Hi Claes and Andriy! It looks good overall.
I wonder if it'll be even faster if the fast path were implemented in StringLatin1 (for compact strings only) and was called via SharedSecrets/JavaLangAccess?
Then, you could operate directly on bytes and avoid dealing with longs. With kind regards, Ivan On 2/28/20 6:22 AM, Claes Redestad wrote:
Hi all, please review this patch to optimize UUID#fromString. Jon Chambers originally proposed a patch that used a strict parser to get a similar speed-up, but I failed to adapt it in a way that could fall back to the less strict behavior while maintaining a reasonable speed-up in the fast-path case. Sorry, Jon! The patch proposed here was recently contributed by Andriy Plokhotnyuk (OCA signed), and manages to get more than a 3x speed-up on the new fromString microbenchmark, while falling back gently to the current, less strict implementation if ever needed. I've done some light edits, and added a simple microbenchmark. Bug: https://bugs.openjdk.java.net/browse/JDK-8196334 Webrev: http://cr.openjdk.java.net/~redestad/8196334/open.00/ Testing: tier1-3 Thanks! /Claes
-- With kind regards, Ivan Gerasimov
