[9] RFR (S): 8150186: Folding mismatched accesses with @Stable is incorrect

[Vladimir Kozlov]

Looks good.

Test: Copyright 2016.

Thanks,
Vladimir

On 2/24/16 8:06 AM, Vladimir Ivanov wrote:
> http://cr.openjdk.java.net/~vlivanov/8150186/webrev.00/
> https://bugs.openjdk.java.net/browse/JDK-8150186
>
> Constant folding from stable arrays doesn't check for mismatched accesses.
>
> The fix is to disable the optimization for mismatched accesses.
>
> Also, added missing range checks in ciArray::element_value_by_offset.
>
> Testing: failing tests, JPRT
>
> Best regards,
> Vladimir Ivanov
>
> PS: I considered converting is_mismatched_access check in
> fold_stable_ary_elem into an assert, but I spotted some quirks in
> mismatched access detection (filed JDK-8150543 [1]). So, I'd prefer to
> keep the check and refine the code as part of JDK-8150543 when more test
> coverage is available.
>
> [1] https://bugs.openjdk.java.net/browse/JDK-8150543