[9] RFR(S): 8021775: compiler/8009761/Test8009761.java "Failed: init recursive calls: 51. After deopt 50"

[Tobias Hartmann]

Hi Chris,

thanks for the feedback.

On 16.05.2014 18:00, Christian Thalinger wrote:
>
> On May 16, 2014, at 4:29 AM, Tobias Hartmann 
> <tobias.hartmann at oracle.com <mailto:tobias.hartmann at oracle.com>> wrote:
>
>> Hi Chris,
>>
>> thanks for the review.
>>
>> On 15.05.2014 16:31, Christian Thalinger wrote:
>>> Presumably:
>>> *+          WHITE_BOX.enqueueMethodForCompilation(m3, COMP_LEVEL_FULL_OPTIMIZATION);*
>>> *+          if(!WHITE_BOX.isMethodCompiled(m3)) {*
>>> *+             throw new RuntimeException(m3 + " not compiled");*
>>>            }
>>> works because we’re using -XX:-BackgroundCompilation, correct? 
>>>  Maybe add a comment there. 
>>
>> Yes, exactly.
>>
>>>  Can we verify via WB API that BackgroundCompilation is off?
>>
>> Yes, this is for example done in 
>> CompilerWhiteBoxTest::getVMOption(...) to set BACKGROUND_COMPILATION. 
>> But I think because we explicitly disable background compilation in 
>> the test header it should not be possible to re-enable it, right?
>
> Correct but who knows what test cleanup might happen in the future. 
>  Maybe someday someone decides that we shouldn’t run tests with 
> -BackgroundCompilation.  This test is not easy to get right and had a 
> couple of issues already.  I want it fool proof.

Right. I added a method backgroundCompilationEnabled(...) to check if 
background compilation is enabled and explicitly check it in main.

New webrev: http://cr.openjdk.java.net/~anoll/8021775/webrev.01/

Thanks,
Tobias

>
>>
>> Thanks,
>> Tobias
>>
>>>
>>> I’m happy that using the WB API worked.
>>>
>>> On May 15, 2014, at 5:44 AM, Tobias Hartmann 
>>> <tobias.hartmann at oracle.com <mailto:tobias.hartmann at oracle.com>> wrote:
>>>
>>>> Hi,
>>>>
>>>> please review the following patch for 8021775.
>>>>
>>>> *Problem
>>>> *The compiler test for bug 8009761 checks if the stack size after 
>>>> deoptimization is the same as before by counting the number of 
>>>> possible recursive calls until a StackOverflowException occurs both 
>>>> before and after deoptimization. The test tries to trigger 
>>>> compilation by executing the method multiple times and enforces 
>>>> deoptimization by loading a previously unloaded class.
>>>>
>>>> The test fails on multiple platforms.*
>>>> *Bug: https://bugs.openjdk.java.net/browse/JDK-8021775
>>>>
>>>> *Solution**
>>>> *The test seems to be unstable, as there already occurred several 
>>>> test bugs (see 8010399 and 8012037). Enforcing compilation by 
>>>> executing a method multiple times is indeterministic. We have to 
>>>> make sure that the method is compiled and deoptimized exactly at 
>>>> those points in time where it is needed.
>>>>
>>>> I reimplemented the test using the Whitebox API to 
>>>> deterministically trigger compilation and deoptimization.
>>>> Webrev: http://cr.openjdk.java.net/~anoll/8021775/webrev.00/
>>>> *
>>>> **Tests*
>>>> Executed test on machines where it previously failed (1k runs, no 
>>>> fails).
>>>>
>>>> Thanks,
>>>> Tobias
>>>
>>
>

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