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/*
* Copyright (C) 2008, 2010 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 "HeapRootVisitor.h"
#include "JSGlobalObject.h"
#include "JSString.h"
#include <wtf/Noncopyable.h>
#include <wtf/PassOwnPtr.h>
#include <wtf/text/StringImpl.h>
namespace JSC {
static inline void finalize(JSString*& string)
{
if (!string || Heap::isMarked(string))
return;
string = 0;
}
class SmallStringsStorage {
WTF_MAKE_NONCOPYABLE(SmallStringsStorage); WTF_MAKE_FAST_ALLOCATED;
public:
SmallStringsStorage();
StringImpl* rep(unsigned char character)
{
return m_reps[character].get();
}
private:
static const unsigned singleCharacterStringCount = maxSingleCharacterString + 1;
RefPtr<StringImpl> m_reps[singleCharacterStringCount];
};
SmallStringsStorage::SmallStringsStorage()
{
LChar* characterBuffer = 0;
RefPtr<StringImpl> baseString = StringImpl::createUninitialized(singleCharacterStringCount, characterBuffer);
for (unsigned i = 0; i < singleCharacterStringCount; ++i) {
characterBuffer[i] = i;
m_reps[i] = StringImpl::create(baseString, i, 1);
}
}
SmallStrings::SmallStrings()
: m_emptyString(0)
#define JSC_COMMON_STRINGS_ATTRIBUTE_INITIALIZE(name) , m_##name(0)
JSC_COMMON_STRINGS_EACH_NAME(JSC_COMMON_STRINGS_ATTRIBUTE_INITIALIZE)
#undef JSC_COMMON_STRINGS_ATTRIBUTE_INITIALIZE
{
COMPILE_ASSERT(singleCharacterStringCount == sizeof(m_singleCharacterStrings) / sizeof(m_singleCharacterStrings[0]), IsNumCharactersConstInSyncWithClassUsage);
for (unsigned i = 0; i < singleCharacterStringCount; ++i)
m_singleCharacterStrings[i] = 0;
}
SmallStrings::~SmallStrings()
{
}
void SmallStrings::finalizeSmallStrings()
{
finalize(m_emptyString);
for (unsigned i = 0; i < singleCharacterStringCount; ++i)
finalize(m_singleCharacterStrings[i]);
#define JSC_COMMON_STRINGS_ATTRIBUTE_FINALIZE(name) finalize(m_##name);
JSC_COMMON_STRINGS_EACH_NAME(JSC_COMMON_STRINGS_ATTRIBUTE_FINALIZE)
#undef JSC_COMMON_STRINGS_ATTRIBUTE_FINALIZE
}
void SmallStrings::createEmptyString(JSGlobalData* globalData)
{
ASSERT(!m_emptyString);
m_emptyString = JSString::createHasOtherOwner(*globalData, StringImpl::empty());
}
void SmallStrings::createSingleCharacterString(JSGlobalData* globalData, unsigned char character)
{
if (!m_storage)
m_storage = adoptPtr(new SmallStringsStorage);
ASSERT(!m_singleCharacterStrings[character]);
m_singleCharacterStrings[character] = JSString::createHasOtherOwner(*globalData, PassRefPtr<StringImpl>(m_storage->rep(character)));
}
StringImpl* SmallStrings::singleCharacterStringRep(unsigned char character)
{
if (!m_storage)
m_storage = adoptPtr(new SmallStringsStorage);
return m_storage->rep(character);
}
void SmallStrings::initialize(JSGlobalData* globalData, JSString*& string, const char* value) const
{
string = JSString::create(*globalData, StringImpl::create(value));
}
} // namespace JSC
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