RFR: 8264104: Eliminate unnecessary vector mask conversion during VectorUnbox for floating point VectorMask [v2]

[Xiaohong Gong]

On Thu, 8 Apr 2021 15:00:10 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

>> Xiaohong Gong has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains one new commit since the last revision:
>> 
>>   8264104: Eliminate unnecessary vector mask conversion during VectorUnbox for floating point VectorMask
>
> Okay.

Hi @iwanowww , I'v updated the codes to use `VectorMaskCast` for vector mask casting with the same element size and vector length. Would you mind having a look again? Thanks!

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

PR: https://git.openjdk.java.net/jdk/pull/3238