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 #define DEBUG_TYPE "lli" 17 #include "llvm/IR/LLVMContext.h" 18 #include "RecordingMemoryManager.h" 19 #include "RemoteTarget.h" 20 #include "llvm/ADT/Triple.h" 21 #include "llvm/Bitcode/ReaderWriter.h" 22 #include "llvm/CodeGen/LinkAllCodegenComponents.h" 23 #include "llvm/ExecutionEngine/GenericValue.h" 24 #include "llvm/ExecutionEngine/Interpreter.h" 25 #include "llvm/ExecutionEngine/JIT.h" 26 #include "llvm/ExecutionEngine/JITEventListener.h" 27 #include "llvm/ExecutionEngine/JITMemoryManager.h" 28 #include "llvm/ExecutionEngine/MCJIT.h" 29 #include "llvm/ExecutionEngine/SectionMemoryManager.h" 30 #include "llvm/IR/Module.h" 31 #include "llvm/IR/Type.h" 32 #include "llvm/Support/CommandLine.h" 33 #include "llvm/Support/Debug.h" 34 #include "llvm/Support/DynamicLibrary.h" 35 #include "llvm/Support/Format.h" 36 #include "llvm/Support/IRReader.h" 37 #include "llvm/Support/ManagedStatic.h" 38 #include "llvm/Support/MathExtras.h" 39 #include "llvm/Support/Memory.h" 40 #include "llvm/Support/MemoryBuffer.h" 41 #include "llvm/Support/PluginLoader.h" 42 #include "llvm/Support/PrettyStackTrace.h" 43 #include "llvm/Support/Process.h" 44 #include "llvm/Support/Signals.h" 45 #include "llvm/Support/TargetSelect.h" 46 #include "llvm/Support/raw_ostream.h" 47 #include <cerrno> 48 49 #ifdef __CYGWIN__ 50 #include <cygwin/version.h> 51 #if defined(CYGWIN_VERSION_DLL_MAJOR) && CYGWIN_VERSION_DLL_MAJOR<1007 52 #define DO_NOTHING_ATEXIT 1 53 #endif 54 #endif 55 56 using namespace llvm; 57 58 namespace { 59 cl::opt<std::string> 60 InputFile(cl::desc("<input bitcode>"), cl::Positional, cl::init("-")); 61 62 cl::list<std::string> 63 InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>...")); 64 65 cl::opt<bool> ForceInterpreter("force-interpreter", 66 cl::desc("Force interpretation: disable JIT"), 67 cl::init(false)); 68 69 cl::opt<bool> UseMCJIT( 70 "use-mcjit", cl::desc("Enable use of the MC-based JIT (if available)"), 71 cl::init(false)); 72 73 // The MCJIT supports building for a target address space separate from 74 // the JIT compilation process. Use a forked process and a copying 75 // memory manager with IPC to execute using this functionality. 76 cl::opt<bool> RemoteMCJIT("remote-mcjit", 77 cl::desc("Execute MCJIT'ed code in a separate process."), 78 cl::init(false)); 79 80 // Determine optimization level. 81 cl::opt<char> 82 OptLevel("O", 83 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] " 84 "(default = '-O2')"), 85 cl::Prefix, 86 cl::ZeroOrMore, 87 cl::init(' ')); 88 89 cl::opt<std::string> 90 TargetTriple("mtriple", cl::desc("Override target triple for module")); 91 92 cl::opt<std::string> 93 MArch("march", 94 cl::desc("Architecture to generate assembly for (see --version)")); 95 96 cl::opt<std::string> 97 MCPU("mcpu", 98 cl::desc("Target a specific cpu type (-mcpu=help for details)"), 99 cl::value_desc("cpu-name"), 100 cl::init("")); 101 102 cl::list<std::string> 103 MAttrs("mattr", 104 cl::CommaSeparated, 105 cl::desc("Target specific attributes (-mattr=help for details)"), 106 cl::value_desc("a1,+a2,-a3,...")); 107 108 cl::opt<std::string> 109 EntryFunc("entry-function", 110 cl::desc("Specify the entry function (default = 'main') " 111 "of the executable"), 112 cl::value_desc("function"), 113 cl::init("main")); 114 115 cl::opt<std::string> 116 FakeArgv0("fake-argv0", 117 cl::desc("Override the 'argv[0]' value passed into the executing" 118 " program"), cl::value_desc("executable")); 119 120 cl::opt<bool> 121 