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/*
* Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
* Copyright (C) 2001 Peter Kelly (pmk@post.com)
* Copyright (C) 2003, 2007, 2008 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.
*
*/
#include "config.h"
#include "JSValue.h"
#include "BooleanConstructor.h"
#include "BooleanPrototype.h"
#include "Error.h"
#include "ExceptionHelpers.h"
#include "JSGlobalObject.h"
#include "JSFunction.h"
#include "JSNotAnObject.h"
#include "NumberObject.h"
#include <wtf/MathExtras.h>
#include <wtf/StringExtras.h>
namespace JSC {
static const double D32 = 4294967296.0;
// ECMA 9.4
double JSValue::toInteger(ExecState* exec) const
{
if (isInt32())
return asInt32();
double d = toNumber(exec);
return isnan(d) ? 0.0 : trunc(d);
}
double JSValue::toIntegerPreserveNaN(ExecState* exec) const
{
if (isInt32())
return asInt32();
return trunc(toNumber(exec));
}
JSObject* JSValue::toObjectSlowCase(ExecState* exec, JSGlobalObject* globalObject) const
{
ASSERT(!isCell());
if (isInt32() || isDouble())
return constructNumber(exec, globalObject, asValue());
if (isTrue() || isFalse())
return constructBooleanFromImmediateBoolean(exec, globalObject, asValue());
ASSERT(isUndefinedOrNull());
throwError(exec, createNotAnObjectError(exec, *this));
return new (exec) JSNotAnObject(exec);
}
JSObject* JSValue::toThisObjectSlowCase(ExecState* exec) const
{
ASSERT(!isCell());
if (isInt32() || isDouble())
return constructNumber(exec, exec->lexicalGlobalObject(), asValue());
if (isTrue() || isFalse())
return constructBooleanFromImmediateBoolean(exec, exec->lexicalGlobalObject(), asValue());
ASSERT(isUndefinedOrNull());
return exec->globalThisValue();
}
JSObject* JSValue::synthesizeObject(ExecState* exec) const
{
ASSERT(!isCell());
if (isNumber())
return constructNumber(exec, exec->lexicalGlobalObject(), asValue());
if (isBoolean())
return constructBooleanFromImmediateBoolean(exec, exec->lexicalGlobalObject(), asValue());
ASSERT(isUndefinedOrNull());
throwError(exec, createNotAnObjectError(exec, *this));
return new (exec) JSNotAnObject(exec);
}
JSObject* JSValue::synthesizePrototype(ExecState* exec) const
{
ASSERT(!isCell());
if (isNumber())
return exec->lexicalGlobalObject()->numberPrototype();
if (isBoolean())
return exec->lexicalGlobalObject()->booleanPrototype();
ASSERT(isUndefinedOrNull());
throwError(exec, createNotAnObjectError(exec, *this));
return new (exec) JSNotAnObject(exec);
}
#ifndef NDEBUG
char* JSValue::description()
{
static const size_t size = 32;
static char description[size];
if (!*this)
snprintf(description, size, "<JSValue()>");
else if (isInt32())
snprintf(description, size, "Int32: %d", asInt32());
else if (isDouble())
snprintf(description, size, "Double: %lf", asDouble());
else if (isCell())
snprintf(description, size, "Cell: %p", asCell());
else if (isTrue())
snprintf(description, size, "True");
else if (isFalse())
snprintf(description, size, "False");
else if (isNull())
snprintf(description, size, "Null");
else if (isUndefined())
snprintf(description, size, "Undefined");
else
snprintf(description, size, "INVALID");
return description;
}
#endif
// This in the ToInt32 operation is defined in section 9.5 of the ECMA-262 spec.
// Note that this operation is identical to ToUInt32 other than to interpretation
// of the resulting bit-pattern (as such this metod is also called to implement
// ToUInt32).
//
// The operation can be descibed as round towards zero, then select the 32 least
// bits of the resulting value in 2s-complement representation.
int32_t toInt32(double number)
{
int64_t bits = WTF::bitwise_cast<int64_t>(number);
int32_t exp = (static_cast<int32_t>(bits >> 52) & 0x7ff) - 0x3ff;
// If exponent < 0 there will be no bits to the left of the decimal point
// after rounding; if the exponent is > 83 then no bits of precision can be
// left in the low 32-bit range of the result (IEEE-754 doubles have 52 bits
// of fractional precision).
// Note this case handles 0, -0, and all infinte, NaN, & denormal value.
if (exp < 0 || exp > 83)
return 0;
// Select the appropriate 32-bits from the floating point mantissa. If the
// exponent is 52 then the bits we need to select are already aligned to the
// lowest bits of the 64-bit integer representation of tghe number, no need
// to shift. If the exponent is greater than 52 we need to shift the value
// left by (exp - 52), if the value is less than 52 we need to shift right
// accordingly.
int32_t result = (exp > 52)
? static_cast<int32_t>(bits << (exp - 52))
: static_cast<int32_t>(bits >> (52 - exp));
// IEEE-754 double precision values are stored omitting an implicit 1 before
// the decimal point; we need to reinsert this now. We may also the shifted
// invalid bits into the result that are not a part of the mantissa (the sign
// and exponent bits from the floatingpoint representation); mask these out.
if (exp < 32) {
int32_t missingOne = 1 << exp;
result &= missingOne - 1;
result += missingOne;
}
// If the input value was negative (we could test either 'number' or 'bits',
// but testing 'bits' is likely faster) invert the result appropriately.
return bits < 0 ? -result : result;
}
NEVER_INLINE double nonInlineNaN()
{
#if OS(SYMBIAN)
return nanval();
#else
return std::numeric_limits<double>::quiet_NaN();
#endif
}
bool JSValue::isValidCallee()
{
return asObject(asObject(asCell())->getAnonymousValue(0))->isGlobalObject();
}
} // namespace JSC
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