1//===--- Fuchsia.cpp - Fuchsia 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 "Fuchsia.h"
10#include "CommonArgs.h"
11#include "clang/Config/config.h"
12#include "clang/Driver/Compilation.h"
13#include "clang/Driver/Driver.h"
14#include "clang/Driver/DriverDiagnostic.h"
15#include "clang/Driver/Options.h"
16#include "clang/Driver/SanitizerArgs.h"
17#include "llvm/Option/ArgList.h"
18#include "llvm/ProfileData/InstrProf.h"
19#include "llvm/Support/FileSystem.h"
20#include "llvm/Support/Path.h"
21#include "llvm/Support/VirtualFileSystem.h"
22
23using namespace clang::driver;
24using namespace clang::driver::toolchains;
25using namespace clang::driver::tools;
26using namespace clang;
27using namespace llvm::opt;
28
29using tools::addMultilibFlag;
30
31void fuchsia::Linker::ConstructJob(Compilation &C, const JobAction &JA,
32                                   const InputInfo &Output,
33                                   const InputInfoList &Inputs,
34                                   const ArgList &Args,
35                                   const char *LinkingOutput) const {
36  const toolchains::Fuchsia &ToolChain =
37      static_cast<const toolchains::Fuchsia &>(getToolChain());
38  const Driver &D = ToolChain.getDriver();
39
40  ArgStringList CmdArgs;
41
42  // Silence warning for "clang -g foo.o -o foo"
43  Args.ClaimAllArgs(options::OPT_g_Group);
44  // and "clang -emit-llvm foo.o -o foo"
45  Args.ClaimAllArgs(options::OPT_emit_llvm);
46  // and for "clang -w foo.o -o foo". Other warning options are already
47  // handled somewhere else.
48  Args.ClaimAllArgs(options::OPT_w);
49
50  CmdArgs.push_back("-z");
51  CmdArgs.push_back("max-page-size=4096");
52
53  CmdArgs.push_back("-z");
54  CmdArgs.push_back("now");
55
56  const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
57  if (llvm::sys::path::filename(Exec).equals_lower("ld.lld") ||
58      llvm::sys::path::stem(Exec).equals_lower("ld.lld")) {
59    CmdArgs.push_back("-z");
60    CmdArgs.push_back("rodynamic");
61    CmdArgs.push_back("-z");
62    CmdArgs.push_back("separate-loadable-segments");
63    CmdArgs.push_back("--pack-dyn-relocs=relr");
64  }
65
66  if (!D.SysRoot.empty())
67    CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
68
69  if (!Args.hasArg(options::OPT_shared) && !Args.hasArg(options::OPT_r))
70    CmdArgs.push_back("-pie");
71
72  if (Args.hasArg(options::OPT_rdynamic))
73    CmdArgs.push_back("-export-dynamic");
74
75  if (Args.hasArg(options::OPT_s))
76    CmdArgs.push_back("-s");
77
78  if (Args.hasArg(options::OPT_r)) {
79    CmdArgs.push_back("-r");
80  } else {
81    CmdArgs.push_back("--build-id");
82    CmdArgs.push_back("--hash-style=gnu");
83  }
84
85  CmdArgs.push_back("--eh-frame-hdr");
86
87  if (Args.hasArg(options::OPT_static))
88    CmdArgs.push_back("-Bstatic");
89  else if (Args.hasArg(options::OPT_shared))
90    CmdArgs.push_back("-shared");
91
92  const SanitizerArgs &SanArgs = ToolChain.getSanitizerArgs();
93
94  if (!Args.hasArg(options::OPT_shared)) {
95    std::string Dyld = D.DyldPrefix;
96    if (SanArgs.needsAsanRt() && SanArgs.needsSharedRt())
97      Dyld += "asan/";
98    if (SanArgs.needsHwasanRt() && SanArgs.needsSharedRt())
99      Dyld += "hwasan/";
100    if (SanArgs.needsTsanRt() && SanArgs.needsSharedRt())
101      Dyld += "tsan/";
102    Dyld += "ld.so.1";
103    CmdArgs.push_back("-dynamic-linker");
104    CmdArgs.push_back(Args.MakeArgString(Dyld));
105  }
106
107  CmdArgs.push_back("-o");
108  CmdArgs.push_back(Output.getFilename());
109
110  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
111    if (!Args.hasArg(options::OPT_shared)) {
112      CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("Scrt1.o")));
113    }
114  }
115
116  Args.AddAllArgs(CmdArgs, options::OPT_L);
117  Args.AddAllArgs(CmdArgs, options::OPT_u);
118
119  ToolChain.AddFilePathLibArgs(Args, CmdArgs);
120
121  if (D.isUsingLTO()) {
122    assert(!Inputs.empty() && "Must have at least one input.");
123    addLTOOptions(ToolChain, Args, CmdArgs, Output, Inputs[0],
