1 //===- PTHLexer.h - Lexer based on Pre-tokenized input ----------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the PTHLexer interface.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CLANG_LEX_PTHLEXER_H
15 #define LLVM_CLANG_LEX_PTHLEXER_H
17 #include "clang/Basic/SourceLocation.h"
18 #include "clang/Basic/TokenKinds.h"
19 #include "clang/Lex/PreprocessorLexer.h"
20 #include "clang/Lex/Token.h"
27 class PTHLexer : public PreprocessorLexer {
28 SourceLocation FileStartLoc;
30 /// TokBuf - Buffer from PTH file containing raw token data.
31 const unsigned char* TokBuf;
33 /// CurPtr - Pointer into current offset of the token buffer where
34 /// the next token will be read.
35 const unsigned char* CurPtr;
37 /// LastHashTokPtr - Pointer into TokBuf of the last processed '#'
38 /// token that appears at the start of a line.
39 const unsigned char* LastHashTokPtr = nullptr;
41 /// PPCond - Pointer to a side table in the PTH file that provides a
42 /// a concise summary of the preprocessor conditional block structure.
43 /// This is used to perform quick skipping of conditional blocks.
44 const unsigned char* PPCond;
46 /// CurPPCondPtr - Pointer inside PPCond that refers to the next entry
47 /// to process when doing quick skipping of preprocessor blocks.
48 const unsigned char* CurPPCondPtr;
50 /// ReadToken - Used by PTHLexer to read tokens TokBuf.
51 void ReadToken(Token &T);
53 bool LexEndOfFile(Token &Result);
55 /// PTHMgr - The PTHManager object that created this PTHLexer.
61 friend class PTHManager;
63 /// Create a PTHLexer for the specified token stream.
64 PTHLexer(Preprocessor &pp, FileID FID, const unsigned char *D,
65 const unsigned char* ppcond, PTHManager &PM);
68 PTHLexer(const PTHLexer &) = delete;
69 PTHLexer &operator=(const PTHLexer &) = delete;
70 ~PTHLexer() override = default;
72 /// Lex - Return the next token.
75 void getEOF(Token &Tok);
77 /// DiscardToEndOfLine - Read the rest of the current preprocessor line as an
78 /// uninterpreted string. This switches the lexer out of directive mode.
79 void DiscardToEndOfLine();
81 /// isNextPPTokenLParen - Return 1 if the next unexpanded token will return a
82 /// tok::l_paren token, 0 if it is something else and 2 if there are no more
83 /// tokens controlled by this lexer.
84 unsigned isNextPPTokenLParen() {
85 // isNextPPTokenLParen is not on the hot path, and all we care about is
86 // whether or not we are at a token with kind tok::eof or tok::l_paren.
87 // Just read the first byte from the current token pointer to determine
89 tok::TokenKind x = (tok::TokenKind)*CurPtr;
90 return x == tok::eof ? 2 : x == tok::l_paren;
93 /// IndirectLex - An indirect call to 'Lex' that can be invoked via
94 /// the PreprocessorLexer interface.
95 void IndirectLex(Token &Result) override { Lex(Result); }
97 /// getSourceLocation - Return a source location for the token in
99 SourceLocation getSourceLocation() override;
101 /// SkipBlock - Used by Preprocessor to skip the current conditional block.
107 #endif // LLVM_CLANG_LEX_PTHLEXER_H