DisableCoreFiles("disable-core-files", cl::Hidden, 122 cl::desc("Disable emission of core files if possible")); 123 124 cl::opt<bool> 125 NoLazyCompilation("disable-lazy-compilation", 126 cl::desc("Disable JIT lazy compilation"), 127 cl::init(false)); 128 129 cl::opt<Reloc::Model> 130 RelocModel("relocation-model", 131 cl::desc("Choose relocation model"), 132 cl::init(Reloc::Default), 133 cl::values( 134 clEnumValN(Reloc::Default, "default", 135 "Target default relocation model"), 136 clEnumValN(Reloc::Static, "static", 137 "Non-relocatable code"), 138 clEnumValN(Reloc::PIC_, "pic", 139 "Fully relocatable, position independent code"), 140 clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic", 141 "Relocatable external references, non-relocatable code"), 142 clEnumValEnd)); 143 144 cl::opt<llvm::CodeModel::Model> 145 CMModel("code-model", 146 cl::desc("Choose code model"), 147 cl::init(CodeModel::JITDefault), 148 cl::values(clEnumValN(CodeModel::JITDefault, "default", 149 "Target default JIT code model"), 150 clEnumValN(CodeModel::Small, "small", 151 "Small code model"), 152 clEnumValN(CodeModel::Kernel, "kernel", 153 "Kernel code model"), 154 clEnumValN(CodeModel::Medium, "medium", 155 "Medium code model"), 156 clEnumValN(CodeModel::Large, "large", 157 "Large code model"), 158 clEnumValEnd)); 159 160 cl::opt<bool> 161 EnableJITExceptionHandling("jit-enable-eh", 162 cl::desc("Emit exception handling information"), 163 cl::init(false)); 164 165 cl::opt<bool> 166 GenerateSoftFloatCalls("soft-float", 167 cl::desc("Generate software floating point library calls"), 168 cl::init(false)); 169 170 cl::opt<llvm::FloatABI::ABIType> 171 FloatABIForCalls("float-abi", 172 cl::desc("Choose float ABI type"), 173 cl::init(FloatABI::Default), 174 cl::values( 175 clEnumValN(FloatABI::Default, "default", 176 "Target default float ABI type"), 177 clEnumValN(FloatABI::Soft, "soft", 178 "Soft float ABI (implied by -soft-float)"), 179 clEnumValN(FloatABI::Hard, "hard", 180 "Hard float ABI (uses FP registers)"), 181 clEnumValEnd)); 182 cl::opt<bool> 183 // In debug builds, make this default to true. 184 #ifdef NDEBUG 185 #define EMIT_DEBUG false 186 #else 187 #define EMIT_DEBUG true 188 #endif 189 EmitJitDebugInfo("jit-emit-debug", 190 cl::desc("Emit debug information to debugger"), 191 cl::init(EMIT_DEBUG)); 192 #undef EMIT_DEBUG 193 194 static cl::opt<bool> 195 EmitJitDebugInfoToDisk("jit-emit-debug-to-disk", 196 cl::Hidden, 197 cl::desc("Emit debug info objfiles to disk"), 198 cl::init(false)); 199 } 200 201 static ExecutionEngine *EE = 0; 202 203 static void do_shutdown() { 204 // Cygwin-1.5 invokes DLL's dtors before atexit handler. 205 #ifndef DO_NOTHING_ATEXIT 206 delete EE; 207 llvm_shutdown(); 208 #endif 209 } 210 211 void layoutRemoteTargetMemory(RemoteTarget *T, RecordingMemoryManager *JMM) { 212 // Lay out our sections in order, with all the code sections first, then 213 // all the data sections. 214 uint64_t CurOffset = 0; 215 unsigned MaxAlign = T->getPageAlignment(); 216 SmallVector<std::pair<const void*, uint64_t>, 16> Offsets; 217 SmallVector<unsigned, 16> Sizes; 218 for (RecordingMemoryManager::const_code_iterator I = JMM->code_begin(), 219 E = JMM->code_end(); 220 I != E; ++I) { 221 DEBUG(dbgs() << "code region: size " << I->first.size() 222 << ", alignment " << I->second << "\n"); 223 // Align the current offset up to whatever is needed for the next 224 // section. 225 unsigned Align = I->second; 226 CurOffset = (CurOffset + Align - 1) / Align * Align; 227 // Save off the address of the new section and allocate its space. 