RFR: 8302191: Performance degradation for float/double modulo on Linux [v3]

[Jan Kratochvil]

> I have OCA already processed/approved. I am not Author but my Author request is being processed these days (sent to Rob McKenna).
> I did regression test x86_64 OpenJDK-8. I will leave other regression testing on GHA.
> The patch (and former GCC performance regression) affects only x86_64+i686.

Jan Kratochvil has updated the pull request incrementally with one additional commit since the last revision:

  Update according to the upstream review by David Holmes.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/12508/files
  - new: https://git.openjdk.org/jdk/pull/12508/files/d00f1a5a..44ba5348

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12508&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12508&range=01-02

  Stats: 66 lines in 3 files changed: 30 ins; 30 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/12508.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12508/head:pull/12508

PR: https://git.openjdk.org/jdk/pull/12508