RFR: 8245677: Optimize lookups in empty HashMap

[Claes Redestad]

Hi Roger,

thank you for reviewing.

I felt adding the micro wouldn't add much, since HashMap is such a
common occurrence in various benchmarks already.

/Claes

On 2020-05-26 16:32, Roger Riggs wrote:
> +1,
> 
> Looks fine.
> 
> Should the benchmark be included?
> 
> Thanks, Roger
> 
> 
> On 5/25/20 8:12 AM, Jim Laskey wrote:
>> +1
>>
>> (Copyright date)
>>
>>> On May 25, 2020, at 7:02 AM, Claes Redestad 
>>> <claes.redestad at oracle.com> wrote:
>>>
>>> Hi,
>>>
>>> sponsoring this patch from Christoph Dreis.
>>>
>>> By pushing down the hash calculation we can optimize lookups
>>> in empty HashMaps (also helps LinkedHashMap).
>>>
>>> Bug:    https://bugs.openjdk.java.net/browse/JDK-8245677
>>> Webrev: http://cr.openjdk.java.net/~redestad/8245677/open.00/
>>>
>>> Testing: tier1+2
>>>
>>> Original report: 
>>> https://mail.openjdk.java.net/pipermail/core-libs-dev/2020-May/066530.html 
>>>
>>>
>>> /Claes
>