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/CodeGen/LinkAllCodegenComponents.h"
21 #include "llvm/ExecutionEngine/JIT.h"
22 #include "llvm/ExecutionEngine/Interpreter.h"
23 #include "llvm/ExecutionEngine/GenericValue.h"
24 #include "llvm/Support/CommandLine.h"
25 #include "llvm/Support/Compressor.h"
26 #include "llvm/Support/ManagedStatic.h"
27 #include "llvm/Support/PluginLoader.h"
28 #include "llvm/System/Process.h"
29 #include "llvm/System/Signals.h"
36 InputFile(cl::desc("<input bytecode>"), cl::Positional, cl::init("-"));
39 InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>..."));
41 cl::opt<bool> ForceInterpreter("force-interpreter",
42 cl::desc("Force interpretation: disable JIT"),
45 TargetTriple("mtriple", cl::desc("Override target triple for module"));
48 FakeArgv0("fake-argv0",
49 cl::desc("Override the 'argv[0]' value passed into the executing"
50 " program"), cl::value_desc("executable"));
53 DisableCoreFiles("disable-core-files", cl::Hidden,
54 cl::desc("Disable emission of core files if possible"));
57 static ExecutionEngine *EE = 0;
59 static void do_shutdown() {
64 //===----------------------------------------------------------------------===//
65 // main Driver function
67 int main(int argc, char **argv, char * const *envp) {
68 atexit(do_shutdown); // Call llvm_shutdown() on exit.
70 cl::ParseCommandLineOptions(argc, argv,
71 " llvm interpreter & dynamic compiler\n");
72 sys::PrintStackTraceOnErrorSignal();
74 // If the user doesn't want core files, disable them.
76 sys::Process::PreventCoreFiles();
78 // Load the bytecode...
80 ModuleProvider *MP = getBytecodeModuleProvider(InputFile,
81 Compressor::decompressToNewBuffer,
84 std::cerr << argv[0] << ": error loading program '" << InputFile << "': "
89 // Get the module as the MP could go away once EE takes over.
90 Module *Mod = MP->getModule();
92 // If we are supposed to override the target triple, do so now.
93 if (!TargetTriple.empty())
94 Mod->setTargetTriple(TargetTriple);
96 EE = ExecutionEngine::create(MP, ForceInterpreter, &ErrorMsg);
97 if (!EE && !ErrorMsg.empty()) {
98 std::cerr << argv[0] << ":error creating EE: " << ErrorMsg << "\n";
102 // If the user specifically requested an argv[0] to pass into the program,
104 if (!FakeArgv0.empty()) {
105 InputFile = FakeArgv0;
107 // Otherwise, if there is a .bc suffix on the executable strip it off, it
108 // might confuse the program.
109 if (InputFile.rfind(".bc") == InputFile.length() - 3)
110 InputFile.erase(InputFile.length() - 3);
113 // Add the module's name to the start of the vector of arguments to main().
114 InputArgv.insert(InputArgv.begin(), InputFile);
116 // Call the main function from M as if its signature were:
117 // int main (int argc, char **argv, const char **envp)
118 // using the contents of Args to determine argc & argv, and the contents of
119 // EnvVars to determine envp.
121 Function *Fn = Mod->getFunction("main");
123 std::cerr << "'main' function not found in module.\n";
127 // If the program doesn't explicitly call exit, we will need the Exit
128 // function later on to make an explicit call, so get the function now.
129 Constant *Exit = Mod->getOrInsertFunction("exit", Type::VoidTy,
130 Type::Int32Ty, NULL);
131 // Run static constructors.
132 EE->runStaticConstructorsDestructors(false);
135 int Result = EE->runFunctionAsMain(Fn, InputArgv, envp);
137 // Run static destructors.
138 EE->runStaticConstructorsDestructors(true);
140 // If the program didn't call exit explicitly, we should call it now.
141 // This ensures that any atexit handlers get called correctly.
142 if (Function *ExitF = dyn_cast<Function>(Exit)) {
143 std::vector<GenericValue> Args;
144 GenericValue ResultGV;
145 ResultGV.IntVal = APInt(32, Result);
146 Args.push_back(ResultGV);
147 EE->runFunction(ExitF, Args);
148 std::cerr << "ERROR: exit(" << Result << ") returned!\n";
151 std::cerr << "ERROR: exit defined with wrong prototype!\n";
154 } catch (const std::string& msg) {
155 std::cerr << argv[0] << ": " << msg << "\n";
157 std::cerr << argv[0] << ": Unexpected unknown exception occurred.\n";