RFR: 8279651: [vectorapi] Implement the missing intrinsics for casting from integrals on x64 [v4]

[Quan Anh Mai]

> Hi,
> 
> This patch implements the remaining casts from integral types on x64.
> 
> Thank you very much.

Quan Anh Mai has updated the pull request incrementally with one additional commit since the last revision:

  typo

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/7002/files
  - new: https://git.openjdk.java.net/jdk/pull/7002/files/8401d390..a344ff09

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7002&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7002&range=02-03

  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7002.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7002/head:pull/7002

PR: https://git.openjdk.java.net/jdk/pull/7002