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 "Tools.h"
11 #include "clang/Basic/ObjCRuntime.h"
12 #include "clang/Driver/Action.h"
13 #include "clang/Driver/Driver.h"
14 #include "clang/Driver/DriverDiagnostic.h"
15 #include "clang/Driver/Options.h"
16 #include "clang/Driver/SanitizerArgs.h"
17 #include "clang/Driver/ToolChain.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/StringSwitch.h"
20 #include "llvm/Option/Arg.h"
21 #include "llvm/Option/ArgList.h"
22 #include "llvm/Option/Option.h"
23 #include "llvm/Support/ErrorHandling.h"
24 #include "llvm/Support/FileSystem.h"
25 using namespace clang::driver;
26 using namespace clang;
27 using namespace llvm::opt;
28 
29 static llvm::opt::Arg *GetRTTIArgument(const ArgList &Args) {
30   return Args.getLastArg(options::OPT_mkernel, options::OPT_fapple_kext,
31                          options::OPT_fno_rtti, options::OPT_frtti);
32 }
33 
34 static ToolChain::RTTIMode CalculateRTTIMode(const ArgList &Args,
35                                              const llvm::Triple &Triple,
36                                              const Arg *CachedRTTIArg) {
37   // Explicit rtti/no-rtti args
38   if (CachedRTTIArg) {
39     if (CachedRTTIArg->getOption().matches(options::OPT_frtti))
40       return ToolChain::RM_EnabledExplicitly;
41     else
42       return ToolChain::RM_DisabledExplicitly;
43   }
44 
45   // -frtti is default, except for the PS4 CPU.
46   if (!Triple.isPS4CPU())
47     return ToolChain::RM_EnabledImplicitly;
48 
49   // On the PS4, turning on c++ exceptions turns on rtti.
50   // We're assuming that, if we see -fexceptions, rtti gets turned on.
51   Arg *Exceptions = Args.getLastArg(
52       options::OPT_fcxx_exceptions, options::OPT_fno_cxx_exceptions,
53       options::OPT_fexceptions, options::OPT_fno_exceptions);
54   if (Exceptions &&
55       (Exceptions->getOption().matches(options::OPT_fexceptions) ||
56        Exceptions->getOption().matches(options::OPT_fcxx_exceptions)))
57     return ToolChain::RM_EnabledImplicitly;
58 
59   return ToolChain::RM_DisabledImplicitly;
60 }
61 
62 ToolChain::ToolChain(const Driver &D, const llvm::Triple &T,
63                      const ArgList &Args)
64     : D(D), Triple(T), Args(Args), CachedRTTIArg(GetRTTIArgument(Args)),
65       CachedRTTIMode(CalculateRTTIMode(Args, Triple, CachedRTTIArg)) {
66   if (Arg *A = Args.getLastArg(options::OPT_mthread_model))
67     if (!isThreadModelSupported(A->getValue()))
68       D.Diag(diag::err_drv_invalid_thread_model_for_target)
69           << A->getValue() << A->getAsString(Args);
70 }
71 
72 ToolChain::~ToolChain() {
73 }
74 
75 const Driver &ToolChain::getDriver() const {
76  return D;
77 }
78 
79 bool ToolChain::useIntegratedAs() const {
80   return Args.hasFlag(options::OPT_fintegrated_as,
81                       options::OPT_fno_integrated_as,
82                       IsIntegratedAssemblerDefault());
83 }
84 
85 const SanitizerArgs& ToolChain::getSanitizerArgs() const {
86   if (!SanitizerArguments.get())
87     SanitizerArguments.reset(new SanitizerArgs(*this, Args));
88   return *SanitizerArguments.get();
89 }
90 
91 StringRef ToolChain::getDefaultUniversalArchName() const {
92   // In universal driver terms, the arch name accepted by -arch isn't exactly
93   // the same as the ones that appear in the triple. Roughly speaking, this is
94   // an inverse of the darwin::getArchTypeForDarwinArchName() function, but the
95   // only interesting special case is powerpc.