124                  D.getLTOMode() == LTOK_Thin);
125  }
126
127  bool NeedsSanitizerDeps = addSanitizerRuntimes(ToolChain, Args, CmdArgs);
128  bool NeedsXRayDeps = addXRayRuntime(ToolChain, Args, CmdArgs);
129  AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
130  ToolChain.addProfileRTLibs(Args, CmdArgs);
131
132  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
133    if (Args.hasArg(options::OPT_static))
134      CmdArgs.push_back("-Bdynamic");
135
136    if (D.CCCIsCXX()) {
137      if (ToolChain.ShouldLinkCXXStdlib(Args)) {
138        bool OnlyLibstdcxxStatic = Args.hasArg(options::OPT_static_libstdcxx) &&
139                                   !Args.hasArg(options::OPT_static);
140        CmdArgs.push_back("--push-state");
141        CmdArgs.push_back("--as-needed");
142        if (OnlyLibstdcxxStatic)
143          CmdArgs.push_back("-Bstatic");
144        ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
145        if (OnlyLibstdcxxStatic)
146          CmdArgs.push_back("-Bdynamic");
147        CmdArgs.push_back("-lm");
148        CmdArgs.push_back("--pop-state");
149      }
150    }
151
152    if (NeedsSanitizerDeps)
153      linkSanitizerRuntimeDeps(ToolChain, CmdArgs);
154
155    if (NeedsXRayDeps)
156      linkXRayRuntimeDeps(ToolChain, CmdArgs);
157
158    AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
159
160    if (Args.hasArg(options::OPT_pthread) ||
161        Args.hasArg(options::OPT_pthreads))
162      CmdArgs.push_back("-lpthread");
163
164    if (Args.hasArg(options::OPT_fsplit_stack))
165      CmdArgs.push_back("--wrap=pthread_create");
166
167    if (!Args.hasArg(options::OPT_nolibc))
168      CmdArgs.push_back("-lc");
169  }
170
171  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
172                                         Exec, CmdArgs, Inputs, Output));
173}
174
175/// Fuchsia - Fuchsia tool chain which can call as(1) and ld(1) directly.
176
177Fuchsia::Fuchsia(const Driver &D, const llvm::Triple &Triple,
178                 const ArgList &Args)
179    : ToolChain(D, Triple, Args) {
180  getProgramPaths().push_back(getDriver().getInstalledDir());
181  if (getDriver().getInstalledDir() != D.Dir)
182    getProgramPaths().push_back(D.Dir);
183
184  if (!D.SysRoot.empty()) {
185    SmallString<128> P(D.SysRoot);
186    llvm::sys::path::append(P, "lib");
187    getFilePaths().push_back(std::string(P.str()));
188  }
189
190  auto FilePaths = [&](const Multilib &M) -> std::vector<std::string> {
191    std::vector<std::string> FP;
192    SmallString<128> P(getStdlibPath());
193    llvm::sys::path::append(P, M.gccSuffix());
194    FP.push_back(std::string(P.str()));
195    return FP;
196  };
197
198  Multilibs.push_back(Multilib());
199  // Use the noexcept variant with -fno-exceptions to avoid the extra overhead.
200  Multilibs.push_back(Multilib("noexcept", {}, {}, 1)
201                          .flag("-fexceptions")
202                          .flag("+fno-exceptions"));
203  // ASan has higher priority because we always want the instrumentated version.
204  Multilibs.push_back(Multilib("asan", {}, {}, 2)
205                          .flag("+fsanitize=address"));
206  // Use the asan+noexcept variant with ASan and -fno-exceptions.
207  Multilibs.push_back(Multilib("asan+noexcept", {}, {}, 3)
208                          .flag("+fsanitize=address")
209                          .flag("-fexceptions")
210                          .flag("+fno-exceptions"));
211  // HWASan has higher priority because we always want the instrumentated
212  // version.
213  Multilibs.push_back(
214      Multilib("hwasan", {}, {}, 4).flag("+fsanitize=hwaddress"));
215  // Use the hwasan+noexcept variant with HWASan and -fno-exceptions.
216  Multilibs.push_back(Multilib("hwasan+noexcept", {}, {}, 5)
217                          .flag("+fsanitize=hwaddress")
218                          .flag("-fexceptions")
219                          .flag("+fno-exceptions"));
220  // Use the relative vtables ABI.
221  // TODO: Remove these multilibs once relative vtables are enabled by default
222  // for Fuchsia.
