Beispiel #1
0
//===----------------------------------------------------------------------===//
// main Driver function
//
int main(int argc, char **argv, char * const *envp) {
  sys::PrintStackTraceOnErrorSignal();
  PrettyStackTraceProgram X(argc, argv);

  LLVMContext &Context = getGlobalContext();
  atexit(do_shutdown);  // Call llvm_shutdown() on exit.

  // If we have a native target, initialize it to ensure it is linked in and
  // usable by the JIT.
  InitializeNativeTarget();
  InitializeNativeTargetAsmPrinter();
  InitializeNativeTargetAsmParser();

  cl::ParseCommandLineOptions(argc, argv,
                              "llvm interpreter & dynamic compiler\n");

  // If the user doesn't want core files, disable them.
  if (DisableCoreFiles)
    sys::Process::PreventCoreFiles();

  // Load the bitcode...
  SMDiagnostic Err;
  std::unique_ptr<Module> Owner = parseIRFile(InputFile, Err, Context);
  Module *Mod = Owner.get();
  if (!Mod) {
    Err.print(argv[0], errs());
    return 1;
  }

  if (UseJITKind == JITKind::OrcLazy)
    return runOrcLazyJIT(std::move(Owner), argc, argv);

  if (EnableCacheManager) {
    std::string CacheName("file:");
    CacheName.append(InputFile);
    Mod->setModuleIdentifier(CacheName);
  }

  // If not jitting lazily, load the whole bitcode file eagerly too.
  if (NoLazyCompilation) {
    if (std::error_code EC = Mod->materializeAll()) {
      errs() << argv[0] << ": bitcode didn't read correctly.\n";
      errs() << "Reason: " << EC.message() << "\n";
      exit(1);
    }
  }

  std::string ErrorMsg;
  EngineBuilder builder(std::move(Owner));
  builder.setMArch(MArch);
  builder.setMCPU(MCPU);
  builder.setMAttrs(MAttrs);
  builder.setRelocationModel(RelocModel);
  builder.setCodeModel(CMModel);
  builder.setErrorStr(&ErrorMsg);
  builder.setEngineKind(ForceInterpreter
                        ? EngineKind::Interpreter
                        : EngineKind::JIT);
  builder.setUseOrcMCJITReplacement(UseJITKind == JITKind::OrcMCJITReplacement);

  // If we are supposed to override the target triple, do so now.
  if (!TargetTriple.empty())
    Mod->setTargetTriple(Triple::normalize(TargetTriple));

  // Enable MCJIT if desired.
  RTDyldMemoryManager *RTDyldMM = nullptr;
  if (!ForceInterpreter) {
    if (RemoteMCJIT)
      RTDyldMM = new ForwardingMemoryManager();
    else
      RTDyldMM = new SectionMemoryManager();

    // Deliberately construct a temp std::unique_ptr to pass in. Do not null out
    // RTDyldMM: We still use it below, even though we don't own it.
    builder.setMCJITMemoryManager(
      std::unique_ptr<RTDyldMemoryManager>(RTDyldMM));
  } else if (RemoteMCJIT) {
    errs() << "error: Remote process execution does not work with the "
              "interpreter.\n";
    exit(1);
  }

  builder.setOptLevel(getOptLevel());

  TargetOptions Options;
  if (FloatABIForCalls != FloatABI::Default)
    Options.FloatABIType = FloatABIForCalls;

  builder.setTargetOptions(Options);

  EE = builder.create();
  if (!EE) {
    if (!ErrorMsg.empty())
      errs() << argv[0] << ": error creating EE: " << ErrorMsg << "\n";
    else
      errs() << argv[0] << ": unknown error creating EE!\n";
    exit(1);
  }

  if (EnableCacheManager) {
    CacheManager = new LLIObjectCache(ObjectCacheDir);
    EE->setObjectCache(CacheManager);
  }

