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 "llvm/LLVMContext.h" 17 #include "llvm/Module.h" 18 #include "llvm/Type.h" 19 #include "llvm/ADT/Triple.h" 20 #include "llvm/Bitcode/ReaderWriter.h" 21 #include "llvm/CodeGen/LinkAllCodegenComponents.h" 22 #include "llvm/ExecutionEngine/GenericValue.h" 23 #include "llvm/ExecutionEngine/Interpreter.h" 24 #include "llvm/ExecutionEngine/JIT.h" 25 #include "llvm/ExecutionEngine/JITEventListener.h" 26 #include "llvm/ExecutionEngine/MCJIT.h" 27 #include "llvm/Support/CommandLine.h" 28 #include "llvm/Support/IRReader.h" 29 #include "llvm/Support/ManagedStatic.h" 30 #include "llvm/Support/MemoryBuffer.h" 31 #include "llvm/Support/PluginLoader.h" 32 #include "llvm/Support/PrettyStackTrace.h" 33 #include "llvm/Support/raw_ostream.h" 34 #include "llvm/Support/Process.h" 35 #include "llvm/Support/Signals.h" 36 #include "llvm/Support/TargetSelect.h" 37 #include <cerrno> 38 39 #ifdef __CYGWIN__ 40 #include <cygwin/version.h> 41 #if defined(CYGWIN_VERSION_DLL_MAJOR) && CYGWIN_VERSION_DLL_MAJOR<1007 42 #define DO_NOTHING_ATEXIT 1 43 #endif 44 #endif 45 46 using namespace llvm; 47 48 namespace { 49 cl::opt<std::string> 50 InputFile(cl::desc("<input bitcode>"), cl::Positional, cl::init("-")); 51 52 cl::list<std::string> 53 InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>...")); 54 55 cl::opt<bool> ForceInterpreter("force-interpreter", 56 cl::desc("Force interpretation: disable JIT"), 57 cl::init(false)); 58 59 cl::opt<bool> UseMCJIT( 60 "use-mcjit", cl::desc("Enable use of the MC-based JIT (if available)"), 61 cl::init(false)); 62 63 // Determine optimization level. 64 cl::opt<char> 65 OptLevel("O", 66 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] " 67 "(default = '-O2')"), 68 cl::Prefix, 69 cl::ZeroOrMore, 70 cl::init(' ')); 71 72 cl::opt<std::string> 73 TargetTriple("mtriple", cl::desc("Override target triple for module")); 74 75 cl::opt<std::string> 76 MArch("march", 77 cl::desc("Architecture to generate assembly for (see --version)")); 78 79 cl::opt<std::string> 80 MCPU("mcpu", 81 cl::desc("Target a specific cpu type (-mcpu=help for details)"), 82 cl::value_desc("cpu-name"), 83 cl::init("")); 84 85 cl::list<std::string> 86 MAttrs("mattr", 87 cl::CommaSeparated, 88 cl::desc("Target specific attributes (-mattr=help for details)"), 89 cl::value_desc("a1,+a2,-a3,...")); 90 91 cl::opt<std::string> 92 EntryFunc("entry-function", 93 cl::desc("Specify the entry function (default = 'main') " 94 "of the executable"), 95 cl::value_desc("function"), 96 cl::init("main")); 97 98 cl::opt<std::string> 99 FakeArgv0("fake-argv0", 100 cl::desc("Override the 'argv[0]' value passed into the executing" 101 " program"), cl::value_desc("executable")); 102 103 cl::opt<bool> 104 DisableCoreFiles("disable-core-files", cl::Hidden, 105 cl::desc("Disable emission of core files if possible")); 106 107 cl::opt<bool> 108 NoLazyCompilation("disable-lazy-compilation", 109 cl::desc("Disable JIT lazy compilation"), 110 cl::init(false)); 111 112 cl::opt<Reloc::Model> 113 RelocModel("relocation-model", 114 cl::desc("Choose relocation model"), 115 cl::init(Reloc::Default), 116 cl::values( 117 clEnumValN(Reloc::Default, "default", 118 "Target default relocation model"), 119 clEnumValN(Reloc::Static, "static", 120 "Non-relocatable code"), 121 clEnumValN(Reloc::PIC_, "pic", 122 "Fully relocatable, position independent code"), 123 clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic", 124 "Relocatable external references, non-relocatable code"), 125 clEnumValEnd)); 126 127 cl::opt<llvm::CodeModel::Model> 128 CMModel("code-model", 129 cl::desc("Choose code model"), 130 cl::init(CodeModel::JITDefault), 131 cl::values(clEnumValN(CodeModel::JITDefault, "default", 132 "Target default JIT code model"), 133 clEnumValN(CodeModel::Small, "small", 134 "Small code model"), 135 clEnumValN(CodeModel::Kernel, "kernel", 136 "Kernel code model"), 137 clEnumValN(CodeModel::Medium, "medium", 138 "Medium code model"), 139 clEnumValN(CodeModel::Large, "large", 140 "Large code model"), 141 clEnumValEnd)); 142 143 } 144 145 static ExecutionEngine *EE = 0; 146 147 static void do_shutdown() { 148 // Cygwin-1.5 invokes DLL's dtors before atexit handler. 