96   switch (Triple.getArch()) {
97   case llvm::Triple::ppc:
98     return "ppc";
99   case llvm::Triple::ppc64:
100     return "ppc64";
101   case llvm::Triple::ppc64le:
102     return "ppc64le";
103   default:
104     return Triple.getArchName();
105   }
106 }
107 
108 bool ToolChain::IsUnwindTablesDefault() const {
109   return false;
110 }
111 
112 Tool *ToolChain::getClang() const {
113   if (!Clang)
114     Clang.reset(new tools::Clang(*this));
115   return Clang.get();
116 }
117 
118 Tool *ToolChain::buildAssembler() const {
119   return new tools::ClangAs(*this);
120 }
121 
122 Tool *ToolChain::buildLinker() const {
123   llvm_unreachable("Linking is not supported by this toolchain");
124 }
125 
126 Tool *ToolChain::getAssemble() const {
127   if (!Assemble)
128     Assemble.reset(buildAssembler());
129   return Assemble.get();
130 }
131 
132 Tool *ToolChain::getClangAs() const {
133   if (!Assemble)
134     Assemble.reset(new tools::ClangAs(*this));
135   return Assemble.get();
136 }
137 
138 Tool *ToolChain::getLink() const {
139   if (!Link)
140     Link.reset(buildLinker());
141   return Link.get();
142 }
143 
144 Tool *ToolChain::getTool(Action::ActionClass AC) const {
145   switch (AC) {
146   case Action::AssembleJobClass:
147     return getAssemble();
148 
149   case Action::LinkJobClass:
150     return getLink();
151 
152   case Action::InputClass:
153   case Action::BindArchClass:
154   case Action::LipoJobClass:
155   case Action::DsymutilJobClass:
156   case Action::VerifyDebugInfoJobClass:
157     llvm_unreachable("Invalid tool kind.");
158 
159   case Action::CompileJobClass:
160   case Action::PrecompileJobClass:
161   case Action::PreprocessJobClass:
162   case Action::AnalyzeJobClass:
163   case Action::MigrateJobClass:
164   case Action::VerifyPCHJobClass:
165   case Action::BackendJobClass:
166     return getClang();
167   }
168 
169   llvm_unreachable("Invalid tool kind.");
170 }
171 
172 Tool *ToolChain::SelectTool(const JobAction &JA) const {
173   if (getDriver().ShouldUseClangCompiler(JA))
174     return getClang();
175   Action::ActionClass AC = JA.getKind();
176   if (AC == Action::AssembleJobClass && useIntegratedAs())
177     return getClangAs();
178   return getTool(AC);
179 }
180 
181 std::string ToolChain::GetFilePath(const char *Name) const {
182   return D.GetFilePath(Name, *this);
183 
184 }
185 
186 std::string ToolChain::GetProgramPath(const char *Name) const {
187   return D.GetProgramPath(Name, *this);
188 }
189 
190 std::string ToolChain::GetLinkerPath() const {
191   if (Arg *A = Args.getLastArg(options::OPT_fuse_ld_EQ)) {
192     StringRef Suffix = A->getValue();
193 
194     // If we're passed -fuse-ld= with no argument, or with the argument ld,
195     // then use whatever the default system linker is.
196     if (Suffix.empty() || Suffix == "ld")
197       return GetProgramPath("ld");
198 
199     llvm::SmallString<8> LinkerName("ld.");
200     LinkerName.append(Suffix);
201 
202     std::string LinkerPath(GetProgramPath(LinkerName.c_str()));
203     if (llvm::sys::fs::exists(LinkerPath))
204       return LinkerPath;
205 
206     getDriver().Diag(diag::err_drv_invalid_linker_name) << A->getAsString(Args);
207     return "";
208   }
209 
210   return GetProgramPath("ld");
211 }
212 
213 
214 types::ID ToolChain::LookupTypeForExtension(const char *Ext) const {
215   return types::lookupTypeForExtension(Ext);
216 }
217 
218 bool ToolChain::HasNativeLLVMSupport() const {
219   return false;
220 }
221 
222 bool ToolChain::isCrossCompiling() const {
223   llvm::Triple HostTriple(LLVM_HOST_TRIPLE);
224   switch (HostTriple.getArch()) {
225   // The A32/T32/T16 instruction sets are not separate architectures in this
226   // context.
227   case llvm::Triple::arm:
228   case llvm::Triple::armeb:
229   case llvm::Triple::thumb:
230   case llvm::Triple::thumbeb:
231     return getArch() != llvm::Triple::arm && getArch() != llvm::Triple::thumb &&
232            getArch() != llvm::Triple::armeb && getArch() != llvm::Triple::thumbeb;
233   default:
234     return HostTriple.getArch() != getArch();
235   }
236 }
237 
238 ObjCRuntime ToolChain::getDefaultObjCRuntime(bool isNonFragile) const {
239   return ObjCRuntime(isNonFragile ? ObjCRuntime::GNUstep : ObjCRuntime::GCC,
240                      VersionTuple());
241 }
242 
243 bool ToolChain::isThreadModelSupported(const StringRef Model) const {
244   if (Model == "single") {
245     // FIXME: 'single' is only supported on ARM so far.
