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/Support/FileSystem.h"
19#include "llvm/Support/Path.h"
20#include "llvm/Support/VirtualFileSystem.h"
21
22using namespace clang::driver;
23using namespace clang::driver::toolchains;
24using namespace clang::driver::tools;
25using namespace clang;
26using namespace llvm::opt;
27
28using tools::addMultilibFlag;
29
30void fuchsia::Linker::ConstructJob(Compilation &C, const JobAction &JA,
31                                   const InputInfo &Output,
32                                   const InputInfoList &Inputs,
33                                   const ArgList &Args,
34                                   const char *LinkingOutput) const {
35  const toolchains::Fuchsia &ToolChain =
36      static_cast<const toolchains::Fuchsia &>(getToolChain());
37  const Driver &D = ToolChain.getDriver();
38
39  ArgStringList CmdArgs;
40
41  // Silence warning for "clang -g foo.o -o foo"
42  Args.ClaimAllArgs(options::OPT_g_Group);
43  // and "clang -emit-llvm foo.o -o foo"
44  Args.ClaimAllArgs(options::OPT_emit_llvm);
45  // and for "clang -w foo.o -o foo". Other warning options are already
46  // handled somewhere else.
47  Args.ClaimAllArgs(options::OPT_w);
48
49  CmdArgs.push_back("-z");
50  CmdArgs.push_back("now");
51
52  const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
53  if (llvm::sys::path::filename(Exec).equals_lower("ld.lld") ||
54      llvm::sys::path::stem(Exec).equals_lower("ld.lld")) {
55    CmdArgs.push_back("-z");
56    CmdArgs.push_back("rodynamic");
57    CmdArgs.push_back("-z");
58    CmdArgs.push_back("separate-loadable-segments");
59  }
60
61  if (!D.SysRoot.empty())
62    CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
63
64  if (!Args.hasArg(options::OPT_shared) && !Args.hasArg(options::OPT_r))
65    CmdArgs.push_back("-pie");
66
67  if (Args.hasArg(options::OPT_rdynamic))
68    CmdArgs.push_back("-export-dynamic");
69
70  if (Args.hasArg(options::OPT_s))
71    CmdArgs.push_back("-s");
72
73  if (Args.hasArg(options::OPT_r)) {
74    CmdArgs.push_back("-r");
75  } else {
76    CmdArgs.push_back("--build-id");
77    CmdArgs.push_back("--hash-style=gnu");
78  }
79
80  CmdArgs.push_back("--eh-frame-hdr");
81
82  if (Args.hasArg(options::OPT_static))
83    CmdArgs.push_back("-Bstatic");
84  else if (Args.hasArg(options::OPT_shared))
85    CmdArgs.push_back("-shared");
86
87  const SanitizerArgs &SanArgs = ToolChain.getSanitizerArgs();
88
89  if (!Args.hasArg(options::OPT_shared)) {
90    std::string Dyld = D.DyldPrefix;
91    if (SanArgs.needsAsanRt() && SanArgs.needsSharedRt())
92      Dyld += "asan/";
93    Dyld += "ld.so.1";
94    CmdArgs.push_back("-dynamic-linker");
95    CmdArgs.push_back(Args.MakeArgString(Dyld));
96  }
97
98  CmdArgs.push_back("-o");
99  CmdArgs.push_back(Output.getFilename());
100
101  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
102    if (!Args.hasArg(options::OPT_shared)) {
103      CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("Scrt1.o")));
104    }
105  }
106
107  Args.AddAllArgs(CmdArgs, options::OPT_L);
108  Args.AddAllArgs(CmdArgs, options::OPT_u);
109
110  ToolChain.AddFilePathLibArgs(Args, CmdArgs);
111
112  if (D.isUsingLTO()) {
113    assert(!Inputs.empty() && "Must have at least one input.");
114    AddGoldPlugin(ToolChain, Args, CmdArgs, Output, Inputs[0],
115                  D.getLTOMode() == LTOK_Thin);
116  }
117
118  bool NeedsSanitizerDeps = addSanitizerRuntimes(ToolChain, Args, CmdArgs);
119  bool NeedsXRayDeps = addXRayRuntime(ToolChain, Args, CmdArgs);
120  AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
121  ToolChain.addProfileRTLibs(Args, CmdArgs);
122
123  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
124    if (Args.hasArg(options::OPT_static))
125      CmdArgs.push_back("-Bdynamic");
126
127    if (D.CCCIsCXX()) {
128      if (ToolChain.ShouldLinkCXXStdlib(Args)) {
129        bool OnlyLibstdcxxStatic = Args.hasArg(options::OPT_static_libstdcxx) &&
130                                   !Args.hasArg(options::OPT_static);
131        CmdArgs.push_back("--push-state");
132        CmdArgs.push_back("--as-needed");
133        if (OnlyLibstdcxxStatic)
134          CmdArgs.push_back("-Bstatic");
135        ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
136        if (OnlyLibstdcxxStatic)
137          CmdArgs.push_back("-Bdynamic");
138        CmdArgs.push_back("-lm");
139        CmdArgs.push_back("--pop-state");
140      }
141    }
142
143    if (NeedsSanitizerDeps)
144      linkSanitizerRuntimeDeps(ToolChain, CmdArgs);
145
146    if (NeedsXRayDeps)
147      linkXRayRuntimeDeps(ToolChain, CmdArgs);
148
149    AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
150
151    if (Args.hasArg(options::OPT_pthread) ||
152        Args.hasArg(options::OPT_pthreads))
153      CmdArgs.push_back("-lpthread");
154
155    if (Args.hasArg(options::OPT_fsplit_stack))
156      CmdArgs.push_back("--wrap=pthread_create");
157
158    if (!Args.hasArg(options::OPT_nolibc))
159      CmdArgs.push_back("-lc");
160  }
161
162  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
163}
164
165/// Fuchsia - Fuchsia tool chain which can call as(1) and ld(1) directly.
