1//===- TableGenBackend.cpp - Utilities for TableGen Backends ----*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file provides useful services for TableGen backends...
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/ADT/Twine.h"
15#include "llvm/Support/raw_ostream.h"
16#include "llvm/TableGen/TableGenBackend.h"
17#include <algorithm>
18
19using namespace llvm;
20
21const size_t MAX_LINE_LEN = 80U;
22
23static void printLine(raw_ostream &OS, const Twine &Prefix, char Fill,
24                      StringRef Suffix) {
25  size_t Pos = (size_t)OS.tell();
26  assert((MAX_LINE_LEN - Prefix.str().size() - Suffix.size() > 0) &&
27    "header line exceeds max limit");
28  OS << Prefix;
29  const size_t e = MAX_LINE_LEN - Suffix.size();
30  for (size_t i = (size_t)OS.tell() - Pos; i < e; ++i)
31    OS << Fill;
32  OS << Suffix << '\n';
33}
34
35void llvm::emitSourceFileHeader(StringRef Desc, raw_ostream &OS) {
36  printLine(OS, "/*===- TableGen'erated file ", '-', "*- C++ -*-===*\\");
37  printLine(OS, "|*", ' ', "*|");
38  size_t Pos = 0U;
39  size_t PosE;
40  StringRef Prefix("|*");
41  StringRef Suffix(" *|");
42  do{
43    size_t PSLen = Suffix.size() + Prefix.size();
44    PosE = Pos + ((MAX_LINE_LEN > (Desc.size() - PSLen)) ?
45      Desc.size() :
46      MAX_LINE_LEN - PSLen);
47    printLine(OS, Prefix + Desc.slice(Pos, PosE), ' ', Suffix);
48    Pos = PosE;
49  } while(Pos < Desc.size());
50  printLine(OS, Prefix, ' ', Suffix);
51  printLine(OS, Prefix + " Automatically generated file, do not edit!", ' ',
52    Suffix);
53  printLine(OS, Prefix, ' ', Suffix);
54  printLine(OS, "\\*===", '-', "===*/");
55  OS << '\n';
56}
57