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 17 using namespace llvm; 18 19 const size_t MAX_LINE_LEN = 80U; 20 21 static void printLine(raw_ostream &OS, const Twine &Prefix, char Fill, 22 StringRef Suffix) { 23 size_t Pos = (size_t)OS.tell(); 24 assert((Prefix.str().size() + Suffix.size() <= MAX_LINE_LEN) && 25 "header line exceeds max limit"); 26 OS << Prefix; 27 for (size_t i = (size_t)OS.tell() - Pos, e = MAX_LINE_LEN - Suffix.size(); 28 i < e; ++i) 29 OS << Fill; 30 OS << Suffix << '\n'; 31 } 32 33 void llvm::emitSourceFileHeader(StringRef Desc, raw_ostream &OS) { 34 printLine(OS, "/*===- TableGen'erated file ", '-', "*- C++ -*-===*\\"); 35 StringRef Prefix("|* "); 36 StringRef Suffix(" *|"); 37 printLine(OS, Prefix, ' ', Suffix); 38 size_t PSLen = Prefix.size() + Suffix.size(); 39 assert(PSLen < MAX_LINE_LEN); 40 size_t Pos = 0U; 41 do { 42 size_t Length = std::min(Desc.size() - Pos, MAX_LINE_LEN - PSLen); 43 printLine(OS, Prefix + Desc.substr(Pos, Length), ' ', Suffix); 44 Pos += Length; 45 } while (Pos < Desc.size()); 46 printLine(OS, Prefix, ' ', Suffix); 47 printLine(OS, Prefix + "Automatically generated file, do not edit!", ' ', 48 Suffix); 49 printLine(OS, Prefix, ' ', Suffix); 50 printLine(OS, "\\*===", '-', "===*/"); 51 OS << '\n'; 52 } 53