223  Multilibs.push_back(Multilib("relative-vtables", {}, {}, 6)
224                          .flag("+fexperimental-relative-c++-abi-vtables"));
225  Multilibs.push_back(Multilib("relative-vtables+noexcept", {}, {}, 7)
226                          .flag("+fexperimental-relative-c++-abi-vtables")
227                          .flag("-fexceptions")
228                          .flag("+fno-exceptions"));
229  Multilibs.push_back(Multilib("relative-vtables+asan", {}, {}, 8)
230                          .flag("+fexperimental-relative-c++-abi-vtables")
231                          .flag("+fsanitize=address"));
232  Multilibs.push_back(Multilib("relative-vtables+asan+noexcept", {}, {}, 9)
233                          .flag("+fexperimental-relative-c++-abi-vtables")
234                          .flag("+fsanitize=address")
235                          .flag("-fexceptions")
236                          .flag("+fno-exceptions"));
237  Multilibs.push_back(Multilib("relative-vtables+hwasan", {}, {}, 10)
238                          .flag("+fexperimental-relative-c++-abi-vtables")
239                          .flag("+fsanitize=hwaddress"));
240  Multilibs.push_back(Multilib("relative-vtables+hwasan+noexcept", {}, {}, 11)
241                          .flag("+fexperimental-relative-c++-abi-vtables")
242                          .flag("+fsanitize=hwaddress")
243                          .flag("-fexceptions")
244                          .flag("+fno-exceptions"));
245  // Use Itanium C++ ABI for the compat multilib.
246  Multilibs.push_back(Multilib("compat", {}, {}, 12).flag("+fc++-abi=itanium"));
247
248  Multilibs.FilterOut([&](const Multilib &M) {
249    std::vector<std::string> RD = FilePaths(M);
250    return std::all_of(RD.begin(), RD.end(), [&](std::string P) {
251      return !getVFS().exists(P);
252    });
253  });
254
255  Multilib::flags_list Flags;
256  addMultilibFlag(
257      Args.hasFlag(options::OPT_fexceptions, options::OPT_fno_exceptions, true),
258      "fexceptions", Flags);
259  addMultilibFlag(getSanitizerArgs().needsAsanRt(), "fsanitize=address", Flags);
260  addMultilibFlag(getSanitizerArgs().needsHwasanRt(), "fsanitize=hwaddress",
261                  Flags);
262
263  addMultilibFlag(
264      Args.hasFlag(options::OPT_fexperimental_relative_cxx_abi_vtables,
265                   options::OPT_fno_experimental_relative_cxx_abi_vtables,
266                   /*default=*/false),
267      "fexperimental-relative-c++-abi-vtables", Flags);
268  addMultilibFlag(Args.getLastArgValue(options::OPT_fcxx_abi_EQ) == "itanium",
269                  "fc++-abi=itanium", Flags);
270
271  Multilibs.setFilePathsCallback(FilePaths);
272
273  if (Multilibs.select(Flags, SelectedMultilib))
274    if (!SelectedMultilib.isDefault())
275      if (const auto &PathsCallback = Multilibs.filePathsCallback())
276        for (const auto &Path : PathsCallback(SelectedMultilib))
277          // Prepend the multilib path to ensure it takes the precedence.
278          getFilePaths().insert(getFilePaths().begin(), Path);
279}
280
281std::string Fuchsia::ComputeEffectiveClangTriple(const ArgList &Args,
282                                                 types::ID InputType) const {
283  llvm::Triple Triple(ComputeLLVMTriple(Args, InputType));
284  return Triple.str();
285}
286
287Tool *Fuchsia::buildLinker() const {
288  return new tools::fuchsia::Linker(*this);
289}
290
291ToolChain::RuntimeLibType Fuchsia::GetRuntimeLibType(
292    const ArgList &Args) const {
293  if (Arg *A = Args.getLastArg(clang::driver::options::OPT_rtlib_EQ)) {
294    StringRef Value = A->getValue();
295    if (Value != "compiler-rt")
296      getDriver().Diag(clang::diag::err_drv_invalid_rtlib_name)
297          << A->getAsString(Args);
298  }
299
300  return ToolChain::RLT_CompilerRT;
301}
302
303ToolChain::CXXStdlibType
304Fuchsia::GetCXXStdlibType(const ArgList &Args) const {
305  if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) {
306    StringRef Value = A->getValue();
307    if (Value != "libc++")
308      getDriver().Diag(diag::err_drv_invalid_stdlib_name)
309        << A->getAsString(Args);
310  }
311
312  return ToolChain::CST_Libcxx;
313}
314
315void Fuchsia::addClangTargetOptions(const ArgList &DriverArgs,
316                                    ArgStringList &CC1Args,
317                                    Action::OffloadKind) const {
318  if (!DriverArgs.hasFlag(options::OPT_fuse_init_array,
319                          options::OPT_fno_use_init_array, true))
320    CC1Args.push_back("-fno-use-init-array");
321}
322
323void Fuchsia::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
324                                        ArgStringList &CC1Args) const {
325  const Driver &D = getDriver();
326
327  if (DriverArgs.hasArg(options::OPT_nostdinc))
328    return;
329
330  if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
331    SmallString<128> P(D.ResourceDir);
332    llvm::sys::path::append(P, "include");
333    addSystemInclude(DriverArgs, CC1Args, P);
334  }
335
336  if (DriverArgs.hasArg(options::OPT_nostdlibinc))
337    return;
338
339  // Check for configure-time C include directories.
