RFR: 8271515: Integration of JEP 417: Vector API (Third Incubator) [v8]

[Paul Sandoz]

> This PR improves the performance of vector operations that accept masks on architectures that support masking in hardware, specifically Intel AVX512 and ARM SVE.
> 
> On architectures that do not support masking in hardware the same technique as before is applied to most operations, specifically composition using blend.
> 
> Masked loads/stores are a special form of masked operation that require additional care to ensure out-of-bounds access throw exceptions. The range checking has not been fully optimized and will require further work.
> 
> No API enhancements were required and only a few additional tests were needed.

Paul Sandoz has updated the pull request incrementally with two additional commits since the last revision:

 - Merge pull request #2 from nsjian/vector-conversion-fix
   
   AArch64: Incorrect SVE double to int and float to long vector conversion
 - Incorrect double to int and float to long vector conversion
   
   Like JDK-8276151, SVE vector double to int and float to long
   conversions have similar issue. According to Java language
   specification [1], we should convert double/float to
   integer/long directly, instead of converting to long/int and then
   narrowing/extending to target types. Test cases will be updated in
   JDK-8276151.
   
   [1] https://docs.oracle.com/javase/specs/jls/se17/html/jls-5.html#jls-5.1.3

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/5873/files
  - new: https://git.openjdk.java.net/jdk/pull/5873/files/c9a77225..571e6f39

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=5873&range=07
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=5873&range=06-07

  Stats: 40 lines in 2 files changed: 22 ins; 4 del; 14 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5873.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5873/head:pull/5873

PR: https://git.openjdk.java.net/jdk/pull/5873