[vectorIntrinsics+mask] RFR: 8273949: Intrinsic creation for VectorMask.toLong operation. [v4]

[Jatin Bhateja]

> Summary of changes:
> - Intrinsification of VectorMask.toLong() API.
> - Supports inline expansion for both AVX512 and non-AVX512 targets.
> - Used toLong() API to optimize existing Java API implementation of VectorMask.laneIsSet() operation.
> 
> Following performance number are generated using JMH benchmark modification included with the patch.
> 
> System:  Intel(R) Xeon(R) Platinum 8280 CPU @ 2.70GHz (Cascade Lake Server 28C 2S)
> 
> Benchmark | VECSIZE | Baseline Score (ops/ms) | With Opt (ops/ms) | Gain Ratio
> -- | -- | -- | -- | --
> MaskQueryOperationsBenchmark.testToLongByte | 128 | 90451.424 | 346941.379 | 3.835665196
> MaskQueryOperationsBenchmark.testToLongByte | 256 | 63127.764 | 338331.425 | 5.359471072
> MaskQueryOperationsBenchmark.testToLongByte | 512 | 40543.264 | 313836.333 | 7.740776199
> MaskQueryOperationsBenchmark.testToLongLong | 128 | 171989.714 | 152872.758 | 0.88884826
> MaskQueryOperationsBenchmark.testToLongLong | 256 | 164702.273 | 324794.578 | 1.972010295
> MaskQueryOperationsBenchmark.testToLongLong | 512 | 122667.916 | 318060.096 | 2.59285481
> MaskQueryOperationsBenchmark.testToLongShort | 128 | 122656.408 | 346691.082 | 2.826522378
> MaskQueryOperationsBenchmark.testToLongShort | 256 | 96838.555 | 360909.28 | 3.726917239
> MaskQueryOperationsBenchmark.testToLongShort | 512 | 63119.009 | 313075.159 | 4.960077225
> MaskQueryOperationsBenchmark.testToLonglong | 128 | 180855.623 | 324620.433 | 1.794914792
> MaskQueryOperationsBenchmark.testToLonglong | 256 | 122705.631 | 324315.916 | 2.643040204
> MaskQueryOperationsBenchmark.testToLonglong | 512 | 90396.687 | 324318.095 | 3.58772103

Jatin Bhateja has updated the pull request incrementally with one additional commit since the last revision:

  8273949: Review comments resolution.

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

Changes:
  - all: https://git.openjdk.java.net/panama-vector/pull/126/files
  - new: https://git.openjdk.java.net/panama-vector/pull/126/files/6b38d057..f1816ce8

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=126&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=126&range=02-03

  Stats: 5 lines in 2 files changed: 0 ins; 0 del; 5 mod
  Patch: https://git.openjdk.java.net/panama-vector/pull/126.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-vector pull/126/head:pull/126

PR: https://git.openjdk.java.net/panama-vector/pull/126