149 #ifndef DO_NOTHING_ATEXIT 150 delete EE; 151 llvm_shutdown(); 152 #endif 153 } 154 155 //===----------------------------------------------------------------------===// 156 // main Driver function 157 // 158 int main(int argc, char **argv, char * const *envp) { 159 sys::PrintStackTraceOnErrorSignal(); 160 PrettyStackTraceProgram X(argc, argv); 161 162 LLVMContext &Context = getGlobalContext(); 163 atexit(do_shutdown); // Call llvm_shutdown() on exit. 164 165 // If we have a native target, initialize it to ensure it is linked in and 166 // usable by the JIT. 167 InitializeNativeTarget(); 168 InitializeNativeTargetAsmPrinter(); 169 170 cl::ParseCommandLineOptions(argc, argv, 171 "llvm interpreter & dynamic compiler\n"); 172 173 // If the user doesn't want core files, disable them. 174 if (DisableCoreFiles) 175 sys::Process::PreventCoreFiles(); 176 177 // Load the bitcode... 178 SMDiagnostic Err; 179 Module *Mod = ParseIRFile(InputFile, Err, Context); 180 if (!Mod) { 181 Err.print(argv[0], errs()); 182 return 1; 183 } 184 185 // If not jitting lazily, load the whole bitcode file eagerly too. 186 std::string ErrorMsg; 187 if (NoLazyCompilation) { 188 if (Mod->MaterializeAllPermanently(&ErrorMsg)) { 189 errs() << argv[0] << ": bitcode didn't read correctly.\n"; 190 errs() << "Reason: " << ErrorMsg << "\n"; 191 exit(1); 192 } 193 } 194 195 EngineBuilder builder(Mod); 196 builder.setMArch(MArch); 197 builder.setMCPU(MCPU); 198 builder.setMAttrs(MAttrs); 199 builder.setRelocationModel(RelocModel); 200 builder.setCodeModel(CMModel); 201 builder.setErrorStr(&ErrorMsg); 202 builder.setEngineKind(ForceInterpreter 203 ? EngineKind::Interpreter 204 : EngineKind::JIT); 205 206 // If we are supposed to override the target triple, do so now. 207 if (!TargetTriple.empty()) 208 Mod->setTargetTriple(Triple::normalize(TargetTriple)); 209 210 // Enable MCJIT, if desired. 211 if (UseMCJIT) 212 builder.setUseMCJIT(true); 213 214 CodeGenOpt::Level OLvl = CodeGenOpt::Default; 215 switch (OptLevel) { 216 default: 217 errs() << argv[0] << ": invalid optimization level.\n"; 218 return 1; 219 case ' ': break; 220 case '0': OLvl = CodeGenOpt::None; break; 221 case '1': OLvl = CodeGenOpt::Less; break; 222 case '2': OLvl = CodeGenOpt::Default; break; 223 case '3': OLvl = CodeGenOpt::Aggressive; break; 224 } 225 builder.setOptLevel(OLvl); 226 227 EE = builder.create(); 228 if (!EE) { 229 if (!ErrorMsg.empty()) 230 errs() << argv[0] << ": error creating EE: " << ErrorMsg << "\n"; 231 else 232 errs() << argv[0] << ": unknown error creating EE!\n"; 233 exit(1); 234 } 235 236 EE->RegisterJITEventListener(createOProfileJITEventListener()); 237 238 EE->DisableLazyCompilation(NoLazyCompilation); 239 240 // If the user specifically requested an argv[0] to pass into the program, 241 // do it now. 242 if (!FakeArgv0.empty()) { 243 InputFile = FakeArgv0; 244 } else { 245 // Otherwise, if there is a .bc suffix on the executable strip it off, it 246 // might confuse the program. 247 if (StringRef(InputFile).endswith(".bc")) 248 InputFile.erase(InputFile.length() - 3); 249 } 250 251 // Add the module's name to the start of the vector of arguments to main(). 252 InputArgv.insert(InputArgv.begin(), InputFile); 253 254 // Call the main function from M as if its signature were: 255 // int main (int argc, char **argv, const char **envp) 256 // using the contents of Args to determine argc & argv, and the contents of 257 // EnvVars to determine envp. 258 // 259 Function *EntryFn = Mod->getFunction(EntryFunc); 260 if (!EntryFn) { 261 errs() << '\'' << EntryFunc << "\' function not found in module.\n"; 262 return -1; 263 } 264 265 // If the program doesn't explicitly call exit, we will need the Exit 266 // function later on to make an explicit call, so get the function now. 267 Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context), 268 Type::getInt32Ty(Context), 269 NULL); 270 271 // Reset errno to zero on entry to main. 272 errno = 0; 273 274 // Run static constructors. 275 EE->runStaticConstructorsDestructors(false); 276 277 if (NoLazyCompilation) { 278 for (Module::iterator I = Mod->begin(), E = Mod->end(); I != E; ++I) { 279 Function *Fn = &*I; 280 if (Fn != EntryFn && !Fn->isDeclaration()) 281 EE->getPointerToFunction(Fn); 282 } 283 } 284 285 // Run main. 286 int Result = EE->runFunctionAsMain(EntryFn, InputArgv, envp); 287 288 // Run static destructors. 289 EE->runStaticConstructorsDestructors(true); 290 291 // If the program didn't call exit explicitly, we should call it now. 292 // This ensures that any atexit handlers get called correctly. 293 if (Function *ExitF = dyn_cast<Function>(Exit)) { 294 std::vector<GenericValue> Args; 295 GenericValue ResultGV; 296 ResultGV.IntVal = APInt(32, Result); 297 Args.push_back(ResultGV); 298 EE->runFunction(ExitF, Args); 299 errs() << "ERROR: exit(" << Result << ") returned!\n"; 300 abort(); 301 } else { 302 errs() << "ERROR: exit defined with wrong prototype!\n"; 303 abort(); 304 } 305 } 306