC.getArch() == llvm::Triple::armeb)
304     return (arm::getARMFloatABI(TC, Args) == arm::FloatABI::Hard && !IsWindows)
305                ? "armhf"
306                : "arm";
307 
308   // For historic reasons, Android library is using i686 instead of i386.
309   if (TC.getArch() == llvm::Triple::x86 && Triple.isAndroid())
310     return "i686";
311 
312   return llvm::Triple::getArchTypeName(TC.getArch());
313 }
314 
315 std::string ToolChain::getCompilerRTPath() const {
316   SmallString<128> Path(getDriver().ResourceDir);
317   StringRef OSLibName = Triple.isOSFreeBSD() ? "freebsd" : getOS();
318   llvm::sys::path::append(Path, "lib", OSLibName);
319   return Path.str();
320 }
321 
322 std::string ToolChain::getCompilerRT(const ArgList &Args, StringRef Component,
323                                      bool Shared) const {
324   const llvm::Triple &TT = getTriple();
325   const char *Env = TT.isAndroid() ? "-android" : "";
326   bool IsITANMSVCWindows =
327       TT.isWindowsMSVCEnvironment() || TT.isWindowsItaniumEnvironment();
328 
329   StringRef Arch = getArchNameForCompilerRTLib(*this, Args);
330   const char *Prefix = IsITANMSVCWindows ? "" : "lib";
331   const char *Suffix = Shared ? (Triple.isOSWindows() ? ".dll" : ".so")
332                               : (IsITANMSVCWindows ? ".lib" : ".a");
333 
334   SmallString<128> Path(getCompilerRTPath());
335   llvm::sys::path::append(Path, Prefix + Twine("clang_rt.") + Component + "-" +
336                                     Arch + Env + Suffix);
337   return Path.str();
338 }
339 
340 const char *ToolChain::getCompilerRTArgString(const llvm::opt::ArgList &Args,
341                                               StringRef Component,
342                                               bool Shared) const {
343   return Args.MakeArgString(getCompilerRT(Args, Component, Shared));
344 }
345 
346 std::string ToolChain::getArchSpecificLibPath() const {
347   SmallString<128> Path(getDriver().ResourceDir);
348   StringRef OSLibName = getTriple().isOSFreeBSD() ? "freebsd" : getOS();
349   llvm::sys::path::append(Path, "lib", OSLibName,
350                           llvm::Triple::getArchTypeName(getArch()));
351   return Path.str();
352 }
353 
354 bool ToolChain::needsProfileRT(const ArgList &Args) {
355   if (Args.hasFlag(options::OPT_fprofile_arcs, options::OPT_fno_profile_arcs,
356                    false) ||
357       Args.hasArg(options::OPT_fprofile_generate) ||
358       Args.hasArg(options::OPT_fprofile_generate_EQ) ||
359       Args.hasArg(options::OPT_fprofile_instr_generate) ||
360       Args.hasArg(options::OPT_fprofile_instr_generate_EQ) ||
361       Args.hasArg(options::OPT_fcreate_profile) ||
362       Args.hasArg(options::OPT_coverage))
363     return true;
364 
365   return false;
366 }
367 
368 Tool *ToolChain::SelectTool(const JobAction &JA) const {
369   if (getDriver().ShouldUseClangCompiler(JA)) return getClang();
370   Action::ActionClass AC = JA.getKind();
371   if (AC == Action::AssembleJobClass && useIntegratedAs())
372     return getClangAs();
373   return getTool(AC);
374 }
375 
376 std::string ToolChain::GetFilePath(const char *Name) const {
377   return D.GetFilePath(Name, *this);
378 }
379 
380 std::string ToolChain::GetProgramPath(const char *Name) const {
381   return D.GetProgramPath(Name, *this);
382 }
383 
384 std::string ToolChain::GetLinkerPath() const {
385   const Arg* A = Args.getLastArg(options::OPT_fuse_ld_EQ);
386   StringRef UseLinker = A ? A->getValue() : CLANG_DEFAULT_LINKER;
387 
388   if (llvm::sys::path::is_absolute(UseLinker)) {
389     // If we're passed what looks like an absolute path, don't attempt to
390     // second-guess that.
