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 "InputInfo.h"
12 #include "ToolChains/Arch/ARM.h"
13 #include "ToolChains/Clang.h"
14 #include "clang/Basic/ObjCRuntime.h"
15 #include "clang/Basic/Sanitizers.h"
16 #include "clang/Basic/VirtualFileSystem.h"
17 #include "clang/Config/config.h"
18 #include "clang/Driver/Action.h"
19 #include "clang/Driver/Driver.h"
20 #include "clang/Driver/DriverDiagnostic.h"
21 #include "clang/Driver/Job.h"
22 #include "clang/Driver/Options.h"
23 #include "clang/Driver/SanitizerArgs.h"
24 #include "clang/Driver/XRayArgs.h"
25 #include "llvm/ADT/STLExtras.h"
26 #include "llvm/ADT/SmallString.h"
27 #include "llvm/ADT/StringRef.h"
28 #include "llvm/ADT/Triple.h"
29 #include "llvm/ADT/Twine.h"
30 #include "llvm/Config/llvm-config.h"
31 #include "llvm/MC/MCTargetOptions.h"
32 #include "llvm/Option/Arg.h"
33 #include "llvm/Option/ArgList.h"
34 #include "llvm/Option/OptTable.h"
35 #include "llvm/Option/Option.h"
36 #include "llvm/Support/ErrorHandling.h"
37 #include "llvm/Support/FileSystem.h"
38 #include "llvm/Support/Path.h"
39 #include "llvm/Support/TargetParser.h"
40 #include "llvm/Support/TargetRegistry.h"
41 #include "llvm/Support/VersionTuple.h"
42 #include <cassert>
43 #include <cstddef>
44 #include <cstring>
45 #include <string>
46 
47 using namespace clang;
48 using namespace driver;
49 using namespace tools;
50 using namespace llvm;
51 using namespace llvm::opt;
52 
53 static llvm::opt::Arg *GetRTTIArgument(const ArgList &Args) {
54   return Args.getLastArg(options::OPT_mkernel, options::OPT_fapple_kext,
55                          options::OPT_fno_rtti, options::OPT_frtti);
56 }
57 
58 static ToolChain::RTTIMode CalculateRTTIMode(const ArgList &Args,
59                                              const llvm::Triple &Triple,
60                                              const Arg *CachedRTTIArg) {
61   // Explicit rtti/no-rtti args
62   if (CachedRTTIArg) {
63     if (CachedRTTIArg->getOption().matches(options::OPT_frtti))
64       return ToolChain::RM_Enabled;
65     else
66       return ToolChain::RM_Disabled;
67   }
68 
69   // -frtti is default, except for the PS4 CPU.
70   return (Triple.isPS4CPU()) ? ToolChain::RM_Disabled : ToolChain::RM_Enabled;
71 }
72 
73 ToolChain::ToolChain(const Driver &D, const llvm::Triple &T,
74                      const ArgList &Args)
75     : D(D), Triple(T), Args(Args), CachedRTTIArg(GetRTTIArgument(Args)),
76       CachedRTTIMode(CalculateRTTIMode(Args, Triple, CachedRTTIArg)) {
77   SmallString<128> P;
78 
79   P.assign(D.ResourceDir);
80   llvm::sys::path::append(P, D.getTargetTriple(), "lib");
81   if (getVFS().exists(P))
82     getLibraryPaths().push_back(P.str());
83 
84   P.assign(D.ResourceDir);
85   llvm::sys::path::append(P, Triple.str(), "lib");
86   if (getVFS().exists(P))
87     getLibraryPaths().push_back(P.str());
88 
89   std::string CandidateLibPath = getArchSpecificLibPath();
90   if (getVFS().exists(CandidateLibPath))
91     getFilePaths().push_back(CandidateLibPath);
92 }
93 
94 void ToolChain::setTripleEnvironment(llvm::Triple::EnvironmentType Env) {
95   Triple.setEnvironment(Env);
96   if (EffectiveTriple != llvm::Triple())
97     EffectiveTriple.setEnvironment(Env);
98 }
99 
100 ToolChain::~ToolChain() = default;
101 
102 vfs::FileSystem &ToolChain::getVFS() const { return getDriver().getVFS(); }
103 
104 bool ToolChain::useIntegratedAs() const {
105   return Args.hasFlag(options::OPT_fintegrated_as,
106                       options::OPT_fno_integrated_as,
107                       IsIntegratedAssemblerDefault());
108 }
109 
110 bool ToolChain::useRelaxRelocations() const {
111   return ENABLE_X86_RELAX_RELOCATIONS;
112 }
113 
114 const SanitizerArgs& ToolChain::getSanitizerArgs() const {
115   if (!SanitizerArguments.get())
116     SanitizerArguments.reset(new SanitizerArgs(*this, Args));
117   return *SanitizerArguments.get();
118 }
119 
120 const XRayArgs& ToolChain::getXRayArgs() const {
121   if (!XRayArguments.get())
122     XRayArguments.reset(new XRayArgs(*this, Args));
123   return *XRayArguments.get();
124 }
125 
126 namespace {
127 
128 struct DriverSuffix {
129   const char *Suffix;
130   const char *ModeFlag;
131 };
132 
133 } // namespace
134 
135 static const DriverSuffix *FindDriverSuffix(StringRef ProgName, size_t &Pos) {
136   // A list of known driver suffixes. Suffixes are compared against the
137   // program name in order. If there is a match, the frontend type is updated as
138   // necessary by applying the ModeFlag.
