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/*
* Copyright (C) 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.
*/
#ifndef FunctionRareData_h
#define FunctionRareData_h
#include "InternalFunctionAllocationProfile.h"
#include "JSCell.h"
#include "ObjectAllocationProfile.h"
#include "Watchpoint.h"
namespace JSC {
class JSGlobalObject;
class LLIntOffsetsExtractor;
namespace DFG {
class SpeculativeJIT;
class JITCompiler;
}
class FunctionRareData : public JSCell {
friend class JIT;
friend class DFG::SpeculativeJIT;
friend class DFG::JITCompiler;
friend class VM;
public:
typedef JSCell Base;
static const unsigned StructureFlags = StructureIsImmortal | Base::StructureFlags;
static FunctionRareData* create(VM&);
static const bool needsDestruction = true;
static void destroy(JSCell*);
static Structure* createStructure(VM&, JSGlobalObject*, JSValue prototype);
static void visitChildren(JSCell*, SlotVisitor&);
DECLARE_INFO;
static inline ptrdiff_t offsetOfObjectAllocationProfile()
{
return OBJECT_OFFSETOF(FunctionRareData, m_objectAllocationProfile);
}
ObjectAllocationProfile* objectAllocationProfile()
{
return &m_objectAllocationProfile;
}
Structure* objectAllocationStructure() { return m_objectAllocationProfile.structure(); }
InlineWatchpointSet& allocationProfileWatchpointSet()
{
return m_objectAllocationProfileWatchpoint;
}
void clear(const char* reason);
void initializeObjectAllocationProfile(VM&, JSObject* prototype, size_t inlineCapacity);
bool isObjectAllocationProfileInitialized() { return !m_objectAllocationProfile.isNull(); }
Structure* internalFunctionAllocationStructure() { return m_internalFunctionAllocationProfile.structure(); }
Structure* createInternalFunctionAllocationStructureFromBase(VM& vm, JSObject* prototype, Structure* baseStructure)
{
return m_internalFunctionAllocationProfile.createAllocationStructureFromBase(vm, this, prototype, baseStructure);
}
protected:
FunctionRareData(VM&);
~FunctionRareData();
private:
friend class LLIntOffsetsExtractor;
// Ideally, there would only be one allocation profile for subclassing but due to Reflect.construct we
// have two. There are some pros and cons in comparison to our current system to using the same profile
// for both JS constructors and subclasses of builtin constructors:
//
// 1) + Uses less memory.
// 2) + Conceptually simplier as there is only one profile.
// 3) - We would need a check in all JSFunction object creations (both with classes and without) that the
// new.target's profiled structure has a JSFinalObject ClassInfo. This is needed, for example, if we have
// `Reflect.construct(Array, args, myConstructor)` since myConstructor will be the new.target of Array
// the Array constructor will set the allocation profile of myConstructor to hold an Array structure
//
// We don't really care about 1) since this memory is rare and small in total. 2) is unfortunate but is
// probably outweighed by the cost of 3).
ObjectAllocationProfile m_objectAllocationProfile;
InlineWatchpointSet m_objectAllocationProfileWatchpoint;
InternalFunctionAllocationProfile m_internalFunctionAllocationProfile;
};
} // namespace JSC
#endif // FunctionRareData_h
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