246     return Triple.getArch() == llvm::Triple::arm ||
247            Triple.getArch() == llvm::Triple::armeb ||
248            Triple.getArch() == llvm::Triple::thumb ||
249            Triple.getArch() == llvm::Triple::thumbeb;
250   } else if (Model == "posix")
251     return true;
252 
253   return false;
254 }
255 
256 std::string ToolChain::ComputeLLVMTriple(const ArgList &Args,
257                                          types::ID InputType) const {
258   switch (getTriple().getArch()) {
259   default:
260     return getTripleString();
261 
262   case llvm::Triple::x86_64: {
263     llvm::Triple Triple = getTriple();
264     if (!Triple.isOSBinFormatMachO())
265       return getTripleString();
266 
267     if (Arg *A = Args.getLastArg(options::OPT_march_EQ)) {
268       // x86_64h goes in the triple. Other -march options just use the
269       // vanilla triple we already have.
270       StringRef MArch = A->getValue();
271       if (MArch == "x86_64h")
272         Triple.setArchName(MArch);
273     }
274     return Triple.getTriple();
275   }
276   case llvm::Triple::aarch64: {
277     llvm::Triple Triple = getTriple();
278     if (!Triple.isOSBinFormatMachO())
279       return getTripleString();
280 
281     // FIXME: older versions of ld64 expect the "arm64" component in the actual
282     // triple string and query it to determine whether an LTO file can be
283     // handled. Remove this when we don't care any more.
284     Triple.setArchName("arm64");
285     return Triple.getTriple();
286   }
287   case llvm::Triple::arm:
288   case llvm::Triple::armeb:
289   case llvm::Triple::thumb:
290   case llvm::Triple::thumbeb: {
291     // FIXME: Factor into subclasses.
292     llvm::Triple Triple = getTriple();
293     bool IsBigEndian = getTriple().getArch() == llvm::Triple::armeb ||
294                        getTriple().getArch() == llvm::Triple::thumbeb;
295 
296     // Handle pseudo-target flags '-mlittle-endian'/'-EL' and
297     // '-mbig-endian'/'-EB'.
298     if (Arg *A = Args.getLastArg(options::OPT_mlittle_endian,
299                                  options::OPT_mbig_endian)) {
300       if (A->getOption().matches(options::OPT_mlittle_endian))
301         IsBigEndian = false;
302       else
303         IsBigEndian = true;
304     }
305 
306     // Thumb2 is the default for V7 on Darwin.
307     //
308     // FIXME: Thumb should just be another -target-feaure, not in the triple.
309     StringRef Suffix = Triple.isOSBinFormatMachO()
310       ? tools::arm::getLLVMArchSuffixForARM(tools::arm::getARMCPUForMArch(Args, Triple))
311       : tools::arm::getLLVMArchSuffixForARM(tools::arm::getARMTargetCPU(Args, Triple));
312     bool ThumbDefault = Suffix.startswith("v6m") || Suffix.startswith("v7m") ||
313       Suffix.startswith("v7em") ||
314       (Suffix.startswith("v7") && getTriple().isOSBinFormatMachO());
315     // FIXME: this is invalid for WindowsCE
316     if (getTriple().isOSWindows())
317       ThumbDefault = true;
318     std::string ArchName;
319     if (IsBigEndian)
320       ArchName = "armeb";
321     else
322       ArchName = "arm";
323 
324     // Assembly files should start in ARM mode.
325     if (InputType != types::TY_PP_Asm &&
326         Args.hasFlag(options::OPT_mthumb, options::OPT_mno_thumb, ThumbDefault))
327     {
328       if (IsBigEndian)
329         ArchName = "thumbeb";
330       else
331         ArchName = "thumb";
332     }
333     Triple.setArchName(ArchName + Suffix.str());
334 
335     return Triple.getTriple();
336   }
337   }
338 }
339 
340 std::string ToolChain::ComputeEffectiveClangTriple(const ArgList &Args,
341                                                    types::ID InputType) const {
342   return ComputeLLVMTriple(Args, InputType);
343 }
344 
345 void ToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
346                                           ArgStringList &CC1Args) const {
347   // Each toolchain should provide the appropriate include flags.
348 }
349 
350 void ToolChain::addClangTargetOptions(const ArgList &DriverArgs,
351                                       ArgStringList &CC1Args) const {
352 }
353 
354 void ToolChain::addClangWarningOptions(ArgStringList &CC1Args) const {}
355 
356 ToolChain::RuntimeLibType ToolChain::GetRuntimeLibType(
357   const ArgList &Args) const
358 {
359   if (Arg *A = Args.getLastArg(options::OPT_rtlib_EQ)) {
360     StringRef Value = A->getValue();
361     if (Value == "compiler-rt")
362       return ToolChain::RLT_CompilerRT;
363     if (Value == "libgcc")
364       return ToolChain::RLT_Libgcc;
365     getDriver().Diag(diag::err_drv_invalid_rtlib_name)
366       << A->getAsString(Args);
367   }
368 
369   return GetDefaultRuntimeLibType();
370 }
371 
372 ToolChain::CXXStdlibType ToolChain::GetCXXStdlibType(const ArgList &Args) const{
373   if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) {
374     StringRef Value = A->getValue();
375     if (Value == "libc++")
376       return ToolChain::CST_Libcxx;
377     if (Value == "libstdc++")
378       return ToolChain::CST_Libstdcxx;
379     getDriver().Diag(diag::err_drv_invalid_stdlib_name)
380       << A->getAsString(Args);
381   }
382 
383   return ToolChain::CST_Libstdcxx;
384 }
385 
386 /// \brief Utility function to add a system include directory to CC1 arguments.
