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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) const
+{
+ ASSERT(!isCell());
+
+ if (isInt32() || isDouble())
+ return constructNumber(exec, asValue());
+ if (isTrue() || isFalse())
+ return constructBooleanFromImmediateBoolean(exec, 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, asValue());
+ if (isTrue() || isFalse())
+ return constructBooleanFromImmediateBoolean(exec, asValue());
+ ASSERT(isUndefinedOrNull());
+ return exec->globalThisValue();
+}
+
+JSObject* JSValue::synthesizeObject(ExecState* exec) const
+{
+ ASSERT(!isCell());
+ if (isNumber())
+ return constructNumber(exec, asValue());
+ if (isBoolean())
+ return constructBooleanFromImmediateBoolean(exec, 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