diff options
Diffstat (limited to 'src/jdk/nashorn/internal/runtime/JSType.java')
| -rw-r--r-- | src/jdk/nashorn/internal/runtime/JSType.java | 28 |
1 files changed, 18 insertions, 10 deletions
diff --git a/src/jdk/nashorn/internal/runtime/JSType.java b/src/jdk/nashorn/internal/runtime/JSType.java index 21977816..e972a99e 100644 --- a/src/jdk/nashorn/internal/runtime/JSType.java +++ b/src/jdk/nashorn/internal/runtime/JSType.java @@ -102,6 +102,8 @@ public enum JSType { /** JavaScript compliant conversion function from Object to primitive */ public static final Call TO_PRIMITIVE = staticCall(JSType.class, "toPrimitive", Object.class, Object.class); + private static final double INT32_LIMIT = 4294967296.0; + /** * The external type name as returned by ECMAScript "typeof" operator * @@ -612,10 +614,7 @@ public enum JSType { * @return an int32 */ public static int toInt32(final double num) { - if (Double.isInfinite(num)) { - return 0; - } - return (int)(long)num; + return (int)doubleToInt32(num); } /** @@ -658,10 +657,7 @@ public enum JSType { * @return a uint32 */ public static long toUint32(final double num) { - if (Double.isInfinite(num)) { - return 0L; - } - return ((long)num) & 0xffff_ffffL; + return doubleToInt32(num) & MAX_UINT; } /** @@ -702,10 +698,22 @@ public enum JSType { * @return a uint16 */ public static int toUint16(final double num) { - if (Double.isInfinite(num)) { + return ((int)doubleToInt32(num)) & 0xffff; + } + + private static long doubleToInt32(final double num) { + final int exponent = Math.getExponent(num); + if (exponent < 31) { + return (long) num; // Fits into 32 bits + } + if (exponent >= 84) { + // Either infinite or NaN or so large that shift / modulo will produce 0 + // (52 bit mantissa + 32 bit target width). return 0; } - return ((int)(long)num) & 0xffff; + // This is rather slow and could probably be sped up using bit-fiddling. + final double d = (num >= 0) ? Math.floor(num) : Math.ceil(num); + return (long)(d % INT32_LIMIT); } /** |