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