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/ModuleProvider.h" 19 #include "llvm/Type.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/Support/CommandLine.h" 27 #include "llvm/Support/ManagedStatic.h" 28 #include "llvm/Support/MemoryBuffer.h" 29 #include "llvm/Support/PluginLoader.h" 30 #include "llvm/Support/PrettyStackTrace.h" 31 #include "llvm/System/Process.h" 32 #include "llvm/System/Signals.h" 33 #include "llvm/Target/TargetSelect.h" 34 #include <iostream> 35 #include <cerrno> 36 using namespace llvm; 37 38 namespace { 39 cl::opt<std::string> 40 InputFile(cl::desc("<input bitcode>"), cl::Positional, cl::init("-")); 41 42 cl::list<std::string> 43 InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>...")); 44 45 cl::opt<bool> ForceInterpreter("force-interpreter", 46 cl::desc("Force interpretation: disable JIT"), 47 cl::init(false)); 48 49 // Determine optimization level. 50 cl::opt<char> 51 OptLevel("O", 52 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] " 53 "(default = '-O2')"), 54 cl::Prefix, 55 cl::ZeroOrMore, 56 cl::init(' ')); 57 58 cl::opt<std::string> 59 TargetTriple("mtriple", cl::desc("Override target triple for module")); 60 61 cl::opt<std::string> 62 EntryFunc("entry-function", 63 cl::desc("Specify the entry function (default = 'main') " 64 "of the executable"), 65 cl::value_desc("function"), 66 cl::init("main")); 67 68 cl::opt<std::string> 69 FakeArgv0("fake-argv0", 70 cl::desc("Override the 'argv[0]' value passed into the executing" 71 " program"), cl::value_desc("executable")); 72 73 cl::opt<bool> 74 DisableCoreFiles("disable-core-files", cl::Hidden, 75 cl::desc("Disable emission of core files if possible")); 76 77 cl::opt<bool> 78 NoLazyCompilation("disable-lazy-compilation", 79 cl::desc("Disable JIT lazy compilation"), 80 cl::init(false)); 81 } 82 83 static ExecutionEngine *EE = 0; 84 85 static void do_shutdown() { 86 delete EE; 87 llvm_shutdown(); 88 } 89 90 //===----------------------------------------------------------------------===// 91 // main Driver function 92 // 93 int main(int argc, char **argv, char * const *envp) { 94 sys::PrintStackTraceOnErrorSignal(); 95 PrettyStackTraceProgram X(argc, argv); 96 97 LLVMContext &Context = getGlobalContext(); 98 atexit(do_shutdown); // Call llvm_shutdown() on exit. 99 100 // If we have a native target, initialize it to ensure it is linked in and 101 // usable by the JIT. 102 InitializeNativeTarget(); 103 104 cl::ParseCommandLineOptions(argc, argv, 105 "llvm interpreter & dynamic compiler\n"); 106 107 // If the user doesn't want core files, disable them. 108 if (DisableCoreFiles) 109 sys::Process::PreventCoreFiles(); 110 111 // Load the bitcode... 112 std::string ErrorMsg; 113 ModuleProvider *MP = NULL; 114 if (MemoryBuffer *Buffer = MemoryBuffer::getFileOrSTDIN(InputFile,&ErrorMsg)){ 115 MP = getBitcodeModuleProvider(Buffer, Context, &ErrorMsg); 116 if (!MP) delete Buffer; 117 } 118 119 if (!MP) { 120 errs() << argv[0] << ": error loading program '" << InputFile << "': " 121 << ErrorMsg << "\n"; 122 exit(1); 123 } 124 125 // Get the module as the MP could go away once EE takes over. 126 Module *Mod = NoLazyCompilation 127 ? MP->materializeModule(&ErrorMsg) : MP->getModule(); 128 if (!Mod) { 129 errs() << argv[0] << ": bitcode didn't read correctly.