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/SourceMgr.h"
16 #include "llvm/Support/MemoryBuffer.h"
17 #include "llvm/TableGen/Error.h"
18 #include "llvm/TableGen/Record.h"
19 #include <algorithm>
20 #include <string>
21 #include <vector>
22 using namespace llvm;
23 
24 #define DEBUG_TYPE "ctags-emitter"
25 
26 namespace {
27 
28 class Tag {
29 private:
30   const std::string *Id;
31   SMLoc Loc;
32 public:
33   Tag(const std::string &Name, const SMLoc Location)
34       : Id(&Name), Loc(Location) {}
35   int operator<(const Tag &B) const { return *Id < *B.Id; }
36   void emit(raw_ostream &OS) const {
37     const MemoryBuffer *CurMB =
38         SrcMgr.getMemoryBuffer(SrcMgr.FindBufferContainingLoc(Loc));
39     auto BufferName = CurMB->getBufferIdentifier();
40     std::pair<unsigned, unsigned> LineAndColumn = SrcMgr.getLineAndColumn(Loc);
41     OS << *Id << "\t" << BufferName << "\t" << LineAndColumn.first << "\n";
42   }
43 };
44 
45 class CTagsEmitter {
46 private:
47   RecordKeeper &Records;
48 public:
49   CTagsEmitter(RecordKeeper &R) : Records(R) {}
50 
51   void run(raw_ostream &OS);
52 
53 private:
54   static SMLoc locate(const Record *R);
55 };
56 
57 } // End anonymous namespace.
58 
59 SMLoc CTagsEmitter::locate(const Record *R) {
60   ArrayRef<SMLoc> Locs = R->getLoc();
61   return !Locs.empty() ? Locs.front() : SMLoc();
62 }
63 
64 void CTagsEmitter::run(raw_ostream &OS) {
65   const auto &Classes = Records.getClasses();
66   const auto &Defs = Records.getDefs();
67   std::vector<Tag> Tags;
68   // Collect tags.
69   Tags.reserve(Classes.size() + Defs.size());
70   for (const auto &C : Classes)
71     Tags.push_back(Tag(C.first, locate(C.second.get())));
72   for (const auto &D : Defs)
73     Tags.push_back(Tag(D.first, locate(D.second.get())));
74   // Emit tags.
75   llvm::sort(Tags);
76   OS << "!_TAG_FILE_FORMAT\t1\t/original ctags format/\n";
77   OS << "!_TAG_FILE_SORTED\t1\t/0=unsorted, 1=sorted, 2=foldcase/\n";
78   for (const Tag &T : Tags)
79     T.emit(OS);
80 }
81 
82 namespace llvm {
83 
84 void EmitCTags(RecordKeeper &RK, raw_ostream &OS) { CTagsEmitter(RK).run(OS); }
85 
86 } // End llvm namespace.
87