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/*
* Copyright (C) 2008-2009, 2015-2016 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 "TypeofType.h"
#include "WriteBarrier.h"
#include <wtf/Noncopyable.h>
#define JSC_COMMON_STRINGS_EACH_NAME(macro) \
macro(default) \
macro(boolean) \
macro(false) \
macro(function) \
macro(number) \
macro(null) \
macro(object) \
macro(undefined) \
macro(string) \
macro(symbol) \
macro(true)
namespace WTF {
class StringImpl;
}
namespace JSC {
class VM;
class JSString;
class SmallStringsStorage;
class SlotVisitor;
static const unsigned maxSingleCharacterString = 0xFF;
class SmallStrings {
WTF_MAKE_NONCOPYABLE(SmallStrings);
public:
SmallStrings();
~SmallStrings();
JSString* emptyString()
{
return m_emptyString;
}
JSString* singleCharacterString(unsigned char character)
{
return m_singleCharacterStrings[character];
}
JS_EXPORT_PRIVATE WTF::StringImpl& singleCharacterStringRep(unsigned char character);
JSString** singleCharacterStrings() { return &m_singleCharacterStrings[0]; }
void initializeCommonStrings(VM&);
void visitStrongReferences(SlotVisitor&);
#define JSC_COMMON_STRINGS_ACCESSOR_DEFINITION(name) \
JSString* name##String() const \
{ \
return m_##name; \
}
JSC_COMMON_STRINGS_EACH_NAME(JSC_COMMON_STRINGS_ACCESSOR_DEFINITION)
#undef JSC_COMMON_STRINGS_ACCESSOR_DEFINITION
JSString* typeString(TypeofType type) const
{
switch (type) {
case TypeofType::Undefined:
return undefinedString();
case TypeofType::Boolean:
return booleanString();
case TypeofType::Number:
return numberString();
case TypeofType::String:
return stringString();
case TypeofType::Symbol:
return symbolString();
case TypeofType::Object:
return objectString();
case TypeofType::Function:
return functionString();
}
RELEASE_ASSERT_NOT_REACHED();
return nullptr;
}
JSString* objectStringStart() const { return m_objectStringStart; }
JSString* nullObjectString() const { return m_nullObjectString; }
JSString* undefinedObjectString() const { return m_undefinedObjectString; }
bool needsToBeVisited(CollectionScope scope) const
{
if (scope == CollectionScope::Full)
return true;
return m_needsToBeVisited;
}
private:
static const unsigned singleCharacterStringCount = maxSingleCharacterString + 1;
void createEmptyString(VM*);
void createSingleCharacterString(VM*, unsigned char);
void initialize(VM*, JSString*&, const char* value);
JSString* m_emptyString;
#define JSC_COMMON_STRINGS_ATTRIBUTE_DECLARATION(name) JSString* m_##name;
JSC_COMMON_STRINGS_EACH_NAME(JSC_COMMON_STRINGS_ATTRIBUTE_DECLARATION)
#undef JSC_COMMON_STRINGS_ATTRIBUTE_DECLARATION
JSString* m_objectStringStart;
JSString* m_nullObjectString;
JSString* m_undefinedObjectString;
JSString* m_singleCharacterStrings[singleCharacterStringCount];
std::unique_ptr<SmallStringsStorage> m_storage;
bool m_needsToBeVisited;
};
} // namespace JSC
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