166
167Fuchsia::Fuchsia(const Driver &D, const llvm::Triple &Triple,
168                 const ArgList &Args)
169    : ToolChain(D, Triple, Args) {
170  getProgramPaths().push_back(getDriver().getInstalledDir());
171  if (getDriver().getInstalledDir() != D.Dir)
172    getProgramPaths().push_back(D.Dir);
173
174  if (!D.SysRoot.empty()) {
175    SmallString<128> P(D.SysRoot);
176    llvm::sys::path::append(P, "lib");
177    getFilePaths().push_back(P.str());
178  }
179
180  auto FilePaths = [&](const Multilib &M) -> std::vector<std::string> {
181    std::vector<std::string> FP;
182    if (D.CCCIsCXX()) {
183      if (auto CXXStdlibPath = getCXXStdlibPath()) {
184        SmallString<128> P(*CXXStdlibPath);
185        llvm::sys::path::append(P, M.gccSuffix());
186        FP.push_back(P.str());
187      }
188    }
189    return FP;
190  };
191
192  Multilibs.push_back(Multilib());
193  // Use the noexcept variant with -fno-exceptions to avoid the extra overhead.
194  Multilibs.push_back(Multilib("noexcept", {}, {}, 1)
195                          .flag("-fexceptions")
196                          .flag("+fno-exceptions"));
197  // ASan has higher priority because we always want the instrumentated version.
198  Multilibs.push_back(Multilib("asan", {}, {}, 2)
199                          .flag("+fsanitize=address"));
200  // Use the asan+noexcept variant with ASan and -fno-exceptions.
201  Multilibs.push_back(Multilib("asan+noexcept", {}, {}, 3)
202                          .flag("+fsanitize=address")
203                          .flag("-fexceptions")
204                          .flag("+fno-exceptions"));
205  Multilibs.FilterOut([&](const Multilib &M) {
206    std::vector<std::string> RD = FilePaths(M);
207    return std::all_of(RD.begin(), RD.end(), [&](std::string P) {
208      return !getVFS().exists(P);
209    });
210  });
211
212  Multilib::flags_list Flags;
213  addMultilibFlag(
214      Args.hasFlag(options::OPT_fexceptions, options::OPT_fno_exceptions, true),
215      "fexceptions", Flags);
216  addMultilibFlag(getSanitizerArgs().needsAsanRt(), "fsanitize=address", Flags);
217  Multilibs.setFilePathsCallback(FilePaths);
218
219  if (Multilibs.select(Flags, SelectedMultilib))
220    if (!SelectedMultilib.isDefault())
221      if (const auto &PathsCallback = Multilibs.filePathsCallback())
222        for (const auto &Path : PathsCallback(SelectedMultilib))
223          // Prepend the multilib path to ensure it takes the precedence.
