src/llvm/include/llvm/MC/MCParser/MCAsmLexer.h

   1 //===-- llvm/MC/MCAsmLexer.h - Abstract Asm Lexer Interface -----*- 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 #ifndef LLVM_MC_MCPARSER_MCASMLEXER_H
  11 #define LLVM_MC_MCPARSER_MCASMLEXER_H
  12
  13 #include "llvm/ADT/APInt.h"
  14 #include "llvm/ADT/StringRef.h"
  15 #include "llvm/Support/Compiler.h"
  16 #include "llvm/Support/DataTypes.h"
  17 #include "llvm/Support/SMLoc.h"
  18
  19 namespace llvm {
  20
  21 /// AsmToken - Target independent representation for an assembler token.
  22 class AsmToken {
  23 public:
  24   enum TokenKind {
  25     // Markers
  26     Eof, Error,
  27
  28     // String values.
  29     Identifier,
  30     String,
  31
  32     // Integer values.
  33     Integer,
  34     BigNum, // larger than 64 bits
  35
  36     // Real values.
  37     Real,
  38
  39     // No-value.
  40     EndOfStatement,
  41     Colon,
  42     Space,
  43     Plus, Minus, Tilde,
  44     Slash,    // '/'
  45     BackSlash, // '\'
  46     LParen, RParen, LBrac, RBrac, LCurly, RCurly,
  47     Star, Dot, Comma, Dollar, Equal, EqualEqual,
  48
  49     Pipe, PipePipe, Caret,
  50     Amp, AmpAmp, Exclaim, ExclaimEqual, Percent, Hash,
  51     Less, LessEqual, LessLess, LessGreater,
  52     Greater, GreaterEqual, GreaterGreater, At
  53   };
  54
  55 private:
  56   TokenKind Kind;
  57
  58   /// A reference to the entire token contents; this is always a pointer into
  59   /// a memory buffer owned by the source manager.
  60   StringRef Str;
  61
  62   APInt IntVal;
  63
  64 public:
  65   AsmToken() {}
  66   AsmToken(TokenKind _Kind, StringRef _Str, APInt _IntVal)
  67     : Kind(_Kind), Str(_Str), IntVal(_IntVal) {}
  68   AsmToken(TokenKind _Kind, StringRef _Str, int64_t _IntVal = 0)
  69     : Kind(_Kind), Str(_Str), IntVal(64, _IntVal, true) {}
  70
  71   TokenKind getKind() const { return Kind; }
  72   bool is(TokenKind K) const { return Kind == K; }
  73   bool isNot(TokenKind K) const { return Kind != K; }
  74
  75   SMLoc getLoc() const;
  76   SMLoc getEndLoc() const;
  77
  78   /// getStringContents - Get the contents of a string token (without quotes).
  79   StringRef getStringContents() const {
  80     assert(Kind == String && "This token isn't a string!");
  81     return Str.slice(1, Str.size() - 1);
  82   }
  83
  84   /// getIdentifier - Get the identifier string for the current token, which
  85   /// should be an identifier or a string. This gets the portion of the string
  86   /// which should be used as the identifier, e.g., it does not include the
  87   /// quotes on strings.
  88   StringRef getIdentifier() const {
  89     if (Kind == Identifier)
  90       return getString();
  91     return getStringContents();
  92   }
  93
  94   /// getString - Get the string for the current token, this includes all
  95   /// characters (for example, the quotes on strings) in the token.
  96   ///
  97   /// The returned StringRef points into the source manager's memory buffer, and
  98   /// is safe to store across calls to Lex().
  99   StringRef getString() const { return Str; }
 100
 101   // FIXME: Don't compute this in advance, it makes every token larger, and is
 102   // also not generally what we want (it is nicer for recovery etc. to lex 123br
 103   // as a single token, then diagnose as an invalid number).
 104   int64_t getIntVal() const {
 105     assert(Kind == Integer && "This token isn't an integer!");
 106     return IntVal.getZExtValue();
 107   }
 108
 109   APInt getAPIntVal() const {
 110     assert((Kind == Integer || Kind == BigNum) &&
 111            "This token isn't an integer!");
 112     return IntVal;
 113   }
 114 };
 115
 116 /// MCAsmLexer - Generic assembler lexer interface, for use by target specific
 117 /// assembly lexers.
 118 class MCAsmLexer {
 119   /// The current token, stored in the base class for faster access.
 120   AsmToken CurTok;
 121
 122   /// The location and description of the current error
 123   SMLoc ErrLoc;
 124   std::string Err;
 125
 126   MCAsmLexer(const MCAsmLexer &) LLVM_DELETED_FUNCTION;
 127   void operator=(const MCAsmLexer &) LLVM_DELETED_FUNCTION;
 128 protected: // Can only create subclasses.
 129   const char *TokStart;
 130   bool SkipSpace;
 131   bool AllowAtInIdentifier;
 132
 133   MCAsmLexer();
 134
 135   virtual AsmToken LexToken() = 0;
 136
 137   void SetError(const SMLoc &errLoc, const std::string &err) {
 138     ErrLoc = errLoc;
 139     Err = err;
 140   }
 141
 142 public:
 143   virtual ~MCAsmLexer();
 144
 145   /// Lex - Consume the next token from the input stream and return it.
 146   ///
 147   /// The lexer will continuosly return the end-of-file token once the end of
 148   /// the main input file has been reached.
 149   const AsmToken &Lex() {
 150     return CurTok = LexToken();
 151   }
 152
 153   virtual StringRef LexUntilEndOfStatement() = 0;
 154
 155   /// getLoc - Get the current source location.
 156   SMLoc getLoc() const;
 157
 158   /// getTok - Get the current (last) lexed token.
 159   const AsmToken &getTok() {
 160     return CurTok;
 161   }
 162
 163   /// peekTok - Look ahead at the next token to be lexed.
 164   virtual const AsmToken peekTok(bool ShouldSkipSpace = true) = 0;
 165
 166   /// getErrLoc - Get the current error location
 167   const SMLoc &getErrLoc() {
 168     return ErrLoc;
 169   }
 170
 171   /// getErr - Get the current error string
 172   const std::string &getErr() {
 173     return Err;
 174   }
 175
 176   /// getKind - Get the kind of current token.
 177   AsmToken::TokenKind getKind() const { return CurTok.getKind(); }
 178
 179   /// is - Check if the current token has kind \p K.
 180   bool is(AsmToken::TokenKind K) const { return CurTok.is(K); }
 181
 182   /// isNot - Check if the current token has kind \p K.
 183   bool isNot(AsmToken::TokenKind K) const { return CurTok.isNot(K); }
 184
 185   /// setSkipSpace - Set whether spaces should be ignored by the lexer
 186   void setSkipSpace(bool val) { SkipSpace = val; }
 187
 188   bool getAllowAtInIdentifier() { return AllowAtInIdentifier; }
 189   void setAllowAtInIdentifier(bool v) { AllowAtInIdentifier = v; }
 190 };
 191
 192 } // End llvm namespace
 193
 194 #endif