RFR: 8302191: Performance degradation for float/double modulo on Linux [v5]

[Andrey Turbanov]

On Wed, 1 Mar 2023 12:03:54 GMT, Jan Kratochvil <duke at openjdk.org> wrote:

>> 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:
> 
>   Fix copyright author.

test/micro/org/openjdk/bench/vm/floatingpoint/DremFrem.java line 177:

> 175:             double quiet_nan2     = Double.longBitsToDouble(0x7ffc000000000002l);
> 176:             double signaling_nan1 = Double.longBitsToDouble(0x7ffa000000000001l);
> 177:             double signaling_nan2 = Double.longBitsToDouble(0x7ffa000000000002l);

Suggestion:

            double quiet_nan1     = Double.longBitsToDouble(0x7ffc000000000001L);
            double quiet_nan2     = Double.longBitsToDouble(0x7ffc000000000002L);
            double signaling_nan1 = Double.longBitsToDouble(0x7ffa000000000001L);
            double signaling_nan2 = Double.longBitsToDouble(0x7ffa000000000002L);

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