[jdk21u-dev] Integrated: 8318158: RISC-V: implement roundD/roundF intrinsics

[Olga Mikhaltsova]

On Fri, 12 Jan 2024 11:58:59 GMT, Olga Mikhaltsova <omikhaltcova at openjdk.org> wrote:

> I would like to backport [JDK-8318158](https://bugs.openjdk.org/browse/JDK-8318158) to jdk21u in order to optimize performance in double/float rounding operations by means of intrinsics.
> The patch applied cleanly.
> Tested: tier1 tests passed.
> 
> The benchmark shows the following performance improvement on the T-Head RVB-ICE board:
> **Before**
> 
> Benchmark                              (TESTSIZE)   Mode  Cnt   Score   Error   Units
> FpRoundingBenchmark.test_round_double        2048  thrpt   15  58.679 ± 0.965  ops/ms
> FpRoundingBenchmark.test_round_float         2048  thrpt   15  49.252 ± 0.887  ops/ms
> 
> **After**
> 
> Benchmark                              (TESTSIZE)   Mode  Cnt    Score   Error   Units
> FpRoundingBenchmark.test_round_double        2048  thrpt   15  117.264 ± 1.254  ops/ms
> FpRoundingBenchmark.test_round_float         2048  thrpt   15  119.752 ± 1.751  ops/ms

This pull request has now been integrated.

Changeset: ada400cf
Author:    Olga Mikhaltsova <omikhaltcova at openjdk.org>
URL:       https://git.openjdk.org/jdk21u-dev/commit/ada400cffe35140d62452e3899e5a04a40b737c8
Stats:     82 lines in 3 files changed: 82 ins; 0 del; 0 mod

8318158: RISC-V: implement roundD/roundF intrinsics

Backport-of: 19147f326c6b0e78fe72f9a7e7100047f16a0921

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

PR: https://git.openjdk.org/jdk21u-dev/pull/161