139   static const DriverSuffix DriverSuffixes[] = {
140       {"clang", nullptr},
141       {"clang++", "--driver-mode=g++"},
142       {"clang-c++", "--driver-mode=g++"},
143       {"clang-cc", nullptr},
144       {"clang-cpp", "--driver-mode=cpp"},
145       {"clang-g++", "--driver-mode=g++"},
146       {"clang-gcc", nullptr},
147       {"clang-cl", "--driver-mode=cl"},
148       {"cc", nullptr},
149       {"cpp", "--driver-mode=cpp"},
150       {"cl", "--driver-mode=cl"},
151       {"++", "--driver-mode=g++"},
152   };
153 
154   for (size_t i = 0; i < llvm::array_lengthof(DriverSuffixes); ++i) {
155     StringRef Suffix(DriverSuffixes[i].Suffix);
156     if (ProgName.endswith(Suffix)) {
157       Pos = ProgName.size() - Suffix.size();
158       return &DriverSuffixes[i];
159     }
160   }
161   return nullptr;
162 }
163 
164 /// Normalize the program name from argv[0] by stripping the file extension if
165 /// present and lower-casing the string on Windows.
166 static std::string normalizeProgramName(llvm::StringRef Argv0) {
167   std::string ProgName = llvm::sys::path::stem(Argv0);
168 #ifdef _WIN32
169   // Transform to lowercase for case insensitive file systems.
170   std::transform(ProgName.begin(), ProgName.end(), ProgName.begin(), ::tolower);
171 #endif
172   return ProgName;
173 }
174 
175 static const DriverSuffix *parseDriverSuffix(StringRef ProgName, size_t &Pos) {
176   // Try to infer frontend type and default target from the program name by
177   // comparing it against DriverSuffixes in order.
178 
179   // If there is a match, the function tries to identify a target as prefix.
180   // E.g. "x86_64-linux-clang" as interpreted as suffix "clang" with target
181   // prefix "x86_64-linux". If such a target prefix is found, it may be
182   // added via -target as implicit first argument.
183   const DriverSuffix *DS = FindDriverSuffix(ProgName, Pos);
184 
185   if (!DS) {
186     // Try again after stripping any trailing version number:
187     // clang++3.5 -> clang++
188     ProgName = ProgName.rtrim("0123456789.");
189     DS = FindDriverSuffix(ProgName, Pos);
190   }
191 
192   if (!DS) {
193     // Try again after stripping trailing -component.
194     // clang++-tot -> clang++
195     ProgName = ProgName.slice(0, ProgName.rfind('-'));
196     DS = FindDriverSuffix(ProgName, Pos);
197   }
198   return DS;
199 }
200 
201 ParsedClangName
202 ToolChain::getTargetAndModeFromProgramName(StringRef PN) {
203   std::string ProgName = normalizeProgramName(PN);
204   size_t SuffixPos;
205   const DriverSuffix *DS = parseDriverSuffix(ProgName, SuffixPos);
206   if (!DS)
207     return {};
208   size_t SuffixEnd = SuffixPos + strlen(DS->Suffix);
209 
210   size_t LastComponent = ProgName.rfind('-', SuffixPos);
211   if (LastComponent == std::string::npos)
212     return ParsedClangName(ProgName.substr(0, SuffixEnd), DS->ModeFlag);
213   std::string ModeSuffix = ProgName.substr(LastComponent + 1,
214                                            SuffixEnd - LastComponent - 1);
215 
216   // Infer target from the prefix.
217   StringRef Prefix(ProgName);
218   Prefix = Prefix.slice(0, LastComponent);
219   std::string IgnoredError;
220   bool IsRegistered = llvm::TargetRegistry::lookupTarget(Prefix, IgnoredError);
221   return ParsedClangName{Prefix, ModeSuffix, DS->ModeFlag, IsRegistered};
222 }
223 
224 StringRef ToolChain::getDefaultUniversalArchName() const {
225   // In universal driver terms, the arch name accepted by -arch isn't exactly
226   // the same as the ones that appear in the triple. Roughly speaking, this is
227   // an inverse of the darwin::getArchTypeForDarwinArchName() function, but the
228   // only interesting special case is powerpc.
