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   StringRef Id;
31   StringRef BufferIdentifier;
32   unsigned Line;
33 public:
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 
49 class CTagsEmitter {
50 private:
51   RecordKeeper &Records;
52 public:
53   CTagsEmitter(RecordKeeper &R) : Records(R) {}
54 
55   void run(raw_ostream &OS);
56 
57 private:
58   static SMLoc locate(const Record *R);
59 };
60 
61 } // End anonymous namespace.
62 
63 SMLoc CTagsEmitter::locate(const Record *R) {
64   ArrayRef<SMLoc> Locs = R->getLoc();
65   return !Locs.empty() ? Locs.front() : SMLoc();
66 }
67 
68 void 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 
89 namespace llvm {
90 
91 void EmitCTags(RecordKeeper &RK, raw_ostream &OS) { CTagsEmitter(RK).run(OS); }
92 
93 } // End llvm namespace.
94