RFR: 8300926: Several startup regressions ~6-70% in 21-b6 all platforms [v4]

[Robbin Ehn]

On Thu, 23 Feb 2023 01:09:49 GMT, Daniel D. Daugherty <dcubed at openjdk.org> wrote:

>> src/hotspot/share/classfile/vmClasses.cpp line 252:
>> 
>>> 250:   Dictionary* dictionary = loader_data->dictionary();
>>> 251:   dictionary->add_klass(THREAD, klass->name(), klass);
>>> 252:   SystemDictionary::add_to_hierarchy(klass, THREAD);
>> 
>> One more small changes please.  Can you make JavaThread* current the first parameter so this doesn't look like we're failing to throw an exception from these calls?
>
> This call to `SystemDictionary::add_to_hierarchy()` was not previously
> done while grabbing the `Compile_lock` and now we'll do that.
> 
> This specific call is made while this assert() is true:
> ```assert(!Universe::is_fully_initialized(), "We can make short cuts only during VM initialization");```
> 
> so very early in the life of the VM.

Grabbing the lock should not be problematic.

-------------

PR: https://git.openjdk.org/jdk/pull/12585