[9] RFR (XS): 8058847: C2: EliminateAutoBox regression after 8042786

[Vladimir Kozlov]

Looks good. Thank you for fixing this.

Vladimir K

On 10/23/14 11:21 AM, Vladimir Ivanov wrote:
> http://cr.openjdk.java.net/~vlivanov/8058847/webrev.00/
> https://bugs.openjdk.java.net/browse/JDK-8058847
>
> LoadNode::eliminate_autobox() doesn't care whether the unboxing node represents signed or unsigned load. It means that
> for LoadUB/LoadUS -> ... -> LoadB/LoadS unboxing/boxing pair, information about unsigned load is lost. It leads to
> incorrect code generation.
>
> The fix is to reify this information in the graph by wrapping the result in AddI (_ mask).
>
> Testing: regression test
>
> Best regards,
> Vladimir Ivanov