tools/lli/lli.cpp

   1 //===- lli.cpp - LLVM Interpreter / Dynamic compiler ----------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This utility provides a simple wrapper around the LLVM Execution Engines,
  11 // which allow the direct execution of LLVM programs through a Just-In-Time
  12 // compiler, or through an interpreter if no JIT is available for this platform.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #include "RemoteJITUtils.h"
  17 #include "llvm/ADT/StringExtras.h"
  18 #include "llvm/ADT/Triple.h"
  19 #include "llvm/Bitcode/BitcodeReader.h"
  20 #include "llvm/CodeGen/CommandFlags.inc"
  21 #include "llvm/CodeGen/LinkAllCodegenComponents.h"
  22 #include "llvm/Config/llvm-config.h"
  23 #include "llvm/ExecutionEngine/GenericValue.h"
  24 #include "llvm/ExecutionEngine/Interpreter.h"
  25 #include "llvm/ExecutionEngine/JITEventListener.h"
  26 #include "llvm/ExecutionEngine/MCJIT.h"
  27 #include "llvm/ExecutionEngine/ObjectCache.h"
  28 #include "llvm/ExecutionEngine/Orc/ExecutionUtils.h"
  29 #include "llvm/ExecutionEngine/Orc/LLJIT.h"
  30 #include "llvm/ExecutionEngine/Orc/OrcRemoteTargetClient.h"
  31 #include "llvm/ExecutionEngine/OrcMCJITReplacement.h"
  32 #include "llvm/ExecutionEngine/SectionMemoryManager.h"
  33 #include "llvm/IR/IRBuilder.h"
  34 #include "llvm/IR/LLVMContext.h"
  35 #include "llvm/IR/Module.h"
  36 #include "llvm/IR/Type.h"
  37 #include "llvm/IR/TypeBuilder.h"
  38 #include "llvm/IR/Verifier.h"
  39 #include "llvm/IRReader/IRReader.h"
  40 #include "llvm/Object/Archive.h"
  41 #include "llvm/Object/ObjectFile.h"
  42 #include "llvm/Support/CommandLine.h"
  43 #include "llvm/Support/Debug.h"
  44 #include "llvm/Support/DynamicLibrary.h"
  45 #include "llvm/Support/Format.h"
  46 #include "llvm/Support/InitLLVM.h"
  47 #include "llvm/Support/ManagedStatic.h"
  48 #include "llvm/Support/MathExtras.h"
  49 #include "llvm/Support/Memory.h"
  50 #include "llvm/Support/MemoryBuffer.h"
  51 #include "llvm/Support/Path.h"
  52 #include "llvm/Support/PluginLoader.h"
  53 #include "llvm/Support/Process.h"
  54 #include "llvm/Support/Program.h"
  55 #include "llvm/Support/SourceMgr.h"
  56 #include "llvm/Support/TargetSelect.h"
  57 #include "llvm/Support/WithColor.h"
  58 #include "llvm/Support/raw_ostream.h"
  59 #include "llvm/Transforms/Instrumentation.h"
  60 #include <cerrno>
  61
  62 #ifdef __CYGWIN__
  63 #include <cygwin/version.h>
  64 #if defined(CYGWIN_VERSION_DLL_MAJOR) && CYGWIN_VERSION_DLL_MAJOR<1007
  65 #define DO_NOTHING_ATEXIT 1
  66 #endif
  67 #endif
  68
  69 using namespace llvm;
  70
  71 #define DEBUG_TYPE "lli"
  72
  73 namespace {
  74
  75   enum class JITKind { MCJIT, OrcMCJITReplacement, OrcLazy };
  76
  77   cl::opt<std::string>
  78   InputFile(cl::desc("<input bitcode>"), cl::Positional, cl::init("-"));
  79
  80   cl::list<std::string>
  81   InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>..."));
  82
  83   cl::opt<bool> ForceInterpreter("force-interpreter",
  84                                  cl::desc("Force interpretation: disable JIT"),
  85                                  cl::init(false));
  86
  87   cl::opt<JITKind> UseJITKind("jit-kind",
  88                               cl::desc("Choose underlying JIT kind."),
  89                               cl::init(JITKind::MCJIT),
  90                               cl::values(
  91                                 clEnumValN(JITKind::MCJIT, "mcjit",
  92                                            "MCJIT"),
  93                                 clEnumValN(JITKind::OrcMCJITReplacement,
  94                                            "orc-mcjit",
  95                                            "Orc-based MCJIT replacement"),
  96                                 clEnumValN(JITKind::OrcLazy,
  97                                            "orc-lazy",
  98                                            "Orc-based lazy JIT.")));
  99
 100   // The MCJIT supports building for a target address space separate from
 101   // the JIT compilation process. Use a forked process and a copying
 102   // memory manager with IPC to execute using this functionality.
