On Wed, 7 Jul 2021 20:29:37 GMT, Brian Burkhalter <b...@openjdk.org> wrote:

> 
> 
> With this change there is no measurable effect on performance on macOS, but 
> on Linux there is approximately a 10% throughput improvement.

The improvement is with the default options, without turning intrinsics off?

I'm somewhat indifferent toward the change. On platforms with intrinsics, the 
intrinsic hardware instruction should run quickly regardless of how the Java 
code is implemented. On older versions of the platform the bitwise conversion 
(longBitsToDouble and friends) was slow, so the floating-point operations would 
be faster. However, the bitwise conversion should now be fast everywhere.

As a minor behavioral difference, the behavior on some NaN values would change 
in terms of which NaN was returned as a result, but any NaN is allowed by the 
spec.

If the new code is faster with intrinsics enabled on a common platform, I'd be 
happy to review a slightly refactored version of the PR.

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

PR: https://git.openjdk.java.net/jdk/pull/4711

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