Request for review: 8009595: The UseSplitVerifier option needs to be deprecated

[harold seigel]

Hi Remi,

Would it be helpful if, in JDK8, -XX:-UseSplitVerifier was allowed for 
classfile versions <= 51, but not for classfile versions > 51?

Thanks, Harold

On 3/8/2013 3:36 AM, Remi Forax wrote:
> On 03/08/2013 05:02 AM, Krystal Mo wrote:
>> There has been a workaround for folks upgrading to JDK7 that involves 
>> -XX:-UseSplitVerifier:
>> If they were using some older version of bytecode manipulation 
>> libraries (e.g. AspectJ), then those libraries may generate class 
>> files without stackmaps but tagged as version 51 (which is required 
>> to use the new verifier).
>>
>> That said, as a major release I believe it's okay to deprecate this 
>> flag in JDK8.
>>
>> Thanks,
>> Kris
>
> Is there a real need to deprecate this flag, maybe you should just 
> moving it to non product flags ?
> It's a knob very convenient for people like me that generate bytecode 
> at runtime and want to debug stack frames created by hand.
>
> cheers,
> Rémi
>
>>
>> On 2013/3/7 19:04, Daniel D. Daugherty wrote:
>>> > Open webrev at http://cr.openjdk.java.net/~hseigel/bug_8009595/
>>>
>>> Thumbs up.
>>>
>>> src/share/vm/classfile/classFileParser.cpp
>>>     No comments.
>>>
>>> src/share/vm/classfile/verifier.cpp
>>>     So we still call the older verifier for pre-stackmap class files.
>>>
>>> src/share/vm/runtime/arguments.cpp
>>>     I didn't even know about this table. Cool.
>>>
>>> src/share/vm/runtime/globals.hpp
>>>     One less option!
>>>
>>> The bug says that WLS is no longer using the flag. Is there anyone
>>> else that is using the flag? Since JDK8 is a major release do we
>>> care if anyone is using it?
>>>
>>> So we have any tests that are explicitly using either
>>> -XX:+UseSplitVerifier or -XX:-UseSplitVerifier? My grep didn't
>>> find any in the HotSpot repo, but I didn't check the
>>> 'jdk' repo nor the JCK tests.
>>>
>>> Dan
>>>
>>>
>>>
>>> On 3/7/13 5:52 PM, harold seigel wrote:
>>>> Hi,
>>>>
>>>> Please review this small change to obsolete the UseSplitVerifier 
>>>> option.
>>>>
>>>> Summary:
>>>> The UseSplitVerifier option has been added to the 
>>>> obsolete_jvm_flags table and its use removed everywhere else.
>>>>
>>>> Open webrev at http://cr.openjdk.java.net/~hseigel/bug_8009595/ 
>>>> <http://cr.openjdk.java.net/%7Ehseigel/bug_8009595/>
>>>>
>>>> Bug link at http://bugs.sun.com/view_bug.do?bug_id=8009595
>>>>
>>>> The change was tested by hand to ensure that the deprecate message 
>>>> appears when the option is specified and to verify that the option 
>>>> had no affect.  Additional testing was done with the JCK Lang and 
>>>> VM, JTREG runtime, ute vm.quick.testlist, and JPRT tests.
>>>>
>>>> Thank you!
>>>> Harold
>>>
>>
>