 103   cl::opt<bool> RemoteMCJIT("remote-mcjit",
 104     cl::desc("Execute MCJIT'ed code in a separate process."),
 105     cl::init(false));
 106
 107   // Manually specify the child process for remote execution. This overrides
 108   // the simulated remote execution that allocates address space for child
 109   // execution. The child process will be executed and will communicate with
 110   // lli via stdin/stdout pipes.
 111   cl::opt<std::string>
 112   ChildExecPath("mcjit-remote-process",
 113                 cl::desc("Specify the filename of the process to launch "
 114                          "for remote MCJIT execution.  If none is specified,"
 115                          "\n\tremote execution will be simulated in-process."),
 116                 cl::value_desc("filename"), cl::init(""));
 117
 118   // Determine optimization level.
 119   cl::opt<char>
 120   OptLevel("O",
 121            cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
 122                     "(default = '-O2')"),
 123            cl::Prefix,
 124            cl::ZeroOrMore,
 125            cl::init(' '));
 126
 127   cl::opt<std::string>
 128   TargetTriple("mtriple", cl::desc("Override target triple for module"));
 129
 130   cl::opt<std::string>
 131   EntryFunc("entry-function",
 132             cl::desc("Specify the entry function (default = 'main') "
 133                      "of the executable"),
 134             cl::value_desc("function"),
 135             cl::init("main"));
 136
 137   cl::list<std::string>
 138   ExtraModules("extra-module",
 139          cl::desc("Extra modules to be loaded"),
 140          cl::value_desc("input bitcode"));
 141
 142   cl::list<std::string>
 143   ExtraObjects("extra-object",
 144          cl::desc("Extra object files to be loaded"),
 145          cl::value_desc("input object"));
 146
 147   cl::list<std::string>
 148   ExtraArchives("extra-archive",
 149          cl::desc("Extra archive files to be loaded"),
 150          cl::value_desc("input archive"));
 151
 152   cl::opt<bool>
 153   EnableCacheManager("enable-cache-manager",
 154         cl::desc("Use cache manager to save/load mdoules"),
 155         cl::init(false));
 156
 157   cl::opt<std::string>
 158   ObjectCacheDir("object-cache-dir",
 159                   cl::desc("Directory to store cached object files "
 160                            "(must be user writable)"),
 161                   cl::init(""));
 162
 163   cl::opt<std::string>
 164   FakeArgv0("fake-argv0",
 165             cl::desc("Override the 'argv[0]' value passed into the executing"
 166                      " program"), cl::value_desc("executable"));
 167
 168   cl::opt<bool>
 169   DisableCoreFiles("disable-core-files", cl::Hidden,
 170                    cl::desc("Disable emission of core files if possible"));
 171
 172   cl::opt<bool>
 173   NoLazyCompilation("disable-lazy-compilation",
 174                   cl::desc("Disable JIT lazy compilation"),
 175                   cl::init(false));
 176
 177   cl::opt<bool>
 178   GenerateSoftFloatCalls("soft-float",
 179     cl::desc("Generate software floating point library calls"),
 180     cl::init(false));
 181
 182   enum class DumpKind {
 183     NoDump,
 184     DumpFuncsToStdOut,
 185     DumpModsToStdOut,
 186     DumpModsToDisk
 187   };
 188
 189   cl::opt<DumpKind> OrcDumpKind(
 190       "orc-lazy-debug", cl::desc("Debug dumping for the orc-lazy JIT."),
 191       cl::init(DumpKind::NoDump),
 192       cl::values(clEnumValN(DumpKind::NoDump, "no-dump",
 193                             "Don't dump anything."),
 194                  clEnumValN(DumpKind::DumpFuncsToStdOut, "funcs-to-stdout",
 195                             "Dump function names to stdout."),
 196                  clEnumValN(DumpKind::DumpModsToStdOut, "mods-to-stdout",
 197                             "Dump modules to stdout."),
 198                  clEnumValN(DumpKind::DumpModsToDisk, "mods-to-disk",
 199                             "Dump modules to the current "
 200                             "working directory. (WARNING: "
 201                             "will overwrite existing files).")),
 202       cl::Hidden);
 203
 204   ExitOnError ExitOnErr;
 205 }
 206
 207 //===----------------------------------------------------------------------===//
 208 // Object cache
 209 //
 210 // This object cache implementation writes cached objects to disk to the
 211 // directory specified by CacheDir, using a filename provided in the module
 212 // descriptor. The cache tries to load a saved object using that path if the
 213 // file exists. CacheDir defaults to "", in which case objects are cached
 214 // alongside their originating bitcodes.
 215 //
 216 class LLIObjectCache : public ObjectCache {
 217 public:
 218   LLIObjectCache(const std::string& CacheDir) : CacheDir(CacheDir) {
 219     // Add trailing '/' to cache dir if necessary.
