xref: /freebsd/contrib/llvm-project/clang/lib/Driver/ToolChains/Gnu.cpp (revision b64c5a0ace59af62eff52bfe110a521dc73c937b) 
1 //===--- Gnu.cpp - Gnu Tool and ToolChain Implementations -------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "Gnu.h"
10 #include "Arch/ARM.h"
11 #include "Arch/CSKY.h"
12 #include "Arch/LoongArch.h"
13 #include "Arch/Mips.h"
14 #include "Arch/PPC.h"
15 #include "Arch/RISCV.h"
16 #include "Arch/Sparc.h"
17 #include "Arch/SystemZ.h"
18 #include "CommonArgs.h"
19 #include "Linux.h"
20 #include "clang/Config/config.h" // for GCC_INSTALL_PREFIX
21 #include "clang/Driver/Compilation.h"
22 #include "clang/Driver/Driver.h"
23 #include "clang/Driver/DriverDiagnostic.h"
24 #include "clang/Driver/MultilibBuilder.h"
25 #include "clang/Driver/Options.h"
26 #include "clang/Driver/Tool.h"
27 #include "clang/Driver/ToolChain.h"
28 #include "llvm/ADT/StringSet.h"
29 #include "llvm/ADT/Twine.h"
30 #include "llvm/Option/ArgList.h"
31 #include "llvm/Support/CodeGen.h"
32 #include "llvm/Support/Path.h"
33 #include "llvm/Support/VirtualFileSystem.h"
34 #include "llvm/TargetParser/RISCVISAInfo.h"
35 #include "llvm/TargetParser/TargetParser.h"
36 #include <system_error>
37 
38 using namespace clang::driver;
39 using namespace clang::driver::toolchains;
40 using namespace clang;
41 using namespace llvm::opt;
42 
43 using tools::addMultilibFlag;
44 using tools::addPathIfExists;
45 
46 static bool forwardToGCC(const Option &O) {
47   // LinkerInput options have been forwarded. Don't duplicate.
48   if (O.hasFlag(options::LinkerInput))
49     return false;
50   return O.matches(options::OPT_Link_Group) || O.hasFlag(options::LinkOption);
51 }
52 
53 // Switch CPU names not recognized by GNU assembler to a close CPU that it does
54 // recognize, instead of a lower march from being picked in the absence of a cpu
55 // flag.
56 static void normalizeCPUNamesForAssembler(const ArgList &Args,
57                                           ArgStringList &CmdArgs) {
58   if (Arg *A = Args.getLastArg(options::OPT_mcpu_EQ)) {
59     StringRef CPUArg(A->getValue());
60     if (CPUArg.equals_insensitive("krait"))
61       CmdArgs.push_back("-mcpu=cortex-a15");
62     else if (CPUArg.equals_insensitive("kryo"))
63       CmdArgs.push_back("-mcpu=cortex-a57");
64     else
65       Args.AddLastArg(CmdArgs, options::OPT_mcpu_EQ);
66   }
67 }
68 
69 void tools::gcc::Common::ConstructJob(Compilation &C, const JobAction &JA,
70                                       const InputInfo &Output,
71                                       const InputInfoList &Inputs,
72                                       const ArgList &Args,
73                                       const char *LinkingOutput) const {
74   const Driver &D = getToolChain().getDriver();
75   ArgStringList CmdArgs;
76 
77   for (const auto &A : Args) {
78     if (forwardToGCC(A->getOption())) {
79       // It is unfortunate that we have to claim here, as this means
80       // we will basically never report anything interesting for
81       // platforms using a generic gcc, even if we are just using gcc
82       // to get to the assembler.
83       A->claim();
84 
85       A->render(Args, CmdArgs);
86     }
87   }
88 
89   RenderExtraToolArgs(JA, CmdArgs);
90 
91   // If using a driver, force the arch.
92   if (getToolChain().getTriple().isOSDarwin()) {
93     CmdArgs.push_back("-arch");
94     CmdArgs.push_back(
95         Args.MakeArgString(getToolChain().getDefaultUniversalArchName()));
96   }
97 
98   // Try to force gcc to match the tool chain we want, if we recognize
99   // the arch.
100   //
101   // FIXME: The triple class should directly provide the information we want
102   // here.
103   switch (getToolChain().getArch()) {
104   default:
105     break;
106   case llvm::Triple::x86:
107   case llvm::Triple::ppc:
108   case llvm::Triple::ppcle:
109     CmdArgs.push_back("-m32");
110     break;
111   case llvm::Triple::x86_64:
112   case llvm::Triple::ppc64:
113   case llvm::Triple::ppc64le:
114     CmdArgs.push_back("-m64");
115     break;
116   case llvm::Triple::sparcel:
117     CmdArgs.push_back("-EL");
118     break;
119   }
120 
121   assert((Output.isFilename() || Output.isNothing()) && "Invalid output.");
122   if (Output.isFilename()) {
123     CmdArgs.push_back("-o");
124     CmdArgs.push_back(Output.getFilename());
125   } else {
126     CmdArgs.push_back("-fsyntax-only");
127   }
128 
129   Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
130 
131   // Only pass -x if gcc will understand it; otherwise hope gcc
132   // understands the suffix correctly. The main use case this would go
133   // wrong in is for linker inputs if they happened to have an odd
134   // suffix; really the only way to get this to happen is a command
135   // like '-x foobar a.c' which will treat a.c like a linker input.
136   //
137   // FIXME: For the linker case specifically, can we safely convert
138   // inputs into '-Wl,' options?
139   for (const auto &II : Inputs) {
140     // Don't try to pass LLVM or AST inputs to a generic gcc.
141     if (types::isLLVMIR(II.getType()))
142       D.Diag(clang::diag::err_drv_no_linker_llvm_support)
143           << getToolChain().getTripleString();
144     else if (II.getType() == types::TY_AST)
145       D.Diag(diag::err_drv_no_ast_support) << getToolChain().getTripleString();
146     else if (II.getType() == types::TY_ModuleFile)
147       D.Diag(diag::err_drv_no_module_support)
148           << getToolChain().getTripleString();
149 
150     if (types::canTypeBeUserSpecified(II.getType())) {
151       CmdArgs.push_back("-x");
152       CmdArgs.push_back(types::getTypeName(II.getType()));
153     }
154 
155     if (II.isFilename())
156       CmdArgs.push_back(II.getFilename());
157     else {
158       const Arg &A = II.getInputArg();
159 
160       // Reverse translate some rewritten options.
161       if (A.getOption().matches(options::OPT_Z_reserved_lib_stdcxx)) {
162         CmdArgs.push_back("-lstdc++");
163         continue;
164       }
165 
166       // Don't render as input, we need gcc to do the translations.
167       A.render(Args, CmdArgs);
168     }
169   }
170 
171   const std::string &customGCCName = D.getCCCGenericGCCName();
172   const char *GCCName;
173   if (!customGCCName.empty())
174     GCCName = customGCCName.c_str();
175   else if (D.CCCIsCXX()) {
176     GCCName = "g++";
177   } else
178     GCCName = "gcc";
179 
180   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath(GCCName));
181   C.addCommand(std::make_unique<Command>(JA, *this,
182                                          ResponseFileSupport::AtFileCurCP(),
183                                          Exec, CmdArgs, Inputs, Output));
184 }
185 
186 void tools::gcc::Preprocessor::RenderExtraToolArgs(
187     const JobAction &JA, ArgStringList &CmdArgs) const {
188   CmdArgs.push_back("-E");
189 }
190 
191 void tools::gcc::Compiler::RenderExtraToolArgs(const JobAction &JA,
192                                                ArgStringList &CmdArgs) const {
193   const Driver &D = getToolChain().getDriver();
194 
195   switch (JA.getType()) {
196   // If -flto, etc. are present then make sure not to force assembly output.
197   case types::TY_LLVM_IR:
198   case types::TY_LTO_IR:
199   case types::TY_LLVM_BC:
200   case types::TY_LTO_BC:
201     CmdArgs.push_back("-c");
202     break;
203   // We assume we've got an "integrated" assembler in that gcc will produce an
204   // object file itself.
205   case types::TY_Object:
206     CmdArgs.push_back("-c");
207     break;
208   case types::TY_PP_Asm:
209     CmdArgs.push_back("-S");
210     break;
211   case types::TY_Nothing:
212     CmdArgs.push_back("-fsyntax-only");
213     break;
214   default:
215     D.Diag(diag::err_drv_invalid_gcc_output_type) << getTypeName(JA.getType());
216   }
217 }
218 
219 void tools::gcc::Linker::RenderExtraToolArgs(const JobAction &JA,
220                                              ArgStringList &CmdArgs) const {
221   // The types are (hopefully) good enough.
222 }
223 
224 static const char *getLDMOption(const llvm::Triple &T, const ArgList &Args) {
225   switch (T.getArch()) {
226   case llvm::Triple::x86:
227     if (T.isOSIAMCU())
228       return "elf_iamcu";
229     return "elf_i386";
230   case llvm::Triple::aarch64:
231     return "aarch64linux";
232   case llvm::Triple::aarch64_be:
233     return "aarch64linuxb";
234   case llvm::Triple::arm:
235   case llvm::Triple::thumb:
236   case llvm::Triple::armeb:
237   case llvm::Triple::thumbeb:
238     return tools::arm::isARMBigEndian(T, Args) ? "armelfb_linux_eabi"
239                                                : "armelf_linux_eabi";
240   case llvm::Triple::m68k:
241     return "m68kelf";
242   case llvm::Triple::ppc:
243     if (T.isOSLinux())
244       return "elf32ppclinux";
245     return "elf32ppc";
246   case llvm::Triple::ppcle:
247     if (T.isOSLinux())
248       return "elf32lppclinux";
249     return "elf32lppc";
250   case llvm::Triple::ppc64:
251     return "elf64ppc";
252   case llvm::Triple::ppc64le:
253     return "elf64lppc";
254   case llvm::Triple::riscv32:
255     return "elf32lriscv";
256   case llvm::Triple::riscv64:
257     return "elf64lriscv";
258   case llvm::Triple::sparc:
259   case llvm::Triple::sparcel:
260     return "elf32_sparc";
261   case llvm::Triple::sparcv9:
262     return "elf64_sparc";
263   case llvm::Triple::loongarch32:
264     return "elf32loongarch";
265   case llvm::Triple::loongarch64:
266     return "elf64loongarch";
267   case llvm::Triple::mips:
268     return "elf32btsmip";
269   case llvm::Triple::mipsel:
270     return "elf32ltsmip";
271   case llvm::Triple::mips64:
272     if (tools::mips::hasMipsAbiArg(Args, "n32") ||
273         T.getEnvironment() == llvm::Triple::GNUABIN32)
274       return "elf32btsmipn32";
275     return "elf64btsmip";
276   case llvm::Triple::mips64el:
277     if (tools::mips::hasMipsAbiArg(Args, "n32") ||
278         T.getEnvironment() == llvm::Triple::GNUABIN32)
279       return "elf32ltsmipn32";
280     return "elf64ltsmip";
281   case llvm::Triple::systemz:
282     return "elf64_s390";
283   case llvm::Triple::x86_64:
284     if (T.isX32())
285       return "elf32_x86_64";
286     return "elf_x86_64";
287   case llvm::Triple::ve:
288     return "elf64ve";
289   case llvm::Triple::csky:
290     return "cskyelf_linux";
291   default:
292     return nullptr;
293   }
294 }
295 
296 static bool getStaticPIE(const ArgList &Args, const ToolChain &TC) {
297   bool HasStaticPIE = Args.hasArg(options::OPT_static_pie);
298   if (HasStaticPIE && Args.hasArg(options::OPT_no_pie)) {
299     const Driver &D = TC.getDriver();
300     const llvm::opt::OptTable &Opts = D.getOpts();
301     StringRef StaticPIEName = Opts.getOptionName(options::OPT_static_pie);
302     StringRef NoPIEName = Opts.getOptionName(options::OPT_nopie);
303     D.Diag(diag::err_drv_cannot_mix_options) << StaticPIEName << NoPIEName;
304   }
305   return HasStaticPIE;
306 }
307 
308 static bool getStatic(const ArgList &Args) {
309   return Args.hasArg(options::OPT_static) &&
310       !Args.hasArg(options::OPT_static_pie);
311 }
312 
313 void tools::gnutools::StaticLibTool::ConstructJob(
314     Compilation &C, const JobAction &JA, const InputInfo &Output,
315     const InputInfoList &Inputs, const ArgList &Args,
316     const char *LinkingOutput) const {
317   const Driver &D = getToolChain().getDriver();
318 
319   // Silence warning for "clang -g foo.o -o foo"
320   Args.ClaimAllArgs(options::OPT_g_Group);
321   // and "clang -emit-llvm foo.o -o foo"
322   Args.ClaimAllArgs(options::OPT_emit_llvm);
323   // and for "clang -w foo.o -o foo". Other warning options are already
324   // handled somewhere else.
325   Args.ClaimAllArgs(options::OPT_w);
326   // Silence warnings when linking C code with a C++ '-stdlib' argument.
327   Args.ClaimAllArgs(options::OPT_stdlib_EQ);
328 
329   // ar tool command "llvm-ar <options> <output_file> <input_files>".
330   ArgStringList CmdArgs;
331   // Create and insert file members with a deterministic index.
332   CmdArgs.push_back("rcsD");
333   CmdArgs.push_back(Output.getFilename());
334 
335   for (const auto &II : Inputs) {
336     if (II.isFilename()) {
337        CmdArgs.push_back(II.getFilename());
338     }
339   }
340 
341   // Delete old output archive file if it already exists before generating a new
342   // archive file.
343   auto OutputFileName = Output.getFilename();
344   if (Output.isFilename() && llvm::sys::fs::exists(OutputFileName)) {
345     if (std::error_code EC = llvm::sys::fs::remove(OutputFileName)) {
346       D.Diag(diag::err_drv_unable_to_remove_file) << EC.message();
347       return;
348     }
349   }
350 
351   const char *Exec = Args.MakeArgString(getToolChain().GetStaticLibToolPath());
352   C.addCommand(std::make_unique<Command>(JA, *this,
353                                          ResponseFileSupport::AtFileCurCP(),
354                                          Exec, CmdArgs, Inputs, Output));
355 }
356 
357 void tools::gnutools::Linker::ConstructJob(Compilation &C, const JobAction &JA,
358                                            const InputInfo &Output,
359                                            const InputInfoList &Inputs,
360                                            const ArgList &Args,
361                                            const char *LinkingOutput) const {
362   // FIXME: The Linker class constructor takes a ToolChain and not a
363   // Generic_ELF, so the static_cast might return a reference to a invalid
364   // instance (see PR45061). Ideally, the Linker constructor needs to take a
365   // Generic_ELF instead.
366   const auto &ToolChain = static_cast<const Generic_ELF &>(getToolChain());
367   const Driver &D = ToolChain.getDriver();
368 
369   const llvm::Triple &Triple = getToolChain().getEffectiveTriple();
370 
371   const llvm::Triple::ArchType Arch = ToolChain.getArch();
372   const bool isOHOSFamily = ToolChain.getTriple().isOHOSFamily();
373   const bool isAndroid = ToolChain.getTriple().isAndroid();
374   const bool IsIAMCU = ToolChain.getTriple().isOSIAMCU();
375   const bool IsVE = ToolChain.getTriple().isVE();
376   const bool IsStaticPIE = getStaticPIE(Args, ToolChain);
377   const bool IsStatic = getStatic(Args);
378   const bool HasCRTBeginEndFiles =
379       ToolChain.getTriple().hasEnvironment() ||
380       (ToolChain.getTriple().getVendor() != llvm::Triple::MipsTechnologies);
381 
382   ArgStringList CmdArgs;
383 
384   // Silence warning for "clang -g foo.o -o foo"
385   Args.ClaimAllArgs(options::OPT_g_Group);
386   // and "clang -emit-llvm foo.o -o foo"
387   Args.ClaimAllArgs(options::OPT_emit_llvm);
388   // and for "clang -w foo.o -o foo". Other warning options are already
389   // handled somewhere else.
390   Args.ClaimAllArgs(options::OPT_w);
391 
392   if (!D.SysRoot.empty())
393     CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
394 
395   if (Args.hasArg(options::OPT_s))
396     CmdArgs.push_back("-s");
397 
398   if (Triple.isARM() || Triple.isThumb()) {
399     bool IsBigEndian = arm::isARMBigEndian(Triple, Args);
400     if (IsBigEndian)
401       arm::appendBE8LinkFlag(Args, CmdArgs, Triple);
402     CmdArgs.push_back(IsBigEndian ? "-EB" : "-EL");
403   } else if (Triple.isAArch64()) {
404     CmdArgs.push_back(Arch == llvm::Triple::aarch64_be ? "-EB" : "-EL");
405   }
406 
407   // Most Android ARM64 targets should enable the linker fix for erratum
408   // 843419. Only non-Cortex-A53 devices are allowed to skip this flag.
409   if (Arch == llvm::Triple::aarch64 && (isAndroid || isOHOSFamily)) {
410     std::string CPU = getCPUName(D, Args, Triple);
411     if (CPU.empty() || CPU == "generic" || CPU == "cortex-a53")
412       CmdArgs.push_back("--fix-cortex-a53-843419");
413   }
414 
415   ToolChain.addExtraOpts(CmdArgs);
416 
417   CmdArgs.push_back("--eh-frame-hdr");
418 
419   if (const char *LDMOption = getLDMOption(ToolChain.getTriple(), Args)) {
420     CmdArgs.push_back("-m");
421     CmdArgs.push_back(LDMOption);
422   } else {
423     D.Diag(diag::err_target_unknown_triple) << Triple.str();
424     return;
425   }
426 
427   if (Triple.isRISCV()) {
428     CmdArgs.push_back("-X");
429     if (Args.hasArg(options::OPT_mno_relax))
430       CmdArgs.push_back("--no-relax");
431   }
432 
433   const bool IsShared = Args.hasArg(options::OPT_shared);
434   if (IsShared)
435     CmdArgs.push_back("-shared");
436   bool IsPIE = false;
437   if (IsStaticPIE) {
438     CmdArgs.push_back("-static");
439     CmdArgs.push_back("-pie");
440     CmdArgs.push_back("--no-dynamic-linker");
441     CmdArgs.push_back("-z");
442     CmdArgs.push_back("text");
443   } else if (IsStatic) {
444     CmdArgs.push_back("-static");
445   } else if (!Args.hasArg(options::OPT_r)) {
446     if (Args.hasArg(options::OPT_rdynamic))
447       CmdArgs.push_back("-export-dynamic");
448     if (!IsShared) {
449       IsPIE = Args.hasFlag(options::OPT_pie, options::OPT_no_pie,
450                            ToolChain.isPIEDefault(Args));
451       if (IsPIE)
452         CmdArgs.push_back("-pie");
453       CmdArgs.push_back("-dynamic-linker");
454       CmdArgs.push_back(Args.MakeArgString(Twine(D.DyldPrefix) +
455                                            ToolChain.getDynamicLinker(Args)));
456     }
457   }
458 
459   CmdArgs.push_back("-o");
460   CmdArgs.push_back(Output.getFilename());
461 
462   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles,
463                    options::OPT_r)) {
464     if (!isAndroid && !IsIAMCU) {
465       const char *crt1 = nullptr;
466       if (!Args.hasArg(options::OPT_shared)) {
467         if (Args.hasArg(options::OPT_pg))
468           crt1 = "gcrt1.o";
469         else if (IsPIE)
470           crt1 = "Scrt1.o";
471         else if (IsStaticPIE)
472           crt1 = "rcrt1.o";
473         else
474           crt1 = "crt1.o";
475       }
476       if (crt1)
477         CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crt1)));
478 
479       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crti.o")));
480     }
481 
482     if (IsVE) {
483       CmdArgs.push_back("-z");
484       CmdArgs.push_back("max-page-size=0x4000000");
485     }
486 
487     if (IsIAMCU)
488       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt0.o")));
489     else if (HasCRTBeginEndFiles) {
490       std::string P;
491       if (ToolChain.GetRuntimeLibType(Args) == ToolChain::RLT_CompilerRT &&
492           !isAndroid) {
493         std::string crtbegin = ToolChain.getCompilerRT(Args, "crtbegin",
494                                                        ToolChain::FT_Object);
495         if (ToolChain.getVFS().exists(crtbegin))
496           P = crtbegin;
497       }
498       if (P.empty()) {
499         const char *crtbegin;
500         if (Args.hasArg(options::OPT_shared))
501           crtbegin = isAndroid ? "crtbegin_so.o" : "crtbeginS.o";
502         else if (IsStatic)
503           crtbegin = isAndroid ? "crtbegin_static.o" : "crtbeginT.o";
504         else if (IsPIE || IsStaticPIE)
505           crtbegin = isAndroid ? "crtbegin_dynamic.o" : "crtbeginS.o";
506         else
507           crtbegin = isAndroid ? "crtbegin_dynamic.o" : "crtbegin.o";
508         P = ToolChain.GetFilePath(crtbegin);
509       }
510       CmdArgs.push_back(Args.MakeArgString(P));
511     }
512 
513     // Add crtfastmath.o if available and fast math is enabled.
