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