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/*
* Copyright (C) 2009 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.
*/
#pragma once
#include "PureNaN.h"
#include <array>
#include <wtf/GregorianDateTime.h>
#include <wtf/HashFunctions.h>
#include <wtf/RefCounted.h>
namespace JSC {
class DateInstanceData : public RefCounted<DateInstanceData> {
public:
static Ref<DateInstanceData> create() { return adoptRef(*new DateInstanceData); }
static constexpr ptrdiff_t offsetOfGregorianDateTimeCachedForMS() { return OBJECT_OFFSETOF(DateInstanceData, m_gregorianDateTimeCachedForMS); }
static constexpr ptrdiff_t offsetOfCachedGregorianDateTime() { return OBJECT_OFFSETOF(DateInstanceData, m_cachedGregorianDateTime); }
static constexpr ptrdiff_t offsetOfGregorianDateTimeUTCCachedForMS() { return OBJECT_OFFSETOF(DateInstanceData, m_gregorianDateTimeUTCCachedForMS); }
static constexpr ptrdiff_t offsetOfCachedGregorianDateTimeUTC() { return OBJECT_OFFSETOF(DateInstanceData, m_cachedGregorianDateTimeUTC); }
double m_gregorianDateTimeCachedForMS { PNaN };
GregorianDateTime m_cachedGregorianDateTime;
double m_gregorianDateTimeUTCCachedForMS { PNaN };
GregorianDateTime m_cachedGregorianDateTimeUTC;
private:
DateInstanceData() = default;
};
class DateInstanceCache {
public:
DateInstanceCache()
{
reset();
}
void reset()
{
for (size_t i = 0; i < cacheSize; ++i)
m_cache[i].key = PNaN;
}
DateInstanceData* add(double d)
{
CacheEntry& entry = lookup(d);
if (d == entry.key)
return entry.value.get();
entry.key = d;
entry.value = DateInstanceData::create();
return entry.value.get();
}
private:
static const size_t cacheSize = 16;
struct CacheEntry {
double key;
RefPtr<DateInstanceData> value;
};
CacheEntry& lookup(double d) { return m_cache[WTF::FloatHash<double>::hash(d) & (cacheSize - 1)]; }
std::array<CacheEntry, cacheSize> m_cache;
};
} // namespace JSC
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