514     ToolChain.addFastMathRuntimeIfAvailable(Args, CmdArgs);
515 
516     if (isAndroid && Args.hasFlag(options::OPT_fandroid_pad_segment,
517                                   options::OPT_fno_android_pad_segment, false))
518       CmdArgs.push_back(
519           Args.MakeArgString(ToolChain.GetFilePath("crt_pad_segment.o")));
520   }
521 
522   Args.addAllArgs(CmdArgs, {options::OPT_L, options::OPT_u});
523 
524   ToolChain.AddFilePathLibArgs(Args, CmdArgs);
525 
526   if (D.isUsingLTO()) {
527     assert(!Inputs.empty() && "Must have at least one input.");
528     // Find the first filename InputInfo object.
529     auto Input = llvm::find_if(
530         Inputs, [](const InputInfo &II) -> bool { return II.isFilename(); });
531     if (Input == Inputs.end())
532       // For a very rare case, all of the inputs to the linker are
533       // InputArg. If that happens, just use the first InputInfo.
534       Input = Inputs.begin();
535 
536     addLTOOptions(ToolChain, Args, CmdArgs, Output, *Input,
537                   D.getLTOMode() == LTOK_Thin);
538   }
539 
540   if (Args.hasArg(options::OPT_Z_Xlinker__no_demangle))
541     CmdArgs.push_back("--no-demangle");
542 
543   bool NeedsSanitizerDeps = addSanitizerRuntimes(ToolChain, Args, CmdArgs);
544   bool NeedsXRayDeps = addXRayRuntime(ToolChain, Args, CmdArgs);
545   addLinkerCompressDebugSectionsOption(ToolChain, Args, CmdArgs);
546   AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
547 
548   addHIPRuntimeLibArgs(ToolChain, C, Args, CmdArgs);
549 
550   // The profile runtime also needs access to system libraries.
551   getToolChain().addProfileRTLibs(Args, CmdArgs);
552 
553   if (D.CCCIsCXX() &&
554       !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs,
555                    options::OPT_r)) {
556     if (ToolChain.ShouldLinkCXXStdlib(Args)) {
557       bool OnlyLibstdcxxStatic = Args.hasArg(options::OPT_static_libstdcxx) &&
558                                  !Args.hasArg(options::OPT_static);
559       if (OnlyLibstdcxxStatic)
560         CmdArgs.push_back("-Bstatic");
561       ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
562       if (OnlyLibstdcxxStatic)
563         CmdArgs.push_back("-Bdynamic");
564     }
565     CmdArgs.push_back("-lm");
566   }
567 
568   // Silence warnings when linking C code with a C++ '-stdlib' argument.
569   Args.ClaimAllArgs(options::OPT_stdlib_EQ);
570 
571   // Additional linker set-up and flags for Fortran. This is required in order
572   // to generate executables. As Fortran runtime depends on the C runtime,
573   // these dependencies need to be listed before the C runtime below (i.e.
574   // AddRunTimeLibs).
575   if (D.IsFlangMode()) {
576     addFortranRuntimeLibraryPath(ToolChain, Args, CmdArgs);
577     addFortranRuntimeLibs(ToolChain, Args, CmdArgs);
578     CmdArgs.push_back("-lm");
579   }
580 
581   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_r)) {
582     if (!Args.hasArg(options::OPT_nodefaultlibs)) {
583       if (IsStatic || IsStaticPIE)
584         CmdArgs.push_back("--start-group");
585 
586       if (NeedsSanitizerDeps)
587         linkSanitizerRuntimeDeps(ToolChain, Args, CmdArgs);
588 
589       if (NeedsXRayDeps)
590         linkXRayRuntimeDeps(ToolChain, Args, CmdArgs);
591 
592       bool WantPthread = Args.hasArg(options::OPT_pthread) ||
593                          Args.hasArg(options::OPT_pthreads);
594 
595       // Use the static OpenMP runtime with -static-openmp
596       bool StaticOpenMP = Args.hasArg(options::OPT_static_openmp) &&
597                           !Args.hasArg(options::OPT_static);
598 
599       // FIXME: Only pass GompNeedsRT = true for platforms with libgomp that
600       // require librt. Most modern Linux platforms do, but some may not.
601       if (addOpenMPRuntime(C, CmdArgs, ToolChain, Args, StaticOpenMP,
602                            JA.isHostOffloading(Action::OFK_OpenMP),
603                            /* GompNeedsRT= */ true))
604         // OpenMP runtimes implies pthreads when using the GNU toolchain.
605         // FIXME: Does this really make sense for all GNU toolchains?
606         WantPthread = true;
607 
608       AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
609 
610       // LLVM support for atomics on 32-bit SPARC V8+ is incomplete, so
611       // forcibly link with libatomic as a workaround.
612       // TODO: Issue #41880 and D118021.
613       if (getToolChain().getTriple().getArch() == llvm::Triple::sparc) {
614         CmdArgs.push_back("--push-state");
615         CmdArgs.push_back("--as-needed");
616         CmdArgs.push_back("-latomic");
617         CmdArgs.push_back("--pop-state");
618       }
619 
620       // We don't need libpthread neither for bionic (Android) nor for musl,
621       // (used by OHOS as runtime library).
622       if (WantPthread && !isAndroid && !isOHOSFamily)
623         CmdArgs.push_back("-lpthread");
624 
625       if (Args.hasArg(options::OPT_fsplit_stack))
626         CmdArgs.push_back("--wrap=pthread_create");
627 
628       if (!Args.hasArg(options::OPT_nolibc))
629         CmdArgs.push_back("-lc");
630 
631       // Add IAMCU specific libs, if needed.
632       if (IsIAMCU)
633         CmdArgs.push_back("-lgloss");
634 
635       if (IsStatic || IsStaticPIE)
636         CmdArgs.push_back("--end-group");
637       else
638         AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
639 
640       // Add IAMCU specific libs (outside the group), if needed.
641       if (IsIAMCU) {
642         CmdArgs.push_back("--as-needed");
643         CmdArgs.push_back("-lsoftfp");
644         CmdArgs.push_back("--no-as-needed");
645       }
646     }
647 
648     if (!Args.hasArg(options::OPT_nostartfiles) && !IsIAMCU) {
649       if (HasCRTBeginEndFiles) {
650         std::string P;
651         if (ToolChain.GetRuntimeLibType(Args) == ToolChain::RLT_CompilerRT &&
652             !isAndroid) {
653           std::string crtend = ToolChain.getCompilerRT(Args, "crtend",
654                                                        ToolChain::FT_Object);
655           if (ToolChain.getVFS().exists(crtend))
656             P = crtend;
657         }
658         if (P.empty()) {
659           const char *crtend;
660           if (Args.hasArg(options::OPT_shared))
661             crtend = isAndroid ? "crtend_so.o" : "crtendS.o";
662           else if (IsPIE || IsStaticPIE)
663             crtend = isAndroid ? "crtend_android.o" : "crtendS.o";
664           else
665             crtend = isAndroid ? "crtend_android.o" : "crtend.o";
666           P = ToolChain.GetFilePath(crtend);
667         }
668         CmdArgs.push_back(Args.MakeArgString(P));
669       }
670       if (!isAndroid)
671         CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
672     }
673   }
674 
675   Args.AddAllArgs(CmdArgs, options::OPT_T);
676 
677   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
678   C.addCommand(std::make_unique<Command>(JA, *this,
679                                          ResponseFileSupport::AtFileCurCP(),
680                                          Exec, CmdArgs, Inputs, Output));
681 }
682 
683 void tools::gnutools::Assembler::ConstructJob(Compilation &C,
684                                               const JobAction &JA,
685                                               const InputInfo &Output,
686                                               const InputInfoList &Inputs,
687                                               const ArgList &Args,
688                                               const char *LinkingOutput) const {
689   const auto &D = getToolChain().getDriver();
690 
691   claimNoWarnArgs(Args);
692 
693   ArgStringList CmdArgs;
694 
695   llvm::Reloc::Model RelocationModel;
696   unsigned PICLevel;
697   bool IsPIE;
698   const char *DefaultAssembler = "as";
699   // Enforce GNU as on Solaris; the native assembler's input syntax isn't fully
700   // compatible.
701   if (getToolChain().getTriple().isOSSolaris())
702     DefaultAssembler = "gas";
703   std::tie(RelocationModel, PICLevel, IsPIE) =
704       ParsePICArgs(getToolChain(), Args);
705 
706   if (const Arg *A = Args.getLastArg(options::OPT_gz, options::OPT_gz_EQ)) {
707     if (A->getOption().getID() == options::OPT_gz) {
708       CmdArgs.push_back("--compress-debug-sections");
709     } else {
710       StringRef Value = A->getValue();
711       if (Value == "none" || Value == "zlib" || Value == "zstd") {
712         CmdArgs.push_back(
713             Args.MakeArgString("--compress-debug-sections=" + Twine(Value)));
714       } else {
715         D.Diag(diag::err_drv_unsupported_option_argument)
716             << A->getSpelling() << Value;
717       }
718     }
719   }
720 
721   switch (getToolChain().getArch()) {
722   default:
723     break;
724   // Add --32/--64 to make sure we get the format we want.
725   // This is incomplete
726   case llvm::Triple::x86:
727     CmdArgs.push_back("--32");
728     break;
729   case llvm::Triple::x86_64:
730     if (getToolChain().getTriple().isX32())
731       CmdArgs.push_back("--x32");
732     else
733       CmdArgs.push_back("--64");
734     break;
735   case llvm::Triple::ppc: {
736     CmdArgs.push_back("-a32");
737     CmdArgs.push_back("-mppc");
738     CmdArgs.push_back("-mbig-endian");
739     CmdArgs.push_back(ppc::getPPCAsmModeForCPU(
740         getCPUName(D, Args, getToolChain().getTriple())));
741     break;
742   }
743   case llvm::Triple::ppcle: {
744     CmdArgs.push_back("-a32");
745     CmdArgs.push_back("-mppc");
746     CmdArgs.push_back("-mlittle-endian");
747     CmdArgs.push_back(ppc::getPPCAsmModeForCPU(
748         getCPUName(D, Args, getToolChain().getTriple())));
749     break;
750   }
751   case llvm::Triple::ppc64: {
752     CmdArgs.push_back("-a64");
753     CmdArgs.push_back("-mppc64");
754     CmdArgs.push_back("-mbig-endian");
755     CmdArgs.push_back(ppc::getPPCAsmModeForCPU(
756         getCPUName(D, Args, getToolChain().getTriple())));
757     break;
758   }
759   case llvm::Triple::ppc64le: {
760     CmdArgs.push_back("-a64");
761     CmdArgs.push_back("-mppc64");
762     CmdArgs.push_back("-mlittle-endian");
763     CmdArgs.push_back(ppc::getPPCAsmModeForCPU(
764         getCPUName(D, Args, getToolChain().getTriple())));
765     break;
766   }
767   case llvm::Triple::riscv32:
768   case llvm::Triple::riscv64: {
769     StringRef ABIName = riscv::getRISCVABI(Args, getToolChain().getTriple());
770     CmdArgs.push_back("-mabi");
771     CmdArgs.push_back(ABIName.data());
772     std::string MArchName =
773         riscv::getRISCVArch(Args, getToolChain().getTriple());
774     CmdArgs.push_back("-march");
775     CmdArgs.push_back(Args.MakeArgString(MArchName));
776     if (!Args.hasFlag(options::OPT_mrelax, options::OPT_mno_relax, true))
777       Args.addOptOutFlag(CmdArgs, options::OPT_mrelax, options::OPT_mno_relax);
778     break;
779   }
780   case llvm::Triple::sparc:
781   case llvm::Triple::sparcel: {
782     CmdArgs.push_back("-32");
783     std::string CPU = getCPUName(D, Args, getToolChain().getTriple());
784     CmdArgs.push_back(
785         sparc::getSparcAsmModeForCPU(CPU, getToolChain().getTriple()));
786     AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
787     break;
788   }
789   case llvm::Triple::sparcv9: {
790     CmdArgs.push_back("-64");
791     std::string CPU = getCPUName(D, Args, getToolChain().getTriple());
792     CmdArgs.push_back(
793         sparc::getSparcAsmModeForCPU(CPU, getToolChain().getTriple()));
794     AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
795     break;
796   }
797   case llvm::Triple::arm:
798   case llvm::Triple::armeb:
799   case llvm::Triple::thumb:
800   case llvm::Triple::thumbeb: {
801     const llvm::Triple &Triple2 = getToolChain().getTriple();
802     CmdArgs.push_back(arm::isARMBigEndian(Triple2, Args) ? "-EB" : "-EL");
803     switch (Triple2.getSubArch()) {
804     case llvm::Triple::ARMSubArch_v7:
805       CmdArgs.push_back("-mfpu=neon");
806       break;
807     case llvm::Triple::ARMSubArch_v8:
808       CmdArgs.push_back("-mfpu=crypto-neon-fp-armv8");
809       break;
810     default:
811       break;
812     }
813 
814     switch (arm::getARMFloatABI(getToolChain(), Args)) {
815     case arm::FloatABI::Invalid: llvm_unreachable("must have an ABI!");
816     case arm::FloatABI::Soft:
817       CmdArgs.push_back(Args.MakeArgString("-mfloat-abi=soft"));
818       break;
819     case arm::FloatABI::SoftFP:
820       CmdArgs.push_back(Args.MakeArgString("-mfloat-abi=softfp"));
821       break;
822     case arm::FloatABI::Hard:
823       CmdArgs.push_back(Args.MakeArgString("-mfloat-abi=hard"));
824       break;
825     }
826 
827     Args.AddLastArg(CmdArgs, options::OPT_march_EQ);
828     normalizeCPUNamesForAssembler(Args, CmdArgs);
829 
830     Args.AddLastArg(CmdArgs, options::OPT_mfpu_EQ);
831     // The integrated assembler doesn't implement e_flags setting behavior for
832     // -meabi=gnu (gcc -mabi={apcs-gnu,atpcs} passes -meabi=gnu to gas). For
833     // compatibility we accept but warn.
834     if (Arg *A = Args.getLastArgNoClaim(options::OPT_mabi_EQ))
835       A->ignoreTargetSpecific();
836     break;
837   }
838   case llvm::Triple::aarch64:
839   case llvm::Triple::aarch64_be: {
840     CmdArgs.push_back(
841         getToolChain().getArch() == llvm::Triple::aarch64_be ? "-EB" : "-EL");
842     Args.AddLastArg(CmdArgs, options::OPT_march_EQ);
843     normalizeCPUNamesForAssembler(Args, CmdArgs);
844 
845     break;
846   }
847   // TODO: handle loongarch32.
848   case llvm::Triple::loongarch64: {
849     StringRef ABIName =
850         loongarch::getLoongArchABI(D, Args, getToolChain().getTriple());
851     CmdArgs.push_back(Args.MakeArgString("-mabi=" + ABIName));
852     break;
853   }
854   case llvm::Triple::mips:
855   case llvm::Triple::mipsel:
856   case llvm::Triple::mips64:
857   case llvm::Triple::mips64el: {
858     StringRef CPUName;
859     StringRef ABIName;
860     mips::getMipsCPUAndABI(Args, getToolChain().getTriple(), CPUName, ABIName);
861     ABIName = mips::getGnuCompatibleMipsABIName(ABIName);
862 
863     CmdArgs.push_back("-march");
864     CmdArgs.push_back(CPUName.data());
865 
866     CmdArgs.push_back("-mabi");
867     CmdArgs.push_back(ABIName.data());
868 
869     // -mno-shared should be emitted unless -fpic, -fpie, -fPIC, -fPIE,
870     // or -mshared (not implemented) is in effect.
871     if (RelocationModel == llvm::Reloc::Static)
872       CmdArgs.push_back("-mno-shared");
873 
874     // LLVM doesn't support -mplt yet and acts as if it is always given.
875     // However, -mplt has no effect with the N64 ABI.
876     if (ABIName != "64" && !Args.hasArg(options::OPT_mno_abicalls))
877       CmdArgs.push_back("-call_nonpic");
878 
879     if (getToolChain().getTriple().isLittleEndian())
880       CmdArgs.push_back("-EL");
881     else
882       CmdArgs.push_back("-EB");
883 
884     if (Arg *A = Args.getLastArg(options::OPT_mnan_EQ)) {
885       if (StringRef(A->getValue()) == "2008")
886         CmdArgs.push_back(Args.MakeArgString("-mnan=2008"));
887     }
888 
889     // Add the last -mfp32/-mfpxx/-mfp64 or -mfpxx if it is enabled by default.
890     if (Arg *A = Args.getLastArg(options::OPT_mfp32, options::OPT_mfpxx,
891                                  options::OPT_mfp64)) {
892       A->claim();
893       A->render(Args, CmdArgs);
894     } else if (mips::shouldUseFPXX(
895                    Args, getToolChain().getTriple(), CPUName, ABIName,
896                    mips::getMipsFloatABI(getToolChain().getDriver(), Args,
897                                          getToolChain().getTriple())))
898       CmdArgs.push_back("-mfpxx");
899 
900     // Pass on -mmips16 or -mno-mips16. However, the assembler equivalent of
901     // -mno-mips16 is actually -no-mips16.
902     if (Arg *A =
903             Args.getLastArg(options::OPT_mips16, options::OPT_mno_mips16)) {
904       if (A->getOption().matches(options::OPT_mips16)) {
905         A->claim();
906         A->render(Args, CmdArgs);
907       } else {
908         A->claim();
909         CmdArgs.push_back("-no-mips16");
910       }
911     }
912 
913     Args.AddLastArg(CmdArgs, options::OPT_mmicromips,
914                     options::OPT_mno_micromips);
915     Args.AddLastArg(CmdArgs, options::OPT_mdsp, options::OPT_mno_dsp);
916     Args.AddLastArg(CmdArgs, options::OPT_mdspr2, options::OPT_mno_dspr2);
917 
918     if (Arg *A = Args.getLastArg(options::OPT_mmsa, options::OPT_mno_msa)) {
919       // Do not use AddLastArg because not all versions of MIPS assembler
920       // support -mmsa / -mno-msa options.
921       if (A->getOption().matches(options::OPT_mmsa))
922         CmdArgs.push_back(Args.MakeArgString("-mmsa"));
923     }
924 
925     Args.AddLastArg(CmdArgs, options::OPT_mhard_float,
926                     options::OPT_msoft_float);
927 
928     Args.AddLastArg(CmdArgs, options::OPT_mdouble_float,
929                     options::OPT_msingle_float);
930 
931     Args.AddLastArg(CmdArgs, options::OPT_modd_spreg,
932                     options::OPT_mno_odd_spreg);
933 
934     AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
935     break;
936   }
937   case llvm::Triple::systemz: {
938     // Always pass an -march option, since our default of z10 is later
939     // than the GNU assembler's default.
940     std::string CPUName = systemz::getSystemZTargetCPU(Args);
941     CmdArgs.push_back(Args.MakeArgString("-march=" + CPUName));
942     break;
943   }
944   case llvm::Triple::ve:
945     DefaultAssembler = "nas";
946   }
947 
948   for (const Arg *A : Args.filtered(options::OPT_ffile_prefix_map_EQ,
949                                     options::OPT_fdebug_prefix_map_EQ)) {
950     StringRef Map = A->getValue();
951     if (!Map.contains('='))
952       D.Diag(diag::err_drv_invalid_argument_to_option)
953           << Map << A->getOption().getName();
954     else {
955       CmdArgs.push_back(Args.MakeArgString("--debug-prefix-map"));
956       CmdArgs.push_back(Args.MakeArgString(Map));
957     }
958     A->claim();
959   }
960 
961   Args.AddAllArgs(CmdArgs, options::OPT_I);
962   Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
963 
964   CmdArgs.push_back("-o");
965   CmdArgs.push_back(Output.getFilename());
966 
967   for (const auto &II : Inputs)
968     CmdArgs.push_back(II.getFilename());
969 
970   if (Arg *A = Args.getLastArg(options::OPT_g_Flag, options::OPT_gN_Group,
971                                options::OPT_gdwarf_2, options::OPT_gdwarf_3,
972                                options::OPT_gdwarf_4, options::OPT_gdwarf_5,
973                                options::OPT_gdwarf))
974     if (!A->getOption().matches(options::OPT_g0)) {
975       Args.AddLastArg(CmdArgs, options::OPT_g_Flag);
976 
977       unsigned DwarfVersion = getDwarfVersion(getToolChain(), Args);
978       CmdArgs.push_back(Args.MakeArgString("-gdwarf-" + Twine(DwarfVersion)));
979     }
980 
981   const char *Exec =
982       Args.MakeArgString(getToolChain().GetProgramPath(DefaultAssembler));
983   C.addCommand(std::make_unique<Command>(JA, *this,
984                                          ResponseFileSupport::AtFileCurCP(),
985                                          Exec, CmdArgs, Inputs, Output));
986 
987   // Handle the debug info splitting at object creation time if we're
988   // creating an object.
989   // TODO: Currently only works on linux with newer objcopy.