  // Load any additional modules specified on the command line.
  for (unsigned i = 0, e = ExtraModules.size(); i != e; ++i) {
    std::unique_ptr<Module> XMod = parseIRFile(ExtraModules[i], Err, Context);
    if (!XMod) {
      Err.print(argv[0], errs());
      return 1;
    }
    if (EnableCacheManager) {
      std::string CacheName("file:");
      CacheName.append(ExtraModules[i]);
      XMod->setModuleIdentifier(CacheName);
    }
    EE->addModule(std::move(XMod));
  }

  for (unsigned i = 0, e = ExtraObjects.size(); i != e; ++i) {
    ErrorOr<object::OwningBinary<object::ObjectFile>> Obj =
        object::ObjectFile::createObjectFile(ExtraObjects[i]);
    if (!Obj) {
      Err.print(argv[0], errs());
      return 1;
    }
    object::OwningBinary<object::ObjectFile> &O = Obj.get();
    EE->addObjectFile(std::move(O));
  }

  for (unsigned i = 0, e = ExtraArchives.size(); i != e; ++i) {
    ErrorOr<std::unique_ptr<MemoryBuffer>> ArBufOrErr =
        MemoryBuffer::getFileOrSTDIN(ExtraArchives[i]);
    if (!ArBufOrErr) {
      Err.print(argv[0], errs());
      return 1;
    }
    std::unique_ptr<MemoryBuffer> &ArBuf = ArBufOrErr.get();

    ErrorOr<std::unique_ptr<object::Archive>> ArOrErr =
        object::Archive::create(ArBuf->getMemBufferRef());
    if (std::error_code EC = ArOrErr.getError()) {
      errs() << EC.message();
      return 1;
    }
    std::unique_ptr<object::Archive> &Ar = ArOrErr.get();

    object::OwningBinary<object::Archive> OB(std::move(Ar), std::move(ArBuf));

    EE->addArchive(std::move(OB));
  }

  // If the target is Cygwin/MingW and we are generating remote code, we
  // need an extra module to help out with linking.
  if (RemoteMCJIT && Triple(Mod->getTargetTriple()).isOSCygMing()) {
    addCygMingExtraModule(EE, Context, Mod->getTargetTriple());
  }

  // The following functions have no effect if their respective profiling
  // support wasn't enabled in the build configuration.
  EE->RegisterJITEventListener(
                JITEventListener::createOProfileJITEventListener());
  EE->RegisterJITEventListener(
                JITEventListener::createIntelJITEventListener());

  if (!NoLazyCompilation && RemoteMCJIT) {
    errs() << "warning: remote mcjit does not support lazy compilation\n";
    NoLazyCompilation = true;
  }
  EE->DisableLazyCompilation(NoLazyCompilation);

  // If the user specifically requested an argv[0] to pass into the program,
  // do it now.
  if (!FakeArgv0.empty()) {
    InputFile = static_cast<std::string>(FakeArgv0);
  } else {
    // Otherwise, if there is a .bc suffix on the executable strip it off, it
    // might confuse the program.
    if (StringRef(InputFile).endswith(".bc"))
      InputFile.erase(InputFile.length() - 3);
  }

  // Add the module's name to the start of the vector of arguments to main().
  InputArgv.insert(InputArgv.begin(), InputFile);

  // Call the main function from M as if its signature were:
  //   int main (int argc, char **argv, const char **envp)
  // using the contents of Args to determine argc & argv, and the contents of
  // EnvVars to determine envp.
  //
  Function *EntryFn = Mod->getFunction(EntryFunc);
  if (!EntryFn) {
    errs() << '\'' << EntryFunc << "\' function not found in module.\n";
    return -1;
  }

  // Reset errno to zero on entry to main.
  errno = 0;

  int Result;

  // Sanity check use of remote-jit: LLI currently only supports use of the
  // remote JIT on Unix platforms.
  if (RemoteMCJIT) {
#ifndef LLVM_ON_UNIX
    errs() << "Warning: host does not support external remote targets.\n"
           << "  Defaulting to local execution execution\n";
    return -1;
#else
    if (ChildExecPath.empty()) {
      errs() << "-remote-mcjit requires -mcjit-remote-process.\n";
      exit(1);
    } else if (!sys::fs::can_execute(ChildExecPath)) {
      errs() << "Unable to find usable child executable: '" << ChildExecPath
             << "'\n";
      return -1;
    }
#endif
  }

  if (!RemoteMCJIT) {
    // If the program doesn't explicitly call exit, we will need the Exit
    // function later on to make an explicit call, so get the function now.
    Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context),
                                                      Type::getInt32Ty(Context),
                                                      nullptr);

