xref: /freebsd/contrib/llvm-project/clang/lib/Driver/ToolChains/NaCl.cpp (revision 6580f5c38dd5b01aeeaed16b370f1a12423437f0)
1 //===--- NaCl.cpp - Native Client 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 "NaCl.h"
10 #include "CommonArgs.h"
11 #include "clang/Driver/Compilation.h"
12 #include "clang/Driver/Driver.h"
13 #include "clang/Driver/DriverDiagnostic.h"
14 #include "clang/Driver/InputInfo.h"
15 #include "clang/Driver/Options.h"
16 #include "llvm/Option/ArgList.h"
17 #include "llvm/Support/Path.h"
18 
19 using namespace clang::driver;
20 using namespace clang::driver::tools;
21 using namespace clang::driver::toolchains;
22 using namespace clang;
23 using namespace llvm::opt;
24 
25 // NaCl ARM assembly (inline or standalone) can be written with a set of macros
26 // for the various SFI requirements like register masking. The assembly tool
27 // inserts the file containing the macros as an input into all the assembly
28 // jobs.
29 void nacltools::AssemblerARM::ConstructJob(Compilation &C, const JobAction &JA,
30                                            const InputInfo &Output,
31                                            const InputInfoList &Inputs,
32                                            const ArgList &Args,
33                                            const char *LinkingOutput) const {
34   const auto &ToolChain = static_cast<const NaClToolChain &>(getToolChain());
35   InputInfo NaClMacros(types::TY_PP_Asm, ToolChain.GetNaClArmMacrosPath(),
36                        "nacl-arm-macros.s");
37   InputInfoList NewInputs;
38   NewInputs.push_back(NaClMacros);
39   NewInputs.append(Inputs.begin(), Inputs.end());
40   gnutools::Assembler::ConstructJob(C, JA, Output, NewInputs, Args,
41                                     LinkingOutput);
42 }
43 
44 // This is quite similar to gnutools::Linker::ConstructJob with changes that
45 // we use static by default, do not yet support sanitizers or LTO, and a few
46 // others. Eventually we can support more of that and hopefully migrate back
47 // to gnutools::Linker.
48 void nacltools::Linker::ConstructJob(Compilation &C, const JobAction &JA,
49                                      const InputInfo &Output,
50                                      const InputInfoList &Inputs,
51                                      const ArgList &Args,
52                                      const char *LinkingOutput) const {
53 
54   const auto &ToolChain = static_cast<const NaClToolChain &>(getToolChain());
55   const Driver &D = ToolChain.getDriver();
56   const llvm::Triple::ArchType Arch = ToolChain.getArch();
57   const bool IsStatic =
58       !Args.hasArg(options::OPT_dynamic) && !Args.hasArg(options::OPT_shared);
59 
60   ArgStringList CmdArgs;
61 
62   // Silence warning for "clang -g foo.o -o foo"
63   Args.ClaimAllArgs(options::OPT_g_Group);
64   // and "clang -emit-llvm foo.o -o foo"
65   Args.ClaimAllArgs(options::OPT_emit_llvm);
66   // and for "clang -w foo.o -o foo". Other warning options are already
67   // handled somewhere else.
68   Args.ClaimAllArgs(options::OPT_w);
69 
70   if (!D.SysRoot.empty())
71     CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
72 
73   if (Args.hasArg(options::OPT_rdynamic))
74     CmdArgs.push_back("-export-dynamic");
75 
76   if (Args.hasArg(options::OPT_s))
77     CmdArgs.push_back("-s");
78 
79   // NaClToolChain doesn't have ExtraOpts like Linux; the only relevant flag
80   // from there is --build-id, which we do want.