228 Offsets.push_back(std::pair<const void*,uint64_t>(I->first.base(), CurOffset)); 229 Sizes.push_back(I->first.size()); 230 CurOffset += I->first.size(); 231 } 232 // Adjust to keep code and data aligned on seperate pages. 233 CurOffset = (CurOffset + MaxAlign - 1) / MaxAlign * MaxAlign; 234 unsigned FirstDataIndex = Offsets.size(); 235 for (RecordingMemoryManager::const_data_iterator I = JMM->data_begin(), 236 E = JMM->data_end(); 237 I != E; ++I) { 238 DEBUG(dbgs() << "data region: size " << I->first.size() 239 << ", alignment " << I->second << "\n"); 240 // Align the current offset up to whatever is needed for the next 241 // section. 242 unsigned Align = I->second; 243 CurOffset = (CurOffset + Align - 1) / Align * Align; 244 // Save off the address of the new section and allocate its space. 245 Offsets.push_back(std::pair<const void*,uint64_t>(I->first.base(), CurOffset)); 246 Sizes.push_back(I->first.size()); 247 CurOffset += I->first.size(); 248 } 249 250 // Allocate space in the remote target. 251 uint64_t RemoteAddr; 252 if (T->allocateSpace(CurOffset, MaxAlign, RemoteAddr)) 253 report_fatal_error(T->getErrorMsg()); 254 // Map the section addresses so relocations will get updated in the local 255 // copies of the sections. 256 for (unsigned i = 0, e = Offsets.size(); i != e; ++i) { 257 uint64_t Addr = RemoteAddr + Offsets[i].second; 258 EE->mapSectionAddress(const_cast<void*>(Offsets[i].first), Addr); 259 260 DEBUG(dbgs() << " Mapping local: " << Offsets[i].first 261 << " to remote: " << format("%p", Addr) << "\n"); 262 263 } 264 265 // Trigger application of relocations 266 EE->finalizeObject(); 267 268 // Now load it all to the target. 269 for (unsigned i = 0, e = Offsets.size(); i != e; ++i) { 270 uint64_t Addr = RemoteAddr + Offsets[i].second; 271 272 if (i < FirstDataIndex) { 273 T->loadCode(Addr, Offsets[i].first, Sizes[i]); 274 275 DEBUG(dbgs() << " loading code: " << Offsets[i].first 276 << " to remote: " << format("%p", Addr) << "\n"); 277 } else { 278 T->loadData(Addr, Offsets[i].first, Sizes[i]); 279 280 DEBUG(dbgs() << " loading data: " << Offsets[i].first 281 << " to remote: " << format("%p", Addr) << "\n"); 282 } 283 284 } 285 } 286 287 //===----------------------------------------------------------------------===// 288 // main Driver function 289 // 290 int main(int argc, char **argv, char * const *envp) { 291 sys::PrintStackTraceOnErrorSignal(); 292 PrettyStackTraceProgram X(argc, argv); 293 294 LLVMContext &Context = getGlobalContext(); 295 atexit(do_shutdown); // Call llvm_shutdown() on exit. 296 297 // If we have a native target, initialize it to ensure it is linked in and 298 // usable by the JIT. 299 InitializeNativeTarget(); 300 InitializeNativeTargetAsmPrinter(); 301 InitializeNativeTargetAsmParser(); 302 303 cl::ParseCommandLineOptions(argc, argv, 304 "llvm interpreter & dynamic compiler\n"); 305 306 // If the user doesn't want core files, disable them. 307 if (DisableCoreFiles) 308 sys::Process::PreventCoreFiles(); 309 310 // Load the bitcode... 311 SMDiagnostic Err; 312 Module *Mod = ParseIRFile(InputFile, Err, Context); 313 if (!Mod) { 314 Err.print(argv[0], errs()); 315 return 1; 316 } 317 318 // If not jitting lazily, load the whole bitcode file eagerly too. 319 std::string ErrorMsg; 320 if (NoLazyCompilation) { 321 if (Mod->MaterializeAllPermanently(&ErrorMsg)) { 322 errs() << argv[0] << ": bitcode didn't read correctly.