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Diffstat (limited to 'src/3rdparty/webkit/JavaScriptCore/runtime/SmallStrings.cpp')
-rw-r--r-- | src/3rdparty/webkit/JavaScriptCore/runtime/SmallStrings.cpp | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/src/3rdparty/webkit/JavaScriptCore/runtime/SmallStrings.cpp b/src/3rdparty/webkit/JavaScriptCore/runtime/SmallStrings.cpp new file mode 100644 index 0000000..06811b9 --- /dev/null +++ b/src/3rdparty/webkit/JavaScriptCore/runtime/SmallStrings.cpp @@ -0,0 +1,112 @@ +/* + * Copyright (C) 2008 Apple Inc. All Rights Reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * + * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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. + */ + +#include "config.h" +#include "SmallStrings.h" + +#include "JSGlobalObject.h" +#include "JSString.h" + +namespace JSC { + +class SmallStringsStorage { +public: + SmallStringsStorage(); + ~SmallStringsStorage(); + + UString::Rep* rep(unsigned char character) { return &reps[character]; } + +private: + UChar characters[0x100]; + UString::Rep* reps; +}; + +SmallStringsStorage::SmallStringsStorage() + : reps(static_cast<UString::Rep*>(fastZeroedMalloc(sizeof(UString::Rep) * 0x100))) +{ + for (unsigned i = 0; i < 0x100; ++i) { + characters[i] = i; + reps[i].offset = i; + reps[i].len = 1; + reps[i].rc = 1; + reps[i].baseString = &reps[0]; + } + reps[0].rc = 0x101; + reps[0].buf = characters; + + // make sure UString doesn't try to reuse the buffer by pretending we have one more character in it + reps[0].usedCapacity = 0x101; + reps[0].capacity = 0x101; +} + +SmallStringsStorage::~SmallStringsStorage() +{ + fastFree(reps); +} + +SmallStrings::SmallStrings() + : m_emptyString(0) + , m_storage(0) +{ + for (unsigned i = 0; i < 0x100; ++i) + m_singleCharacterStrings[i] = 0; +} + +SmallStrings::~SmallStrings() +{ +} + +void SmallStrings::mark() +{ + if (m_emptyString && !m_emptyString->marked()) + m_emptyString->mark(); + for (unsigned i = 0; i < 0x100; ++i) { + if (m_singleCharacterStrings[i] && !m_singleCharacterStrings[i]->marked()) + m_singleCharacterStrings[i]->mark(); + } +} + +void SmallStrings::createEmptyString(JSGlobalData* globalData) +{ + ASSERT(!m_emptyString); + m_emptyString = new (globalData) JSString(globalData, "", JSString::HasOtherOwner); +} + +void SmallStrings::createSingleCharacterString(JSGlobalData* globalData, unsigned char character) +{ + if (!m_storage) + m_storage.set(new SmallStringsStorage); + ASSERT(!m_singleCharacterStrings[character]); + m_singleCharacterStrings[character] = new (globalData) JSString(globalData, m_storage->rep(character), JSString::HasOtherOwner); +} + +UString::Rep* SmallStrings::singleCharacterStringRep(unsigned char character) +{ + if (!m_storage) + m_storage.set(new SmallStringsStorage); + return m_storage->rep(character); +} + +} |