github.com/johnnyeven/libtools@v0.0.0-20191126065708-61829c1adf46/third_party/mlir/lib/Parser/Lexer.h (about)

     1  //===- Lexer.h - MLIR Lexer Interface ---------------------------*- C++ -*-===//
     2  //
     3  // Copyright 2019 The MLIR Authors.
     4  //
     5  // Licensed under the Apache License, Version 2.0 (the "License");
     6  // you may not use this file except in compliance with the License.
     7  // You may obtain a copy of the License at
     8  //
     9  //   http://www.apache.org/licenses/LICENSE-2.0
    10  //
    11  // Unless required by applicable law or agreed to in writing, software
    12  // distributed under the License is distributed on an "AS IS" BASIS,
    13  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14  // See the License for the specific language governing permissions and
    15  // limitations under the License.
    16  // =============================================================================
    17  //
    18  // This file declares the MLIR Lexer class.
    19  //
    20  //===----------------------------------------------------------------------===//
    21  
    22  #ifndef MLIR_LIB_PARSER_LEXER_H
    23  #define MLIR_LIB_PARSER_LEXER_H
    24  
    25  #include "Token.h"
    26  #include "mlir/Parser.h"
    27  
    28  namespace mlir {
    29  class Location;
    30  
    31  /// This class breaks up the current file into a token stream.
    32  class Lexer {
    33  public:
    34    explicit Lexer(const llvm::SourceMgr &sourceMgr, MLIRContext *context);
    35  
    36    const llvm::SourceMgr &getSourceMgr() { return sourceMgr; }
    37  
    38    Token lexToken();
    39  
    40    /// Encode the specified source location information into a Location object
    41    /// for attachment to the IR or error reporting.
    42    Location getEncodedSourceLocation(llvm::SMLoc loc);
    43  
    44    /// Change the position of the lexer cursor.  The next token we lex will start
    45    /// at the designated point in the input.
    46    void resetPointer(const char *newPointer) { curPtr = newPointer; }
    47  
    48  private:
    49    // Helpers.
    50    Token formToken(Token::Kind kind, const char *tokStart) {
    51      return Token(kind, StringRef(tokStart, curPtr - tokStart));
    52    }
    53  
    54    Token emitError(const char *loc, const Twine &message);
    55  
    56    // Lexer implementation methods.
    57    Token lexAtIdentifier(const char *tokStart);
    58    Token lexBareIdentifierOrKeyword(const char *tokStart);
    59    Token lexComment();
    60    Token lexEllipsis(const char *tokStart);
    61    Token lexNumber(const char *tokStart);
    62    Token lexPrefixedIdentifier(const char *tokStart);
    63    Token lexString(const char *tokStart);
    64  
    65    const llvm::SourceMgr &sourceMgr;
    66    MLIRContext *context;
    67  
    68    StringRef curBuffer;
    69    const char *curPtr;
    70  
    71    Lexer(const Lexer &) = delete;
    72    void operator=(const Lexer &) = delete;
    73  };
    74  
    75  } // end namespace mlir
    76  
    77  #endif // MLIR_LIB_PARSER_LEXER_H