229   switch (Triple.getArch()) {
230   case llvm::Triple::ppc:
231     return "ppc";
232   case llvm::Triple::ppc64:
233     return "ppc64";
234   case llvm::Triple::ppc64le:
235     return "ppc64le";
236   default:
237     return Triple.getArchName();
238   }
239 }
240 
241 std::string ToolChain::getInputFilename(const InputInfo &Input) const {
242   return Input.getFilename();
243 }
244 
245 bool ToolChain::IsUnwindTablesDefault(const ArgList &Args) const {
246   return false;
247 }
248 
249 Tool *ToolChain::getClang() const {
250   if (!Clang)
251     Clang.reset(new tools::Clang(*this));
252   return Clang.get();
253 }
254 
255 Tool *ToolChain::buildAssembler() const {
256   return new tools::ClangAs(*this);
257 }
258 
259 Tool *ToolChain::buildLinker() const {
260   llvm_unreachable("Linking is not supported by this toolchain");
261 }
262 
263 Tool *ToolChain::getAssemble() const {
264   if (!Assemble)
265     Assemble.reset(buildAssembler());
266   return Assemble.get();
267 }
268 
269 Tool *ToolChain::getClangAs() const {
270   if (!Assemble)
271     Assemble.reset(new tools::ClangAs(*this));
272   return Assemble.get();
273 }
274 
275 Tool *ToolChain::getLink() const {
276   if (!Link)
277     Link.reset(buildLinker());
278   return Link.get();
279 }
280 
281 Tool *ToolChain::getOffloadBundler() const {
282   if (!OffloadBundler)
283     OffloadBundler.reset(new tools::OffloadBundler(*this));
284   return OffloadBundler.get();
285 }
286 
287 Tool *ToolChain::getTool(Action::ActionClass AC) const {
288   switch (AC) {
289   case Action::AssembleJobClass:
290     return getAssemble();
291 
292   case Action::LinkJobClass:
293     return getLink();
294 
295   case Action::InputClass:
296   case Action::BindArchClass:
297   case Action::OffloadClass:
298   case Action::LipoJobClass:
299   case Action::DsymutilJobClass:
300   case Action::VerifyDebugInfoJobClass:
301     llvm_unreachable("Invalid tool kind.");
302 
303   case Action::CompileJobClass:
304   case Action::PrecompileJobClass:
305   case Action::PreprocessJobClass:
306   case Action::AnalyzeJobClass:
307   case Action::MigrateJobClass:
308   case Action::VerifyPCHJobClass:
309   case Action::BackendJobClass:
310     return getClang();
311 
312   case Action::OffloadBundlingJobClass:
313   case Action::OffloadUnbundlingJobClass:
314     return getOffloadBundler();
315   }
316 
317   llvm_unreachable("Invalid tool kind.");
318 }
319 
320 static StringRef getArchNameForCompilerRTLib(const ToolChain &TC,
321                                              const ArgList &Args) {
322   const llvm::Triple &Triple = TC.getTriple();
323   bool IsWindows = Triple.isOSWindows();
324 
325   if (TC.getArch() == llvm::Triple::arm || TC.getArch() == llvm::Triple::armeb)
326     return (arm::getARMFloatABI(TC, Args) == arm::FloatABI::Hard && !IsWindows)
327                ? "armhf"
328                : "arm";
329 
330   // For historic reasons, Android library is using i686 instead of i386.
331   if (TC.getArch() == llvm::Triple::x86 && Triple.isAndroid())
332     return "i686";
333 
334   return llvm::Triple::getArchTypeName(TC.getArch());
335 }
336 
337 StringRef ToolChain::getOSLibName() const {
338   switch (Triple.getOS()) {
339   case llvm::Triple::FreeBSD:
340     return "freebsd";
341   case llvm::Triple::NetBSD:
342     return "netbsd";
343   case llvm::Triple::OpenBSD:
344     return "openbsd";
345   case llvm::Triple::Solaris:
346     return "sunos";
347   default:
348     return getOS();
349   }
350 }
351 
352 std::string ToolChain::getCompilerRTPath() const {
353   SmallString<128> Path(getDriver().ResourceDir);
354   if (Triple.isOSUnknown()) {
355     llvm::sys::path::append(Path, "lib");
356   } else {
357     llvm::sys::path::append(Path, "lib", getOSLibName());
358   }
359   return Path.str();
360 }
361 
362 std::string ToolChain::getCompilerRT(const ArgList &Args, StringRef Component,
363                                      bool Shared) const {
364   const llvm::Triple &TT = getTriple();
365   bool IsITANMSVCWindows =
366       TT.isWindowsMSVCEnvironment() || TT.isWindowsItaniumEnvironment();
367 
368   const char *Prefix = IsITANMSVCWindows ? "" : "lib";
369   const char *Suffix = Shared ? (Triple.isOSWindows() ? ".dll" : ".so")
370                               : (IsITANMSVCWindows ? ".lib" : ".a");
371 
372   for (const auto &LibPath : getLibraryPaths()) {
373     SmallString<128> P(LibPath);
374     llvm::sys::path::append(P, Prefix + Twine("clang_rt.") + Component + Suffix);
375     if (getVFS().exists(P))
376       return P.str();
377   }
378 
