1 //===- lli.cpp - LLVM Interpreter / Dynamic compiler ----------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // 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/Bitcode/ReaderWriter.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/ManagedStatic.h"
26 #include "llvm/Support/MemoryBuffer.h"
27 #include "llvm/Support/PluginLoader.h"
28 #include "llvm/System/Process.h"
29 #include "llvm/System/Signals.h"
36 InputFile(cl::desc("<input bitcode>"), 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 cl::opt<bool> Fast("fast",
46 cl::desc("Generate code quickly, "
47 "potentially sacrificing code quality"),
51 TargetTriple("mtriple", cl::desc("Override target triple for module"));
54 FakeArgv0("fake-argv0",
55 cl::desc("Override the 'argv[0]' value passed into the executing"
56 " program"), cl::value_desc("executable"));
59 DisableCoreFiles("disable-core-files", cl::Hidden,
60 cl::desc("Disable emission of core files if possible"));
63 NoLazyCompilation("disable-lazy-compilation",
64 cl::desc("Disable JIT lazy compilation"),
68 static ExecutionEngine *EE = 0;
70 static void do_shutdown() {
75 //===----------------------------------------------------------------------===//
76 // main Driver function
78 int main(int argc, char **argv, char * const *envp) {
79 atexit(do_shutdown); // Call llvm_shutdown() on exit.
80 cl::ParseCommandLineOptions(argc, argv,
81 "llvm interpreter & dynamic compiler\n");
82 sys::PrintStackTraceOnErrorSignal();
84 // If the user doesn't want core files, disable them.
86 sys::Process::PreventCoreFiles();
88 // Load the bitcode...
90 ModuleProvider *MP = NULL;
91 if (MemoryBuffer *Buffer = MemoryBuffer::getFileOrSTDIN(InputFile,&ErrorMsg)) {
92 MP = getBitcodeModuleProvider(Buffer, &ErrorMsg);
93 if (!MP) delete Buffer;
97 std::cerr << argv[0] << ": error loading program '" << InputFile << "': "
102 // Get the module as the MP could go away once EE takes over.
103 Module *Mod = NoLazyCompilation
104 ? MP->materializeModule(&ErrorMsg) : MP->getModule();
106 std::cerr << argv[0] << ": bitcode didn't read correctly.\n";
107 std::cerr << "Reason: " << ErrorMsg << "\n";
111 // If we are supposed to override the target triple, do so now.
112 if (!TargetTriple.empty())
113 Mod->setTargetTriple(TargetTriple);
115 EE = ExecutionEngine::create(MP, ForceInterpreter, &ErrorMsg, Fast);
116 if (!EE && !ErrorMsg.empty()) {
117 std::cerr << argv[0] << ":error creating EE: " << ErrorMsg << "\n";
121 if (NoLazyCompilation)
122 EE->DisableLazyCompilation();
124 // If the user specifically requested an argv[0] to pass into the program,
126 if (!FakeArgv0.empty()) {
127 InputFile = FakeArgv0;
129 // Otherwise, if there is a .bc suffix on the executable strip it off, it
130 // might confuse the program.
131 if (InputFile.rfind(".bc") == InputFile.length() - 3)
132 InputFile.erase(InputFile.length() - 3);
135 // Add the module's name to the start of the vector of arguments to main().
136 InputArgv.insert(InputArgv.begin(), InputFile);
138 // Call the main function from M as if its signature were:
139 // int main (int argc, char **argv, const char **envp)
140 // using the contents of Args to determine argc & argv, and the contents of
141 // EnvVars to determine envp.
143 Function *MainFn = Mod->getFunction("main");
145 std::cerr << "'main' function not found in module.\n";
149 // If the program doesn't explicitly call exit, we will need the Exit
150 // function later on to make an explicit call, so get the function now.
151 Constant *Exit = Mod->getOrInsertFunction("exit", Type::VoidTy,
152 Type::Int32Ty, NULL);
154 // Reset errno to zero on entry to main.
157 // Run static constructors.
158 EE->runStaticConstructorsDestructors(false);
160 if (NoLazyCompilation) {
161 for (Module::iterator I = Mod->begin(), E = Mod->end(); I != E; ++I) {
163 if (Fn != MainFn && !Fn->isDeclaration())
164 EE->getPointerToFunction(Fn);
169 int Result = EE->runFunctionAsMain(MainFn, InputArgv, envp);
171 // Run static destructors.
172 EE->runStaticConstructorsDestructors(true);
174 // If the program didn't call exit explicitly, we should call it now.
175 // This ensures that any atexit handlers get called correctly.
176 if (Function *ExitF = dyn_cast<Function>(Exit)) {
177 std::vector<GenericValue> Args;
178 GenericValue ResultGV;
179 ResultGV.IntVal = APInt(32, Result);
180 Args.push_back(ResultGV);
181 EE->runFunction(ExitF, Args);
182 std::cerr << "ERROR: exit(" << Result << ") returned!\n";
185 std::cerr << "ERROR: exit defined with wrong prototype!\n";