Request for Review (S) 6852078: HSX 14/16 in jdk 5.0: api/javax_management api/org_omg jck tests crashes or make tnameserv crash

[Paul Hohensee]

Looks ok to me also.

Paul

Vladimir Kozlov wrote:
> OK.
>
> Vladimir
>
> Changpeng Fang wrote:
>> On 10/29/09 17:18, Vladimir Kozlov wrote:
>>> I don't think having assert there is correct
>>> since there is nothing wrong with ideal graph.
>>>
>> 1924   //unsafe reference could not be aligned appropriately without 
>> runtime checking
>> 1925   if (base == NULL || base->bottom_type() == Type::TOP) {
>> 1926     assert(!valid(), "unsafe access");
>> 1927     return;
>> 1928   }
>>
>>
>> The assert is nothing related to ideal graph. It just makes sure that 
>> the SWPointer returned from
>> here is not useable. You may see many places that use 
>> SWPointer::valid() checking before  doing
>> actual thing (alignment, for example).
>>
>> Thanks,
>>
>> Changpeng
>>
>>
>>> Vladimir
>>>
>>> Changpeng Fang wrote:
>>>> Was sent  to the gc mailing list. Resend to the correct compiler 
>>>> list. Thanks,
>>>>
>>>>> http://cr.openjdk.java.net/~cfang/6852078/webrev.00/
>>>>>
>>>>> Note that I am requesting for change to the current jdk source 
>>>>> (For the SubCR)
>>>>>
>>>>> 6852078: HSX 14/16 in jdk 5.0: api/javax_management api/org_omg 
>>>>> jck tests crashes or make tnameserv crash
>>>>>
>>>>> Problem: Current implementation of superword optimization does not 
>>>>> check for unsafe memory accesses. Since
>>>>> unsafe memory accesses could not be aligned appropriately without 
>>>>> runtime checking, a un-aligned superword
>>>>> read/write could cause runtime failure.
>>>>>
>>>>> Solution: Simply disable superword for unsafe memory access whose 
>>>>> base is top.
>>>>>
>>>>> Tests: Test case in 6852078
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Changpeng
>>>>>
>>>>>
>>>>
>>