990   if (Args.hasArg(options::OPT_gsplit_dwarf) &&
991       getToolChain().getTriple().isOSLinux())
992     SplitDebugInfo(getToolChain(), C, *this, JA, Args, Output,
993                    SplitDebugName(JA, Args, Inputs[0], Output));
994 }
995 
996 namespace {
997 // Filter to remove Multilibs that don't exist as a suffix to Path
998 class FilterNonExistent {
999   StringRef Base, File;
1000   llvm::vfs::FileSystem &VFS;
1001 
1002 public:
1003   FilterNonExistent(StringRef Base, StringRef File, llvm::vfs::FileSystem &VFS)
1004       : Base(Base), File(File), VFS(VFS) {}
1005   bool operator()(const Multilib &M) {
1006     return !VFS.exists(Base + M.gccSuffix() + File);
1007   }
1008 };
1009 } // end anonymous namespace
1010 
1011 static bool isSoftFloatABI(const ArgList &Args) {
1012   Arg *A = Args.getLastArg(options::OPT_msoft_float, options::OPT_mhard_float,
1013                            options::OPT_mfloat_abi_EQ);
1014   if (!A)
1015     return false;
1016 
1017   return A->getOption().matches(options::OPT_msoft_float) ||
1018          (A->getOption().matches(options::OPT_mfloat_abi_EQ) &&
1019           A->getValue() == StringRef("soft"));
1020 }
1021 
1022 static bool isArmOrThumbArch(llvm::Triple::ArchType Arch) {
1023   return Arch == llvm::Triple::arm || Arch == llvm::Triple::thumb;
1024 }
1025 
1026 static bool isMipsEL(llvm::Triple::ArchType Arch) {
1027   return Arch == llvm::Triple::mipsel || Arch == llvm::Triple::mips64el;
1028 }
1029 
1030 static bool isMips16(const ArgList &Args) {
1031   Arg *A = Args.getLastArg(options::OPT_mips16, options::OPT_mno_mips16);
1032   return A && A->getOption().matches(options::OPT_mips16);
1033 }
1034 
1035 static bool isMicroMips(const ArgList &Args) {
1036   Arg *A = Args.getLastArg(options::OPT_mmicromips, options::OPT_mno_micromips);
1037   return A && A->getOption().matches(options::OPT_mmicromips);
1038 }
1039 
1040 static bool isMSP430(llvm::Triple::ArchType Arch) {
1041   return Arch == llvm::Triple::msp430;
1042 }
1043 
1044 static bool findMipsCsMultilibs(const Multilib::flags_list &Flags,
1045                                 FilterNonExistent &NonExistent,
1046                                 DetectedMultilibs &Result) {
1047   // Check for Code Sourcery toolchain multilibs
1048   MultilibSet CSMipsMultilibs;
1049   {
1050     auto MArchMips16 = MultilibBuilder("/mips16").flag("-m32").flag("-mips16");
1051 
1052     auto MArchMicroMips =
1053         MultilibBuilder("/micromips").flag("-m32").flag("-mmicromips");
1054 
1055     auto MArchDefault = MultilibBuilder("")
1056                             .flag("-mips16", /*Disallow=*/true)
1057                             .flag("-mmicromips", /*Disallow=*/true);
1058 
1059     auto UCLibc = MultilibBuilder("/uclibc").flag("-muclibc");
1060 
1061     auto SoftFloat = MultilibBuilder("/soft-float").flag("-msoft-float");
1062 
1063     auto Nan2008 = MultilibBuilder("/nan2008").flag("-mnan=2008");
1064 
1065     auto DefaultFloat = MultilibBuilder("")
1066                             .flag("-msoft-float", /*Disallow=*/true)
1067                             .flag("-mnan=2008", /*Disallow=*/true);
1068 
1069     auto BigEndian =
1070         MultilibBuilder("").flag("-EB").flag("-EL", /*Disallow=*/true);
1071 
1072     auto LittleEndian =
1073         MultilibBuilder("/el").flag("-EL").flag("-EB", /*Disallow=*/true);
1074 
1075     // Note that this one's osSuffix is ""
1076     auto MAbi64 = MultilibBuilder("")
1077                       .gccSuffix("/64")
1078                       .includeSuffix("/64")
1079                       .flag("-mabi=n64")
1080                       .flag("-mabi=n32", /*Disallow=*/true)
1081                       .flag("-m32", /*Disallow=*/true);
1082 
1083     CSMipsMultilibs =
1084         MultilibSetBuilder()
1085             .Either(MArchMips16, MArchMicroMips, MArchDefault)
1086             .Maybe(UCLibc)
1087             .Either(SoftFloat, Nan2008, DefaultFloat)
1088             .FilterOut("/micromips/nan2008")
1089             .FilterOut("/mips16/nan2008")
1090             .Either(BigEndian, LittleEndian)
1091             .Maybe(MAbi64)
1092             .FilterOut("/mips16.*/64")
1093             .FilterOut("/micromips.*/64")
1094             .makeMultilibSet()
1095             .FilterOut(NonExistent)
1096             .setIncludeDirsCallback([](const Multilib &M) {
1097               std::vector<std::string> Dirs({"/include"});
1098               if (StringRef(M.includeSuffix()).starts_with("/uclibc"))
1099                 Dirs.push_back(
1100                     "/../../../../mips-linux-gnu/libc/uclibc/usr/include");
1101               else
1102                 Dirs.push_back("/../../../../mips-linux-gnu/libc/usr/include");
1103               return Dirs;
1104             });
1105   }
1106 
1107   MultilibSet DebianMipsMultilibs;
1108   {
1109     MultilibBuilder MAbiN32 =
1110         MultilibBuilder().gccSuffix("/n32").includeSuffix("/n32").flag(
1111             "-mabi=n32");
1112 
1113     MultilibBuilder M64 = MultilibBuilder()
1114                               .gccSuffix("/64")
1115                               .includeSuffix("/64")
1116                               .flag("-m64")
1117                               .flag("-m32", /*Disallow=*/true)
1118                               .flag("-mabi=n32", /*Disallow=*/true);
1119 
1120     MultilibBuilder M32 = MultilibBuilder()
1121                               .gccSuffix("/32")
1122                               .flag("-m64", /*Disallow=*/true)
1123                               .flag("-m32")
1124                               .flag("-mabi=n32", /*Disallow=*/true);
1125 
1126     DebianMipsMultilibs = MultilibSetBuilder()
1127                               .Either(M32, M64, MAbiN32)
1128                               .makeMultilibSet()
1129                               .FilterOut(NonExistent);
1130   }
1131 
1132   // Sort candidates. Toolchain that best meets the directories tree goes first.
1133   // Then select the first toolchains matches command line flags.
1134   MultilibSet *Candidates[] = {&CSMipsMultilibs, &DebianMipsMultilibs};
1135   if (CSMipsMultilibs.size() < DebianMipsMultilibs.size())
1136     std::iter_swap(Candidates, Candidates + 1);
1137   for (const MultilibSet *Candidate : Candidates) {
1138     if (Candidate->select(Flags, Result.SelectedMultilibs)) {
1139       if (Candidate == &DebianMipsMultilibs)
1140         Result.BiarchSibling = Multilib();
1141       Result.Multilibs = *Candidate;
1142       return true;
1143     }
1144   }
1145   return false;
1146 }
1147 
1148 static bool findMipsAndroidMultilibs(llvm::vfs::FileSystem &VFS, StringRef Path,
1149                                      const Multilib::flags_list &Flags,
1150                                      FilterNonExistent &NonExistent,
1151                                      DetectedMultilibs &Result) {
1152 
1153   MultilibSet AndroidMipsMultilibs =
1154       MultilibSetBuilder()
1155           .Maybe(MultilibBuilder("/mips-r2", {}, {}).flag("-march=mips32r2"))
1156           .Maybe(MultilibBuilder("/mips-r6", {}, {}).flag("-march=mips32r6"))
1157           .makeMultilibSet()
1158           .FilterOut(NonExistent);
1159 
1160   MultilibSet AndroidMipselMultilibs =
1161       MultilibSetBuilder()
1162           .Either(MultilibBuilder().flag("-march=mips32"),
1163                   MultilibBuilder("/mips-r2", "", "/mips-r2")
1164                       .flag("-march=mips32r2"),
1165                   MultilibBuilder("/mips-r6", "", "/mips-r6")
1166                       .flag("-march=mips32r6"))
1167           .makeMultilibSet()
1168           .FilterOut(NonExistent);
1169 
1170   MultilibSet AndroidMips64elMultilibs =
1171       MultilibSetBuilder()
1172           .Either(MultilibBuilder().flag("-march=mips64r6"),
1173                   MultilibBuilder("/32/mips-r1", "", "/mips-r1")
1174                       .flag("-march=mips32"),
1175                   MultilibBuilder("/32/mips-r2", "", "/mips-r2")
1176                       .flag("-march=mips32r2"),
1177                   MultilibBuilder("/32/mips-r6", "", "/mips-r6")
1178                       .flag("-march=mips32r6"))
1179           .makeMultilibSet()
1180           .FilterOut(NonExistent);
1181 
1182   MultilibSet *MS = &AndroidMipsMultilibs;
1183   if (VFS.exists(Path + "/mips-r6"))
1184     MS = &AndroidMipselMultilibs;
1185   else if (VFS.exists(Path + "/32"))
1186     MS = &AndroidMips64elMultilibs;
1187   if (MS->select(Flags, Result.SelectedMultilibs)) {
1188     Result.Multilibs = *MS;
1189     return true;
1190   }
1191   return false;
1192 }
1193 
1194 static bool findMipsMuslMultilibs(const Multilib::flags_list &Flags,
1195                                   FilterNonExistent &NonExistent,
1196                                   DetectedMultilibs &Result) {
1197   // Musl toolchain multilibs
1198   MultilibSet MuslMipsMultilibs;
1199   {
1200     auto MArchMipsR2 = MultilibBuilder("")
1201                            .osSuffix("/mips-r2-hard-musl")
1202                            .flag("-EB")
1203                            .flag("-EL", /*Disallow=*/true)
1204                            .flag("-march=mips32r2");
1205 
1206     auto MArchMipselR2 = MultilibBuilder("/mipsel-r2-hard-musl")
1207                              .flag("-EB", /*Disallow=*/true)
1208                              .flag("-EL")
1209                              .flag("-march=mips32r2");
1210 
1211     MuslMipsMultilibs = MultilibSetBuilder()
1212                             .Either(MArchMipsR2, MArchMipselR2)
1213                             .makeMultilibSet();
1214 
1215     // Specify the callback that computes the include directories.
1216     MuslMipsMultilibs.setIncludeDirsCallback([](const Multilib &M) {
1217       return std::vector<std::string>(
1218           {"/../sysroot" + M.osSuffix() + "/usr/include"});
1219     });
1220   }
1221   if (MuslMipsMultilibs.select(Flags, Result.SelectedMultilibs)) {
1222     Result.Multilibs = MuslMipsMultilibs;
1223     return true;
1224   }
1225   return false;
1226 }
1227 
1228 static bool findMipsMtiMultilibs(const Multilib::flags_list &Flags,
1229                                  FilterNonExistent &NonExistent,
1230                                  DetectedMultilibs &Result) {
1231   // CodeScape MTI toolchain v1.2 and early.
1232   MultilibSet MtiMipsMultilibsV1;
1233   {
1234     auto MArchMips32 = MultilibBuilder("/mips32")
1235                            .flag("-m32")
1236                            .flag("-m64", /*Disallow=*/true)
1237                            .flag("-mmicromips", /*Disallow=*/true)
1238                            .flag("-march=mips32");
1239 
1240     auto MArchMicroMips = MultilibBuilder("/micromips")
1241                               .flag("-m32")
1242                               .flag("-m64", /*Disallow=*/true)
1243                               .flag("-mmicromips");
1244 
1245     auto MArchMips64r2 = MultilibBuilder("/mips64r2")
1246                              .flag("-m32", /*Disallow=*/true)
1247                              .flag("-m64")
1248                              .flag("-march=mips64r2");
1249 
1250     auto MArchMips64 = MultilibBuilder("/mips64")
1251                            .flag("-m32", /*Disallow=*/true)
1252                            .flag("-m64")
1253                            .flag("-march=mips64r2", /*Disallow=*/true);
1254 
1255     auto MArchDefault = MultilibBuilder("")
1256                             .flag("-m32")
1257                             .flag("-m64", /*Disallow=*/true)
1258                             .flag("-mmicromips", /*Disallow=*/true)
1259                             .flag("-march=mips32r2");
1260 
1261     auto Mips16 = MultilibBuilder("/mips16").flag("-mips16");
1262 
1263     auto UCLibc = MultilibBuilder("/uclibc").flag("-muclibc");
1264 
1265     auto MAbi64 = MultilibBuilder("/64")
1266                       .flag("-mabi=n64")
1267                       .flag("-mabi=n32", /*Disallow=*/true)
1268                       .flag("-m32", /*Disallow=*/true);
1269 
1270     auto BigEndian =
1271         MultilibBuilder("").flag("-EB").flag("-EL", /*Disallow=*/true);
1272 
1273     auto LittleEndian =
1274         MultilibBuilder("/el").flag("-EL").flag("-EB", /*Disallow=*/true);
1275 
1276     auto SoftFloat = MultilibBuilder("/sof").flag("-msoft-float");
1277 
1278     auto Nan2008 = MultilibBuilder("/nan2008").flag("-mnan=2008");
1279 
1280     MtiMipsMultilibsV1 =
1281         MultilibSetBuilder()
1282             .Either(MArchMips32, MArchMicroMips, MArchMips64r2, MArchMips64,
1283                     MArchDefault)
1284             .Maybe(UCLibc)
1285             .Maybe(Mips16)
1286             .FilterOut("/mips64/mips16")
1287             .FilterOut("/mips64r2/mips16")
1288             .FilterOut("/micromips/mips16")
1289             .Maybe(MAbi64)
1290             .FilterOut("/micromips/64")
1291             .FilterOut("/mips32/64")
1292             .FilterOut("^/64")
1293             .FilterOut("/mips16/64")
1294             .Either(BigEndian, LittleEndian)
1295             .Maybe(SoftFloat)
1296             .Maybe(Nan2008)
1297             .FilterOut(".*sof/nan2008")
1298             .makeMultilibSet()
1299             .FilterOut(NonExistent)
1300             .setIncludeDirsCallback([](const Multilib &M) {
1301               std::vector<std::string> Dirs({"/include"});
1302               if (StringRef(M.includeSuffix()).starts_with("/uclibc"))
1303                 Dirs.push_back("/../../../../sysroot/uclibc/usr/include");
1304               else
1305                 Dirs.push_back("/../../../../sysroot/usr/include");
1306               return Dirs;
1307             });
1308   }
1309 
1310   // CodeScape IMG toolchain starting from v1.3.
1311   MultilibSet MtiMipsMultilibsV2;
1312   {
1313     auto BeHard = MultilibBuilder("/mips-r2-hard")
1314                       .flag("-EB")
1315                       .flag("-msoft-float", /*Disallow=*/true)
1316                       .flag("-mnan=2008", /*Disallow=*/true)
1317                       .flag("-muclibc", /*Disallow=*/true);
1318     auto BeSoft = MultilibBuilder("/mips-r2-soft")
1319                       .flag("-EB")
1320                       .flag("-msoft-float")
1321                       .flag("-mnan=2008", /*Disallow=*/true);
1322     auto ElHard = MultilibBuilder("/mipsel-r2-hard")
1323                       .flag("-EL")
1324                       .flag("-msoft-float", /*Disallow=*/true)
1325                       .flag("-mnan=2008", /*Disallow=*/true)
1326                       .flag("-muclibc", /*Disallow=*/true);
1327     auto ElSoft = MultilibBuilder("/mipsel-r2-soft")
1328                       .flag("-EL")
1329                       .flag("-msoft-float")
1330                       .flag("-mnan=2008", /*Disallow=*/true)
1331                       .flag("-mmicromips", /*Disallow=*/true);
1332     auto BeHardNan = MultilibBuilder("/mips-r2-hard-nan2008")
1333                          .flag("-EB")
1334                          .flag("-msoft-float", /*Disallow=*/true)
1335                          .flag("-mnan=2008")
1336                          .flag("-muclibc", /*Disallow=*/true);
1337     auto ElHardNan = MultilibBuilder("/mipsel-r2-hard-nan2008")
1338                          .flag("-EL")
1339                          .flag("-msoft-float", /*Disallow=*/true)
1340                          .flag("-mnan=2008")
1341                          .flag("-muclibc", /*Disallow=*/true)
1342                          .flag("-mmicromips", /*Disallow=*/true);
1343     auto BeHardNanUclibc = MultilibBuilder("/mips-r2-hard-nan2008-uclibc")
1344                                .flag("-EB")
1345                                .flag("-msoft-float", /*Disallow=*/true)
1346                                .flag("-mnan=2008")
1347                                .flag("-muclibc");
1348     auto ElHardNanUclibc = MultilibBuilder("/mipsel-r2-hard-nan2008-uclibc")
1349                                .flag("-EL")
1350                                .flag("-msoft-float", /*Disallow=*/true)
1351                                .flag("-mnan=2008")
1352                                .flag("-muclibc");
1353     auto BeHardUclibc = MultilibBuilder("/mips-r2-hard-uclibc")
1354                             .flag("-EB")
1355                             .flag("-msoft-float", /*Disallow=*/true)
1356                             .flag("-mnan=2008", /*Disallow=*/true)
1357                             .flag("-muclibc");
1358     auto ElHardUclibc = MultilibBuilder("/mipsel-r2-hard-uclibc")
1359                             .flag("-EL")
1360                             .flag("-msoft-float", /*Disallow=*/true)
1361                             .flag("-mnan=2008", /*Disallow=*/true)
1362                             .flag("-muclibc");
1363     auto ElMicroHardNan = MultilibBuilder("/micromipsel-r2-hard-nan2008")
1364                               .flag("-EL")
1365                               .flag("-msoft-float", /*Disallow=*/true)
1366                               .flag("-mnan=2008")
1367                               .flag("-mmicromips");
1368     auto ElMicroSoft = MultilibBuilder("/micromipsel-r2-soft")
1369                            .flag("-EL")
1370                            .flag("-msoft-float")
1371                            .flag("-mnan=2008", /*Disallow=*/true)
1372                            .flag("-mmicromips");
1373 
1374     auto O32 = MultilibBuilder("/lib")
1375                    .osSuffix("")
1376                    .flag("-mabi=n32", /*Disallow=*/true)
1377                    .flag("-mabi=n64", /*Disallow=*/true);
1378     auto N32 = MultilibBuilder("/lib32")
1379                    .osSuffix("")
1380                    .flag("-mabi=n32")
1381                    .flag("-mabi=n64", /*Disallow=*/true);
1382     auto N64 = MultilibBuilder("/lib64")
1383                    .osSuffix("")
1384                    .flag("-mabi=n32", /*Disallow=*/true)
1385                    .flag("-mabi=n64");
1386 
1387     MtiMipsMultilibsV2 =
1388         MultilibSetBuilder()
1389             .Either({BeHard, BeSoft, ElHard, ElSoft, BeHardNan, ElHardNan,
1390                      BeHardNanUclibc, ElHardNanUclibc, BeHardUclibc,
1391                      ElHardUclibc, ElMicroHardNan, ElMicroSoft})
1392             .Either(O32, N32, N64)
1393             .makeMultilibSet()
1394             .FilterOut(NonExistent)
1395             .setIncludeDirsCallback([](const Multilib &M) {
1396               return std::vector<std::string>({"/../../../../sysroot" +
1397                                                M.includeSuffix() +
1398                                                "/../usr/include"});
1399             })
1400             .setFilePathsCallback([](const Multilib &M) {
1401               return std::vector<std::string>(
1402                   {"/../../../../mips-mti-linux-gnu/lib" + M.gccSuffix()});
1403             });
1404   }
1405   for (auto *Candidate : {&MtiMipsMultilibsV1, &MtiMipsMultilibsV2}) {
1406     if (Candidate->select(Flags, Result.SelectedMultilibs)) {
1407       Result.Multilibs = *Candidate;
1408       return true;
1409     }
1410   }
1411   return false;
1412 }
1413 
1414 static bool findMipsImgMultilibs(const Multilib::flags_list &Flags,
1415                                  FilterNonExistent &NonExistent,
1416                                  DetectedMultilibs &Result) {
1417   // CodeScape IMG toolchain v1.2 and early.
1418   MultilibSet ImgMultilibsV1;
1419   {
1420     auto Mips64r6 = MultilibBuilder("/mips64r6")
1421                         .flag("-m64")
1422                         .flag("-m32", /*Disallow=*/true);
1423 
1424     auto LittleEndian =
1425         MultilibBuilder("/el").flag("-EL").flag("-EB", /*Disallow=*/true);
1426 
1427     auto MAbi64 = MultilibBuilder("/64")
1428                       .flag("-mabi=n64")
1429                       .flag("-mabi=n32", /*Disallow=*/true)
1430                       .flag("-m32", /*Disallow=*/true);
1431 
1432     ImgMultilibsV1 =
1433         MultilibSetBuilder()
1434             .Maybe(Mips64r6)
1435             .Maybe(MAbi64)
1436             .Maybe(LittleEndian)
1437             .makeMultilibSet()
1438             .FilterOut(NonExistent)
1439             .setIncludeDirsCallback([](const Multilib &M) {
1440               return std::vector<std::string>(
1441                   {"/include", "/../../../../sysroot/usr/include"});
1442             });
1443   }
1444 
1445   // CodeScape IMG toolchain starting from v1.3.