340  StringRef CIncludeDirs(C_INCLUDE_DIRS);
341  if (CIncludeDirs != "") {
342    SmallVector<StringRef, 5> dirs;
343    CIncludeDirs.split(dirs, ":");
344    for (StringRef dir : dirs) {
345      StringRef Prefix =
346          llvm::sys::path::is_absolute(dir) ? "" : StringRef(D.SysRoot);
347      addExternCSystemInclude(DriverArgs, CC1Args, Prefix + dir);
348    }
349    return;
350  }
351
352  if (!D.SysRoot.empty()) {
353    SmallString<128> P(D.SysRoot);
354    llvm::sys::path::append(P, "include");
355    addExternCSystemInclude(DriverArgs, CC1Args, P.str());
356  }
357}
358
359void Fuchsia::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
360                                           ArgStringList &CC1Args) const {
361  if (DriverArgs.hasArg(options::OPT_nostdlibinc) ||
362      DriverArgs.hasArg(options::OPT_nostdincxx))
363    return;
364
365  const Driver &D = getDriver();
366  std::string Target = getTripleString();
367
368  auto AddCXXIncludePath = [&](StringRef Path) {
369    std::string Version = detectLibcxxVersion(Path);
370    if (Version.empty())
371      return;
372
373    // First add the per-target include path.
374    SmallString<128> TargetDir(Path);
375    llvm::sys::path::append(TargetDir, Target, "c++", Version);
376    if (getVFS().exists(TargetDir))
377      addSystemInclude(DriverArgs, CC1Args, TargetDir);
378
379    // Second add the generic one.
380    SmallString<128> Dir(Path);
381    llvm::sys::path::append(Dir, "c++", Version);
382    addSystemInclude(DriverArgs, CC1Args, Dir);
383  };
384
385  switch (GetCXXStdlibType(DriverArgs)) {
386  case ToolChain::CST_Libcxx: {
387    SmallString<128> P(D.Dir);
388    llvm::sys::path::append(P, "..", "include");
389    AddCXXIncludePath(P);
390    break;
391  }
392
393  default:
394    llvm_unreachable("invalid stdlib name");
395  }
396}
397
398void Fuchsia::AddCXXStdlibLibArgs(const ArgList &Args,
399                                  ArgStringList &CmdArgs) const {
400  switch (GetCXXStdlibType(Args)) {
401  case ToolChain::CST_Libcxx:
402    CmdArgs.push_back("-lc++");
403    break;
404
405  case ToolChain::CST_Libstdcxx:
406    llvm_unreachable("invalid stdlib name");
407  }
408}
409
410SanitizerMask Fuchsia::getSupportedSanitizers() const {
411  SanitizerMask Res = ToolChain::getSupportedSanitizers();
412  Res |= SanitizerKind::Address;
413  Res |= SanitizerKind::HWAddress;
414  Res |= SanitizerKind::PointerCompare;
415  Res |= SanitizerKind::PointerSubtract;
416  Res |= SanitizerKind::Fuzzer;
417  Res |= SanitizerKind::FuzzerNoLink;
418  Res |= SanitizerKind::Leak;
419  Res |= SanitizerKind::SafeStack;
420  Res |= SanitizerKind::Scudo;
421  Res |= SanitizerKind::Thread;
422  return Res;
423}
424
425SanitizerMask Fuchsia::getDefaultSanitizers() const {
426  SanitizerMask Res;
427  switch (getTriple().getArch()) {
428  case llvm::Triple::aarch64:
429    Res |= SanitizerKind::ShadowCallStack;
430    break;
431  case llvm::Triple::x86_64:
432    Res |= SanitizerKind::SafeStack;
433    break;
434  default:
435    // TODO: Enable SafeStack on RISC-V once tested.
436    break;
437  }
438  return Res;
439}
440
441void Fuchsia::addProfileRTLibs(const llvm::opt::ArgList &Args,
442                               llvm::opt::ArgStringList &CmdArgs) const {
443  // Add linker option -u__llvm_profile_runtime to cause runtime
444  // initialization module to be linked in.
445  if (needsProfileRT(Args))
446    CmdArgs.push_back(Args.MakeArgString(
447        Twine("-u", llvm::getInstrProfRuntimeHookVarName())));
448  ToolChain::addProfileRTLibs(Args, CmdArgs);
449}
450