379   StringRef Arch = getArchNameForCompilerRTLib(*this, Args);
380   const char *Env = TT.isAndroid() ? "-android" : "";
381   SmallString<128> Path(getCompilerRTPath());
382   llvm::sys::path::append(Path, Prefix + Twine("clang_rt.") + Component + "-" +
383                                     Arch + Env + Suffix);
384   return Path.str();
385 }
386 
387 const char *ToolChain::getCompilerRTArgString(const llvm::opt::ArgList &Args,
388                                               StringRef Component,
389                                               bool Shared) const {
390   return Args.MakeArgString(getCompilerRT(Args, Component, Shared));
391 }
392 
393 std::string ToolChain::getArchSpecificLibPath() const {
394   SmallString<128> Path(getDriver().ResourceDir);
395   llvm::sys::path::append(Path, "lib", getOSLibName(),
396                           llvm::Triple::getArchTypeName(getArch()));
397   return Path.str();
398 }
399 
400 bool ToolChain::needsProfileRT(const ArgList &Args) {
401   if (Args.hasFlag(options::OPT_fprofile_arcs, options::OPT_fno_profile_arcs,
402                    false) ||
403       Args.hasArg(options::OPT_fprofile_generate) ||
404       Args.hasArg(options::OPT_fprofile_generate_EQ) ||
405       Args.hasArg(options::OPT_fprofile_instr_generate) ||
406       Args.hasArg(options::OPT_fprofile_instr_generate_EQ) ||
407       Args.hasArg(options::OPT_fcreate_profile) ||
408       Args.hasArg(options::OPT_coverage))
409     return true;
410 
411   return false;
412 }
413 
414 Tool *ToolChain::SelectTool(const JobAction &JA) const {
415   if (getDriver().ShouldUseClangCompiler(JA)) return getClang();
416   Action::ActionClass AC = JA.getKind();
417   if (AC == Action::AssembleJobClass && useIntegratedAs())
418     return getClangAs();
419   return getTool(AC);
420 }
421 
422 std::string ToolChain::GetFilePath(const char *Name) const {
423   return D.GetFilePath(Name, *this);
424 }
425 
426 std::string ToolChain::GetProgramPath(const char *Name) const {
427   return D.GetProgramPath(Name, *this);
428 }
429 
430 std::string ToolChain::GetLinkerPath() const {
431   const Arg* A = Args.getLastArg(options::OPT_fuse_ld_EQ);
432   StringRef UseLinker = A ? A->getValue() : CLANG_DEFAULT_LINKER;
433 
434   if (llvm::sys::path::is_absolute(UseLinker)) {
435     // If we're passed what looks like an absolute path, don't attempt to
436     // second-guess that.
437     if (llvm::sys::fs::can_execute(UseLinker))
438       return UseLinker;
439   } else if (UseLinker.empty() || UseLinker == "ld") {
440     // If we're passed -fuse-ld= with no argument, or with the argument ld,
441     // then use whatever the default system linker is.
442     return GetProgramPath(getDefaultLinker());
443   } else {
444     llvm::SmallString<8> LinkerName;
445     if (Triple.isOSDarwin())
446       LinkerName.append("ld64.");
447     else
448       LinkerName.append("ld.");
449     LinkerName.append(UseLinker);
450 
451     std::string LinkerPath(GetProgramPath(LinkerName.c_str()));
452     if (llvm::sys::fs::can_execute(LinkerPath))
453       return LinkerPath;
454   }
455 
456   if (A)
457     getDriver().Diag(diag::err_drv_invalid_linker_name) << A->getAsString(Args);
458 
459   return GetProgramPath(getDefaultLinker());
460 }
461 
462 types::ID ToolChain::LookupTypeForExtension(StringRef Ext) const {
463   return types::lookupTypeForExtension(Ext);
464 }
465 
466 bool ToolChain::HasNativeLLVMSupport() const {
467   return false;
468 }
469 
470 bool ToolChain::isCrossCompiling() const {
471   llvm::Triple HostTriple(LLVM_HOST_TRIPLE);
472   switch (HostTriple.getArch()) {
473   // The A32/T32/T16 instruction sets are not separate architectures in this
474   // context.
475   case llvm::Triple::arm:
476   case llvm::Triple::armeb:
477   case llvm::Triple::thumb:
478   case llvm::Triple::thumbeb:
479     return getArch() != llvm::Triple::arm && getArch() != llvm::Triple::thumb &&
480            getArch() != llvm::Triple::armeb && getArch() != llvm::Triple::thumbeb;
481   default:
482     return HostTriple.getArch() != getArch();
483   }
484 }
485 
486 ObjCRuntime ToolChain::getDefaultObjCRuntime(bool isNonFragile) const {
487   return ObjCRuntime(isNonFragile ? ObjCRuntime::GNUstep : ObjCRuntime::GCC,
488                      VersionTuple());
489 }
490 
491 llvm::ExceptionHandling
492 ToolChain::GetExceptionModel(const llvm::opt::ArgList &Args) const {
493   return llvm::ExceptionHandling::None;
494 }
495 
496 bool ToolChain::isThreadModelSupported(const StringRef Model) const {
497   if (Model == "single") {
498     // FIXME: 'single' is only supported on ARM and WebAssembly so far.