1446   MultilibSet ImgMultilibsV2;
1447   {
1448     auto BeHard = MultilibBuilder("/mips-r6-hard")
1449                       .flag("-EB")
1450                       .flag("-msoft-float", /*Disallow=*/true)
1451                       .flag("-mmicromips", /*Disallow=*/true);
1452     auto BeSoft = MultilibBuilder("/mips-r6-soft")
1453                       .flag("-EB")
1454                       .flag("-msoft-float")
1455                       .flag("-mmicromips", /*Disallow=*/true);
1456     auto ElHard = MultilibBuilder("/mipsel-r6-hard")
1457                       .flag("-EL")
1458                       .flag("-msoft-float", /*Disallow=*/true)
1459                       .flag("-mmicromips", /*Disallow=*/true);
1460     auto ElSoft = MultilibBuilder("/mipsel-r6-soft")
1461                       .flag("-EL")
1462                       .flag("-msoft-float")
1463                       .flag("-mmicromips", /*Disallow=*/true);
1464     auto BeMicroHard = MultilibBuilder("/micromips-r6-hard")
1465                            .flag("-EB")
1466                            .flag("-msoft-float", /*Disallow=*/true)
1467                            .flag("-mmicromips");
1468     auto BeMicroSoft = MultilibBuilder("/micromips-r6-soft")
1469                            .flag("-EB")
1470                            .flag("-msoft-float")
1471                            .flag("-mmicromips");
1472     auto ElMicroHard = MultilibBuilder("/micromipsel-r6-hard")
1473                            .flag("-EL")
1474                            .flag("-msoft-float", /*Disallow=*/true)
1475                            .flag("-mmicromips");
1476     auto ElMicroSoft = MultilibBuilder("/micromipsel-r6-soft")
1477                            .flag("-EL")
1478                            .flag("-msoft-float")
1479                            .flag("-mmicromips");
1480 
1481     auto O32 = MultilibBuilder("/lib")
1482                    .osSuffix("")
1483                    .flag("-mabi=n32", /*Disallow=*/true)
1484                    .flag("-mabi=n64", /*Disallow=*/true);
1485     auto N32 = MultilibBuilder("/lib32")
1486                    .osSuffix("")
1487                    .flag("-mabi=n32")
1488                    .flag("-mabi=n64", /*Disallow=*/true);
1489     auto N64 = MultilibBuilder("/lib64")
1490                    .osSuffix("")
1491                    .flag("-mabi=n32", /*Disallow=*/true)
1492                    .flag("-mabi=n64");
1493 
1494     ImgMultilibsV2 =
1495         MultilibSetBuilder()
1496             .Either({BeHard, BeSoft, ElHard, ElSoft, BeMicroHard, BeMicroSoft,
1497                      ElMicroHard, ElMicroSoft})
1498             .Either(O32, N32, N64)
1499             .makeMultilibSet()
1500             .FilterOut(NonExistent)
1501             .setIncludeDirsCallback([](const Multilib &M) {
1502               return std::vector<std::string>({"/../../../../sysroot" +
1503                                                M.includeSuffix() +
1504                                                "/../usr/include"});
1505             })
1506             .setFilePathsCallback([](const Multilib &M) {
1507               return std::vector<std::string>(
1508                   {"/../../../../mips-img-linux-gnu/lib" + M.gccSuffix()});
1509             });
1510   }
1511   for (auto *Candidate : {&ImgMultilibsV1, &ImgMultilibsV2}) {
1512     if (Candidate->select(Flags, Result.SelectedMultilibs)) {
1513       Result.Multilibs = *Candidate;
1514       return true;
1515     }
1516   }
1517   return false;
1518 }
1519 
1520 bool clang::driver::findMIPSMultilibs(const Driver &D,
1521                                       const llvm::Triple &TargetTriple,
1522                                       StringRef Path, const ArgList &Args,
1523                                       DetectedMultilibs &Result) {
1524   FilterNonExistent NonExistent(Path, "/crtbegin.o", D.getVFS());
1525 
1526   StringRef CPUName;
1527   StringRef ABIName;
1528   tools::mips::getMipsCPUAndABI(Args, TargetTriple, CPUName, ABIName);
1529 
1530   llvm::Triple::ArchType TargetArch = TargetTriple.getArch();
1531 
1532   Multilib::flags_list Flags;
1533   addMultilibFlag(TargetTriple.isMIPS32(), "-m32", Flags);
1534   addMultilibFlag(TargetTriple.isMIPS64(), "-m64", Flags);
1535   addMultilibFlag(isMips16(Args), "-mips16", Flags);
1536   addMultilibFlag(CPUName == "mips32", "-march=mips32", Flags);
1537   addMultilibFlag(CPUName == "mips32r2" || CPUName == "mips32r3" ||
1538                       CPUName == "mips32r5" || CPUName == "p5600",
1539                   "-march=mips32r2", Flags);
1540   addMultilibFlag(CPUName == "mips32r6", "-march=mips32r6", Flags);
1541   addMultilibFlag(CPUName == "mips64", "-march=mips64", Flags);
1542   addMultilibFlag(CPUName == "mips64r2" || CPUName == "mips64r3" ||
1543                       CPUName == "mips64r5" || CPUName == "octeon" ||
1544                       CPUName == "octeon+",
1545                   "-march=mips64r2", Flags);
1546   addMultilibFlag(CPUName == "mips64r6", "-march=mips64r6", Flags);
1547   addMultilibFlag(isMicroMips(Args), "-mmicromips", Flags);
1548   addMultilibFlag(tools::mips::isUCLibc(Args), "-muclibc", Flags);
1549   addMultilibFlag(tools::mips::isNaN2008(D, Args, TargetTriple), "-mnan=2008",
1550                   Flags);
1551   addMultilibFlag(ABIName == "n32", "-mabi=n32", Flags);
1552   addMultilibFlag(ABIName == "n64", "-mabi=n64", Flags);
1553   addMultilibFlag(isSoftFloatABI(Args), "-msoft-float", Flags);
1554   addMultilibFlag(!isSoftFloatABI(Args), "-mhard-float", Flags);
1555   addMultilibFlag(isMipsEL(TargetArch), "-EL", Flags);
1556   addMultilibFlag(!isMipsEL(TargetArch), "-EB", Flags);
1557 
1558   if (TargetTriple.isAndroid())
1559     return findMipsAndroidMultilibs(D.getVFS(), Path, Flags, NonExistent,
1560                                     Result);
1561 
1562   if (TargetTriple.getVendor() == llvm::Triple::MipsTechnologies &&
1563       TargetTriple.getOS() == llvm::Triple::Linux &&
1564       TargetTriple.getEnvironment() == llvm::Triple::UnknownEnvironment)
1565     return findMipsMuslMultilibs(Flags, NonExistent, Result);
1566 
1567   if (TargetTriple.getVendor() == llvm::Triple::MipsTechnologies &&
1568       TargetTriple.getOS() == llvm::Triple::Linux &&
1569       TargetTriple.isGNUEnvironment())
1570     return findMipsMtiMultilibs(Flags, NonExistent, Result);
1571 
1572   if (TargetTriple.getVendor() == llvm::Triple::ImaginationTechnologies &&
1573       TargetTriple.getOS() == llvm::Triple::Linux &&
1574       TargetTriple.isGNUEnvironment())
1575     return findMipsImgMultilibs(Flags, NonExistent, Result);
1576 
1577   if (findMipsCsMultilibs(Flags, NonExistent, Result))
1578     return true;
1579 
1580   // Fallback to the regular toolchain-tree structure.
1581   Multilib Default;
1582   Result.Multilibs.push_back(Default);
1583   Result.Multilibs.FilterOut(NonExistent);
1584 
1585   if (Result.Multilibs.select(Flags, Result.SelectedMultilibs)) {
1586     Result.BiarchSibling = Multilib();
1587     return true;
1588   }
1589 
1590   return false;
1591 }
1592 
1593 static void findAndroidArmMultilibs(const Driver &D,
1594                                     const llvm::Triple &TargetTriple,
1595                                     StringRef Path, const ArgList &Args,
1596                                     DetectedMultilibs &Result) {
1597   // Find multilibs with subdirectories like armv7-a, thumb, armv7-a/thumb.
1598   FilterNonExistent NonExistent(Path, "/crtbegin.o", D.getVFS());
1599   MultilibBuilder ArmV7Multilib = MultilibBuilder("/armv7-a")
1600                                       .flag("-march=armv7-a")
1601                                       .flag("-mthumb", /*Disallow=*/true);
1602   MultilibBuilder ThumbMultilib = MultilibBuilder("/thumb")
1603                                       .flag("-march=armv7-a", /*Disallow=*/true)
1604                                       .flag("-mthumb");
1605   MultilibBuilder ArmV7ThumbMultilib =
1606       MultilibBuilder("/armv7-a/thumb").flag("-march=armv7-a").flag("-mthumb");
1607   MultilibBuilder DefaultMultilib =
1608       MultilibBuilder("")
1609           .flag("-march=armv7-a", /*Disallow=*/true)
1610           .flag("-mthumb", /*Disallow=*/true);
1611   MultilibSet AndroidArmMultilibs =
1612       MultilibSetBuilder()
1613           .Either(ThumbMultilib, ArmV7Multilib, ArmV7ThumbMultilib,
1614                   DefaultMultilib)
1615           .makeMultilibSet()
1616           .FilterOut(NonExistent);
1617 
1618   Multilib::flags_list Flags;
1619   llvm::StringRef Arch = Args.getLastArgValue(options::OPT_march_EQ);
1620   bool IsArmArch = TargetTriple.getArch() == llvm::Triple::arm;
1621   bool IsThumbArch = TargetTriple.getArch() == llvm::Triple::thumb;
1622   bool IsV7SubArch = TargetTriple.getSubArch() == llvm::Triple::ARMSubArch_v7;
1623   bool IsThumbMode = IsThumbArch ||
1624       Args.hasFlag(options::OPT_mthumb, options::OPT_mno_thumb, false) ||
1625       (IsArmArch && llvm::ARM::parseArchISA(Arch) == llvm::ARM::ISAKind::THUMB);
1626   bool IsArmV7Mode = (IsArmArch || IsThumbArch) &&
1627       (llvm::ARM::parseArchVersion(Arch) == 7 ||
1628        (IsArmArch && Arch == "" && IsV7SubArch));
1629   addMultilibFlag(IsArmV7Mode, "-march=armv7-a", Flags);
1630   addMultilibFlag(IsThumbMode, "-mthumb", Flags);
1631 
1632   if (AndroidArmMultilibs.select(Flags, Result.SelectedMultilibs))
1633     Result.Multilibs = AndroidArmMultilibs;
1634 }
1635 
1636 static bool findMSP430Multilibs(const Driver &D,
1637                                 const llvm::Triple &TargetTriple,
1638                                 StringRef Path, const ArgList &Args,
1639                                 DetectedMultilibs &Result) {
1640   FilterNonExistent NonExistent(Path, "/crtbegin.o", D.getVFS());
1641   MultilibBuilder WithoutExceptions =
1642       MultilibBuilder("/430").flag("-exceptions", /*Disallow=*/true);
1643   MultilibBuilder WithExceptions =
1644       MultilibBuilder("/430/exceptions").flag("-exceptions");
1645 
1646   // FIXME: when clang starts to support msp430x ISA additional logic
1647   // to select between multilib must be implemented
1648   // MultilibBuilder MSP430xMultilib = MultilibBuilder("/large");
1649 
1650   Result.Multilibs.push_back(WithoutExceptions.makeMultilib());
1651   Result.Multilibs.push_back(WithExceptions.makeMultilib());
1652   Result.Multilibs.FilterOut(NonExistent);
1653 
1654   Multilib::flags_list Flags;
1655   addMultilibFlag(Args.hasFlag(options::OPT_fexceptions,
1656                                options::OPT_fno_exceptions, false),
1657                   "-exceptions", Flags);
1658   if (Result.Multilibs.select(Flags, Result.SelectedMultilibs))
1659     return true;
1660 
1661   return false;
1662 }
1663 
1664 static void findCSKYMultilibs(const Driver &D, const llvm::Triple &TargetTriple,
1665                               StringRef Path, const ArgList &Args,
1666                               DetectedMultilibs &Result) {
1667   FilterNonExistent NonExistent(Path, "/crtbegin.o", D.getVFS());
1668 
1669   tools::csky::FloatABI TheFloatABI = tools::csky::getCSKYFloatABI(D, Args);
1670   std::optional<llvm::StringRef> Res =
1671       tools::csky::getCSKYArchName(D, Args, TargetTriple);
1672 
1673   if (!Res)
1674     return;
1675   auto ARCHName = *Res;
1676 
1677   Multilib::flags_list Flags;
1678   addMultilibFlag(TheFloatABI == tools::csky::FloatABI::Hard, "-hard-fp",
1679                   Flags);
1680   addMultilibFlag(TheFloatABI == tools::csky::FloatABI::SoftFP, "-soft-fp",
1681                   Flags);
1682   addMultilibFlag(TheFloatABI == tools::csky::FloatABI::Soft, "-soft", Flags);
1683   addMultilibFlag(ARCHName == "ck801", "-march=ck801", Flags);
1684   addMultilibFlag(ARCHName == "ck802", "-march=ck802", Flags);
1685   addMultilibFlag(ARCHName == "ck803", "-march=ck803", Flags);
1686   addMultilibFlag(ARCHName == "ck804", "-march=ck804", Flags);
1687   addMultilibFlag(ARCHName == "ck805", "-march=ck805", Flags);
1688   addMultilibFlag(ARCHName == "ck807", "-march=ck807", Flags);
1689   addMultilibFlag(ARCHName == "ck810", "-march=ck810", Flags);
1690   addMultilibFlag(ARCHName == "ck810v", "-march=ck810v", Flags);
1691   addMultilibFlag(ARCHName == "ck860", "-march=ck860", Flags);
1692   addMultilibFlag(ARCHName == "ck860v", "-march=ck860v", Flags);
1693 
1694   bool isBigEndian = false;
1695   if (Arg *A = Args.getLastArg(options::OPT_mlittle_endian,
1696                                options::OPT_mbig_endian))
1697     isBigEndian = !A->getOption().matches(options::OPT_mlittle_endian);
1698   addMultilibFlag(isBigEndian, "-EB", Flags);
1699 
1700   auto HardFloat = MultilibBuilder("/hard-fp").flag("-hard-fp");
1701   auto SoftFpFloat = MultilibBuilder("/soft-fp").flag("-soft-fp");
1702   auto SoftFloat = MultilibBuilder("").flag("-soft");
1703   auto Arch801 = MultilibBuilder("/ck801").flag("-march=ck801");
1704   auto Arch802 = MultilibBuilder("/ck802").flag("-march=ck802");
1705   auto Arch803 = MultilibBuilder("/ck803").flag("-march=ck803");
1706   // CK804 use the same library as CK803
1707   auto Arch804 = MultilibBuilder("/ck803").flag("-march=ck804");
1708   auto Arch805 = MultilibBuilder("/ck805").flag("-march=ck805");
1709   auto Arch807 = MultilibBuilder("/ck807").flag("-march=ck807");
1710   auto Arch810 = MultilibBuilder("").flag("-march=ck810");
1711   auto Arch810v = MultilibBuilder("/ck810v").flag("-march=ck810v");
1712   auto Arch860 = MultilibBuilder("/ck860").flag("-march=ck860");
1713   auto Arch860v = MultilibBuilder("/ck860v").flag("-march=ck860v");
1714   auto BigEndian = MultilibBuilder("/big").flag("-EB");
1715 
1716   MultilibSet CSKYMultilibs =
1717       MultilibSetBuilder()
1718           .Maybe(BigEndian)
1719           .Either({Arch801, Arch802, Arch803, Arch804, Arch805, Arch807,
1720                    Arch810, Arch810v, Arch860, Arch860v})
1721           .Either(HardFloat, SoftFpFloat, SoftFloat)
1722           .makeMultilibSet()
1723           .FilterOut(NonExistent);
1724 
1725   if (CSKYMultilibs.select(Flags, Result.SelectedMultilibs))
1726     Result.Multilibs = CSKYMultilibs;
1727 }
1728 
1729 /// Extend the multi-lib re-use selection mechanism for RISC-V.
1730 /// This function will try to re-use multi-lib if they are compatible.
1731 /// Definition of compatible:
1732 ///   - ABI must be the same.
1733 ///   - multi-lib is a subset of current arch, e.g. multi-lib=march=rv32im
1734 ///     is a subset of march=rv32imc.
1735 ///   - march that contains atomic extension can't reuse multi-lib that
1736 ///     doesn't have atomic, vice versa. e.g. multi-lib=march=rv32im and
1737 ///     march=rv32ima are not compatible, because software and hardware
1738 ///     atomic operation can't work together correctly.
1739 static bool
1740 selectRISCVMultilib(const MultilibSet &RISCVMultilibSet, StringRef Arch,
1741                     const Multilib::flags_list &Flags,
1742                     llvm::SmallVectorImpl<Multilib> &SelectedMultilibs) {
1743   // Try to find the perfect matching multi-lib first.
1744   if (RISCVMultilibSet.select(Flags, SelectedMultilibs))
1745     return true;
1746 
1747   Multilib::flags_list NewFlags;
1748   std::vector<MultilibBuilder> NewMultilibs;
1749 
1750   llvm::Expected<std::unique_ptr<llvm::RISCVISAInfo>> ParseResult =
1751       llvm::RISCVISAInfo::parseArchString(
1752           Arch, /*EnableExperimentalExtension=*/true,
1753           /*ExperimentalExtensionVersionCheck=*/false);
1754   // Ignore any error here, we assume it will be handled in another place.
1755   if (llvm::errorToBool(ParseResult.takeError()))
1756     return false;
1757 
1758   auto &ISAInfo = *ParseResult;
1759 
1760   addMultilibFlag(ISAInfo->getXLen() == 32, "-m32", NewFlags);
1761   addMultilibFlag(ISAInfo->getXLen() == 64, "-m64", NewFlags);
1762 
1763   // Collect all flags except march=*
1764   for (StringRef Flag : Flags) {
1765     if (Flag.starts_with("!march=") || Flag.starts_with("-march="))
1766       continue;
1767 
1768     NewFlags.push_back(Flag.str());
1769   }
1770 
1771   llvm::StringSet<> AllArchExts;
1772   // Reconstruct multi-lib list, and break march option into separated
1773   // extension. e.g. march=rv32im -> +i +m
1774   for (const auto &M : RISCVMultilibSet) {
1775     bool Skip = false;
1776 
1777     MultilibBuilder NewMultilib =
1778         MultilibBuilder(M.gccSuffix(), M.osSuffix(), M.includeSuffix());
1779     for (StringRef Flag : M.flags()) {
1780       // Add back all flags except -march.
1781       if (!Flag.consume_front("-march=")) {
1782         NewMultilib.flag(Flag);
1783         continue;
1784       }
1785 
1786       // Break down -march into individual extension.
1787       llvm::Expected<std::unique_ptr<llvm::RISCVISAInfo>> MLConfigParseResult =
1788           llvm::RISCVISAInfo::parseArchString(
1789               Flag, /*EnableExperimentalExtension=*/true,
1790               /*ExperimentalExtensionVersionCheck=*/false);
1791       // Ignore any error here, we assume it will handled in another place.
1792       if (llvm::errorToBool(MLConfigParseResult.takeError())) {
1793         // We might get a parsing error if rv32e in the list, we could just skip
1794         // that and process the rest of multi-lib configs.
1795         Skip = true;
1796         continue;
1797       }
1798       auto &MLConfigISAInfo = *MLConfigParseResult;
1799 
1800       for (auto &MLConfigArchExt : MLConfigISAInfo->getExtensions()) {
1801         auto ExtName = MLConfigArchExt.first;
1802         NewMultilib.flag(Twine("-", ExtName).str());
1803 
1804         if (AllArchExts.insert(ExtName).second) {
1805           addMultilibFlag(ISAInfo->hasExtension(ExtName),
1806                           Twine("-", ExtName).str(), NewFlags);
1807         }
1808       }
1809 
1810       // Check the XLEN explicitly.
1811       if (MLConfigISAInfo->getXLen() == 32) {
1812         NewMultilib.flag("-m32");
1813         NewMultilib.flag("-m64", /*Disallow*/ true);
1814       } else {
1815         NewMultilib.flag("-m32", /*Disallow*/ true);
1816         NewMultilib.flag("-m64");
1817       }
1818 
1819       // Atomic extension must be explicitly checked, soft and hard atomic
1820       // operation never co-work correctly.
1821       if (!MLConfigISAInfo->hasExtension("a"))
1822         NewMultilib.flag("-a", /*Disallow*/ true);
1823     }
1824 
1825     if (Skip)
1826       continue;
1827 
1828     NewMultilibs.emplace_back(NewMultilib);
1829   }
1830 
1831   // Build an internal used only multi-lib list, used for checking any
1832   // compatible multi-lib.
1833   MultilibSet NewRISCVMultilibs =
1834       MultilibSetBuilder().Either(NewMultilibs).makeMultilibSet();
1835 
1836   if (NewRISCVMultilibs.select(NewFlags, SelectedMultilibs))
1837     for (const Multilib &NewSelectedM : SelectedMultilibs)
1838       for (const auto &M : RISCVMultilibSet)
1839         // Look up the corresponding multi-lib entry in original multi-lib set.
