blob: b739b7156bb1e35f098fc7743f659f701e60299f [file] [log] [blame]
//===-- examples/clang-interpreter/main.cpp - Clang C Interpreter Example -===//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
#include "clang/Driver/Compilation.h"
#include "clang/Driver/Driver.h"
#include "clang/Driver/Tool.h"
#include "clang/Frontend/CodeGenAction.h"
#include "clang/Frontend/CompilerInvocation.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Frontend/DiagnosticOptions.h"
#include "clang/Frontend/FrontendDiagnostic.h"
#include "clang/Frontend/TextDiagnosticPrinter.h"
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/Config/config.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Config/config.h"
#include "llvm/ExecutionEngine/ExecutionEngine.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/System/Host.h"
#include "llvm/System/Path.h"
#include "llvm/Target/TargetSelect.h"
using namespace clang;
using namespace clang::driver;
llvm::sys::Path GetExecutablePath(const char *Argv0) {
// This just needs to be some symbol in the binary; C++ doesn't
// allow taking the address of ::main however.
void *MainAddr = (void*) (intptr_t) GetExecutablePath;
return llvm::sys::Path::GetMainExecutable(Argv0, MainAddr);
int Execute(llvm::Module *Mod, char * const *envp) {
std::string Error;
llvm::OwningPtr<llvm::ExecutionEngine> EE(
llvm::ExecutionEngine::createJIT(Mod, &Error));
if (!EE) {
llvm::errs() << "unable to make execution engine: " << Error << "\n";
return 255;
llvm::Function *EntryFn = Mod->getFunction("main");
if (!EntryFn) {
llvm::errs() << "'main' function not found in module.\n";
return 255;
// FIXME: Support passing arguments.
std::vector<std::string> Args;
return EE->runFunctionAsMain(EntryFn, Args, envp);
int main(int argc, const char **argv, char * const *envp) {
void *MainAddr = (void*) (intptr_t) GetExecutablePath;
llvm::sys::Path Path = GetExecutablePath(argv[0]);
TextDiagnosticPrinter DiagClient(llvm::errs(), DiagnosticOptions());
Diagnostic Diags(&DiagClient);
Driver TheDriver(Path.getBasename(), Path.getDirname(),
"a.out", /*IsProduction=*/false, Diags);
TheDriver.setTitle("clang interpreter");
// FIXME: This is a hack to try to force the driver to do something we can
// recognize. We need to extend the driver library to support this use model
// (basically, exactly one input, and the operation mode is hard wired).
llvm::SmallVector<const char *, 16> Args(argv, argv + argc);
llvm::OwningPtr<Compilation> C(TheDriver.BuildCompilation(Args.size(),;
if (!C)
return 0;
// FIXME: This is copied from ASTUnit.cpp; simplify and eliminate.
// We expect to get back exactly one command job, if we didn't something
// failed. Extract that job from the compilation.
const driver::JobList &Jobs = C->getJobs();
if (Jobs.size() != 1 || !isa<driver::Command>(Jobs.begin())) {
llvm::SmallString<256> Msg;
llvm::raw_svector_ostream OS(Msg);
C->PrintJob(OS, C->getJobs(), "; ", true);
Diags.Report(diag::err_fe_expected_compiler_job) << OS.str();
return 1;
const driver::Command *Cmd = cast<driver::Command>(*Jobs.begin());
if (llvm::StringRef(Cmd->getCreator().getName()) != "clang") {
return 1;
// Initialize a compiler invocation object from the clang (-cc1) arguments.
const driver::ArgStringList &CCArgs = Cmd->getArguments();
llvm::OwningPtr<CompilerInvocation> CI(new CompilerInvocation);
CompilerInvocation::CreateFromArgs(*CI, (const char**),
(const char**),
// Show the invocation, with -v.
if (CI->getHeaderSearchOpts().Verbose) {
llvm::errs() << "clang invocation:\n";
C->PrintJob(llvm::errs(), C->getJobs(), "\n", true);
llvm::errs() << "\n";
// FIXME: This is copied from cc1_main.cpp; simplify and eliminate.
// Create a compiler instance to handle the actual work.
CompilerInstance Clang;
Clang.setLLVMContext(new llvm::LLVMContext);
// Create the compilers actual diagnostics engine.
Clang.createDiagnostics(int(CCArgs.size()), (char**);
if (!Clang.hasDiagnostics())
return 1;
// Infer the builtin include path if unspecified.
if (Clang.getHeaderSearchOpts().UseBuiltinIncludes &&
Clang.getHeaderSearchOpts().ResourceDir =
CompilerInvocation::GetResourcesPath(argv[0], MainAddr);
// Create and execute the frontend to generate an LLVM bitcode module.
llvm::OwningPtr<CodeGenAction> Act(new EmitLLVMOnlyAction());
if (!Clang.ExecuteAction(*Act))
return 1;
int Res = 255;
if (llvm::Module *Module = Act->takeModule())
Res = Execute(Module, envp);
// Shutdown.
return Res;