blob: 1ec31a4118842aed6c26af37c93d98219ccb5cdd [file] [log] [blame]
/*
* Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
* Copyright (C) 2003-2017 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#pragma once
#include "CallFrame.h"
#include <wtf/CheckedArithmetic.h>
#include <wtf/ForbidHeapAllocation.h>
#include <wtf/HashSet.h>
namespace JSC {
class MarkedArgumentBuffer : public RecordOverflow {
WTF_MAKE_NONCOPYABLE(MarkedArgumentBuffer);
WTF_FORBID_HEAP_ALLOCATION;
friend class VM;
friend class ArgList;
public:
using Base = RecordOverflow;
static const size_t inlineCapacity = 8;
typedef HashSet<MarkedArgumentBuffer*> ListSet;
// Constructor for a read-write list, to which you may append values.
// FIXME: Remove all clients of this API, then remove this API.
MarkedArgumentBuffer()
: m_size(0)
, m_capacity(inlineCapacity)
, m_buffer(m_inlineBuffer)
, m_markSet(0)
{
}
~MarkedArgumentBuffer()
{
ASSERT(!m_needsOverflowCheck);
if (m_markSet)
m_markSet->remove(this);
if (EncodedJSValue* base = mallocBase())
Gigacage::free(Gigacage::JSValue, base);
}
size_t size() const { return m_size; }
bool isEmpty() const { return !m_size; }
JSValue at(int i) const
{
if (i >= m_size)
return jsUndefined();
return JSValue::decode(slotFor(i));
}
void clear()
{
ASSERT(!m_needsOverflowCheck);
clearOverflow();
m_size = 0;
}
enum OverflowCheckAction {
CrashOnOverflow,
WillCheckLater
};
template<OverflowCheckAction action>
void appendWithAction(JSValue v)
{
ASSERT(m_size <= m_capacity);
if (m_size == m_capacity || mallocBase()) {
slowAppend(v);
if (action == CrashOnOverflow)
RELEASE_ASSERT(!hasOverflowed());
return;
}
slotFor(m_size) = JSValue::encode(v);
++m_size;
}
void append(JSValue v) { appendWithAction<WillCheckLater>(v); }
void appendWithCrashOnOverflow(JSValue v) { appendWithAction<CrashOnOverflow>(v); }
void removeLast()
{
ASSERT(m_size);
m_size--;
}
JSValue last()
{
ASSERT(m_size);
return JSValue::decode(slotFor(m_size - 1));
}
JSValue takeLast()
{
JSValue result = last();
removeLast();
return result;
}
static void markLists(SlotVisitor&, ListSet&);
void ensureCapacity(size_t requestedCapacity)
{
if (requestedCapacity > static_cast<size_t>(m_capacity))
slowEnsureCapacity(requestedCapacity);
}
bool hasOverflowed()
{
clearNeedsOverflowCheck();
return Base::hasOverflowed();
}
void overflowCheckNotNeeded() { clearNeedsOverflowCheck(); }
private:
void expandCapacity();
void expandCapacity(int newCapacity);
void slowEnsureCapacity(size_t requestedCapacity);
void addMarkSet(JSValue);
JS_EXPORT_PRIVATE void slowAppend(JSValue);
EncodedJSValue& slotFor(int item) const
{
return m_buffer[item];
}
EncodedJSValue* mallocBase()
{
if (m_buffer == m_inlineBuffer)
return 0;
return &slotFor(0);
}
#if ASSERT_DISABLED
void setNeedsOverflowCheck() { }
void clearNeedsOverflowCheck() { }
#else
void setNeedsOverflowCheck() { m_needsOverflowCheck = true; }
void clearNeedsOverflowCheck() { m_needsOverflowCheck = false; }
bool m_needsOverflowCheck { false };
#endif
int m_size;
int m_capacity;
EncodedJSValue m_inlineBuffer[inlineCapacity];
EncodedJSValue* m_buffer;
ListSet* m_markSet;
};
class ArgList {
WTF_MAKE_FAST_ALLOCATED;
friend class Interpreter;
friend class JIT;
public:
ArgList()
: m_args(0)
, m_argCount(0)
{
}
ArgList(ExecState* exec)
: m_args(reinterpret_cast<JSValue*>(&exec[CallFrame::argumentOffset(0)]))
, m_argCount(exec->argumentCount())
{
}
ArgList(const MarkedArgumentBuffer& args)
: m_args(reinterpret_cast<JSValue*>(args.m_buffer))
, m_argCount(args.size())
{
}
JSValue at(int i) const
{
if (i >= m_argCount)
return jsUndefined();
return m_args[i];
}
bool isEmpty() const { return !m_argCount; }
size_t size() const { return m_argCount; }
JS_EXPORT_PRIVATE void getSlice(int startIndex, ArgList& result) const;
private:
JSValue* data() const { return m_args; }
JSValue* m_args;
int m_argCount;
};
} // namespace JSC