Imported WebKit commit 2ea9d364d0f6efa8fa64acf19f451504c59be0e4 (http://svn.webkit.org/repository/webkit/trunk@104285)

1 files changed, 231 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/runtime/JSValue.cpp b/Source/JavaScriptCore/runtime/JSValue.cpp
new file mode 100644
index 000000000..a5d3d936a
--- /dev/null
+++ b/Source/JavaScriptCore/runtime/JSValue.cpp
@@ -0,0 +1,231 @@
+/*
+ *  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));
+}
+
+double JSValue::toNumberSlowCase(ExecState* exec) const
+{
+    ASSERT(!isInt32() && !isDouble());
+    if (isCell())
+        return asCell()->toNumber(exec);
+    if (isTrue())
+        return 1.0;
+    return isUndefined() ? std::numeric_limits<double>::quiet_NaN() : 0; // null and false both convert to 0.
+}
+
+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 JSNotAnObject::create(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 JSNotAnObject::create(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 JSNotAnObject::create(exec);
+}
+
+#ifndef NDEBUG
+char* JSValue::description()
+{
+    static const size_t size = 64;
+    static char description[size];
+
+    if (!*this)
+        snprintf(description, size, "<JSValue()>");
+    else if (isInt32())
+        snprintf(description, size, "Int32: %d", asInt32());
+    else if (isDouble()) {
+#if USE(JSVALUE64)
+        snprintf(description, size, "Double: %lf, %lx", asDouble(), reinterpretDoubleToIntptr(asDouble()));
+#else
+        union {
+            double asDouble;
+            uint32_t asTwoInt32s[2];
+        } u;
+        u.asDouble = asDouble();
+        snprintf(description, size, "Double: %lf, %08x:%08x", asDouble(), u.asTwoInt32s[1], u.asTwoInt32s[0]);
+#endif
+    } 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;
+}
+
+bool JSValue::isValidCallee()
+{
+    return asObject(asCell())->globalObject();
+}
+
+JSString* JSValue::toPrimitiveString(ExecState* exec) const
+{
+    if (isString())
+        return static_cast<JSString*>(asCell());
+    if (isInt32())
+        return jsString(&exec->globalData(), exec->globalData().numericStrings.add(asInt32()));
+    if (isDouble())
+        return jsString(&exec->globalData(), exec->globalData().numericStrings.add(asDouble()));
+    if (isTrue())
+        return jsNontrivialString(exec, exec->propertyNames().trueKeyword.ustring());
+    if (isFalse())
+        return jsNontrivialString(exec, exec->propertyNames().falseKeyword.ustring());
+    if (isNull())
+        return jsNontrivialString(exec, exec->propertyNames().nullKeyword.ustring());
+    if (isUndefined())
+        return jsNontrivialString(exec, exec->propertyNames().undefined.ustring());
+
+    ASSERT(isCell());
+    JSValue v = asCell()->toPrimitive(exec, NoPreference);
+    if (v.isString())
+        return static_cast<JSString*>(v.asCell());
+    return jsString(&exec->globalData(), v.toString(exec));
+}
+
+} // namespace JSC