RFR: 8368349: Add library notes discussing abs and IEEE 754 operations

[Joe Darcy]

On Tue, 23 Sep 2025 13:06:05 GMT, Raffaello Giulietti <rgiulietti at openjdk.org> wrote:

> @jddarcy Why can't we simply require a zero sign bit, like IEEE 754 does? After all, IIUC this is exactly what the implementation does.

As an intrinsic candidate, the method could be replaced with a hardware instruction and earlier editions of IEEE 754 didn't require the NaN behavior so hardware might not implement that policy. I could check on what contemporary chips are specified to do.

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PR Comment: https://git.openjdk.org/jdk/pull/27443#issuecomment-3324747241