1840         if (M.gccSuffix() == NewSelectedM.gccSuffix())
1841           return true;
1842 
1843   return false;
1844 }
1845 
1846 static void findRISCVBareMetalMultilibs(const Driver &D,
1847                                         const llvm::Triple &TargetTriple,
1848                                         StringRef Path, const ArgList &Args,
1849                                         DetectedMultilibs &Result) {
1850   FilterNonExistent NonExistent(Path, "/crtbegin.o", D.getVFS());
1851   struct RiscvMultilib {
1852     StringRef march;
1853     StringRef mabi;
1854   };
1855   // currently only support the set of multilibs like riscv-gnu-toolchain does.
1856   // TODO: support MULTILIB_REUSE
1857   constexpr RiscvMultilib RISCVMultilibSet[] = {
1858       {"rv32i", "ilp32"},     {"rv32im", "ilp32"},     {"rv32iac", "ilp32"},
1859       {"rv32imac", "ilp32"},  {"rv32imafc", "ilp32f"}, {"rv64imac", "lp64"},
1860       {"rv64imafdc", "lp64d"}};
1861 
1862   std::vector<MultilibBuilder> Ms;
1863   for (auto Element : RISCVMultilibSet) {
1864     // multilib path rule is ${march}/${mabi}
1865     Ms.emplace_back(
1866         MultilibBuilder(
1867             (Twine(Element.march) + "/" + Twine(Element.mabi)).str())
1868             .flag(Twine("-march=", Element.march).str())
1869             .flag(Twine("-mabi=", Element.mabi).str()));
1870   }
1871   MultilibSet RISCVMultilibs =
1872       MultilibSetBuilder()
1873           .Either(Ms)
1874           .makeMultilibSet()
1875           .FilterOut(NonExistent)
1876           .setFilePathsCallback([](const Multilib &M) {
1877             return std::vector<std::string>(
1878                 {M.gccSuffix(),
1879                  "/../../../../riscv64-unknown-elf/lib" + M.gccSuffix(),
1880                  "/../../../../riscv32-unknown-elf/lib" + M.gccSuffix()});
1881           });
1882 
1883   Multilib::flags_list Flags;
1884   llvm::StringSet<> Added_ABIs;
1885   StringRef ABIName = tools::riscv::getRISCVABI(Args, TargetTriple);
1886   std::string MArch = tools::riscv::getRISCVArch(Args, TargetTriple);
1887   for (auto Element : RISCVMultilibSet) {
1888     addMultilibFlag(MArch == Element.march,
1889                     Twine("-march=", Element.march).str().c_str(), Flags);
1890     if (!Added_ABIs.count(Element.mabi)) {
1891       Added_ABIs.insert(Element.mabi);
1892       addMultilibFlag(ABIName == Element.mabi,
1893                       Twine("-mabi=", Element.mabi).str().c_str(), Flags);
1894     }
1895   }
1896 
1897   if (selectRISCVMultilib(RISCVMultilibs, MArch, Flags,
1898                           Result.SelectedMultilibs))
1899     Result.Multilibs = RISCVMultilibs;
1900 }
1901 
1902 static void findRISCVMultilibs(const Driver &D,
1903                                const llvm::Triple &TargetTriple, StringRef Path,
1904                                const ArgList &Args, DetectedMultilibs &Result) {
1905   if (TargetTriple.getOS() == llvm::Triple::UnknownOS)
1906     return findRISCVBareMetalMultilibs(D, TargetTriple, Path, Args, Result);
1907 
1908   FilterNonExistent NonExistent(Path, "/crtbegin.o", D.getVFS());
1909   MultilibBuilder Ilp32 =
1910       MultilibBuilder("lib32/ilp32").flag("-m32").flag("-mabi=ilp32");
1911   MultilibBuilder Ilp32f =
1912       MultilibBuilder("lib32/ilp32f").flag("-m32").flag("-mabi=ilp32f");
1913   MultilibBuilder Ilp32d =
1914       MultilibBuilder("lib32/ilp32d").flag("-m32").flag("-mabi=ilp32d");
1915   MultilibBuilder Lp64 =
1916       MultilibBuilder("lib64/lp64").flag("-m64").flag("-mabi=lp64");
1917   MultilibBuilder Lp64f =
1918       MultilibBuilder("lib64/lp64f").flag("-m64").flag("-mabi=lp64f");
1919   MultilibBuilder Lp64d =
1920       MultilibBuilder("lib64/lp64d").flag("-m64").flag("-mabi=lp64d");
1921   MultilibSet RISCVMultilibs =
1922       MultilibSetBuilder()
1923           .Either({Ilp32, Ilp32f, Ilp32d, Lp64, Lp64f, Lp64d})
1924           .makeMultilibSet()
1925           .FilterOut(NonExistent);
1926 
1927   Multilib::flags_list Flags;
1928   bool IsRV64 = TargetTriple.getArch() == llvm::Triple::riscv64;
1929   StringRef ABIName = tools::riscv::getRISCVABI(Args, TargetTriple);
1930 
1931   addMultilibFlag(!IsRV64, "-m32", Flags);
1932   addMultilibFlag(IsRV64, "-m64", Flags);
1933   addMultilibFlag(ABIName == "ilp32", "-mabi=ilp32", Flags);
1934   addMultilibFlag(ABIName == "ilp32f", "-mabi=ilp32f", Flags);
1935   addMultilibFlag(ABIName == "ilp32d", "-mabi=ilp32d", Flags);
1936   addMultilibFlag(ABIName == "lp64", "-mabi=lp64", Flags);
1937   addMultilibFlag(ABIName == "lp64f", "-mabi=lp64f", Flags);
1938   addMultilibFlag(ABIName == "lp64d", "-mabi=lp64d", Flags);
1939 
1940   if (RISCVMultilibs.select(Flags, Result.SelectedMultilibs))
1941     Result.Multilibs = RISCVMultilibs;
1942 }
1943 
1944 static bool findBiarchMultilibs(const Driver &D,
1945                                 const llvm::Triple &TargetTriple,
1946                                 StringRef Path, const ArgList &Args,
1947                                 bool NeedsBiarchSuffix,
1948                                 DetectedMultilibs &Result) {
1949   MultilibBuilder DefaultBuilder;
1950 
1951   // Some versions of SUSE and Fedora on ppc64 put 32-bit libs
1952   // in what would normally be GCCInstallPath and put the 64-bit
1953   // libs in a subdirectory named 64. The simple logic we follow is that
1954   // *if* there is a subdirectory of the right name with crtbegin.o in it,
1955   // we use that. If not, and if not a biarch triple alias, we look for
1956   // crtbegin.o without the subdirectory.
1957 
1958   StringRef Suff64 = "/64";
1959   // Solaris uses platform-specific suffixes instead of /64.
1960   if (TargetTriple.isOSSolaris()) {
1961     switch (TargetTriple.getArch()) {
1962     case llvm::Triple::x86:
1963     case llvm::Triple::x86_64:
1964       Suff64 = "/amd64";
1965       break;
1966     case llvm::Triple::sparc:
1967     case llvm::Triple::sparcv9:
1968       Suff64 = "/sparcv9";
1969       break;
1970     default:
1971       break;
1972     }
1973   }
1974 
1975   Multilib Alt64 = MultilibBuilder()
1976                        .gccSuffix(Suff64)
1977                        .includeSuffix(Suff64)
1978                        .flag("-m32", /*Disallow=*/true)
1979                        .flag("-m64")
1980                        .flag("-mx32", /*Disallow=*/true)
1981                        .makeMultilib();
1982   Multilib Alt32 = MultilibBuilder()
1983                        .gccSuffix("/32")
1984                        .includeSuffix("/32")
1985                        .flag("-m32")
1986                        .flag("-m64", /*Disallow=*/true)
1987                        .flag("-mx32", /*Disallow=*/true)
1988                        .makeMultilib();
1989   Multilib Altx32 = MultilibBuilder()
1990                         .gccSuffix("/x32")
1991                         .includeSuffix("/x32")
1992                         .flag("-m32", /*Disallow=*/true)
1993                         .flag("-m64", /*Disallow=*/true)
1994                         .flag("-mx32")
1995                         .makeMultilib();
1996   Multilib Alt32sparc = MultilibBuilder()
1997                             .gccSuffix("/sparcv8plus")
1998                             .includeSuffix("/sparcv8plus")
1999                             .flag("-m32")
2000                             .flag("-m64", /*Disallow=*/true)
2001                             .makeMultilib();
2002 
2003   // GCC toolchain for IAMCU doesn't have crtbegin.o, so look for libgcc.a.
2004   FilterNonExistent NonExistent(
2005       Path, TargetTriple.isOSIAMCU() ? "/libgcc.a" : "/crtbegin.o", D.getVFS());
2006 
2007   // Determine default multilib from: 32, 64, x32
2008   // Also handle cases such as 64 on 32, 32 on 64, etc.
2009   enum { UNKNOWN, WANT32, WANT64, WANTX32 } Want = UNKNOWN;
2010   const bool IsX32 = TargetTriple.isX32();
2011   if (TargetTriple.isArch32Bit() && !NonExistent(Alt32))
2012     Want = WANT64;
2013   if (TargetTriple.isArch32Bit() && !NonExistent(Alt32sparc))
2014     Want = WANT64;
2015   else if (TargetTriple.isArch64Bit() && IsX32 && !NonExistent(Altx32))
2016     Want = WANT64;
2017   else if (TargetTriple.isArch64Bit() && !IsX32 && !NonExistent(Alt64))
2018     Want = WANT32;
2019   else if (TargetTriple.isArch64Bit() && !NonExistent(Alt32sparc))
2020     Want = WANT64;
2021   else {
2022     if (TargetTriple.isArch32Bit())
2023       Want = NeedsBiarchSuffix ? WANT64 : WANT32;
2024     else if (IsX32)
2025       Want = NeedsBiarchSuffix ? WANT64 : WANTX32;
2026     else
2027       Want = NeedsBiarchSuffix ? WANT32 : WANT64;
2028   }
2029 
2030   if (Want == WANT32)
2031     DefaultBuilder.flag("-m32")
2032         .flag("-m64", /*Disallow=*/true)
2033         .flag("-mx32", /*Disallow=*/true);
2034   else if (Want == WANT64)
2035     DefaultBuilder.flag("-m32", /*Disallow=*/true)
2036         .flag("-m64")
2037         .flag("-mx32", /*Disallow=*/true);
2038   else if (Want == WANTX32)
2039     DefaultBuilder.flag("-m32", /*Disallow=*/true)
2040         .flag("-m64", /*Disallow=*/true)
2041         .flag("-mx32");
2042   else
2043     return false;
2044 
2045   Multilib Default = DefaultBuilder.makeMultilib();
2046 
2047   Result.Multilibs.push_back(Default);
2048   Result.Multilibs.push_back(Alt64);
2049   Result.Multilibs.push_back(Alt32);
2050   Result.Multilibs.push_back(Altx32);
2051   Result.Multilibs.push_back(Alt32sparc);
2052 
2053   Result.Multilibs.FilterOut(NonExistent);
2054 
2055   Multilib::flags_list Flags;
2056   addMultilibFlag(TargetTriple.isArch64Bit() && !IsX32, "-m64", Flags);
2057   addMultilibFlag(TargetTriple.isArch32Bit(), "-m32", Flags);
2058   addMultilibFlag(TargetTriple.isArch64Bit() && IsX32, "-mx32", Flags);
2059 
2060   if (!Result.Multilibs.select(Flags, Result.SelectedMultilibs))
2061     return false;
2062 
2063   if (Result.SelectedMultilibs.back() == Alt64 ||
2064       Result.SelectedMultilibs.back() == Alt32 ||
2065       Result.SelectedMultilibs.back() == Altx32 ||
2066       Result.SelectedMultilibs.back() == Alt32sparc)
2067     Result.BiarchSibling = Default;
2068 
2069   return true;
2070 }
2071 
2072 /// Generic_GCC - A tool chain using the 'gcc' command to perform
2073 /// all subcommands; this relies on gcc translating the majority of
2074 /// command line options.
2075 
2076 /// Less-than for GCCVersion, implementing a Strict Weak Ordering.
2077 bool Generic_GCC::GCCVersion::isOlderThan(int RHSMajor, int RHSMinor,
2078                                           int RHSPatch,
2079                                           StringRef RHSPatchSuffix) const {
2080   if (Major != RHSMajor)
2081     return Major < RHSMajor;
2082   if (Minor != RHSMinor) {
2083     // Note that versions without a specified minor sort higher than those with
2084     // a minor.
2085     if (RHSMinor == -1)
2086       return true;
2087     if (Minor == -1)
2088       return false;
2089     return Minor < RHSMinor;
2090   }
2091   if (Patch != RHSPatch) {
2092     // Note that versions without a specified patch sort higher than those with
2093     // a patch.
2094     if (RHSPatch == -1)
2095       return true;
2096     if (Patch == -1)
2097       return false;
2098 
2099     // Otherwise just sort on the patch itself.
2100     return Patch < RHSPatch;
2101   }
2102   if (PatchSuffix != RHSPatchSuffix) {
2103     // Sort empty suffixes higher.
2104     if (RHSPatchSuffix.empty())
2105       return true;
2106     if (PatchSuffix.empty())
2107       return false;
2108 
2109     // Provide a lexicographic sort to make this a total ordering.
2110     return PatchSuffix < RHSPatchSuffix;
2111   }
2112 
2113   // The versions are equal.
2114   return false;
2115 }
2116 
2117 /// Parse a GCCVersion object out of a string of text.
2118 ///
2119 /// This is the primary means of forming GCCVersion objects.
2120 /*static*/
2121 Generic_GCC::GCCVersion Generic_GCC::GCCVersion::Parse(StringRef VersionText) {
2122   const GCCVersion BadVersion = {VersionText.str(), -1, -1, -1, "", "", ""};
2123   std::pair<StringRef, StringRef> First = VersionText.split('.');
2124   std::pair<StringRef, StringRef> Second = First.second.split('.');
2125 
2126   StringRef MajorStr = First.first;
2127   StringRef MinorStr = Second.first;
2128   StringRef PatchStr = Second.second;
2129 
2130   GCCVersion GoodVersion = {VersionText.str(), -1, -1, -1, "", "", ""};
2131 
2132   // Parse version number strings such as:
2133   //   5
2134   //   4.4
2135   //   4.4-patched
2136   //   4.4.0
2137   //   4.4.x
2138   //   4.4.2-rc4
2139   //   4.4.x-patched
2140   //   10-win32
2141   // Split on '.', handle 1, 2 or 3 such segments. Each segment must contain
2142   // purely a number, except for the last one, where a non-number suffix
2143   // is stored in PatchSuffix. The third segment is allowed to not contain
2144   // a number at all.
2145 
2146   auto TryParseLastNumber = [&](StringRef Segment, int &Number,
2147                                 std::string &OutStr) -> bool {
2148     // Look for a number prefix and parse that, and split out any trailing
2149     // string into GoodVersion.PatchSuffix.
2150 
2151     if (size_t EndNumber = Segment.find_first_not_of("0123456789")) {
2152       StringRef NumberStr = Segment.slice(0, EndNumber);
2153       if (NumberStr.getAsInteger(10, Number) || Number < 0)
2154         return false;
2155       OutStr = NumberStr;
2156       GoodVersion.PatchSuffix = Segment.substr(EndNumber);
2157       return true;
2158     }
2159     return false;
2160   };
2161   auto TryParseNumber = [](StringRef Segment, int &Number) -> bool {
2162     if (Segment.getAsInteger(10, Number) || Number < 0)
2163       return false;
2164     return true;
2165   };
2166 
2167   if (MinorStr.empty()) {
2168     // If no minor string, major is the last segment
2169     if (!TryParseLastNumber(MajorStr, GoodVersion.Major, GoodVersion.MajorStr))
2170       return BadVersion;
2171     return GoodVersion;
2172   }
2173 
2174   if (!TryParseNumber(MajorStr, GoodVersion.Major))
2175     return BadVersion;
2176   GoodVersion.MajorStr = MajorStr;
2177 
2178   if (PatchStr.empty()) {
2179     // If no patch string, minor is the last segment
2180     if (!TryParseLastNumber(MinorStr, GoodVersion.Minor, GoodVersion.MinorStr))
2181       return BadVersion;
2182     return GoodVersion;
2183   }
2184 
2185   if (!TryParseNumber(MinorStr, GoodVersion.Minor))
2186     return BadVersion;
2187   GoodVersion.MinorStr = MinorStr;
2188 
2189   // For the last segment, tolerate a missing number.
2190   std::string DummyStr;
2191   TryParseLastNumber(PatchStr, GoodVersion.Patch, DummyStr);
2192   return GoodVersion;
2193 }
2194 
2195 static llvm::StringRef getGCCToolchainDir(const ArgList &Args,
2196                                           llvm::StringRef SysRoot) {
2197   const Arg *A = Args.getLastArg(clang::driver::options::OPT_gcc_toolchain);
2198   if (A)
2199     return A->getValue();
2200 
2201   // If we have a SysRoot, ignore GCC_INSTALL_PREFIX.
2202   // GCC_INSTALL_PREFIX specifies the gcc installation for the default
2203   // sysroot and is likely not valid with a different sysroot.
2204   if (!SysRoot.empty())
2205     return "";
2206 
2207   return GCC_INSTALL_PREFIX;
2208 }
2209 
2210 /// Initialize a GCCInstallationDetector from the driver.
2211 ///
2212 /// This performs all of the autodetection and sets up the various paths.
2213 /// Once constructed, a GCCInstallationDetector is essentially immutable.
2214 ///
2215 /// FIXME: We shouldn't need an explicit TargetTriple parameter here, and
2216 /// should instead pull the target out of the driver. This is currently
2217 /// necessary because the driver doesn't store the final version of the target
2218 /// triple.
2219 void Generic_GCC::GCCInstallationDetector::init(
2220     const llvm::Triple &TargetTriple, const ArgList &Args) {
2221   llvm::Triple BiarchVariantTriple = TargetTriple.isArch32Bit()
2222                                          ? TargetTriple.get64BitArchVariant()
2223                                          : TargetTriple.get32BitArchVariant();
2224   // The library directories which may contain GCC installations.
2225   SmallVector<StringRef, 4> CandidateLibDirs, CandidateBiarchLibDirs;
2226   // The compatible GCC triples for this particular architecture.
2227   SmallVector<StringRef, 16> CandidateTripleAliases;
2228   SmallVector<StringRef, 16> CandidateBiarchTripleAliases;
2229   // Add some triples that we want to check first.
2230   CandidateTripleAliases.push_back(TargetTriple.str());
2231   std::string TripleNoVendor, BiarchTripleNoVendor;
2232   if (TargetTriple.getVendor() == llvm::Triple::UnknownVendor) {
2233     StringRef OSEnv = TargetTriple.getOSAndEnvironmentName();
2234     if (TargetTriple.getEnvironment() == llvm::Triple::GNUX32)
2235       OSEnv = "linux-gnu";
2236     TripleNoVendor = (TargetTriple.getArchName().str() + '-' + OSEnv).str();
2237     CandidateTripleAliases.push_back(TripleNoVendor);
2238     if (BiarchVariantTriple.getArch() != llvm::Triple::UnknownArch) {
2239       BiarchTripleNoVendor =
2240           (BiarchVariantTriple.getArchName().str() + '-' + OSEnv).str();
2241       CandidateBiarchTripleAliases.push_back(BiarchTripleNoVendor);
2242     }
2243   }
2244 
2245   CollectLibDirsAndTriples(TargetTriple, BiarchVariantTriple, CandidateLibDirs,
2246                            CandidateTripleAliases, CandidateBiarchLibDirs,
2247                            CandidateBiarchTripleAliases);
2248 
2249   // If --gcc-install-dir= is specified, skip filesystem detection.
2250   if (const Arg *A =
2251           Args.getLastArg(clang::driver::options::OPT_gcc_install_dir_EQ);
2252       A && A->getValue()[0]) {
2253     StringRef InstallDir = A->getValue();
2254     if (!ScanGCCForMultilibs(TargetTriple, Args, InstallDir, false)) {
2255       D.Diag(diag::err_drv_invalid_gcc_install_dir) << InstallDir;
2256     } else {
2257       (void)InstallDir.consume_back("/");
2258       StringRef VersionText = llvm::sys::path::filename(InstallDir);
2259       StringRef TripleText =
2260           llvm::sys::path::filename(llvm::sys::path::parent_path(InstallDir));
2261 
2262       Version = GCCVersion::Parse(VersionText);
2263       GCCTriple.setTriple(TripleText);
2264       GCCInstallPath = std::string(InstallDir);
2265       GCCParentLibPath = GCCInstallPath + "/../../..";
2266       IsValid = true;
2267     }
2268     return;
2269   }
2270 
2271   // If --gcc-triple is specified use this instead of trying to
2272   // auto-detect a triple.
2273   if (const Arg *A =
2274           Args.getLastArg(clang::driver::options::OPT_gcc_triple_EQ)) {
2275     StringRef GCCTriple = A->getValue();
2276     CandidateTripleAliases.clear();
2277     CandidateTripleAliases.push_back(GCCTriple);
2278   }
2279 
2280   // Compute the set of prefixes for our search.
