xref: /freebsd/contrib/llvm-project/llvm/lib/TableGen/TableGenBackend.cpp (revision 5f757f3ff9144b609b3c433dfd370cc6bdc191ad)
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/Path.h"
16  #include "llvm/Support/raw_ostream.h"
17  #include <algorithm>
18  #include <cassert>
19  #include <cstddef>
20  
21  using namespace llvm;
22  
23  const size_t MAX_LINE_LEN = 80U;
24  
25  namespace llvm::TableGen::Emitter {
26  ManagedStatic<cl::opt<FnT>, OptCreatorT> Action;
27  void *OptCreatorT::call() {
28    return new cl::opt<FnT>(cl::desc("Action to perform:"));
29  }
30  } // namespace llvm::TableGen::Emitter
31  
32  static void printLine(raw_ostream &OS, const Twine &Prefix, char Fill,
33                        StringRef Suffix) {
34    size_t Pos = (size_t)OS.tell();
35    assert((Prefix.str().size() + Suffix.size() <= MAX_LINE_LEN) &&
36           "header line exceeds max limit");
37    OS << Prefix;
38    for (size_t i = (size_t)OS.tell() - Pos, e = MAX_LINE_LEN - Suffix.size();
39           i < e; ++i)
40      OS << Fill;
41    OS << Suffix << '\n';
42  }
43  
44  void llvm::emitSourceFileHeader(StringRef Desc, raw_ostream &OS,
45                                  const RecordKeeper &Record) {
46    printLine(OS, "/*===- TableGen'erated file ", '-', "*- C++ -*-===*\\");
47    StringRef Prefix("|* ");
48    StringRef Suffix(" *|");
49    printLine(OS, Prefix, ' ', Suffix);
50    size_t PSLen = Prefix.size() + Suffix.size();
51    assert(PSLen < MAX_LINE_LEN);
52    size_t Pos = 0U;
53    do {
54      size_t Length = std::min(Desc.size() - Pos, MAX_LINE_LEN - PSLen);
55      printLine(OS, Prefix + Desc.substr(Pos, Length), ' ', Suffix);
56      Pos += Length;
57    } while (Pos < Desc.size());
58    printLine(OS, Prefix, ' ', Suffix);
59    printLine(OS, Prefix + "Automatically generated file, do not edit!", ' ',
60              Suffix);
61  
62    // Print the filename of source file
63    if (!Record.getInputFilename().empty())
64      printLine(
65          OS, Prefix + "From: " + sys::path::filename(Record.getInputFilename()),
66          ' ', Suffix);
67    printLine(OS, Prefix, ' ', Suffix);
68    printLine(OS, "\\*===", '-', "===*/");
69    OS << '\n';
70  }
71