499     return Triple.getArch() == llvm::Triple::arm ||
500            Triple.getArch() == llvm::Triple::armeb ||
501            Triple.getArch() == llvm::Triple::thumb ||
502            Triple.getArch() == llvm::Triple::thumbeb ||
503            Triple.getArch() == llvm::Triple::wasm32 ||
504            Triple.getArch() == llvm::Triple::wasm64;
505   } else if (Model == "posix")
506     return true;
507 
508   return false;
509 }
510 
511 std::string ToolChain::ComputeLLVMTriple(const ArgList &Args,
512                                          types::ID InputType) const {
513   switch (getTriple().getArch()) {
514   default:
515     return getTripleString();
516 
517   case llvm::Triple::x86_64: {
518     llvm::Triple Triple = getTriple();
519     if (!Triple.isOSBinFormatMachO())
520       return getTripleString();
521 
522     if (Arg *A = Args.getLastArg(options::OPT_march_EQ)) {
523       // x86_64h goes in the triple. Other -march options just use the
524       // vanilla triple we already have.
525       StringRef MArch = A->getValue();
526       if (MArch == "x86_64h")
527         Triple.setArchName(MArch);
528     }
529     return Triple.getTriple();
530   }
531   case llvm::Triple::aarch64: {
532     llvm::Triple Triple = getTriple();
533     if (!Triple.isOSBinFormatMachO())
534       return getTripleString();
535 
536     // FIXME: older versions of ld64 expect the "arm64" component in the actual
537     // triple string and query it to determine whether an LTO file can be
538     // handled. Remove this when we don't care any more.
539     Triple.setArchName("arm64");
540     return Triple.getTriple();
541   }
542   case llvm::Triple::arm:
543   case llvm::Triple::armeb:
544   case llvm::Triple::thumb:
545   case llvm::Triple::thumbeb: {
546     // FIXME: Factor into subclasses.
547     llvm::Triple Triple = getTriple();
548     bool IsBigEndian = getTriple().getArch() == llvm::Triple::armeb ||
549                        getTriple().getArch() == llvm::Triple::thumbeb;
550 
551     // Handle pseudo-target flags '-mlittle-endian'/'-EL' and
552     // '-mbig-endian'/'-EB'.
553     if (Arg *A = Args.getLastArg(options::OPT_mlittle_endian,
554                                  options::OPT_mbig_endian)) {
555       IsBigEndian = !A->getOption().matches(options::OPT_mlittle_endian);
556     }
557 
558     // Thumb2 is the default for V7 on Darwin.
559     //
560     // FIXME: Thumb should just be another -target-feaure, not in the triple.
561     StringRef MCPU, MArch;
562     if (const Arg *A = Args.getLastArg(options::OPT_mcpu_EQ))
563       MCPU = A->getValue();
564     if (const Arg *A = Args.getLastArg(options::OPT_march_EQ))
565       MArch = A->getValue();
566     std::string CPU =
567         Triple.isOSBinFormatMachO()
568             ? tools::arm::getARMCPUForMArch(MArch, Triple).str()
569             : tools::arm::getARMTargetCPU(MCPU, MArch, Triple);
570     StringRef Suffix =
571       tools::arm::getLLVMArchSuffixForARM(CPU, MArch, Triple);
572     bool IsMProfile = ARM::parseArchProfile(Suffix) == ARM::ProfileKind::M;
573     bool ThumbDefault = IsMProfile || (ARM::parseArchVersion(Suffix) == 7 &&
574                                        getTriple().isOSBinFormatMachO());
575     // FIXME: this is invalid for WindowsCE
576     if (getTriple().isOSWindows())
577       ThumbDefault = true;
578     std::string ArchName;
579     if (IsBigEndian)
580       ArchName = "armeb";
581     else
582       ArchName = "arm";
583 
584     // Check if ARM ISA was explicitly selected (using -mno-thumb or -marm) for
585     // M-Class CPUs/architecture variants, which is not supported.
586     bool ARMModeRequested = !Args.hasFlag(options::OPT_mthumb,
587                                           options::OPT_mno_thumb, ThumbDefault);
588     if (IsMProfile && ARMModeRequested) {
589       if (!MCPU.empty())
590         getDriver().Diag(diag::err_cpu_unsupported_isa) << CPU << "ARM";
591        else
592         getDriver().Diag(diag::err_arch_unsupported_isa)
593           << tools::arm::getARMArch(MArch, getTriple()) << "ARM";
594     }
595 
596     // Check to see if an explicit choice to use thumb has been made via
597     // -mthumb. For assembler files we must check for -mthumb in the options
598     // passed to the assember via -Wa or -Xassembler.
599     bool IsThumb = false;
600     if (InputType != types::TY_PP_Asm)
601       IsThumb = Args.hasFlag(options::OPT_mthumb, options::OPT_mno_thumb,
602                               ThumbDefault);
603     else {
604       // Ideally we would check for these flags in
605       // CollectArgsForIntegratedAssembler but we can't change the ArchName at
606       // that point. There is no assembler equivalent of -mno-thumb, -marm, or
607       // -mno-arm.
