1//===- CTagsEmitter.cpp - Generate ctags-compatible index ------------------===//
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 tablegen backend emits an index of definitions in ctags(1) format.
10// A helper script, utils/TableGen/tdtags, provides an easier-to-use
11// interface; run 'tdtags -H' for documentation.
12//
13//===----------------------------------------------------------------------===//
14
15#include "llvm/Support/MemoryBuffer.h"
16#include "llvm/Support/SourceMgr.h"
17#include "llvm/TableGen/Error.h"
18#include "llvm/TableGen/Record.h"
19#include "llvm/TableGen/TableGenBackend.h"
20#include <algorithm>
21#include <vector>
22using namespace llvm;
23
24#define DEBUG_TYPE "ctags-emitter"
25
26namespace {
27
28class Tag {
29private:
30  StringRef Id;
31  StringRef BufferIdentifier;
32  unsigned Line;
33public:
34  Tag(StringRef Name, const SMLoc Location) : Id(Name) {
35    const MemoryBuffer *CurMB =
36        SrcMgr.getMemoryBuffer(SrcMgr.FindBufferContainingLoc(Location));
37    BufferIdentifier = CurMB->getBufferIdentifier();
38    auto LineAndColumn = SrcMgr.getLineAndColumn(Location);
39    Line = LineAndColumn.first;
40  }
41  int operator<(const Tag &B) const {
42    return std::make_tuple(Id, BufferIdentifier, Line) < std::make_tuple(B.Id, B.BufferIdentifier, B.Line);
43  }
44  void emit(raw_ostream &OS) const {
45    OS << Id << "\t" << BufferIdentifier << "\t" << Line << "\n";
46  }
47};
48
49class CTagsEmitter {
50private:
51  RecordKeeper &Records;
52public:
53  CTagsEmitter(RecordKeeper &R) : Records(R) {}
54
55  void run(raw_ostream &OS);
56
57private:
58  static SMLoc locate(const Record *R);
59};
60
61} // End anonymous namespace.
62
63SMLoc CTagsEmitter::locate(const Record *R) {
64  ArrayRef<SMLoc> Locs = R->getLoc();
65  return !Locs.empty() ? Locs.front() : SMLoc();
66}
67
68void CTagsEmitter::run(raw_ostream &OS) {
69  const auto &Classes = Records.getClasses();
70  const auto &Defs = Records.getDefs();
71  std::vector<Tag> Tags;
72  // Collect tags.
73  Tags.reserve(Classes.size() + Defs.size());
74  for (const auto &C : Classes) {
75    Tags.push_back(Tag(C.first, locate(C.second.get())));
76    for (SMLoc FwdLoc : C.second->getForwardDeclarationLocs())
77      Tags.push_back(Tag(C.first, FwdLoc));
78  }
79  for (const auto &D : Defs)
80    Tags.push_back(Tag(D.first, locate(D.second.get())));
81  // Emit tags.
82  llvm::sort(Tags);
83  OS << "!_TAG_FILE_FORMAT\t1\t/original ctags format/\n";
84  OS << "!_TAG_FILE_SORTED\t1\t/0=unsorted, 1=sorted, 2=foldcase/\n";
85  for (const Tag &T : Tags)
86    T.emit(OS);
87}
88
89static TableGen::Emitter::OptClass<CTagsEmitter>
90    X("gen-ctags", "Generate ctags-compatible index");
91