RFR: 8140584: nmethod::oops_do_marking_epilogue always runs verification code

[Vladimir Kozlov]

On 10/29/15 11:52 PM, Stefan Karlsson wrote:
> Hi Vladimir,
>
> On 2015-10-27 16:22, Vladimir Kozlov wrote:
>> CodeCache::verify_oops() also calls it unguarded.
>>
>> I think for complete solution nmethod::verify_oop_relocations() and
>> called from it oop_Relocation::verify_oop_relocation(),
>> verify_value(), const_verify_data_value() and pd_verify_data_value()
>> should be declared and defined in debug build only.
>
> I see what you're saying, but I'm unsure that this is really what we
> want to do.
>
> CodeCache::verify_oops is called from the Universe::verify, that can be
> enabled in product builds by setting -XX:+UnlockDiagnosticVMOptions and
> -XX:+VerifyBeforeGC and/or -XX:+VerifyAfterGC. Maybe we want to change
> the relocation code to use guarantees instead of asserts? So that we can
> get verification of the relocation code in product builds?

Yes, I think it is good suggestion (asserts -> guarantees or fatals) in 
addition to webrev.01.

Thanks,
Vladimir

>
> Thanks,
> StefanK
>
>>
>> Thanks,
>> Vladimir
>>
>> On 10/27/15 7:44 PM, Stefan Karlsson wrote:
>>> Hi,
>>>
>>> Please review this patch to remove some unnecessary verification code
>>> from our product builds.
>>>
>>> Today, CodeCache::gc_epilogue() guards the call to
>>> nmethod::verify_oop_relocations with DEBUG_ONLY, while
>>> nmethod::oops_do_marking_epilogue doesn't. Since
>>> nmethod::verify_oop_relocations uses asserts when verifying the
>>> relocations, this is just wasted cycles in product builds. This patch
>>> adds DEBUG_ONLY to nmethod::oops_do_marking_epilogue.
>>>
>>> http://cr.openjdk.java.net/~stefank/8140584/webrev.01/
>>> https://bugs.openjdk.java.net/browse/JDK-8140584
>>>
>>> Thanks,
>>> StefanK
>