391     if (llvm::sys::fs::exists(UseLinker))
392       return UseLinker;
393   } else if (UseLinker.empty() || UseLinker == "ld") {
394     // If we're passed -fuse-ld= with no argument, or with the argument ld,
395     // then use whatever the default system linker is.
396     return GetProgramPath(getDefaultLinker());
397   } else {
398     llvm::SmallString<8> LinkerName("ld.");
399     LinkerName.append(UseLinker);
400 
401     std::string LinkerPath(GetProgramPath(LinkerName.c_str()));
402     if (llvm::sys::fs::exists(LinkerPath))
403       return LinkerPath;
404   }
405 
406   if (A)
407     getDriver().Diag(diag::err_drv_invalid_linker_name) << A->getAsString(Args);
408 
409   return GetProgramPath(getDefaultLinker());
410 }
411 
412 types::ID ToolChain::LookupTypeForExtension(StringRef Ext) const {
413   return types::lookupTypeForExtension(Ext);
414 }
415 
416 bool ToolChain::HasNativeLLVMSupport() const {
417   return false;
418 }
419 
420 bool ToolChain::isCrossCompiling() const {
421   llvm::Triple HostTriple(LLVM_HOST_TRIPLE);
422   switch (HostTriple.getArch()) {
423   // The A32/T32/T16 instruction sets are not separate architectures in this
424   // context.
425   case llvm::Triple::arm:
426   case llvm::Triple::armeb:
427   case llvm::Triple::thumb:
428   case llvm::Triple::thumbeb:
429     return getArch() != llvm::Triple::arm && getArch() != llvm::Triple::thumb &&
430            getArch() != llvm::Triple::armeb && getArch() != llvm::Triple::thumbeb;
431   default:
432     return HostTriple.getArch() != getArch();
433   }
434 }
435 
436 ObjCRuntime ToolChain::getDefaultObjCRuntime(bool isNonFragile) const {
437   return ObjCRuntime(isNonFragile ? ObjCRuntime::GNUstep : ObjCRuntime::GCC,
438                      VersionTuple());
439 }
440 
441 bool ToolChain::isThreadModelSupported(const StringRef Model) const {
442   if (Model == "single") {
443     // FIXME: 'single' is only supported on ARM and WebAssembly so far.
444     return Triple.getArch() == llvm::Triple::arm ||
445            Triple.getArch() == llvm::Triple::armeb ||
446            Triple.getArch() == llvm::Triple::thumb ||
447            Triple.getArch() == llvm::Triple::thumbeb ||
448            Triple.getArch() == llvm::Triple::wasm32 ||
449            Triple.getArch() == llvm::Triple::wasm64;
450   } else if (Model == "posix")
451     return true;
452 
453   return false;
454 }
455 
456 std::string ToolChain::ComputeLLVMTriple(const ArgList &Args,
457                                          types::ID InputType) const {
458   switch (getTriple().getArch()) {
459   default:
460     return getTripleString();
461 
462   case llvm::Triple::x86_64: {
463     llvm::Triple Triple = getTriple();
464     if (!Triple.isOSBinFormatMachO())
465       return getTripleString();
466 
467     if (Arg *A = Args.getLastArg(options::OPT_march_EQ)) {
468       // x86_64h goes in the triple. Other -march options just use the
469       // vanilla triple we already have.
470       StringRef MArch = A->getValue();
471       if (MArch == "x86_64h")
472         Triple.setArchName(MArch);
473     }
474     return Triple.getTriple();
475   }
476   case llvm::Triple::aarch64: {
477     llvm::Triple Triple = getTriple();
478     if (!Triple.isOSBinFormatMachO())
479       return getTripleString();
480 
481     // FIXME: older versions of ld64 expect the "arm64" component in the actual
482     // triple string and query it to determine whether an LTO file can be
483     // handled. Remove this when we don't care any more.
484     Triple.setArchName("arm64");
485     return Triple.getTriple();
486   }
487   case llvm::Triple::arm:
488   case llvm::Triple::armeb:
489   case llvm::Triple::thumb:
490   case llvm::Triple::thumbeb: {
491     // FIXME: Factor into subclasses.