 220     if (!this->CacheDir.empty() &&
 221         this->CacheDir[this->CacheDir.size() - 1] != '/')
 222       this->CacheDir += '/';
 223   }
 224   ~LLIObjectCache() override {}
 225
 226   void notifyObjectCompiled(const Module *M, MemoryBufferRef Obj) override {
 227     const std::string &ModuleID = M->getModuleIdentifier();
 228     std::string CacheName;
 229     if (!getCacheFilename(ModuleID, CacheName))
 230       return;
 231     if (!CacheDir.empty()) { // Create user-defined cache dir.
 232       SmallString<128> dir(sys::path::parent_path(CacheName));
 233       sys::fs::create_directories(Twine(dir));
 234     }
 235     std::error_code EC;
 236     raw_fd_ostream outfile(CacheName, EC, sys::fs::F_None);
 237     outfile.write(Obj.getBufferStart(), Obj.getBufferSize());
 238     outfile.close();
 239   }
 240
 241   std::unique_ptr<MemoryBuffer> getObject(const Module* M) override {
 242     const std::string &ModuleID = M->getModuleIdentifier();
 243     std::string CacheName;
 244     if (!getCacheFilename(ModuleID, CacheName))
 245       return nullptr;
 246     // Load the object from the cache filename
 247     ErrorOr<std::unique_ptr<MemoryBuffer>> IRObjectBuffer =
 248         MemoryBuffer::getFile(CacheName, -1, false);
 249     // If the file isn't there, that's OK.
 250     if (!IRObjectBuffer)
 251       return nullptr;
 252     // MCJIT will want to write into this buffer, and we don't want that
 253     // because the file has probably just been mmapped.  Instead we make
 254     // a copy.  The filed-based buffer will be released when it goes
 255     // out of scope.
 256     return MemoryBuffer::getMemBufferCopy(IRObjectBuffer.get()->getBuffer());
 257   }
 258
 259 private:
 260   std::string CacheDir;
 261
 262   bool getCacheFilename(const std::string &ModID, std::string &CacheName) {
 263     std::string Prefix("file:");
 264     size_t PrefixLength = Prefix.length();
 265     if (ModID.substr(0, PrefixLength) != Prefix)
 266       return false;
 267         std::string CacheSubdir = ModID.substr(PrefixLength);
 268 #if defined(_WIN32)
 269         // Transform "X:\foo" => "/X\foo" for convenience.
 270         if (isalpha(CacheSubdir[0]) && CacheSubdir[1] == ':') {
 271           CacheSubdir[1] = CacheSubdir[0];
 272           CacheSubdir[0] = '/';
 273         }
 274 #endif
 275     CacheName = CacheDir + CacheSubdir;
 276     size_t pos = CacheName.rfind('.');
 277     CacheName.replace(pos, CacheName.length() - pos, ".o");
 278     return true;
 279   }
 280 };
 281
 282 // On Mingw and Cygwin, an external symbol named '__main' is called from the
 283 // generated 'main' function to allow static initialization.  To avoid linking
 284 // problems with remote targets (because lli's remote target support does not
 285 // currently handle external linking) we add a secondary module which defines
 286 // an empty '__main' function.
 287 static void addCygMingExtraModule(ExecutionEngine &EE, LLVMContext &Context,
 288                                   StringRef TargetTripleStr) {
 289   IRBuilder<> Builder(Context);
 290   Triple TargetTriple(TargetTripleStr);
 291
 292   // Create a new module.
 293   std::unique_ptr<Module> M = make_unique<Module>("CygMingHelper", Context);
 294   M->setTargetTriple(TargetTripleStr);
 295
 296   // Create an empty function named "__main".
 297   Function *Result;
 298   if (TargetTriple.isArch64Bit()) {
 299     Result = Function::Create(
 300       TypeBuilder<int64_t(void), false>::get(Context),
 301       GlobalValue::ExternalLinkage, "__main", M.get());
 302   } else {
 303     Result = Function::Create(
 304       TypeBuilder<int32_t(void), false>::get(Context),
 305       GlobalValue::ExternalLinkage, "__main", M.get());
 306   }
 307   BasicBlock *BB = BasicBlock::Create(Context, "__main", Result);
 308   Builder.SetInsertPoint(BB);
 309   Value *ReturnVal;
 310   if (TargetTriple.isArch64Bit())
 311     ReturnVal = ConstantInt::get(Context, APInt(64, 0));
 312   else
 313     ReturnVal = ConstantInt::get(Context, APInt(32, 0));
 314   Builder.CreateRet(ReturnVal);
 315
 316   // Add this new module to the ExecutionEngine.