608       for (const auto *A :
609            Args.filtered(options::OPT_Wa_COMMA, options::OPT_Xassembler)) {
610         for (StringRef Value : A->getValues()) {
611           if (Value == "-mthumb")
612             IsThumb = true;
613         }
614       }
615     }
616     // Assembly files should start in ARM mode, unless arch is M-profile, or
617     // -mthumb has been passed explicitly to the assembler. Windows is always
618     // thumb.
619     if (IsThumb || IsMProfile || getTriple().isOSWindows()) {
620       if (IsBigEndian)
621         ArchName = "thumbeb";
622       else
623         ArchName = "thumb";
624     }
625     Triple.setArchName(ArchName + Suffix.str());
626 
627     return Triple.getTriple();
628   }
629   }
630 }
631 
632 std::string ToolChain::ComputeEffectiveClangTriple(const ArgList &Args,
633                                                    types::ID InputType) const {
634   return ComputeLLVMTriple(Args, InputType);
635 }
636 
637 void ToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
638                                           ArgStringList &CC1Args) const {
639   // Each toolchain should provide the appropriate include flags.
640 }
641 
642 void ToolChain::addClangTargetOptions(
643     const ArgList &DriverArgs, ArgStringList &CC1Args,
644     Action::OffloadKind DeviceOffloadKind) const {}
645 
646 void ToolChain::addClangWarningOptions(ArgStringList &CC1Args) const {}
647 
648 void ToolChain::addProfileRTLibs(const llvm::opt::ArgList &Args,
649                                  llvm::opt::ArgStringList &CmdArgs) const {
650   if (!needsProfileRT(Args)) return;
651 
652   CmdArgs.push_back(getCompilerRTArgString(Args, "profile"));
653 }
654 
655 ToolChain::RuntimeLibType ToolChain::GetRuntimeLibType(
656     const ArgList &Args) const {
657   const Arg* A = Args.getLastArg(options::OPT_rtlib_EQ);
658   StringRef LibName = A ? A->getValue() : CLANG_DEFAULT_RTLIB;
659 
660   // Only use "platform" in tests to override CLANG_DEFAULT_RTLIB!
661   if (LibName == "compiler-rt")
662     return ToolChain::RLT_CompilerRT;
663   else if (LibName == "libgcc")
664     return ToolChain::RLT_Libgcc;
665   else if (LibName == "platform")
666     return GetDefaultRuntimeLibType();
667 
668   if (A)
669     getDriver().Diag(diag::err_drv_invalid_rtlib_name) << A->getAsString(Args);
670 
671   return GetDefaultRuntimeLibType();
672 }
673 
674 ToolChain::CXXStdlibType ToolChain::GetCXXStdlibType(const ArgList &Args) const{
675   const Arg *A = Args.getLastArg(options::OPT_stdlib_EQ);
676   StringRef LibName = A ? A->getValue() : CLANG_DEFAULT_CXX_STDLIB;
677 
678   // Only use "platform" in tests to override CLANG_DEFAULT_CXX_STDLIB!
679   if (LibName == "libc++")
680     return ToolChain::CST_Libcxx;
681   else if (LibName == "libstdc++")
682     return ToolChain::CST_Libstdcxx;
683   else if (LibName == "platform")
684     return GetDefaultCXXStdlibType();
685 
686   if (A)
687     getDriver().Diag(diag::err_drv_invalid_stdlib_name) << A->getAsString(Args);
688 
689   return GetDefaultCXXStdlibType();
690 }
691 
692 /// Utility function to add a system include directory to CC1 arguments.
693 /*static*/ void ToolChain::addSystemInclude(const ArgList &DriverArgs,
694                                             ArgStringList &CC1Args,
695                                             const Twine &Path) {
696   CC1Args.push_back("-internal-isystem");
697   CC1Args.push_back(DriverArgs.MakeArgString(Path));
698 }
699 
700 /// Utility function to add a system include directory with extern "C"
701 /// semantics to CC1 arguments.
702 ///
703 /// Note that this should be used rarely, and only for directories that
704 /// historically and for legacy reasons are treated as having implicit extern
705 /// "C" semantics. These semantics are *ignored* by and large today, but its
706 /// important to preserve the preprocessor changes resulting from the
707 /// classification.
708 /*static*/ void ToolChain::addExternCSystemInclude(const ArgList &DriverArgs,
709                                                    ArgStringList &CC1Args,
710                                                    const Twine &Path) {
711   CC1Args.push_back("-internal-externc-isystem");
712   CC1Args.push_back(DriverArgs.MakeArgString(Path));
713 }
714 
715 void ToolChain::addExternCSystemIncludeIfExists(const ArgList &DriverArgs,
716                                                 ArgStringList &CC1Args,
717                                                 const Twine &Path) {
718   if (llvm::sys::fs::exists(Path))
719     addExternCSystemInclude(DriverArgs, CC1Args, Path);
720 }
721 
722 /// Utility function to add a list of system include directories to CC1.
