Request for reviews (S): 6880053 backport to HS16

[Vladimir Kozlov]

Than you, Tom

Vladimir

Tom Rodriguez wrote:
> Looks good.
> 
> tom
> 
> On Sep 17, 2009, at 6:51 PM, Vladimir Kozlov wrote:
> 
>> This is backport of the fix in HS17.
>>
>> http://cr.openjdk.java.net/~kvn/6880053_hs16/webrev.00
>>
>> Fixed 6880053: assert(alloc_obj->as_CheckCastPP()->type() != 
>> TypeInstPtr::NOTNULL)
>>
>> Problem:
>> Nightly testing found a case when the type
>> of the cloned object is TypeInstPtr::NOTNULL
>> the same as tyoe of second CheckCastPP node in clone()
>> intrinsic and arraycopy. It produces incorrect graph.
>>
>> Solution:
>> Removed second CheckCastPP and instead use MembarCPUOrder
>> to not let reads from the cloned object float above the arraycopy.
>>
>> Reviewed by:
>>
>> Fix verified (y/n): y, test
>>
>> Other testing:
>> JPRT
>>
>