 317   EE.addModule(std::move(M));
 318 }
 319
 320 CodeGenOpt::Level getOptLevel() {
 321   switch (OptLevel) {
 322   default:
 323     WithColor::error(errs(), "lli") << "invalid optimization level.\n";
 324     exit(1);
 325   case '0': return CodeGenOpt::None;
 326   case '1': return CodeGenOpt::Less;
 327   case ' ':
 328   case '2': return CodeGenOpt::Default;
 329   case '3': return CodeGenOpt::Aggressive;
 330   }
 331   llvm_unreachable("Unrecognized opt level.");
 332 }
 333
 334 LLVM_ATTRIBUTE_NORETURN
 335 static void reportError(SMDiagnostic Err, const char *ProgName) {
 336   Err.print(ProgName, errs());
 337   exit(1);
 338 }
 339
 340 int runOrcLazyJIT(LLVMContext &Ctx, std::vector<std::unique_ptr<Module>> Ms,
 341                   const std::vector<std::string> &Args);
 342
 343 //===----------------------------------------------------------------------===//
 344 // main Driver function
 345 //
 346 int main(int argc, char **argv, char * const *envp) {
 347   InitLLVM X(argc, argv);
 348
 349   if (argc > 1)
 350     ExitOnErr.setBanner(std::string(argv[0]) + ": ");
 351
 352   // If we have a native target, initialize it to ensure it is linked in and
 353   // usable by the JIT.
 354   InitializeNativeTarget();
 355   InitializeNativeTargetAsmPrinter();
 356   InitializeNativeTargetAsmParser();
 357
 358   cl::ParseCommandLineOptions(argc, argv,
 359                               "llvm interpreter & dynamic compiler\n");
 360
 361   // If the user doesn't want core files, disable them.
 362   if (DisableCoreFiles)
 363     sys::Process::PreventCoreFiles();
 364
 365   LLVMContext Context;
 366
 367   // Load the bitcode...
 368   SMDiagnostic Err;
 369   std::unique_ptr<Module> Owner = parseIRFile(InputFile, Err, Context);
 370   Module *Mod = Owner.get();
 371   if (!Mod)
 372     reportError(Err, argv[0]);
 373
 374   if (UseJITKind == JITKind::OrcLazy) {
 375     std::vector<std::unique_ptr<Module>> Ms;
 376     Ms.push_back(std::move(Owner));
 377     for (auto &ExtraMod : ExtraModules) {
 378       Ms.push_back(parseIRFile(ExtraMod, Err, Context));
 379       if (!Ms.back())
 380         reportError(Err, argv[0]);
 381     }
 382     std::vector<std::string> Args;
 383     Args.push_back(InputFile);
 384     for (auto &Arg : InputArgv)
 385       Args.push_back(Arg);
 386     return runOrcLazyJIT(Context, std::move(Ms), Args);
 387   }
 388
 389   if (EnableCacheManager) {
 390     std::string CacheName("file:");
 391     CacheName.append(InputFile);
 392     Mod->setModuleIdentifier(CacheName);
 393   }
 394
 395   // If not jitting lazily, load the whole bitcode file eagerly too.
 396   if (NoLazyCompilation) {
 397     // Use *argv instead of argv[0] to work around a wrong GCC warning.
 398     ExitOnError ExitOnErr(std::string(*argv) +
 399                           ": bitcode didn't read correctly: ");
 400     ExitOnErr(Mod->materializeAll());
 401   }
 402
 403   std::string ErrorMsg;
 404   EngineBuilder builder(std::move(Owner));
 405   builder.setMArch(MArch);
 406   builder.setMCPU(getCPUStr());
 407   builder.setMAttrs(getFeatureList());
 408   if (RelocModel.getNumOccurrences())
 409     builder.setRelocationModel(RelocModel);
 410   if (CMModel.getNumOccurrences())
 411     builder.setCodeModel(CMModel);
 412   builder.setErrorStr(&ErrorMsg);
 413   builder.setEngineKind(ForceInterpreter
 414                         ? EngineKind::Interpreter
 415                         : EngineKind::JIT);
 416   builder.setUseOrcMCJITReplacement(UseJITKind == JITKind::OrcMCJITReplacement);
 417
 418   // If we are supposed to override the target triple, do so now.
 419   if (!TargetTriple.empty())
 420     Mod->setTargetTriple(Triple::normalize(TargetTriple));
 421
 422   // Enable MCJIT if desired.
 423   RTDyldMemoryManager *RTDyldMM = nullptr;
 424   if (!ForceInterpreter) {
 425     if (RemoteMCJIT)
 426       RTDyldMM = new ForwardingMemoryManager();
 427     else
 428       RTDyldMM = new SectionMemoryManager();
 429
 430     // Deliberately construct a temp std::unique_ptr to pass in. Do not null out
 431     // RTDyldMM: We still use it below, even though we don't own it.