723 /*static*/ void ToolChain::addSystemIncludes(const ArgList &DriverArgs,
724                                              ArgStringList &CC1Args,
725                                              ArrayRef<StringRef> Paths) {
726   for (const auto Path : Paths) {
727     CC1Args.push_back("-internal-isystem");
728     CC1Args.push_back(DriverArgs.MakeArgString(Path));
729   }
730 }
731 
732 void ToolChain::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
733                                              ArgStringList &CC1Args) const {
734   // Header search paths should be handled by each of the subclasses.
735   // Historically, they have not been, and instead have been handled inside of
736   // the CC1-layer frontend. As the logic is hoisted out, this generic function
737   // will slowly stop being called.
738   //
739   // While it is being called, replicate a bit of a hack to propagate the
740   // '-stdlib=' flag down to CC1 so that it can in turn customize the C++
741   // header search paths with it. Once all systems are overriding this
742   // function, the CC1 flag and this line can be removed.
743   DriverArgs.AddAllArgs(CC1Args, options::OPT_stdlib_EQ);
744 }
745 
746 bool ToolChain::ShouldLinkCXXStdlib(const llvm::opt::ArgList &Args) const {
747   return getDriver().CCCIsCXX() &&
748          !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs,
749                       options::OPT_nostdlibxx);
750 }
751 
752 void ToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
753                                     ArgStringList &CmdArgs) const {
754   assert(!Args.hasArg(options::OPT_nostdlibxx) &&
755          "should not have called this");
756   CXXStdlibType Type = GetCXXStdlibType(Args);
757 
758   switch (Type) {
759   case ToolChain::CST_Libcxx:
760     CmdArgs.push_back("-lc++");
761     break;
762 
763   case ToolChain::CST_Libstdcxx:
764     CmdArgs.push_back("-lstdc++");
765     break;
766   }
767 }
768 
769 void ToolChain::AddFilePathLibArgs(const ArgList &Args,
770                                    ArgStringList &CmdArgs) const {
771   for (const auto &LibPath : getLibraryPaths())
772     if(LibPath.length() > 0)
773       CmdArgs.push_back(Args.MakeArgString(StringRef("-L") + LibPath));
774 
775   for (const auto &LibPath : getFilePaths())
776     if(LibPath.length() > 0)
777       CmdArgs.push_back(Args.MakeArgString(StringRef("-L") + LibPath));
778 }
779 
780 void ToolChain::AddCCKextLibArgs(const ArgList &Args,
781                                  ArgStringList &CmdArgs) const {
782   CmdArgs.push_back("-lcc_kext");
783 }
784 
785 bool ToolChain::AddFastMathRuntimeIfAvailable(const ArgList &Args,
786                                               ArgStringList &CmdArgs) const {
787   // Do not check for -fno-fast-math or -fno-unsafe-math when -Ofast passed
788   // (to keep the linker options consistent with gcc and clang itself).
789   if (!isOptimizationLevelFast(Args)) {
790     // Check if -ffast-math or -funsafe-math.
791     Arg *A =
792         Args.getLastArg(options::OPT_ffast_math, options::OPT_fno_fast_math,
793                         options::OPT_funsafe_math_optimizations,
794                         options::OPT_fno_unsafe_math_optimizations);
795 
796     if (!A || A->getOption().getID() == options::OPT_fno_fast_math ||
797         A->getOption().getID() == options::OPT_fno_unsafe_math_optimizations)
798       return false;
799   }
800   // If crtfastmath.o exists add it to the arguments.
801   std::string Path = GetFilePath("crtfastmath.o");
802   if (Path == "crtfastmath.o") // Not found.
803     return false;
804 
805   CmdArgs.push_back(Args.MakeArgString(Path));
806   return true;
807 }
808 
809 SanitizerMask ToolChain::getSupportedSanitizers() const {
810   // Return sanitizers which don't require runtime support and are not
811   // platform dependent.
