[vectorIntrinsics+mask] RFR: 8265109: SVE predicate register allocation support for vectorIntrinsics [v2]

[Ningsheng Jian]

> This is the SVE predicate register allocation part for Vector API masking support. Since we don't have sufficent usages to test it in
> jdk/jdk, and based on @sviswa7 's proposal [1], we would like to put it to vectorIntrinsics+mask first and get tested here with further predicate-based vector masking support, though so far no issue found with Xiaohong's initial Vector API masking support.
> 
> [1] https://mail.openjdk.java.net/pipermail/panama-dev/2021-April/012920.html

Ningsheng Jian has updated the pull request incrementally with one additional commit since the last revision:

  Address review comment from Jatin.

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

Changes:
  - all: https://git.openjdk.java.net/panama-vector/pull/65/files
  - new: https://git.openjdk.java.net/panama-vector/pull/65/files/41b9349a..27e3eebb

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=65&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=65&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/panama-vector/pull/65.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-vector pull/65/head:pull/65

PR: https://git.openjdk.java.net/panama-vector/pull/65