81   CmdArgs.push_back("--build-id");
82 
83   if (!IsStatic)
84     CmdArgs.push_back("--eh-frame-hdr");
85 
86   CmdArgs.push_back("-m");
87   if (Arch == llvm::Triple::x86)
88     CmdArgs.push_back("elf_i386_nacl");
89   else if (Arch == llvm::Triple::arm)
90     CmdArgs.push_back("armelf_nacl");
91   else if (Arch == llvm::Triple::x86_64)
92     CmdArgs.push_back("elf_x86_64_nacl");
93   else if (Arch == llvm::Triple::mipsel)
94     CmdArgs.push_back("mipselelf_nacl");
95   else
96     D.Diag(diag::err_target_unsupported_arch) << ToolChain.getArchName()
97                                               << "Native Client";
98 
99   if (IsStatic)
100     CmdArgs.push_back("-static");
101   else if (Args.hasArg(options::OPT_shared))
102     CmdArgs.push_back("-shared");
103 
104   CmdArgs.push_back("-o");
105   CmdArgs.push_back(Output.getFilename());
106   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
107     if (!Args.hasArg(options::OPT_shared))
108       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt1.o")));
109     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crti.o")));
110 
111     const char *crtbegin;
112     if (IsStatic)
113       crtbegin = "crtbeginT.o";
114     else if (Args.hasArg(options::OPT_shared))
115       crtbegin = "crtbeginS.o";
116     else
117       crtbegin = "crtbegin.o";
118     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtbegin)));
119   }
120 
121   Args.addAllArgs(CmdArgs, {options::OPT_L, options::OPT_u});
122 
123   ToolChain.AddFilePathLibArgs(Args, CmdArgs);
124 
125   if (Args.hasArg(options::OPT_Z_Xlinker__no_demangle))
126     CmdArgs.push_back("--no-demangle");
127 
128   AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
129 
130   if (D.CCCIsCXX() &&
131       !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
132     if (ToolChain.ShouldLinkCXXStdlib(Args)) {
133       bool OnlyLibstdcxxStatic =
134           Args.hasArg(options::OPT_static_libstdcxx) && !IsStatic;
135       if (OnlyLibstdcxxStatic)
136         CmdArgs.push_back("-Bstatic");
137       ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
138       if (OnlyLibstdcxxStatic)
139         CmdArgs.push_back("-Bdynamic");
140     }
141     CmdArgs.push_back("-lm");
142   }
143 
144   if (!Args.hasArg(options::OPT_nostdlib)) {
145     if (!Args.hasArg(options::OPT_nodefaultlibs)) {
146       // Always use groups, since it has no effect on dynamic libraries.
147       CmdArgs.push_back("--start-group");
148       CmdArgs.push_back("-lc");
149       // NaCl's libc++ currently requires libpthread, so just always include it
150       // in the group for C++.
151       if (Args.hasArg(options::OPT_pthread) ||
152           Args.hasArg(options::OPT_pthreads) || D.CCCIsCXX()) {
153         // Gold, used by Mips, handles nested groups differently than ld, and
154         // without '-lnacl' it prefers symbols from libpthread.a over libnacl.a,
155         // which is not a desired behaviour here.
156         // See https://sourceware.org/ml/binutils/2015-03/msg00034.html
157         if (getToolChain().getArch() == llvm::Triple::mipsel)
158           CmdArgs.push_back("-lnacl");
159 
160         CmdArgs.push_back("-lpthread");
161       }
162 
163       CmdArgs.push_back("-lgcc");
164       CmdArgs.push_back("--as-needed");
165       if (IsStatic)
166         CmdArgs.push_back("-lgcc_eh");
167       else
168         CmdArgs.push_back("-lgcc_s");
169       CmdArgs.push_back("--no-as-needed");
170 
171       // Mips needs to create and use pnacl_legacy library that contains
172       // definitions from bitcode/pnaclmm.c and definitions for
173       // __nacl_tp_tls_offset() and __nacl_tp_tdb_offset().
