#ifndef ParserArena_h
#define ParserArena_h
#include "Identifier.h"
#include <wtf/SegmentedVector.h>
namespace JSC {
class ParserArenaDeletable;
class ParserArenaRefCounted;
class IdentifierArena {
WTF_MAKE_FAST_ALLOCATED;
public:
IdentifierArena()
{
clear();
}
template <typename T>
ALWAYS_INLINE const Identifier& makeIdentifier(VM*, const T* characters, size_t length);
ALWAYS_INLINE const Identifier& makeIdentifierLCharFromUChar(VM*, const UChar* characters, size_t length);
const Identifier& makeNumericIdentifier(VM*, double number);
bool isEmpty() const { return m_identifiers.isEmpty(); }
public:
static const int MaximumCachableCharacter = 128;
typedef SegmentedVector<Identifier, 64> IdentifierVector;
void clear()
{
m_identifiers.clear();
for (int i = 0; i < MaximumCachableCharacter; i++)
m_shortIdentifiers[i] = 0;
for (int i = 0; i < MaximumCachableCharacter; i++)
m_recentIdentifiers[i] = 0;
}
private:
IdentifierVector m_identifiers;
FixedArray<Identifier*, MaximumCachableCharacter> m_shortIdentifiers;
FixedArray<Identifier*, MaximumCachableCharacter> m_recentIdentifiers;
};
template <typename T>
ALWAYS_INLINE const Identifier& IdentifierArena::makeIdentifier(VM* vm, const T* characters, size_t length)
{
if (characters[0] >= MaximumCachableCharacter) {
m_identifiers.append(Identifier(vm, characters, length));
return m_identifiers.last();
}
if (length == 1) {
if (Identifier* ident = m_shortIdentifiers[characters[0]])
return *ident;
m_identifiers.append(Identifier(vm, characters, length));
m_shortIdentifiers[characters[0]] = &m_identifiers.last();
return m_identifiers.last();
}
Identifier* ident = m_recentIdentifiers[characters[0]];
if (ident && Identifier::equal(ident->impl(), characters, length))
return *ident;
m_identifiers.append(Identifier(vm, characters, length));
m_recentIdentifiers[characters[0]] = &m_identifiers.last();
return m_identifiers.last();
}
ALWAYS_INLINE const Identifier& IdentifierArena::makeIdentifierLCharFromUChar(VM* vm, const UChar* characters, size_t length)
{
if (characters[0] >= MaximumCachableCharacter) {
m_identifiers.append(Identifier::createLCharFromUChar(vm, characters, length));
return m_identifiers.last();
}
if (length == 1) {
if (Identifier* ident = m_shortIdentifiers[characters[0]])
return *ident;
m_identifiers.append(Identifier(vm, characters, length));
m_shortIdentifiers[characters[0]] = &m_identifiers.last();
return m_identifiers.last();
}
Identifier* ident = m_recentIdentifiers[characters[0]];
if (ident && Identifier::equal(ident->impl(), characters, length))
return *ident;
m_identifiers.append(Identifier::createLCharFromUChar(vm, characters, length));
m_recentIdentifiers[characters[0]] = &m_identifiers.last();
return m_identifiers.last();
}
inline const Identifier& IdentifierArena::makeNumericIdentifier(VM* vm, double number)
{
m_identifiers.append(Identifier(vm, String::numberToStringECMAScript(number)));
return m_identifiers.last();
}
class ParserArena {
WTF_MAKE_NONCOPYABLE(ParserArena);
public:
ParserArena();
~ParserArena();
void swap(ParserArena& otherArena)
{
std::swap(m_freeableMemory, otherArena.m_freeableMemory);
std::swap(m_freeablePoolEnd, otherArena.m_freeablePoolEnd);
m_identifierArena.swap(otherArena.m_identifierArena);
m_freeablePools.swap(otherArena.m_freeablePools);
m_deletableObjects.swap(otherArena.m_deletableObjects);
m_refCountedObjects.swap(otherArena.m_refCountedObjects);
}
void* allocateFreeable(size_t size)
{
ASSERT(size);
ASSERT(size <= freeablePoolSize);
size_t alignedSize = alignSize(size);
ASSERT(alignedSize <= freeablePoolSize);
if (UNLIKELY(static_cast<size_t>(m_freeablePoolEnd - m_freeableMemory) < alignedSize))
allocateFreeablePool();
void* block = m_freeableMemory;
m_freeableMemory += alignedSize;
return block;
}
void* allocateDeletable(size_t size)
{
ParserArenaDeletable* deletable = static_cast<ParserArenaDeletable*>(allocateFreeable(size));
m_deletableObjects.append(deletable);
return deletable;
}
void derefWithArena(PassRefPtr<ParserArenaRefCounted>);
bool contains(ParserArenaRefCounted*) const;
ParserArenaRefCounted* last() const;
void removeLast();
bool isEmpty() const;
JS_EXPORT_PRIVATE void reset();
IdentifierArena& identifierArena()
{
if (UNLIKELY (!m_identifierArena))
m_identifierArena = adoptPtr(new IdentifierArena);
return *m_identifierArena;
}
private:
static const size_t freeablePoolSize = 8000;
static size_t alignSize(size_t size)
{
return (size + sizeof(WTF::AllocAlignmentInteger) - 1) & ~(sizeof(WTF::AllocAlignmentInteger) - 1);
}
void* freeablePool();
void allocateFreeablePool();
void deallocateObjects();
char* m_freeableMemory;
char* m_freeablePoolEnd;
OwnPtr<IdentifierArena> m_identifierArena;
Vector<void*> m_freeablePools;
Vector<ParserArenaDeletable*> m_deletableObjects;
Vector<RefPtr<ParserArenaRefCounted> > m_refCountedObjects;
};
}
#endif