2281   SmallVector<std::string, 8> Prefixes;
2282   StringRef GCCToolchainDir = getGCCToolchainDir(Args, D.SysRoot);
2283   if (GCCToolchainDir != "") {
2284     if (GCCToolchainDir.back() == '/')
2285       GCCToolchainDir = GCCToolchainDir.drop_back(); // remove the /
2286 
2287     Prefixes.push_back(std::string(GCCToolchainDir));
2288   } else {
2289     // If we have a SysRoot, try that first.
2290     if (!D.SysRoot.empty()) {
2291       Prefixes.push_back(D.SysRoot);
2292       AddDefaultGCCPrefixes(TargetTriple, Prefixes, D.SysRoot);
2293     }
2294 
2295     // Then look for gcc installed alongside clang.
2296     Prefixes.push_back(D.Dir + "/..");
2297 
2298     // Next, look for prefix(es) that correspond to distribution-supplied gcc
2299     // installations.
2300     if (D.SysRoot.empty()) {
2301       // Typically /usr.
2302       AddDefaultGCCPrefixes(TargetTriple, Prefixes, D.SysRoot);
2303     }
2304 
2305     // Try to respect gcc-config on Gentoo if --gcc-toolchain is not provided.
2306     // This avoids accidentally enforcing the system GCC version when using a
2307     // custom toolchain.
2308     SmallVector<StringRef, 16> GentooTestTriples;
2309     // Try to match an exact triple as target triple first.
2310     // e.g. crossdev -S x86_64-gentoo-linux-gnu will install gcc libs for
2311     // x86_64-gentoo-linux-gnu. But "clang -target x86_64-gentoo-linux-gnu"
2312     // may pick the libraries for x86_64-pc-linux-gnu even when exact matching
2313     // triple x86_64-gentoo-linux-gnu is present.
2314     GentooTestTriples.push_back(TargetTriple.str());
2315     GentooTestTriples.append(CandidateTripleAliases.begin(),
2316                              CandidateTripleAliases.end());
2317     if (ScanGentooConfigs(TargetTriple, Args, GentooTestTriples,
2318                           CandidateBiarchTripleAliases))
2319       return;
2320   }
2321 
2322   // Loop over the various components which exist and select the best GCC
2323   // installation available. GCC installs are ranked by version number.
2324   const GCCVersion VersionZero = GCCVersion::Parse("0.0.0");
2325   Version = VersionZero;
2326   for (const std::string &Prefix : Prefixes) {
2327     auto &VFS = D.getVFS();
2328     if (!VFS.exists(Prefix))
2329       continue;
2330     for (StringRef Suffix : CandidateLibDirs) {
2331       const std::string LibDir = concat(Prefix, Suffix);
2332       if (!VFS.exists(LibDir))
2333         continue;
2334       // Maybe filter out <libdir>/gcc and <libdir>/gcc-cross.
2335       bool GCCDirExists = VFS.exists(LibDir + "/gcc");
2336       bool GCCCrossDirExists = VFS.exists(LibDir + "/gcc-cross");
2337       for (StringRef Candidate : CandidateTripleAliases)
2338         ScanLibDirForGCCTriple(TargetTriple, Args, LibDir, Candidate, false,
2339                                GCCDirExists, GCCCrossDirExists);
2340     }
2341     for (StringRef Suffix : CandidateBiarchLibDirs) {
2342       const std::string LibDir = Prefix + Suffix.str();
2343       if (!VFS.exists(LibDir))
2344         continue;
2345       bool GCCDirExists = VFS.exists(LibDir + "/gcc");
2346       bool GCCCrossDirExists = VFS.exists(LibDir + "/gcc-cross");
2347       for (StringRef Candidate : CandidateBiarchTripleAliases)
2348         ScanLibDirForGCCTriple(TargetTriple, Args, LibDir, Candidate, true,
2349                                GCCDirExists, GCCCrossDirExists);
2350     }
2351 
2352     // Skip other prefixes once a GCC installation is found.
2353     if (Version > VersionZero)
2354       break;
2355   }
2356 }
2357 
2358 void Generic_GCC::GCCInstallationDetector::print(raw_ostream &OS) const {
2359   for (const auto &InstallPath : CandidateGCCInstallPaths)
2360     OS << "Found candidate GCC installation: " << InstallPath << "\n";
2361 
2362   if (!GCCInstallPath.empty())
2363     OS << "Selected GCC installation: " << GCCInstallPath << "\n";
2364 
2365   for (const auto &Multilib : Multilibs)
2366     OS << "Candidate multilib: " << Multilib << "\n";
2367 
2368   if (Multilibs.size() != 0 || !SelectedMultilib.isDefault())
2369     OS << "Selected multilib: " << SelectedMultilib << "\n";
2370 }
2371 
2372 bool Generic_GCC::GCCInstallationDetector::getBiarchSibling(Multilib &M) const {
2373   if (BiarchSibling) {
2374     M = *BiarchSibling;
2375     return true;
2376   }
2377   return false;
2378 }
2379 
2380 void Generic_GCC::GCCInstallationDetector::AddDefaultGCCPrefixes(
2381     const llvm::Triple &TargetTriple, SmallVectorImpl<std::string> &Prefixes,
2382     StringRef SysRoot) {
2383 
2384   if (TargetTriple.isOSHaiku()) {
2385     Prefixes.push_back(concat(SysRoot, "/boot/system/develop/tools"));
2386     return;
2387   }
2388 
2389   if (TargetTriple.isOSSolaris()) {
2390     // Solaris is a special case.
2391     // The GCC installation is under
2392     //   /usr/gcc/<major>.<minor>/lib/gcc/<triple>/<major>.<minor>.<patch>/
2393     // so we need to find those /usr/gcc/*/lib/gcc libdirs and go with
2394     // /usr/gcc/<version> as a prefix.
2395 
2396     SmallVector<std::pair<GCCVersion, std::string>, 8> SolarisPrefixes;
2397     std::string PrefixDir = concat(SysRoot, "/usr/gcc");
2398     std::error_code EC;
2399     for (llvm::vfs::directory_iterator LI = D.getVFS().dir_begin(PrefixDir, EC),
2400                                        LE;
2401          !EC && LI != LE; LI = LI.increment(EC)) {
2402       StringRef VersionText = llvm::sys::path::filename(LI->path());
2403       GCCVersion CandidateVersion = GCCVersion::Parse(VersionText);
2404 
2405       // Filter out obviously bad entries.
2406       if (CandidateVersion.Major == -1 || CandidateVersion.isOlderThan(4, 1, 1))
2407         continue;
2408 
2409       std::string CandidatePrefix = PrefixDir + "/" + VersionText.str();
2410       std::string CandidateLibPath = CandidatePrefix + "/lib/gcc";
2411       if (!D.getVFS().exists(CandidateLibPath))
2412         continue;
2413 
2414       SolarisPrefixes.emplace_back(
2415           std::make_pair(CandidateVersion, CandidatePrefix));
2416     }
2417     // Sort in reverse order so GCCInstallationDetector::init picks the latest.
2418     std::sort(SolarisPrefixes.rbegin(), SolarisPrefixes.rend());
2419     for (auto p : SolarisPrefixes)
2420       Prefixes.emplace_back(p.second);
2421     return;
2422   }
2423 
2424   // For Linux, if --sysroot is not specified, look for RHEL/CentOS devtoolsets
2425   // and gcc-toolsets.
2426   if (SysRoot.empty() && TargetTriple.getOS() == llvm::Triple::Linux &&
2427       D.getVFS().exists("/opt/rh")) {
2428     // TODO: We may want to remove this, since the functionality
2429     //   can be achieved using config files.
2430     Prefixes.push_back("/opt/rh/gcc-toolset-12/root/usr");
2431     Prefixes.push_back("/opt/rh/gcc-toolset-11/root/usr");
2432     Prefixes.push_back("/opt/rh/gcc-toolset-10/root/usr");
2433     Prefixes.push_back("/opt/rh/devtoolset-12/root/usr");
2434     Prefixes.push_back("/opt/rh/devtoolset-11/root/usr");
2435     Prefixes.push_back("/opt/rh/devtoolset-10/root/usr");
2436     Prefixes.push_back("/opt/rh/devtoolset-9/root/usr");
2437     Prefixes.push_back("/opt/rh/devtoolset-8/root/usr");
2438     Prefixes.push_back("/opt/rh/devtoolset-7/root/usr");
2439     Prefixes.push_back("/opt/rh/devtoolset-6/root/usr");
2440     Prefixes.push_back("/opt/rh/devtoolset-4/root/usr");
2441     Prefixes.push_back("/opt/rh/devtoolset-3/root/usr");
2442     Prefixes.push_back("/opt/rh/devtoolset-2/root/usr");
2443   }
2444 
2445   // Fall back to /usr which is used by most non-Solaris systems.
2446   Prefixes.push_back(concat(SysRoot, "/usr"));
2447 }
2448 
2449 /*static*/ void Generic_GCC::GCCInstallationDetector::CollectLibDirsAndTriples(
2450     const llvm::Triple &TargetTriple, const llvm::Triple &BiarchTriple,
2451     SmallVectorImpl<StringRef> &LibDirs,
2452     SmallVectorImpl<StringRef> &TripleAliases,
2453     SmallVectorImpl<StringRef> &BiarchLibDirs,
2454     SmallVectorImpl<StringRef> &BiarchTripleAliases) {
2455   // Declare a bunch of static data sets that we'll select between below. These
2456   // are specifically designed to always refer to string literals to avoid any
2457   // lifetime or initialization issues.
2458   //
2459   // The *Triples variables hard code some triples so that, for example,
2460   // --target=aarch64 (incomplete triple) can detect lib/aarch64-linux-gnu.
2461   // They are not needed when the user has correct LLVM_DEFAULT_TARGET_TRIPLE
2462   // and always uses the full --target (e.g. --target=aarch64-linux-gnu).  The
2463   // lists should shrink over time. Please don't add more elements to *Triples.
2464   static const char *const AArch64LibDirs[] = {"/lib64", "/lib"};
2465   static const char *const AArch64Triples[] = {
2466       "aarch64-none-linux-gnu", "aarch64-linux-gnu", "aarch64-redhat-linux",
2467       "aarch64-suse-linux"};
2468   static const char *const AArch64beLibDirs[] = {"/lib"};
2469   static const char *const AArch64beTriples[] = {"aarch64_be-none-linux-gnu"};
2470 
2471   static const char *const ARMLibDirs[] = {"/lib"};
2472   static const char *const ARMTriples[] = {"arm-linux-gnueabi"};
2473   static const char *const ARMHFTriples[] = {"arm-linux-gnueabihf",
2474                                              "armv7hl-redhat-linux-gnueabi",
2475                                              "armv6hl-suse-linux-gnueabi",
2476                                              "armv7hl-suse-linux-gnueabi"};
2477   static const char *const ARMebLibDirs[] = {"/lib"};
2478   static const char *const ARMebTriples[] = {"armeb-linux-gnueabi"};
2479   static const char *const ARMebHFTriples[] = {
2480       "armeb-linux-gnueabihf", "armebv7hl-redhat-linux-gnueabi"};
2481 
2482   static const char *const AVRLibDirs[] = {"/lib"};
2483   static const char *const AVRTriples[] = {"avr"};
2484 
2485   static const char *const CSKYLibDirs[] = {"/lib"};
2486   static const char *const CSKYTriples[] = {
2487       "csky-linux-gnuabiv2", "csky-linux-uclibcabiv2", "csky-elf-noneabiv2"};
2488 
2489   static const char *const X86_64LibDirs[] = {"/lib64", "/lib"};
2490   static const char *const X86_64Triples[] = {
2491       "x86_64-linux-gnu",       "x86_64-unknown-linux-gnu",
2492       "x86_64-pc-linux-gnu",    "x86_64-redhat-linux6E",
2493       "x86_64-redhat-linux",    "x86_64-suse-linux",
2494       "x86_64-manbo-linux-gnu", "x86_64-slackware-linux",
2495       "x86_64-unknown-linux",   "x86_64-amazon-linux"};
2496   static const char *const X32Triples[] = {"x86_64-linux-gnux32",
2497                                            "x86_64-pc-linux-gnux32"};
2498   static const char *const X32LibDirs[] = {"/libx32", "/lib"};
2499   static const char *const X86LibDirs[] = {"/lib32", "/lib"};
2500   static const char *const X86Triples[] = {
2501       "i586-linux-gnu",      "i686-linux-gnu",        "i686-pc-linux-gnu",
2502       "i386-redhat-linux6E", "i686-redhat-linux",     "i386-redhat-linux",
2503       "i586-suse-linux",     "i686-montavista-linux",
2504   };
2505 
2506   static const char *const LoongArch64LibDirs[] = {"/lib64", "/lib"};
2507   static const char *const LoongArch64Triples[] = {
2508       "loongarch64-linux-gnu", "loongarch64-unknown-linux-gnu"};
2509 
2510   static const char *const M68kLibDirs[] = {"/lib"};
2511   static const char *const M68kTriples[] = {"m68k-unknown-linux-gnu",
2512                                             "m68k-suse-linux"};
2513 
2514   static const char *const MIPSLibDirs[] = {"/libo32", "/lib"};
2515   static const char *const MIPSTriples[] = {
2516       "mips-linux-gnu", "mips-mti-linux", "mips-mti-linux-gnu",
2517       "mips-img-linux-gnu", "mipsisa32r6-linux-gnu"};
2518   static const char *const MIPSELLibDirs[] = {"/libo32", "/lib"};
2519   static const char *const MIPSELTriples[] = {"mipsel-linux-gnu",
2520                                               "mips-img-linux-gnu"};
2521 
2522   static const char *const MIPS64LibDirs[] = {"/lib64", "/lib"};
2523   static const char *const MIPS64Triples[] = {
2524       "mips-mti-linux-gnu", "mips-img-linux-gnu", "mips64-linux-gnuabi64",
2525       "mipsisa64r6-linux-gnu", "mipsisa64r6-linux-gnuabi64"};
2526   static const char *const MIPS64ELLibDirs[] = {"/lib64", "/lib"};
2527   static const char *const MIPS64ELTriples[] = {
2528       "mips-mti-linux-gnu", "mips-img-linux-gnu", "mips64el-linux-gnuabi64",
2529       "mipsisa64r6el-linux-gnu", "mipsisa64r6el-linux-gnuabi64"};
2530 
2531   static const char *const MIPSN32LibDirs[] = {"/lib32"};
2532   static const char *const MIPSN32Triples[] = {"mips64-linux-gnuabin32",
2533                                                "mipsisa64r6-linux-gnuabin32"};
2534   static const char *const MIPSN32ELLibDirs[] = {"/lib32"};
2535   static const char *const MIPSN32ELTriples[] = {
2536       "mips64el-linux-gnuabin32", "mipsisa64r6el-linux-gnuabin32"};
2537 
2538   static const char *const MSP430LibDirs[] = {"/lib"};
2539   static const char *const MSP430Triples[] = {"msp430-elf"};
2540 
2541   static const char *const PPCLibDirs[] = {"/lib32", "/lib"};
2542   static const char *const PPCTriples[] = {
2543       "powerpc-unknown-linux-gnu",
2544       // On 32-bit PowerPC systems running SUSE Linux, gcc is configured as a
2545       // 64-bit compiler which defaults to "-m32", hence "powerpc64-suse-linux".
2546       "powerpc64-suse-linux", "powerpc-montavista-linuxspe"};
2547   static const char *const PPCLELibDirs[] = {"/lib32", "/lib"};
2548   static const char *const PPCLETriples[] = {"powerpcle-unknown-linux-gnu",
2549                                              "powerpcle-linux-musl"};
2550 
2551   static const char *const PPC64LibDirs[] = {"/lib64", "/lib"};
2552   static const char *const PPC64Triples[] = {"powerpc64-unknown-linux-gnu",
2553                                              "powerpc64-suse-linux",
2554                                              "ppc64-redhat-linux"};
2555   static const char *const PPC64LELibDirs[] = {"/lib64", "/lib"};
2556   static const char *const PPC64LETriples[] = {
2557       "powerpc64le-unknown-linux-gnu", "powerpc64le-none-linux-gnu",
2558       "powerpc64le-suse-linux", "ppc64le-redhat-linux"};
2559 
2560   static const char *const RISCV32LibDirs[] = {"/lib32", "/lib"};
2561   static const char *const RISCV32Triples[] = {"riscv32-unknown-linux-gnu",
2562                                                "riscv32-unknown-elf"};
2563   static const char *const RISCV64LibDirs[] = {"/lib64", "/lib"};
2564   static const char *const RISCV64Triples[] = {"riscv64-unknown-linux-gnu",
2565                                                "riscv64-unknown-elf"};
2566 
2567   static const char *const SPARCv8LibDirs[] = {"/lib32", "/lib"};
2568   static const char *const SPARCv8Triples[] = {"sparc-linux-gnu",
2569                                                "sparcv8-linux-gnu"};
2570   static const char *const SPARCv9LibDirs[] = {"/lib64", "/lib"};
2571   static const char *const SPARCv9Triples[] = {"sparc64-linux-gnu",
2572                                                "sparcv9-linux-gnu"};
2573 
2574   static const char *const SystemZLibDirs[] = {"/lib64", "/lib"};
2575   static const char *const SystemZTriples[] = {
2576       "s390x-unknown-linux-gnu", "s390x-ibm-linux-gnu", "s390x-suse-linux",
2577       "s390x-redhat-linux"};
2578 
2579   using std::begin;
2580   using std::end;
2581 
2582   if (TargetTriple.isOSSolaris()) {
2583     static const char *const SolarisLibDirs[] = {"/lib"};
2584     static const char *const SolarisSparcV8Triples[] = {
2585         "sparc-sun-solaris2.11"};
2586     static const char *const SolarisSparcV9Triples[] = {
2587         "sparcv9-sun-solaris2.11"};
2588     static const char *const SolarisX86Triples[] = {"i386-pc-solaris2.11"};
2589     static const char *const SolarisX86_64Triples[] = {"x86_64-pc-solaris2.11"};
2590     LibDirs.append(begin(SolarisLibDirs), end(SolarisLibDirs));
2591     BiarchLibDirs.append(begin(SolarisLibDirs), end(SolarisLibDirs));
2592     switch (TargetTriple.getArch()) {
2593     case llvm::Triple::x86:
2594       TripleAliases.append(begin(SolarisX86Triples), end(SolarisX86Triples));
2595       BiarchTripleAliases.append(begin(SolarisX86_64Triples),
2596                                  end(SolarisX86_64Triples));
2597       break;
2598     case llvm::Triple::x86_64:
2599       TripleAliases.append(begin(SolarisX86_64Triples),
2600                            end(SolarisX86_64Triples));
2601       BiarchTripleAliases.append(begin(SolarisX86Triples),
2602                                  end(SolarisX86Triples));
2603       break;
2604     case llvm::Triple::sparc:
2605       TripleAliases.append(begin(SolarisSparcV8Triples),
2606                            end(SolarisSparcV8Triples));
2607       BiarchTripleAliases.append(begin(SolarisSparcV9Triples),
2608                                  end(SolarisSparcV9Triples));
2609       break;
2610     case llvm::Triple::sparcv9:
2611       TripleAliases.append(begin(SolarisSparcV9Triples),
2612                            end(SolarisSparcV9Triples));
2613       BiarchTripleAliases.append(begin(SolarisSparcV8Triples),
2614                                  end(SolarisSparcV8Triples));
2615       break;
2616     default:
2617       break;
2618     }
2619     return;
2620   }
2621 
2622   // Android targets should not use GNU/Linux tools or libraries.
