/* * 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