mlir/lib/AsmParser/Lexer.h

   1 //===- Lexer.h - MLIR Lexer Interface ---------------------------*- C++ -*-===//
   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 file declares the MLIR Lexer class.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef MLIR_LIB_ASMPARSER_LEXER_H
  14 #define MLIR_LIB_ASMPARSER_LEXER_H
  15
  16 #include "Token.h"
  17 #include "mlir/AsmParser/AsmParser.h"
  18
  19 namespace mlir {
  20 class Location;
  21
  22 /// This class breaks up the current file into a token stream.
  23 class Lexer {
  24 public:
  25   explicit Lexer(const llvm::SourceMgr &sourceMgr, MLIRContext *context,
  26                  AsmParserCodeCompleteContext *codeCompleteContext);
  27
  28   const llvm::SourceMgr &getSourceMgr() { return sourceMgr; }
  29
  30   Token lexToken();
  31
  32   /// Encode the specified source location information into a Location object
  33   /// for attachment to the IR or error reporting.
  34   Location getEncodedSourceLocation(SMLoc loc);
  35
  36   /// Change the position of the lexer cursor.  The next token we lex will start
  37   /// at the designated point in the input.
  38   void resetPointer(const char *newPointer) { curPtr = newPointer; }
  39
  40   /// Returns the start of the buffer.
  41   const char *getBufferBegin() { return curBuffer.data(); }
  42
  43   /// Return the code completion location of the lexer, or nullptr if there is
  44   /// none.
  45   const char *getCodeCompleteLoc() const { return codeCompleteLoc; }
  46
  47 private:
  48   // Helpers.
  49   Token formToken(Token::Kind kind, const char *tokStart) {
  50     return Token(kind, StringRef(tokStart, curPtr - tokStart));
  51   }
  52
  53   Token emitError(const char *loc, const Twine &message);
  54
  55   // Lexer implementation methods.
  56   Token lexAtIdentifier(const char *tokStart);
  57   Token lexBareIdentifierOrKeyword(const char *tokStart);
  58   Token lexEllipsis(const char *tokStart);
  59   Token lexNumber(const char *tokStart);
  60   Token lexPrefixedIdentifier(const char *tokStart);
  61   Token lexString(const char *tokStart);
  62
  63   /// Skip a comment line, starting with a '//'.
  64   void skipComment();
  65
  66   const llvm::SourceMgr &sourceMgr;
  67   MLIRContext *context;
  68
  69   StringRef curBuffer;
  70   const char *curPtr;
  71
  72   /// An optional code completion point within the input file, used to indicate
  73   /// the position of a code completion token.
  74   const char *codeCompleteLoc;
  75
  76   Lexer(const Lexer &) = delete;
  77   void operator=(const Lexer &) = delete;
  78 };
  79
  80 } // namespace mlir
  81
  82 #endif // MLIR_LIB_ASMPARSER_LEXER_H