Move part of scanner.* into scanner-base.* for reuse in preparser scanner.

src/scanner-base.h

+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Features shared by parsing and pre-parsing scanners.
+
+#ifndef V8_SCANNER_BASE_H_
+#define V8_SCANNER_BASE_H_
+
+#include "token.h"
+#include "unicode.h"
+
+namespace v8 {
+namespace internal {
+
+class KeywordMatcher {
+//  Incrementally recognize keywords.
+//
+//  Recognized keywords:
+//      break case catch const* continue debugger* default delete do else
+//      finally false for function if in instanceof native* new null
+//      return switch this throw true try typeof var void while with
+//
+//  *: Actually "future reserved keywords". These are the only ones we
+//     recognized, the remaining are allowed as identifiers.
+ public:
+  KeywordMatcher()
+      : state_(INITIAL),
+        token_(Token::IDENTIFIER),
+        keyword_(NULL),
+        counter_(0),
+        keyword_token_(Token::ILLEGAL) {}
+
+  Token::Value token() { return token_; }
+
+  inline void AddChar(unibrow::uchar input) {
+    if (state_ != UNMATCHABLE) {
+      Step(input);
+    }
+  }
+
+  void Fail() {
+    token_ = Token::IDENTIFIER;
+    state_ = UNMATCHABLE;
+  }
+
+ private:
+  enum State {
+    UNMATCHABLE,
+    INITIAL,
+    KEYWORD_PREFIX,
+    KEYWORD_MATCHED,
+    C,
+    CA,
+    CO,
+    CON,
+    D,
+    DE,
+    F,
+    I,
+    IN,
+    N,
+    T,
+    TH,
+    TR,
+    V,
+    W
+  };
+
+  struct FirstState {
+    const char* keyword;
+    State state;
+    Token::Value token;
+  };
+
+  // Range of possible first characters of a keyword.
+  static const unsigned int kFirstCharRangeMin = 'b';
+  static const unsigned int kFirstCharRangeMax = 'w';
+  static const unsigned int kFirstCharRangeLength =
+      kFirstCharRangeMax - kFirstCharRangeMin + 1;
+  // State map for first keyword character range.
+  static FirstState first_states_[kFirstCharRangeLength];
+
+  // If input equals keyword's character at position, continue matching keyword
+  // from that position.
+  inline bool MatchKeywordStart(unibrow::uchar input,
+                                const char* keyword,
+                                int position,
+                                Token::Value token_if_match) {
+    if (input == static_cast<unibrow::uchar>(keyword[position])) {
+      state_ = KEYWORD_PREFIX;
+      this->keyword_ = keyword;
+      this->counter_ = position + 1;
+      this->keyword_token_ = token_if_match;
+      return true;
+    }
+    return false;
+  }
+
+  // If input equals match character, transition to new state and return true.
+  inline bool MatchState(unibrow::uchar input, char match, State new_state) {
+    if (input == static_cast<unibrow::uchar>(match)) {
+      state_ = new_state;
+      return true;
+    }
+    return false;
+  }
+
+  inline bool MatchKeyword(unibrow::uchar input,
+                           char match,
+                           State new_state,
+                           Token::Value keyword_token) {
+    if (input != static_cast<unibrow::uchar>(match)) {
+      return false;
+    }
+    state_ = new_state;
+    token_ = keyword_token;
+    return true;
+  }
+
+  void Step(unibrow::uchar input);
+
+  // Current state.
+  State state_;
+  // Token for currently added characters.
+  Token::Value token_;
+
+  // Matching a specific keyword string (there is only one possible valid
+  // keyword with the current prefix).
+  const char* keyword_;
+  int counter_;
+  Token::Value keyword_token_;
+};
+
+
+

[Mads Ager (chromium), 2010/11/05 13:29:27]

Excessive spacing.

+
+
+
+} }  // namespace v8::internal
+
+#endif  // V8_SCANNER_BASE_H_