On Fri, 4 Aug 2023 19:45:56 GMT, Leonid Mesnik <lmes...@openjdk.org> wrote:
>> The fix adds posting VmObjectAlloc events by
>> Unsafe.allocateInstance(Class<?> cls). The previous attempt to post event
>> directly from 'LibraryCallKit::inline_unsafe_allocate()' cause performance
>> regression even if jvmti event is not enabled. Some optimizations have been
>> disabled just because possible usage and escaping of newly allocated object.
>> So event posting is doing by returning to interpreter if events are enabled.
>>
>> I verified that that performance (run locally only) of
>> org.renaissance.jdk.streams.JmhScrabble.runOperation
>> doesn't change if events are not enabled.
>>
>> There might be other intrinsics like
>> 'LibraryCallKit::inline_unsafe_newArray()' where VM allocate memory. I'm
>> going to file separate issue to find and fix them.
>>
>> Many thanks to Tobias H. for proposed solution.
>>
>> Testing with all tiers.
>
> Leonid Mesnik has updated the pull request incrementally with one additional
> commit since the last revision:
>
> The too many deopts check should be first.
Looks good to me.
src/hotspot/share/opto/library_call.cpp line 2845:
> 2843: }
> 2844: if (stopped())
> 2845: return true;
Suggestion:
if (stopped()) {
return true;
}
-------------
Marked as reviewed by thartmann (Reviewer).
PR Review: https://git.openjdk.org/jdk/pull/15110#pullrequestreview-1568773710
PR Review Comment: https://git.openjdk.org/jdk/pull/15110#discussion_r1287968367
