RFR: 8227505: SuperWordLoopUnrollAnalysis may lead to over loop unrolling

Jie Fu fujie at loongson.cn
Wed Aug 21 07:51:04 UTC 2019

On 2019/8/20 下午4:44, Jie Fu wrote:
>> Also the loop did not get unrolled after vectorization.
> Yes. I can reproduce it on my computer.
> I'm surprised that the unrolled version seems a bit slow (on my 
> computer) again.

Not true.
The difference of performance came from different jdk-images used in my 

After vectorization, the unrolled main-loop is a performance bug caused 
by my previous patch.
Thanks Vivek for correcting me.
Will update the webrev to fix this bug later.

Thanks a lot.
Best regards,

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