    // Run static constructors.
    if (!ForceInterpreter) {
      // Give MCJIT a chance to apply relocations and set page permissions.
      EE->finalizeObject();
    }
    EE->runStaticConstructorsDestructors(false);

    // Trigger compilation separately so code regions that need to be
    // invalidated will be known.
    (void)EE->getPointerToFunction(EntryFn);
    // Clear instruction cache before code will be executed.
    if (RTDyldMM)
      static_cast<SectionMemoryManager*>(RTDyldMM)->invalidateInstructionCache();

    // Run main.
    Result = EE->runFunctionAsMain(EntryFn, InputArgv, envp);

    // Run static destructors.
    EE->runStaticConstructorsDestructors(true);

    // If the program didn't call exit explicitly, we should call it now.
    // This ensures that any atexit handlers get called correctly.
    if (Function *ExitF = dyn_cast<Function>(Exit)) {
      std::vector<GenericValue> Args;
      GenericValue ResultGV;
      ResultGV.IntVal = APInt(32, Result);
      Args.push_back(ResultGV);
      EE->runFunction(ExitF, Args);
      errs() << "ERROR: exit(" << Result << ") returned!\n";
      abort();
    } else {
      errs() << "ERROR: exit defined with wrong prototype!\n";
      abort();
    }
  } else {
    // else == "if (RemoteMCJIT)"

    // Remote target MCJIT doesn't (yet) support static constructors. No reason
    // it couldn't. This is a limitation of the LLI implemantation, not the
    // MCJIT itself. FIXME.

    // Lanch the remote process and get a channel to it.
    std::unique_ptr<FDRPCChannel> C = launchRemote();
    if (!C) {
      errs() << "Failed to launch remote JIT.\n";
      exit(1);
    }

    // Create a remote target client running over the channel.
    typedef orc::remote::OrcRemoteTargetClient<orc::remote::RPCChannel> MyRemote;
    ErrorOr<MyRemote> R = MyRemote::Create(*C);
    if (!R) {
      errs() << "Could not create remote: " << R.getError().message() << "\n";
      exit(1);
    }

    // Create a remote memory manager.
    std::unique_ptr<MyRemote::RCMemoryManager> RemoteMM;
    if (auto EC = R->createRemoteMemoryManager(RemoteMM)) {
      errs() << "Could not create remote memory manager: " << EC.message() << "\n";
      exit(1);
    }

    // Forward MCJIT's memory manager calls to the remote memory manager.
    static_cast<ForwardingMemoryManager*>(RTDyldMM)->setMemMgr(
      std::move(RemoteMM));

    // Forward MCJIT's symbol resolution calls to the remote.
    static_cast<ForwardingMemoryManager*>(RTDyldMM)->setResolver(
      orc::createLambdaResolver(
        [&](const std::string &Name) {
          orc::TargetAddress Addr = 0;
          if (auto EC = R->getSymbolAddress(Addr, Name)) {
            errs() << "Failure during symbol lookup: " << EC.message() << "\n";
            exit(1);
          }
          return RuntimeDyld::SymbolInfo(Addr, JITSymbolFlags::Exported);
        },
        [](const std::string &Name) { return nullptr; }
      ));

    // Grab the target address of the JIT'd main function on the remote and call
    // it.
    // FIXME: argv and envp handling.
    orc::TargetAddress Entry = EE->getFunctionAddress(EntryFn->getName().str());
    EE->finalizeObject();
    DEBUG(dbgs() << "Executing '" << EntryFn->getName() << "' at 0x"
                 << format("%llx", Entry) << "\n");
    if (auto EC = R->callIntVoid(Result, Entry))
      errs() << "ERROR: " << EC.message() << "\n";

    // Like static constructors, the remote target MCJIT support doesn't handle
    // this yet. It could. FIXME.

    // Delete the EE - we need to tear it down *before* we terminate the session
    // with the remote, otherwise it'll crash when it tries to release resources
    // on a remote that has already been disconnected.
    delete EE;
    EE = nullptr;

    // Signal the remote target that we're done JITing.
    R->terminateSession();
  }

  return Result;
}