812 
813   using namespace SanitizerKind;
814 
815   SanitizerMask Res = (Undefined & ~Vptr & ~Function) | (CFI & ~CFIICall) |
816                       CFICastStrict | UnsignedIntegerOverflow |
817                       ImplicitConversion | Nullability | LocalBounds;
818   if (getTriple().getArch() == llvm::Triple::x86 ||
819       getTriple().getArch() == llvm::Triple::x86_64 ||
820       getTriple().getArch() == llvm::Triple::arm ||
821       getTriple().getArch() == llvm::Triple::aarch64 ||
822       getTriple().getArch() == llvm::Triple::wasm32 ||
823       getTriple().getArch() == llvm::Triple::wasm64)
824     Res |= CFIICall;
825   if (getTriple().getArch() == llvm::Triple::x86_64 ||
826       getTriple().getArch() == llvm::Triple::aarch64)
827     Res |= ShadowCallStack;
828   return Res;
829 }
830 
831 void ToolChain::AddCudaIncludeArgs(const ArgList &DriverArgs,
832                                    ArgStringList &CC1Args) const {}
833 
834 void ToolChain::AddIAMCUIncludeArgs(const ArgList &DriverArgs,
835                                     ArgStringList &CC1Args) const {}
836 
837 static VersionTuple separateMSVCFullVersion(unsigned Version) {
838   if (Version < 100)
839     return VersionTuple(Version);
840 
841   if (Version < 10000)
842     return VersionTuple(Version / 100, Version % 100);
843 
844   unsigned Build = 0, Factor = 1;
845   for (; Version > 10000; Version = Version / 10, Factor = Factor * 10)
846     Build = Build + (Version % 10) * Factor;
847   return VersionTuple(Version / 100, Version % 100, Build);
848 }
849 
850 VersionTuple
851 ToolChain::computeMSVCVersion(const Driver *D,
852                               const llvm::opt::ArgList &Args) const {
853   const Arg *MSCVersion = Args.getLastArg(options::OPT_fmsc_version);
854   const Arg *MSCompatibilityVersion =
855       Args.getLastArg(options::OPT_fms_compatibility_version);
856 
857   if (MSCVersion && MSCompatibilityVersion) {
858     if (D)
859       D->Diag(diag::err_drv_argument_not_allowed_with)
860           << MSCVersion->getAsString(Args)
861           << MSCompatibilityVersion->getAsString(Args);
862     return VersionTuple();
863   }
864 
865   if (MSCompatibilityVersion) {
866     VersionTuple MSVT;
867     if (MSVT.tryParse(MSCompatibilityVersion->getValue())) {
868       if (D)
869         D->Diag(diag::err_drv_invalid_value)
870             << MSCompatibilityVersion->getAsString(Args)
871             << MSCompatibilityVersion->getValue();
872     } else {
873       return MSVT;
874     }
875   }
876 
877   if (MSCVersion) {
878     unsigned Version = 0;
879     if (StringRef(MSCVersion->getValue()).getAsInteger(10, Version)) {
880       if (D)
881         D->Diag(diag::err_drv_invalid_value)
882             << MSCVersion->getAsString(Args) << MSCVersion->getValue();
883     } else {
884       return separateMSVCFullVersion(Version);
885     }
886   }
887 
888   return VersionTuple();
889 }
890 
891 llvm::opt::DerivedArgList *ToolChain::TranslateOpenMPTargetArgs(
892     const llvm::opt::DerivedArgList &Args, bool SameTripleAsHost,
893     SmallVectorImpl<llvm::opt::Arg *> &AllocatedArgs) const {
894   DerivedArgList *DAL = new DerivedArgList(Args.getBaseArgs());
895   const OptTable &Opts = getDriver().getOpts();
896   bool Modified = false;
897 
898   // Handle -Xopenmp-target flags
899   for (auto *A : Args) {
900     // Exclude flags which may only apply to the host toolchain.
901     // Do not exclude flags when the host triple (AuxTriple)
902     // matches the current toolchain triple. If it is not present
903     // at all, target and host share a toolchain.
904     if (A->getOption().matches(options::OPT_m_Group)) {
905       if (SameTripleAsHost)
906         DAL->append(A);
907       else
908         Modified = true;
909       continue;
910     }
911 
912     unsigned Index;
913     unsigned Prev;
914     bool XOpenMPTargetNoTriple =
915         A->getOption().matches(options::OPT_Xopenmp_target);
916 
917     if (A->getOption().matches(options::OPT_Xopenmp_target_EQ)) {
918       // Passing device args: -Xopenmp-target=<triple> -opt=val.
919       if (A->getValue(0) == getTripleString())
920         Index = Args.getBaseArgs().MakeIndex(A->getValue(1));
921       else
922         continue;
923     } else if (XOpenMPTargetNoTriple) {
924       // Passing device args: -Xopenmp-target -opt=val.
925       Index = Args.getBaseArgs().MakeIndex(A->getValue(0));
926     } else {
927       DAL->append(A);
928       continue;
929     }
930 
931     // Parse the argument to -Xopenmp-target.
932     Prev = Index;
933     std::unique_ptr<Arg> XOpenMPTargetArg(Opts.ParseOneArg(Args, Index));
934     if (!XOpenMPTargetArg || Index > Prev + 1) {
935       getDriver().Diag(diag::err_drv_invalid_Xopenmp_target_with_args)
936           << A->getAsString(Args);
937       continue;
938     }
939     if (XOpenMPTargetNoTriple && XOpenMPTargetArg &&
940         Args.getAllArgValues(options::OPT_fopenmp_targets_EQ).size() != 1) {
941       getDriver().Diag(diag::err_drv_Xopenmp_target_missing_triple);
942       continue;
943     }
944     XOpenMPTargetArg->setBaseArg(A);
945     A = XOpenMPTargetArg.release();
946     AllocatedArgs.push_back(A);
947     DAL->append(A);
948     Modified = true;
949   }
950 
951   if (Modified)
952     return DAL;
953 
954   delete DAL;
955   return nullptr;
956 }
957