RFR: 8349764: RISC-V: C1: Improve Class.isInstance intrinsic [v2]

[Gui Cao]

> Follow this patch https://github.com/openjdk/jdk/pull/22491, RISC-V implementation for Class.isInstance intrinsic.
> 
> 
> ### JMH numbers (tested on milkv megrez with hotspot client build):
> 
> #### before this patch:
> 
> Benchmark                             Mode  Cnt    Score   Error  Units
> SecondarySupersLookup.testNegative00  avgt   15   48.589 ± 0.981  ns/op
> SecondarySupersLookup.testNegative01  avgt   15   48.577 ± 0.297  ns/op
> SecondarySupersLookup.testNegative02  avgt   15   48.760 ± 0.740  ns/op
> SecondarySupersLookup.testNegative03  avgt   15   48.442 ± 0.029  ns/op
> SecondarySupersLookup.testNegative04  avgt   15   48.453 ± 0.095  ns/op
> SecondarySupersLookup.testNegative05  avgt   15   48.435 ± 0.025  ns/op
> SecondarySupersLookup.testNegative06  avgt   15   48.540 ± 0.476  ns/op
> SecondarySupersLookup.testNegative07  avgt   15   48.452 ± 0.032  ns/op
> SecondarySupersLookup.testNegative08  avgt   15   48.466 ± 0.034  ns/op
> SecondarySupersLookup.testNegative09  avgt   15   48.478 ± 0.132  ns/op
> SecondarySupersLookup.testNegative10  avgt   15   48.435 ± 0.032  ns/op
> SecondarySupersLookup.testNegative16  avgt   15   48.440 ± 0.027  ns/op
> SecondarySupersLookup.testNegative20  avgt   15   47.977 ± 0.989  ns/op
> SecondarySupersLookup.testNegative30  avgt   15   48.655 ± 0.487  ns/op
> SecondarySupersLookup.testNegative32  avgt   15   48.566 ± 0.251  ns/op
> SecondarySupersLookup.testNegative40  avgt   15   48.513 ± 0.196  ns/op
> SecondarySupersLookup.testNegative50  avgt   15   48.454 ± 0.075  ns/op
> SecondarySupersLookup.testNegative55  avgt   15   71.670 ± 1.632  ns/op
> SecondarySupersLookup.testNegative56  avgt   15   70.923 ± 1.679  ns/op
> SecondarySupersLookup.testNegative57  avgt   15   70.140 ± 0.048  ns/op
> SecondarySupersLookup.testNegative58  avgt   15   70.473 ± 0.726  ns/op
> SecondarySupersLookup.testNegative59  avgt   15   70.127 ± 0.022  ns/op
> SecondarySupersLookup.testNegative60  avgt   15   82.525 ± 1.178  ns/op
> SecondarySupersLookup.testNegative61  avgt   15   81.647 ± 0.758  ns/op
> SecondarySupersLookup.testNegative62  avgt   15   82.347 ± 1.943  ns/op
> SecondarySupersLookup.testNegative63  avgt   15  129.188 ± 1.550  ns/op
> SecondarySupersLookup.testNegative64  avgt   15  130.274 ± 1.668  ns/op
> SecondarySupersLookup.testPositive01  avgt   15   63.390 ± 0.222  ns/op
> SecondarySupersLookup.testPositive02  avgt   15   63.435 ± 0.027  ns/op
> SecondarySupersLookup.testPositive03  avgt   15   63.469 ± 0.080  ns/op
> SecondarySupersLookup.testPositive04  avgt   15   63.896 ...

Gui Cao has updated the pull request incrementally with one additional commit since the last revision:

  Update for Hamlin's comment

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/23551/files
  - new: https://git.openjdk.org/jdk/pull/23551/files/c2a6cffe..2ec9dac1

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23551&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23551&range=00-01

  Stats: 8 lines in 1 file changed: 1 ins; 1 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/23551.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23551/head:pull/23551

PR: https://git.openjdk.org/jdk/pull/23551