lib/TableGen/TGLexer.h

   1 //===- TGLexer.h - Lexer for TableGen Files ---------------------*- C++ -*-===//
   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 class represents the Lexer for tablegen files.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_LIB_TABLEGEN_TGLEXER_H
  15 #define LLVM_LIB_TABLEGEN_TGLEXER_H
  16
  17 #include "llvm/ADT/StringRef.h"
  18 #include "llvm/Support/DataTypes.h"
  19 #include "llvm/Support/SMLoc.h"
  20 #include <cassert>
  21 #include <map>
  22 #include <string>
  23
  24 namespace llvm {
  25 class SourceMgr;
  26 class SMLoc;
  27 class Twine;
  28
  29 namespace tgtok {
  30   enum TokKind {
  31     // Markers
  32     Eof, Error,
  33
  34     // Tokens with no info.
  35     minus, plus,        // - +
  36     l_square, r_square, // [ ]
  37     l_brace, r_brace,   // { }
  38     l_paren, r_paren,   // ( )
  39     less, greater,      // < >
  40     colon, semi,        // : ;
  41     comma, period,      // , .
  42     equal, question,    // = ?
  43     paste,              // #
  44
  45     // Keywords.
  46     Bit, Bits, Class, Code, Dag, Def, Foreach, Defm, Field, In, Int, Let, List,
  47     MultiClass, String, Defset,
  48
  49     // !keywords.
  50     XConcat, XADD, XAND, XOR, XSRA, XSRL, XSHL, XListConcat, XStrConcat, XCast,
  51     XSubst, XForEach, XFoldl, XHead, XTail, XSize, XEmpty, XIf, XEq, XIsA, XDag,
  52     XNe, XLe, XLt, XGe, XGt,
  53
  54     // Integer value.
  55     IntVal,
  56
  57     // Binary constant.  Note that these are sized according to the number of
  58     // bits given.
  59     BinaryIntVal,
  60
  61     // String valued tokens.
  62     Id, StrVal, VarName, CodeFragment
  63   };
  64 }
  65
  66 /// TGLexer - TableGen Lexer class.
  67 class TGLexer {
  68   SourceMgr &SrcMgr;
  69
  70   const char *CurPtr;
  71   StringRef CurBuf;
  72
  73   // Information about the current token.
  74   const char *TokStart;
  75   tgtok::TokKind CurCode;
  76   std::string CurStrVal;  // This is valid for ID, STRVAL, VARNAME, CODEFRAGMENT
  77   int64_t CurIntVal;      // This is valid for INTVAL.
  78
  79   /// CurBuffer - This is the current buffer index we're lexing from as managed
  80   /// by the SourceMgr object.
  81   unsigned CurBuffer;
  82
  83 public:
  84   typedef std::map<std::string, SMLoc> DependenciesMapTy;
  85 private:
  86   /// Dependencies - This is the list of all included files.
  87   DependenciesMapTy Dependencies;
  88
  89 public:
  90   TGLexer(SourceMgr &SrcMgr);
  91
  92   tgtok::TokKind Lex() {
  93     return CurCode = LexToken();
  94   }
  95
  96   const DependenciesMapTy &getDependencies() const {
  97     return Dependencies;
  98   }
  99
 100   tgtok::TokKind getCode() const { return CurCode; }
 101
 102   const std::string &getCurStrVal() const {
 103     assert((CurCode == tgtok::Id || CurCode == tgtok::StrVal ||
 104             CurCode == tgtok::VarName || CurCode == tgtok::CodeFragment) &&
 105            "This token doesn't have a string value");
 106     return CurStrVal;
 107   }
 108   int64_t getCurIntVal() const {
 109     assert(CurCode == tgtok::IntVal && "This token isn't an integer");
 110     return CurIntVal;
 111   }
 112   std::pair<int64_t, unsigned> getCurBinaryIntVal() const {
 113     assert(CurCode == tgtok::BinaryIntVal &&
 114            "This token isn't a binary integer");
 115     return std::make_pair(CurIntVal, (CurPtr - TokStart)-2);
 116   }
 117
 118   SMLoc getLoc() const;
 119
 120 private:
 121   /// LexToken - Read the next token and return its code.
 122   tgtok::TokKind LexToken();
 123
 124   tgtok::TokKind ReturnError(const char *Loc, const Twine &Msg);
 125
 126   int getNextChar();
 127   int peekNextChar(int Index);
 128   void SkipBCPLComment();
 129   bool SkipCComment();
 130   tgtok::TokKind LexIdentifier();
 131   bool LexInclude();
 132   tgtok::TokKind LexString();
 133   tgtok::TokKind LexVarName();
 134   tgtok::TokKind LexNumber();
 135   tgtok::TokKind LexBracket();
 136   tgtok::TokKind LexExclaim();
 137 };
 138
 139 } // end namespace llvm
 140
 141 #endif