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/*
* Copyright (C) 2021 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. AND ITS 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 APPLE INC. OR ITS 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 "Identifier.h"
#include "JSONAtomStringCache.h"
#include "SmallStrings.h"
#include "VM.h"
namespace JSC {
template<typename CharacterType>
ALWAYS_INLINE Ref<AtomStringImpl> JSONAtomStringCache::makeIdentifier(std::span<const CharacterType> characters)
{
if (characters.empty())
return *emptyAtom().impl();
auto firstCharacter = characters.front();
if (characters.size() == 1) {
if (firstCharacter <= maxSingleCharacterString)
return vm().smallStrings.singleCharacterStringRep(firstCharacter);
} else if (characters.size() > maxStringLengthForCache) [[unlikely]]
return AtomStringImpl::add(characters).releaseNonNull();
auto lastCharacter = characters.back();
auto& slot = cacheSlot(firstCharacter, lastCharacter, characters.size());
if (slot.m_length != characters.size() || !equal(slot.m_buffer, characters)) [[unlikely]] {
auto result = AtomStringImpl::add(characters);
slot.m_impl = result;
slot.m_length = characters.size();
WTF::copyElements(std::span<char16_t> { slot.m_buffer }, characters);
return result.releaseNonNull();
}
return *slot.m_impl;
}
template<typename CharacterType>
ALWAYS_INLINE AtomStringImpl* JSONAtomStringCache::existingIdentifier(std::span<const CharacterType> characters)
{
if (characters.empty())
return emptyAtom().impl();
auto firstCharacter = characters.front();
if (characters.size() == 1) {
if (firstCharacter <= maxSingleCharacterString)
return vm().smallStrings.existingSingleCharacterStringRep(firstCharacter);
} else if (characters.size() > maxStringLengthForCache) [[unlikely]]
return nullptr;
auto lastCharacter = characters.back();
auto& slot = cacheSlot(firstCharacter, lastCharacter, characters.size());
if (slot.m_length != characters.size() || !equal(slot.m_buffer, characters)) [[unlikely]]
return nullptr;
return slot.m_impl.get();
}
ALWAYS_INLINE VM& JSONAtomStringCache::vm() const
{
return *std::bit_cast<VM*>(std::bit_cast<uintptr_t>(this) - OBJECT_OFFSETOF(VM, jsonAtomStringCache));
}
} // namespace JSC
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