 432     builder.setMCJITMemoryManager(
 433       std::unique_ptr<RTDyldMemoryManager>(RTDyldMM));
 434   } else if (RemoteMCJIT) {
 435     WithColor::error(errs(), argv[0])
 436         << "remote process execution does not work with the interpreter.\n";
 437     exit(1);
 438   }
 439
 440   builder.setOptLevel(getOptLevel());
 441
 442   TargetOptions Options = InitTargetOptionsFromCodeGenFlags();
 443   if (FloatABIForCalls != FloatABI::Default)
 444     Options.FloatABIType = FloatABIForCalls;
 445
 446   builder.setTargetOptions(Options);
 447
 448   std::unique_ptr<ExecutionEngine> EE(builder.create());
 449   if (!EE) {
 450     if (!ErrorMsg.empty())
 451       WithColor::error(errs(), argv[0])
 452           << "error creating EE: " << ErrorMsg << "\n";
 453     else
 454       WithColor::error(errs(), argv[0]) << "unknown error creating EE!\n";
 455     exit(1);
 456   }
 457
 458   std::unique_ptr<LLIObjectCache> CacheManager;
 459   if (EnableCacheManager) {
 460     CacheManager.reset(new LLIObjectCache(ObjectCacheDir));
 461     EE->setObjectCache(CacheManager.get());
 462   }
 463
 464   // Load any additional modules specified on the command line.
 465   for (unsigned i = 0, e = ExtraModules.size(); i != e; ++i) {
 466     std::unique_ptr<Module> XMod = parseIRFile(ExtraModules[i], Err, Context);
 467     if (!XMod)
 468       reportError(Err, argv[0]);
 469     if (EnableCacheManager) {
 470       std::string CacheName("file:");
 471       CacheName.append(ExtraModules[i]);
 472       XMod->setModuleIdentifier(CacheName);
 473     }
 474     EE->addModule(std::move(XMod));
 475   }
 476
 477   for (unsigned i = 0, e = ExtraObjects.size(); i != e; ++i) {
 478     Expected<object::OwningBinary<object::ObjectFile>> Obj =
 479         object::ObjectFile::createObjectFile(ExtraObjects[i]);
 480     if (!Obj) {
 481       // TODO: Actually report errors helpfully.
 482       consumeError(Obj.takeError());
 483       reportError(Err, argv[0]);
 484     }
 485     object::OwningBinary<object::ObjectFile> &O = Obj.get();
 486     EE->addObjectFile(std::move(O));
 487   }
 488
 489   for (unsigned i = 0, e = ExtraArchives.size(); i != e; ++i) {
 490     ErrorOr<std::unique_ptr<MemoryBuffer>> ArBufOrErr =
 491         MemoryBuffer::getFileOrSTDIN(ExtraArchives[i]);
 492     if (!ArBufOrErr)
 493       reportError(Err, argv[0]);
 494     std::unique_ptr<MemoryBuffer> &ArBuf = ArBufOrErr.get();
 495
 496     Expected<std::unique_ptr<object::Archive>> ArOrErr =
 497         object::Archive::create(ArBuf->getMemBufferRef());
 498     if (!ArOrErr) {
 499       std::string Buf;
 500       raw_string_ostream OS(Buf);
 501       logAllUnhandledErrors(ArOrErr.takeError(), OS, "");
 502       OS.flush();
 503       errs() << Buf;
 504       exit(1);
 505     }
 506     std::unique_ptr<object::Archive> &Ar = ArOrErr.get();
 507
 508     object::OwningBinary<object::Archive> OB(std::move(Ar), std::move(ArBuf));
 509
 510     EE->addArchive(std::move(OB));
 511   }
 512
 513   // If the target is Cygwin/MingW and we are generating remote code, we
 514   // need an extra module to help out with linking.
 515   if (RemoteMCJIT && Triple(Mod->getTargetTriple()).isOSCygMing()) {
 516     addCygMingExtraModule(*EE, Context, Mod->getTargetTriple());
 517   }
 518
 519   // The following functions have no effect if their respective profiling
 520   // support wasn't enabled in the build configuration.
 521   EE->RegisterJITEventListener(
 522                 JITEventListener::createOProfileJITEventListener());
 523   EE->RegisterJITEventListener(
 524                 JITEventListener::createIntelJITEventListener());
 525   if (!RemoteMCJIT)
 526     EE->RegisterJITEventListener(
 527                 JITEventListener::createPerfJITEventListener());
 528
 529   if (!NoLazyCompilation && RemoteMCJIT) {
 530     WithColor::warning(errs(), argv[0])
 531         << "remote mcjit does not support lazy compilation\n";
 532     NoLazyCompilation = true;
 533   }
 534   EE->DisableLazyCompilation(NoLazyCompilation);
 535
 536   // If the user specifically requested an argv[0] to pass into the program,
 537   // do it now.
