[9] RFR (M): 8143407: C1: @Stable array support

[Vladimir Ivanov]

Any reviews, please?

Best regards,
Vladimir Ivanov

On 2/19/16 9:34 PM, Vladimir Ivanov wrote:
> http://cr.openjdk.java.net/~vlivanov/8143407/webrev.01
> https://bugs.openjdk.java.net/browse/JDK-8143407
>
> Add C1 support for constant folding loads from @Stable arrays.
> It aligns C1 & C2 behavior w.r.t. @Stable fields and was requested for
> VarHandles [1] implementation.
>
> I introduced StableArrayConstant to track stable array dimension.
>
> It is needed to disambiguate the following cases:
>   (1) @Stable int[][][] intArr = new int[...][...][...];
>   (2) @Stable  Object[] objArr = new int[...][...][...];
>
> In the first case, all elements of multi-dimensional array w/
> non-default values are considered constant.
>
> In the latter, only elements of objArray (which are int[][] instances).
>
> Testing: unit tests on @Stable support, JPRT.
>
> Thanks!
>
> Best regards,
> Vladimir Ivanov
>
> [1] http://openjdk.java.net/jeps/193