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Diffstat (limited to 'deps/v8/src/scanner-base.cc')
| -rw-r--r-- | deps/v8/src/scanner-base.cc | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/deps/v8/src/scanner-base.cc b/deps/v8/src/scanner-base.cc new file mode 100644 index 000000000..6e9d40e0d --- /dev/null +++ b/deps/v8/src/scanner-base.cc @@ -0,0 +1,167 @@ +// 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. + +#include "scanner-base.h" + +namespace v8 { +namespace internal { + +// ---------------------------------------------------------------------------- +// Keyword Matcher + +KeywordMatcher::FirstState KeywordMatcher::first_states_[] = { + { "break", KEYWORD_PREFIX, Token::BREAK }, + { NULL, C, Token::ILLEGAL }, + { NULL, D, Token::ILLEGAL }, + { "else", KEYWORD_PREFIX, Token::ELSE }, + { NULL, F, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, I, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, N, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { "return", KEYWORD_PREFIX, Token::RETURN }, + { "switch", KEYWORD_PREFIX, Token::SWITCH }, + { NULL, T, Token::ILLEGAL }, + { NULL, UNMATCHABLE, Token::ILLEGAL }, + { NULL, V, Token::ILLEGAL }, + { NULL, W, Token::ILLEGAL } +}; + + +void KeywordMatcher::Step(unibrow::uchar input) { + switch (state_) { + case INITIAL: { + // matching the first character is the only state with significant fanout. + // Match only lower-case letters in range 'b'..'w'. + unsigned int offset = input - kFirstCharRangeMin; + if (offset < kFirstCharRangeLength) { + state_ = first_states_[offset].state; + if (state_ == KEYWORD_PREFIX) { + keyword_ = first_states_[offset].keyword; + counter_ = 1; + keyword_token_ = first_states_[offset].token; + } + return; + } + break; + } + case KEYWORD_PREFIX: + if (static_cast<unibrow::uchar>(keyword_[counter_]) == input) { + counter_++; + if (keyword_[counter_] == '\0') { + state_ = KEYWORD_MATCHED; + token_ = keyword_token_; + } + return; + } + break; + case KEYWORD_MATCHED: + token_ = Token::IDENTIFIER; + break; + case C: + if (MatchState(input, 'a', CA)) return; + if (MatchState(input, 'o', CO)) return; + break; + case CA: + if (MatchKeywordStart(input, "case", 2, Token::CASE)) return; + if (MatchKeywordStart(input, "catch", 2, Token::CATCH)) return; + break; + case CO: + if (MatchState(input, 'n', CON)) return; + break; + case CON: + if (MatchKeywordStart(input, "const", 3, Token::CONST)) return; + if (MatchKeywordStart(input, "continue", 3, Token::CONTINUE)) return; + break; + case D: + if (MatchState(input, 'e', DE)) return; + if (MatchKeyword(input, 'o', KEYWORD_MATCHED, Token::DO)) return; + break; + case DE: + if (MatchKeywordStart(input, "debugger", 2, Token::DEBUGGER)) return; + if (MatchKeywordStart(input, "default", 2, Token::DEFAULT)) return; + if (MatchKeywordStart(input, "delete", 2, Token::DELETE)) return; + break; + case F: + if (MatchKeywordStart(input, "false", 1, Token::FALSE_LITERAL)) return; + if (MatchKeywordStart(input, "finally", 1, Token::FINALLY)) return; + if (MatchKeywordStart(input, "for", 1, Token::FOR)) return; + if (MatchKeywordStart(input, "function", 1, Token::FUNCTION)) return; + break; + case I: + if (MatchKeyword(input, 'f', KEYWORD_MATCHED, Token::IF)) return; + if (MatchKeyword(input, 'n', IN, Token::IN)) return; + break; + case IN: + token_ = Token::IDENTIFIER; + if (MatchKeywordStart(input, "instanceof", 2, Token::INSTANCEOF)) { + return; + } + break; + case N: + if (MatchKeywordStart(input, "native", 1, Token::NATIVE)) return; + if (MatchKeywordStart(input, "new", 1, Token::NEW)) return; + if (MatchKeywordStart(input, "null", 1, Token::NULL_LITERAL)) return; + break; + case T: + if (MatchState(input, 'h', TH)) return; + if (MatchState(input, 'r', TR)) return; + if (MatchKeywordStart(input, "typeof", 1, Token::TYPEOF)) return; + break; + case TH: + if (MatchKeywordStart(input, "this", 2, Token::THIS)) return; + if (MatchKeywordStart(input, "throw", 2, Token::THROW)) return; + break; + case TR: + if (MatchKeywordStart(input, "true", 2, Token::TRUE_LITERAL)) return; + if (MatchKeyword(input, 'y', KEYWORD_MATCHED, Token::TRY)) return; + break; + case V: + if (MatchKeywordStart(input, "var", 1, Token::VAR)) return; + if (MatchKeywordStart(input, "void", 1, Token::VOID)) return; + break; + case W: + if (MatchKeywordStart(input, "while", 1, Token::WHILE)) return; + if (MatchKeywordStart(input, "with", 1, Token::WITH)) return; + break; + case UNMATCHABLE: + break; + } + // On fallthrough, it's a failure. + state_ = UNMATCHABLE; +} + +} } // namespace v8::internal |