 538   if (!FakeArgv0.empty()) {
 539     InputFile = static_cast<std::string>(FakeArgv0);
 540   } else {
 541     // Otherwise, if there is a .bc suffix on the executable strip it off, it
 542     // might confuse the program.
 543     if (StringRef(InputFile).endswith(".bc"))
 544       InputFile.erase(InputFile.length() - 3);
 545   }
 546
 547   // Add the module's name to the start of the vector of arguments to main().
 548   InputArgv.insert(InputArgv.begin(), InputFile);
 549
 550   // Call the main function from M as if its signature were:
 551   //   int main (int argc, char **argv, const char **envp)
 552   // using the contents of Args to determine argc & argv, and the contents of
 553   // EnvVars to determine envp.
 554   //
 555   Function *EntryFn = Mod->getFunction(EntryFunc);
 556   if (!EntryFn) {
 557     WithColor::error(errs(), argv[0])
 558         << '\'' << EntryFunc << "\' function not found in module.\n";
 559     return -1;
 560   }
 561
 562   // Reset errno to zero on entry to main.
 563   errno = 0;
 564
 565   int Result = -1;
 566
 567   // Sanity check use of remote-jit: LLI currently only supports use of the
 568   // remote JIT on Unix platforms.
 569   if (RemoteMCJIT) {
 570 #ifndef LLVM_ON_UNIX
 571     WithColor::warning(errs(), argv[0])
 572         << "host does not support external remote targets.\n";
 573     WithColor::note() << "defaulting to local execution\n";
 574     return -1;
 575 #else
 576     if (ChildExecPath.empty()) {
 577       WithColor::error(errs(), argv[0])
 578           << "-remote-mcjit requires -mcjit-remote-process.\n";
 579       exit(1);
 580     } else if (!sys::fs::can_execute(ChildExecPath)) {
 581       WithColor::error(errs(), argv[0])
 582           << "unable to find usable child executable: '" << ChildExecPath
 583           << "'\n";
 584       return -1;
 585     }
 586 #endif
 587   }
 588
 589   if (!RemoteMCJIT) {
 590     // If the program doesn't explicitly call exit, we will need the Exit
 591     // function later on to make an explicit call, so get the function now.
 592     Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context),
 593                                                       Type::getInt32Ty(Context));
 594
 595     // Run static constructors.
 596     if (!ForceInterpreter) {
 597       // Give MCJIT a chance to apply relocations and set page permissions.
 598       EE->finalizeObject();
 599     }
 600     EE->runStaticConstructorsDestructors(false);
 601
 602     // Trigger compilation separately so code regions that need to be
 603     // invalidated will be known.
 604     (void)EE->getPointerToFunction(EntryFn);
 605     // Clear instruction cache before code will be executed.
 606     if (RTDyldMM)
 607       static_cast<SectionMemoryManager*>(RTDyldMM)->invalidateInstructionCache();
 608
 609     // Run main.
 610     Result = EE->runFunctionAsMain(EntryFn, InputArgv, envp);
 611
 612     // Run static destructors.
 613     EE->runStaticConstructorsDestructors(true);
 614
 615     // If the program didn't call exit explicitly, we should call it now.
 616     // This ensures that any atexit handlers get called correctly.
 617     if (Function *ExitF = dyn_cast<Function>(Exit)) {
 618       std::vector<GenericValue> Args;
 619       GenericValue ResultGV;
 620       ResultGV.IntVal = APInt(32, Result);
 621       Args.push_back(ResultGV);
 622       EE->runFunction(ExitF, Args);
 623       WithColor::error(errs(), argv[0]) << "exit(" << Result << ") returned!\n";
 624       abort();
 625     } else {
 626       WithColor::error(errs(), argv[0])
 627           << "exit defined with wrong prototype!\n";
 628       abort();
 629     }
 630   } else {
 631     // else == "if (RemoteMCJIT)"
 632
 633     // Remote target MCJIT doesn't (yet) support static constructors. No reason
 634     // it couldn't. This is a limitation of the LLI implementation, not the
 635     // MCJIT itself. FIXME.
 636
 637     // Lanch the remote process and get a channel to it.
 638     std::unique_ptr<FDRawChannel> C = launchRemote();
 639     if (!C) {
 640       WithColor::error(errs(), argv[0]) << "failed to launch remote JIT.\n";
 641       exit(1);
 642     }
 643
 644     // Create a remote target client running over the channel.
 645     llvm::orc::ExecutionSession ES;
 646     ES.setErrorReporter([&](Error Err) { ExitOnErr(std::move(Err)); });
 647     typedef orc::remote::OrcRemoteTargetClient MyRemote;
 648     auto R = ExitOnErr(MyRemote::Create(*C, ES));
 649
 650     // Create a remote memory manager.