492     llvm::Triple Triple = getTriple();
493     bool IsBigEndian = getTriple().getArch() == llvm::Triple::armeb ||
494                        getTriple().getArch() == llvm::Triple::thumbeb;
495 
496     // Handle pseudo-target flags '-mlittle-endian'/'-EL' and
497     // '-mbig-endian'/'-EB'.
498     if (Arg *A = Args.getLastArg(options::OPT_mlittle_endian,
499                                  options::OPT_mbig_endian)) {
500       IsBigEndian = !A->getOption().matches(options::OPT_mlittle_endian);
501     }
502 
503     // Thumb2 is the default for V7 on Darwin.
504     //
505     // FIXME: Thumb should just be another -target-feaure, not in the triple.
506     StringRef MCPU, MArch;
507     if (const Arg *A = Args.getLastArg(options::OPT_mcpu_EQ))
508       MCPU = A->getValue();
509     if (const Arg *A = Args.getLastArg(options::OPT_march_EQ))
510       MArch = A->getValue();
511     std::string CPU =
512         Triple.isOSBinFormatMachO()
513             ? tools::arm::getARMCPUForMArch(MArch, Triple).str()
514             : tools::arm::getARMTargetCPU(MCPU, MArch, Triple);
515     StringRef Suffix =
516       tools::arm::getLLVMArchSuffixForARM(CPU, MArch, Triple);
517     bool IsMProfile = ARM::parseArchProfile(Suffix) == ARM::ProfileKind::M;
518     bool ThumbDefault = IsMProfile || (ARM::parseArchVersion(Suffix) == 7 &&
519                                        getTriple().isOSBinFormatMachO());
520     // FIXME: this is invalid for WindowsCE
521     if (getTriple().isOSWindows())
522       ThumbDefault = true;
523     std::string ArchName;
524     if (IsBigEndian)
525       ArchName = "armeb";
526     else
527       ArchName = "arm";
528 
529     // Check if ARM ISA was explicitly selected (using -mno-thumb or -marm) for
530     // M-Class CPUs/architecture variants, which is not supported.
531     bool ARMModeRequested = !Args.hasFlag(options::OPT_mthumb,
532                                           options::OPT_mno_thumb, ThumbDefault);
533     if (IsMProfile && ARMModeRequested) {
534       if (!MCPU.empty())
535         getDriver().Diag(diag::err_cpu_unsupported_isa) << CPU << "ARM";
536        else
537         getDriver().Diag(diag::err_arch_unsupported_isa)
538           << tools::arm::getARMArch(MArch, getTriple()) << "ARM";
539     }
540 
541     // Assembly files should start in ARM mode, unless arch is M-profile.
542     // Windows is always thumb.
543     if ((InputType != types::TY_PP_Asm && Args.hasFlag(options::OPT_mthumb,
544          options::OPT_mno_thumb, ThumbDefault)) || IsMProfile ||
545          getTriple().isOSWindows()) {
546       if (IsBigEndian)
547         ArchName = "thumbeb";
548       else
549         ArchName = "thumb";
550     }
551     Triple.setArchName(ArchName + Suffix.str());
552 
553     return Triple.getTriple();
554   }
555   }
556 }
557 
558 std::string ToolChain::ComputeEffectiveClangTriple(const ArgList &Args,
559                                                    types::ID InputType) const {
560   return ComputeLLVMTriple(Args, InputType);
561 }
562 
563 void ToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
564                                           ArgStringList &CC1Args) const {
565   // Each toolchain should provide the appropriate include flags.
566 }
567 
568 void ToolChain::addClangTargetOptions(
569     const ArgList &DriverArgs, ArgStringList &CC1Args,
570     Action::OffloadKind DeviceOffloadKind) const {}
571 
572 void ToolChain::addClangWarningOptions(ArgStringList &CC1Args) const {}
573 
574 void ToolChain::addProfileRTLibs(const llvm::opt::ArgList &Args,
575                                  llvm::opt::ArgStringList &CmdArgs) const {
576   if (!needsProfileRT(Args)) return;
577 
578   CmdArgs.push_back(getCompilerRTArgString(Args, "profile"));
579 }
580 
581 ToolChain::RuntimeLibType ToolChain::GetRuntimeLibType(
582     const ArgList &Args) const {
583   const Arg* A = Args.getLastArg(options::OPT_rtlib_EQ);
584   StringRef LibName = A ? A->getValue() : CLANG_DEFAULT_RTLIB;
585 
586   // Only use "platform" in tests to override CLANG_DEFAULT_RTLIB!