\n"; 323 errs() << "Reason: " << ErrorMsg << "\n"; 324 exit(1); 325 } 326 } 327 328 EngineBuilder builder(Mod); 329 builder.setMArch(MArch); 330 builder.setMCPU(MCPU); 331 builder.setMAttrs(MAttrs); 332 builder.setRelocationModel(RelocModel); 333 builder.setCodeModel(CMModel); 334 builder.setErrorStr(&ErrorMsg); 335 builder.setEngineKind(ForceInterpreter 336 ? EngineKind::Interpreter 337 : EngineKind::JIT); 338 339 // If we are supposed to override the target triple, do so now. 340 if (!TargetTriple.empty()) 341 Mod->setTargetTriple(Triple::normalize(TargetTriple)); 342 343 // Enable MCJIT if desired. 344 JITMemoryManager *JMM = 0; 345 if (UseMCJIT && !ForceInterpreter) { 346 builder.setUseMCJIT(true); 347 if (RemoteMCJIT) 348 JMM = new RecordingMemoryManager(); 349 else 350 JMM = new SectionMemoryManager(); 351 builder.setJITMemoryManager(JMM); 352 } else { 353 if (RemoteMCJIT) { 354 errs() << "error: Remote process execution requires -use-mcjit\n"; 355 exit(1); 356 } 357 builder.setJITMemoryManager(ForceInterpreter ? 0 : 358 JITMemoryManager::CreateDefaultMemManager()); 359 } 360 361 CodeGenOpt::Level OLvl = CodeGenOpt::Default; 362 switch (OptLevel) { 363 default: 364 errs() << argv[0] << ": invalid optimization level.\n"; 365 return 1; 366 case ' ': break; 367 case '0': OLvl = CodeGenOpt::None; break; 368 case '1': OLvl = CodeGenOpt::Less; break; 369 case '2': OLvl = CodeGenOpt::Default; break; 370 case '3': OLvl = CodeGenOpt::Aggressive; break; 371 } 372 builder.setOptLevel(OLvl); 373 374 TargetOptions Options; 375 Options.UseSoftFloat = GenerateSoftFloatCalls; 376 if (FloatABIForCalls != FloatABI::Default) 377 Options.FloatABIType = FloatABIForCalls; 378 if (GenerateSoftFloatCalls) 379 FloatABIForCalls = FloatABI::Soft; 380 381 // Remote target execution doesn't handle EH or debug registration. 382 if (!RemoteMCJIT) { 383 Options.JITExceptionHandling = EnableJITExceptionHandling; 384 Options.JITEmitDebugInfo = EmitJitDebugInfo; 385 Options.JITEmitDebugInfoToDisk = EmitJitDebugInfoToDisk; 386 } 387 388 builder.setTargetOptions(Options); 389 390 EE = builder.create(); 391 if (!EE) { 392 if (!ErrorMsg.empty()) 393 errs() << argv[0] << ": error creating EE: " << ErrorMsg << "\n"; 394 else 395 errs() << argv[0] << ": unknown error creating EE!\n"; 396 exit(1); 397 } 398 399 // The following functions have no effect if their respective profiling 400 // support wasn't enabled in the build configuration. 401 EE->RegisterJITEventListener( 402 JITEventListener::createOProfileJITEventListener()); 403 EE->RegisterJITEventListener( 404 JITEventListener::createIntelJITEventListener()); 405 406 if (!NoLazyCompilation && RemoteMCJIT) { 407 errs() << "warning: remote mcjit does not support lazy compilation\n"; 408 NoLazyCompilation = true; 409 } 410 EE->DisableLazyCompilation(NoLazyCompilation); 411 412 // If the user specifically requested an argv[0] to pass into the program, 413 // do it now. 414 if (!FakeArgv0.empty()) { 415 InputFile = FakeArgv0; 416 } else { 417 // Otherwise, if there is a .bc suffix on the executable strip it off, it 418 // might confuse the program. 419 if (StringRef(InputFile).endswith(".bc")) 420 InputFile.erase(InputFile.length() - 3); 421 } 422 423 // Add the module's name to the start of the vector of arguments to main(). 424 InputArgv.insert(InputArgv.begin(), InputFile); 425 426 // Call the main function from M as if its signature were: 427 // int main (int argc, char **argv, const char **envp) 428 // using the contents of Args to determine argc & argv, and the contents of 429 // EnvVars to determine envp. 430 // 431 Function *EntryFn = Mod->getFunction(EntryFunc); 432 if (!EntryFn) { 433 errs() << '\'' << EntryFunc << "\' function not found in module.