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

[Tom Rodriguez]

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.

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
>>
>