587   if (LibName == "compiler-rt")
588     return ToolChain::RLT_CompilerRT;
589   else if (LibName == "libgcc")
590     return ToolChain::RLT_Libgcc;
591   else if (LibName == "platform")
592     return GetDefaultRuntimeLibType();
593 
594   if (A)
595     getDriver().Diag(diag::err_drv_invalid_rtlib_name) << A->getAsString(Args);
596 
597   return GetDefaultRuntimeLibType();
598 }
599 
600 ToolChain::CXXStdlibType ToolChain::GetCXXStdlibType(const ArgList &Args) const{
601   const Arg *A = Args.getLastArg(options::OPT_stdlib_EQ);
602   StringRef LibName = A ? A->getValue() : CLANG_DEFAULT_CXX_STDLIB;
603 
604   // Only use "platform" in tests to override CLANG_DEFAULT_CXX_STDLIB!
605   if (LibName == "libc++")
606     return ToolChain::CST_Libcxx;
607   else if (LibName == "libstdc++")
608     return ToolChain::CST_Libstdcxx;
609   else if (LibName == "platform")
610     return GetDefaultCXXStdlibType();
611 
612   if (A)
613     getDriver().Diag(diag::err_drv_invalid_stdlib_name) << A->getAsString(Args);
614 
615   return GetDefaultCXXStdlibType();
616 }
617 
618 /// \brief Utility function to add a system include directory to CC1 arguments.
619 /*static*/ void ToolChain::addSystemInclude(const ArgList &DriverArgs,
620                                             ArgStringList &CC1Args,
621                                             const Twine &Path) {
622   CC1Args.push_back("-internal-isystem");
623   CC1Args.push_back(DriverArgs.MakeArgString(Path));
624 }
625 
626 /// \brief Utility function to add a system include directory with extern "C"
627 /// semantics to CC1 arguments.
628 ///
629 /// Note that this should be used rarely, and only for directories that
630 /// historically and for legacy reasons are treated as having implicit extern
631 /// "C" semantics. These semantics are *ignored* by and large today, but its
632 /// important to preserve the preprocessor changes resulting from the
633 /// classification.
634 /*static*/ void ToolChain::addExternCSystemInclude(const ArgList &DriverArgs,
635                                                    ArgStringList &CC1Args,
636                                                    const Twine &Path) {
637   CC1Args.push_back("-internal-externc-isystem");
638   CC1Args.push_back(DriverArgs.MakeArgString(Path));
639 }
640 
641 void ToolChain::addExternCSystemIncludeIfExists(const ArgList &DriverArgs,
642                                                 ArgStringList &CC1Args,
643                                                 const Twine &Path) {
644   if (llvm::sys::fs::exists(Path))
645     addExternCSystemInclude(DriverArgs, CC1Args, Path);
646 }
647 
648 /// \brief Utility function to add a list of system include directories to CC1.
649 /*static*/ void ToolChain::addSystemIncludes(const ArgList &DriverArgs,
650                                              ArgStringList &CC1Args,
651                                              ArrayRef<StringRef> Paths) {
652   for (StringRef Path : Paths) {
653     CC1Args.push_back("-internal-isystem");
654     CC1Args.push_back(DriverArgs.MakeArgString(Path));
655   }
656 }
657 
658 void ToolChain::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
659                                              ArgStringList &CC1Args) const {
660   // Header search paths should be handled by each of the subclasses.
661   // Historically, they have not been, and instead have been handled inside of
662   // the CC1-layer frontend. As the logic is hoisted out, this generic function
663   // will slowly stop being called.
664   //
665   // While it is being called, replicate a bit of a hack to propagate the
666   // '-stdlib=' flag down to CC1 so that it can in turn customize the C++
667   // header search paths with it. Once all systems are overriding this
668   // function, the CC1 flag and this line can be removed.
