1 //===- llvm/TableGen/TableGenBackend.h - Backend utilities ------*- C++ -*-===// 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 // Useful utilities for TableGen backends. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_TABLEGEN_TABLEGENBACKEND_H 14 #define LLVM_TABLEGEN_TABLEGENBACKEND_H 15 16 #include "llvm/ADT/STLFunctionalExtras.h" 17 #include "llvm/ADT/StringRef.h" 18 #include "llvm/TableGen/Record.h" 19 20 namespace llvm { 21 22 class RecordKeeper; 23 class raw_ostream; 24 25 namespace TableGen::Emitter { 26 using FnT = function_ref<void(const RecordKeeper &Records, raw_ostream &OS)>; 27 28 /// Creating an `Opt` object registers the command line option \p Name with 29 /// TableGen backend and associates the callback \p CB with that option. If 30 /// \p ByDefault is true, then that callback is applied by default if no 31 /// command line option was specified. 32 struct Opt { 33 Opt(StringRef Name, FnT CB, StringRef Desc, bool ByDefault = false); 34 }; 35 36 /// Convienence wrapper around `Opt` that registers `EmitterClass::run` as the 37 /// callback. 38 template <class EmitterC> class OptClass : Opt { 39 static void run(const RecordKeeper &RK, raw_ostream &OS) { 40 EmitterC(RK).run(OS); 41 } 42 43 public: 44 OptClass(StringRef Name, StringRef Desc) : Opt(Name, run, Desc) {} 45 }; 46 47 /// Apply callback for any command line option registered above. Returns false 48 /// is no callback was applied. 49 bool ApplyCallback(const RecordKeeper &Records, raw_ostream &OS); 50 51 } // namespace TableGen::Emitter 52 53 /// emitSourceFileHeader - Output an LLVM style file header to the specified 54 /// raw_ostream. 55 void emitSourceFileHeader(StringRef Desc, raw_ostream &OS, 56 const RecordKeeper &Record = RecordKeeper()); 57 58 } // namespace llvm 59 60 #endif // LLVM_TABLEGEN_TABLEGENBACKEND_H 61