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