\n"; 434 return -1; 435 } 436 437 // If the program doesn't explicitly call exit, we will need the Exit 438 // function later on to make an explicit call, so get the function now. 439 Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context), 440 Type::getInt32Ty(Context), 441 NULL); 442 443 // Reset errno to zero on entry to main. 444 errno = 0; 445 446 // Remote target MCJIT doesn't (yet) support static constructors. No reason 447 // it couldn't. This is a limitation of the LLI implemantation, not the 448 // MCJIT itself. FIXME. 449 // 450 // Run static constructors. 451 if (!RemoteMCJIT) { 452 if (UseMCJIT && !ForceInterpreter) { 453 // Give MCJIT a chance to apply relocations and set page permissions. 454 EE->finalizeObject(); 455 } 456 EE->runStaticConstructorsDestructors(false); 457 } 458 459 if (NoLazyCompilation) { 460 for (Module::iterator I = Mod->begin(), E = Mod->end(); I != E; ++I) { 461 Function *Fn = &*I; 462 if (Fn != EntryFn && !Fn->isDeclaration()) 463 EE->getPointerToFunction(Fn); 464 } 465 } 466 467 int Result; 468 if (RemoteMCJIT) { 469 RecordingMemoryManager *MM = static_cast<RecordingMemoryManager*>(JMM); 470 // Everything is prepared now, so lay out our program for the target 471 // address space, assign the section addresses to resolve any relocations, 472 // and send it to the target. 473 RemoteTarget Target; 474 Target.create(); 475 476 // Ask for a pointer to the entry function. This triggers the actual 477 // compilation. 478 (void)EE->getPointerToFunction(EntryFn); 479 480 // Enough has been compiled to execute the entry function now, so 481 // layout the target memory. 482 layoutRemoteTargetMemory(&Target, MM); 483 484 // Since we're executing in a (at least simulated) remote address space, 485 // we can't use the ExecutionEngine::runFunctionAsMain(). We have to 486 // grab the function address directly here and tell the remote target 487 // to execute the function. 488 // FIXME: argv and envp handling. 489 uint64_t Entry = (uint64_t)EE->getPointerToFunction(EntryFn); 490 491 DEBUG(dbgs() << "Executing '" << EntryFn->getName() << "' at " 492 << format("%p", Entry) << "\n"); 493 494 if (Target.executeCode(Entry, Result)) 495 errs() << "ERROR: " << Target.getErrorMsg() << "\n"; 496 497 Target.stop(); 498 } else { 499 // Trigger compilation separately so code regions that need to be 500 // invalidated will be known. 501 (void)EE->getPointerToFunction(EntryFn); 502 // Clear instruction cache before code will be executed. 503 if (JMM) 504 static_cast<SectionMemoryManager*>(JMM)->invalidateInstructionCache(); 505 506 // Run main. 507 Result = EE->runFunctionAsMain(EntryFn, InputArgv, envp); 508 } 509 510 // Like static constructors, the remote target MCJIT support doesn't handle 511 // this yet. It could. FIXME. 512 if (!RemoteMCJIT) { 513 // Run static destructors. 514 EE->runStaticConstructorsDestructors(true); 515 516 // If the program didn't call exit explicitly, we should call it now. 517 // This ensures that any atexit handlers get called correctly. 518 if (Function *ExitF = dyn_cast<Function>(Exit)) { 519 std::vector<GenericValue> Args; 520 GenericValue ResultGV; 521 ResultGV.IntVal = APInt(32, Result); 522 Args.push_back(ResultGV); 523 EE->runFunction(ExitF, Args); 524 errs() << "ERROR: exit(" << Result << ") returned!\n"; 525 abort(); 526 } else { 527 errs() << "ERROR: exit defined with wrong prototype!\n"; 528 abort(); 529 } 530 } 531 return Result; 532 } 533