Request for reviews (XS): 6866651: Regression: simple int sum crashes jvm (build 1.6.0_14-b08 and 1.7.0-ea-b59)

[changpeng fang - Sun Microsystems - Santa Clara United States]

On 08/17/09 08:22, Tom Rodriguez wrote:
> No regression test should crash unless there is a bug so I don't see 
> that it makes much difference.  The tests run more quickly without 
> othervm so it's preferred not to use it.
>
So, should we do clean-up in test/compiler regression test suite? I have 
seen most of the tests use /othervm.

Thanks,

Changpeng


> tom
>
> On Aug 15, 2009, at 5:01 PM, John Coomes wrote:
>
>> Tom Rodriguez (Thomas.Rodriguez at Sun.COM) wrote:
>>> You also don't need the /othervm part.
>>
>> Minor point, but isn't it polite to use /othervm for a test that could
>> cause a crash?  If it's run in the same vm, a crash would bring down
>> the harness.
>>
>> -John
>>
>>> On Aug 14, 2009, at 3:09 PM, Vladimir Kozlov wrote:
>>>
>>>> Looks good.
>>>>
>>>> I would remove -server from the test options to run it with tested
>>>> (client) VM instead of default VM.
>>>>
>>>> Thanks,
>>>> Vladimir
>>>>
>>>> changpeng fang - Sun Microsystems - Santa Clara United States wrote:
>>>>> http://cr.openjdk.java.net/~cfang/6866651/webrev.00/
>>>>> Fixed 6866651: Regression: simple int sum crashes jvm (build
>>>>> 1.6.0_14-b08 and 1.7.0-ea-b59)
>>>>> Problem:
>>>>> set_req_X will do dead code elimination if the original input has
>>>>> no other use. However, it is possible to
>>>>> have the current node (this) removed if a dead loop exists.  So,
>>>>> dead code elimination in set_req_X is not
>>>>> safe, and may  cause undesired consequences (like the segfault in
>>>>> 6866651)
>>>>> Solution:
>>>>> Instead of doing dead code elimination immediately in set_req_X, we
>>>>> put the dead node (original input) into
>>>>> the worklist, and the dead node will eventually be eliminated when
>>>>> it is its turn to be processed.
>>>>> In addition,  before ideal transformations, we replace a node with
>>>>> a constant if we know it computes a constant
>>>>> to skip unneeded optimizations on this node.
>>>>> Tests: JPRT, CompileTheWorld, Test case in bug report (Test.java in
>>>>> webrev)
>>>>> Thanks,
>>>>> Changpeng
>>>
>>
>