[vectorIntrinsics] RFR: Merge panama-vector:master [v2]

[Ningsheng Jian]

> Some aarch64 conflicts resolved. Verified on AArch64 and x86.

Ningsheng Jian has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 738 commits:

 - Merge 'panama-vector/master' into vectorIntrinsics
 - Merge panama-vector:master
   
   Reviewed-by: eliu
 - Merge panama-vector:master
   
   Reviewed-by: jbhateja, psandoz
 - 8263532: C2: Improve vector box elimination for Phi nodes
   
   Reviewed-by: psandoz
 - Merge panama-vector:master
   
   Co-authored-by: Ningsheng Jian <njian at openjdk.org>
 - Optimize mem barriers for ByteBuffer cases
   
   Reviewed-by: psandoz, vlivanov
 - 8271009: AArch64: Wrap duplicated SVE instructions into a single method
   
   Reviewed-by: njian, xgong
 - 8271005: AArch64: Add SVE codegen for VectorMask reduction nodes
   
   Reviewed-by: njian, eliu
 - Merge panama-vector:master
   
   Reviewed-by: xgong, sviswanathan
 - 8269264: Some more cleanups for Vector API SVE support
   
   Reviewed-by: xgong
 - ... and 728 more: https://git.openjdk.java.net/panama-vector/compare/9d3379b9...2c8916b8

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

Changes: https://git.openjdk.java.net/panama-vector/pull/129/files
 Webrev: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=129&range=01
  Stats: 67647 lines in 112 files changed: 67563 ins; 18 del; 66 mod
  Patch: https://git.openjdk.java.net/panama-vector/pull/129.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-vector pull/129/head:pull/129

PR: https://git.openjdk.java.net/panama-vector/pull/129