387 /*static*/ void ToolChain::addSystemInclude(const ArgList &DriverArgs,
388                                             ArgStringList &CC1Args,
389                                             const Twine &Path) {
390   CC1Args.push_back("-internal-isystem");
391   CC1Args.push_back(DriverArgs.MakeArgString(Path));
392 }
393 
394 /// \brief Utility function to add a system include directory with extern "C"
395 /// semantics to CC1 arguments.
396 ///
397 /// Note that this should be used rarely, and only for directories that
398 /// historically and for legacy reasons are treated as having implicit extern
399 /// "C" semantics. These semantics are *ignored* by and large today, but its
400 /// important to preserve the preprocessor changes resulting from the
401 /// classification.
402 /*static*/ void ToolChain::addExternCSystemInclude(const ArgList &DriverArgs,
403                                                    ArgStringList &CC1Args,
404                                                    const Twine &Path) {
405   CC1Args.push_back("-internal-externc-isystem");
406   CC1Args.push_back(DriverArgs.MakeArgString(Path));
407 }
408 
409 void ToolChain::addExternCSystemIncludeIfExists(const ArgList &DriverArgs,
410                                                 ArgStringList &CC1Args,
411                                                 const Twine &Path) {
412   if (llvm::sys::fs::exists(Path))
413     addExternCSystemInclude(DriverArgs, CC1Args, Path);
414 }
415 
416 /// \brief Utility function to add a list of system include directories to CC1.
417 /*static*/ void ToolChain::addSystemIncludes(const ArgList &DriverArgs,
418                                              ArgStringList &CC1Args,
419                                              ArrayRef<StringRef> Paths) {
420   for (ArrayRef<StringRef>::iterator I = Paths.begin(), E = Paths.end();
421        I != E; ++I) {
422     CC1Args.push_back("-internal-isystem");
423     CC1Args.push_back(DriverArgs.MakeArgString(*I));
424   }
425 }
426 
427 void ToolChain::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
428                                              ArgStringList &CC1Args) const {
429   // Header search paths should be handled by each of the subclasses.
430   // Historically, they have not been, and instead have been handled inside of
431   // the CC1-layer frontend. As the logic is hoisted out, this generic function
432   // will slowly stop being called.
433   //
434   // While it is being called, replicate a bit of a hack to propagate the
435   // '-stdlib=' flag down to CC1 so that it can in turn customize the C++
436   // header search paths with it. Once all systems are overriding this
437   // function, the CC1 flag and this line can be removed.
438   DriverArgs.AddAllArgs(CC1Args, options::OPT_stdlib_EQ);
439 }
440 
441 void ToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
442                                     ArgStringList &CmdArgs) const {
443   CXXStdlibType Type = GetCXXStdlibType(Args);
444 
445   switch (Type) {
446   case ToolChain::CST_Libcxx:
447     CmdArgs.push_back("-lc++");
448     break;
449 
450   case ToolChain::CST_Libstdcxx:
451     CmdArgs.push_back("-lstdc++");
452     break;
453   }
454 }
455 
456 void ToolChain::AddCCKextLibArgs(const ArgList &Args,
457                                  ArgStringList &CmdArgs) const {
458   CmdArgs.push_back("-lcc_kext");
459 }
460 
461 bool ToolChain::AddFastMathRuntimeIfAvailable(const ArgList &Args,
462                                               ArgStringList &CmdArgs) const {
463   // Do not check for -fno-fast-math or -fno-unsafe-math when -Ofast passed
464   // (to keep the linker options consistent with gcc and clang itself).
465   if (!isOptimizationLevelFast(Args)) {
466     // Check if -ffast-math or -funsafe-math.
467     Arg *A =
468         Args.getLastArg(options::OPT_ffast_math, options::OPT_fno_fast_math,
469                         options::OPT_funsafe_math_optimizations,
470                         options::OPT_fno_unsafe_math_optimizations);
471 
472     if (!A || A->getOption().getID() == options::OPT_fno_fast_math ||
473         A->getOption().getID() == options::OPT_fno_unsafe_math_optimizations)
474       return false;
475   }
476   // If crtfastmath.o exists add it to the arguments.
477   std::string Path = GetFilePath("crtfastmath.o");
478   if (Path == "crtfastmath.o") // Not found.
479     return false;
480 
481   CmdArgs.push_back(Args.MakeArgString(Path));
482   return true;
483 }
484