174       if (getToolChain().getArch() == llvm::Triple::mipsel)
175         CmdArgs.push_back("-lpnacl_legacy");
176 
177       CmdArgs.push_back("--end-group");
178     }
179 
180     if (!Args.hasArg(options::OPT_nostartfiles)) {
181       const char *crtend;
182       if (Args.hasArg(options::OPT_shared))
183         crtend = "crtendS.o";
184       else
185         crtend = "crtend.o";
186 
187       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtend)));
188       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
189     }
190   }
191 
192   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
193   C.addCommand(std::make_unique<Command>(JA, *this,
194                                          ResponseFileSupport::AtFileCurCP(),
195                                          Exec, CmdArgs, Inputs, Output));
196 }
197 
198 /// NaCl Toolchain
199 NaClToolChain::NaClToolChain(const Driver &D, const llvm::Triple &Triple,
200                              const ArgList &Args)
201     : Generic_ELF(D, Triple, Args) {
202 
203   // Remove paths added by Generic_GCC. NaCl Toolchain cannot use the
204   // default paths, and must instead only use the paths provided
205   // with this toolchain based on architecture.
206   path_list &file_paths = getFilePaths();
207   path_list &prog_paths = getProgramPaths();
208 
209   file_paths.clear();
210   prog_paths.clear();
211 
212   // Path for library files (libc.a, ...)
213   std::string FilePath(getDriver().Dir + "/../");
214 
215   // Path for tools (clang, ld, etc..)
216   std::string ProgPath(getDriver().Dir + "/../");
217 
218   // Path for toolchain libraries (libgcc.a, ...)
219   std::string ToolPath(getDriver().ResourceDir + "/lib/");
220 
221   switch (Triple.getArch()) {
222   case llvm::Triple::x86:
223     file_paths.push_back(FilePath + "x86_64-nacl/lib32");
224     file_paths.push_back(FilePath + "i686-nacl/usr/lib");
225     prog_paths.push_back(ProgPath + "x86_64-nacl/bin");
226     file_paths.push_back(ToolPath + "i686-nacl");
227     break;
228   case llvm::Triple::x86_64:
229     file_paths.push_back(FilePath + "x86_64-nacl/lib");
230     file_paths.push_back(FilePath + "x86_64-nacl/usr/lib");
231     prog_paths.push_back(ProgPath + "x86_64-nacl/bin");
232     file_paths.push_back(ToolPath + "x86_64-nacl");
233     break;
234   case llvm::Triple::arm:
235     file_paths.push_back(FilePath + "arm-nacl/lib");
236     file_paths.push_back(FilePath + "arm-nacl/usr/lib");
237     prog_paths.push_back(ProgPath + "arm-nacl/bin");
238     file_paths.push_back(ToolPath + "arm-nacl");
239     break;
240   case llvm::Triple::mipsel:
241     file_paths.push_back(FilePath + "mipsel-nacl/lib");
242     file_paths.push_back(FilePath + "mipsel-nacl/usr/lib");
243     prog_paths.push_back(ProgPath + "bin");
244     file_paths.push_back(ToolPath + "mipsel-nacl");
245     break;
246   default:
247     break;
248   }
249 
250   NaClArmMacrosPath = GetFilePath("nacl-arm-macros.s");
251 }
252 
253 void NaClToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
254                                               ArgStringList &CC1Args) const {
255   const Driver &D = getDriver();
256   if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc))
257     return;
258 
259   if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
260     SmallString<128> P(D.ResourceDir);
261     llvm::sys::path::append(P, "include");
262     addSystemInclude(DriverArgs, CC1Args, P.str());
263   }
264 
265   if (DriverArgs.hasArg(options::OPT_nostdlibinc))
266     return;
267 
268   SmallString<128> P(D.Dir + "/../");
269   switch (getTriple().getArch()) {
270   case llvm::Triple::x86:
271     // x86 is special because multilib style uses x86_64-nacl/include for libc
272     // headers but the SDK wants i686-nacl/usr/include. The other architectures
273     // have the same substring.
