RFR: 8291555: Implement alternative fast-locking scheme [v28]

[Roman Kennke]

On Thu, 16 Mar 2023 20:50:12 GMT, Daniel D. Daugherty <dcubed at openjdk.org> wrote:

>> Roman Kennke has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Several changes (mostly cosmetic) in response to reviews
>
> src/hotspot/cpu/x86/x86_32.ad line 617:
> 
>> 615:   int bangsize = C->output()->bang_size_in_bytes();
>> 616: 
>> 617:   __ verified_entry(framesize, C->output()->need_stack_bang(bangsize)?bangsize:0, C->in_24_bit_fp_mode(), C->stub_function() != NULL);
> 
> Why did this change from `nullptr` -> `NULL`?

I reverted that part back to upstream state (at least what is in JDK-21+13).

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PR: https://git.openjdk.org/jdk/pull/10907