[vector api] RFR: Implement Vector API andAll/orAll/xorAll for AArch64 NEON

[Joshua Zhu (Arm Technology China)]

Hi John,

> Here's a recent javadoc from Kishor Kharbas:
> 
> http://cr.openjdk.java.net/~kkharbas/vector-api/javadoc/VectorApi-
> JavaDoc.05/jdk.incubator.vector/jdk/incubator/vector/package-
> summary.html
> 
> http://cr.openjdk.java.net/~kkharbas/vector-api/javadoc/
> 
> It's good reading!  After we all work it over it will be even better, of course.
> There will also be a formal CSR review in the not-too-distant future, since
> that is part of the JEP process.

In the Javadoc, it mentioned the species instance for a specific combination of element type and shape can be obtained.
The default scalar implementation will be used if some specific species(like FloatVector.SPECIES_512) is not supported in a platform.
I think it is more reasonable to only make SPECIES_PREFERRED public, why are these specific species exposed to API users?

For tail loop handling, the scalar computation is required to process the tail of elements, the length of which is smaller than the species length.
Therefore I think the loop control [1] is in future road map, will not be part of this CSR review.

[1] https://bugs.openjdk.java.net/browse/JDK-8221358

Best Regards,
Joshua