RFR: 8321021: RISC-V: C2 VectorUCastB2X [v4]

[Hamlin Li]

> Hi,
> Can you help to review the patch to add support for some vector intrinsics?
> Also complement various tests on riscv.
> Thanks.
> 
> ## Test
> test/hotspot/jtreg/compiler/vectorapi/
> test/hotspot/jtreg/compiler/vectorization/

Hamlin Li has updated the pull request incrementally with two additional commits since the last revision:

 - remove ucast from i/s/b to float
 - revert some chnage; remove effect(TEMP_DEF dst) for non-extending intrinsics

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/18040/files
  - new: https://git.openjdk.org/jdk/pull/18040/files/646955f0..cc43650b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18040&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18040&range=02-03

  Stats: 93 lines in 1 file changed: 23 ins; 50 del; 20 mod
  Patch: https://git.openjdk.org/jdk/pull/18040.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18040/head:pull/18040

PR: https://git.openjdk.org/jdk/pull/18040