\n"; 130 errs() << "Reason: " << ErrorMsg << "\n"; 131 exit(1); 132 } 133 134 EngineBuilder builder(MP); 135 builder.setErrorStr(&ErrorMsg); 136 builder.setEngineKind(ForceInterpreter 137 ? EngineKind::Interpreter 138 : EngineKind::JIT); 139 140 // If we are supposed to override the target triple, do so now. 141 if (!TargetTriple.empty()) 142 Mod->setTargetTriple(TargetTriple); 143 144 CodeGenOpt::Level OLvl = CodeGenOpt::Default; 145 switch (OptLevel) { 146 default: 147 errs() << argv[0] << ": invalid optimization level.\n"; 148 return 1; 149 case ' ': break; 150 case '0': OLvl = CodeGenOpt::None; break; 151 case '1': 152 case '2': OLvl = CodeGenOpt::Default; break; 153 case '3': OLvl = CodeGenOpt::Aggressive; break; 154 } 155 builder.setOptLevel(OLvl); 156 157 EE = builder.create(); 158 if (!EE) { 159 if (!ErrorMsg.empty()) 160 errs() << argv[0] << ": error creating EE: " << ErrorMsg << "\n"; 161 else 162 errs() << argv[0] << ": unknown error creating EE!\n"; 163 exit(1); 164 } 165 166 EE->RegisterJITEventListener(createMacOSJITEventListener()); 167 EE->RegisterJITEventListener(createOProfileJITEventListener()); 168 169 if (NoLazyCompilation) 170 EE->DisableLazyCompilation(); 171 172 // If the user specifically requested an argv[0] to pass into the program, 173 // do it now. 174 if (!FakeArgv0.empty()) { 175 InputFile = FakeArgv0; 176 } else { 177 // Otherwise, if there is a .bc suffix on the executable strip it off, it 178 // might confuse the program. 179 if (InputFile.rfind(".bc") == InputFile.length() - 3) 180 InputFile.erase(InputFile.length() - 3); 181 } 182 183 // Add the module's name to the start of the vector of arguments to main(). 184 InputArgv.insert(InputArgv.begin(), InputFile); 185 186 // Call the main function from M as if its signature were: 187 // int main (int argc, char **argv, const char **envp) 188 // using the contents of Args to determine argc & argv, and the contents of 189 // EnvVars to determine envp. 190 // 191 Function *EntryFn = Mod->getFunction(EntryFunc); 192 if (!EntryFn) { 193 errs() << '\'' << EntryFunc << "\' function not found in module.\n"; 194 return -1; 195 } 196 197 // If the program doesn't explicitly call exit, we will need the Exit 198 // function later on to make an explicit call, so get the function now. 199 Constant *Exit = Mod->getOrInsertFunction("exit", Type::VoidTy, 200 Type::Int32Ty, NULL); 201 202 // Reset errno to zero on entry to main. 203 errno = 0; 204 205 // Run static constructors. 206 EE->runStaticConstructorsDestructors(false); 207 208 if (NoLazyCompilation) { 209 for (Module::iterator I = Mod->begin(), E = Mod->end(); I != E; ++I) { 210 Function *Fn = &*I; 211 if (Fn != EntryFn && !Fn->isDeclaration()) 212 EE->getPointerToFunction(Fn); 213 } 214 } 215 216 // Run main. 217 int Result = EE->runFunctionAsMain(EntryFn, InputArgv, envp); 218 219 // Run static destructors. 220 EE->runStaticConstructorsDestructors(true); 221 222 // If the program didn't call exit explicitly, we should call it now. 223 // This ensures that any atexit handlers get called correctly. 224 if (Function *ExitF = dyn_cast<Function>(Exit)) { 225 std::vector<GenericValue> Args; 226 GenericValue ResultGV; 227 ResultGV.IntVal = APInt(32, Result); 228 Args.push_back(ResultGV); 229 EE->runFunction(ExitF, Args); 230 errs() << "ERROR: exit(" << Result << ") returned!\n"; 231 abort(); 232 } else { 233 errs() << "ERROR: exit defined with wrong prototype!\n"; 234 abort(); 235 } 236 } 237