669   DriverArgs.AddAllArgs(CC1Args, options::OPT_stdlib_EQ);
670 }
671 
672 bool ToolChain::ShouldLinkCXXStdlib(const llvm::opt::ArgList &Args) const {
673   return getDriver().CCCIsCXX() &&
674          !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs,
675                       options::OPT_nostdlibxx);
676 }
677 
678 void ToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
679                                     ArgStringList &CmdArgs) const {
680   assert(!Args.hasArg(options::OPT_nostdlibxx) &&
681          "should not have called this");
682   CXXStdlibType Type = GetCXXStdlibType(Args);
683 
684   switch (Type) {
685   case ToolChain::CST_Libcxx:
686     CmdArgs.push_back("-lc++");
687     break;
688 
689   case ToolChain::CST_Libstdcxx:
690     CmdArgs.push_back("-lstdc++");
691     break;
692   }
693 }
694 
695 void ToolChain::AddFilePathLibArgs(const ArgList &Args,
696                                    ArgStringList &CmdArgs) const {
697   for (const auto &LibPath : getFilePaths())
698     if(LibPath.length() > 0)
699       CmdArgs.push_back(Args.MakeArgString(StringRef("-L") + LibPath));
700 }
701 
702 void ToolChain::AddCCKextLibArgs(const ArgList &Args,
703                                  ArgStringList &CmdArgs) const {
704   CmdArgs.push_back("-lcc_kext");
705 }
706 
707 bool ToolChain::AddFastMathRuntimeIfAvailable(const ArgList &Args,
708                                               ArgStringList &CmdArgs) const {
709   // Do not check for -fno-fast-math or -fno-unsafe-math when -Ofast passed
710   // (to keep the linker options consistent with gcc and clang itself).
711   if (!isOptimizationLevelFast(Args)) {
712     // Check if -ffast-math or -funsafe-math.
713     Arg *A =
714         Args.getLastArg(options::OPT_ffast_math, options::OPT_fno_fast_math,
715                         options::OPT_funsafe_math_optimizations,
716                         options::OPT_fno_unsafe_math_optimizations);
717 
718     if (!A || A->getOption().getID() == options::OPT_fno_fast_math ||
719         A->getOption().getID() == options::OPT_fno_unsafe_math_optimizations)
720       return false;
721   }
722   // If crtfastmath.o exists add it to the arguments.
723   std::string Path = GetFilePath("crtfastmath.o");
724   if (Path == "crtfastmath.o") // Not found.
725     return false;
726 
727   CmdArgs.push_back(Args.MakeArgString(Path));
728   return true;
729 }
730 
731 SanitizerMask ToolChain::getSupportedSanitizers() const {
732   // Return sanitizers which don't require runtime support and are not
733   // platform dependent.
734   using namespace SanitizerKind;
735   SanitizerMask Res = (Undefined & ~Vptr & ~Function) | (CFI & ~CFIICall) |
736                       CFICastStrict | UnsignedIntegerOverflow | Nullability |
737                       LocalBounds;
738   if (getTriple().getArch() == llvm::Triple::x86 ||
739       getTriple().getArch() == llvm::Triple::x86_64 ||
740       getTriple().getArch() == llvm::Triple::arm ||
741       getTriple().getArch() == llvm::Triple::aarch64 ||
742       getTriple().getArch() == llvm::Triple::wasm32 ||
743       getTriple().getArch() == llvm::Triple::wasm64)
744     Res |= CFIICall;
745   return Res;
746 }
747 
748 void ToolChain::AddCudaIncludeArgs(const ArgList &DriverArgs,
749                                    ArgStringList &CC1Args) const {}
750 
751 void ToolChain::AddIAMCUIncludeArgs(const ArgList &DriverArgs,
752                                     ArgStringList &CC1Args) const {}
753 
754 static VersionTuple separateMSVCFullVersion(unsigned Version) {
755   if (Version < 100)
756     return VersionTuple(Version);
757 
758   if (Version < 10000)
759     return VersionTuple(Version / 100, Version % 100);
760 
761   unsigned Build = 0, Factor = 1;
762   for (; Version > 10000; Version = Version / 10, Factor = Factor * 10)
763     Build = Build + (Version % 10) * Factor;
