llvm-6502/tools/lli/lli.cpp

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//===- lli.cpp - LLVM Interpreter / Dynamic compiler ----------------------===//
//
// This utility provides a way to execute LLVM bytecode without static
// compilation. This consists of a very simple and slow (but portable)
// interpreter, along with capability for system specific dynamic compilers. At
// runtime, the fastest (stable) execution engine is selected to run the
// program. This means the JIT compiler for the current platform if it's
// available.
//
//===----------------------------------------------------------------------===//
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/Bytecode/Reader.h"
#include "llvm/ExecutionEngine/ExecutionEngine.h"
#include "llvm/ExecutionEngine/GenericValue.h"
#include "llvm/Target/TargetMachineImpls.h"
#include "llvm/Target/TargetData.h"
#include "Support/CommandLine.h"
#include "Support/Debug.h"
namespace {
cl::opt<std::string>
InputFile(cl::desc("<input bytecode>"), cl::Positional, cl::init("-"));
cl::list<std::string>
InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>..."));
cl::opt<std::string>
MainFunction("f", cl::desc("Function to execute"), cl::init("main"),
cl::value_desc("function name"));
cl::opt<bool> TraceMode("trace", cl::desc("Enable Tracing"));
cl::opt<bool> ForceInterpreter("force-interpreter",
cl::desc("Force interpretation: disable JIT"),
cl::init(false));
}
static std::vector<std::string> makeStringVector(const char **envp) {
std::vector<std::string> rv;
for (unsigned i = 0; envp[i]; ++i)
rv.push_back(envp[i]);
return rv;
}
static void *CreateArgv(ExecutionEngine *EE,
const std::vector<std::string> &InputArgv) {
if (EE->getTargetData().getPointerSize() == 8) { // 64 bit target?
PointerTy *Result = new PointerTy[InputArgv.size()+1];
DEBUG(std::cerr << "ARGV = " << (void*)Result << "\n");
for (unsigned i = 0; i < InputArgv.size(); ++i) {
unsigned Size = InputArgv[i].size()+1;
char *Dest = new char[Size];
DEBUG(std::cerr << "ARGV[" << i << "] = " << (void*)Dest << "\n");
std::copy(InputArgv[i].begin(), InputArgv[i].end(), Dest);
Dest[Size-1] = 0;
// Endian safe: Result[i] = (PointerTy)Dest;
EE->StoreValueToMemory(PTOGV(Dest), (GenericValue*)(Result+i),
Type::LongTy);
}
Result[InputArgv.size()] = 0;
return Result;
} else { // 32 bit target?
int *Result = new int[InputArgv.size()+1];
DEBUG(std::cerr << "ARGV = " << (void*)Result << "\n");
for (unsigned i = 0; i < InputArgv.size(); ++i) {
unsigned Size = InputArgv[i].size()+1;
char *Dest = new char[Size];
DEBUG(std::cerr << "ARGV[" << i << "] = " << (void*)Dest << "\n");
std::copy(InputArgv[i].begin(), InputArgv[i].end(), Dest);
Dest[Size-1] = 0;
// Endian safe: Result[i] = (PointerTy)Dest;
EE->StoreValueToMemory(PTOGV(Dest), (GenericValue*)(Result+i),
Type::IntTy);
}
Result[InputArgv.size()] = 0; // null terminate it
return Result;
}
}
/// callAsMain - Call the function named FnName from M as if its
/// signature were int main (int argc, char **argv, const char
/// **envp), using the contents of Args to determine argc & argv, and
/// the contents of EnvVars to determine envp. Returns the result
/// from calling FnName, or -1 and prints an error msg. if the named
/// function cannot be found.
///
int callAsMain(ExecutionEngine *EE, Module *M, const std::string &FnName,
const std::vector<std::string> &Args,
const std::vector<std::string> &EnvVars) {
Function *Fn = M->getNamedFunction(FnName);
if (!Fn) {
std::cerr << "Function '" << FnName << "' not found in module.\n";
return -1;
}
std::vector<GenericValue> GVArgs;
GenericValue GVArgc;
GVArgc.IntVal = Args.size();
GVArgs.push_back(GVArgc); // Arg #0 = argc.
GVArgs.push_back(PTOGV(CreateArgv(EE, Args))); // Arg #1 = argv.
GVArgs.push_back(PTOGV(CreateArgv(EE, EnvVars))); // Arg #2 = envp.
return EE->run(Fn, GVArgs).IntVal;
}
//===----------------------------------------------------------------------===//
// main Driver function
//
int main(int argc, char **argv, const char **envp) {
cl::ParseCommandLineOptions(argc, argv,
" llvm interpreter & dynamic compiler\n");
// Load the bytecode...
std::string ErrorMsg;
Module *M = ParseBytecodeFile(InputFile, &ErrorMsg);
if (M == 0) {
std::cout << "Error parsing '" << InputFile << "': "
<< ErrorMsg << "\n";
exit(1);
}
ExecutionEngine *EE =
ExecutionEngine::create(M, ForceInterpreter, TraceMode);
assert(EE && "Couldn't create an ExecutionEngine, not even an interpreter?");
// Add the module's name to the start of the vector of arguments to main().
// But delete .bc first, since programs (and users) might not expect to
// see it.
const std::string ByteCodeFileSuffix(".bc");
if (InputFile.rfind(ByteCodeFileSuffix) ==
InputFile.length() - ByteCodeFileSuffix.length()) {
InputFile.erase(InputFile.length() - ByteCodeFileSuffix.length());
}
InputArgv.insert(InputArgv.begin(), InputFile);
// Run the main function!
int ExitCode = callAsMain(EE, M, MainFunction, InputArgv,
makeStringVector(envp));
// Now that we are done executing the program, shut down the execution engine
delete EE;
return ExitCode;
}