2623   if (TargetTriple.isAndroid()) {
2624     static const char *const AArch64AndroidTriples[] = {
2625         "aarch64-linux-android"};
2626     static const char *const ARMAndroidTriples[] = {"arm-linux-androideabi"};
2627     static const char *const X86AndroidTriples[] = {"i686-linux-android"};
2628     static const char *const X86_64AndroidTriples[] = {"x86_64-linux-android"};
2629 
2630     switch (TargetTriple.getArch()) {
2631     case llvm::Triple::aarch64:
2632       LibDirs.append(begin(AArch64LibDirs), end(AArch64LibDirs));
2633       TripleAliases.append(begin(AArch64AndroidTriples),
2634                            end(AArch64AndroidTriples));
2635       break;
2636     case llvm::Triple::arm:
2637     case llvm::Triple::thumb:
2638       LibDirs.append(begin(ARMLibDirs), end(ARMLibDirs));
2639       TripleAliases.append(begin(ARMAndroidTriples), end(ARMAndroidTriples));
2640       break;
2641     case llvm::Triple::x86_64:
2642       LibDirs.append(begin(X86_64LibDirs), end(X86_64LibDirs));
2643       TripleAliases.append(begin(X86_64AndroidTriples),
2644                            end(X86_64AndroidTriples));
2645       BiarchLibDirs.append(begin(X86LibDirs), end(X86LibDirs));
2646       BiarchTripleAliases.append(begin(X86AndroidTriples),
2647                                  end(X86AndroidTriples));
2648       break;
2649     case llvm::Triple::x86:
2650       LibDirs.append(begin(X86LibDirs), end(X86LibDirs));
2651       TripleAliases.append(begin(X86AndroidTriples), end(X86AndroidTriples));
2652       BiarchLibDirs.append(begin(X86_64LibDirs), end(X86_64LibDirs));
2653       BiarchTripleAliases.append(begin(X86_64AndroidTriples),
2654                                  end(X86_64AndroidTriples));
2655       break;
2656     default:
2657       break;
2658     }
2659 
2660     return;
2661   }
2662 
2663   if (TargetTriple.isOSHurd()) {
2664     switch (TargetTriple.getArch()) {
2665     case llvm::Triple::x86_64:
2666       LibDirs.append(begin(X86_64LibDirs), end(X86_64LibDirs));
2667       TripleAliases.push_back("x86_64-gnu");
2668       break;
2669     case llvm::Triple::x86:
2670       LibDirs.append(begin(X86LibDirs), end(X86LibDirs));
2671       TripleAliases.push_back("i686-gnu");
2672       break;
2673     default:
2674       break;
2675     }
2676 
2677     return;
2678   }
2679 
2680   switch (TargetTriple.getArch()) {
2681   case llvm::Triple::aarch64:
2682     LibDirs.append(begin(AArch64LibDirs), end(AArch64LibDirs));
2683     TripleAliases.append(begin(AArch64Triples), end(AArch64Triples));
2684     BiarchLibDirs.append(begin(AArch64LibDirs), end(AArch64LibDirs));
2685     BiarchTripleAliases.append(begin(AArch64Triples), end(AArch64Triples));
2686     break;
2687   case llvm::Triple::aarch64_be:
2688     LibDirs.append(begin(AArch64beLibDirs), end(AArch64beLibDirs));
2689     TripleAliases.append(begin(AArch64beTriples), end(AArch64beTriples));
2690     BiarchLibDirs.append(begin(AArch64beLibDirs), end(AArch64beLibDirs));
2691     BiarchTripleAliases.append(begin(AArch64beTriples), end(AArch64beTriples));
2692     break;
2693   case llvm::Triple::arm:
2694   case llvm::Triple::thumb:
2695     LibDirs.append(begin(ARMLibDirs), end(ARMLibDirs));
2696     if (TargetTriple.getEnvironment() == llvm::Triple::GNUEABIHF ||
2697         TargetTriple.getEnvironment() == llvm::Triple::GNUEABIHFT64 ||
2698         TargetTriple.getEnvironment() == llvm::Triple::MuslEABIHF ||
2699         TargetTriple.getEnvironment() == llvm::Triple::EABIHF) {
2700       TripleAliases.append(begin(ARMHFTriples), end(ARMHFTriples));
2701     } else {
2702       TripleAliases.append(begin(ARMTriples), end(ARMTriples));
2703     }
2704     break;
2705   case llvm::Triple::armeb:
2706   case llvm::Triple::thumbeb:
2707     LibDirs.append(begin(ARMebLibDirs), end(ARMebLibDirs));
2708     if (TargetTriple.getEnvironment() == llvm::Triple::GNUEABIHF ||
2709         TargetTriple.getEnvironment() == llvm::Triple::GNUEABIHFT64 ||
2710         TargetTriple.getEnvironment() == llvm::Triple::MuslEABIHF ||
2711         TargetTriple.getEnvironment() == llvm::Triple::EABIHF) {
2712       TripleAliases.append(begin(ARMebHFTriples), end(ARMebHFTriples));
2713     } else {
2714       TripleAliases.append(begin(ARMebTriples), end(ARMebTriples));
2715     }
2716     break;
2717   case llvm::Triple::avr:
2718     LibDirs.append(begin(AVRLibDirs), end(AVRLibDirs));
2719     TripleAliases.append(begin(AVRTriples), end(AVRTriples));
2720     break;
2721   case llvm::Triple::csky:
2722     LibDirs.append(begin(CSKYLibDirs), end(CSKYLibDirs));
2723     TripleAliases.append(begin(CSKYTriples), end(CSKYTriples));
2724     break;
2725   case llvm::Triple::x86_64:
2726     if (TargetTriple.isX32()) {
2727       LibDirs.append(begin(X32LibDirs), end(X32LibDirs));
2728       TripleAliases.append(begin(X32Triples), end(X32Triples));
2729       BiarchLibDirs.append(begin(X86_64LibDirs), end(X86_64LibDirs));
2730       BiarchTripleAliases.append(begin(X86_64Triples), end(X86_64Triples));
2731     } else {
2732       LibDirs.append(begin(X86_64LibDirs), end(X86_64LibDirs));
2733       TripleAliases.append(begin(X86_64Triples), end(X86_64Triples));
2734       BiarchLibDirs.append(begin(X32LibDirs), end(X32LibDirs));
2735       BiarchTripleAliases.append(begin(X32Triples), end(X32Triples));
2736     }
2737     BiarchLibDirs.append(begin(X86LibDirs), end(X86LibDirs));
2738     BiarchTripleAliases.append(begin(X86Triples), end(X86Triples));
2739     break;
2740   case llvm::Triple::x86:
2741     LibDirs.append(begin(X86LibDirs), end(X86LibDirs));
2742     // MCU toolchain is 32 bit only and its triple alias is TargetTriple
2743     // itself, which will be appended below.
2744     if (!TargetTriple.isOSIAMCU()) {
2745       TripleAliases.append(begin(X86Triples), end(X86Triples));
2746       BiarchLibDirs.append(begin(X86_64LibDirs), end(X86_64LibDirs));
2747       BiarchTripleAliases.append(begin(X86_64Triples), end(X86_64Triples));
2748       BiarchLibDirs.append(begin(X32LibDirs), end(X32LibDirs));
2749       BiarchTripleAliases.append(begin(X32Triples), end(X32Triples));
2750     }
2751     break;
2752   // TODO: Handle loongarch32.
2753   case llvm::Triple::loongarch64:
2754     LibDirs.append(begin(LoongArch64LibDirs), end(LoongArch64LibDirs));
2755     TripleAliases.append(begin(LoongArch64Triples), end(LoongArch64Triples));
2756     break;
2757   case llvm::Triple::m68k:
2758     LibDirs.append(begin(M68kLibDirs), end(M68kLibDirs));
2759     TripleAliases.append(begin(M68kTriples), end(M68kTriples));
2760     break;
2761   case llvm::Triple::mips:
2762     LibDirs.append(begin(MIPSLibDirs), end(MIPSLibDirs));
2763     TripleAliases.append(begin(MIPSTriples), end(MIPSTriples));
2764     BiarchLibDirs.append(begin(MIPS64LibDirs), end(MIPS64LibDirs));
2765     BiarchTripleAliases.append(begin(MIPS64Triples), end(MIPS64Triples));
2766     BiarchLibDirs.append(begin(MIPSN32LibDirs), end(MIPSN32LibDirs));
2767     BiarchTripleAliases.append(begin(MIPSN32Triples), end(MIPSN32Triples));
2768     break;
2769   case llvm::Triple::mipsel:
2770     LibDirs.append(begin(MIPSELLibDirs), end(MIPSELLibDirs));
2771     TripleAliases.append(begin(MIPSELTriples), end(MIPSELTriples));
2772     TripleAliases.append(begin(MIPSTriples), end(MIPSTriples));
2773     BiarchLibDirs.append(begin(MIPS64ELLibDirs), end(MIPS64ELLibDirs));
2774     BiarchTripleAliases.append(begin(MIPS64ELTriples), end(MIPS64ELTriples));
2775     BiarchLibDirs.append(begin(MIPSN32ELLibDirs), end(MIPSN32ELLibDirs));
2776     BiarchTripleAliases.append(begin(MIPSN32ELTriples), end(MIPSN32ELTriples));
2777     break;
2778   case llvm::Triple::mips64:
2779     LibDirs.append(begin(MIPS64LibDirs), end(MIPS64LibDirs));
2780     TripleAliases.append(begin(MIPS64Triples), end(MIPS64Triples));
2781     BiarchLibDirs.append(begin(MIPSLibDirs), end(MIPSLibDirs));
2782     BiarchTripleAliases.append(begin(MIPSTriples), end(MIPSTriples));
2783     BiarchLibDirs.append(begin(MIPSN32LibDirs), end(MIPSN32LibDirs));
2784     BiarchTripleAliases.append(begin(MIPSN32Triples), end(MIPSN32Triples));
2785     break;
2786   case llvm::Triple::mips64el:
2787     LibDirs.append(begin(MIPS64ELLibDirs), end(MIPS64ELLibDirs));
2788     TripleAliases.append(begin(MIPS64ELTriples), end(MIPS64ELTriples));
2789     BiarchLibDirs.append(begin(MIPSELLibDirs), end(MIPSELLibDirs));
2790     BiarchTripleAliases.append(begin(MIPSELTriples), end(MIPSELTriples));
2791     BiarchLibDirs.append(begin(MIPSN32ELLibDirs), end(MIPSN32ELLibDirs));
2792     BiarchTripleAliases.append(begin(MIPSN32ELTriples), end(MIPSN32ELTriples));
2793     BiarchTripleAliases.append(begin(MIPSTriples), end(MIPSTriples));
2794     break;
2795   case llvm::Triple::msp430:
2796     LibDirs.append(begin(MSP430LibDirs), end(MSP430LibDirs));
2797     TripleAliases.append(begin(MSP430Triples), end(MSP430Triples));
2798     break;
2799   case llvm::Triple::ppc:
2800     LibDirs.append(begin(PPCLibDirs), end(PPCLibDirs));
2801     TripleAliases.append(begin(PPCTriples), end(PPCTriples));
2802     BiarchLibDirs.append(begin(PPC64LibDirs), end(PPC64LibDirs));
2803     BiarchTripleAliases.append(begin(PPC64Triples), end(PPC64Triples));
2804     break;
2805   case llvm::Triple::ppcle:
2806     LibDirs.append(begin(PPCLELibDirs), end(PPCLELibDirs));
2807     TripleAliases.append(begin(PPCLETriples), end(PPCLETriples));
2808     BiarchLibDirs.append(begin(PPC64LELibDirs), end(PPC64LELibDirs));
2809     BiarchTripleAliases.append(begin(PPC64LETriples), end(PPC64LETriples));
2810     break;
2811   case llvm::Triple::ppc64:
2812     LibDirs.append(begin(PPC64LibDirs), end(PPC64LibDirs));
2813     TripleAliases.append(begin(PPC64Triples), end(PPC64Triples));
2814     BiarchLibDirs.append(begin(PPCLibDirs), end(PPCLibDirs));
2815     BiarchTripleAliases.append(begin(PPCTriples), end(PPCTriples));
2816     break;
2817   case llvm::Triple::ppc64le:
2818     LibDirs.append(begin(PPC64LELibDirs), end(PPC64LELibDirs));
2819     TripleAliases.append(begin(PPC64LETriples), end(PPC64LETriples));
2820     BiarchLibDirs.append(begin(PPCLELibDirs), end(PPCLELibDirs));
2821     BiarchTripleAliases.append(begin(PPCLETriples), end(PPCLETriples));
2822     break;
2823   case llvm::Triple::riscv32:
2824     LibDirs.append(begin(RISCV32LibDirs), end(RISCV32LibDirs));
2825     TripleAliases.append(begin(RISCV32Triples), end(RISCV32Triples));
2826     BiarchLibDirs.append(begin(RISCV64LibDirs), end(RISCV64LibDirs));
2827     BiarchTripleAliases.append(begin(RISCV64Triples), end(RISCV64Triples));
2828     break;
2829   case llvm::Triple::riscv64:
2830     LibDirs.append(begin(RISCV64LibDirs), end(RISCV64LibDirs));
2831     TripleAliases.append(begin(RISCV64Triples), end(RISCV64Triples));
2832     BiarchLibDirs.append(begin(RISCV32LibDirs), end(RISCV32LibDirs));
2833     BiarchTripleAliases.append(begin(RISCV32Triples), end(RISCV32Triples));
2834     break;
2835   case llvm::Triple::sparc:
2836   case llvm::Triple::sparcel:
2837     LibDirs.append(begin(SPARCv8LibDirs), end(SPARCv8LibDirs));
2838     TripleAliases.append(begin(SPARCv8Triples), end(SPARCv8Triples));
2839     BiarchLibDirs.append(begin(SPARCv9LibDirs), end(SPARCv9LibDirs));
2840     BiarchTripleAliases.append(begin(SPARCv9Triples), end(SPARCv9Triples));
2841     break;
2842   case llvm::Triple::sparcv9:
2843     LibDirs.append(begin(SPARCv9LibDirs), end(SPARCv9LibDirs));
2844     TripleAliases.append(begin(SPARCv9Triples), end(SPARCv9Triples));
2845     BiarchLibDirs.append(begin(SPARCv8LibDirs), end(SPARCv8LibDirs));
2846     BiarchTripleAliases.append(begin(SPARCv8Triples), end(SPARCv8Triples));
2847     break;
2848   case llvm::Triple::systemz:
2849     LibDirs.append(begin(SystemZLibDirs), end(SystemZLibDirs));
2850     TripleAliases.append(begin(SystemZTriples), end(SystemZTriples));
2851     break;
2852   default:
2853     // By default, just rely on the standard lib directories and the original
2854     // triple.
2855     break;
2856   }
2857 
2858   // Also include the multiarch variant if it's different.
2859   if (TargetTriple.str() != BiarchTriple.str())
2860     BiarchTripleAliases.push_back(BiarchTriple.str());
2861 }
2862 
2863 bool Generic_GCC::GCCInstallationDetector::ScanGCCForMultilibs(
2864     const llvm::Triple &TargetTriple, const ArgList &Args,
2865     StringRef Path, bool NeedsBiarchSuffix) {
2866   llvm::Triple::ArchType TargetArch = TargetTriple.getArch();
2867   DetectedMultilibs Detected;
2868 
2869   // Android standalone toolchain could have multilibs for ARM and Thumb.
2870   // Debian mips multilibs behave more like the rest of the biarch ones,
2871   // so handle them there
2872   if (isArmOrThumbArch(TargetArch) && TargetTriple.isAndroid()) {
2873     // It should also work without multilibs in a simplified toolchain.
2874     findAndroidArmMultilibs(D, TargetTriple, Path, Args, Detected);
2875   } else if (TargetTriple.isCSKY()) {
2876     findCSKYMultilibs(D, TargetTriple, Path, Args, Detected);
2877   } else if (TargetTriple.isMIPS()) {
2878     if (!findMIPSMultilibs(D, TargetTriple, Path, Args, Detected))
2879       return false;
2880   } else if (TargetTriple.isRISCV()) {
2881     findRISCVMultilibs(D, TargetTriple, Path, Args, Detected);
2882   } else if (isMSP430(TargetArch)) {
2883     findMSP430Multilibs(D, TargetTriple, Path, Args, Detected);
2884   } else if (TargetArch == llvm::Triple::avr) {
2885     // AVR has no multilibs.
2886   } else if (!findBiarchMultilibs(D, TargetTriple, Path, Args,
2887                                   NeedsBiarchSuffix, Detected)) {
2888     return false;
2889   }
2890 
2891   Multilibs = Detected.Multilibs;
2892   SelectedMultilib = Detected.SelectedMultilibs.empty()
2893                          ? Multilib()
2894                          : Detected.SelectedMultilibs.back();
2895   BiarchSibling = Detected.BiarchSibling;
2896 
2897   return true;
2898 }
2899 
2900 void Generic_GCC::GCCInstallationDetector::ScanLibDirForGCCTriple(
2901     const llvm::Triple &TargetTriple, const ArgList &Args,
2902     const std::string &LibDir, StringRef CandidateTriple,
2903     bool NeedsBiarchSuffix, bool GCCDirExists, bool GCCCrossDirExists) {
2904   // Locations relative to the system lib directory where GCC's triple-specific
2905   // directories might reside.
2906   struct GCCLibSuffix {
2907     // Path from system lib directory to GCC triple-specific directory.
2908     std::string LibSuffix;
2909     // Path from GCC triple-specific directory back to system lib directory.
2910     // This is one '..' component per component in LibSuffix.
2911     StringRef ReversePath;
2912     // Whether this library suffix is relevant for the triple.
2913     bool Active;
2914   } Suffixes[] = {
2915       // This is the normal place.
2916       {"gcc/" + CandidateTriple.str(), "../..", GCCDirExists},
2917 
2918       // Debian puts cross-compilers in gcc-cross.
2919       {"gcc-cross/" + CandidateTriple.str(), "../..", GCCCrossDirExists},
2920 
2921       // The Freescale PPC SDK has the gcc libraries in
2922       // <sysroot>/usr/lib/<triple>/x.y.z so have a look there as well. Only do
2923       // this on Freescale triples, though, since some systems put a *lot* of
2924       // files in that location, not just GCC installation data.
2925       {CandidateTriple.str(), "..",
2926        TargetTriple.getVendor() == llvm::Triple::Freescale ||
2927            TargetTriple.getVendor() == llvm::Triple::OpenEmbedded}};
2928 
2929   for (auto &Suffix : Suffixes) {
2930     if (!Suffix.Active)
2931       continue;
2932 
2933     StringRef LibSuffix = Suffix.LibSuffix;
2934     std::error_code EC;
2935     for (llvm::vfs::directory_iterator
2936              LI = D.getVFS().dir_begin(LibDir + "/" + LibSuffix, EC),
2937              LE;
2938          !EC && LI != LE; LI = LI.increment(EC)) {
2939       StringRef VersionText = llvm::sys::path::filename(LI->path());
2940       GCCVersion CandidateVersion = GCCVersion::Parse(VersionText);
2941       if (CandidateVersion.Major != -1) // Filter obviously bad entries.
2942         if (!CandidateGCCInstallPaths.insert(std::string(LI->path())).second)
2943           continue; // Saw this path before; no need to look at it again.
2944       if (CandidateVersion.isOlderThan(4, 1, 1))
2945         continue;
2946       if (CandidateVersion <= Version)
2947         continue;
2948 
2949       if (!ScanGCCForMultilibs(TargetTriple, Args, LI->path(),
2950                                NeedsBiarchSuffix))
2951         continue;
2952 
2953       Version = CandidateVersion;
2954       GCCTriple.setTriple(CandidateTriple);
2955       // FIXME: We hack together the directory name here instead of
2956       // using LI to ensure stable path separators across Windows and
2957       // Linux.
2958       GCCInstallPath = (LibDir + "/" + LibSuffix + "/" + VersionText).str();
2959       GCCParentLibPath = (GCCInstallPath + "/../" + Suffix.ReversePath).str();
2960       IsValid = true;
2961     }
2962   }
2963 }
2964 
2965 bool Generic_GCC::GCCInstallationDetector::ScanGentooConfigs(
2966     const llvm::Triple &TargetTriple, const ArgList &Args,
2967     const SmallVectorImpl<StringRef> &CandidateTriples,
2968     const SmallVectorImpl<StringRef> &CandidateBiarchTriples) {
2969   if (!D.getVFS().exists(concat(D.SysRoot, GentooConfigDir)))
2970     return false;
2971 
2972   for (StringRef CandidateTriple : CandidateTriples) {
2973     if (ScanGentooGccConfig(TargetTriple, Args, CandidateTriple))
2974       return true;
2975   }
2976 
2977   for (StringRef CandidateTriple : CandidateBiarchTriples) {
2978     if (ScanGentooGccConfig(TargetTriple, Args, CandidateTriple, true))
2979       return true;
2980   }
2981   return false;
2982 }
2983 
2984 bool Generic_GCC::GCCInstallationDetector::ScanGentooGccConfig(
2985     const llvm::Triple &TargetTriple, const ArgList &Args,
2986     StringRef CandidateTriple, bool NeedsBiarchSuffix) {
2987   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
2988       D.getVFS().getBufferForFile(concat(D.SysRoot, GentooConfigDir,
2989                                          "/config-" + CandidateTriple.str()));
2990   if (File) {
2991     SmallVector<StringRef, 2> Lines;
2992     File.get()->getBuffer().split(Lines, "\n");
2993     for (StringRef Line : Lines) {
2994       Line = Line.trim();
2995       // CURRENT=triple-version
2996       if (!Line.consume_front("CURRENT="))
2997         continue;
2998       // Process the config file pointed to by CURRENT.
2999       llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> ConfigFile =
3000           D.getVFS().getBufferForFile(
3001               concat(D.SysRoot, GentooConfigDir, "/" + Line));
3002       std::pair<StringRef, StringRef> ActiveVersion = Line.rsplit('-');
3003       // List of paths to scan for libraries.
3004       SmallVector<StringRef, 4> GentooScanPaths;
3005       // Scan the Config file to find installed GCC libraries path.
3006       // Typical content of the GCC config file:
3007       // LDPATH="/usr/lib/gcc/x86_64-pc-linux-gnu/4.9.x:/usr/lib/gcc/
3008       // (continued from previous line) x86_64-pc-linux-gnu/4.9.x/32"
3009       // MANPATH="/usr/share/gcc-data/x86_64-pc-linux-gnu/4.9.x/man"
3010       // INFOPATH="/usr/share/gcc-data/x86_64-pc-linux-gnu/4.9.x/info"
3011       // STDCXX_INCDIR="/usr/lib/gcc/x86_64-pc-linux-gnu/4.9.x/include/g++-v4"
3012       // We are looking for the paths listed in LDPATH=... .
3013       if (ConfigFile) {
3014         SmallVector<StringRef, 2> ConfigLines;
3015         ConfigFile.get()->getBuffer().split(ConfigLines, "\n");
3016         for (StringRef ConfLine : ConfigLines) {
3017           ConfLine = ConfLine.trim();
3018           if (ConfLine.consume_front("LDPATH=")) {
3019             // Drop '"' from front and back if present.
