lli.cpp revision 1f6efa3996dd1929fbc129203ce5009b620e6969
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 46using namespace llvm; 47 48namespace { 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 113static ExecutionEngine *EE = 0; 114 115static 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// 126int 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(); 136 137 cl::ParseCommandLineOptions(argc, argv, 138 "llvm interpreter & dynamic compiler\n"); 139 140 // If the user doesn't want core files, disable them. 141 if (DisableCoreFiles) 142 sys::Process::PreventCoreFiles(); 143 144 // Load the bitcode... 145 SMDiagnostic Err; 146 Module *Mod = ParseIRFile(InputFile, Err, Context); 147 if (!Mod) { 148 Err.Print(argv[0], errs()); 149 return 1; 150 } 151 152 // If not jitting lazily, load the whole bitcode file eagerly too. 153 std::string ErrorMsg; 154 if (NoLazyCompilation) { 155 if (Mod->MaterializeAllPermanently(&ErrorMsg)) { 156 errs() << argv[0] << ": bitcode didn't read correctly.\n"; 157 errs() << "Reason: " << ErrorMsg << "\n"; 158 exit(1); 159 } 160 } 161 162 EngineBuilder builder(Mod); 163 builder.setMArch(MArch); 164 builder.setMCPU(MCPU); 165 builder.setMAttrs(MAttrs); 166 builder.setErrorStr(&ErrorMsg); 167 builder.setEngineKind(ForceInterpreter 168 ? EngineKind::Interpreter 169 : EngineKind::JIT); 170 171 // If we are supposed to override the target triple, do so now. 172 if (!TargetTriple.empty()) 173 Mod->setTargetTriple(Triple::normalize(TargetTriple)); 174 175 // Enable MCJIT, if desired. 176 if (UseMCJIT) 177 builder.setUseMCJIT(true); 178 179 CodeGenOpt::Level OLvl = CodeGenOpt::Default; 180 switch (OptLevel) { 181 default: 182 errs() << argv[0] << ": invalid optimization level.\n"; 183 return 1; 184 case ' ': break; 185 case '0': OLvl = CodeGenOpt::None; break; 186 case '1': OLvl = CodeGenOpt::Less; break; 187 case '2': OLvl = CodeGenOpt::Default; break; 188 case '3': OLvl = CodeGenOpt::Aggressive; break; 189 } 190 builder.setOptLevel(OLvl); 191 192 EE = builder.create(); 193 if (!EE) { 194 if (!ErrorMsg.empty()) 195 errs() << argv[0] << ": error creating EE: " << ErrorMsg << "\n"; 196 else 197 errs() << argv[0] << ": unknown error creating EE!\n"; 198 exit(1); 199 } 200 201 EE->RegisterJITEventListener(createOProfileJITEventListener()); 202 203 EE->DisableLazyCompilation(NoLazyCompilation); 204 205 // If the user specifically requested an argv[0] to pass into the program, 206 // do it now. 207 if (!FakeArgv0.empty()) { 208 InputFile = FakeArgv0; 209 } else { 210 // Otherwise, if there is a .bc suffix on the executable strip it off, it 211 // might confuse the program. 212 if (StringRef(InputFile).endswith(".bc")) 213 InputFile.erase(InputFile.length() - 3); 214 } 215 216 // Add the module's name to the start of the vector of arguments to main(). 217 InputArgv.insert(InputArgv.begin(), InputFile); 218 219 // Call the main function from M as if its signature were: 220 // int main (int argc, char **argv, const char **envp) 221 // using the contents of Args to determine argc & argv, and the contents of 222 // EnvVars to determine envp. 223 // 224 Function *EntryFn = Mod->getFunction(EntryFunc); 225 if (!EntryFn) { 226 errs() << '\'' << EntryFunc << "\' function not found in module.\n"; 227 return -1; 228 } 229 230 // If the program doesn't explicitly call exit, we will need the Exit 231 // function later on to make an explicit call, so get the function now. 232 Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context), 233 Type::getInt32Ty(Context), 234 NULL); 235 236 // Reset errno to zero on entry to main. 237 errno = 0; 238 239 // Run static constructors. 240 EE->runStaticConstructorsDestructors(false); 241 242 if (NoLazyCompilation) { 243 for (Module::iterator I = Mod->begin(), E = Mod->end(); I != E; ++I) { 244 Function *Fn = &*I; 245 if (Fn != EntryFn && !Fn->isDeclaration()) 246 EE->getPointerToFunction(Fn); 247 } 248 } 249 250 // Run main. 251 int Result = EE->runFunctionAsMain(EntryFn, InputArgv, envp); 252 253 // Run static destructors. 254 EE->runStaticConstructorsDestructors(true); 255 256 // If the program didn't call exit explicitly, we should call it now. 257 // This ensures that any atexit handlers get called correctly. 258 if (Function *ExitF = dyn_cast<Function>(Exit)) { 259 std::vector<GenericValue> Args; 260 GenericValue ResultGV; 261 ResultGV.IntVal = APInt(32, Result); 262 Args.push_back(ResultGV); 263 EE->runFunction(ExitF, Args); 264 errs() << "ERROR: exit(" << Result << ") returned!\n"; 265 abort(); 266 } else { 267 errs() << "ERROR: exit defined with wrong prototype!\n"; 268 abort(); 269 } 270} 271