1 //===--- tools/clang-repl/ClangRepl.cpp - clang-repl - the Clang REPL -----===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file implements a REPL tool on top of clang. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "clang/Basic/Diagnostic.h" 14 #include "clang/Frontend/CompilerInstance.h" 15 #include "clang/Frontend/FrontendDiagnostic.h" 16 #include "clang/Interpreter/Interpreter.h" 17 18 #include "llvm/ExecutionEngine/Orc/LLJIT.h" 19 #include "llvm/LineEditor/LineEditor.h" 20 #include "llvm/Support/CommandLine.h" 21 #include "llvm/Support/ManagedStatic.h" // llvm_shutdown 22 #include "llvm/Support/Signals.h" 23 #include "llvm/Support/TargetSelect.h" // llvm::Initialize* 24 25 static llvm::cl::list<std::string> 26 ClangArgs("Xcc", 27 llvm::cl::desc("Argument to pass to the CompilerInvocation"), 28 llvm::cl::CommaSeparated); 29 static llvm::cl::opt<bool> OptHostSupportsJit("host-supports-jit", 30 llvm::cl::Hidden); 31 static llvm::cl::list<std::string> OptInputs(llvm::cl::Positional, 32 llvm::cl::desc("[code to run]")); 33 34 static void LLVMErrorHandler(void *UserData, const char *Message, 35 bool GenCrashDiag) { 36 auto &Diags = *static_cast<clang::DiagnosticsEngine *>(UserData); 37 38 Diags.Report(clang::diag::err_fe_error_backend) << Message; 39 40 // Run the interrupt handlers to make sure any special cleanups get done, in 41 // particular that we remove files registered with RemoveFileOnSignal. 42 llvm::sys::RunInterruptHandlers(); 43 44 // We cannot recover from llvm errors. When reporting a fatal error, exit 45 // with status 70 to generate crash diagnostics. For BSD systems this is 46 // defined as an internal software error. Otherwise, exit with status 1. 47 48 exit(GenCrashDiag ? 70 : 1); 49 } 50 51 // If we are running with -verify a reported has to be returned as unsuccess. 52 // This is relevant especially for the test suite. 53 static int checkDiagErrors(const clang::CompilerInstance *CI) { 54 unsigned Errs = CI->getDiagnostics().getClient()->getNumErrors(); 55 if (CI->getDiagnosticOpts().VerifyDiagnostics) { 56 // If there was an error that came from the verifier we must return 1 as 57 // an exit code for the process. This will make the test fail as expected. 58 clang::DiagnosticConsumer *Client = CI->getDiagnostics().getClient(); 59 Client->EndSourceFile(); 60 Errs = Client->getNumErrors(); 61 62 // The interpreter expects BeginSourceFile/EndSourceFiles to be balanced. 63 Client->BeginSourceFile(CI->getLangOpts(), &CI->getPreprocessor()); 64 } 65 return Errs ? EXIT_FAILURE : EXIT_SUCCESS; 66 } 67 68 llvm::ExitOnError ExitOnErr; 69 int main(int argc, const char **argv) { 70 ExitOnErr.setBanner("clang-repl: "); 71 llvm::cl::ParseCommandLineOptions(argc, argv); 72 73 std::vector<const char *> ClangArgv(ClangArgs.size()); 74 std::transform(ClangArgs.begin(), ClangArgs.end(), ClangArgv.begin(), 75 [](const std::string &s) -> const char * { return s.data(); }); 76 llvm::InitializeNativeTarget(); 77 llvm::InitializeNativeTargetAsmPrinter(); 78 79 if (OptHostSupportsJit) { 80 auto J = llvm::orc::LLJITBuilder().create(); 81 if (J) 82 llvm::outs() << "true\n"; 83 else { 84 llvm::consumeError(J.takeError()); 85 llvm::outs() << "false\n"; 86 } 87 return 0; 88 } 89 90 // FIXME: Investigate if we could use runToolOnCodeWithArgs from tooling. It 91 // can replace the boilerplate code for creation of the compiler instance. 92 auto CI = ExitOnErr(clang::IncrementalCompilerBuilder::create(ClangArgv)); 93 94 // Set an error handler, so that any LLVM backend diagnostics go through our 95 // error handler. 96 llvm::install_fatal_error_handler(LLVMErrorHandler, 97 static_cast<void *>(&CI->getDiagnostics())); 98 99 // Load any requested plugins. 100 CI->LoadRequestedPlugins(); 101 102 auto Interp = ExitOnErr(clang::Interpreter::create(std::move(CI))); 103 for (const std::string &input : OptInputs) { 104 if (auto Err = Interp->ParseAndExecute(input)) 105 llvm::logAllUnhandledErrors(std::move(Err), llvm::errs(), "error: "); 106 } 107 108 if (OptInputs.empty()) { 109 llvm::LineEditor LE("clang-repl"); 110 // FIXME: Add LE.setListCompleter 111 while (llvm::Optional<std::string> Line = LE.readLine()) { 112 if (*Line == R"(%quit)") 113 break; 114 if (*Line == R"(%undo)") { 115 if (auto Err = Interp->Undo()) 116 llvm::logAllUnhandledErrors(std::move(Err), llvm::errs(), "error: "); 117 continue; 118 } 119 120 if (auto Err = Interp->ParseAndExecute(*Line)) 121 llvm::logAllUnhandledErrors(std::move(Err), llvm::errs(), "error: "); 122 } 123 } 124 125 // Our error handler depends on the Diagnostics object, which we're 126 // potentially about to delete. Uninstall the handler now so that any 127 // later errors use the default handling behavior instead. 128 llvm::remove_fatal_error_handler(); 129 130 llvm::llvm_shutdown(); 131 132 return checkDiagErrors(Interp->getCompilerInstance()); 133 } 134