RFR(M): 8076188 Optimize arraycopy out for non escaping destination

[Vladimir Ivanov]

Still looks fine.

Best regards,
Vladimir Ivanov

On 5/12/15 1:40 PM, Roland Westrelin wrote:
>
> jprt found some problems with this change. So I’d like to push:
>
> http://cr.openjdk.java.net/~roland/8076188/webrev.00-01/
>
> on top of the reviewed change. Overall change:
>
> http://cr.openjdk.java.net/~roland/8076188/webrev.01/
>
> List of fixes:
>
> - tests with G1 failed in verification code. I made the change to LoadNode::Ideal() so the new code that looks for a dominating identical load is disabled for raw loads
>
> - OptimizePtrCompare is broken in cases like the new test case added to TestEliminateArrayCopy.java: field from non escaping object should have an unknown value when the the object is target of an ArrayCopy.
>
> - The ifnode change is unrelated (I found the problem when debugging one of the issues above) but it’s simple enough that I don’t think it needs its own CR.
>
> Roland.
>
>> On Apr 29, 2015, at 11:30 AM, Roland Westrelin <roland.westrelin at oracle.com> wrote:
>>
>> Thanks for the review, Vladimir.
>>
>> Roland.
>>
>>> On Apr 28, 2015, at 4:42 PM, Vladimir Ivanov <vladimir.x.ivanov at oracle.com> wrote:
>>>
>>> Looks good.
>>>
>>> Best regards,
>>> Vladimir Ivanov
>>>
>>> On 4/21/15 4:02 PM, Roland Westrelin wrote:
>>>> http://cr.openjdk.java.net/~roland/8076188/webrev.00/
>>>>
>>>> This patch tries to eliminate ArrayCopyNodes (for instance clones, array clones, arraycopy and copyOf) when the destination of the copy doesn’t escape:
>>>>
>>>> - during escape analysis, ArrayCopyNodes don’t cause the destination of the copy to be marked as escaping anymore
>>>> - a load to the destination of a copy may be replaced by a load from the source during IGVN
>>>> - during macro expansion, ArrayCopyNodes don’t stop allocation from being eliminated and can themselves be eliminated
>>>>
>>>> Roland.
>>>>
>>
>