Hi Claes,

Your proposed changes to ParseUtil look reasonable
to me, though I had to carefully compare the characters
in the range (c >= '&' && c <= ':') with the
L_ENCODED / H_ENCODED masks to convince myself
that there was no behavior change to

I wonder whether this would deserve some additional
comment - though I'm not sure how it could be formulated.

Given the sensitivity of the impacted code maybe it would
be prudent to wait for a second review before pushing.

best regards,

-- daniel

On 14/02/2018 15:30, Claes Redestad wrote:

as a means to improve startup in some applications, please review this set of small improvements to improve both interpreted and compiled performance of creating and handling certain jar URLs. Some of the changes in sun.net.www.ParseUtil::encodePath have a small, positive effect when dealing with other types of path resources.

Bug: https://bugs.openjdk.java.net/browse/JDK-8197849

Webrev: http://cr.openjdk.java.net/~redestad/8197849/jdk.00/

This shaves off a percent or so of the total bytecode execution in a few of our startup tests:

- ParseUtil::encodePath cost is reduced ~20% during startup, averaging ~10-15% faster for typical inputs after JIT. Weird examples like paths only consisting of slashes and dots can be seen to take a small hit due to not getting special treatment.

- ParseUtil::canonizeString cost on startup reduced by 50% (~15% improvement after JIT) for typical inputs by adding a test to return directly if there's no need to "canonize" the string (which is typically always the case for well-formed jar files). I added a sanity test to ensure I didn't accidentally change semantics of cases that would lead to canonicalization.

- Removed a couple of unnecessary allocation in sun.net.www.protocol.jar.Handler. Maybe there are some good reasons not to make ParseUtil a final utility class with only static methods and a private constructor, though...



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