 651     auto RemoteMM = ExitOnErr(R->createRemoteMemoryManager());
 652
 653     // Forward MCJIT's memory manager calls to the remote memory manager.
 654     static_cast<ForwardingMemoryManager*>(RTDyldMM)->setMemMgr(
 655       std::move(RemoteMM));
 656
 657     // Forward MCJIT's symbol resolution calls to the remote.
 658     static_cast<ForwardingMemoryManager *>(RTDyldMM)->setResolver(
 659         orc::createLambdaResolver(
 660             [](const std::string &Name) { return nullptr; },
 661             [&](const std::string &Name) {
 662               if (auto Addr = ExitOnErr(R->getSymbolAddress(Name)))
 663                 return JITSymbol(Addr, JITSymbolFlags::Exported);
 664               return JITSymbol(nullptr);
 665             }));
 666
 667     // Grab the target address of the JIT'd main function on the remote and call
 668     // it.
 669     // FIXME: argv and envp handling.
 670     JITTargetAddress Entry = EE->getFunctionAddress(EntryFn->getName().str());
 671     EE->finalizeObject();
 672     LLVM_DEBUG(dbgs() << "Executing '" << EntryFn->getName() << "' at 0x"
 673                       << format("%llx", Entry) << "\n");
 674     Result = ExitOnErr(R->callIntVoid(Entry));
 675
 676     // Like static constructors, the remote target MCJIT support doesn't handle
 677     // this yet. It could. FIXME.
 678
 679     // Delete the EE - we need to tear it down *before* we terminate the session
 680     // with the remote, otherwise it'll crash when it tries to release resources
 681     // on a remote that has already been disconnected.
 682     EE.reset();
 683
 684     // Signal the remote target that we're done JITing.
 685     ExitOnErr(R->terminateSession());
 686   }
 687
 688   return Result;
 689 }
 690
 691 static orc::IRTransformLayer2::TransformFunction createDebugDumper() {
 692   switch (OrcDumpKind) {
 693   case DumpKind::NoDump:
 694     return [](std::unique_ptr<Module> M) { return M; };
 695
 696   case DumpKind::DumpFuncsToStdOut:
 697     return [](std::unique_ptr<Module> M) {
 698       printf("[ ");
 699
 700       for (const auto &F : *M) {
 701         if (F.isDeclaration())
 702           continue;
 703
 704         if (F.hasName()) {
 705           std::string Name(F.getName());
 706           printf("%s ", Name.c_str());
 707         } else
 708           printf("<anon> ");
 709       }
 710
 711       printf("]\n");
 712       return M;
 713     };
 714
 715   case DumpKind::DumpModsToStdOut:
 716     return [](std::unique_ptr<Module> M) {
 717       outs() << "----- Module Start -----\n"
 718              << *M << "----- Module End -----\n";
 719
 720       return M;
 721     };
 722
 723   case DumpKind::DumpModsToDisk:
 724     return [](std::unique_ptr<Module> M) {
 725       std::error_code EC;
 726       raw_fd_ostream Out(M->getModuleIdentifier() + ".ll", EC, sys::fs::F_Text);
 727       if (EC) {
 728         errs() << "Couldn't open " << M->getModuleIdentifier()
 729                << " for dumping.\nError:" << EC.message() << "\n";
 730         exit(1);
 731       }
 732       Out << *M;
 733       return M;
 734     };
 735   }
 736   llvm_unreachable("Unknown DumpKind");
 737 }
 738
 739 int runOrcLazyJIT(LLVMContext &Ctx, std::vector<std::unique_ptr<Module>> Ms,
 740                   const std::vector<std::string> &Args) {
 741   // Bail out early if no modules loaded.
 742   if (Ms.empty())
 743     return 0;
 744
 745   // Add lli's symbols into the JIT's search space.
