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]

You also don't need the /othervm part.

tom

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