1 //===- lli.cpp - LLVM Interpreter / Dynamic compiler ----------------------===//
3 // The LLVM Compiler Infrastructure
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.
8 //===----------------------------------------------------------------------===//
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.
14 //===----------------------------------------------------------------------===//
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"
31 InputFile(cl::desc("<input bytecode>"), cl::Positional, cl::init("-"));
34 InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>..."));
36 cl::opt<bool> ForceInterpreter("force-interpreter",
37 cl::desc("Force interpretation: disable JIT"),
40 TargetTriple("mtriple", cl::desc("Override target triple for module"));
43 FakeArgv0("fake-argv0",
44 cl::desc("Override the 'argv[0]' value passed into the executing"
45 " program"), cl::value_desc("executable"));
48 //===----------------------------------------------------------------------===//
49 // main Driver function
51 int main(int argc, char **argv, char * const *envp) {
53 cl::ParseCommandLineOptions(argc, argv,
54 " llvm interpreter & dynamic compiler\n");
55 sys::PrintStackTraceOnErrorSignal();
57 // Load the bytecode...
59 ModuleProvider *MP = 0;
61 MP = getBytecodeModuleProvider(InputFile);
62 } catch (std::string &err) {
63 std::cerr << "Error loading program '" << InputFile << "': "
68 // If we are supposed to override the target triple, do so now.
69 if (!TargetTriple.empty())
70 MP->getModule()->setTargetTriple(TargetTriple);
72 ExecutionEngine *EE = ExecutionEngine::create(MP, ForceInterpreter);
73 assert(EE &&"Couldn't create an ExecutionEngine, not even an interpreter?");
75 // If the user specifically requested an argv[0] to pass into the program,
77 if (!FakeArgv0.empty()) {
78 InputFile = FakeArgv0;
80 // Otherwise, if there is a .bc suffix on the executable strip it off, it
81 // might confuse the program.
82 if (InputFile.rfind(".bc") == InputFile.length() - 3)
83 InputFile.erase(InputFile.length() - 3);
86 // Add the module's name to the start of the vector of arguments to main().
87 InputArgv.insert(InputArgv.begin(), InputFile);
89 // Call the main function from M as if its signature were:
90 // int main (int argc, char **argv, const char **envp)
91 // using the contents of Args to determine argc & argv, and the contents of
92 // EnvVars to determine envp.
94 Function *Fn = MP->getModule()->getMainFunction();
96 std::cerr << "'main' function not found in module.\n";
100 // Run static constructors.
101 EE->runStaticConstructorsDestructors(false);
104 int Result = EE->runFunctionAsMain(Fn, InputArgv, envp);
106 // Run static destructors.
107 EE->runStaticConstructorsDestructors(true);
109 // If the program didn't explicitly call exit, call exit now, for the
110 // program. This ensures that any atexit handlers get called correctly.
111 Function *Exit = MP->getModule()->getOrInsertFunction("exit", Type::VoidTy,
115 std::vector<GenericValue> Args;
116 GenericValue ResultGV;
117 ResultGV.IntVal = Result;
118 Args.push_back(ResultGV);
119 EE->runFunction(Exit, Args);
121 std::cerr << "ERROR: exit(" << Result << ") returned!\n";
123 } catch (const std::string& msg) {
124 std::cerr << argv[0] << ": " << msg << "\n";
126 std::cerr << argv[0] << ": Unexpected unknown exception occurred.\n";