1 //===--- TokenRewriter.cpp - Token-based code rewriting interface ---------===//
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 implements the TokenRewriter class, which is used for code
11 // transformations.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "clang/Rewrite/Core/TokenRewriter.h"
16 #include "clang/Lex/Lexer.h"
17 #include "clang/Lex/ScratchBuffer.h"
18 #include "clang/Basic/SourceManager.h"
19 using namespace clang;
20
TokenRewriter(FileID FID,SourceManager & SM,const LangOptions & LangOpts)21 TokenRewriter::TokenRewriter(FileID FID, SourceManager &SM,
22 const LangOptions &LangOpts) {
23 ScratchBuf.reset(new ScratchBuffer(SM));
24
25 // Create a lexer to lex all the tokens of the main file in raw mode.
26 const llvm::MemoryBuffer *FromFile = SM.getBuffer(FID);
27 Lexer RawLex(FID, FromFile, SM, LangOpts);
28
29 // Return all comments and whitespace as tokens.
30 RawLex.SetKeepWhitespaceMode(true);
31
32 // Lex the file, populating our datastructures.
33 Token RawTok;
34 RawLex.LexFromRawLexer(RawTok);
35 while (RawTok.isNot(tok::eof)) {
36 #if 0
37 if (Tok.is(tok::raw_identifier)) {
38 // Look up the identifier info for the token. This should use
39 // IdentifierTable directly instead of PP.
40 PP.LookUpIdentifierInfo(Tok);
41 }
42 #endif
43
44 AddToken(RawTok, TokenList.end());
45 RawLex.LexFromRawLexer(RawTok);
46 }
47 }
48
~TokenRewriter()49 TokenRewriter::~TokenRewriter() {
50 }
51
52
53 /// RemapIterator - Convert from token_iterator (a const iterator) to
54 /// TokenRefTy (a non-const iterator).
RemapIterator(token_iterator I)55 TokenRewriter::TokenRefTy TokenRewriter::RemapIterator(token_iterator I) {
56 if (I == token_end()) return TokenList.end();
57
58 // FIXME: This is horrible, we should use our own list or something to avoid
59 // this.
60 std::map<SourceLocation, TokenRefTy>::iterator MapIt =
61 TokenAtLoc.find(I->getLocation());
62 assert(MapIt != TokenAtLoc.end() && "iterator not in rewriter?");
63 return MapIt->second;
64 }
65
66
67 /// AddToken - Add the specified token into the Rewriter before the other
68 /// position.
69 TokenRewriter::TokenRefTy
AddToken(const Token & T,TokenRefTy Where)70 TokenRewriter::AddToken(const Token &T, TokenRefTy Where) {
71 Where = TokenList.insert(Where, T);
72
73 bool InsertSuccess = TokenAtLoc.insert(std::make_pair(T.getLocation(),
74 Where)).second;
75 assert(InsertSuccess && "Token location already in rewriter!");
76 (void)InsertSuccess;
77 return Where;
78 }
79
80
81 TokenRewriter::token_iterator
AddTokenBefore(token_iterator I,const char * Val)82 TokenRewriter::AddTokenBefore(token_iterator I, const char *Val) {
83 unsigned Len = strlen(Val);
84
85 // Plop the string into the scratch buffer, then create a token for this
86 // string.
87 Token Tok;
88 Tok.startToken();
89 const char *Spelling;
90 Tok.setLocation(ScratchBuf->getToken(Val, Len, Spelling));
91 Tok.setLength(Len);
92
93 // TODO: Form a whole lexer around this and relex the token! For now, just
94 // set kind to tok::unknown.
95 Tok.setKind(tok::unknown);
96
97 return AddToken(Tok, RemapIterator(I));
98 }
99
100