 746   std::string ErrMsg;
 747   sys::DynamicLibrary LibLLI =
 748       sys::DynamicLibrary::getPermanentLibrary(nullptr, &ErrMsg);
 749   if (!LibLLI.isValid()) {
 750     errs() << "Error loading lli symbols: " << ErrMsg << ".\n";
 751     return 1;
 752   }
 753
 754   const auto &TT = Ms.front()->getTargetTriple();
 755   orc::JITTargetMachineBuilder TMD =
 756       TT.empty() ? ExitOnErr(orc::JITTargetMachineBuilder::detectHost())
 757                  : orc::JITTargetMachineBuilder(Triple(TT));
 758
 759   TMD.setArch(MArch)
 760       .setCPU(getCPUStr())
 761       .addFeatures(getFeatureList())
 762       .setRelocationModel(RelocModel.getNumOccurrences()
 763                               ? Optional<Reloc::Model>(RelocModel)
 764                               : None)
 765       .setCodeModel(CMModel.getNumOccurrences()
 766                         ? Optional<CodeModel::Model>(CMModel)
 767                         : None);
 768   auto TM = ExitOnErr(TMD.createTargetMachine());
 769   auto DL = TM->createDataLayout();
 770   auto ES = llvm::make_unique<orc::ExecutionSession>();
 771   auto J =
 772       ExitOnErr(orc::LLLazyJIT::Create(std::move(ES), std::move(TM), DL, Ctx));
 773
 774   auto Dump = createDebugDumper();
 775
 776   J->setLazyCompileTransform(
 777     [&](std::unique_ptr<Module> M) {
 778       if (verifyModule(*M, &dbgs())) {
 779         dbgs() << "Bad module: " << *M << "\n";
 780         exit(1);
 781       }
 782       return Dump(std::move(M));
 783     });
 784   J->getMainJITDylib().setFallbackDefinitionGenerator(
 785       orc::DynamicLibraryFallbackGenerator(
 786           std::move(LibLLI), DL, [](orc::SymbolStringPtr) { return true; }));
 787
 788   orc::MangleAndInterner Mangle(J->getExecutionSession(), DL);
 789   orc::LocalCXXRuntimeOverrides2 CXXRuntimeOverrides;
 790   ExitOnErr(CXXRuntimeOverrides.enable(J->getMainJITDylib(), Mangle));
 791
 792   for (auto &M : Ms) {
 793     orc::makeAllSymbolsExternallyAccessible(*M);
 794     ExitOnErr(J->addLazyIRModule(std::move(M)));
 795   }
 796
 797   ExitOnErr(J->runConstructors());
 798
 799   auto MainSym = ExitOnErr(J->lookup("main"));
 800   typedef int (*MainFnPtr)(int, const char *[]);
 801   std::vector<const char *> ArgV;
 802   for (auto &Arg : Args)
 803     ArgV.push_back(Arg.c_str());
 804   auto Main =
 805       reinterpret_cast<MainFnPtr>(static_cast<uintptr_t>(MainSym.getAddress()));
 806   auto Result = Main(ArgV.size(), (const char **)ArgV.data());
 807
 808   ExitOnErr(J->runDestructors());
 809
 810   CXXRuntimeOverrides.runDestructors();
 811
 812   return Result;
 813 }
 814
 815 std::unique_ptr<FDRawChannel> launchRemote() {
 816 #ifndef LLVM_ON_UNIX
 817   llvm_unreachable("launchRemote not supported on non-Unix platforms");
 818 #else
 819   int PipeFD[2][2];
 820   pid_t ChildPID;
 821
 822   // Create two pipes.
 823   if (pipe(PipeFD[0]) != 0 || pipe(PipeFD[1]) != 0)
 824     perror("Error creating pipe: ");
 825
 826   ChildPID = fork();
 827
 828   if (ChildPID == 0) {
 829     // In the child...
 830
 831     // Close the parent ends of the pipes
 832     close(PipeFD[0][1]);
 833     close(PipeFD[1][0]);
 834
 835
 836     // Execute the child process.
 837     std::unique_ptr<char[]> ChildPath, ChildIn, ChildOut;
 838     {
 839       ChildPath.reset(new char[ChildExecPath.size() + 1]);
 840       std::copy(ChildExecPath.begin(), ChildExecPath.end(), &ChildPath[0]);
 841       ChildPath[ChildExecPath.size()] = '\0';
 842       std::string ChildInStr = utostr(PipeFD[0][0]);
 843       ChildIn.reset(new char[ChildInStr.size() + 1]);
 844       std::copy(ChildInStr.begin(), ChildInStr.end(), &ChildIn[0]);
 845       ChildIn[ChildInStr.size()] = '\0';
 846       std::string ChildOutStr = utostr(PipeFD[1][1]);
 847       ChildOut.reset(new char[ChildOutStr.size() + 1]);
 848       std::copy(ChildOutStr.begin(), ChildOutStr.end(), &ChildOut[0]);
 849       ChildOut[ChildOutStr.size()] = '\0';
 850     }
 851
 852     char * const args[] = { &ChildPath[0], &ChildIn[0], &ChildOut[0], nullptr };
 853     int rc = execv(ChildExecPath.c_str(), args);
 854     if (rc != 0)
 855       perror("Error executing child process: ");
 856     llvm_unreachable("Error executing child process");
 857   }
 858   // else we're the parent...
 859
 860   // Close the child ends of the pipes
 861   close(PipeFD[0][0]);
 862   close(PipeFD[1][1]);
 863
 864   // Return an RPC channel connected to our end of the pipes.
 865   return llvm::make_unique<FDRawChannel>(PipeFD[1][0], PipeFD[0][1]);
 866 #endif
 867 }