Please review JDK-8061391

[Hannes Wallnoefer]

DeletedRangeArrayFilter.isEmpty should not override ArrayData.isEmpty as 
semantics are different. The easiest way to solve this would be to move 
new isEmpty method from ArrayData to ContinuousArrayData.

Otherwise +1, nice work!

Hannes

Am 2014-10-22 um 17:34 schrieb Marcus Lagergren:
> Please review this
>
> I added specialized builtins for concat, which are up to 10 times faster in microbenchmarks with just one element (or array) being concatenated.
> While doing this I happened upon some bugs with preventExtensions for arrays, and removed the hateful unreliable SwitchPoint from ContinuousArray, replacing non extensible arrays with an ArrayFilter, which is the way I should have done it in the first place.
> I also had to turn NoTypedArrayData into a structure that inherited ContinuousArray, or I threw away a lot of optimistic link sites to untouched arrays in ScriptObjects. This has other performance implications (good ones).
>
> ant test runs cleanly
> ant test262parallel runs cleanly
> octane runs with no regressions, some benchmarks like raytrace and crypto are even a bit faster.
>
> There are regressions in octane since the last time I checked, but not due to my fix. I will investigate and file bugs.
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8061391
> Webrev: http://cr.openjdk.java.net/~lagergren/8061391/
>
> Regards
> Marcus