RFR: 8353741: Eliminate table lookup in UUID.toString [v8]

[Roger Riggs]

On Wed, 21 May 2025 00:57:30 GMT, Shaojin Wen <swen at openjdk.org> wrote:

>> Improve the performance of UUID::toString by using Long.expand and SWAR (SIMD within a register) instead of table lookup. Eliminating the table lookup can also avoid the performance degradation problem when the cache misses.
>
> Shaojin Wen has updated the pull request incrementally with one additional commit since the last revision:
> 
>   fix comments, from @j3graham

Looks good. Thanks for the detailed comments and vectorized hex to string conversion.

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Marked as reviewed by rriggs (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/22928#pullrequestreview-2858893329