1 //===- TableGenBackend.cpp - Utilities for TableGen Backends ----*- 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 // This file provides useful services for TableGen backends... 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "llvm/TableGen/TableGenBackend.h" 14 #include "llvm/ADT/Twine.h" 15 #include "llvm/Support/raw_ostream.h" 16 #include <algorithm> 17 #include <cassert> 18 #include <cstddef> 19 20 using namespace llvm; 21 22 const size_t MAX_LINE_LEN = 80U; 23 24 namespace llvm::TableGen::Emitter { 25 ManagedStatic<cl::opt<FnT>, OptCreatorT> Action; 26 void *OptCreatorT::call() { 27 return new cl::opt<FnT>(cl::desc("Action to perform:")); 28 } 29 } // namespace llvm::TableGen::Emitter 30 31 static void printLine(raw_ostream &OS, const Twine &Prefix, char Fill, 32 StringRef Suffix) { 33 size_t Pos = (size_t)OS.tell(); 34 assert((Prefix.str().size() + Suffix.size() <= MAX_LINE_LEN) && 35 "header line exceeds max limit"); 36 OS << Prefix; 37 for (size_t i = (size_t)OS.tell() - Pos, e = MAX_LINE_LEN - Suffix.size(); 38 i < e; ++i) 39 OS << Fill; 40 OS << Suffix << '\n'; 41 } 42 43 void llvm::emitSourceFileHeader(StringRef Desc, raw_ostream &OS) { 44 printLine(OS, "/*===- TableGen'erated file ", '-', "*- C++ -*-===*\\"); 45 StringRef Prefix("|* "); 46 StringRef Suffix(" *|"); 47 printLine(OS, Prefix, ' ', Suffix); 48 size_t PSLen = Prefix.size() + Suffix.size(); 49 assert(PSLen < MAX_LINE_LEN); 50 size_t Pos = 0U; 51 do { 52 size_t Length = std::min(Desc.size() - Pos, MAX_LINE_LEN - PSLen); 53 printLine(OS, Prefix + Desc.substr(Pos, Length), ' ', Suffix); 54 Pos += Length; 55 } while (Pos < Desc.size()); 56 printLine(OS, Prefix, ' ', Suffix); 57 printLine(OS, Prefix + "Automatically generated file, do not edit!", ' ', 58 Suffix); 59 printLine(OS, Prefix, ' ', Suffix); 60 printLine(OS, "\\*===", '-', "===*/"); 61 OS << '\n'; 62 } 63