lli.cpp revision 551ccae044b0ff658fe629dd67edd5ffe75d10e8
1//===- lli.cpp - LLVM Interpreter / Dynamic compiler ----------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by the LLVM research group and is distributed under 6// the University of Illinois Open Source 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 intepreter if no JIT is available for this platform. 13// 14//===----------------------------------------------------------------------===// 15 16#include "llvm/Module.h" 17#include "llvm/ModuleProvider.h" 18#include "llvm/Type.h" 19#include "llvm/Bytecode/Reader.h" 20#include "llvm/ExecutionEngine/ExecutionEngine.h" 21#include "llvm/ExecutionEngine/GenericValue.h" 22#include "llvm/Support/CommandLine.h" 23#include "llvm/Support/PluginLoader.h" 24#include "llvm/System/Signals.h" 25#include <iostream> 26 27using namespace llvm; 28 29namespace { 30 cl::opt<std::string> 31 InputFile(cl::desc("<input bytecode>"), cl::Positional, cl::init("-")); 32 33 cl::list<std::string> 34 InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>...")); 35 36 cl::opt<bool> ForceInterpreter("force-interpreter", 37 cl::desc("Force interpretation: disable JIT"), 38 cl::init(false)); 39 40 cl::opt<std::string> 41 FakeArgv0("fake-argv0", 42 cl::desc("Override the 'argv[0]' value passed into the executing" 43 " program"), cl::value_desc("executable")); 44} 45 46//===----------------------------------------------------------------------===// 47// main Driver function 48// 49int main(int argc, char **argv, char * const *envp) { 50 cl::ParseCommandLineOptions(argc, argv, 51 " llvm interpreter & dynamic compiler\n"); 52 sys::PrintStackTraceOnErrorSignal(); 53 54 // Load the bytecode... 55 std::string ErrorMsg; 56 ModuleProvider *MP = 0; 57 try { 58 MP = getBytecodeModuleProvider(InputFile); 59 } catch (std::string &err) { 60 std::cerr << "Error loading program '" << InputFile << "': " << err << "\n"; 61 exit(1); 62 } 63 64 ExecutionEngine *EE = ExecutionEngine::create(MP, ForceInterpreter); 65 assert(EE && "Couldn't create an ExecutionEngine, not even an interpreter?"); 66 67 // If the user specifically requested an argv[0] to pass into the program, do 68 // it now. 69 if (!FakeArgv0.empty()) { 70 InputFile = FakeArgv0; 71 } else { 72 // Otherwise, if there is a .bc suffix on the executable strip it off, it 73 // might confuse the program. 74 if (InputFile.rfind(".bc") == InputFile.length() - 3) 75 InputFile.erase(InputFile.length() - 3); 76 } 77 78 // Add the module's name to the start of the vector of arguments to main(). 79 InputArgv.insert(InputArgv.begin(), InputFile); 80 81 // Call the main function from M as if its signature were: 82 // int main (int argc, char **argv, const char **envp) 83 // using the contents of Args to determine argc & argv, and the contents of 84 // EnvVars to determine envp. 85 // 86 Function *Fn = MP->getModule()->getMainFunction(); 87 if (!Fn) { 88 std::cerr << "'main' function not found in module.\n"; 89 return -1; 90 } 91 92 // Run main... 93 int Result = EE->runFunctionAsMain(Fn, InputArgv, envp); 94 95 // If the program didn't explicitly call exit, call exit now, for the program. 96 // This ensures that any atexit handlers get called correctly. 97 Function *Exit = MP->getModule()->getOrInsertFunction("exit", Type::VoidTy, 98 Type::IntTy, 0); 99 100 std::vector<GenericValue> Args; 101 GenericValue ResultGV; 102 ResultGV.IntVal = Result; 103 Args.push_back(ResultGV); 104 EE->runFunction(Exit, Args); 105 106 std::cerr << "ERROR: exit(" << Result << ") returned!\n"; 107 abort(); 108} 109