llvm-6502/tools/lli/lli.cpp
Jim Grosbach 31649e61bc Beginnings of MC-JIT code generation.
Proof-of-concept code that code-gens a module to an in-memory MachO object.
This will be hooked up to a run-time dynamic linker library (see: llvm-rtdyld
for similarly conceptual work for that part) which will take the compiled
object and link it together with the rest of the system, providing back to the
JIT a table of available symbols which will be used to respond to the
getPointerTo*() queries.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127916 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-18 22:48:41 +00:00

272 lines
8.5 KiB
C++

//===- lli.cpp - LLVM Interpreter / Dynamic compiler ----------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This utility provides a simple wrapper around the LLVM Execution Engines,
// which allow the direct execution of LLVM programs through a Just-In-Time
// compiler, or through an interpreter if no JIT is available for this platform.
//
//===----------------------------------------------------------------------===//
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/Type.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/CodeGen/LinkAllCodegenComponents.h"
#include "llvm/ExecutionEngine/GenericValue.h"
#include "llvm/ExecutionEngine/Interpreter.h"
#include "llvm/ExecutionEngine/JIT.h"
#include "llvm/ExecutionEngine/JITEventListener.h"
#include "llvm/ExecutionEngine/MCJIT.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/IRReader.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/PluginLoader.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Process.h"
#include "llvm/Support/Signals.h"
#include "llvm/Target/TargetSelect.h"
#include <cerrno>
#ifdef __CYGWIN__
#include <cygwin/version.h>
#if defined(CYGWIN_VERSION_DLL_MAJOR) && CYGWIN_VERSION_DLL_MAJOR<1007
#define DO_NOTHING_ATEXIT 1
#endif
#endif
using namespace llvm;
namespace {
cl::opt<std::string>
InputFile(cl::desc("<input bitcode>"), cl::Positional, cl::init("-"));
cl::list<std::string>
InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>..."));
cl::opt<bool> ForceInterpreter("force-interpreter",
cl::desc("Force interpretation: disable JIT"),
cl::init(false));
cl::opt<bool> UseMCJIT(
"use-mcjit", cl::desc("Enable use of the MC-based JIT (if available)"),
cl::init(false));
// Determine optimization level.
cl::opt<char>
OptLevel("O",
cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
"(default = '-O2')"),
cl::Prefix,
cl::ZeroOrMore,
cl::init(' '));
cl::opt<std::string>
TargetTriple("mtriple", cl::desc("Override target triple for module"));
cl::opt<std::string>
MArch("march",
cl::desc("Architecture to generate assembly for (see --version)"));
cl::opt<std::string>
MCPU("mcpu",
cl::desc("Target a specific cpu type (-mcpu=help for details)"),
cl::value_desc("cpu-name"),
cl::init(""));
cl::list<std::string>
MAttrs("mattr",
cl::CommaSeparated,
cl::desc("Target specific attributes (-mattr=help for details)"),
cl::value_desc("a1,+a2,-a3,..."));
cl::opt<std::string>
EntryFunc("entry-function",
cl::desc("Specify the entry function (default = 'main') "
"of the executable"),
cl::value_desc("function"),
cl::init("main"));
cl::opt<std::string>
FakeArgv0("fake-argv0",
cl::desc("Override the 'argv[0]' value passed into the executing"
" program"), cl::value_desc("executable"));
cl::opt<bool>
DisableCoreFiles("disable-core-files", cl::Hidden,
cl::desc("Disable emission of core files if possible"));
cl::opt<bool>
NoLazyCompilation("disable-lazy-compilation",
cl::desc("Disable JIT lazy compilation"),
cl::init(false));
}
static ExecutionEngine *EE = 0;
static void do_shutdown() {
// Cygwin-1.5 invokes DLL's dtors before atexit handler.
#ifndef DO_NOTHING_ATEXIT
delete EE;
llvm_shutdown();
#endif
}
//===----------------------------------------------------------------------===//
// main Driver function
//
int main(int argc, char **argv, char * const *envp) {
sys::PrintStackTraceOnErrorSignal();
PrettyStackTraceProgram X(argc, argv);
LLVMContext &Context = getGlobalContext();
atexit(do_shutdown); // Call llvm_shutdown() on exit.
// If we have a native target, initialize it to ensure it is linked in and
// usable by the JIT.