274     llvm::sys::path::append(P, "i686-nacl/usr/include");
275     addSystemInclude(DriverArgs, CC1Args, P.str());
276     llvm::sys::path::remove_filename(P);
277     llvm::sys::path::remove_filename(P);
278     llvm::sys::path::remove_filename(P);
279     llvm::sys::path::append(P, "x86_64-nacl/include");
280     addSystemInclude(DriverArgs, CC1Args, P.str());
281     return;
282   case llvm::Triple::arm:
283     llvm::sys::path::append(P, "arm-nacl/usr/include");
284     break;
285   case llvm::Triple::x86_64:
286     llvm::sys::path::append(P, "x86_64-nacl/usr/include");
287     break;
288   case llvm::Triple::mipsel:
289     llvm::sys::path::append(P, "mipsel-nacl/usr/include");
290     break;
291   default:
292     return;
293   }
294 
295   addSystemInclude(DriverArgs, CC1Args, P.str());
296   llvm::sys::path::remove_filename(P);
297   llvm::sys::path::remove_filename(P);
298   llvm::sys::path::append(P, "include");
299   addSystemInclude(DriverArgs, CC1Args, P.str());
300 }
301 
302 void NaClToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
303                                         ArgStringList &CmdArgs) const {
304   // Check for -stdlib= flags. We only support libc++ but this consumes the arg
305   // if the value is libc++, and emits an error for other values.
306   GetCXXStdlibType(Args);
307   CmdArgs.push_back("-lc++");
308   if (Args.hasArg(options::OPT_fexperimental_library))
309     CmdArgs.push_back("-lc++experimental");
310 }
311 
312 void NaClToolChain::addLibCxxIncludePaths(
313     const llvm::opt::ArgList &DriverArgs,
314     llvm::opt::ArgStringList &CC1Args) const {
315   const Driver &D = getDriver();
316 
317   SmallString<128> P(D.Dir + "/../");
318   switch (getTriple().getArch()) {
319   default:
320     break;
321   case llvm::Triple::arm:
322     llvm::sys::path::append(P, "arm-nacl/include/c++/v1");
323     addSystemInclude(DriverArgs, CC1Args, P.str());
324     break;
325   case llvm::Triple::x86:
326     llvm::sys::path::append(P, "x86_64-nacl/include/c++/v1");
327     addSystemInclude(DriverArgs, CC1Args, P.str());
328     break;
329   case llvm::Triple::x86_64:
330     llvm::sys::path::append(P, "x86_64-nacl/include/c++/v1");
331     addSystemInclude(DriverArgs, CC1Args, P.str());
332     break;
333   case llvm::Triple::mipsel:
334     llvm::sys::path::append(P, "mipsel-nacl/include/c++/v1");
335     addSystemInclude(DriverArgs, CC1Args, P.str());
336     break;
337   }
338 }
339 
340 ToolChain::CXXStdlibType
341 NaClToolChain::GetCXXStdlibType(const ArgList &Args) const {
342   if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) {
343     StringRef Value = A->getValue();
344     if (Value == "libc++")
345       return ToolChain::CST_Libcxx;
346     getDriver().Diag(clang::diag::err_drv_invalid_stdlib_name)
347         << A->getAsString(Args);
348   }
349 
350   return ToolChain::CST_Libcxx;
351 }
352 
353 std::string
354 NaClToolChain::ComputeEffectiveClangTriple(const ArgList &Args,
355                                            types::ID InputType) const {
356   llvm::Triple TheTriple(ComputeLLVMTriple(Args, InputType));
357   if (TheTriple.getArch() == llvm::Triple::arm &&
358       TheTriple.getEnvironment() == llvm::Triple::UnknownEnvironment)
359     TheTriple.setEnvironment(llvm::Triple::GNUEABIHF);
360   return TheTriple.getTriple();
361 }
362 
363 Tool *NaClToolChain::buildLinker() const {
364   return new tools::nacltools::Linker(*this);
365 }
366 
367 Tool *NaClToolChain::buildAssembler() const {
368   if (getTriple().getArch() == llvm::Triple::arm)
369     return new tools::nacltools::AssemblerARM(*this);
370   return new tools::gnutools::Assembler(*this);
371 }
372