764   return VersionTuple(Version / 100, Version % 100, Build);
765 }
766 
767 VersionTuple
768 ToolChain::computeMSVCVersion(const Driver *D,
769                               const llvm::opt::ArgList &Args) const {
770   const Arg *MSCVersion = Args.getLastArg(options::OPT_fmsc_version);
771   const Arg *MSCompatibilityVersion =
772       Args.getLastArg(options::OPT_fms_compatibility_version);
773 
774   if (MSCVersion && MSCompatibilityVersion) {
775     if (D)
776       D->Diag(diag::err_drv_argument_not_allowed_with)
777           << MSCVersion->getAsString(Args)
778           << MSCompatibilityVersion->getAsString(Args);
779     return VersionTuple();
780   }
781 
782   if (MSCompatibilityVersion) {
783     VersionTuple MSVT;
784     if (MSVT.tryParse(MSCompatibilityVersion->getValue())) {
785       if (D)
786         D->Diag(diag::err_drv_invalid_value)
787             << MSCompatibilityVersion->getAsString(Args)
788             << MSCompatibilityVersion->getValue();
789     } else {
790       return MSVT;
791     }
792   }
793 
794   if (MSCVersion) {
795     unsigned Version = 0;
796     if (StringRef(MSCVersion->getValue()).getAsInteger(10, Version)) {
797       if (D)
798         D->Diag(diag::err_drv_invalid_value)
799             << MSCVersion->getAsString(Args) << MSCVersion->getValue();
800     } else {
801       return separateMSVCFullVersion(Version);
802     }
803   }
804 
805   return VersionTuple();
806 }
807 
808 llvm::opt::DerivedArgList *
809 ToolChain::TranslateOpenMPTargetArgs(const llvm::opt::DerivedArgList &Args,
810     Action::OffloadKind DeviceOffloadKind) const {
811   if (DeviceOffloadKind == Action::OFK_OpenMP) {
812     DerivedArgList *DAL = new DerivedArgList(Args.getBaseArgs());
813     const OptTable &Opts = getDriver().getOpts();
814     bool NewArgAdded = false;
815 
816     // Handle -Xopenmp-target flags
817     for (Arg *A : Args) {
818       // Exclude flags which may only apply to the host toolchain.
819       // Do not exclude flags when the host triple (AuxTriple),
820       // matches the current toolchain triple.
821       if (A->getOption().matches(options::OPT_m_Group)) {
822         if (getAuxTriple() && getAuxTriple()->str() == getTriple().str())
823           DAL->append(A);
824         continue;
825       }
826 
827       unsigned Index;
828       unsigned Prev;
829       bool XOpenMPTargetNoTriple = A->getOption().matches(
830           options::OPT_Xopenmp_target);
831 
832       if (A->getOption().matches(options::OPT_Xopenmp_target_EQ)) {
833         // Passing device args: -Xopenmp-target=<triple> -opt=val.
834         if (A->getValue(0) == getTripleString())
835           Index = Args.getBaseArgs().MakeIndex(A->getValue(1));
836         else
837           continue;
838       } else if (XOpenMPTargetNoTriple) {
839         // Passing device args: -Xopenmp-target -opt=val.
840         Index = Args.getBaseArgs().MakeIndex(A->getValue(0));
841       } else {
842         DAL->append(A);
843         continue;
844       }
845 
846       // Parse the argument to -Xopenmp-target.
847       Prev = Index;
848       std::unique_ptr<Arg> XOpenMPTargetArg(Opts.ParseOneArg(Args, Index));
849       if (!XOpenMPTargetArg || Index > Prev + 1) {
850         getDriver().Diag(diag::err_drv_invalid_Xopenmp_target_with_args)
851             << A->getAsString(Args);
852         continue;
853       }
854       if (XOpenMPTargetNoTriple && XOpenMPTargetArg &&
855           Args.getAllArgValues(
856               options::OPT_fopenmp_targets_EQ).size() != 1) {
857         getDriver().Diag(diag::err_drv_Xopenmp_target_missing_triple);
858         continue;
859       }
860       XOpenMPTargetArg->setBaseArg(A);
861       A = XOpenMPTargetArg.release();
862       DAL->append(A);
863       NewArgAdded = true;
864     }
865 
866     if (NewArgAdded) {
867       return DAL;
868     } else {
869       delete DAL;
870     }
871   }
872 
873   return nullptr;
874 }
875