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/Target/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 } 112 113 static ExecutionEngine *EE = 0; 114 115 static void do_shutdown() { 116 // Cygwin-1.5 invokes DLL's dtors before atexit handler. 117 #ifndef DO_NOTHING_ATEXIT 118 delete EE; 119 llvm_shutdown(); 120 #endif 121 } 122 123 //===----------------------------------------------------------------------===// 124 // main Driver function 125 // 126 int main(int argc, char **argv, char * const *envp) { 127 sys::PrintStackTraceOnErrorSignal(); 128 PrettyStackTraceProgram X(argc, argv); 129 130 LLVMContext &Context = getGlobalContext(); 131 atexit(do_shutdown); // Call llvm_shutdown() on exit. 132 133 // If we have a native target, initialize it to ensure it is linked in and 134 // usable by the JIT. 135 InitializeNativeTarget(); 136 InitializeNativeTargetAsmPrinter(); 137 138 cl::ParseCommandLineOptions(argc, argv, 139 "llvm interpreter & dynamic compiler\n"); 140 141 // If the user doesn't want core files, disable them. 142 if (DisableCoreFiles) 143 sys::Process::PreventCoreFiles(); 144 145 // Load the bitcode... 146 SMDiagnostic Err; 147 Module *Mod = ParseIRFile(InputFile, Err, Context); 148 if (!Mod) { 149 Err.Print(argv[0], errs()); 150 return 1; 151 } 152 153 // If not jitting lazily, load the whole bitcode file eagerly too. 154 std::string ErrorMsg; 155 if (NoLazyCompilation) { 156 if (Mod->MaterializeAllPermanently(&ErrorMsg)) { 157 errs() << argv[0] << ": bitcode didn't read correctly.\n"; 158 errs() << "Reason: " << ErrorMsg << "\n"; 159 exit(1); 160 } 161 } 162 163 EngineBuilder builder(Mod); 164 builder.setMArch(MArch); 165 builder.setMCPU(MCPU); 166 builder.setMAttrs(MAttrs); 167 builder.setErrorStr(&ErrorMsg); 168 builder.setEngineKind(ForceInterpreter 169 ? EngineKind::Interpreter 170 : EngineKind::JIT); 171 172 // If we are supposed to override the target triple, do so now. 173 if (!TargetTriple.empty()) 174 Mod->setTargetTriple(Triple::normalize(TargetTriple)); 175 176 // Enable MCJIT, if desired. 177 if (UseMCJIT) 178 builder.setUseMCJIT(true); 179 180 CodeGenOpt::Level OLvl = CodeGenOpt::Default; 181 switch (OptLevel) { 182 default: 183 errs() << argv[0] << ": invalid optimization level.\n"; 184 return 1; 185 case ' ': break; 186 case '0': OLvl = CodeGenOpt::None; break; 187 case '1': OLvl = CodeGenOpt::Less; break; 188 case '2': OLvl = CodeGenOpt::Default; break; 189 case '3': OLvl = CodeGenOpt::Aggressive; break; 190 } 191 builder.setOptLevel(OLvl); 192 193 EE = builder.create(); 194 if (!EE) { 195 if (!ErrorMsg.empty()) 196 errs() << argv[0] << ": error creating EE: " << ErrorMsg << "\n"; 197 else 198 errs() << argv[0] << ": unknown error creating EE!\n"; 199 exit(1); 200 } 201 202 EE->RegisterJITEventListener(createOProfileJITEventListener()); 203 204 EE->DisableLazyCompilation(NoLazyCompilation); 205 206 // If the user specifically requested an argv[0] to pass into the program, 207 // do it now. 208 if (!FakeArgv0.empty()) { 209 InputFile = FakeArgv0; 210 } else { 211 // Otherwise, if there is a .bc suffix on the executable strip it off, it 212 // might confuse the program. 213 if (StringRef(InputFile).endswith(".bc")) 214 InputFile.erase(InputFile.length() - 3); 215 } 216 217 // Add the module's name to the start of the vector of arguments to main(). 218 InputArgv.insert(InputArgv.begin(), InputFile); 219 220 // Call the main function from M as if its signature were: 221 // int main (int argc, char **argv, const char **envp) 222 // using the contents of Args to determine argc & argv, and the contents of 223 // EnvVars to determine envp. 224 // 225 Function *EntryFn = Mod->getFunction(EntryFunc); 226 if (!EntryFn) { 227 errs() << '\'' << EntryFunc << "\' function not found in module.\n"; 228 return -1; 229 } 230 231 // If the program doesn't explicitly call exit, we will need the Exit 232 // function later on to make an explicit call, so get the function now. 233 Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context), 234 Type::getInt32Ty(Context), 235 NULL); 236 237 // Reset errno to zero on entry to main. 238 errno = 0; 239 240 // Run static constructors. 241 EE->runStaticConstructorsDestructors(false); 242 243 if (NoLazyCompilation) { 244 for (Module::iterator I = Mod->begin(), E = Mod->end(); I != E; ++I) { 245 Function *Fn = &*I; 246 if (Fn != EntryFn && !Fn->isDeclaration()) 247 EE->getPointerToFunction(Fn); 248 } 249 } 250 251 // Run main. 252 int Result = EE->runFunctionAsMain(EntryFn, InputArgv, envp); 253 254 // Run static destructors. 255 EE->runStaticConstructorsDestructors(true); 256 257 // If the program didn't call exit explicitly, we should call it now. 258 // This ensures that any atexit handlers get called correctly. 259 if (Function *ExitF = dyn_cast<Function>(Exit)) { 260 std::vector<GenericValue> Args; 261 GenericValue ResultGV; 262 ResultGV.IntVal = APInt(32, Result); 263 Args.push_back(ResultGV); 264 EE->runFunction(ExitF, Args); 265 errs() << "ERROR: exit(" << Result << ") returned!\n"; 266 abort(); 267 } else { 268 errs() << "ERROR: exit defined with wrong prototype!\n"; 269 abort(); 270 } 271 } 272