RFR(M): 6700100: optimize inline_native_clone() for small objects with exact klass

[Roland Westrelin]

Vladimir,

Here is a new webrev that takes your comments into account:

http://cr.openjdk.java.net/~roland/6700100/webrev.01/

I moved the ik->has_injected_fields() call last in ArrayCopyNode::get_count() and added a comment.

I improved the code in fieldStreams.hpp

LibraryCallKit::inline_arraycopy() had what turned out to be the fix for JDK-8060252 (performance regression on sparc). I removed it so it can be pushed as a separate fix.

Roland.


> On Oct 10, 2014, at 9:31 PM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
> 
> I was thinking aloud :)
> 
> Changes are good as it is. Thank you for discussion.
> 
> Thanks,
> Vladimir
> 
> On 10/10/14 10:47 AM, Roland Westrelin wrote:
>>>> If we wanted to delay that transformation, wouldn’t we also want a few passes of IGVN to happen before we do the transformation?
>>> 
>>> The thing which can be improved is klass exactness. Which will allow to skip adding dependency. That is what I was thinking. But it may only happen after CCP phase. But I really want to do this optimization before EA which will greatly benefit from it. Also if klass is exact during parsing we may do optimization during parsing too.
>> 
>> Ok. But I’m not sure if you’re suggesting a change or if it’s good as it is?
>> 
>> Roland.
>>