224          getFilePaths().insert(getFilePaths().begin(), Path);
225}
226
227std::string Fuchsia::ComputeEffectiveClangTriple(const ArgList &Args,
228                                                 types::ID InputType) const {
229  llvm::Triple Triple(ComputeLLVMTriple(Args, InputType));
230  return Triple.str();
231}
232
233Tool *Fuchsia::buildLinker() const {
234  return new tools::fuchsia::Linker(*this);
235}
236
237ToolChain::RuntimeLibType Fuchsia::GetRuntimeLibType(
238    const ArgList &Args) const {
239  if (Arg *A = Args.getLastArg(clang::driver::options::OPT_rtlib_EQ)) {
240    StringRef Value = A->getValue();
241    if (Value != "compiler-rt")
242      getDriver().Diag(clang::diag::err_drv_invalid_rtlib_name)
243          << A->getAsString(Args);
244  }
245
246  return ToolChain::RLT_CompilerRT;
247}
248
249ToolChain::CXXStdlibType
250Fuchsia::GetCXXStdlibType(const ArgList &Args) const {
251  if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) {
252    StringRef Value = A->getValue();
253    if (Value != "libc++")
254      getDriver().Diag(diag::err_drv_invalid_stdlib_name)
255        << A->getAsString(Args);
256  }
257
258  return ToolChain::CST_Libcxx;
259}
260
261void Fuchsia::addClangTargetOptions(const ArgList &DriverArgs,
262                                    ArgStringList &CC1Args,
263                                    Action::OffloadKind) const {
264  if (!DriverArgs.hasFlag(options::OPT_fuse_init_array,
265                          options::OPT_fno_use_init_array, true))
266    CC1Args.push_back("-fno-use-init-array");
267}
268
269void Fuchsia::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
270                                        ArgStringList &CC1Args) const {
271  const Driver &D = getDriver();
272
273  if (DriverArgs.hasArg(options::OPT_nostdinc))
274    return;
275
276  if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
277    SmallString<128> P(D.ResourceDir);
278    llvm::sys::path::append(P, "include");
279    addSystemInclude(DriverArgs, CC1Args, P);
280  }
281
282  if (DriverArgs.hasArg(options::OPT_nostdlibinc))
283    return;
284
285  // Check for configure-time C include directories.
286  StringRef CIncludeDirs(C_INCLUDE_DIRS);
287  if (CIncludeDirs != "") {
288    SmallVector<StringRef, 5> dirs;
289    CIncludeDirs.split(dirs, ":");
290    for (StringRef dir : dirs) {
291      StringRef Prefix =
292          llvm::sys::path::is_absolute(dir) ? StringRef(D.SysRoot) : "";
293      addExternCSystemInclude(DriverArgs, CC1Args, Prefix + dir);
294    }
295    return;
296  }
297
298  if (!D.SysRoot.empty()) {
299    SmallString<128> P(D.SysRoot);
300    llvm::sys::path::append(P, "include");
301    addExternCSystemInclude(DriverArgs, CC1Args, P.str());
302  }
303}
304
305void Fuchsia::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
306                                           ArgStringList &CC1Args) const {
307  if (DriverArgs.hasArg(options::OPT_nostdlibinc) ||
308      DriverArgs.hasArg(options::OPT_nostdincxx))
309    return;
310
311  switch (GetCXXStdlibType(DriverArgs)) {
312  case ToolChain::CST_Libcxx: {
313    SmallString<128> P(getDriver().Dir);
314    llvm::sys::path::append(P, "..", "include", "c++", "v1");
315    addSystemInclude(DriverArgs, CC1Args, P.str());
316    break;
317  }
318
319  default:
320    llvm_unreachable("invalid stdlib name");
321  }
322}
323
324void Fuchsia::AddCXXStdlibLibArgs(const ArgList &Args,
325                                  ArgStringList &CmdArgs) const {
326  switch (GetCXXStdlibType(Args)) {
327  case ToolChain::CST_Libcxx:
328    CmdArgs.push_back("-lc++");
329    break;
330
331  case ToolChain::CST_Libstdcxx:
332    llvm_unreachable("invalid stdlib name");
333  }
334}
335
336SanitizerMask Fuchsia::getSupportedSanitizers() const {
337  SanitizerMask Res = ToolChain::getSupportedSanitizers();
338  Res |= SanitizerKind::Address;
339  Res |= SanitizerKind::PointerCompare;
340  Res |= SanitizerKind::PointerSubtract;
341  Res |= SanitizerKind::Fuzzer;
342  Res |= SanitizerKind::FuzzerNoLink;
343  Res |= SanitizerKind::SafeStack;
344  Res |= SanitizerKind::Scudo;
345  return Res;
346}
347
348SanitizerMask Fuchsia::getDefaultSanitizers() const {
349  SanitizerMask Res;
350  switch (getTriple().getArch()) {
351  case llvm::Triple::aarch64:
352    Res |= SanitizerKind::ShadowCallStack;
353    break;
354  case llvm::Triple::x86_64:
355    Res |= SanitizerKind::SafeStack;
356    break;
357  default:
358    // TODO: Enable SafeStack on RISC-V once tested.
359    break;
360  }
361  return Res;
362}
363