InitializeNativeTarget();
InitializeNativeTargetAsmPrinter();
cl::ParseCommandLineOptions(argc, argv,
"llvm interpreter & dynamic compiler\n");
// If the user doesn't want core files, disable them.
if (DisableCoreFiles)
sys::Process::PreventCoreFiles();
// Load the bitcode...
SMDiagnostic Err;
Module *Mod = ParseIRFile(InputFile, Err, Context);
if (!Mod) {
Err.Print(argv[0], errs());
return 1;
}
// If not jitting lazily, load the whole bitcode file eagerly too.
std::string ErrorMsg;
if (NoLazyCompilation) {
if (Mod->MaterializeAllPermanently(&ErrorMsg)) {
errs() << argv[0] << ": bitcode didn't read correctly.\n";
errs() << "Reason: " << ErrorMsg << "\n";
exit(1);
}
}
EngineBuilder builder(Mod);
builder.setMArch(MArch);
builder.setMCPU(MCPU);
builder.setMAttrs(MAttrs);
builder.setErrorStr(&ErrorMsg);
builder.setEngineKind(ForceInterpreter
? EngineKind::Interpreter
: EngineKind::JIT);
// If we are supposed to override the target triple, do so now.
if (!TargetTriple.empty())
Mod->setTargetTriple(Triple::normalize(TargetTriple));
// Enable MCJIT, if desired.
if (UseMCJIT)
builder.setUseMCJIT(true);
CodeGenOpt::Level OLvl = CodeGenOpt::Default;
switch (OptLevel) {
default:
errs() << argv[0] << ": invalid optimization level.\n";
return 1;
case ' ': break;
case '0': OLvl = CodeGenOpt::None; break;
case '1': OLvl = CodeGenOpt::Less; break;
case '2': OLvl = CodeGenOpt::Default; break;
case '3': OLvl = CodeGenOpt::Aggressive; break;
}
builder.setOptLevel(OLvl);
EE = builder.create();
if (!EE) {
if (!ErrorMsg.empty())
errs() << argv[0] << ": error creating EE: " << ErrorMsg << "\n";
else
errs() << argv[0] << ": unknown error creating EE!\n";
exit(1);
}
EE->RegisterJITEventListener(createOProfileJITEventListener());
EE->DisableLazyCompilation(NoLazyCompilation);
// If the user specifically requested an argv[0] to pass into the program,
// do it now.
if (!FakeArgv0.empty()) {
InputFile = FakeArgv0;
} else {
// Otherwise, if there is a .bc suffix on the executable strip it off, it
// might confuse the program.
if (StringRef(InputFile).endswith(".bc"))
InputFile.erase(InputFile.length() - 3);
}
// Add the module's name to the start of the vector of arguments to main().
InputArgv.insert(InputArgv.begin(), InputFile);
// Call the main function 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.
//
Function *EntryFn = Mod->getFunction(EntryFunc);
if (!EntryFn) {
errs() << '\'' << EntryFunc << "\' function not found in module.\n";
return -1;
}
// If the program doesn't explicitly call exit, we will need the Exit
// function later on to make an explicit call, so get the function now.
Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context),
Type::getInt32Ty(Context),
NULL);
// Reset errno to zero on entry to main.
errno = 0;
// Run static constructors.
EE->runStaticConstructorsDestructors(false);
if (NoLazyCompilation) {
for (Module::iterator I = Mod->begin(), E = Mod->end(); I != E; ++I) {
Function *Fn = &*I;
if (Fn != EntryFn && !Fn->isDeclaration())
EE->getPointerToFunction(Fn);
}
}
// Run main.
int Result = EE->runFunctionAsMain(EntryFn, InputArgv, envp);
// Run static destructors.
EE->runStaticConstructorsDestructors(true);
// If the program didn't call exit explicitly, we should call it now.
// This ensures that any atexit handlers get called correctly.
if (Function *ExitF = dyn_cast<Function>(Exit)) {
std::vector<GenericValue> Args;
GenericValue ResultGV;
ResultGV.IntVal = APInt(32, Result);
Args.push_back(ResultGV);
EE->runFunction(ExitF, Args);
errs() << "ERROR: exit(" << Result << ") returned!\n";
abort();
} else {
errs() << "ERROR: exit defined with wrong prototype!\n";
abort();
}
}