3020             ConfLine.consume_back("\"");
3021             ConfLine.consume_front("\"");
3022             // Get all paths sperated by ':'
3023             ConfLine.split(GentooScanPaths, ':', -1, /*AllowEmpty*/ false);
3024           }
3025         }
3026       }
3027       // Test the path based on the version in /etc/env.d/gcc/config-{tuple}.
3028       std::string basePath = "/usr/lib/gcc/" + ActiveVersion.first.str() + "/"
3029           + ActiveVersion.second.str();
3030       GentooScanPaths.push_back(StringRef(basePath));
3031 
3032       // Scan all paths for GCC libraries.
3033       for (const auto &GentooScanPath : GentooScanPaths) {
3034         std::string GentooPath = concat(D.SysRoot, GentooScanPath);
3035         if (D.getVFS().exists(GentooPath + "/crtbegin.o")) {
3036           if (!ScanGCCForMultilibs(TargetTriple, Args, GentooPath,
3037                                    NeedsBiarchSuffix))
3038             continue;
3039 
3040           Version = GCCVersion::Parse(ActiveVersion.second);
3041           GCCInstallPath = GentooPath;
3042           GCCParentLibPath = GentooPath + std::string("/../../..");
3043           GCCTriple.setTriple(ActiveVersion.first);
3044           IsValid = true;
3045           return true;
3046         }
3047       }
3048     }
3049   }
3050 
3051   return false;
3052 }
3053 
3054 Generic_GCC::Generic_GCC(const Driver &D, const llvm::Triple &Triple,
3055                          const ArgList &Args)
3056     : ToolChain(D, Triple, Args), GCCInstallation(D),
3057       CudaInstallation(D, Triple, Args), RocmInstallation(D, Triple, Args) {
3058   getProgramPaths().push_back(getDriver().Dir);
3059 }
3060 
3061 Generic_GCC::~Generic_GCC() {}
3062 
3063 Tool *Generic_GCC::getTool(Action::ActionClass AC) const {
3064   switch (AC) {
3065   case Action::PreprocessJobClass:
3066     if (!Preprocess)
3067       Preprocess.reset(new clang::driver::tools::gcc::Preprocessor(*this));
3068     return Preprocess.get();
3069   case Action::CompileJobClass:
3070     if (!Compile)
3071       Compile.reset(new tools::gcc::Compiler(*this));
3072     return Compile.get();
3073   default:
3074     return ToolChain::getTool(AC);
3075   }
3076 }
3077 
3078 Tool *Generic_GCC::buildAssembler() const {
3079   return new tools::gnutools::Assembler(*this);
3080 }
3081 
3082 Tool *Generic_GCC::buildLinker() const { return new tools::gcc::Linker(*this); }
3083 
3084 void Generic_GCC::printVerboseInfo(raw_ostream &OS) const {
3085   // Print the information about how we detected the GCC installation.
3086   GCCInstallation.print(OS);
3087   CudaInstallation->print(OS);
3088   RocmInstallation->print(OS);
3089 }
3090 
3091 ToolChain::UnwindTableLevel
3092 Generic_GCC::getDefaultUnwindTableLevel(const ArgList &Args) const {
3093   switch (getArch()) {
3094   case llvm::Triple::aarch64:
3095   case llvm::Triple::aarch64_be:
3096   case llvm::Triple::ppc:
3097   case llvm::Triple::ppcle:
3098   case llvm::Triple::ppc64:
3099   case llvm::Triple::ppc64le:
3100   case llvm::Triple::riscv32:
3101   case llvm::Triple::riscv64:
3102   case llvm::Triple::x86:
3103   case llvm::Triple::x86_64:
3104     return UnwindTableLevel::Asynchronous;
3105   default:
3106     return UnwindTableLevel::None;
3107   }
3108 }
3109 
3110 bool Generic_GCC::isPICDefault() const {
3111   switch (getArch()) {
3112   case llvm::Triple::x86_64:
3113     return getTriple().isOSWindows();
3114   case llvm::Triple::mips64:
3115   case llvm::Triple::mips64el:
3116     return true;
3117   default:
3118     return false;
3119   }
3120 }
3121 
3122 bool Generic_GCC::isPIEDefault(const llvm::opt::ArgList &Args) const {
3123   return false;
3124 }
3125 
3126 bool Generic_GCC::isPICDefaultForced() const {
3127   return getArch() == llvm::Triple::x86_64 && getTriple().isOSWindows();
3128 }
3129 
3130 bool Generic_GCC::IsIntegratedAssemblerDefault() const {
3131   switch (getTriple().getArch()) {
3132   case llvm::Triple::nvptx:
3133   case llvm::Triple::nvptx64:
3134   case llvm::Triple::xcore:
3135     return false;
3136   default:
3137     return true;
3138   }
3139 }
3140 
3141 void Generic_GCC::PushPPaths(ToolChain::path_list &PPaths) {
3142   // Cross-compiling binutils and GCC installations (vanilla and openSUSE at
3143   // least) put various tools in a triple-prefixed directory off of the parent
3144   // of the GCC installation. We use the GCC triple here to ensure that we end
3145   // up with tools that support the same amount of cross compiling as the
3146   // detected GCC installation. For example, if we find a GCC installation
3147   // targeting x86_64, but it is a bi-arch GCC installation, it can also be
3148   // used to target i386.
3149   if (GCCInstallation.isValid()) {
3150     PPaths.push_back(Twine(GCCInstallation.getParentLibPath() + "/../" +
3151                            GCCInstallation.getTriple().str() + "/bin")
3152                          .str());
3153   }
3154 }
3155 
3156 void Generic_GCC::AddMultilibPaths(const Driver &D,
3157                                    const std::string &SysRoot,
3158                                    const std::string &OSLibDir,
3159                                    const std::string &MultiarchTriple,
3160                                    path_list &Paths) {
3161   // Add the multilib suffixed paths where they are available.
3162   if (GCCInstallation.isValid()) {
3163     assert(!SelectedMultilibs.empty());
3164     const llvm::Triple &GCCTriple = GCCInstallation.getTriple();
3165     const std::string &LibPath =
3166         std::string(GCCInstallation.getParentLibPath());
3167 
3168     // Sourcery CodeBench MIPS toolchain holds some libraries under
3169     // a biarch-like suffix of the GCC installation.
3170     if (const auto &PathsCallback = Multilibs.filePathsCallback())
3171       for (const auto &Path : PathsCallback(SelectedMultilibs.back()))
3172         addPathIfExists(D, GCCInstallation.getInstallPath() + Path, Paths);
3173 
3174     // Add lib/gcc/$triple/$version, with an optional /multilib suffix.
3175     addPathIfExists(D,
3176                     GCCInstallation.getInstallPath() +
3177                         SelectedMultilibs.back().gccSuffix(),
3178                     Paths);
3179 
3180     // Add lib/gcc/$triple/$libdir
3181     // For GCC built with --enable-version-specific-runtime-libs.
3182     addPathIfExists(D, GCCInstallation.getInstallPath() + "/../" + OSLibDir,
3183                     Paths);
3184 
3185     // GCC cross compiling toolchains will install target libraries which ship
3186     // as part of the toolchain under <prefix>/<triple>/<libdir> rather than as
3187     // any part of the GCC installation in
3188     // <prefix>/<libdir>/gcc/<triple>/<version>. This decision is somewhat
3189     // debatable, but is the reality today. We need to search this tree even
3190     // when we have a sysroot somewhere else. It is the responsibility of
3191     // whomever is doing the cross build targeting a sysroot using a GCC
3192     // installation that is *not* within the system root to ensure two things:
3193     //
3194     //  1) Any DSOs that are linked in from this tree or from the install path
3195     //     above must be present on the system root and found via an
3196     //     appropriate rpath.
3197     //  2) There must not be libraries installed into
3198     //     <prefix>/<triple>/<libdir> unless they should be preferred over
3199     //     those within the system root.
3200     //
3201     // Note that this matches the GCC behavior. See the below comment for where
3202     // Clang diverges from GCC's behavior.
3203     addPathIfExists(D,
3204                     LibPath + "/../" + GCCTriple.str() + "/lib/../" + OSLibDir +
3205                         SelectedMultilibs.back().osSuffix(),
3206                     Paths);
3207 
3208     // If the GCC installation we found is inside of the sysroot, we want to
3209     // prefer libraries installed in the parent prefix of the GCC installation.
3210     // It is important to *not* use these paths when the GCC installation is
3211     // outside of the system root as that can pick up unintended libraries.
3212     // This usually happens when there is an external cross compiler on the
3213     // host system, and a more minimal sysroot available that is the target of
3214     // the cross. Note that GCC does include some of these directories in some
3215     // configurations but this seems somewhere between questionable and simply
3216     // a bug.
3217     if (StringRef(LibPath).starts_with(SysRoot))
3218       addPathIfExists(D, LibPath + "/../" + OSLibDir, Paths);
3219   }
3220 }
3221 
3222 void Generic_GCC::AddMultiarchPaths(const Driver &D,
3223                                     const std::string &SysRoot,
3224                                     const std::string &OSLibDir,
3225                                     path_list &Paths) {
3226   if (GCCInstallation.isValid()) {
3227     const std::string &LibPath =
3228         std::string(GCCInstallation.getParentLibPath());
3229     const llvm::Triple &GCCTriple = GCCInstallation.getTriple();
3230     const Multilib &Multilib = GCCInstallation.getMultilib();
3231     addPathIfExists(
3232         D, LibPath + "/../" + GCCTriple.str() + "/lib" + Multilib.osSuffix(),
3233                     Paths);
3234   }
3235 }
3236 
3237 void Generic_GCC::AddMultilibIncludeArgs(const ArgList &DriverArgs,
3238                                          ArgStringList &CC1Args) const {
3239   // Add include directories specific to the selected multilib set and multilib.
3240   if (!GCCInstallation.isValid())
3241     return;
3242   // gcc TOOL_INCLUDE_DIR.
3243   const llvm::Triple &GCCTriple = GCCInstallation.getTriple();
3244   std::string LibPath(GCCInstallation.getParentLibPath());
3245   addSystemInclude(DriverArgs, CC1Args,
3246                    Twine(LibPath) + "/../" + GCCTriple.str() + "/include");
3247 
3248   const auto &Callback = Multilibs.includeDirsCallback();
3249   if (Callback) {
3250     for (const auto &Path : Callback(GCCInstallation.getMultilib()))
3251       addExternCSystemIncludeIfExists(DriverArgs, CC1Args,
3252                                       GCCInstallation.getInstallPath() + Path);
3253   }
3254 }
3255 
3256 void Generic_GCC::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
3257                                                ArgStringList &CC1Args) const {
3258   if (DriverArgs.hasArg(options::OPT_nostdinc, options::OPT_nostdincxx,
3259                         options::OPT_nostdlibinc))
3260     return;
3261 
3262   switch (GetCXXStdlibType(DriverArgs)) {
3263   case ToolChain::CST_Libcxx:
3264     addLibCxxIncludePaths(DriverArgs, CC1Args);
3265     break;
3266 
3267   case ToolChain::CST_Libstdcxx:
3268     addLibStdCxxIncludePaths(DriverArgs, CC1Args);
3269     break;
3270   }
3271 }
3272 
3273 void
3274 Generic_GCC::addLibCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
3275                                    llvm::opt::ArgStringList &CC1Args) const {
3276   const Driver &D = getDriver();
3277   std::string SysRoot = computeSysRoot();
3278   if (SysRoot.empty())
3279     SysRoot = llvm::sys::path::get_separator();
3280 
3281   auto AddIncludePath = [&](StringRef Path, bool TargetDirRequired = false) {
3282     std::string Version = detectLibcxxVersion(Path);
3283     if (Version.empty())
3284       return false;
3285 
3286     // First add the per-target include path if it exists.
3287     bool TargetDirExists = false;
3288     std::optional<std::string> TargetIncludeDir = getTargetSubDirPath(Path);
3289     if (TargetIncludeDir) {
3290       SmallString<128> TargetDir(*TargetIncludeDir);
3291       llvm::sys::path::append(TargetDir, "c++", Version);
3292       if (D.getVFS().exists(TargetDir)) {
3293         addSystemInclude(DriverArgs, CC1Args, TargetDir);
3294         TargetDirExists = true;
3295       }
3296     }
3297     if (TargetDirRequired && !TargetDirExists)
3298       return false;
3299 
3300     // Second add the generic one.
3301     SmallString<128> GenericDir(Path);
3302     llvm::sys::path::append(GenericDir, "c++", Version);
3303     addSystemInclude(DriverArgs, CC1Args, GenericDir);
3304     return true;
3305   };
3306 
3307   // Android only uses the libc++ headers installed alongside the toolchain if
3308   // they contain an Android-specific target include path, otherwise they're
3309   // incompatible with the NDK libraries.
3310   SmallString<128> DriverIncludeDir(getDriver().Dir);
3311   llvm::sys::path::append(DriverIncludeDir, "..", "include");
3312   if (AddIncludePath(DriverIncludeDir,
3313                      /*TargetDirRequired=*/getTriple().isAndroid()))
3314     return;
3315   // If this is a development, non-installed, clang, libcxx will
3316   // not be found at ../include/c++ but it likely to be found at
3317   // one of the following two locations:
3318   SmallString<128> UsrLocalIncludeDir(SysRoot);
3319   llvm::sys::path::append(UsrLocalIncludeDir, "usr", "local", "include");
3320   if (AddIncludePath(UsrLocalIncludeDir))
3321     return;
3322   SmallString<128> UsrIncludeDir(SysRoot);
3323   llvm::sys::path::append(UsrIncludeDir, "usr", "include");
3324   if (AddIncludePath(UsrIncludeDir))
3325     return;
3326 }
3327 
3328 bool Generic_GCC::addLibStdCXXIncludePaths(Twine IncludeDir, StringRef Triple,
3329                                            Twine IncludeSuffix,
3330                                            const llvm::opt::ArgList &DriverArgs,
3331                                            llvm::opt::ArgStringList &CC1Args,
3332                                            bool DetectDebian) const {
3333   if (!getVFS().exists(IncludeDir))
3334     return false;
3335 
3336   // Debian native gcc uses g++-multiarch-incdir.diff which uses
3337   // include/x86_64-linux-gnu/c++/10$IncludeSuffix instead of
3338   // include/c++/10/x86_64-linux-gnu$IncludeSuffix.
3339   std::string Dir = IncludeDir.str();
3340   StringRef Include =
3341       llvm::sys::path::parent_path(llvm::sys::path::parent_path(Dir));
3342   std::string Path =
3343       (Include + "/" + Triple + Dir.substr(Include.size()) + IncludeSuffix)
3344           .str();
3345   if (DetectDebian && !getVFS().exists(Path))
3346     return false;
3347 
3348   // GPLUSPLUS_INCLUDE_DIR
3349   addSystemInclude(DriverArgs, CC1Args, IncludeDir);
3350   // GPLUSPLUS_TOOL_INCLUDE_DIR. If Triple is not empty, add a target-dependent
3351   // include directory.
3352   if (DetectDebian)
3353     addSystemInclude(DriverArgs, CC1Args, Path);
3354   else if (!Triple.empty())
3355     addSystemInclude(DriverArgs, CC1Args,
3356                      IncludeDir + "/" + Triple + IncludeSuffix);
3357   // GPLUSPLUS_BACKWARD_INCLUDE_DIR
3358   addSystemInclude(DriverArgs, CC1Args, IncludeDir + "/backward");
3359   return true;
3360 }
3361 
3362 bool Generic_GCC::addGCCLibStdCxxIncludePaths(
3363     const llvm::opt::ArgList &DriverArgs, llvm::opt::ArgStringList &CC1Args,
3364     StringRef DebianMultiarch) const {
3365   assert(GCCInstallation.isValid());
3366 
3367   // By default, look for the C++ headers in an include directory adjacent to
3368   // the lib directory of the GCC installation. Note that this is expect to be
3369   // equivalent to '/usr/include/c++/X.Y' in almost all cases.
3370   StringRef LibDir = GCCInstallation.getParentLibPath();
3371   StringRef InstallDir = GCCInstallation.getInstallPath();
3372   StringRef TripleStr = GCCInstallation.getTriple().str();
3373   const Multilib &Multilib = GCCInstallation.getMultilib();
3374   const GCCVersion &Version = GCCInstallation.getVersion();
3375 
3376   // Try /../$triple/include/c++/$version (gcc --print-multiarch is not empty).
3377   if (addLibStdCXXIncludePaths(
3378           LibDir.str() + "/../" + TripleStr + "/include/c++/" + Version.Text,
3379           TripleStr, Multilib.includeSuffix(), DriverArgs, CC1Args))
3380     return true;
3381 
3382   // Try /gcc/$triple/$version/include/c++/ (gcc --print-multiarch is not
3383   // empty). Like above but for GCC built with
3384   // --enable-version-specific-runtime-libs.
3385   if (addLibStdCXXIncludePaths(LibDir.str() + "/gcc/" + TripleStr + "/" +
3386                                    Version.Text + "/include/c++/",
3387                                TripleStr, Multilib.includeSuffix(), DriverArgs,
3388                                CC1Args))
3389     return true;
3390 
3391   // Detect Debian g++-multiarch-incdir.diff.
3392   if (addLibStdCXXIncludePaths(LibDir.str() + "/../include/c++/" + Version.Text,
3393                                DebianMultiarch, Multilib.includeSuffix(),
3394                                DriverArgs, CC1Args, /*Debian=*/true))
3395     return true;
3396 
3397   // Try /../include/c++/$version (gcc --print-multiarch is empty).
3398   if (addLibStdCXXIncludePaths(LibDir.str() + "/../include/c++/" + Version.Text,
3399                                TripleStr, Multilib.includeSuffix(), DriverArgs,
3400                                CC1Args))
3401     return true;
3402 
3403   // Otherwise, fall back on a bunch of options which don't use multiarch
3404   // layouts for simplicity.
3405   const std::string LibStdCXXIncludePathCandidates[] = {
3406       // Gentoo is weird and places its headers inside the GCC install,
3407       // so if the first attempt to find the headers fails, try these patterns.
3408       InstallDir.str() + "/include/g++-v" + Version.Text,
3409       InstallDir.str() + "/include/g++-v" + Version.MajorStr + "." +
3410           Version.MinorStr,
3411       InstallDir.str() + "/include/g++-v" + Version.MajorStr,
3412   };
3413 
3414   for (const auto &IncludePath : LibStdCXXIncludePathCandidates) {
3415     if (addLibStdCXXIncludePaths(IncludePath, TripleStr,
3416                                  Multilib.includeSuffix(), DriverArgs, CC1Args))
3417       return true;
3418   }
3419   return false;
3420 }
3421 
3422 void
3423 Generic_GCC::addLibStdCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
3424                                       llvm::opt::ArgStringList &CC1Args) const {
3425   if (GCCInstallation.isValid()) {
3426     addGCCLibStdCxxIncludePaths(DriverArgs, CC1Args,
3427                                 GCCInstallation.getTriple().str());
3428   }
3429 }
3430 
3431 llvm::opt::DerivedArgList *
3432 Generic_GCC::TranslateArgs(const llvm::opt::DerivedArgList &Args, StringRef,
3433                            Action::OffloadKind DeviceOffloadKind) const {
3434 
3435   // If this tool chain is used for an OpenMP offloading device we have to make
3436   // sure we always generate a shared library regardless of the commands the
3437   // user passed to the host. This is required because the runtime library
3438   // is required to load the device image dynamically at run time.
3439   if (DeviceOffloadKind == Action::OFK_OpenMP) {
3440     DerivedArgList *DAL = new DerivedArgList(Args.getBaseArgs());
3441     const OptTable &Opts = getDriver().getOpts();
3442 
3443     // Request the shared library. Given that these options are decided
3444     // implicitly, they do not refer to any base argument.
3445     DAL->AddFlagArg(/*BaseArg=*/nullptr, Opts.getOption(options::OPT_shared));
3446     DAL->AddFlagArg(/*BaseArg=*/nullptr, Opts.getOption(options::OPT_fPIC));
3447 
3448     // Filter all the arguments we don't care passing to the offloading
3449     // toolchain as they can mess up with the creation of a shared library.
3450     for (auto *A : Args) {
3451       switch ((options::ID)A->getOption().getID()) {
3452       default:
3453         DAL->append(A);
3454         break;
3455       case options::OPT_shared:
3456       case options::OPT_dynamic:
3457       case options::OPT_static:
3458       case options::OPT_fPIC:
3459       case options::OPT_fno_PIC:
3460       case options::OPT_fpic:
3461       case options::OPT_fno_pic:
3462       case options::OPT_fPIE:
3463       case options::OPT_fno_PIE:
3464       case options::OPT_fpie:
3465       case options::OPT_fno_pie:
3466         break;
3467       }
3468     }
3469     return DAL;
3470   }
3471   return nullptr;
3472 }
3473 
3474 void Generic_ELF::anchor() {}
3475 
3476 void Generic_ELF::addClangTargetOptions(const ArgList &DriverArgs,
3477                                         ArgStringList &CC1Args,
3478                                         Action::OffloadKind) const {
3479   if (!DriverArgs.hasFlag(options::OPT_fuse_init_array,
3480                           options::OPT_fno_use_init_array, true))
3481     CC1Args.push_back("-fno-use-init-array");
3482 }
3483