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Diffstat (limited to 'clang/examples/clang-interpreter/main.cpp')
-rw-r--r-- | clang/examples/clang-interpreter/main.cpp | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/clang/examples/clang-interpreter/main.cpp b/clang/examples/clang-interpreter/main.cpp new file mode 100644 index 0000000..c39468a --- /dev/null +++ b/clang/examples/clang-interpreter/main.cpp @@ -0,0 +1,156 @@ +//===-- 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/CodeGen/CodeGenAction.h" +#include "clang/Driver/Compilation.h" +#include "clang/Driver/Driver.h" +#include "clang/Driver/Tool.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/Module.h" +#include "llvm/ADT/OwningPtr.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ExecutionEngine/JIT.h" +#include "llvm/ExecutionEngine/ExecutionEngine.h" +#include "llvm/Support/ManagedStatic.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Support/Host.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/TargetSelect.h" +using namespace clang; +using namespace clang::driver; + +// This function isn't referenced outside its translation unit, but it +// can't use the "static" keyword because its address is used for +// GetMainExecutable (since some platforms don't support taking the +// address of main, and some platforms can't implement GetMainExecutable +// without being given the address of a function in the main executable). +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); +} + +static int Execute(llvm::Module *Mod, char * const *envp) { + llvm::InitializeNativeTarget(); + + std::string Error; + 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; + Args.push_back(Mod->getModuleIdentifier()); + + 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 = + new TextDiagnosticPrinter(llvm::errs(), DiagnosticOptions()); + + IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs()); + DiagnosticsEngine Diags(DiagID, DiagClient); + Driver TheDriver(Path.str(), llvm::sys::getDefaultTargetTriple(), + "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); + Args.push_back("-fsyntax-only"); + OwningPtr<Compilation> C(TheDriver.BuildCompilation(Args)); + 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())) { + 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") { + Diags.Report(diag::err_fe_expected_clang_command); + return 1; + } + + // Initialize a compiler invocation object from the clang (-cc1) arguments. + const driver::ArgStringList &CCArgs = Cmd->getArguments(); + OwningPtr<CompilerInvocation> CI(new CompilerInvocation); + CompilerInvocation::CreateFromArgs(*CI, + const_cast<const char **>(CCArgs.data()), + const_cast<const char **>(CCArgs.data()) + + CCArgs.size(), + Diags); + + // 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.setInvocation(CI.take()); + + // Create the compilers actual diagnostics engine. + Clang.createDiagnostics(int(CCArgs.size()),const_cast<char**>(CCArgs.data())); + if (!Clang.hasDiagnostics()) + return 1; + + // Infer the builtin include path if unspecified. + if (Clang.getHeaderSearchOpts().UseBuiltinIncludes && + Clang.getHeaderSearchOpts().ResourceDir.empty()) + Clang.getHeaderSearchOpts().ResourceDir = + CompilerInvocation::GetResourcesPath(argv[0], MainAddr); + + // Create and execute the frontend to generate an LLVM bitcode module. + 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. + + llvm::llvm_shutdown(); + + return Res; +} |