v8/src/unicode-cache.h
Marja Hölttä 2b6780dc17 [scanner] Don't use UnicodeCache for IsLineTerminator.
For such a simple predicate, calling a(n inline) function that checks against
the values is faster (*) than maintaining the cache.

(*) When scanning a file that contains only comments, we're basically calling
IsLineTerminator in a loop. Parsing such files is now 7-18% faster in local
experiments.

BUG=v8:6092

Change-Id: I6a8f2aba9669a76152292f4e6c7853638d15aae3
Reviewed-on: https://chromium-review.googlesource.com/645633
Commit-Queue: Marja Hölttä <marja@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47810}
2017-09-05 07:04:06 +00:00

47 lines
1.4 KiB
C++

// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_UNICODE_CACHE_H_
#define V8_UNICODE_CACHE_H_
#include "src/base/macros.h"
#include "src/char-predicates.h"
#include "src/unicode.h"
#include "src/unicode-decoder.h"
namespace v8 {
namespace internal {
// Caching predicates used by scanners.
class UnicodeCache {
public:
UnicodeCache() {}
typedef unibrow::Utf8Decoder<512> Utf8Decoder;
StaticResource<Utf8Decoder>* utf8_decoder() { return &utf8_decoder_; }
inline bool IsIdentifierStart(unibrow::uchar c);
inline bool IsIdentifierPart(unibrow::uchar c);
inline bool IsLineTerminator(unibrow::uchar c);
inline bool IsLineTerminatorSequence(unibrow::uchar c, unibrow::uchar next);
inline bool IsWhiteSpace(unibrow::uchar c);
inline bool IsWhiteSpaceOrLineTerminator(unibrow::uchar c);
private:
unibrow::Predicate<IdentifierStart, 128> kIsIdentifierStart;
unibrow::Predicate<IdentifierPart, 128> kIsIdentifierPart;
unibrow::Predicate<WhiteSpace, 128> kIsWhiteSpace;
unibrow::Predicate<WhiteSpaceOrLineTerminator, 128>
kIsWhiteSpaceOrLineTerminator;
StaticResource<Utf8Decoder> utf8_decoder_;
DISALLOW_COPY_AND_ASSIGN(UnicodeCache);
};
} // namespace internal
} // namespace v8
#endif // V8_UNICODE_CACHE_H_