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

[Stefan Karlsson]

Hi Vladimir,

What do you think about this version:
  http://cr.openjdk.java.net/~stefank/8140584/webrev.02/
  http://cr.openjdk.java.net/~stefank/8140584/webrev.02.delta/

Thanks,
StefanK

On 2015-10-30 09:44, Vladimir Kozlov wrote:
> 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
>>